-/* $Cambridge: exim/src/src/smtp_in.c,v 1.25 2005/09/12 10:08:54 ph10 Exp $ */
-
/*************************************************
* Exim - an Internet mail transport agent *
*************************************************/
-/* Copyright (c) University of Cambridge 1995 - 2005 */
+/* Copyright (c) University of Cambridge 1995 - 2018 */
/* See the file NOTICE for conditions of use and distribution. */
/* Functions for handling an incoming SMTP call. */
#include "exim.h"
+#include <assert.h>
/* Initialize for TCP wrappers if so configured. It appears that the macro
int allow_severity = LOG_INFO;
int deny_severity = LOG_NOTICE;
+uschar *tcp_wrappers_name;
#endif
/* Size of buffer for reading SMTP commands. We used to use 512, as defined
by RFC 821. However, RFC 1869 specifies that this must be increased for SMTP
commands that accept arguments, and this in particular applies to AUTH, where
-the data can be quite long. */
+the data can be quite long. More recently this value was 2048 in Exim;
+however, RFC 4954 (circa 2007) recommends 12288 bytes to handle AUTH. Clients
+such as Thunderbird will send an AUTH with an initial-response for GSSAPI.
+The maximum size of a Kerberos ticket under Windows 2003 is 12000 bytes, and
+we need room to handle large base64-encoded AUTHs for GSSAPI.
+*/
-#define cmd_buffer_size 2048
+#define SMTP_CMD_BUFFER_SIZE 16384
/* Size of buffer for reading SMTP incoming packets */
-#define in_buffer_size 8192
+#define IN_BUFFER_SIZE 8192
/* Structure for SMTP command list */
typedef struct {
- char *name;
+ const char *name;
int len;
short int cmd;
short int has_arg;
VRFY_CMD, EXPN_CMD, NOOP_CMD, /* RFC as requiring synchronization */
ETRN_CMD, /* This by analogy with TURN from the RFC */
STARTTLS_CMD, /* Required by the STARTTLS RFC */
+ TLS_AUTH_CMD, /* auto-command at start of SSL */
/* This is a dummy to identify the non-sync commands when pipelining */
NON_SYNC_CMD_NON_PIPELINING,
+ /* RFC3030 section 2: "After all MAIL and RCPT responses are collected and
+ processed the message is sent using a series of BDAT commands"
+ implies that BDAT should be synchronized. However, we see Google, at least,
+ sending MAIL,RCPT,BDAT-LAST in a single packet, clearly not waiting for
+ processing of the RCPT response(s). We shall do the same, and not require
+ synch for BDAT. Worse, as the chunk may (very likely will) follow the
+ command-header in the same packet we cannot do the usual "is there any
+ follow-on data after the command line" even for non-pipeline mode.
+ So we'll need an explicit check after reading the expected chunk amount
+ when non-pipe, before sending the ACK. */
+
+ BDAT_CMD,
+
/* I have been unable to find a statement about the use of pipelining
with AUTH, so to be on the safe side it is here, though I kind of feel
it should be up there with the synchronized commands. */
QUIT_CMD, HELP_CMD,
+#ifdef SUPPORT_PROXY
+ PROXY_FAIL_IGNORE_CMD,
+#endif
+
/* These are specials that don't correspond to actual commands */
EOF_CMD, OTHER_CMD, BADARG_CMD, BADCHAR_CMD, BADSYN_CMD,
TOO_MANY_NONMAIL_CMD };
+/* This is a convenience macro for adding the identity of an SMTP command
+to the circular buffer that holds a list of the last n received. */
+
+#define HAD(n) \
+ smtp_connection_had[smtp_ch_index++] = n; \
+ if (smtp_ch_index >= SMTP_HBUFF_SIZE) smtp_ch_index = 0
+
/*************************************************
* Local static variables *
*************************************************/
+static struct {
+ BOOL auth_advertised :1;
+#ifndef DISABLE_TLS
+ BOOL tls_advertised :1;
+#endif
+ BOOL dsn_advertised :1;
+ BOOL esmtp :1;
+ BOOL helo_required :1;
+ BOOL helo_verify :1;
+ BOOL helo_seen :1;
+ BOOL helo_accept_junk :1;
+#ifdef SUPPORT_PIPE_CONNECT
+ BOOL pipe_connect_acceptable :1;
+#endif
+ BOOL rcpt_smtp_response_same :1;
+ BOOL rcpt_in_progress :1;
+ BOOL smtp_exit_function_called :1;
+#ifdef SUPPORT_I18N
+ BOOL smtputf8_advertised :1;
+#endif
+} fl = {
+ .helo_required = FALSE,
+ .helo_verify = FALSE,
+ .smtp_exit_function_called = FALSE,
+};
+
static auth_instance *authenticated_by;
-static BOOL auth_advertised;
-#ifdef SUPPORT_TLS
-static BOOL tls_advertised;
-#endif
-static BOOL esmtp;
-static BOOL helo_required = FALSE;
-static BOOL helo_verify = FALSE;
-static BOOL helo_seen;
-static BOOL helo_accept_junk;
-static BOOL count_nonmail;
-static BOOL pipelining_advertised;
+static int count_nonmail;
static int nonmail_command_count;
static int synprot_error_count;
static int unknown_command_count;
static int sync_cmd_limit;
static int smtp_write_error = 0;
-static uschar *cmd_buffer;
+static uschar *rcpt_smtp_response;
+static uschar *smtp_data_buffer;
+static uschar *smtp_cmd_data;
/* We need to know the position of RSET, HELO, EHLO, AUTH, and STARTTLS. Their
final fields of all except AUTH are forced TRUE at the start of a new message
forced TRUE, to allow for the re-authentication that can happen at that point.
QUIT is also "falsely" labelled as a mail command so that it doesn't up the
-count of non-mail commands and possibly provoke an error. */
+count of non-mail commands and possibly provoke an error.
+
+tls_auth is a pseudo-command, never expected in input. It is activated
+on TLS startup and looks for a tls authenticator. */
static smtp_cmd_list cmd_list[] = {
+ /* name len cmd has_arg is_mail_cmd */
+
{ "rset", sizeof("rset")-1, RSET_CMD, FALSE, FALSE }, /* First */
{ "helo", sizeof("helo")-1, HELO_CMD, TRUE, FALSE },
{ "ehlo", sizeof("ehlo")-1, EHLO_CMD, TRUE, FALSE },
{ "auth", sizeof("auth")-1, AUTH_CMD, TRUE, TRUE },
- #ifdef SUPPORT_TLS
+#ifndef DISABLE_TLS
{ "starttls", sizeof("starttls")-1, STARTTLS_CMD, FALSE, FALSE },
- #endif
+ { "tls_auth", 0, TLS_AUTH_CMD, FALSE, FALSE },
+#endif
/* If you change anything above here, also fix the definitions below. */
{ "mail from:", sizeof("mail from:")-1, MAIL_CMD, TRUE, TRUE },
{ "rcpt to:", sizeof("rcpt to:")-1, RCPT_CMD, TRUE, TRUE },
{ "data", sizeof("data")-1, DATA_CMD, FALSE, TRUE },
+ { "bdat", sizeof("bdat")-1, BDAT_CMD, TRUE, TRUE },
{ "quit", sizeof("quit")-1, QUIT_CMD, FALSE, TRUE },
{ "noop", sizeof("noop")-1, NOOP_CMD, TRUE, FALSE },
{ "etrn", sizeof("etrn")-1, ETRN_CMD, TRUE, FALSE },
#define CMD_LIST_EHLO 2
#define CMD_LIST_AUTH 3
#define CMD_LIST_STARTTLS 4
+#define CMD_LIST_TLS_AUTH 5
-static uschar *protocols[] = {
+/* This list of names is used for performing the smtp_no_mail logging action.
+It must be kept in step with the SCH_xxx enumerations. */
+
+static uschar *smtp_names[] =
+ {
+ US"NONE", US"AUTH", US"DATA", US"BDAT", US"EHLO", US"ETRN", US"EXPN",
+ US"HELO", US"HELP", US"MAIL", US"NOOP", US"QUIT", US"RCPT", US"RSET",
+ US"STARTTLS", US"VRFY" };
+
+static uschar *protocols_local[] = {
US"local-smtp", /* HELO */
US"local-smtps", /* The rare case EHLO->STARTTLS->HELO */
US"local-esmtp", /* EHLO */
US"local-esmtpa", /* EHLO->AUTH */
US"local-esmtpsa" /* EHLO->STARTTLS->EHLO->AUTH */
};
+static uschar *protocols[] = {
+ US"smtp", /* HELO */
+ US"smtps", /* The rare case EHLO->STARTTLS->HELO */
+ US"esmtp", /* EHLO */
+ US"esmtps", /* EHLO->STARTTLS->EHLO */
+ US"esmtpa", /* EHLO->AUTH */
+ US"esmtpsa" /* EHLO->STARTTLS->EHLO->AUTH */
+ };
#define pnormal 0
#define pextend 2
#define pcrpted 1 /* added to pextend or pnormal */
#define pauthed 2 /* added to pextend */
-#define pnlocal 6 /* offset to remove "local" */
+
+/* Sanity check and validate optional args to MAIL FROM: envelope */
+enum {
+ ENV_MAIL_OPT_NULL,
+ ENV_MAIL_OPT_SIZE, ENV_MAIL_OPT_BODY, ENV_MAIL_OPT_AUTH,
+#ifndef DISABLE_PRDR
+ ENV_MAIL_OPT_PRDR,
+#endif
+ ENV_MAIL_OPT_RET, ENV_MAIL_OPT_ENVID,
+#ifdef SUPPORT_I18N
+ ENV_MAIL_OPT_UTF8,
+#endif
+ };
+typedef struct {
+ uschar * name; /* option requested during MAIL cmd */
+ int value; /* enum type */
+ BOOL need_value; /* TRUE requires value (name=value pair format)
+ FALSE is a singleton */
+ } env_mail_type_t;
+static env_mail_type_t env_mail_type_list[] = {
+ { US"SIZE", ENV_MAIL_OPT_SIZE, TRUE },
+ { US"BODY", ENV_MAIL_OPT_BODY, TRUE },
+ { US"AUTH", ENV_MAIL_OPT_AUTH, TRUE },
+#ifndef DISABLE_PRDR
+ { US"PRDR", ENV_MAIL_OPT_PRDR, FALSE },
+#endif
+ { US"RET", ENV_MAIL_OPT_RET, TRUE },
+ { US"ENVID", ENV_MAIL_OPT_ENVID, TRUE },
+#ifdef SUPPORT_I18N
+ { US"SMTPUTF8",ENV_MAIL_OPT_UTF8, FALSE }, /* rfc6531 */
+#endif
+ /* keep this the last entry */
+ { US"NULL", ENV_MAIL_OPT_NULL, FALSE },
+ };
/* When reading SMTP from a remote host, we have to use our own versions of the
C input-reading functions, in order to be able to flush the SMTP output only
static int smtp_had_error;
+/* forward declarations */
+static int smtp_read_command(BOOL check_sync, unsigned buffer_lim);
+static int synprot_error(int type, int code, uschar *data, uschar *errmess);
+static void smtp_quit_handler(uschar **, uschar **);
+static void smtp_rset_handler(void);
+
+/*************************************************
+* Recheck synchronization *
+*************************************************/
+
+/* Synchronization checks can never be perfect because a packet may be on its
+way but not arrived when the check is done. Normally, the checks happen when
+commands are read: Exim ensures that there is no more input in the input buffer.
+In normal cases, the response to the command will be fast, and there is no
+further check.
+
+However, for some commands an ACL is run, and that can include delays. In those
+cases, it is useful to do another check on the input just before sending the
+response. This also applies at the start of a connection. This function does
+that check by means of the select() function, as long as the facility is not
+disabled or inappropriate. A failure of select() is ignored.
+
+When there is unwanted input, we read it so that it appears in the log of the
+error.
+
+Arguments: none
+Returns: TRUE if all is well; FALSE if there is input pending
+*/
+
+static BOOL
+wouldblock_reading(void)
+{
+int fd, rc;
+fd_set fds;
+struct timeval tzero;
+
+#ifndef DISABLE_TLS
+if (tls_in.active.sock >= 0)
+ return !tls_could_read();
+#endif
+
+if (smtp_inptr < smtp_inend)
+ return FALSE;
+
+fd = fileno(smtp_in);
+FD_ZERO(&fds);
+FD_SET(fd, &fds);
+tzero.tv_sec = 0;
+tzero.tv_usec = 0;
+rc = select(fd + 1, (SELECT_ARG2_TYPE *)&fds, NULL, NULL, &tzero);
+
+if (rc <= 0) return TRUE; /* Not ready to read */
+rc = smtp_getc(GETC_BUFFER_UNLIMITED);
+if (rc < 0) return TRUE; /* End of file or error */
+
+smtp_ungetc(rc);
+return FALSE;
+}
+
+static BOOL
+check_sync(void)
+{
+if (!smtp_enforce_sync || !sender_host_address || f.sender_host_notsocket)
+ return TRUE;
+
+return wouldblock_reading();
+}
+
+
+/* If there's input waiting (and we're doing pipelineing) then we can pipeline
+a reponse with the one following. */
+
+static BOOL
+pipeline_response(void)
+{
+if ( !smtp_enforce_sync || !sender_host_address
+ || f.sender_host_notsocket || !f.smtp_in_pipelining_advertised)
+ return FALSE;
+
+if (wouldblock_reading()) return FALSE;
+f.smtp_in_pipelining_used = TRUE;
+return TRUE;
+}
+
+
+#ifdef SUPPORT_PIPE_CONNECT
+static BOOL
+pipeline_connect_sends(void)
+{
+if (!sender_host_address || f.sender_host_notsocket || !fl.pipe_connect_acceptable)
+ return FALSE;
+
+if (wouldblock_reading()) return FALSE;
+f.smtp_in_early_pipe_used = TRUE;
+return TRUE;
+}
+#endif
+
+/*************************************************
+* Log incomplete transactions *
+*************************************************/
+
+/* This function is called after a transaction has been aborted by RSET, QUIT,
+connection drops or other errors. It logs the envelope information received
+so far in order to preserve address verification attempts.
+
+Argument: string to indicate what aborted the transaction
+Returns: nothing
+*/
+
+static void
+incomplete_transaction_log(uschar *what)
+{
+if (!sender_address /* No transaction in progress */
+ || !LOGGING(smtp_incomplete_transaction))
+ return;
+
+/* Build list of recipients for logging */
+
+if (recipients_count > 0)
+ {
+ raw_recipients = store_get(recipients_count * sizeof(uschar *), FALSE);
+ for (int i = 0; i < recipients_count; i++)
+ raw_recipients[i] = recipients_list[i].address;
+ raw_recipients_count = recipients_count;
+ }
+
+log_write(L_smtp_incomplete_transaction, LOG_MAIN|LOG_SENDER|LOG_RECIPIENTS,
+ "%s incomplete transaction (%s)", host_and_ident(TRUE), what);
+}
+
+
+
+
+void
+smtp_command_timeout_exit(void)
+{
+log_write(L_lost_incoming_connection,
+ LOG_MAIN, "SMTP command timeout on%s connection from %s",
+ tls_in.active.sock >= 0 ? " TLS" : "", host_and_ident(FALSE));
+if (smtp_batched_input)
+ moan_smtp_batch(NULL, "421 SMTP command timeout"); /* Does not return */
+smtp_notquit_exit(US"command-timeout", US"421",
+ US"%s: SMTP command timeout - closing connection",
+ smtp_active_hostname);
+exim_exit(EXIT_FAILURE, US"receiving");
+}
+
+void
+smtp_command_sigterm_exit(void)
+{
+log_write(0, LOG_MAIN, "%s closed after SIGTERM", smtp_get_connection_info());
+if (smtp_batched_input)
+ moan_smtp_batch(NULL, "421 SIGTERM received"); /* Does not return */
+smtp_notquit_exit(US"signal-exit", US"421",
+ US"%s: Service not available - closing connection", smtp_active_hostname);
+exim_exit(EXIT_FAILURE, US"receiving");
+}
+
+void
+smtp_data_timeout_exit(void)
+{
+log_write(L_lost_incoming_connection,
+ LOG_MAIN, "SMTP data timeout (message abandoned) on connection from %s F=<%s>",
+ sender_fullhost ? sender_fullhost : US"local process", sender_address);
+receive_bomb_out(US"data-timeout", US"SMTP incoming data timeout");
+/* Does not return */
+}
+
+void
+smtp_data_sigint_exit(void)
+{
+log_write(0, LOG_MAIN, "%s closed after %s",
+ smtp_get_connection_info(), had_data_sigint == SIGTERM ? "SIGTERM":"SIGINT");
+receive_bomb_out(US"signal-exit",
+ US"Service not available - SIGTERM or SIGINT received");
+/* Does not return */
+}
+
+
+
+/* Refill the buffer, and notify DKIM verification code.
+Return false for error or EOF.
+*/
+
+static BOOL
+smtp_refill(unsigned lim)
+{
+int rc, save_errno;
+if (!smtp_out) return FALSE;
+fflush(smtp_out);
+if (smtp_receive_timeout > 0) ALARM(smtp_receive_timeout);
+
+/* Limit amount read, so non-message data is not fed to DKIM.
+Take care to not touch the safety NUL at the end of the buffer. */
+
+rc = read(fileno(smtp_in), smtp_inbuffer, MIN(IN_BUFFER_SIZE-1, lim));
+save_errno = errno;
+if (smtp_receive_timeout > 0) ALARM_CLR(0);
+if (rc <= 0)
+ {
+ /* Must put the error text in fixed store, because this might be during
+ header reading, where it releases unused store above the header. */
+ if (rc < 0)
+ {
+ if (had_command_timeout) /* set by signal handler */
+ smtp_command_timeout_exit(); /* does not return */
+ if (had_command_sigterm)
+ smtp_command_sigterm_exit();
+ if (had_data_timeout)
+ smtp_data_timeout_exit();
+ if (had_data_sigint)
+ smtp_data_sigint_exit();
+
+ smtp_had_error = save_errno;
+ smtp_read_error = string_copy_perm(
+ string_sprintf(" (error: %s)", strerror(save_errno)), FALSE);
+ }
+ else
+ smtp_had_eof = 1;
+ return FALSE;
+ }
+#ifndef DISABLE_DKIM
+dkim_exim_verify_feed(smtp_inbuffer, rc);
+#endif
+smtp_inend = smtp_inbuffer + rc;
+smtp_inptr = smtp_inbuffer;
+return TRUE;
+}
+
/*************************************************
* SMTP version of getc() *
*************************************************/
/* This gets the next byte from the SMTP input buffer. If the buffer is empty,
it flushes the output, and refills the buffer, with a timeout. The signal
handler is set appropriately by the calling function. This function is not used
-after a connection has negotated itself into an TLS/SSL state.
+after a connection has negotiated itself into an TLS/SSL state.
-Arguments: none
+Arguments: lim Maximum amount to read/buffer
Returns: the next character or EOF
*/
int
-smtp_getc(void)
+smtp_getc(unsigned lim)
+{
+if (smtp_inptr >= smtp_inend)
+ if (!smtp_refill(lim))
+ return EOF;
+return *smtp_inptr++;
+}
+
+uschar *
+smtp_getbuf(unsigned * len)
{
+unsigned size;
+uschar * buf;
+
if (smtp_inptr >= smtp_inend)
+ if (!smtp_refill(*len))
+ { *len = 0; return NULL; }
+
+if ((size = smtp_inend - smtp_inptr) > *len) size = *len;
+buf = smtp_inptr;
+smtp_inptr += size;
+*len = size;
+return buf;
+}
+
+void
+smtp_get_cache(void)
+{
+#ifndef DISABLE_DKIM
+int n = smtp_inend - smtp_inptr;
+if (n > 0)
+ dkim_exim_verify_feed(smtp_inptr, n);
+#endif
+}
+
+
+/* Get a byte from the smtp input, in CHUNKING mode. Handle ack of the
+previous BDAT chunk and getting new ones when we run out. Uses the
+underlying smtp_getc or tls_getc both for that and for getting the
+(buffered) data byte. EOD signals (an expected) no further data.
+ERR signals a protocol error, and EOF a closed input stream.
+
+Called from read_bdat_smtp() in receive.c for the message body, but also
+by the headers read loop in receive_msg(); manipulates chunking_state
+to handle the BDAT command/response.
+Placed here due to the correlation with the above smtp_getc(), which it wraps,
+and also by the need to do smtp command/response handling.
+
+Arguments: lim (ignored)
+Returns: the next character or ERR, EOD or EOF
+*/
+
+int
+bdat_getc(unsigned lim)
+{
+uschar * user_msg = NULL;
+uschar * log_msg;
+
+for(;;)
{
- int rc, save_errno;
- fflush(smtp_out);
- if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout);
- rc = read(fileno(smtp_in), smtp_inbuffer, in_buffer_size);
- save_errno = errno;
- alarm(0);
- if (rc <= 0)
+#ifndef DISABLE_DKIM
+ unsigned dkim_save;
+#endif
+
+ if (chunking_data_left > 0)
+ return lwr_receive_getc(chunking_data_left--);
+
+ receive_getc = lwr_receive_getc;
+ receive_getbuf = lwr_receive_getbuf;
+ receive_ungetc = lwr_receive_ungetc;
+#ifndef DISABLE_DKIM
+ dkim_save = dkim_collect_input;
+ dkim_collect_input = 0;
+#endif
+
+ /* Unless PIPELINING was offered, there should be no next command
+ until after we ack that chunk */
+
+ if (!f.smtp_in_pipelining_advertised && !check_sync())
+ {
+ unsigned n = smtp_inend - smtp_inptr;
+ if (n > 32) n = 32;
+
+ incomplete_transaction_log(US"sync failure");
+ log_write(0, LOG_MAIN|LOG_REJECT, "SMTP protocol synchronization error "
+ "(next input sent too soon: pipelining was not advertised): "
+ "rejected \"%s\" %s next input=\"%s\"%s",
+ smtp_cmd_buffer, host_and_ident(TRUE),
+ string_printing(string_copyn(smtp_inptr, n)),
+ smtp_inend - smtp_inptr > n ? "..." : "");
+ (void) synprot_error(L_smtp_protocol_error, 554, NULL,
+ US"SMTP synchronization error");
+ goto repeat_until_rset;
+ }
+
+ /* If not the last, ack the received chunk. The last response is delayed
+ until after the data ACL decides on it */
+
+ if (chunking_state == CHUNKING_LAST)
+ {
+#ifndef DISABLE_DKIM
+ dkim_exim_verify_feed(NULL, 0); /* notify EOD */
+#endif
+ return EOD;
+ }
+
+ smtp_printf("250 %u byte chunk received\r\n", FALSE, chunking_datasize);
+ chunking_state = CHUNKING_OFFERED;
+ DEBUG(D_receive) debug_printf("chunking state %d\n", (int)chunking_state);
+
+ /* Expect another BDAT cmd from input. RFC 3030 says nothing about
+ QUIT, RSET or NOOP but handling them seems obvious */
+
+next_cmd:
+ switch(smtp_read_command(TRUE, 1))
{
- /* Must put the error text in fixed store, because this might be during
- header reading, where it releases unused store above the header. */
- if (rc < 0)
+ default:
+ (void) synprot_error(L_smtp_protocol_error, 503, NULL,
+ US"only BDAT permissible after non-LAST BDAT");
+
+ repeat_until_rset:
+ switch(smtp_read_command(TRUE, 1))
+ {
+ case QUIT_CMD: smtp_quit_handler(&user_msg, &log_msg); /*FALLTHROUGH */
+ case EOF_CMD: return EOF;
+ case RSET_CMD: smtp_rset_handler(); return ERR;
+ default: if (synprot_error(L_smtp_protocol_error, 503, NULL,
+ US"only RSET accepted now") > 0)
+ return EOF;
+ goto repeat_until_rset;
+ }
+
+ case QUIT_CMD:
+ smtp_quit_handler(&user_msg, &log_msg);
+ /*FALLTHROUGH*/
+ case EOF_CMD:
+ return EOF;
+
+ case RSET_CMD:
+ smtp_rset_handler();
+ return ERR;
+
+ case NOOP_CMD:
+ HAD(SCH_NOOP);
+ smtp_printf("250 OK\r\n", FALSE);
+ goto next_cmd;
+
+ case BDAT_CMD:
{
- smtp_had_error = save_errno;
- smtp_read_error = string_copy_malloc(
- string_sprintf(" (error: %s)", strerror(save_errno)));
+ int n;
+
+ if (sscanf(CS smtp_cmd_data, "%u %n", &chunking_datasize, &n) < 1)
+ {
+ (void) synprot_error(L_smtp_protocol_error, 501, NULL,
+ US"missing size for BDAT command");
+ return ERR;
+ }
+ chunking_state = strcmpic(smtp_cmd_data+n, US"LAST") == 0
+ ? CHUNKING_LAST : CHUNKING_ACTIVE;
+ chunking_data_left = chunking_datasize;
+ DEBUG(D_receive) debug_printf("chunking state %d, %d bytes\n",
+ (int)chunking_state, chunking_data_left);
+
+ if (chunking_datasize == 0)
+ if (chunking_state == CHUNKING_LAST)
+ return EOD;
+ else
+ {
+ (void) synprot_error(L_smtp_protocol_error, 504, NULL,
+ US"zero size for BDAT command");
+ goto repeat_until_rset;
+ }
+
+ receive_getc = bdat_getc;
+ receive_getbuf = bdat_getbuf; /* r~getbuf is never actually used */
+ receive_ungetc = bdat_ungetc;
+#ifndef DISABLE_DKIM
+ dkim_collect_input = dkim_save;
+#endif
+ break; /* to top of main loop */
}
- else smtp_had_eof = 1;
- return EOF;
}
- smtp_inend = smtp_inbuffer + rc;
- smtp_inptr = smtp_inbuffer;
}
-return *smtp_inptr++;
+}
+
+uschar *
+bdat_getbuf(unsigned * len)
+{
+uschar * buf;
+
+if (chunking_data_left <= 0)
+ { *len = 0; return NULL; }
+
+if (*len > chunking_data_left) *len = chunking_data_left;
+buf = lwr_receive_getbuf(len); /* Either smtp_getbuf or tls_getbuf */
+chunking_data_left -= *len;
+return buf;
+}
+
+void
+bdat_flush_data(void)
+{
+while (chunking_data_left)
+ {
+ unsigned n = chunking_data_left;
+ if (!bdat_getbuf(&n)) break;
+ }
+
+receive_getc = lwr_receive_getc;
+receive_getbuf = lwr_receive_getbuf;
+receive_ungetc = lwr_receive_ungetc;
+
+if (chunking_state != CHUNKING_LAST)
+ {
+ chunking_state = CHUNKING_OFFERED;
+ DEBUG(D_receive) debug_printf("chunking state %d\n", (int)chunking_state);
+ }
}
+
/*************************************************
* SMTP version of ungetc() *
*************************************************/
int
smtp_ungetc(int ch)
{
-*(--smtp_inptr) = ch;
+*--smtp_inptr = ch;
return ch;
}
+int
+bdat_ungetc(int ch)
+{
+chunking_data_left++;
+return lwr_receive_ungetc(ch);
+}
+
/*************************************************
+/*************************************************
+* Test for characters in the SMTP buffer *
+*************************************************/
+
+/* Used at the end of a message
+
+Arguments: none
+Returns: TRUE/FALSE
+*/
+
+BOOL
+smtp_buffered(void)
+{
+return smtp_inptr < smtp_inend;
+}
+
+
/*************************************************
* Write formatted string to SMTP channel *
Arguments:
format format string
+ more further data expected
... optional arguments
Returns: nothing
*/
void
-smtp_printf(char *format, ...)
+smtp_printf(const char *format, BOOL more, ...)
{
va_list ap;
+va_start(ap, more);
+smtp_vprintf(format, more, ap);
+va_end(ap);
+}
+
+/* This is split off so that verify.c:respond_printf() can, in effect, call
+smtp_printf(), bearing in mind that in C a vararg function can't directly
+call another vararg function, only a function which accepts a va_list. */
+/*XXX consider passing caller-info in, for string_vformat-onward */
+
+void
+smtp_vprintf(const char *format, BOOL more, va_list ap)
+{
+gstring gs = { .size = big_buffer_size, .ptr = 0, .s = big_buffer };
+BOOL yield;
+
+/* Use taint-unchecked routines for writing into big_buffer, trusting
+that we'll never expand it. */
+
+yield = !! string_vformat(&gs, SVFMT_TAINT_NOCHK, format, ap);
+string_from_gstring(&gs);
+
DEBUG(D_receive)
{
- va_start(ap, format);
- (void) string_vformat(big_buffer, big_buffer_size, format, ap);
- debug_printf("SMTP>> %s", big_buffer);
+ uschar *msg_copy, *cr, *end;
+ msg_copy = string_copy(gs.s);
+ end = msg_copy + gs.ptr;
+ while ((cr = Ustrchr(msg_copy, '\r')) != NULL) /* lose CRs */
+ memmove(cr, cr + 1, (end--) - cr);
+ debug_printf("SMTP>> %s", msg_copy);
}
-va_start(ap, format);
+if (!yield)
+ {
+ log_write(0, LOG_MAIN|LOG_PANIC, "string too large in smtp_printf()");
+ smtp_closedown(US"Unexpected error");
+ exim_exit(EXIT_FAILURE, NULL);
+ }
-/* If in a TLS session we have to format the string, and then write it using a
-TLS function. */
+/* If this is the first output for a (non-batch) RCPT command, see if all RCPTs
+have had the same. Note: this code is also present in smtp_respond(). It would
+be tidier to have it only in one place, but when it was added, it was easier to
+do it that way, so as not to have to mess with the code for the RCPT command,
+which sometimes uses smtp_printf() and sometimes smtp_respond(). */
-#ifdef SUPPORT_TLS
-if (tls_active >= 0)
+if (fl.rcpt_in_progress)
{
- if (!string_vformat(big_buffer, big_buffer_size, format, ap))
- {
- log_write(0, LOG_MAIN|LOG_PANIC, "string too large in smtp_printf");
- smtp_closedown(US"Unexpected error");
- exim_exit(EXIT_FAILURE);
- }
- if (tls_write(big_buffer, Ustrlen(big_buffer)) < 0) smtp_write_error = -1;
+ if (rcpt_smtp_response == NULL)
+ rcpt_smtp_response = string_copy(big_buffer);
+ else if (fl.rcpt_smtp_response_same &&
+ Ustrcmp(rcpt_smtp_response, big_buffer) != 0)
+ fl.rcpt_smtp_response_same = FALSE;
+ fl.rcpt_in_progress = FALSE;
+ }
+
+/* Now write the string */
+
+#ifndef DISABLE_TLS
+if (tls_in.active.sock >= 0)
+ {
+ if (tls_write(NULL, gs.s, gs.ptr, more) < 0)
+ smtp_write_error = -1;
}
else
#endif
-/* Otherwise, just use the standard library function. */
-
-if (vfprintf(smtp_out, format, ap) < 0) smtp_write_error = -1;
-va_end(ap);
+if (fprintf(smtp_out, "%s", gs.s) < 0) smtp_write_error = -1;
}
int
smtp_fflush(void)
{
-if (tls_active < 0 && fflush(smtp_out) != 0) smtp_write_error = -1;
+if (tls_in.active.sock < 0 && fflush(smtp_out) != 0) smtp_write_error = -1;
return smtp_write_error;
}
static void
command_timeout_handler(int sig)
{
-sig = sig; /* Keep picky compilers happy */
-log_write(L_lost_incoming_connection,
- LOG_MAIN, "SMTP command timeout on%s connection from %s",
- (tls_active >= 0)? " TLS" : "",
- host_and_ident(FALSE));
-if (smtp_batched_input)
- moan_smtp_batch(NULL, "421 SMTP command timeout"); /* Does not return */
-smtp_printf("421 %s: SMTP command timeout - closing connection\r\n",
- smtp_active_hostname);
-mac_smtp_fflush();
-exim_exit(EXIT_FAILURE);
+had_command_timeout = sig;
}
static void
command_sigterm_handler(int sig)
{
-sig = sig; /* Keep picky compilers happy */
-log_write(0, LOG_MAIN, "%s closed after SIGTERM", smtp_get_connection_info());
-if (smtp_batched_input)
- moan_smtp_batch(NULL, "421 SIGTERM received"); /* Does not return */
-smtp_printf("421 %s: Service not available - closing connection\r\n",
- smtp_active_hostname);
-exim_exit(EXIT_FAILURE);
+had_command_sigterm = sig;
+}
+
+
+
+
+#ifdef SUPPORT_PROXY
+/*************************************************
+* Restore socket timeout to previous value *
+*************************************************/
+/* If the previous value was successfully retrieved, restore
+it before returning control to the non-proxy routines
+
+Arguments: fd - File descriptor for input
+ get_ok - Successfully retrieved previous values
+ tvtmp - Time struct with previous values
+ vslen - Length of time struct
+Returns: none
+*/
+static void
+restore_socket_timeout(int fd, int get_ok, struct timeval * tvtmp, socklen_t vslen)
+{
+if (get_ok == 0)
+ (void) setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, CS tvtmp, vslen);
+}
+
+/*************************************************
+* Check if host is required proxy host *
+*************************************************/
+/* The function determines if inbound host will be a regular smtp host
+or if it is configured that it must use Proxy Protocol. A local
+connection cannot.
+
+Arguments: none
+Returns: bool
+*/
+
+static BOOL
+check_proxy_protocol_host()
+{
+int rc;
+
+if ( sender_host_address
+ && (rc = verify_check_this_host(CUSS &hosts_proxy, NULL, NULL,
+ sender_host_address, NULL)) == OK)
+ {
+ DEBUG(D_receive)
+ debug_printf("Detected proxy protocol configured host\n");
+ proxy_session = TRUE;
+ }
+return proxy_session;
+}
+
+
+/*************************************************
+* Read data until newline or end of buffer *
+*************************************************/
+/* While SMTP is server-speaks-first, TLS is client-speaks-first, so we can't
+read an entire buffer and assume there will be nothing past a proxy protocol
+header. Our approach normally is to use stdio, but again that relies upon
+"STARTTLS\r\n" and a server response before the client starts TLS handshake, or
+reading _nothing_ before client TLS handshake. So we don't want to use the
+usual buffering reads which may read enough to block TLS starting.
+
+So unfortunately we're down to "read one byte at a time, with a syscall each,
+and expect a little overhead", for all proxy-opened connections which are v1,
+just to handle the TLS-on-connect case. Since SSL functions wrap the
+underlying fd, we can't assume that we can feed them any already-read content.
+
+We need to know where to read to, the max capacity, and we'll read until we
+get a CR and one more character. Let the caller scream if it's CR+!LF.
+
+Return the amount read.
+*/
+
+static int
+swallow_until_crlf(int fd, uschar *base, int already, int capacity)
+{
+uschar *to = base + already;
+uschar *cr;
+int have = 0;
+int ret;
+int last = 0;
+
+/* For "PROXY UNKNOWN\r\n" we, at time of writing, expect to have read
+up through the \r; for the _normal_ case, we haven't yet seen the \r. */
+
+cr = memchr(base, '\r', already);
+if (cr != NULL)
+ {
+ if ((cr - base) < already - 1)
+ {
+ /* \r and presumed \n already within what we have; probably not
+ actually proxy protocol, but abort cleanly. */
+ return 0;
+ }
+ /* \r is last character read, just need one more. */
+ last = 1;
+ }
+
+while (capacity > 0)
+ {
+ do { ret = recv(fd, to, 1, 0); } while (ret == -1 && errno == EINTR);
+ if (ret == -1)
+ return -1;
+ have++;
+ if (last)
+ return have;
+ if (*to == '\r')
+ last = 1;
+ capacity--;
+ to++;
+ }
+
+/* reached end without having room for a final newline, abort */
+errno = EOVERFLOW;
+return -1;
}
+/*************************************************
+* Setup host for proxy protocol *
+*************************************************/
+/* The function configures the connection based on a header from the
+inbound host to use Proxy Protocol. The specification is very exact
+so exit with an error if do not find the exact required pieces. This
+includes an incorrect number of spaces separating args.
+
+Arguments: none
+Returns: Boolean success
+*/
+
+static void
+setup_proxy_protocol_host()
+{
+union {
+ struct {
+ uschar line[108];
+ } v1;
+ struct {
+ uschar sig[12];
+ uint8_t ver_cmd;
+ uint8_t fam;
+ uint16_t len;
+ union {
+ struct { /* TCP/UDP over IPv4, len = 12 */
+ uint32_t src_addr;
+ uint32_t dst_addr;
+ uint16_t src_port;
+ uint16_t dst_port;
+ } ip4;
+ struct { /* TCP/UDP over IPv6, len = 36 */
+ uint8_t src_addr[16];
+ uint8_t dst_addr[16];
+ uint16_t src_port;
+ uint16_t dst_port;
+ } ip6;
+ struct { /* AF_UNIX sockets, len = 216 */
+ uschar src_addr[108];
+ uschar dst_addr[108];
+ } unx;
+ } addr;
+ } v2;
+} hdr;
+
+/* Temp variables used in PPv2 address:port parsing */
+uint16_t tmpport;
+char tmpip[INET_ADDRSTRLEN];
+struct sockaddr_in tmpaddr;
+char tmpip6[INET6_ADDRSTRLEN];
+struct sockaddr_in6 tmpaddr6;
+
+/* We can't read "all data until end" because while SMTP is
+server-speaks-first, the TLS handshake is client-speaks-first, so for
+TLS-on-connect ports the proxy protocol header will usually be immediately
+followed by a TLS handshake, and with N TLS libraries, we can't reliably
+reinject data for reading by those. So instead we first read "enough to be
+safely read within the header, and figure out how much more to read".
+For v1 we will later read to the end-of-line, for v2 we will read based upon
+the stated length.
+
+The v2 sig is 12 octets, and another 4 gets us the length, so we know how much
+data is needed total. For v1, where the line looks like:
+PROXY TCPn L3src L3dest SrcPort DestPort \r\n
+
+However, for v1 there's also `PROXY UNKNOWN\r\n` which is only 15 octets.
+We seem to support that. So, if we read 14 octets then we can tell if we're
+v2 or v1. If we're v1, we can continue reading as normal.
+
+If we're v2, we can't slurp up the entire header. We need the length in the
+15th & 16th octets, then to read everything after that.
+
+So to safely handle v1 and v2, with client-sent-first supported correctly,
+we have to do a minimum of 3 read calls, not 1. Eww.
+*/
+
+#define PROXY_INITIAL_READ 14
+#define PROXY_V2_HEADER_SIZE 16
+#if PROXY_INITIAL_READ > PROXY_V2_HEADER_SIZE
+# error Code bug in sizes of data to read for proxy usage
+#endif
+
+int get_ok = 0;
+int size, ret;
+int fd = fileno(smtp_in);
+const char v2sig[12] = "\x0D\x0A\x0D\x0A\x00\x0D\x0A\x51\x55\x49\x54\x0A";
+uschar * iptype; /* To display debug info */
+struct timeval tv;
+struct timeval tvtmp;
+socklen_t vslen = sizeof(struct timeval);
+BOOL yield = FALSE;
+
+/* Save current socket timeout values */
+get_ok = getsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, CS &tvtmp, &vslen);
+
+/* Proxy Protocol host must send header within a short time
+(default 3 seconds) or it's considered invalid */
+tv.tv_sec = PROXY_NEGOTIATION_TIMEOUT_SEC;
+tv.tv_usec = PROXY_NEGOTIATION_TIMEOUT_USEC;
+if (setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, CS &tv, sizeof(tv)) < 0)
+ goto bad;
+
+do
+ {
+ /* The inbound host was declared to be a Proxy Protocol host, so
+ don't do a PEEK into the data, actually slurp up enough to be
+ "safe". Can't take it all because TLS-on-connect clients follow
+ immediately with TLS handshake. */
+ ret = recv(fd, &hdr, PROXY_INITIAL_READ, 0);
+ }
+ while (ret == -1 && errno == EINTR);
+
+if (ret == -1)
+ goto proxyfail;
+
+/* For v2, handle reading the length, and then the rest. */
+if ((ret == PROXY_INITIAL_READ) && (memcmp(&hdr.v2, v2sig, sizeof(v2sig)) == 0))
+ {
+ int retmore;
+ uint8_t ver;
+
+ /* First get the length fields. */
+ do
+ {
+ retmore = recv(fd, (uschar*)&hdr + ret, PROXY_V2_HEADER_SIZE - PROXY_INITIAL_READ, 0);
+ } while (retmore == -1 && errno == EINTR);
+ if (retmore == -1)
+ goto proxyfail;
+ ret += retmore;
+
+ ver = (hdr.v2.ver_cmd & 0xf0) >> 4;
+
+ /* May 2014: haproxy combined the version and command into one byte to
+ allow two full bytes for the length field in order to proxy SSL
+ connections. SSL Proxy is not supported in this version of Exim, but
+ must still separate values here. */
+
+ if (ver != 0x02)
+ {
+ DEBUG(D_receive) debug_printf("Invalid Proxy Protocol version: %d\n", ver);
+ goto proxyfail;
+ }
+
+ /* The v2 header will always be 16 bytes per the spec. */
+ size = 16 + ntohs(hdr.v2.len);
+ DEBUG(D_receive) debug_printf("Detected PROXYv2 header, size %d (limit %d)\n",
+ size, (int)sizeof(hdr));
+
+ /* We should now have 16 octets (PROXY_V2_HEADER_SIZE), and we know the total
+ amount that we need. Double-check that the size is not unreasonable, then
+ get the rest. */
+ if (size > sizeof(hdr))
+ {
+ DEBUG(D_receive) debug_printf("PROXYv2 header size unreasonably large; security attack?\n");
+ goto proxyfail;
+ }
+
+ do
+ {
+ do
+ {
+ retmore = recv(fd, (uschar*)&hdr + ret, size-ret, 0);
+ } while (retmore == -1 && errno == EINTR);
+ if (retmore == -1)
+ goto proxyfail;
+ ret += retmore;
+ DEBUG(D_receive) debug_printf("PROXYv2: have %d/%d required octets\n", ret, size);
+ } while (ret < size);
+
+ } /* end scope for getting rest of data for v2 */
+
+/* At this point: if PROXYv2, we've read the exact size required for all data;
+if PROXYv1 then we've read "less than required for any valid line" and should
+read the rest". */
+
+if (ret >= 16 && memcmp(&hdr.v2, v2sig, 12) == 0)
+ {
+ uint8_t cmd = (hdr.v2.ver_cmd & 0x0f);
+
+ switch (cmd)
+ {
+ case 0x01: /* PROXY command */
+ switch (hdr.v2.fam)
+ {
+ case 0x11: /* TCPv4 address type */
+ iptype = US"IPv4";
+ tmpaddr.sin_addr.s_addr = hdr.v2.addr.ip4.src_addr;
+ inet_ntop(AF_INET, &tmpaddr.sin_addr, CS &tmpip, sizeof(tmpip));
+ if (!string_is_ip_address(US tmpip, NULL))
+ {
+ DEBUG(D_receive) debug_printf("Invalid %s source IP\n", iptype);
+ goto proxyfail;
+ }
+ proxy_local_address = sender_host_address;
+ sender_host_address = string_copy(US tmpip);
+ tmpport = ntohs(hdr.v2.addr.ip4.src_port);
+ proxy_local_port = sender_host_port;
+ sender_host_port = tmpport;
+ /* Save dest ip/port */
+ tmpaddr.sin_addr.s_addr = hdr.v2.addr.ip4.dst_addr;
+ inet_ntop(AF_INET, &tmpaddr.sin_addr, CS &tmpip, sizeof(tmpip));
+ if (!string_is_ip_address(US tmpip, NULL))
+ {
+ DEBUG(D_receive) debug_printf("Invalid %s dest port\n", iptype);
+ goto proxyfail;
+ }
+ proxy_external_address = string_copy(US tmpip);
+ tmpport = ntohs(hdr.v2.addr.ip4.dst_port);
+ proxy_external_port = tmpport;
+ goto done;
+ case 0x21: /* TCPv6 address type */
+ iptype = US"IPv6";
+ memmove(tmpaddr6.sin6_addr.s6_addr, hdr.v2.addr.ip6.src_addr, 16);
+ inet_ntop(AF_INET6, &tmpaddr6.sin6_addr, CS &tmpip6, sizeof(tmpip6));
+ if (!string_is_ip_address(US tmpip6, NULL))
+ {
+ DEBUG(D_receive) debug_printf("Invalid %s source IP\n", iptype);
+ goto proxyfail;
+ }
+ proxy_local_address = sender_host_address;
+ sender_host_address = string_copy(US tmpip6);
+ tmpport = ntohs(hdr.v2.addr.ip6.src_port);
+ proxy_local_port = sender_host_port;
+ sender_host_port = tmpport;
+ /* Save dest ip/port */
+ memmove(tmpaddr6.sin6_addr.s6_addr, hdr.v2.addr.ip6.dst_addr, 16);
+ inet_ntop(AF_INET6, &tmpaddr6.sin6_addr, CS &tmpip6, sizeof(tmpip6));
+ if (!string_is_ip_address(US tmpip6, NULL))
+ {
+ DEBUG(D_receive) debug_printf("Invalid %s dest port\n", iptype);
+ goto proxyfail;
+ }
+ proxy_external_address = string_copy(US tmpip6);
+ tmpport = ntohs(hdr.v2.addr.ip6.dst_port);
+ proxy_external_port = tmpport;
+ goto done;
+ default:
+ DEBUG(D_receive)
+ debug_printf("Unsupported PROXYv2 connection type: 0x%02x\n",
+ hdr.v2.fam);
+ goto proxyfail;
+ }
+ /* Unsupported protocol, keep local connection address */
+ break;
+ case 0x00: /* LOCAL command */
+ /* Keep local connection address for LOCAL */
+ iptype = US"local";
+ break;
+ default:
+ DEBUG(D_receive)
+ debug_printf("Unsupported PROXYv2 command: 0x%x\n", cmd);
+ goto proxyfail;
+ }
+ }
+else if (ret >= 8 && memcmp(hdr.v1.line, "PROXY", 5) == 0)
+ {
+ uschar *p;
+ uschar *end;
+ uschar *sp; /* Utility variables follow */
+ int tmp_port;
+ int r2;
+ char *endc;
+
+ /* get the rest of the line */
+ r2 = swallow_until_crlf(fd, (uschar*)&hdr, ret, sizeof(hdr)-ret);
+ if (r2 == -1)
+ goto proxyfail;
+ ret += r2;
+
+ p = string_copy(hdr.v1.line);
+ end = memchr(p, '\r', ret - 1);
+
+ if (!end || (end == (uschar*)&hdr + ret) || end[1] != '\n')
+ {
+ DEBUG(D_receive) debug_printf("Partial or invalid PROXY header\n");
+ goto proxyfail;
+ }
+ *end = '\0'; /* Terminate the string */
+ size = end + 2 - p; /* Skip header + CRLF */
+ DEBUG(D_receive) debug_printf("Detected PROXYv1 header\n");
+ DEBUG(D_receive) debug_printf("Bytes read not within PROXY header: %d\n", ret - size);
+ /* Step through the string looking for the required fields. Ensure
+ strict adherence to required formatting, exit for any error. */
+ p += 5;
+ if (!isspace(*(p++)))
+ {
+ DEBUG(D_receive) debug_printf("Missing space after PROXY command\n");
+ goto proxyfail;
+ }
+ if (!Ustrncmp(p, CCS"TCP4", 4))
+ iptype = US"IPv4";
+ else if (!Ustrncmp(p,CCS"TCP6", 4))
+ iptype = US"IPv6";
+ else if (!Ustrncmp(p,CCS"UNKNOWN", 7))
+ {
+ iptype = US"Unknown";
+ goto done;
+ }
+ else
+ {
+ DEBUG(D_receive) debug_printf("Invalid TCP type\n");
+ goto proxyfail;
+ }
+
+ p += Ustrlen(iptype);
+ if (!isspace(*(p++)))
+ {
+ DEBUG(D_receive) debug_printf("Missing space after TCP4/6 command\n");
+ goto proxyfail;
+ }
+ /* Find the end of the arg */
+ if ((sp = Ustrchr(p, ' ')) == NULL)
+ {
+ DEBUG(D_receive)
+ debug_printf("Did not find proxied src %s\n", iptype);
+ goto proxyfail;
+ }
+ *sp = '\0';
+ if(!string_is_ip_address(p, NULL))
+ {
+ DEBUG(D_receive)
+ debug_printf("Proxied src arg is not an %s address\n", iptype);
+ goto proxyfail;
+ }
+ proxy_local_address = sender_host_address;
+ sender_host_address = p;
+ p = sp + 1;
+ if ((sp = Ustrchr(p, ' ')) == NULL)
+ {
+ DEBUG(D_receive)
+ debug_printf("Did not find proxy dest %s\n", iptype);
+ goto proxyfail;
+ }
+ *sp = '\0';
+ if(!string_is_ip_address(p, NULL))
+ {
+ DEBUG(D_receive)
+ debug_printf("Proxy dest arg is not an %s address\n", iptype);
+ goto proxyfail;
+ }
+ proxy_external_address = p;
+ p = sp + 1;
+ if ((sp = Ustrchr(p, ' ')) == NULL)
+ {
+ DEBUG(D_receive) debug_printf("Did not find proxied src port\n");
+ goto proxyfail;
+ }
+ *sp = '\0';
+ tmp_port = strtol(CCS p, &endc, 10);
+ if (*endc || tmp_port == 0)
+ {
+ DEBUG(D_receive)
+ debug_printf("Proxied src port '%s' not an integer\n", p);
+ goto proxyfail;
+ }
+ proxy_local_port = sender_host_port;
+ sender_host_port = tmp_port;
+ p = sp + 1;
+ if ((sp = Ustrchr(p, '\0')) == NULL)
+ {
+ DEBUG(D_receive) debug_printf("Did not find proxy dest port\n");
+ goto proxyfail;
+ }
+ tmp_port = strtol(CCS p, &endc, 10);
+ if (*endc || tmp_port == 0)
+ {
+ DEBUG(D_receive)
+ debug_printf("Proxy dest port '%s' not an integer\n", p);
+ goto proxyfail;
+ }
+ proxy_external_port = tmp_port;
+ /* Already checked for /r /n above. Good V1 header received. */
+ }
+else
+ {
+ /* Wrong protocol */
+ DEBUG(D_receive) debug_printf("Invalid proxy protocol version negotiation\n");
+ (void) swallow_until_crlf(fd, (uschar*)&hdr, ret, sizeof(hdr)-ret);
+ goto proxyfail;
+ }
+
+done:
+ DEBUG(D_receive)
+ debug_printf("Valid %s sender from Proxy Protocol header\n", iptype);
+ yield = proxy_session;
+
+/* Don't flush any potential buffer contents. Any input on proxyfail
+should cause a synchronization failure */
+
+proxyfail:
+ restore_socket_timeout(fd, get_ok, &tvtmp, vslen);
+
+bad:
+ if (yield)
+ {
+ sender_host_name = NULL;
+ (void) host_name_lookup();
+ host_build_sender_fullhost();
+ }
+ else
+ {
+ f.proxy_session_failed = TRUE;
+ DEBUG(D_receive)
+ debug_printf("Failure to extract proxied host, only QUIT allowed\n");
+ }
+return;
+}
+#endif
/*************************************************
* Read one command line *
There are sites that don't do this, and in any case internal SMTP probably
should check only for LF. Consequently, we check here for LF only. The line
ends up with [CR]LF removed from its end. If we get an overlong line, treat as
-an unknown command. The command is read into the static cmd_buffer.
+an unknown command. The command is read into the global smtp_cmd_buffer so that
+it is available via $smtp_command.
The character reading routine sets up a timeout for each block actually read
from the input (which may contain more than one command). We set up a special
return when it runs.
Arguments:
- check_sync if TRUE, check synchronization rules if global option is TRUE
+ check_sync if TRUE, check synchronization rules if global option is TRUE
+ buffer_lim maximum to buffer in lower layer
Returns: a code identifying the command (enumerated above)
*/
static int
-smtp_read_command(BOOL check_sync)
+smtp_read_command(BOOL check_sync, unsigned buffer_lim)
{
int c;
int ptr = 0;
-smtp_cmd_list *p;
BOOL hadnull = FALSE;
+had_command_timeout = 0;
os_non_restarting_signal(SIGALRM, command_timeout_handler);
-while ((c = (receive_getc)()) != '\n' && c != EOF)
+while ((c = (receive_getc)(buffer_lim)) != '\n' && c != EOF)
{
- if (ptr >= cmd_buffer_size)
+ if (ptr >= SMTP_CMD_BUFFER_SIZE)
{
os_non_restarting_signal(SIGALRM, sigalrm_handler);
return OTHER_CMD;
hadnull = TRUE;
c = '?';
}
- cmd_buffer[ptr++] = c;
+ smtp_cmd_buffer[ptr++] = c;
}
receive_linecount++; /* For BSMTP errors */
/* Remove any CR and white space at the end of the line, and terminate the
string. */
-while (ptr > 0 && isspace(cmd_buffer[ptr-1])) ptr--;
-cmd_buffer[ptr] = 0;
+while (ptr > 0 && isspace(smtp_cmd_buffer[ptr-1])) ptr--;
+smtp_cmd_buffer[ptr] = 0;
-DEBUG(D_receive) debug_printf("SMTP<< %s\n", cmd_buffer);
+DEBUG(D_receive) debug_printf("SMTP<< %s\n", smtp_cmd_buffer);
/* NULLs are not allowed in SMTP commands */
to the start of the actual data characters. Check for SMTP synchronization
if required. */
-for (p = cmd_list; p < cmd_list_end; p++)
+for (smtp_cmd_list * p = cmd_list; p < cmd_list_end; p++)
{
- if (strncmpic(cmd_buffer, US p->name, p->len) == 0)
+#ifdef SUPPORT_PROXY
+ /* Only allow QUIT command if Proxy Protocol parsing failed */
+ if (proxy_session && f.proxy_session_failed && p->cmd != QUIT_CMD)
+ continue;
+#endif
+ if ( p->len
+ && strncmpic(smtp_cmd_buffer, US p->name, p->len) == 0
+ && ( smtp_cmd_buffer[p->len-1] == ':' /* "mail from:" or "rcpt to:" */
+ || smtp_cmd_buffer[p->len] == 0
+ || smtp_cmd_buffer[p->len] == ' '
+ ) )
{
if (smtp_inptr < smtp_inend && /* Outstanding input */
p->cmd < sync_cmd_limit && /* Command should sync */
check_sync && /* Local flag set */
smtp_enforce_sync && /* Global flag set */
sender_host_address != NULL && /* Not local input */
- !sender_host_notsocket) /* Really is a socket */
+ !f.sender_host_notsocket) /* Really is a socket */
return BADSYN_CMD;
- /* Point after the command, but don't skip over leading spaces till after
- the following test, so that if it fails, the command name can easily be
- logged. */
+ /* The variables $smtp_command and $smtp_command_argument point into the
+ unmodified input buffer. A copy of the latter is taken for actual
+ processing, so that it can be chopped up into separate parts if necessary,
+ for example, when processing a MAIL command options such as SIZE that can
+ follow the sender address. */
- smtp_command_argument = cmd_buffer + p->len;
+ smtp_cmd_argument = smtp_cmd_buffer + p->len;
+ while (isspace(*smtp_cmd_argument)) smtp_cmd_argument++;
+ Ustrcpy(smtp_data_buffer, smtp_cmd_argument);
+ smtp_cmd_data = smtp_data_buffer;
/* Count non-mail commands from those hosts that are controlled in this
way. The default is all hosts. We don't waste effort checking the list
return TOO_MANY_NONMAIL_CMD;
}
- /* Get the data pointer over leading spaces and return; if there is data
- for a command that does not expect it, give the error centrally here. */
+ /* If there is data for a command that does not expect it, generate the
+ error here. */
- while (isspace(*smtp_command_argument)) smtp_command_argument++;
- return (p->has_arg || *smtp_command_argument == 0)? p->cmd : BADARG_CMD;
+ return (p->has_arg || *smtp_cmd_data == 0)? p->cmd : BADARG_CMD;
}
}
+#ifdef SUPPORT_PROXY
+/* Only allow QUIT command if Proxy Protocol parsing failed */
+if (proxy_session && f.proxy_session_failed)
+ return PROXY_FAIL_IGNORE_CMD;
+#endif
+
/* Enforce synchronization for unknown commands */
-if (smtp_inptr < smtp_inend && /* Outstanding input */
- check_sync && /* Local flag set */
- smtp_enforce_sync && /* Global flag set */
- sender_host_address != NULL && /* Not local input */
- !sender_host_notsocket) /* Really is a socket */
+if ( smtp_inptr < smtp_inend /* Outstanding input */
+ && check_sync /* Local flag set */
+ && smtp_enforce_sync /* Global flag set */
+ && sender_host_address /* Not local input */
+ && !f.sender_host_notsocket) /* Really is a socket */
return BADSYN_CMD;
return OTHER_CMD;
except QUIT. The existence of an SMTP call is detected by the non-NULLness of
smtp_in.
-Argument: SMTP reply string to send, excluding the code
+Arguments:
+ message SMTP reply string to send, excluding the code
+
Returns: nothing
*/
void
smtp_closedown(uschar *message)
{
-if (smtp_in == NULL || smtp_batched_input) return;
+if (!smtp_in || smtp_batched_input) return;
receive_swallow_smtp();
-smtp_printf("421 %s\r\n", message);
+smtp_printf("421 %s\r\n", FALSE, message);
-for (;;)
+for (;;) switch(smtp_read_command(FALSE, GETC_BUFFER_UNLIMITED))
{
- switch(smtp_read_command(FALSE))
- {
- case EOF_CMD:
+ case EOF_CMD:
return;
- case QUIT_CMD:
- smtp_printf("221 %s closing connection\r\n", smtp_active_hostname);
+ case QUIT_CMD:
+ smtp_printf("221 %s closing connection\r\n", FALSE, smtp_active_hostname);
mac_smtp_fflush();
return;
- case RSET_CMD:
- smtp_printf("250 Reset OK\r\n");
+ case RSET_CMD:
+ smtp_printf("250 Reset OK\r\n", FALSE);
break;
- default:
- smtp_printf("421 %s\r\n", message);
+ default:
+ smtp_printf("421 %s\r\n", FALSE, message);
break;
- }
}
}
/* This function is called when logging information about an SMTP connection.
It sets up appropriate source information, depending on the type of connection.
+If sender_fullhost is NULL, we are at a very early stage of the connection;
+just use the IP address.
Argument: none
Returns: a string describing the connection
uschar *
smtp_get_connection_info(void)
{
+const uschar * hostname = sender_fullhost
+ ? sender_fullhost : sender_host_address;
+
if (host_checking)
- return string_sprintf("SMTP connection from %s", sender_fullhost);
+ return string_sprintf("SMTP connection from %s", hostname);
-if (sender_host_unknown || sender_host_notsocket)
+if (f.sender_host_unknown || f.sender_host_notsocket)
return string_sprintf("SMTP connection from %s", sender_ident);
-if (is_inetd)
- return string_sprintf("SMTP connection from %s (via inetd)", sender_fullhost);
+if (f.is_inetd)
+ return string_sprintf("SMTP connection from %s (via inetd)", hostname);
-if ((log_extra_selector & LX_incoming_interface) != 0 &&
- interface_address != NULL)
- return string_sprintf("SMTP connection from %s I=[%s]:%d", sender_fullhost,
+if (LOGGING(incoming_interface) && interface_address)
+ return string_sprintf("SMTP connection from %s I=[%s]:%d", hostname,
interface_address, interface_port);
-return string_sprintf("SMTP connection from %s", sender_fullhost);
+return string_sprintf("SMTP connection from %s", hostname);
+}
+
+
+
+#ifndef DISABLE_TLS
+/* Append TLS-related information to a log line
+
+Arguments:
+ g String under construction: allocated string to extend, or NULL
+
+Returns: Allocated string or NULL
+*/
+static gstring *
+s_tlslog(gstring * g)
+{
+if (LOGGING(tls_cipher) && tls_in.cipher)
+ {
+ g = string_append(g, 2, US" X=", tls_in.cipher);
+#ifdef EXPERIMENTAL_TLS_RESUME
+ if (LOGGING(tls_resumption) && tls_in.resumption & RESUME_USED)
+ g = string_catn(g, US"*", 1);
+#endif
+ }
+if (LOGGING(tls_certificate_verified) && tls_in.cipher)
+ g = string_append(g, 2, US" CV=", tls_in.certificate_verified? "yes":"no");
+if (LOGGING(tls_peerdn) && tls_in.peerdn)
+ g = string_append(g, 3, US" DN=\"", string_printing(tls_in.peerdn), US"\"");
+if (LOGGING(tls_sni) && tls_in.sni)
+ g = string_append(g, 3, US" SNI=\"", string_printing(tls_in.sni), US"\"");
+return g;
+}
+#endif
+
+/*************************************************
+* Log lack of MAIL if so configured *
+*************************************************/
+
+/* This function is called when an SMTP session ends. If the log selector
+smtp_no_mail is set, write a log line giving some details of what has happened
+in the SMTP session.
+
+Arguments: none
+Returns: nothing
+*/
+
+void
+smtp_log_no_mail(void)
+{
+uschar * sep, * s;
+gstring * g = NULL;
+
+if (smtp_mailcmd_count > 0 || !LOGGING(smtp_no_mail))
+ return;
+
+if (sender_host_authenticated)
+ {
+ g = string_append(g, 2, US" A=", sender_host_authenticated);
+ if (authenticated_id) g = string_append(g, 2, US":", authenticated_id);
+ }
+
+#ifndef DISABLE_TLS
+g = s_tlslog(g);
+#endif
+
+sep = smtp_connection_had[SMTP_HBUFF_SIZE-1] != SCH_NONE ? US" C=..." : US" C=";
+
+for (int i = smtp_ch_index; i < SMTP_HBUFF_SIZE; i++)
+ if (smtp_connection_had[i] != SCH_NONE)
+ {
+ g = string_append(g, 2, sep, smtp_names[smtp_connection_had[i]]);
+ sep = US",";
+ }
+
+for (int i = 0; i < smtp_ch_index; i++)
+ {
+ g = string_append(g, 2, sep, smtp_names[smtp_connection_had[i]]);
+ sep = US",";
+ }
+
+if (!(s = string_from_gstring(g))) s = US"";
+
+log_write(0, LOG_MAIN, "no MAIL in %sSMTP connection from %s D=%s%s",
+ f.tcp_in_fastopen ? f.tcp_in_fastopen_data ? US"TFO* " : US"TFO " : US"",
+ host_and_ident(FALSE), string_timesince(&smtp_connection_start), s);
+}
+
+
+/* Return list of recent smtp commands */
+
+uschar *
+smtp_cmd_hist(void)
+{
+gstring * list = NULL;
+uschar * s;
+
+for (int i = smtp_ch_index; i < SMTP_HBUFF_SIZE; i++)
+ if (smtp_connection_had[i] != SCH_NONE)
+ list = string_append_listele(list, ',', smtp_names[smtp_connection_had[i]]);
+
+for (int i = 0; i < smtp_ch_index; i++)
+ list = string_append_listele(list, ',', smtp_names[smtp_connection_had[i]]);
+
+s = string_from_gstring(list);
+return s ? s : US"";
}
+
/*************************************************
* Check HELO line and set sender_helo_name *
*************************************************/
/* Check the format of a HELO line. The data for HELO/EHLO is supposed to be
the domain name of the sending host, or an ip literal in square brackets. The
-arrgument is placed in sender_helo_name, which is in malloc store, because it
+argument is placed in sender_helo_name, which is in malloc store, because it
must persist over multiple incoming messages. If helo_accept_junk is set, this
host is permitted to send any old junk (needed for some broken hosts).
Otherwise, helo_allow_chars can be used for rogue characters in general
{
uschar *start = s;
uschar *end = s + Ustrlen(s);
-BOOL yield = helo_accept_junk;
+BOOL yield = fl.helo_accept_junk;
/* Discard any previous helo name */
-if (sender_helo_name != NULL)
- {
- store_free(sender_helo_name);
- sender_helo_name = NULL;
- }
+sender_helo_name = NULL;
/* Skip tests if junk is permitted. */
if (!yield)
- {
+
/* Allow the new standard form for IPv6 address literals, namely,
[IPv6:....], and because someone is bound to use it, allow an equivalent
IPv4 form. Allow plain addresses as well. */
/* Non-literals must be alpha, dot, hyphen, plus any non-valid chars
that have been configured (usually underscore - sigh). */
- else if (*s != 0)
- {
- yield = TRUE;
- while (*s != 0)
- {
+ else if (*s)
+ for (yield = TRUE; *s; s++)
if (!isalnum(*s) && *s != '.' && *s != '-' &&
Ustrchr(helo_allow_chars, *s) == NULL)
{
yield = FALSE;
break;
}
- s++;
- }
- }
- }
/* Save argument if OK */
-if (yield) sender_helo_name = string_copy_malloc(start);
+if (yield) sender_helo_name = string_copy_perm(start, TRUE);
return yield;
}
* Extract SMTP command option *
*************************************************/
-/* This function picks the next option setting off the end of smtp_command_argument. It
+/* This function picks the next option setting off the end of smtp_cmd_data. It
is called for MAIL FROM and RCPT TO commands, to pick off the optional ESMTP
things that can appear there.
extract_option(uschar **name, uschar **value)
{
uschar *n;
-uschar *v = smtp_command_argument + Ustrlen(smtp_command_argument) -1;
+uschar *v = smtp_cmd_data + Ustrlen(smtp_cmd_data) - 1;
while (isspace(*v)) v--;
v[1] = 0;
+while (v > smtp_cmd_data && *v != '=' && !isspace(*v))
+ {
+ /* Take care to not stop at a space embedded in a quoted local-part */
-while (v > smtp_command_argument && *v != '=' && !isspace(*v)) v--;
-if (*v != '=') return FALSE;
+ if (*v == '"') do v--; while (*v != '"' && v > smtp_cmd_data+1);
+ v--;
+ }
n = v;
-while(isalpha(n[-1])) n--;
-
-if (n[-1] != ' ') return FALSE;
-
-n[-1] = 0;
-*name = n;
+if (*v == '=')
+ {
+ while(isalpha(n[-1])) n--;
+ /* RFC says SP, but TAB seen in wild and other major MTAs accept it */
+ if (!isspace(n[-1])) return FALSE;
+ n[-1] = 0;
+ }
+else
+ {
+ n++;
+ if (v == smtp_cmd_data) return FALSE;
+ }
*v++ = 0;
+*name = n;
*value = v;
return TRUE;
}
-
-
/*************************************************
* Reset for new message *
*************************************************/
/* This function is called whenever the SMTP session is reset from
-within either of the setup functions.
+within either of the setup functions; also from the daemon loop.
Argument: the stacking pool storage reset point
Returns: nothing
*/
-static void
+void *
smtp_reset(void *reset_point)
{
-int i;
-store_reset(reset_point);
recipients_list = NULL;
rcpt_count = rcpt_defer_count = rcpt_fail_count =
raw_recipients_count = recipients_count = recipients_list_max = 0;
message_linecount = 0;
message_size = -1;
-acl_warn_headers = NULL;
-queue_only_policy = FALSE;
-deliver_freeze = FALSE; /* Can be set by ACL */
+acl_added_headers = NULL;
+acl_removed_headers = NULL;
+f.queue_only_policy = FALSE;
+rcpt_smtp_response = NULL;
+fl.rcpt_smtp_response_same = TRUE;
+fl.rcpt_in_progress = FALSE;
+f.deliver_freeze = FALSE; /* Can be set by ACL */
+freeze_tell = freeze_tell_config; /* Can be set by ACL */
fake_response = OK; /* Can be set by ACL */
#ifdef WITH_CONTENT_SCAN
-no_mbox_unspool = FALSE; /* Can be set by ACL */
+f.no_mbox_unspool = FALSE; /* Can be set by ACL */
#endif
-submission_mode = FALSE; /* Can be set by ACL */
-suppress_local_fixups = FALSE; /* Can be set by ACL */
-active_local_from_check = local_from_check; /* Can be set by ACL */
-active_local_sender_retain = local_sender_retain; /* Can be set by ACL */
-sender_address = NULL;
+f.submission_mode = FALSE; /* Can be set by ACL */
+f.suppress_local_fixups = f.suppress_local_fixups_default; /* Can be set by ACL */
+f.active_local_from_check = local_from_check; /* Can be set by ACL */
+f.active_local_sender_retain = local_sender_retain; /* Can be set by ACL */
+sending_ip_address = NULL;
+return_path = sender_address = NULL;
+sender_data = NULL; /* Can be set by ACL */
+deliver_localpart_parent = deliver_localpart_orig = NULL;
+deliver_domain_parent = deliver_domain_orig = NULL;
+callout_address = NULL;
submission_name = NULL; /* Can be set by ACL */
raw_sender = NULL; /* After SMTP rewrite, before qualifying */
sender_address_unrewritten = NULL; /* Set only after verify rewrite */
sender_verified_list = NULL; /* No senders verified */
memset(sender_address_cache, 0, sizeof(sender_address_cache));
memset(sender_domain_cache, 0, sizeof(sender_domain_cache));
+
authenticated_sender = NULL;
#ifdef EXPERIMENTAL_BRIGHTMAIL
bmi_run = 0;
bmi_verdicts = NULL;
#endif
-#ifdef EXPERIMENTAL_DOMAINKEYS
-dk_do_verify = 0;
+dnslist_domain = dnslist_matched = NULL;
+#ifdef SUPPORT_SPF
+spf_header_comment = spf_received = spf_result = spf_smtp_comment = NULL;
+spf_result_guessed = FALSE;
+#endif
+#ifndef DISABLE_DKIM
+dkim_cur_signer = dkim_signers =
+dkim_signing_domain = dkim_signing_selector = dkim_signatures = NULL;
+dkim_cur_signer = dkim_signers = dkim_signing_domain = dkim_signing_selector = NULL;
+f.dkim_disable_verify = FALSE;
+dkim_collect_input = 0;
+dkim_verify_overall = dkim_verify_status = dkim_verify_reason = NULL;
+dkim_key_length = 0;
+#endif
+#ifdef EXPERIMENTAL_DMARC
+f.dmarc_has_been_checked = f.dmarc_disable_verify = f.dmarc_enable_forensic = FALSE;
+dmarc_domain_policy = dmarc_status = dmarc_status_text =
+dmarc_used_domain = NULL;
+#endif
+#ifdef EXPERIMENTAL_ARC
+arc_state = arc_state_reason = NULL;
+#endif
+dsn_ret = 0;
+dsn_envid = NULL;
+deliver_host = deliver_host_address = NULL; /* Can be set by ACL */
+#ifndef DISABLE_PRDR
+prdr_requested = FALSE;
#endif
-#ifdef EXPERIMENTAL_SPF
-spf_header_comment = NULL;
-spf_received = NULL;
-spf_result = NULL;
-spf_smtp_comment = NULL;
+#ifdef SUPPORT_I18N
+message_smtputf8 = FALSE;
#endif
body_linecount = body_zerocount = 0;
ratelimiters_mail = NULL; /* Updated by ratelimit ACL condition */
/* Note that ratelimiters_conn persists across resets. */
-for (i = 0; i < ACL_M_MAX; i++) acl_var[ACL_C_MAX + i] = NULL;
+/* Reset message ACL variables */
+
+acl_var_m = NULL;
/* The message body variables use malloc store. They may be set if this is
not the first message in an SMTP session and the previous message caused them
to be referenced in an ACL. */
-if (message_body != NULL)
+if (message_body)
{
store_free(message_body);
message_body = NULL;
}
-if (message_body_end != NULL)
+if (message_body_end)
{
store_free(message_body_end);
message_body_end = NULL;
/* Warning log messages are also saved in malloc store. They are saved to avoid
repetition in the same message, but it seems right to repeat them for different
-messagess. */
+messages. */
-while (acl_warn_logged != NULL)
+while (acl_warn_logged)
{
string_item *this = acl_warn_logged;
acl_warn_logged = acl_warn_logged->next;
store_free(this);
}
+store_reset(reset_point);
+return store_mark();
}
smtp_setup_batch_msg(void)
{
int done = 0;
-void *reset_point = store_get(0);
+rmark reset_point = store_mark();
/* Save the line count at the start of each transaction - single commands
like HELO and RSET count as whole transactions. */
if ((receive_feof)()) return 0; /* Treat EOF as QUIT */
-smtp_reset(reset_point); /* Reset for start of message */
+cancel_cutthrough_connection(TRUE, US"smtp_setup_batch_msg");
+reset_point = smtp_reset(reset_point); /* Reset for start of message */
/* Deal with SMTP commands. This loop is exited by setting done to a POSITIVE
value. The values are 2 larger than the required yield of the function. */
uschar *recipient = NULL;
int start, end, sender_domain, recipient_domain;
- switch(smtp_read_command(FALSE))
+ switch(smtp_read_command(FALSE, GETC_BUFFER_UNLIMITED))
{
/* The HELO/EHLO commands set sender_address_helo if they have
valid data; otherwise they are ignored, except that they do
case HELO_CMD:
case EHLO_CMD:
- check_helo(smtp_command_argument);
- /* Fall through */
+ check_helo(smtp_cmd_data);
+ /* Fall through */
case RSET_CMD:
- smtp_reset(reset_point);
- bsmtp_transaction_linecount = receive_linecount;
- break;
+ cancel_cutthrough_connection(TRUE, US"RSET received");
+ reset_point = smtp_reset(reset_point);
+ bsmtp_transaction_linecount = receive_linecount;
+ break;
/* The MAIL FROM command requires an address as an operand. All we
it is the canonical extracted address which is all that is kept. */
case MAIL_CMD:
- if (sender_address != NULL)
- /* The function moan_smtp_batch() does not return. */
- moan_smtp_batch(cmd_buffer, "503 Sender already given");
+ smtp_mailcmd_count++; /* Count for no-mail log */
+ if (sender_address != NULL)
+ /* The function moan_smtp_batch() does not return. */
+ moan_smtp_batch(smtp_cmd_buffer, "503 Sender already given");
- if (smtp_command_argument[0] == 0)
- /* The function moan_smtp_batch() does not return. */
- moan_smtp_batch(cmd_buffer, "501 MAIL FROM must have an address operand");
+ if (smtp_cmd_data[0] == 0)
+ /* The function moan_smtp_batch() does not return. */
+ moan_smtp_batch(smtp_cmd_buffer, "501 MAIL FROM must have an address operand");
- /* Reset to start of message */
+ /* Reset to start of message */
- smtp_reset(reset_point);
+ cancel_cutthrough_connection(TRUE, US"MAIL received");
+ reset_point = smtp_reset(reset_point);
- /* Apply SMTP rewrite */
+ /* Apply SMTP rewrite */
- raw_sender = ((rewrite_existflags & rewrite_smtp) != 0)?
- rewrite_one(smtp_command_argument, rewrite_smtp|rewrite_smtp_sender, NULL, FALSE,
- US"", global_rewrite_rules) : smtp_command_argument;
+ raw_sender = ((rewrite_existflags & rewrite_smtp) != 0)?
+ rewrite_one(smtp_cmd_data, rewrite_smtp|rewrite_smtp_sender, NULL, FALSE,
+ US"", global_rewrite_rules) : smtp_cmd_data;
- /* Extract the address; the TRUE flag allows <> as valid */
+ /* Extract the address; the TRUE flag allows <> as valid */
- raw_sender =
- parse_extract_address(raw_sender, &errmess, &start, &end, &sender_domain,
- TRUE);
+ raw_sender =
+ parse_extract_address(raw_sender, &errmess, &start, &end, &sender_domain,
+ TRUE);
- if (raw_sender == NULL)
- /* The function moan_smtp_batch() does not return. */
- moan_smtp_batch(cmd_buffer, "501 %s", errmess);
+ if (!raw_sender)
+ /* The function moan_smtp_batch() does not return. */
+ moan_smtp_batch(smtp_cmd_buffer, "501 %s", errmess);
- sender_address = string_copy(raw_sender);
+ sender_address = string_copy(raw_sender);
- /* Qualify unqualified sender addresses if permitted to do so. */
+ /* Qualify unqualified sender addresses if permitted to do so. */
- if (sender_domain == 0 && sender_address[0] != 0 && sender_address[0] != '@')
- {
- if (allow_unqualified_sender)
- {
- sender_address = rewrite_address_qualify(sender_address, FALSE);
- DEBUG(D_receive) debug_printf("unqualified address %s accepted "
- "and rewritten\n", raw_sender);
- }
- /* The function moan_smtp_batch() does not return. */
- else moan_smtp_batch(cmd_buffer, "501 sender address must contain "
- "a domain");
- }
- break;
+ if ( !sender_domain
+ && sender_address[0] != 0 && sender_address[0] != '@')
+ if (f.allow_unqualified_sender)
+ {
+ sender_address = rewrite_address_qualify(sender_address, FALSE);
+ DEBUG(D_receive) debug_printf("unqualified address %s accepted "
+ "and rewritten\n", raw_sender);
+ }
+ /* The function moan_smtp_batch() does not return. */
+ else
+ moan_smtp_batch(smtp_cmd_buffer, "501 sender address must contain "
+ "a domain");
+ break;
/* The RCPT TO command requires an address as an operand. All we do
extracted address. */
case RCPT_CMD:
- if (sender_address == NULL)
- /* The function moan_smtp_batch() does not return. */
- moan_smtp_batch(cmd_buffer, "503 No sender yet given");
+ if (!sender_address)
+ /* The function moan_smtp_batch() does not return. */
+ moan_smtp_batch(smtp_cmd_buffer, "503 No sender yet given");
+
+ if (smtp_cmd_data[0] == 0)
+ /* The function moan_smtp_batch() does not return. */
+ moan_smtp_batch(smtp_cmd_buffer,
+ "501 RCPT TO must have an address operand");
+
+ /* Check maximum number allowed */
+
+ if (recipients_max > 0 && recipients_count + 1 > recipients_max)
+ /* The function moan_smtp_batch() does not return. */
+ moan_smtp_batch(smtp_cmd_buffer, "%s too many recipients",
+ recipients_max_reject? "552": "452");
+
+ /* Apply SMTP rewrite, then extract address. Don't allow "<>" as a
+ recipient address */
+
+ recipient = rewrite_existflags & rewrite_smtp
+ ? rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"",
+ global_rewrite_rules)
+ : smtp_cmd_data;
+
+ recipient = parse_extract_address(recipient, &errmess, &start, &end,
+ &recipient_domain, FALSE);
+
+ if (!recipient)
+ /* The function moan_smtp_batch() does not return. */
+ moan_smtp_batch(smtp_cmd_buffer, "501 %s", errmess);
+
+ /* If the recipient address is unqualified, qualify it if permitted. Then
+ add it to the list of recipients. */
+
+ if (!recipient_domain)
+ if (f.allow_unqualified_recipient)
+ {
+ DEBUG(D_receive) debug_printf("unqualified address %s accepted\n",
+ recipient);
+ recipient = rewrite_address_qualify(recipient, TRUE);
+ }
+ /* The function moan_smtp_batch() does not return. */
+ else
+ moan_smtp_batch(smtp_cmd_buffer,
+ "501 recipient address must contain a domain");
- if (smtp_command_argument[0] == 0)
- /* The function moan_smtp_batch() does not return. */
- moan_smtp_batch(cmd_buffer, "501 RCPT TO must have an address operand");
-
- /* Check maximum number allowed */
+ receive_add_recipient(recipient, -1);
+ break;
- if (recipients_max > 0 && recipients_count + 1 > recipients_max)
- /* The function moan_smtp_batch() does not return. */
- moan_smtp_batch(cmd_buffer, "%s too many recipients",
- recipients_max_reject? "552": "452");
- /* Apply SMTP rewrite, then extract address. Don't allow "<>" as a
- recipient address */
-
- recipient = ((rewrite_existflags & rewrite_smtp) != 0)?
- rewrite_one(smtp_command_argument, rewrite_smtp, NULL, FALSE, US"",
- global_rewrite_rules) : smtp_command_argument;
-
- /* rfc821_domains = TRUE; << no longer needed */
- recipient = parse_extract_address(recipient, &errmess, &start, &end,
- &recipient_domain, FALSE);
- /* rfc821_domains = FALSE; << no longer needed */
-
- if (recipient == NULL)
- /* The function moan_smtp_batch() does not return. */
- moan_smtp_batch(cmd_buffer, "501 %s", errmess);
-
- /* If the recipient address is unqualified, qualify it if permitted. Then
- add it to the list of recipients. */
-
- if (recipient_domain == 0)
- {
- if (allow_unqualified_recipient)
- {
- DEBUG(D_receive) debug_printf("unqualified address %s accepted\n",
- recipient);
- recipient = rewrite_address_qualify(recipient, TRUE);
- }
- /* The function moan_smtp_batch() does not return. */
- else moan_smtp_batch(cmd_buffer, "501 recipient address must contain "
- "a domain");
- }
- receive_add_recipient(recipient, -1);
- break;
-
-
- /* The DATA command is legal only if it follows successful MAIL FROM
- and RCPT TO commands. This function is complete when a valid DATA
- command is encountered. */
+ /* The DATA command is legal only if it follows successful MAIL FROM
+ and RCPT TO commands. This function is complete when a valid DATA
+ command is encountered. */
case DATA_CMD:
- if (sender_address == NULL || recipients_count <= 0)
- {
- /* The function moan_smtp_batch() does not return. */
- if (sender_address == NULL)
- moan_smtp_batch(cmd_buffer,
- "503 MAIL FROM:<sender> command must precede DATA");
+ if (!sender_address || recipients_count <= 0)
+ /* The function moan_smtp_batch() does not return. */
+ if (!sender_address)
+ moan_smtp_batch(smtp_cmd_buffer,
+ "503 MAIL FROM:<sender> command must precede DATA");
+ else
+ moan_smtp_batch(smtp_cmd_buffer,
+ "503 RCPT TO:<recipient> must precede DATA");
else
- moan_smtp_batch(cmd_buffer,
- "503 RCPT TO:<recipient> must precede DATA");
- }
- else
- {
- done = 3; /* DATA successfully achieved */
- message_ended = END_NOTENDED; /* Indicate in middle of message */
- }
- break;
+ {
+ done = 3; /* DATA successfully achieved */
+ message_ended = END_NOTENDED; /* Indicate in middle of message */
+ }
+ break;
/* The VRFY, EXPN, HELP, ETRN, and NOOP commands are ignored. */
case HELP_CMD:
case NOOP_CMD:
case ETRN_CMD:
- bsmtp_transaction_linecount = receive_linecount;
- break;
+ bsmtp_transaction_linecount = receive_linecount;
+ break;
case EOF_CMD:
case QUIT_CMD:
- done = 2;
- break;
+ done = 2;
+ break;
case BADARG_CMD:
- /* The function moan_smtp_batch() does not return. */
- moan_smtp_batch(cmd_buffer, "501 Unexpected argument data");
- break;
+ /* The function moan_smtp_batch() does not return. */
+ moan_smtp_batch(smtp_cmd_buffer, "501 Unexpected argument data");
+ break;
case BADCHAR_CMD:
- /* The function moan_smtp_batch() does not return. */
- moan_smtp_batch(cmd_buffer, "501 Unexpected NULL in SMTP command");
- break;
+ /* The function moan_smtp_batch() does not return. */
+ moan_smtp_batch(smtp_cmd_buffer, "501 Unexpected NULL in SMTP command");
+ break;
default:
- /* The function moan_smtp_batch() does not return. */
- moan_smtp_batch(cmd_buffer, "500 Command unrecognized");
- break;
+ /* The function moan_smtp_batch() does not return. */
+ moan_smtp_batch(smtp_cmd_buffer, "500 Command unrecognized");
+ break;
}
}
+#ifndef DISABLE_TLS
+static BOOL
+smtp_log_tls_fail(uschar * errstr)
+{
+uschar * conn_info = smtp_get_connection_info();
+
+if (Ustrncmp(conn_info, US"SMTP ", 5) == 0) conn_info += 5;
+/* I'd like to get separated H= here, but too hard for now */
+
+log_write(0, LOG_MAIN, "TLS error on %s %s", conn_info, errstr);
+return FALSE;
+}
+#endif
+
+
+
+
+#ifdef TCP_FASTOPEN
+static void
+tfo_in_check(void)
+{
+# ifdef TCP_INFO
+struct tcp_info tinfo;
+socklen_t len = sizeof(tinfo);
+
+if (getsockopt(fileno(smtp_out), IPPROTO_TCP, TCP_INFO, &tinfo, &len) == 0)
+#ifdef TCPI_OPT_SYN_DATA /* FreeBSD 11 does not seem to have this yet */
+ if (tinfo.tcpi_options & TCPI_OPT_SYN_DATA)
+ {
+ DEBUG(D_receive) debug_printf("TCP_FASTOPEN mode connection (ACKd data-on-SYN)\n");
+ f.tcp_in_fastopen_data = f.tcp_in_fastopen = TRUE;
+ }
+ else
+#endif
+ if (tinfo.tcpi_state == TCP_SYN_RECV)
+ {
+ DEBUG(D_receive) debug_printf("TCP_FASTOPEN mode connection (state TCP_SYN_RECV)\n");
+ f.tcp_in_fastopen = TRUE;
+ }
+# endif
+}
+#endif
+
+
/*************************************************
* Start an SMTP session *
*************************************************/
BOOL
smtp_start_session(void)
{
-int size = 256;
-int i, ptr;
-uschar *p, *s, *ss;
-
-/* If we are running in the test harness, and the incoming call is from
-127.0.0.2 (sic), have a short delay. This makes it possible to test handling of
-input sent too soon (before the banner is output). */
+int esclen;
+uschar *user_msg, *log_msg;
+uschar *code, *esc;
+uschar *p, *s;
+gstring * ss;
-if (running_in_test_harness &&
- sender_host_address != NULL &&
- Ustrcmp(sender_host_address, "127.0.0.2") == 0)
- sleep(1);
+gettimeofday(&smtp_connection_start, NULL);
+for (smtp_ch_index = 0; smtp_ch_index < SMTP_HBUFF_SIZE; smtp_ch_index++)
+ smtp_connection_had[smtp_ch_index] = SCH_NONE;
+smtp_ch_index = 0;
/* Default values for certain variables */
-helo_seen = esmtp = helo_accept_junk = FALSE;
+fl.helo_seen = fl.esmtp = fl.helo_accept_junk = FALSE;
+smtp_mailcmd_count = 0;
count_nonmail = TRUE_UNSET;
synprot_error_count = unknown_command_count = nonmail_command_count = 0;
smtp_delay_mail = smtp_rlm_base;
-auth_advertised = FALSE;
-pipelining_advertised = FALSE;
+fl.auth_advertised = FALSE;
+f.smtp_in_pipelining_advertised = f.smtp_in_pipelining_used = FALSE;
+f.pipelining_enable = TRUE;
sync_cmd_limit = NON_SYNC_CMD_NON_PIPELINING;
+fl.smtp_exit_function_called = FALSE; /* For avoiding loop in not-quit exit */
-memset(sender_host_cache, 0, sizeof(sender_host_cache));
+/* If receiving by -bs from a trusted user, or testing with -bh, we allow
+authentication settings from -oMaa to remain in force. */
-sender_host_authenticated = NULL;
+if (!host_checking && !f.sender_host_notsocket)
+ sender_host_auth_pubname = sender_host_authenticated = NULL;
authenticated_by = NULL;
-#ifdef SUPPORT_TLS
-tls_cipher = tls_peerdn = NULL;
-tls_advertised = FALSE;
+#ifndef DISABLE_TLS
+tls_in.cipher = tls_in.peerdn = NULL;
+tls_in.ourcert = tls_in.peercert = NULL;
+tls_in.sni = NULL;
+tls_in.ocsp = OCSP_NOT_REQ;
+fl.tls_advertised = FALSE;
+#endif
+fl.dsn_advertised = FALSE;
+#ifdef SUPPORT_I18N
+fl.smtputf8_advertised = FALSE;
#endif
/* Reset ACL connection variables */
-for (i = 0; i < ACL_C_MAX; i++) acl_var[i] = NULL;
+acl_var_c = NULL;
+
+/* Allow for trailing 0 in the command and data buffers. Tainted. */
-cmd_buffer = (uschar *)malloc(cmd_buffer_size + 1); /* allow for trailing 0 */
-if (cmd_buffer == NULL)
- log_write(0, LOG_MAIN|LOG_PANIC_DIE,
- "malloc() failed for SMTP command buffer");
+smtp_cmd_buffer = store_get_perm(2*SMTP_CMD_BUFFER_SIZE + 2, TRUE);
+
+smtp_cmd_buffer[0] = 0;
+smtp_data_buffer = smtp_cmd_buffer + SMTP_CMD_BUFFER_SIZE + 1;
/* For batched input, the protocol setting can be overridden from the
command line by a trusted caller. */
if (smtp_batched_input)
{
- if (received_protocol == NULL) received_protocol = US"local-bsmtp";
+ if (!received_protocol) received_protocol = US"local-bsmtp";
}
/* For non-batched SMTP input, the protocol setting is forced here. It will be
else
received_protocol =
- protocols[pnormal] + ((sender_host_address != NULL)? pnlocal : 0);
+ (sender_host_address ? protocols : protocols_local) [pnormal];
/* Set up the buffer for inputting using direct read() calls, and arrange to
-call the local functions instead of the standard C ones. */
+call the local functions instead of the standard C ones. Place a NUL at the
+end of the buffer to safety-stop C-string reads from it. */
-smtp_inbuffer = (uschar *)malloc(in_buffer_size);
-if (smtp_inbuffer == NULL)
+if (!(smtp_inbuffer = US malloc(IN_BUFFER_SIZE)))
log_write(0, LOG_MAIN|LOG_PANIC_DIE, "malloc() failed for SMTP input buffer");
+smtp_inbuffer[IN_BUFFER_SIZE-1] = '\0';
+
receive_getc = smtp_getc;
+receive_getbuf = smtp_getbuf;
+receive_get_cache = smtp_get_cache;
receive_ungetc = smtp_ungetc;
receive_feof = smtp_feof;
receive_ferror = smtp_ferror;
+receive_smtp_buffered = smtp_buffered;
smtp_inptr = smtp_inend = smtp_inbuffer;
smtp_had_eof = smtp_had_error = 0;
/* Set up the message size limit; this may be host-specific */
-thismessage_size_limit = expand_string_integer(message_size_limit);
-if (thismessage_size_limit < 0)
+thismessage_size_limit = expand_string_integer(message_size_limit, TRUE);
+if (expand_string_message)
{
if (thismessage_size_limit == -1)
log_write(0, LOG_MAIN|LOG_PANIC, "unable to expand message_size_limit: "
If smtp_accept_max and smtp_accept_reserve are set, keep some connections in
reserve for certain hosts and/or networks. */
-if (!sender_host_unknown)
+if (!f.sender_host_unknown)
{
int rc;
BOOL reserved_host = FALSE;
How to do this properly in IPv6 is not yet known. */
- #if !HAVE_IPV6 && !defined(NO_IP_OPTIONS)
+#if !HAVE_IPV6 && !defined(NO_IP_OPTIONS)
#ifdef GLIBC_IP_OPTIONS
#if (!defined __GLIBC__) || (__GLIBC__ < 2)
#define OPTSTYLE 3
#endif
- if (!host_checking && !sender_host_notsocket)
+ if (!host_checking && !f.sender_host_notsocket)
{
#if OPTSTYLE == 1
EXIM_SOCKLEN_T optlen = sizeof(struct ip_options) + MAX_IPOPTLEN;
- struct ip_options *ipopt = store_get(optlen);
+ struct ip_options *ipopt = store_get(optlen, FALSE);
#elif OPTSTYLE == 2
struct ip_opts ipoptblock;
struct ip_opts *ipopt = &ipoptblock;
DEBUG(D_receive) debug_printf("checking for IP options\n");
- if (getsockopt(fileno(smtp_out), IPPROTO_IP, IP_OPTIONS, (uschar *)(ipopt),
+ if (getsockopt(fileno(smtp_out), IPPROTO_IP, IP_OPTIONS, US (ipopt),
&optlen) < 0)
{
if (errno != ENOPROTOOPT)
{
log_write(0, LOG_MAIN, "getsockopt() failed from %s: %s",
host_and_ident(FALSE), strerror(errno));
- smtp_printf("451 SMTP service not available\r\n");
+ smtp_printf("451 SMTP service not available\r\n", FALSE);
return FALSE;
}
}
{
uschar *p = big_buffer;
uschar *pend = big_buffer + big_buffer_size;
- uschar *opt, *adptr;
+ uschar *adptr;
int optcount;
struct in_addr addr;
#if OPTSTYLE == 1
- uschar *optstart = (uschar *)(ipopt->__data);
+ uschar *optstart = US (ipopt->__data);
#elif OPTSTYLE == 2
- uschar *optstart = (uschar *)(ipopt->ip_opts);
+ uschar *optstart = US (ipopt->ip_opts);
#else
- uschar *optstart = (uschar *)(ipopt->ipopt_list);
+ uschar *optstart = US (ipopt->ipopt_list);
#endif
DEBUG(D_receive) debug_printf("IP options exist\n");
Ustrcpy(p, "IP options on incoming call:");
p += Ustrlen(p);
- for (opt = optstart; opt != NULL &&
- opt < (uschar *)(ipopt) + optlen;)
- {
+ for (uschar * opt = optstart; opt && opt < US (ipopt) + optlen; )
switch (*opt)
{
case IPOPT_EOL:
default:
{
- int i;
if (pend - p < 4 + 3*opt[1]) { opt = NULL; break; }
Ustrcat(p, "[ ");
p += 2;
- for (i = 0; i < opt[1]; i++)
- {
- sprintf(CS p, "%2.2x ", opt[i]);
- p += 3;
- }
+ for (int i = 0; i < opt[1]; i++)
+ p += sprintf(CS p, "%2.2x ", opt[i]);
*p++ = ']';
}
opt += opt[1];
break;
}
- }
*p = 0;
log_write(0, LOG_MAIN, "%s", big_buffer);
log_write(0, LOG_MAIN|LOG_REJECT,
"connection from %s refused (IP options)", host_and_ident(FALSE));
- smtp_printf("554 SMTP service not available\r\n");
+ smtp_printf("554 SMTP service not available\r\n", FALSE);
return FALSE;
}
else DEBUG(D_receive) debug_printf("no IP options found\n");
}
- #endif /* HAVE_IPV6 && !defined(NO_IP_OPTIONS) */
+#endif /* HAVE_IPV6 && !defined(NO_IP_OPTIONS) */
/* Set keep-alive in socket options. The option is on by default. This
setting is an attempt to get rid of some hanging connections that stick in
read() when the remote end (usually a dialup) goes away. */
- if (smtp_accept_keepalive && !sender_host_notsocket)
+ if (smtp_accept_keepalive && !f.sender_host_notsocket)
ip_keepalive(fileno(smtp_out), sender_host_address, FALSE);
/* If the current host matches host_lookup, set the name by doing a
set_process_info("handling incoming connection from %s",
host_and_ident(FALSE));
- /* Start up TLS if tls_on_connect is set. This is for supporting the legacy
- smtps port for use with older style SSL MTAs. */
+ /* Expand smtp_receive_timeout, if needed */
- #ifdef SUPPORT_TLS
- if (tls_on_connect && tls_server_start(tls_require_ciphers) != OK)
- return FALSE;
- #endif
+ if (smtp_receive_timeout_s)
+ {
+ uschar * exp;
+ if ( !(exp = expand_string(smtp_receive_timeout_s))
+ || !(*exp)
+ || (smtp_receive_timeout = readconf_readtime(exp, 0, FALSE)) < 0
+ )
+ log_write(0, LOG_MAIN|LOG_PANIC,
+ "bad value for smtp_receive_timeout: '%s'", exp ? exp : US"");
+ }
/* Test for explicit connection rejection */
{
log_write(L_connection_reject, LOG_MAIN|LOG_REJECT, "refused connection "
"from %s (host_reject_connection)", host_and_ident(FALSE));
- smtp_printf("554 SMTP service not available\r\n");
+ smtp_printf("554 SMTP service not available\r\n", FALSE);
return FALSE;
}
- /* Test with TCP Wrappers if so configured */
+ /* Test with TCP Wrappers if so configured. There is a problem in that
+ hosts_ctl() returns 0 (deny) under a number of system failure circumstances,
+ such as disks dying. In these cases, it is desirable to reject with a 4xx
+ error instead of a 5xx error. There isn't a "right" way to detect such
+ problems. The following kludge is used: errno is zeroed before calling
+ hosts_ctl(). If the result is "reject", a 5xx error is given only if the
+ value of errno is 0 or ENOENT (which happens if /etc/hosts.{allow,deny} does
+ not exist). */
- #ifdef USE_TCP_WRAPPERS
- if (!hosts_ctl("exim",
- (sender_host_name == NULL)? STRING_UNKNOWN : CS sender_host_name,
- (sender_host_address == NULL)? STRING_UNKNOWN : CS sender_host_address,
- (sender_ident == NULL)? STRING_UNKNOWN : CS sender_ident))
+#ifdef USE_TCP_WRAPPERS
+ errno = 0;
+ if (!(tcp_wrappers_name = expand_string(tcp_wrappers_daemon_name)))
+ log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" "
+ "(tcp_wrappers_name) failed: %s", string_printing(tcp_wrappers_name),
+ expand_string_message);
+
+ if (!hosts_ctl(tcp_wrappers_name,
+ sender_host_name ? CS sender_host_name : STRING_UNKNOWN,
+ sender_host_address ? CS sender_host_address : STRING_UNKNOWN,
+ sender_ident ? CS sender_ident : STRING_UNKNOWN))
{
- HDEBUG(D_receive) debug_printf("tcp wrappers rejection\n");
- log_write(L_connection_reject,
- LOG_MAIN|LOG_REJECT, "refused connection from %s "
- "(tcp wrappers)", host_and_ident(FALSE));
- smtp_printf("554 SMTP service not available\r\n");
+ if (errno == 0 || errno == ENOENT)
+ {
+ HDEBUG(D_receive) debug_printf("tcp wrappers rejection\n");
+ log_write(L_connection_reject,
+ LOG_MAIN|LOG_REJECT, "refused connection from %s "
+ "(tcp wrappers)", host_and_ident(FALSE));
+ smtp_printf("554 SMTP service not available\r\n", FALSE);
+ }
+ else
+ {
+ int save_errno = errno;
+ HDEBUG(D_receive) debug_printf("tcp wrappers rejected with unexpected "
+ "errno value %d\n", save_errno);
+ log_write(L_connection_reject,
+ LOG_MAIN|LOG_REJECT, "temporarily refused connection from %s "
+ "(tcp wrappers errno=%d)", host_and_ident(FALSE), save_errno);
+ smtp_printf("451 Temporary local problem - please try later\r\n", FALSE);
+ }
return FALSE;
}
- #endif
+#endif
- /* Check for reserved slots. Note that the count value doesn't include
- this process, as it gets upped in the parent process. */
+ /* Check for reserved slots. The value of smtp_accept_count has already been
+ incremented to include this process. */
if (smtp_accept_max > 0 &&
- smtp_accept_count + 1 > smtp_accept_max - smtp_accept_reserve)
+ smtp_accept_count > smtp_accept_max - smtp_accept_reserve)
{
if ((rc = verify_check_host(&smtp_reserve_hosts)) != OK)
{
log_write(L_connection_reject,
LOG_MAIN, "temporarily refused connection from %s: not in "
"reserve list: connected=%d max=%d reserve=%d%s",
- host_and_ident(FALSE), smtp_accept_count, smtp_accept_max,
+ host_and_ident(FALSE), smtp_accept_count - 1, smtp_accept_max,
smtp_accept_reserve, (rc == DEFER)? " (lookup deferred)" : "");
smtp_printf("421 %s: Too many concurrent SMTP connections; "
- "please try again later\r\n", smtp_active_hostname);
+ "please try again later\r\n", FALSE, smtp_active_hostname);
return FALSE;
}
reserved_host = TRUE;
LOG_MAIN, "temporarily refused connection from %s: not in "
"reserve list and load average = %.2f", host_and_ident(FALSE),
(double)load_average/1000.0);
- smtp_printf("421 %s: Too much load; please try again later\r\n",
+ smtp_printf("421 %s: Too much load; please try again later\r\n", FALSE,
smtp_active_hostname);
return FALSE;
}
addresses in the headers. For a site that permits no qualification, this
won't take long, however. */
- allow_unqualified_sender =
+ f.allow_unqualified_sender =
verify_check_host(&sender_unqualified_hosts) == OK;
- allow_unqualified_recipient =
+ f.allow_unqualified_recipient =
verify_check_host(&recipient_unqualified_hosts) == OK;
/* Determine whether HELO/EHLO is required for this host. The requirement
can be hard or soft. */
- helo_required = verify_check_host(&helo_verify_hosts) == OK;
- if (!helo_required)
- helo_verify = verify_check_host(&helo_try_verify_hosts) == OK;
+ fl.helo_required = verify_check_host(&helo_verify_hosts) == OK;
+ if (!fl.helo_required)
+ fl.helo_verify = verify_check_host(&helo_try_verify_hosts) == OK;
/* Determine whether this hosts is permitted to send syntactic junk
after a HELO or EHLO command. */
- helo_accept_junk = verify_check_host(&helo_accept_junk_hosts) == OK;
+ fl.helo_accept_junk = verify_check_host(&helo_accept_junk_hosts) == OK;
}
/* For batch SMTP input we are now done. */
if (smtp_batched_input) return TRUE;
-/* Run the ACL if it exists */
+/* If valid Proxy Protocol source is connecting, set up session.
+ * Failure will not allow any SMTP function other than QUIT. */
+
+#ifdef SUPPORT_PROXY
+proxy_session = FALSE;
+f.proxy_session_failed = FALSE;
+if (check_proxy_protocol_host())
+ setup_proxy_protocol_host();
+#endif
+
+ /* Start up TLS if tls_on_connect is set. This is for supporting the legacy
+ smtps port for use with older style SSL MTAs. */
+
+#ifndef DISABLE_TLS
+ if (tls_in.on_connect)
+ {
+ if (tls_server_start(tls_require_ciphers, &user_msg) != OK)
+ return smtp_log_tls_fail(user_msg);
+ cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd = TRUE;
+ }
+#endif
+
+/* Run the connect ACL if it exists */
-if (acl_smtp_connect != NULL)
+user_msg = NULL;
+if (acl_smtp_connect)
{
int rc;
- uschar *user_msg, *log_msg;
- rc = acl_check(ACL_WHERE_CONNECT, NULL, acl_smtp_connect, &user_msg,
- &log_msg);
- if (rc != OK)
+ if ((rc = acl_check(ACL_WHERE_CONNECT, NULL, acl_smtp_connect, &user_msg,
+ &log_msg)) != OK)
{
- (void)smtp_handle_acl_fail(ACL_WHERE_CONNECT, rc, user_msg, log_msg);
+ (void) smtp_handle_acl_fail(ACL_WHERE_CONNECT, rc, user_msg, log_msg);
return FALSE;
}
}
/* Output the initial message for a two-way SMTP connection. It may contain
newlines, which then cause a multi-line response to be given. */
-s = expand_string(smtp_banner);
-if (s == NULL)
- log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" (smtp_banner) "
- "failed: %s", smtp_banner, expand_string_message);
+code = US"220"; /* Default status code */
+esc = US""; /* Default extended status code */
+esclen = 0; /* Length of esc */
+
+if (!user_msg)
+ {
+ if (!(s = expand_string(smtp_banner)))
+ log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" (smtp_banner) "
+ "failed: %s", smtp_banner, expand_string_message);
+ }
+else
+ {
+ int codelen = 3;
+ s = user_msg;
+ smtp_message_code(&code, &codelen, &s, NULL, TRUE);
+ if (codelen > 4)
+ {
+ esc = code + 4;
+ esclen = codelen - 4;
+ }
+ }
/* Remove any terminating newlines; might as well remove trailing space too */
first, and output it in one fell swoop. This gives a better chance of it
ending up as a single packet. */
-ss = store_get(size);
-ptr = 0;
+ss = string_get(256);
p = s;
do /* At least once, in case we have an empty string */
{
int len;
uschar *linebreak = Ustrchr(p, '\n');
- if (linebreak == NULL)
+ ss = string_catn(ss, code, 3);
+ if (!linebreak)
{
len = Ustrlen(p);
- ss = string_cat(ss, &size, &ptr, US"220 ", 4);
+ ss = string_catn(ss, US" ", 1);
}
else
{
len = linebreak - p;
- ss = string_cat(ss, &size, &ptr, US"220-", 4);
+ ss = string_catn(ss, US"-", 1);
}
- ss = string_cat(ss, &size, &ptr, p, len);
- ss = string_cat(ss, &size, &ptr, US"\r\n", 2);
+ ss = string_catn(ss, esc, esclen);
+ ss = string_catn(ss, p, len);
+ ss = string_catn(ss, US"\r\n", 2);
p += len;
- if (linebreak != NULL) p++;
+ if (linebreak) p++;
}
-while (*p != 0);
-
-ss[ptr] = 0; /* string_cat leaves room for this */
+while (*p);
/* Before we write the banner, check that there is no input pending, unless
this synchronisation check is disabled. */
-if (smtp_enforce_sync && sender_host_address != NULL && !sender_host_notsocket)
- {
- fd_set fds;
- struct timeval tzero;
- tzero.tv_sec = 0;
- tzero.tv_usec = 0;
- FD_ZERO(&fds);
- FD_SET(fileno(smtp_in), &fds);
- if (select(fileno(smtp_in) + 1, (SELECT_ARG2_TYPE *)&fds, NULL, NULL,
- &tzero) > 0)
+#ifdef SUPPORT_PIPE_CONNECT
+fl.pipe_connect_acceptable =
+ sender_host_address && verify_check_host(&pipe_connect_advertise_hosts) == OK;
+
+if (!check_sync())
+ if (fl.pipe_connect_acceptable)
+ f.smtp_in_early_pipe_used = TRUE;
+ else
+#else
+if (!check_sync())
+#endif
{
- int rc = read(fileno(smtp_in), smtp_inbuffer, in_buffer_size);
- if (rc > 0)
- {
- if (rc > 150) rc = 150;
- smtp_inbuffer[rc] = 0;
- log_write(0, LOG_MAIN|LOG_REJECT, "SMTP protocol "
- "synchronization error (input sent without waiting for greeting): "
- "rejected connection from %s input=\"%s\"", host_and_ident(TRUE),
- string_printing(smtp_inbuffer));
- smtp_printf("554 SMTP synchronization error\r\n");
- return FALSE;
- }
+ unsigned n = smtp_inend - smtp_inptr;
+ if (n > 32) n = 32;
+
+ log_write(0, LOG_MAIN|LOG_REJECT, "SMTP protocol "
+ "synchronization error (input sent without waiting for greeting): "
+ "rejected connection from %s input=\"%s\"", host_and_ident(TRUE),
+ string_printing(string_copyn(smtp_inptr, n)));
+ smtp_printf("554 SMTP synchronization error\r\n", FALSE);
+ return FALSE;
}
- }
/* Now output the banner */
+/*XXX the ehlo-resp code does its own tls/nontls bit. Maybe subroutine that? */
+
+smtp_printf("%s",
+#ifdef SUPPORT_PIPE_CONNECT
+ fl.pipe_connect_acceptable && pipeline_connect_sends(),
+#else
+ FALSE,
+#endif
+ string_from_gstring(ss));
+
+/* Attempt to see if we sent the banner before the last ACK of the 3-way
+handshake arrived. If so we must have managed a TFO. */
+
+#ifdef TCP_FASTOPEN
+tfo_in_check();
+#endif
-smtp_printf("%s", ss);
return TRUE;
}
log_write(type, LOG_MAIN, "SMTP %s error in \"%s\" %s %s",
(type == L_smtp_syntax_error)? "syntax" : "protocol",
- string_printing(cmd_buffer), host_and_ident(TRUE), errmess);
+ string_printing(smtp_cmd_buffer), host_and_ident(TRUE), errmess);
if (++synprot_error_count > smtp_max_synprot_errors)
{
yield = 1;
log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many "
"syntax or protocol errors (last command was \"%s\")",
- host_and_ident(FALSE), cmd_buffer);
+ host_and_ident(FALSE), string_printing(smtp_cmd_buffer));
}
if (code > 0)
{
- smtp_printf("%d%c%s%s%s\r\n", code, (yield == 1)? '-' : ' ',
- (data == NULL)? US"" : data, (data == NULL)? US"" : US": ", errmess);
+ smtp_printf("%d%c%s%s%s\r\n", FALSE, code, yield == 1 ? '-' : ' ',
+ data ? data : US"", data ? US": " : US"", errmess);
if (yield == 1)
- smtp_printf("%d Too many syntax or protocol errors\r\n", code);
+ smtp_printf("%d Too many syntax or protocol errors\r\n", FALSE, code);
}
return yield;
-/*************************************************
-* Log incomplete transactions *
-*************************************************/
-
-/* This function is called after a transaction has been aborted by RSET, QUIT,
-connection drops or other errors. It logs the envelope information received
-so far in order to preserve address verification attempts.
-
-Argument: string to indicate what aborted the transaction
-Returns: nothing
-*/
-
-static void
-incomplete_transaction_log(uschar *what)
-{
-if (sender_address == NULL || /* No transaction in progress */
- (log_write_selector & L_smtp_incomplete_transaction) == 0 /* Not logging */
- ) return;
-
-/* Build list of recipients for logging */
-
-if (recipients_count > 0)
- {
- int i;
- raw_recipients = store_get(recipients_count * sizeof(uschar *));
- for (i = 0; i < recipients_count; i++)
- raw_recipients[i] = recipients_list[i].address;
- raw_recipients_count = recipients_count;
- }
-
-log_write(L_smtp_incomplete_transaction, LOG_MAIN|LOG_SENDER|LOG_RECIPIENTS,
- "%s incomplete transaction (%s)", host_and_ident(TRUE), what);
-}
-
-
-
-
/*************************************************
* Send SMTP response, possibly multiline *
*************************************************/
output nothing for non-final calls, and only the first line for anything else.
Arguments:
- code SMTP code
+ code SMTP code, may involve extended status codes
+ codelen length of smtp code; if > 4 there's an ESC
final FALSE if the last line isn't the final line
msg message text, possibly containing newlines
*/
void
-smtp_respond(int code, BOOL final, uschar *msg)
+smtp_respond(uschar* code, int codelen, BOOL final, uschar *msg)
{
-if (!final && no_multiline_responses) return;
+int esclen = 0;
+uschar *esc = US"";
+
+if (!final && f.no_multiline_responses) return;
+
+if (codelen > 4)
+ {
+ esc = code + 4;
+ esclen = codelen - 4;
+ }
+
+/* If this is the first output for a (non-batch) RCPT command, see if all RCPTs
+have had the same. Note: this code is also present in smtp_printf(). It would
+be tidier to have it only in one place, but when it was added, it was easier to
+do it that way, so as not to have to mess with the code for the RCPT command,
+which sometimes uses smtp_printf() and sometimes smtp_respond(). */
+
+if (fl.rcpt_in_progress)
+ {
+ if (rcpt_smtp_response == NULL)
+ rcpt_smtp_response = string_copy(msg);
+ else if (fl.rcpt_smtp_response_same &&
+ Ustrcmp(rcpt_smtp_response, msg) != 0)
+ fl.rcpt_smtp_response_same = FALSE;
+ fl.rcpt_in_progress = FALSE;
+ }
+
+/* Now output the message, splitting it up into multiple lines if necessary.
+We only handle pipelining these responses as far as nonfinal/final groups,
+not the whole MAIL/RCPT/DATA response set. */
for (;;)
{
uschar *nl = Ustrchr(msg, '\n');
if (nl == NULL)
{
- smtp_printf("%d%c%s\r\n", code, final? ' ':'-', msg);
+ smtp_printf("%.3s%c%.*s%s\r\n", !final, code, final ? ' ':'-', esclen, esc, msg);
return;
}
- else if (nl[1] == 0 || no_multiline_responses)
+ else if (nl[1] == 0 || f.no_multiline_responses)
{
- smtp_printf("%d%c%.*s\r\n", code, final? ' ':'-', (int)(nl - msg), msg);
+ smtp_printf("%.3s%c%.*s%.*s\r\n", !final, code, final ? ' ':'-', esclen, esc,
+ (int)(nl - msg), msg);
return;
}
else
{
- smtp_printf("%d-%.*s\r\n", code, (int)(nl - msg), msg);
+ smtp_printf("%.3s-%.*s%.*s\r\n", TRUE, code, esclen, esc, (int)(nl - msg), msg);
msg = nl + 1;
while (isspace(*msg)) msg++;
}
+/*************************************************
+* Parse user SMTP message *
+*************************************************/
+
+/* This function allows for user messages overriding the response code details
+by providing a suitable response code string at the start of the message
+user_msg. Check the message for starting with a response code and optionally an
+extended status code. If found, check that the first digit is valid, and if so,
+change the code pointer and length to use the replacement. An invalid code
+causes a panic log; in this case, if the log messages is the same as the user
+message, we must also adjust the value of the log message to show the code that
+is actually going to be used (the original one).
+
+This function is global because it is called from receive.c as well as within
+this module.
+
+Note that the code length returned includes the terminating whitespace
+character, which is always included in the regex match.
+
+Arguments:
+ code SMTP code, may involve extended status codes
+ codelen length of smtp code; if > 4 there's an ESC
+ msg message text
+ log_msg optional log message, to be adjusted with the new SMTP code
+ check_valid if true, verify the response code
+
+Returns: nothing
+*/
+
+void
+smtp_message_code(uschar **code, int *codelen, uschar **msg, uschar **log_msg,
+ BOOL check_valid)
+{
+int n;
+int ovector[3];
+
+if (!msg || !*msg) return;
+
+if ((n = pcre_exec(regex_smtp_code, NULL, CS *msg, Ustrlen(*msg), 0,
+ PCRE_EOPT, ovector, sizeof(ovector)/sizeof(int))) < 0) return;
+
+if (check_valid && (*msg)[0] != (*code)[0])
+ {
+ log_write(0, LOG_MAIN|LOG_PANIC, "configured error code starts with "
+ "incorrect digit (expected %c) in \"%s\"", (*code)[0], *msg);
+ if (log_msg != NULL && *log_msg == *msg)
+ *log_msg = string_sprintf("%s %s", *code, *log_msg + ovector[1]);
+ }
+else
+ {
+ *code = *msg;
+ *codelen = ovector[1]; /* Includes final space */
+ }
+*msg += ovector[1]; /* Chop the code off the message */
+return;
+}
+
+
+
+
/*************************************************
* Handle an ACL failure *
*************************************************/
/* This function is called when acl_check() fails. As well as calls from within
this module, it is called from receive.c for an ACL after DATA. It sorts out
-logging the incident, and sets up the error response. A message containing
+logging the incident, and sends the error response. A message containing
newlines is turned into a multiline SMTP response, but for logging, only the
first line is used.
-There's a table of the response codes to use in globals.c, along with the table
-of names. VFRY is special. Despite RFC1123 it defaults disabled in Exim.
-However, discussion in connection with RFC 821bis (aka RFC 2821) has concluded
-that the response should be 252 in the disabled state, because there are broken
-clients that try VRFY before RCPT. A 5xx response should be given only when the
-address is positively known to be undeliverable. Sigh. Also, for ETRN, 458 is
-given on refusal, and for AUTH, 503.
+There's a table of default permanent failure response codes to use in
+globals.c, along with the table of names. VFRY is special. Despite RFC1123 it
+defaults disabled in Exim. However, discussion in connection with RFC 821bis
+(aka RFC 2821) has concluded that the response should be 252 in the disabled
+state, because there are broken clients that try VRFY before RCPT. A 5xx
+response should be given only when the address is positively known to be
+undeliverable. Sigh. We return 252 if there is no VRFY ACL or it provides
+no explicit code, but if there is one we let it know best.
+Also, for ETRN, 458 is given on refusal, and for AUTH, 503.
+
+From Exim 4.63, it is possible to override the response code details by
+providing a suitable response code string at the start of the message provided
+in user_msg. The code's first digit is checked for validity.
Arguments:
- where where the ACL was called from
- rc the failure code
- user_msg a message that can be included in an SMTP response
- log_msg a message for logging
+ where where the ACL was called from
+ rc the failure code
+ user_msg a message that can be included in an SMTP response
+ log_msg a message for logging
Returns: 0 in most cases
2 if the failure code was FAIL_DROP, in which case the
int
smtp_handle_acl_fail(int where, int rc, uschar *user_msg, uschar *log_msg)
{
-int code = acl_wherecodes[where];
BOOL drop = rc == FAIL_DROP;
+int codelen = 3;
+uschar *smtp_code;
uschar *lognl;
uschar *sender_info = US"";
uschar *what =
#ifdef WITH_CONTENT_SCAN
- (where == ACL_WHERE_MIME)? US"during MIME ACL checks" :
+ where == ACL_WHERE_MIME ? US"during MIME ACL checks" :
+#endif
+ where == ACL_WHERE_PREDATA ? US"DATA" :
+ where == ACL_WHERE_DATA ? US"after DATA" :
+#ifndef DISABLE_PRDR
+ where == ACL_WHERE_PRDR ? US"after DATA PRDR" :
#endif
- (where == ACL_WHERE_PREDATA)? US"DATA" :
- (where == ACL_WHERE_DATA)? US"after DATA" :
- (smtp_command_argument == NULL)?
- string_sprintf("%s in \"connect\" ACL", acl_wherenames[where]) :
- string_sprintf("%s %s", acl_wherenames[where], smtp_command_argument);
+ smtp_cmd_data ?
+ string_sprintf("%s %s", acl_wherenames[where], smtp_cmd_data) :
+ string_sprintf("%s in \"connect\" ACL", acl_wherenames[where]);
if (drop) rc = FAIL;
+/* Set the default SMTP code, and allow a user message to change it. */
+
+smtp_code = rc == FAIL ? acl_wherecodes[where] : US"451";
+smtp_message_code(&smtp_code, &codelen, &user_msg, &log_msg,
+ where != ACL_WHERE_VRFY);
+
/* We used to have sender_address here; however, there was a bug that was not
updating sender_address after a rewrite during a verify. When this bug was
fixed, sender_address at this point became the rewritten address. I'm not sure
if (where == ACL_WHERE_RCPT || where == ACL_WHERE_DATA || where == ACL_WHERE_MIME)
#endif
{
- sender_info = string_sprintf("F=<%s> ", (sender_address_unrewritten != NULL)?
- sender_address_unrewritten : sender_address);
+ sender_info = string_sprintf("F=<%s>%s%s%s%s ",
+ sender_address_unrewritten ? sender_address_unrewritten : sender_address,
+ sender_host_authenticated ? US" A=" : US"",
+ sender_host_authenticated ? sender_host_authenticated : US"",
+ sender_host_authenticated && authenticated_id ? US":" : US"",
+ sender_host_authenticated && authenticated_id ? authenticated_id : US""
+ );
}
/* If there's been a sender verification failure with a specific message, and
we have not sent a response about it yet, do so now, as a preliminary line for
-failures, but not defers. However, log it in both cases. */
+failures, but not defers. However, always log it for defer, and log it for fail
+unless the sender_verify_fail log selector has been turned off. */
-if (sender_verified_failed != NULL &&
+if (sender_verified_failed &&
!testflag(sender_verified_failed, af_sverify_told))
{
+ BOOL save_rcpt_in_progress = fl.rcpt_in_progress;
+ fl.rcpt_in_progress = FALSE; /* So as not to treat these as the error */
+
setflag(sender_verified_failed, af_sverify_told);
- log_write(0, LOG_MAIN|LOG_REJECT, "%s sender verify %s for <%s>%s",
- host_and_ident(TRUE),
- ((sender_verified_failed->special_action & 255) == DEFER)? "defer" : "fail",
- sender_verified_failed->address,
- (sender_verified_failed->message == NULL)? US"" :
- string_sprintf(": %s", sender_verified_failed->message));
+ if (rc != FAIL || LOGGING(sender_verify_fail))
+ log_write(0, LOG_MAIN|LOG_REJECT, "%s sender verify %s for <%s>%s",
+ host_and_ident(TRUE),
+ ((sender_verified_failed->special_action & 255) == DEFER)? "defer":"fail",
+ sender_verified_failed->address,
+ (sender_verified_failed->message == NULL)? US"" :
+ string_sprintf(": %s", sender_verified_failed->message));
- if (rc == FAIL && sender_verified_failed->user_message != NULL)
- smtp_respond(code, FALSE, string_sprintf(
+ if (rc == FAIL && sender_verified_failed->user_message)
+ smtp_respond(smtp_code, codelen, FALSE, string_sprintf(
testflag(sender_verified_failed, af_verify_pmfail)?
"Postmaster verification failed while checking <%s>\n%s\n"
"Several RFCs state that you are required to have a postmaster\n"
"Verification failed for <%s>\n%s",
sender_verified_failed->address,
sender_verified_failed->user_message));
+
+ fl.rcpt_in_progress = save_rcpt_in_progress;
}
/* Sort out text for logging */
-log_msg = (log_msg == NULL)? US"" : string_sprintf(": %s", log_msg);
-lognl = Ustrchr(log_msg, '\n');
-if (lognl != NULL) *lognl = 0;
+log_msg = log_msg ? string_sprintf(": %s", log_msg) : US"";
+if ((lognl = Ustrchr(log_msg, '\n'))) *lognl = 0;
/* Send permanent failure response to the command, but the code used isn't
always a 5xx one - see comments at the start of this function. If the original
rc was FAIL_DROP we drop the connection and yield 2. */
-if (rc == FAIL) smtp_respond(code, TRUE, (user_msg == NULL)?
- US"Administrative prohibition" : user_msg);
+if (rc == FAIL)
+ smtp_respond(smtp_code, codelen, TRUE,
+ user_msg ? user_msg : US"Administrative prohibition");
/* Send temporary failure response to the command. Don't give any details,
unless acl_temp_details is set. This is TRUE for a callout defer, a "defer"
be re-implemented in a tidier fashion. */
else
- {
- if (acl_temp_details && user_msg != NULL)
+ if (f.acl_temp_details && user_msg)
{
- if (smtp_return_error_details &&
- sender_verified_failed != NULL &&
- sender_verified_failed->message != NULL)
- {
- smtp_respond(451, FALSE, sender_verified_failed->message);
- }
- smtp_respond(451, TRUE, user_msg);
+ if ( smtp_return_error_details
+ && sender_verified_failed
+ && sender_verified_failed->message
+ )
+ smtp_respond(smtp_code, codelen, FALSE, sender_verified_failed->message);
+
+ smtp_respond(smtp_code, codelen, TRUE, user_msg);
}
else
- smtp_printf("451 Temporary local problem - please try later\r\n");
- }
+ smtp_respond(smtp_code, codelen, TRUE,
+ US"Temporary local problem - please try later");
-/* Log the incident. If the connection is not forcibly to be dropped, return 0.
-Otherwise, log why it is closing if required and return 2. */
+/* Log the incident to the logs that are specified by log_reject_target
+(default main, reject). This can be empty to suppress logging of rejections. If
+the connection is not forcibly to be dropped, return 0. Otherwise, log why it
+is closing if required and return 2. */
-log_write(0, LOG_MAIN|LOG_REJECT, "%s %s%srejected %s%s",
- host_and_ident(TRUE),
- sender_info, (rc == FAIL)? US"" : US"temporarily ", what, log_msg);
+if (log_reject_target != 0)
+ {
+#ifndef DISABLE_TLS
+ gstring * g = s_tlslog(NULL);
+ uschar * tls = string_from_gstring(g);
+ if (!tls) tls = US"";
+#else
+ uschar * tls = US"";
+#endif
+ log_write(where == ACL_WHERE_CONNECT ? L_connection_reject : 0,
+ log_reject_target, "%s%s%s %s%srejected %s%s",
+ LOGGING(dnssec) && sender_host_dnssec ? US" DS" : US"",
+ host_and_ident(TRUE),
+ tls,
+ sender_info,
+ rc == FAIL ? US"" : US"temporarily ",
+ what, log_msg);
+ }
if (!drop) return 0;
log_write(L_smtp_connection, LOG_MAIN, "%s closed by DROP in ACL",
smtp_get_connection_info());
+
+/* Run the not-quit ACL, but without any custom messages. This should not be a
+problem, because we get here only if some other ACL has issued "drop", and
+in that case, *its* custom messages will have been used above. */
+
+smtp_notquit_exit(US"acl-drop", NULL, NULL);
return 2;
}
+/*************************************************
+* Handle SMTP exit when QUIT is not given *
+*************************************************/
+
+/* This function provides a logging/statistics hook for when an SMTP connection
+is dropped on the floor or the other end goes away. It's a global function
+because it's called from receive.c as well as this module. As well as running
+the NOTQUIT ACL, if there is one, this function also outputs a final SMTP
+response, either with a custom message from the ACL, or using a default. There
+is one case, however, when no message is output - after "drop". In that case,
+the ACL that obeyed "drop" has already supplied the custom message, and NULL is
+passed to this function.
+
+In case things go wrong while processing this function, causing an error that
+may re-enter this function, there is a recursion check.
+
+Arguments:
+ reason What $smtp_notquit_reason will be set to in the ACL;
+ if NULL, the ACL is not run
+ code The error code to return as part of the response
+ defaultrespond The default message if there's no user_msg
+
+Returns: Nothing
+*/
+
+void
+smtp_notquit_exit(uschar *reason, uschar *code, uschar *defaultrespond, ...)
+{
+int rc;
+uschar *user_msg = NULL;
+uschar *log_msg = NULL;
+
+/* Check for recursive call */
+
+if (fl.smtp_exit_function_called)
+ {
+ log_write(0, LOG_PANIC, "smtp_notquit_exit() called more than once (%s)",
+ reason);
+ return;
+ }
+fl.smtp_exit_function_called = TRUE;
+
+/* Call the not-QUIT ACL, if there is one, unless no reason is given. */
+
+if (acl_smtp_notquit && reason)
+ {
+ smtp_notquit_reason = reason;
+ if ((rc = acl_check(ACL_WHERE_NOTQUIT, NULL, acl_smtp_notquit, &user_msg,
+ &log_msg)) == ERROR)
+ log_write(0, LOG_MAIN|LOG_PANIC, "ACL for not-QUIT returned ERROR: %s",
+ log_msg);
+ }
+
+/* If the connection was dropped, we certainly are no longer talking TLS */
+tls_in.active.sock = -1;
+
+/* Write an SMTP response if we are expected to give one. As the default
+responses are all internal, they should be reasonable size. */
+
+if (code && defaultrespond)
+ {
+ if (user_msg)
+ smtp_respond(code, 3, TRUE, user_msg);
+ else
+ {
+ gstring * g;
+ va_list ap;
+
+ va_start(ap, defaultrespond);
+ g = string_vformat(NULL, SVFMT_EXTEND|SVFMT_REBUFFER, CS defaultrespond, ap);
+ va_end(ap);
+ smtp_printf("%s %s\r\n", FALSE, code, string_from_gstring(g));
+ }
+ mac_smtp_fflush();
+ }
+}
+
+
+
+
/*************************************************
* Verify HELO argument *
*************************************************/
HDEBUG(D_receive) debug_printf("no EHLO/HELO command was issued\n");
}
+/* Deal with the case of -bs without an IP address */
+
+else if (sender_host_address == NULL)
+ {
+ HDEBUG(D_receive) debug_printf("no client IP address: assume success\n");
+ f.helo_verified = TRUE;
+ }
+
+/* Deal with the more common case when there is a sending IP address */
+
else if (sender_helo_name[0] == '[')
{
- helo_verified = Ustrncmp(sender_helo_name+1, sender_host_address,
+ f.helo_verified = Ustrncmp(sender_helo_name+1, sender_host_address,
Ustrlen(sender_host_address)) == 0;
- #if HAVE_IPV6
- if (!helo_verified)
+#if HAVE_IPV6
+ if (!f.helo_verified)
{
if (strncmpic(sender_host_address, US"::ffff:", 7) == 0)
- helo_verified = Ustrncmp(sender_helo_name + 1,
+ f.helo_verified = Ustrncmp(sender_helo_name + 1,
sender_host_address + 7, Ustrlen(sender_host_address) - 7) == 0;
}
- #endif
+#endif
HDEBUG(D_receive)
- { if (helo_verified) debug_printf("matched host address\n"); }
+ { if (f.helo_verified) debug_printf("matched host address\n"); }
}
/* Do a reverse lookup if one hasn't already given a positive or negative
/* If a host name is known, check it and all its aliases. */
- if (sender_host_name != NULL)
- {
- helo_verified = strcmpic(sender_host_name, sender_helo_name) == 0;
-
- if (helo_verified)
+ if (sender_host_name)
+ if ((f.helo_verified = strcmpic(sender_host_name, sender_helo_name) == 0))
{
+ sender_helo_dnssec = sender_host_dnssec;
HDEBUG(D_receive) debug_printf("matched host name\n");
}
else
{
uschar **aliases = sender_host_aliases;
- while (*aliases != NULL)
- {
- helo_verified = strcmpic(*aliases++, sender_helo_name) == 0;
- if (helo_verified) break;
- }
- HDEBUG(D_receive)
- {
- if (helo_verified)
+ while (*aliases)
+ if ((f.helo_verified = strcmpic(*aliases++, sender_helo_name) == 0))
+ {
+ sender_helo_dnssec = sender_host_dnssec;
+ break;
+ }
+
+ HDEBUG(D_receive) if (f.helo_verified)
debug_printf("matched alias %s\n", *(--aliases));
- }
}
- }
/* Final attempt: try a forward lookup of the helo name */
- if (!helo_verified)
+ if (!f.helo_verified)
{
int rc;
- host_item h;
- h.name = sender_helo_name;
- h.address = NULL;
- h.mx = MX_NONE;
- h.next = NULL;
+ host_item h =
+ {.name = sender_helo_name, .address = NULL, .mx = MX_NONE, .next = NULL};
+ dnssec_domains d =
+ {.request = US"*", .require = US""};
+
HDEBUG(D_receive) debug_printf("getting IP address for %s\n",
sender_helo_name);
- rc = host_find_byname(&h, NULL, NULL, TRUE);
+ rc = host_find_bydns(&h, NULL, HOST_FIND_BY_A | HOST_FIND_BY_AAAA,
+ NULL, NULL, NULL, &d, NULL, NULL);
if (rc == HOST_FOUND || rc == HOST_FOUND_LOCAL)
- {
- host_item *hh = &h;
- while (hh != NULL)
- {
+ for (host_item * hh = &h; hh; hh = hh->next)
if (Ustrcmp(hh->address, sender_host_address) == 0)
{
- helo_verified = TRUE;
+ f.helo_verified = TRUE;
+ if (h.dnssec == DS_YES) sender_helo_dnssec = TRUE;
HDEBUG(D_receive)
- debug_printf("IP address for %s matches calling address\n",
- sender_helo_name);
+ debug_printf("IP address for %s matches calling address\n"
+ "Forward DNS security status: %sverified\n",
+ sender_helo_name, sender_helo_dnssec ? "" : "un");
break;
}
- hh = hh->next;
- }
- }
}
}
-if (!helo_verified) helo_verify_failed = FALSE; /* We've tried ... */
+if (!f.helo_verified) f.helo_verify_failed = TRUE; /* We've tried ... */
return yield;
}
+/*************************************************
+* Send user response message *
+*************************************************/
+
+/* This function is passed a default response code and a user message. It calls
+smtp_message_code() to check and possibly modify the response code, and then
+calls smtp_respond() to transmit the response. I put this into a function
+just to avoid a lot of repetition.
+
+Arguments:
+ code the response code
+ user_msg the user message
+
+Returns: nothing
+*/
+
+static void
+smtp_user_msg(uschar *code, uschar *user_msg)
+{
+int len = 3;
+smtp_message_code(&code, &len, &user_msg, NULL, TRUE);
+smtp_respond(code, len, TRUE, user_msg);
+}
+
+
+
+static int
+smtp_in_auth(auth_instance *au, uschar ** s, uschar ** ss)
+{
+const uschar *set_id = NULL;
+int rc;
+
+/* Run the checking code, passing the remainder of the command line as
+data. Initials the $auth<n> variables as empty. Initialize $0 empty and set
+it as the only set numerical variable. The authenticator may set $auth<n>
+and also set other numeric variables. The $auth<n> variables are preferred
+nowadays; the numerical variables remain for backwards compatibility.
+
+Afterwards, have a go at expanding the set_id string, even if
+authentication failed - for bad passwords it can be useful to log the
+userid. On success, require set_id to expand and exist, and put it in
+authenticated_id. Save this in permanent store, as the working store gets
+reset at HELO, RSET, etc. */
+
+for (int i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL;
+expand_nmax = 0;
+expand_nlength[0] = 0; /* $0 contains nothing */
+
+rc = (au->info->servercode)(au, smtp_cmd_data);
+if (au->set_id) set_id = expand_string(au->set_id);
+expand_nmax = -1; /* Reset numeric variables */
+for (int i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL; /* Reset $auth<n> */
+
+/* The value of authenticated_id is stored in the spool file and printed in
+log lines. It must not contain binary zeros or newline characters. In
+normal use, it never will, but when playing around or testing, this error
+can (did) happen. To guard against this, ensure that the id contains only
+printing characters. */
+
+if (set_id) set_id = string_printing(set_id);
+
+/* For the non-OK cases, set up additional logging data if set_id
+is not empty. */
+
+if (rc != OK)
+ set_id = set_id && *set_id
+ ? string_sprintf(" (set_id=%s)", set_id) : US"";
+
+/* Switch on the result */
+
+switch(rc)
+ {
+ case OK:
+ if (!au->set_id || set_id) /* Complete success */
+ {
+ if (set_id) authenticated_id = string_copy_perm(set_id, TRUE);
+ sender_host_authenticated = au->name;
+ sender_host_auth_pubname = au->public_name;
+ authentication_failed = FALSE;
+ authenticated_fail_id = NULL; /* Impossible to already be set? */
+
+ received_protocol =
+ (sender_host_address ? protocols : protocols_local)
+ [pextend + pauthed + (tls_in.active.sock >= 0 ? pcrpted:0)];
+ *s = *ss = US"235 Authentication succeeded";
+ authenticated_by = au;
+ break;
+ }
+
+ /* Authentication succeeded, but we failed to expand the set_id string.
+ Treat this as a temporary error. */
+
+ auth_defer_msg = expand_string_message;
+ /* Fall through */
+
+ case DEFER:
+ if (set_id) authenticated_fail_id = string_copy_perm(set_id, TRUE);
+ *s = string_sprintf("435 Unable to authenticate at present%s",
+ auth_defer_user_msg);
+ *ss = string_sprintf("435 Unable to authenticate at present%s: %s",
+ set_id, auth_defer_msg);
+ break;
+
+ case BAD64:
+ *s = *ss = US"501 Invalid base64 data";
+ break;
+
+ case CANCELLED:
+ *s = *ss = US"501 Authentication cancelled";
+ break;
+
+ case UNEXPECTED:
+ *s = *ss = US"553 Initial data not expected";
+ break;
+
+ case FAIL:
+ if (set_id) authenticated_fail_id = string_copy_perm(set_id, TRUE);
+ *s = US"535 Incorrect authentication data";
+ *ss = string_sprintf("535 Incorrect authentication data%s", set_id);
+ break;
+
+ default:
+ if (set_id) authenticated_fail_id = string_copy_perm(set_id, TRUE);
+ *s = US"435 Internal error";
+ *ss = string_sprintf("435 Internal error%s: return %d from authentication "
+ "check", set_id, rc);
+ break;
+ }
+
+return rc;
+}
+
+
+
+
+
+static int
+qualify_recipient(uschar ** recipient, uschar * smtp_cmd_data, uschar * tag)
+{
+int rd;
+if (f.allow_unqualified_recipient || strcmpic(*recipient, US"postmaster") == 0)
+ {
+ DEBUG(D_receive) debug_printf("unqualified address %s accepted\n",
+ *recipient);
+ rd = Ustrlen(recipient) + 1;
+ *recipient = rewrite_address_qualify(*recipient, TRUE);
+ return rd;
+ }
+smtp_printf("501 %s: recipient address must contain a domain\r\n", FALSE,
+ smtp_cmd_data);
+log_write(L_smtp_syntax_error,
+ LOG_MAIN|LOG_REJECT, "unqualified %s rejected: <%s> %s%s",
+ tag, *recipient, host_and_ident(TRUE), host_lookup_msg);
+return 0;
+}
+
+
+
+
+static void
+smtp_quit_handler(uschar ** user_msgp, uschar ** log_msgp)
+{
+HAD(SCH_QUIT);
+incomplete_transaction_log(US"QUIT");
+if (acl_smtp_quit)
+ {
+ int rc = acl_check(ACL_WHERE_QUIT, NULL, acl_smtp_quit, user_msgp, log_msgp);
+ if (rc == ERROR)
+ log_write(0, LOG_MAIN|LOG_PANIC, "ACL for QUIT returned ERROR: %s",
+ *log_msgp);
+ }
+
+#ifdef TCP_CORK
+(void) setsockopt(fileno(smtp_out), IPPROTO_TCP, TCP_CORK, US &on, sizeof(on));
+#endif
+
+if (*user_msgp)
+ smtp_respond(US"221", 3, TRUE, *user_msgp);
+else
+ smtp_printf("221 %s closing connection\r\n", FALSE, smtp_active_hostname);
+
+#ifndef DISABLE_TLS
+tls_close(NULL, TLS_SHUTDOWN_NOWAIT);
+#endif
+
+log_write(L_smtp_connection, LOG_MAIN, "%s closed by QUIT",
+ smtp_get_connection_info());
+}
+
+
+static void
+smtp_rset_handler(void)
+{
+HAD(SCH_RSET);
+incomplete_transaction_log(US"RSET");
+smtp_printf("250 Reset OK\r\n", FALSE);
+cmd_list[CMD_LIST_RSET].is_mail_cmd = FALSE;
+}
+
+
+
/*************************************************
* Initialize for SMTP incoming message *
*************************************************/
BOOL discarded = FALSE;
BOOL last_was_rej_mail = FALSE;
BOOL last_was_rcpt = FALSE;
-void *reset_point = store_get(0);
+rmark reset_point = store_mark();
DEBUG(D_receive) debug_printf("smtp_setup_msg entered\n");
TLS between messages (an Exim client may do this if it has messages queued up
for the host). Note: we do NOT reset AUTH at this point. */
-smtp_reset(reset_point);
+reset_point = smtp_reset(reset_point);
message_ended = END_NOTSTARTED;
+chunking_state = f.chunking_offered ? CHUNKING_OFFERED : CHUNKING_NOT_OFFERED;
+
cmd_list[CMD_LIST_RSET].is_mail_cmd = TRUE;
cmd_list[CMD_LIST_HELO].is_mail_cmd = TRUE;
cmd_list[CMD_LIST_EHLO].is_mail_cmd = TRUE;
-#ifdef SUPPORT_TLS
+#ifndef DISABLE_TLS
cmd_list[CMD_LIST_STARTTLS].is_mail_cmd = TRUE;
#endif
/* Set the local signal handler for SIGTERM - it tries to end off tidily */
+had_command_sigterm = 0;
os_non_restarting_signal(SIGTERM, command_sigterm_handler);
/* Batched SMTP is handled in a different function. */
while (done <= 0)
{
- uschar **argv;
+ const uschar **argv;
uschar *etrn_command;
uschar *etrn_serialize_key;
uschar *errmess;
- uschar *user_msg, *log_msg;
+ uschar *log_msg, *smtp_code;
+ uschar *user_msg = NULL;
uschar *recipient = NULL;
uschar *hello = NULL;
- uschar *set_id = NULL;
uschar *s, *ss;
BOOL was_rej_mail = FALSE;
BOOL was_rcpt = FALSE;
void (*oldsignal)(int);
pid_t pid;
int start, end, sender_domain, recipient_domain;
- int ptr, size, rc;
+ int rc;
int c;
- auth_instance *au;
+ uschar *orcpt = NULL;
+ int dsn_flags;
+ gstring * g;
+
+#ifdef AUTH_TLS
+ /* Check once per STARTTLS or SSL-on-connect for a TLS AUTH */
+ if ( tls_in.active.sock >= 0
+ && tls_in.peercert
+ && tls_in.certificate_verified
+ && cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd
+ )
+ {
+ cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd = FALSE;
+
+ for (auth_instance * au = auths; au; au = au->next)
+ if (strcmpic(US"tls", au->driver_name) == 0)
+ {
+ if ( acl_smtp_auth
+ && (rc = acl_check(ACL_WHERE_AUTH, NULL, acl_smtp_auth,
+ &user_msg, &log_msg)) != OK
+ )
+ done = smtp_handle_acl_fail(ACL_WHERE_AUTH, rc, user_msg, log_msg);
+ else
+ {
+ smtp_cmd_data = NULL;
+
+ if (smtp_in_auth(au, &s, &ss) == OK)
+ { DEBUG(D_auth) debug_printf("tls auth succeeded\n"); }
+ else
+ { DEBUG(D_auth) debug_printf("tls auth not succeeded\n"); }
+ }
+ break;
+ }
+ }
+#endif
- switch(smtp_read_command(TRUE))
+#ifdef TCP_QUICKACK
+ if (smtp_in) /* Avoid pure-ACKs while in cmd pingpong phase */
+ (void) setsockopt(fileno(smtp_in), IPPROTO_TCP, TCP_QUICKACK,
+ US &off, sizeof(off));
+#endif
+
+ switch(smtp_read_command(
+#ifdef SUPPORT_PIPE_CONNECT
+ !fl.pipe_connect_acceptable,
+#else
+ TRUE,
+#endif
+ GETC_BUFFER_UNLIMITED))
{
/* The AUTH command is not permitted to occur inside a transaction, and may
- occur successfully only once per connection, and then only when we've
- advertised it. Actually, that isn't quite true. When TLS is started, all
- previous information about a connection must be discarded, so a new AUTH is
- permitted at that time.
+ occur successfully only once per connection. Actually, that isn't quite
+ true. When TLS is started, all previous information about a connection must
+ be discarded, so a new AUTH is permitted at that time.
+
+ AUTH may only be used when it has been advertised. However, it seems that
+ there are clients that send AUTH when it hasn't been advertised, some of
+ them even doing this after HELO. And there are MTAs that accept this. Sigh.
+ So there's a get-out that allows this to happen.
AUTH is initially labelled as a "nonmail command" so that one occurrence
doesn't get counted. We change the label here so that multiple failing
AUTHS will eventually hit the nonmail threshold. */
case AUTH_CMD:
- authentication_failed = TRUE;
- cmd_list[CMD_LIST_AUTH].is_mail_cmd = FALSE;
+ HAD(SCH_AUTH);
+ authentication_failed = TRUE;
+ cmd_list[CMD_LIST_AUTH].is_mail_cmd = FALSE;
+
+ if (!fl.auth_advertised && !f.allow_auth_unadvertised)
+ {
+ done = synprot_error(L_smtp_protocol_error, 503, NULL,
+ US"AUTH command used when not advertised");
+ break;
+ }
+ if (sender_host_authenticated)
+ {
+ done = synprot_error(L_smtp_protocol_error, 503, NULL,
+ US"already authenticated");
+ break;
+ }
+ if (sender_address)
+ {
+ done = synprot_error(L_smtp_protocol_error, 503, NULL,
+ US"not permitted in mail transaction");
+ break;
+ }
+
+ /* Check the ACL */
+
+ if ( acl_smtp_auth
+ && (rc = acl_check(ACL_WHERE_AUTH, NULL, acl_smtp_auth,
+ &user_msg, &log_msg)) != OK
+ )
+ {
+ done = smtp_handle_acl_fail(ACL_WHERE_AUTH, rc, user_msg, log_msg);
+ break;
+ }
+
+ /* Find the name of the requested authentication mechanism. */
+
+ s = smtp_cmd_data;
+ while ((c = *smtp_cmd_data) != 0 && !isspace(c))
+ {
+ if (!isalnum(c) && c != '-' && c != '_')
+ {
+ done = synprot_error(L_smtp_syntax_error, 501, NULL,
+ US"invalid character in authentication mechanism name");
+ goto COMMAND_LOOP;
+ }
+ smtp_cmd_data++;
+ }
+
+ /* If not at the end of the line, we must be at white space. Terminate the
+ name and move the pointer on to any data that may be present. */
+
+ if (*smtp_cmd_data != 0)
+ {
+ *smtp_cmd_data++ = 0;
+ while (isspace(*smtp_cmd_data)) smtp_cmd_data++;
+ }
+
+ /* Search for an authentication mechanism which is configured for use
+ as a server and which has been advertised (unless, sigh, allow_auth_
+ unadvertised is set). */
+
+ {
+ auth_instance * au;
+ for (au = auths; au; au = au->next)
+ if (strcmpic(s, au->public_name) == 0 && au->server &&
+ (au->advertised || f.allow_auth_unadvertised))
+ break;
+
+ if (au)
+ {
+ c = smtp_in_auth(au, &s, &ss);
+
+ smtp_printf("%s\r\n", FALSE, s);
+ if (c != OK)
+ log_write(0, LOG_MAIN|LOG_REJECT, "%s authenticator failed for %s: %s",
+ au->name, host_and_ident(FALSE), ss);
+ }
+ else
+ done = synprot_error(L_smtp_protocol_error, 504, NULL,
+ string_sprintf("%s authentication mechanism not supported", s));
+ }
+
+ break; /* AUTH_CMD */
- if (!auth_advertised)
- {
- done = synprot_error(L_smtp_protocol_error, 503, NULL,
- US"AUTH command used when not advertised");
- break;
- }
- if (sender_host_authenticated != NULL)
- {
- done = synprot_error(L_smtp_protocol_error, 503, NULL,
- US"already authenticated");
- break;
- }
- if (sender_address != NULL)
- {
- done = synprot_error(L_smtp_protocol_error, 503, NULL,
- US"not permitted in mail transaction");
- break;
- }
+ /* The HELO/EHLO commands are permitted to appear in the middle of a
+ session as well as at the beginning. They have the effect of a reset in
+ addition to their other functions. Their absence at the start cannot be
+ taken to be an error.
- /* Check the ACL */
+ RFC 2821 says:
- if (acl_smtp_auth != NULL)
- {
- rc = acl_check(ACL_WHERE_AUTH, NULL, acl_smtp_auth, &user_msg, &log_msg);
- if (rc != OK)
- {
- done = smtp_handle_acl_fail(ACL_WHERE_AUTH, rc, user_msg, log_msg);
- break;
- }
- }
+ If the EHLO command is not acceptable to the SMTP server, 501, 500,
+ or 502 failure replies MUST be returned as appropriate. The SMTP
+ server MUST stay in the same state after transmitting these replies
+ that it was in before the EHLO was received.
- /* Find the name of the requested authentication mechanism. */
+ Therefore, we do not do the reset until after checking the command for
+ acceptability. This change was made for Exim release 4.11. Previously
+ it did the reset first. */
- s = smtp_command_argument;
- while ((c = *smtp_command_argument) != 0 && !isspace(c))
- {
- if (!isalnum(c) && c != '-' && c != '_')
- {
- done = synprot_error(L_smtp_syntax_error, 501, NULL,
- US"invalid character in authentication mechanism name");
- goto COMMAND_LOOP;
- }
- smtp_command_argument++;
- }
+ case HELO_CMD:
+ HAD(SCH_HELO);
+ hello = US"HELO";
+ fl.esmtp = FALSE;
+ goto HELO_EHLO;
- /* If not at the end of the line, we must be at white space. Terminate the
- name and move the pointer on to any data that may be present. */
+ case EHLO_CMD:
+ HAD(SCH_EHLO);
+ hello = US"EHLO";
+ fl.esmtp = TRUE;
- if (*smtp_command_argument != 0)
- {
- *smtp_command_argument++ = 0;
- while (isspace(*smtp_command_argument)) smtp_command_argument++;
- }
+ HELO_EHLO: /* Common code for HELO and EHLO */
+ cmd_list[CMD_LIST_HELO].is_mail_cmd = FALSE;
+ cmd_list[CMD_LIST_EHLO].is_mail_cmd = FALSE;
+
+ /* Reject the HELO if its argument was invalid or non-existent. A
+ successful check causes the argument to be saved in malloc store. */
+
+ if (!check_helo(smtp_cmd_data))
+ {
+ smtp_printf("501 Syntactically invalid %s argument(s)\r\n", FALSE, hello);
+
+ log_write(0, LOG_MAIN|LOG_REJECT, "rejected %s from %s: syntactically "
+ "invalid argument(s): %s", hello, host_and_ident(FALSE),
+ *smtp_cmd_argument == 0 ? US"(no argument given)" :
+ string_printing(smtp_cmd_argument));
+
+ if (++synprot_error_count > smtp_max_synprot_errors)
+ {
+ log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many "
+ "syntax or protocol errors (last command was \"%s\")",
+ host_and_ident(FALSE), string_printing(smtp_cmd_buffer));
+ done = 1;
+ }
+
+ break;
+ }
+
+ /* If sender_host_unknown is true, we have got here via the -bs interface,
+ not called from inetd. Otherwise, we are running an IP connection and the
+ host address will be set. If the helo name is the primary name of this
+ host and we haven't done a reverse lookup, force one now. If helo_required
+ is set, ensure that the HELO name matches the actual host. If helo_verify
+ is set, do the same check, but softly. */
+
+ if (!f.sender_host_unknown)
+ {
+ BOOL old_helo_verified = f.helo_verified;
+ uschar *p = smtp_cmd_data;
+
+ while (*p != 0 && !isspace(*p)) { *p = tolower(*p); p++; }
+ *p = 0;
+
+ /* Force a reverse lookup if HELO quoted something in helo_lookup_domains
+ because otherwise the log can be confusing. */
+
+ if ( !sender_host_name
+ && match_isinlist(sender_helo_name, CUSS &helo_lookup_domains, 0,
+ &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK)
+ (void)host_name_lookup();
+
+ /* Rebuild the fullhost info to include the HELO name (and the real name
+ if it was looked up.) */
+
+ host_build_sender_fullhost(); /* Rebuild */
+ set_process_info("handling%s incoming connection from %s",
+ tls_in.active.sock >= 0 ? " TLS" : "", host_and_ident(FALSE));
+
+ /* Verify if configured. This doesn't give much security, but it does
+ make some people happy to be able to do it. If helo_required is set,
+ (host matches helo_verify_hosts) failure forces rejection. If helo_verify
+ is set (host matches helo_try_verify_hosts), it does not. This is perhaps
+ now obsolescent, since the verification can now be requested selectively
+ at ACL time. */
+
+ f.helo_verified = f.helo_verify_failed = sender_helo_dnssec = FALSE;
+ if (fl.helo_required || fl.helo_verify)
+ {
+ BOOL tempfail = !smtp_verify_helo();
+ if (!f.helo_verified)
+ {
+ if (fl.helo_required)
+ {
+ smtp_printf("%d %s argument does not match calling host\r\n", FALSE,
+ tempfail? 451 : 550, hello);
+ log_write(0, LOG_MAIN|LOG_REJECT, "%srejected \"%s %s\" from %s",
+ tempfail? "temporarily " : "",
+ hello, sender_helo_name, host_and_ident(FALSE));
+ f.helo_verified = old_helo_verified;
+ break; /* End of HELO/EHLO processing */
+ }
+ HDEBUG(D_all) debug_printf("%s verification failed but host is in "
+ "helo_try_verify_hosts\n", hello);
+ }
+ }
+ }
+
+#ifdef SUPPORT_SPF
+ /* set up SPF context */
+ spf_conn_init(sender_helo_name, sender_host_address);
+#endif
- /* Search for an authentication mechanism which is configured for use
- as a server and which has been advertised. */
+ /* Apply an ACL check if one is defined; afterwards, recheck
+ synchronization in case the client started sending in a delay. */
+
+ if (acl_smtp_helo)
+ if ((rc = acl_check(ACL_WHERE_HELO, NULL, acl_smtp_helo,
+ &user_msg, &log_msg)) != OK)
+ {
+ done = smtp_handle_acl_fail(ACL_WHERE_HELO, rc, user_msg, log_msg);
+ sender_helo_name = NULL;
+ host_build_sender_fullhost(); /* Rebuild */
+ break;
+ }
+#ifdef SUPPORT_PIPE_CONNECT
+ else if (!fl.pipe_connect_acceptable && !check_sync())
+#else
+ else if (!check_sync())
+#endif
+ goto SYNC_FAILURE;
+
+ /* Generate an OK reply. The default string includes the ident if present,
+ and also the IP address if present. Reflecting back the ident is intended
+ as a deterrent to mail forgers. For maximum efficiency, and also because
+ some broken systems expect each response to be in a single packet, arrange
+ that the entire reply is sent in one write(). */
+
+ fl.auth_advertised = FALSE;
+ f.smtp_in_pipelining_advertised = FALSE;
+#ifndef DISABLE_TLS
+ fl.tls_advertised = FALSE;
+#endif
+ fl.dsn_advertised = FALSE;
+#ifdef SUPPORT_I18N
+ fl.smtputf8_advertised = FALSE;
+#endif
- for (au = auths; au != NULL; au = au->next)
- {
- if (strcmpic(s, au->public_name) == 0 && au->server &&
- au->advertised) break;
- }
+ smtp_code = US"250 "; /* Default response code plus space*/
+ if (!user_msg)
+ {
+ /* sender_host_name below will be tainted, so save on copy when we hit it */
+ g = string_get_tainted(24, TRUE);
+ g = string_fmt_append(g, "%.3s %s Hello %s%s%s",
+ smtp_code,
+ smtp_active_hostname,
+ sender_ident ? sender_ident : US"",
+ sender_ident ? US" at " : US"",
+ sender_host_name ? sender_host_name : sender_helo_name);
+
+ if (sender_host_address)
+ g = string_fmt_append(g, " [%s]", sender_host_address);
+ }
+
+ /* A user-supplied EHLO greeting may not contain more than one line. Note
+ that the code returned by smtp_message_code() includes the terminating
+ whitespace character. */
- if (au == NULL)
- {
- done = synprot_error(L_smtp_protocol_error, 504, NULL,
- string_sprintf("%s authentication mechanism not supported", s));
- break;
- }
+ else
+ {
+ char *ss;
+ int codelen = 4;
+ smtp_message_code(&smtp_code, &codelen, &user_msg, NULL, TRUE);
+ s = string_sprintf("%.*s%s", codelen, smtp_code, user_msg);
+ if ((ss = strpbrk(CS s, "\r\n")) != NULL)
+ {
+ log_write(0, LOG_MAIN|LOG_PANIC, "EHLO/HELO response must not contain "
+ "newlines: message truncated: %s", string_printing(s));
+ *ss = 0;
+ }
+ g = string_cat(NULL, s);
+ }
+
+ g = string_catn(g, US"\r\n", 2);
+
+ /* If we received EHLO, we must create a multiline response which includes
+ the functions supported. */
+
+ if (fl.esmtp)
+ {
+ g->s[3] = '-';
+
+ /* I'm not entirely happy with this, as an MTA is supposed to check
+ that it has enough room to accept a message of maximum size before
+ it sends this. However, there seems little point in not sending it.
+ The actual size check happens later at MAIL FROM time. By postponing it
+ till then, VRFY and EXPN can be used after EHLO when space is short. */
+
+ if (thismessage_size_limit > 0)
+ g = string_fmt_append(g, "%.3s-SIZE %d\r\n", smtp_code,
+ thismessage_size_limit);
+ else
+ {
+ g = string_catn(g, smtp_code, 3);
+ g = string_catn(g, US"-SIZE\r\n", 7);
+ }
+
+ /* Exim does not do protocol conversion or data conversion. It is 8-bit
+ clean; if it has an 8-bit character in its hand, it just sends it. It
+ cannot therefore specify 8BITMIME and remain consistent with the RFCs.
+ However, some users want this option simply in order to stop MUAs
+ mangling messages that contain top-bit-set characters. It is therefore
+ provided as an option. */
+
+ if (accept_8bitmime)
+ {
+ g = string_catn(g, smtp_code, 3);
+ g = string_catn(g, US"-8BITMIME\r\n", 11);
+ }
+
+ /* Advertise DSN support if configured to do so. */
+ if (verify_check_host(&dsn_advertise_hosts) != FAIL)
+ {
+ g = string_catn(g, smtp_code, 3);
+ g = string_catn(g, US"-DSN\r\n", 6);
+ fl.dsn_advertised = TRUE;
+ }
+
+ /* Advertise ETRN/VRFY/EXPN if there's are ACL checking whether a host is
+ permitted to issue them; a check is made when any host actually tries. */
+
+ if (acl_smtp_etrn)
+ {
+ g = string_catn(g, smtp_code, 3);
+ g = string_catn(g, US"-ETRN\r\n", 7);
+ }
+ if (acl_smtp_vrfy)
+ {
+ g = string_catn(g, smtp_code, 3);
+ g = string_catn(g, US"-VRFY\r\n", 7);
+ }
+ if (acl_smtp_expn)
+ {
+ g = string_catn(g, smtp_code, 3);
+ g = string_catn(g, US"-EXPN\r\n", 7);
+ }
+
+ /* Exim is quite happy with pipelining, so let the other end know that
+ it is safe to use it, unless advertising is disabled. */
+
+ if ( f.pipelining_enable
+ && verify_check_host(&pipelining_advertise_hosts) == OK)
+ {
+ g = string_catn(g, smtp_code, 3);
+ g = string_catn(g, US"-PIPELINING\r\n", 13);
+ sync_cmd_limit = NON_SYNC_CMD_PIPELINING;
+ f.smtp_in_pipelining_advertised = TRUE;
+
+#ifdef SUPPORT_PIPE_CONNECT
+ if (fl.pipe_connect_acceptable)
+ {
+ f.smtp_in_early_pipe_advertised = TRUE;
+ g = string_catn(g, smtp_code, 3);
+ g = string_catn(g, US"-" EARLY_PIPE_FEATURE_NAME "\r\n", EARLY_PIPE_FEATURE_LEN+3);
+ }
+#endif
+ }
- /* Run the checking code, passing the remainder of the command
- line as data. Initialize $0 empty. The authenticator may set up
- other numeric variables. Afterwards, have a go at expanding the set_id
- string, even if authentication failed - for bad passwords it can be useful
- to log the userid. On success, require set_id to expand and exist, and
- put it in authenticated_id. Save this in permanent store, as the working
- store gets reset at HELO, RSET, etc. */
- expand_nmax = 0;
- expand_nlength[0] = 0; /* $0 contains nothing */
+ /* If any server authentication mechanisms are configured, advertise
+ them if the current host is in auth_advertise_hosts. The problem with
+ advertising always is that some clients then require users to
+ authenticate (and aren't configurable otherwise) even though it may not
+ be necessary (e.g. if the host is in host_accept_relay).
- c = (au->info->servercode)(au, smtp_command_argument);
- if (au->set_id != NULL) set_id = expand_string(au->set_id);
- expand_nmax = -1; /* Reset numeric variables */
+ RFC 2222 states that SASL mechanism names contain only upper case
+ letters, so output the names in upper case, though we actually recognize
+ them in either case in the AUTH command. */
- /* The value of authenticated_id is stored in the spool file and printed in
- log lines. It must not contain binary zeros or newline characters. In
- normal use, it never will, but when playing around or testing, this error
- can (did) happen. To guard against this, ensure that the id contains only
- printing characters. */
+ if ( auths
+#ifdef AUTH_TLS
+ && !sender_host_authenticated
+#endif
+ && verify_check_host(&auth_advertise_hosts) == OK
+ )
+ {
+ BOOL first = TRUE;
+ for (auth_instance * au = auths; au; au = au->next)
+ {
+ au->advertised = FALSE;
+ if (au->server)
+ {
+ DEBUG(D_auth+D_expand) debug_printf_indent(
+ "Evaluating advertise_condition for %s athenticator\n",
+ au->public_name);
+ if ( !au->advertise_condition
+ || expand_check_condition(au->advertise_condition, au->name,
+ US"authenticator")
+ )
+ {
+ int saveptr;
+ if (first)
+ {
+ g = string_catn(g, smtp_code, 3);
+ g = string_catn(g, US"-AUTH", 5);
+ first = FALSE;
+ fl.auth_advertised = TRUE;
+ }
+ saveptr = g->ptr;
+ g = string_catn(g, US" ", 1);
+ g = string_cat (g, au->public_name);
+ while (++saveptr < g->ptr) g->s[saveptr] = toupper(g->s[saveptr]);
+ au->advertised = TRUE;
+ }
+ }
+ }
+
+ if (!first) g = string_catn(g, US"\r\n", 2);
+ }
+
+ /* RFC 3030 CHUNKING */
+
+ if (verify_check_host(&chunking_advertise_hosts) != FAIL)
+ {
+ g = string_catn(g, smtp_code, 3);
+ g = string_catn(g, US"-CHUNKING\r\n", 11);
+ f.chunking_offered = TRUE;
+ chunking_state = CHUNKING_OFFERED;
+ }
+
+ /* Advertise TLS (Transport Level Security) aka SSL (Secure Socket Layer)
+ if it has been included in the binary, and the host matches
+ tls_advertise_hosts. We must *not* advertise if we are already in a
+ secure connection. */
+
+#ifndef DISABLE_TLS
+ if (tls_in.active.sock < 0 &&
+ verify_check_host(&tls_advertise_hosts) != FAIL)
+ {
+ g = string_catn(g, smtp_code, 3);
+ g = string_catn(g, US"-STARTTLS\r\n", 11);
+ fl.tls_advertised = TRUE;
+ }
+#endif
- if (set_id != NULL) set_id = string_printing(set_id);
+#ifndef DISABLE_PRDR
+ /* Per Recipient Data Response, draft by Eric A. Hall extending RFC */
+ if (prdr_enable)
+ {
+ g = string_catn(g, smtp_code, 3);
+ g = string_catn(g, US"-PRDR\r\n", 7);
+ }
+#endif
- /* For the non-OK cases, set up additional logging data if set_id
- is not empty. */
+#ifdef SUPPORT_I18N
+ if ( accept_8bitmime
+ && verify_check_host(&smtputf8_advertise_hosts) != FAIL)
+ {
+ g = string_catn(g, smtp_code, 3);
+ g = string_catn(g, US"-SMTPUTF8\r\n", 11);
+ fl.smtputf8_advertised = TRUE;
+ }
+#endif
- if (c != OK)
- {
- if (set_id != NULL && *set_id != 0)
- set_id = string_sprintf(" (set_id=%s)", set_id);
- else set_id = US"";
- }
+ /* Finish off the multiline reply with one that is always available. */
- /* Switch on the result */
+ g = string_catn(g, smtp_code, 3);
+ g = string_catn(g, US" HELP\r\n", 7);
+ }
- switch(c)
- {
- case OK:
- if (au->set_id == NULL || set_id != NULL) /* Complete success */
- {
- if (set_id != NULL) authenticated_id = string_copy_malloc(set_id);
- sender_host_authenticated = au->name;
- authentication_failed = FALSE;
- received_protocol =
- protocols[pextend + pauthed + ((tls_active >= 0)? pcrpted:0)] +
- ((sender_host_address != NULL)? pnlocal : 0);
- s = ss = US"235 Authentication succeeded";
- authenticated_by = au;
- break;
- }
+ /* Terminate the string (for debug), write it, and note that HELO/EHLO
+ has been seen. */
- /* Authentication succeeded, but we failed to expand the set_id string.
- Treat this as a temporary error. */
+#ifndef DISABLE_TLS
+ if (tls_in.active.sock >= 0)
+ (void)tls_write(NULL, g->s, g->ptr,
+# ifdef SUPPORT_PIPE_CONNECT
+ fl.pipe_connect_acceptable && pipeline_connect_sends());
+# else
+ FALSE);
+# endif
+ else
+#endif
- auth_defer_msg = expand_string_message;
- /* Fall through */
+ {
+ int i = fwrite(g->s, 1, g->ptr, smtp_out); i = i; /* compiler quietening */
+ }
+ DEBUG(D_receive)
+ {
+ uschar *cr;
+
+ (void) string_from_gstring(g);
+ while ((cr = Ustrchr(g->s, '\r')) != NULL) /* lose CRs */
+ memmove(cr, cr + 1, (g->ptr--) - (cr - g->s));
+ debug_printf("SMTP>> %s", g->s);
+ }
+ fl.helo_seen = TRUE;
+
+ /* Reset the protocol and the state, abandoning any previous message. */
+ received_protocol =
+ (sender_host_address ? protocols : protocols_local)
+ [ (fl.esmtp
+ ? pextend + (sender_host_authenticated ? pauthed : 0)
+ : pnormal)
+ + (tls_in.active.sock >= 0 ? pcrpted : 0)
+ ];
+ cancel_cutthrough_connection(TRUE, US"sent EHLO response");
+ reset_point = smtp_reset(reset_point);
+ toomany = FALSE;
+ break; /* HELO/EHLO */
- case DEFER:
- s = string_sprintf("435 Unable to authenticate at present%s",
- auth_defer_user_msg);
- ss = string_sprintf("435 Unable to authenticate at present%s: %s",
- set_id, auth_defer_msg);
- break;
- case BAD64:
- s = ss = US"501 Invalid base64 data";
- break;
+ /* The MAIL command requires an address as an operand. All we do
+ here is to parse it for syntactic correctness. The form "<>" is
+ a special case which converts into an empty string. The start/end
+ pointers in the original are not used further for this address, as
+ it is the canonical extracted address which is all that is kept. */
- case CANCELLED:
- s = ss = US"501 Authentication cancelled";
- break;
+ case MAIL_CMD:
+ HAD(SCH_MAIL);
+ smtp_mailcmd_count++; /* Count for limit and ratelimit */
+ was_rej_mail = TRUE; /* Reset if accepted */
+ env_mail_type_t * mail_args; /* Sanity check & validate args */
+
+ if (fl.helo_required && !fl.helo_seen)
+ {
+ smtp_printf("503 HELO or EHLO required\r\n", FALSE);
+ log_write(0, LOG_MAIN|LOG_REJECT, "rejected MAIL from %s: no "
+ "HELO/EHLO given", host_and_ident(FALSE));
+ break;
+ }
+
+ if (sender_address)
+ {
+ done = synprot_error(L_smtp_protocol_error, 503, NULL,
+ US"sender already given");
+ break;
+ }
+
+ if (!*smtp_cmd_data)
+ {
+ done = synprot_error(L_smtp_protocol_error, 501, NULL,
+ US"MAIL must have an address operand");
+ break;
+ }
+
+ /* Check to see if the limit for messages per connection would be
+ exceeded by accepting further messages. */
+
+ if (smtp_accept_max_per_connection > 0 &&
+ smtp_mailcmd_count > smtp_accept_max_per_connection)
+ {
+ smtp_printf("421 too many messages in this connection\r\n", FALSE);
+ log_write(0, LOG_MAIN|LOG_REJECT, "rejected MAIL command %s: too many "
+ "messages in one connection", host_and_ident(TRUE));
+ break;
+ }
+
+ /* Reset for start of message - even if this is going to fail, we
+ obviously need to throw away any previous data. */
+
+ cancel_cutthrough_connection(TRUE, US"MAIL received");
+ reset_point = smtp_reset(reset_point);
+ toomany = FALSE;
+ sender_data = recipient_data = NULL;
+
+ /* Loop, checking for ESMTP additions to the MAIL FROM command. */
+
+ if (fl.esmtp) for(;;)
+ {
+ uschar *name, *value, *end;
+ unsigned long int size;
+ BOOL arg_error = FALSE;
+
+ if (!extract_option(&name, &value)) break;
+
+ for (mail_args = env_mail_type_list;
+ mail_args->value != ENV_MAIL_OPT_NULL;
+ mail_args++
+ )
+ if (strcmpic(name, mail_args->name) == 0)
+ break;
+ if (mail_args->need_value && strcmpic(value, US"") == 0)
+ break;
+
+ switch(mail_args->value)
+ {
+ /* Handle SIZE= by reading the value. We don't do the check till later,
+ in order to be able to log the sender address on failure. */
+ case ENV_MAIL_OPT_SIZE:
+ if (((size = Ustrtoul(value, &end, 10)), *end == 0))
+ {
+ if ((size == ULONG_MAX && errno == ERANGE) || size > INT_MAX)
+ size = INT_MAX;
+ message_size = (int)size;
+ }
+ else
+ arg_error = TRUE;
+ break;
+
+ /* If this session was initiated with EHLO and accept_8bitmime is set,
+ Exim will have indicated that it supports the BODY=8BITMIME option. In
+ fact, it does not support this according to the RFCs, in that it does not
+ take any special action for forwarding messages containing 8-bit
+ characters. That is why accept_8bitmime is not the default setting, but
+ some sites want the action that is provided. We recognize both "8BITMIME"
+ and "7BIT" as body types, but take no action. */
+ case ENV_MAIL_OPT_BODY:
+ if (accept_8bitmime) {
+ if (strcmpic(value, US"8BITMIME") == 0)
+ body_8bitmime = 8;
+ else if (strcmpic(value, US"7BIT") == 0)
+ body_8bitmime = 7;
+ else
+ {
+ body_8bitmime = 0;
+ done = synprot_error(L_smtp_syntax_error, 501, NULL,
+ US"invalid data for BODY");
+ goto COMMAND_LOOP;
+ }
+ DEBUG(D_receive) debug_printf("8BITMIME: %d\n", body_8bitmime);
+ break;
+ }
+ arg_error = TRUE;
+ break;
+
+ /* Handle the two DSN options, but only if configured to do so (which
+ will have caused "DSN" to be given in the EHLO response). The code itself
+ is included only if configured in at build time. */
+
+ case ENV_MAIL_OPT_RET:
+ if (fl.dsn_advertised)
+ {
+ /* Check if RET has already been set */
+ if (dsn_ret > 0)
+ {
+ done = synprot_error(L_smtp_syntax_error, 501, NULL,
+ US"RET can be specified once only");
+ goto COMMAND_LOOP;
+ }
+ dsn_ret = strcmpic(value, US"HDRS") == 0
+ ? dsn_ret_hdrs
+ : strcmpic(value, US"FULL") == 0
+ ? dsn_ret_full
+ : 0;
+ DEBUG(D_receive) debug_printf("DSN_RET: %d\n", dsn_ret);
+ /* Check for invalid invalid value, and exit with error */
+ if (dsn_ret == 0)
+ {
+ done = synprot_error(L_smtp_syntax_error, 501, NULL,
+ US"Value for RET is invalid");
+ goto COMMAND_LOOP;
+ }
+ }
+ break;
+ case ENV_MAIL_OPT_ENVID:
+ if (fl.dsn_advertised)
+ {
+ /* Check if the dsn envid has been already set */
+ if (dsn_envid)
+ {
+ done = synprot_error(L_smtp_syntax_error, 501, NULL,
+ US"ENVID can be specified once only");
+ goto COMMAND_LOOP;
+ }
+ dsn_envid = string_copy(value);
+ DEBUG(D_receive) debug_printf("DSN_ENVID: %s\n", dsn_envid);
+ }
+ break;
+
+ /* Handle the AUTH extension. If the value given is not "<>" and either
+ the ACL says "yes" or there is no ACL but the sending host is
+ authenticated, we set it up as the authenticated sender. However, if the
+ authenticator set a condition to be tested, we ignore AUTH on MAIL unless
+ the condition is met. The value of AUTH is an xtext, which means that +,
+ = and cntrl chars are coded in hex; however "<>" is unaffected by this
+ coding. */
+ case ENV_MAIL_OPT_AUTH:
+ if (Ustrcmp(value, "<>") != 0)
+ {
+ int rc;
+ uschar *ignore_msg;
+
+ if (auth_xtextdecode(value, &authenticated_sender) < 0)
+ {
+ /* Put back terminator overrides for error message */
+ value[-1] = '=';
+ name[-1] = ' ';
+ done = synprot_error(L_smtp_syntax_error, 501, NULL,
+ US"invalid data for AUTH");
+ goto COMMAND_LOOP;
+ }
+ if (!acl_smtp_mailauth)
+ {
+ ignore_msg = US"client not authenticated";
+ rc = sender_host_authenticated ? OK : FAIL;
+ }
+ else
+ {
+ ignore_msg = US"rejected by ACL";
+ rc = acl_check(ACL_WHERE_MAILAUTH, NULL, acl_smtp_mailauth,
+ &user_msg, &log_msg);
+ }
+
+ switch (rc)
+ {
+ case OK:
+ if (authenticated_by == NULL ||
+ authenticated_by->mail_auth_condition == NULL ||
+ expand_check_condition(authenticated_by->mail_auth_condition,
+ authenticated_by->name, US"authenticator"))
+ break; /* Accept the AUTH */
+
+ ignore_msg = US"server_mail_auth_condition failed";
+ if (authenticated_id != NULL)
+ ignore_msg = string_sprintf("%s: authenticated ID=\"%s\"",
+ ignore_msg, authenticated_id);
+
+ /* Fall through */
+
+ case FAIL:
+ authenticated_sender = NULL;
+ log_write(0, LOG_MAIN, "ignoring AUTH=%s from %s (%s)",
+ value, host_and_ident(TRUE), ignore_msg);
+ break;
+
+ /* Should only get DEFER or ERROR here. Put back terminator
+ overrides for error message */
+
+ default:
+ value[-1] = '=';
+ name[-1] = ' ';
+ (void)smtp_handle_acl_fail(ACL_WHERE_MAILAUTH, rc, user_msg,
+ log_msg);
+ goto COMMAND_LOOP;
+ }
+ }
+ break;
+
+#ifndef DISABLE_PRDR
+ case ENV_MAIL_OPT_PRDR:
+ if (prdr_enable)
+ prdr_requested = TRUE;
+ break;
+#endif
- case UNEXPECTED:
- s = ss = US"553 Initial data not expected";
- break;
+#ifdef SUPPORT_I18N
+ case ENV_MAIL_OPT_UTF8:
+ if (!fl.smtputf8_advertised)
+ {
+ done = synprot_error(L_smtp_syntax_error, 501, NULL,
+ US"SMTPUTF8 used when not advertised");
+ goto COMMAND_LOOP;
+ }
+
+ DEBUG(D_receive) debug_printf("smtputf8 requested\n");
+ message_smtputf8 = allow_utf8_domains = TRUE;
+ if (Ustrncmp(received_protocol, US"utf8", 4) != 0)
+ {
+ int old_pool = store_pool;
+ store_pool = POOL_PERM;
+ received_protocol = string_sprintf("utf8%s", received_protocol);
+ store_pool = old_pool;
+ }
+ break;
+#endif
- case FAIL:
- s = US"535 Incorrect authentication data";
- ss = string_sprintf("535 Incorrect authentication data%s", set_id);
+ /* No valid option. Stick back the terminator characters and break
+ the loop. Do the name-terminator second as extract_option sets
+ value==name when it found no equal-sign.
+ An error for a malformed address will occur. */
+ case ENV_MAIL_OPT_NULL:
+ value[-1] = '=';
+ name[-1] = ' ';
+ arg_error = TRUE;
+ break;
+
+ default: assert(0);
+ }
+ /* Break out of for loop if switch() had bad argument or
+ when start of the email address is reached */
+ if (arg_error) break;
+ }
+
+ /* If we have passed the threshold for rate limiting, apply the current
+ delay, and update it for next time, provided this is a limited host. */
+
+ if (smtp_mailcmd_count > smtp_rlm_threshold &&
+ verify_check_host(&smtp_ratelimit_hosts) == OK)
+ {
+ DEBUG(D_receive) debug_printf("rate limit MAIL: delay %.3g sec\n",
+ smtp_delay_mail/1000.0);
+ millisleep((int)smtp_delay_mail);
+ smtp_delay_mail *= smtp_rlm_factor;
+ if (smtp_delay_mail > (double)smtp_rlm_limit)
+ smtp_delay_mail = (double)smtp_rlm_limit;
+ }
+
+ /* Now extract the address, first applying any SMTP-time rewriting. The
+ TRUE flag allows "<>" as a sender address. */
+
+ raw_sender = rewrite_existflags & rewrite_smtp
+ ? rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"",
+ global_rewrite_rules)
+ : smtp_cmd_data;
+
+ raw_sender =
+ parse_extract_address(raw_sender, &errmess, &start, &end, &sender_domain,
+ TRUE);
+
+ if (!raw_sender)
+ {
+ done = synprot_error(L_smtp_syntax_error, 501, smtp_cmd_data, errmess);
+ break;
+ }
+
+ sender_address = raw_sender;
+
+ /* If there is a configured size limit for mail, check that this message
+ doesn't exceed it. The check is postponed to this point so that the sender
+ can be logged. */
+
+ if (thismessage_size_limit > 0 && message_size > thismessage_size_limit)
+ {
+ smtp_printf("552 Message size exceeds maximum permitted\r\n", FALSE);
+ log_write(L_size_reject,
+ LOG_MAIN|LOG_REJECT, "rejected MAIL FROM:<%s> %s: "
+ "message too big: size%s=%d max=%d",
+ sender_address,
+ host_and_ident(TRUE),
+ (message_size == INT_MAX)? ">" : "",
+ message_size,
+ thismessage_size_limit);
+ sender_address = NULL;
+ break;
+ }
+
+ /* Check there is enough space on the disk unless configured not to.
+ When smtp_check_spool_space is set, the check is for thismessage_size_limit
+ plus the current message - i.e. we accept the message only if it won't
+ reduce the space below the threshold. Add 5000 to the size to allow for
+ overheads such as the Received: line and storing of recipients, etc.
+ By putting the check here, even when SIZE is not given, it allow VRFY
+ and EXPN etc. to be used when space is short. */
+
+ if (!receive_check_fs(
+ (smtp_check_spool_space && message_size >= 0)?
+ message_size + 5000 : 0))
+ {
+ smtp_printf("452 Space shortage, please try later\r\n", FALSE);
+ sender_address = NULL;
+ break;
+ }
+
+ /* If sender_address is unqualified, reject it, unless this is a locally
+ generated message, or the sending host or net is permitted to send
+ unqualified addresses - typically local machines behaving as MUAs -
+ in which case just qualify the address. The flag is set above at the start
+ of the SMTP connection. */
+
+ if (!sender_domain && *sender_address)
+ if (f.allow_unqualified_sender)
+ {
+ sender_domain = Ustrlen(sender_address) + 1;
+ sender_address = rewrite_address_qualify(sender_address, FALSE);
+ DEBUG(D_receive) debug_printf("unqualified address %s accepted\n",
+ raw_sender);
+ }
+ else
+ {
+ smtp_printf("501 %s: sender address must contain a domain\r\n", FALSE,
+ smtp_cmd_data);
+ log_write(L_smtp_syntax_error,
+ LOG_MAIN|LOG_REJECT,
+ "unqualified sender rejected: <%s> %s%s",
+ raw_sender,
+ host_and_ident(TRUE),
+ host_lookup_msg);
+ sender_address = NULL;
+ break;
+ }
+
+ /* Apply an ACL check if one is defined, before responding. Afterwards,
+ when pipelining is not advertised, do another sync check in case the ACL
+ delayed and the client started sending in the meantime. */
+
+ if (acl_smtp_mail)
+ {
+ rc = acl_check(ACL_WHERE_MAIL, NULL, acl_smtp_mail, &user_msg, &log_msg);
+ if (rc == OK && !f.smtp_in_pipelining_advertised && !check_sync())
+ goto SYNC_FAILURE;
+ }
+ else
+ rc = OK;
+
+ if (rc == OK || rc == DISCARD)
+ {
+ BOOL more = pipeline_response();
+
+ if (!user_msg)
+ smtp_printf("%s%s%s", more, US"250 OK",
+ #ifndef DISABLE_PRDR
+ prdr_requested ? US", PRDR Requested" : US"",
+ #else
+ US"",
+ #endif
+ US"\r\n");
+ else
+ {
+ #ifndef DISABLE_PRDR
+ if (prdr_requested)
+ user_msg = string_sprintf("%s%s", user_msg, US", PRDR Requested");
+ #endif
+ smtp_user_msg(US"250", user_msg);
+ }
+ smtp_delay_rcpt = smtp_rlr_base;
+ f.recipients_discarded = (rc == DISCARD);
+ was_rej_mail = FALSE;
+ }
+ else
+ {
+ done = smtp_handle_acl_fail(ACL_WHERE_MAIL, rc, user_msg, log_msg);
+ sender_address = NULL;
+ }
break;
- default:
- s = US"435 Internal error";
- ss = string_sprintf("435 Internal error%s: return %d from authentication "
- "check", set_id, c);
- break;
- }
- smtp_printf("%s\r\n", s);
- if (c != OK)
- log_write(0, LOG_MAIN|LOG_REJECT, "%s authenticator failed for %s: %s",
- au->name, host_and_ident(FALSE), ss);
+ /* The RCPT command requires an address as an operand. There may be any
+ number of RCPT commands, specifying multiple recipients. We build them all
+ into a data structure. The start/end values given by parse_extract_address
+ are not used, as we keep only the extracted address. */
- break; /* AUTH_CMD */
+ case RCPT_CMD:
+ HAD(SCH_RCPT);
+ rcpt_count++;
+ was_rcpt = fl.rcpt_in_progress = TRUE;
- /* The HELO/EHLO commands are permitted to appear in the middle of a
- session as well as at the beginning. They have the effect of a reset in
- addition to their other functions. Their absence at the start cannot be
- taken to be an error.
+ /* There must be a sender address; if the sender was rejected and
+ pipelining was advertised, we assume the client was pipelining, and do not
+ count this as a protocol error. Reset was_rej_mail so that further RCPTs
+ get the same treatment. */
- RFC 2821 says:
+ if (sender_address == NULL)
+ {
+ if (f.smtp_in_pipelining_advertised && last_was_rej_mail)
+ {
+ smtp_printf("503 sender not yet given\r\n", FALSE);
+ was_rej_mail = TRUE;
+ }
+ else
+ {
+ done = synprot_error(L_smtp_protocol_error, 503, NULL,
+ US"sender not yet given");
+ was_rcpt = FALSE; /* Not a valid RCPT */
+ }
+ rcpt_fail_count++;
+ break;
+ }
+
+ /* Check for an operand */
+
+ if (smtp_cmd_data[0] == 0)
+ {
+ done = synprot_error(L_smtp_syntax_error, 501, NULL,
+ US"RCPT must have an address operand");
+ rcpt_fail_count++;
+ break;
+ }
+
+ /* Set the DSN flags orcpt and dsn_flags from the session*/
+ orcpt = NULL;
+ dsn_flags = 0;
+
+ if (fl.esmtp) for(;;)
+ {
+ uschar *name, *value;
+
+ if (!extract_option(&name, &value))
+ break;
+
+ if (fl.dsn_advertised && strcmpic(name, US"ORCPT") == 0)
+ {
+ /* Check whether orcpt has been already set */
+ if (orcpt)
+ {
+ done = synprot_error(L_smtp_syntax_error, 501, NULL,
+ US"ORCPT can be specified once only");
+ goto COMMAND_LOOP;
+ }
+ orcpt = string_copy(value);
+ DEBUG(D_receive) debug_printf("DSN orcpt: %s\n", orcpt);
+ }
+
+ else if (fl.dsn_advertised && strcmpic(name, US"NOTIFY") == 0)
+ {
+ /* Check if the notify flags have been already set */
+ if (dsn_flags > 0)
+ {
+ done = synprot_error(L_smtp_syntax_error, 501, NULL,
+ US"NOTIFY can be specified once only");
+ goto COMMAND_LOOP;
+ }
+ if (strcmpic(value, US"NEVER") == 0)
+ dsn_flags |= rf_notify_never;
+ else
+ {
+ uschar *p = value;
+ while (*p != 0)
+ {
+ uschar *pp = p;
+ while (*pp != 0 && *pp != ',') pp++;
+ if (*pp == ',') *pp++ = 0;
+ if (strcmpic(p, US"SUCCESS") == 0)
+ {
+ DEBUG(D_receive) debug_printf("DSN: Setting notify success\n");
+ dsn_flags |= rf_notify_success;
+ }
+ else if (strcmpic(p, US"FAILURE") == 0)
+ {
+ DEBUG(D_receive) debug_printf("DSN: Setting notify failure\n");
+ dsn_flags |= rf_notify_failure;
+ }
+ else if (strcmpic(p, US"DELAY") == 0)
+ {
+ DEBUG(D_receive) debug_printf("DSN: Setting notify delay\n");
+ dsn_flags |= rf_notify_delay;
+ }
+ else
+ {
+ /* Catch any strange values */
+ done = synprot_error(L_smtp_syntax_error, 501, NULL,
+ US"Invalid value for NOTIFY parameter");
+ goto COMMAND_LOOP;
+ }
+ p = pp;
+ }
+ DEBUG(D_receive) debug_printf("DSN Flags: %x\n", dsn_flags);
+ }
+ }
+
+ /* Unknown option. Stick back the terminator characters and break
+ the loop. An error for a malformed address will occur. */
+
+ else
+ {
+ DEBUG(D_receive) debug_printf("Invalid RCPT option: %s : %s\n", name, value);
+ name[-1] = ' ';
+ value[-1] = '=';
+ break;
+ }
+ }
+
+ /* Apply SMTP rewriting then extract the working address. Don't allow "<>"
+ as a recipient address */
+
+ recipient = rewrite_existflags & rewrite_smtp
+ ? rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"",
+ global_rewrite_rules)
+ : smtp_cmd_data;
+
+ if (!(recipient = parse_extract_address(recipient, &errmess, &start, &end,
+ &recipient_domain, FALSE)))
+ {
+ done = synprot_error(L_smtp_syntax_error, 501, smtp_cmd_data, errmess);
+ rcpt_fail_count++;
+ break;
+ }
+
+ /* If the recipient address is unqualified, reject it, unless this is a
+ locally generated message. However, unqualified addresses are permitted
+ from a configured list of hosts and nets - typically when behaving as
+ MUAs rather than MTAs. Sad that SMTP is used for both types of traffic,
+ really. The flag is set at the start of the SMTP connection.
+
+ RFC 1123 talks about supporting "the reserved mailbox postmaster"; I always
+ assumed this meant "reserved local part", but the revision of RFC 821 and
+ friends now makes it absolutely clear that it means *mailbox*. Consequently
+ we must always qualify this address, regardless. */
+
+ if (!recipient_domain)
+ if (!(recipient_domain = qualify_recipient(&recipient, smtp_cmd_data,
+ US"recipient")))
+ {
+ rcpt_fail_count++;
+ break;
+ }
+
+ /* Check maximum allowed */
+
+ if (rcpt_count > recipients_max && recipients_max > 0)
+ {
+ if (recipients_max_reject)
+ {
+ rcpt_fail_count++;
+ smtp_printf("552 too many recipients\r\n", FALSE);
+ if (!toomany)
+ log_write(0, LOG_MAIN|LOG_REJECT, "too many recipients: message "
+ "rejected: sender=<%s> %s", sender_address, host_and_ident(TRUE));
+ }
+ else
+ {
+ rcpt_defer_count++;
+ smtp_printf("452 too many recipients\r\n", FALSE);
+ if (!toomany)
+ log_write(0, LOG_MAIN|LOG_REJECT, "too many recipients: excess "
+ "temporarily rejected: sender=<%s> %s", sender_address,
+ host_and_ident(TRUE));
+ }
+
+ toomany = TRUE;
+ break;
+ }
+
+ /* If we have passed the threshold for rate limiting, apply the current
+ delay, and update it for next time, provided this is a limited host. */
+
+ if (rcpt_count > smtp_rlr_threshold &&
+ verify_check_host(&smtp_ratelimit_hosts) == OK)
+ {
+ DEBUG(D_receive) debug_printf("rate limit RCPT: delay %.3g sec\n",
+ smtp_delay_rcpt/1000.0);
+ millisleep((int)smtp_delay_rcpt);
+ smtp_delay_rcpt *= smtp_rlr_factor;
+ if (smtp_delay_rcpt > (double)smtp_rlr_limit)
+ smtp_delay_rcpt = (double)smtp_rlr_limit;
+ }
+
+ /* If the MAIL ACL discarded all the recipients, we bypass ACL checking
+ for them. Otherwise, check the access control list for this recipient. As
+ there may be a delay in this, re-check for a synchronization error
+ afterwards, unless pipelining was advertised. */
+
+ if (f.recipients_discarded)
+ rc = DISCARD;
+ else
+ if ( (rc = acl_check(ACL_WHERE_RCPT, recipient, acl_smtp_rcpt, &user_msg,
+ &log_msg)) == OK
+ && !f.smtp_in_pipelining_advertised && !check_sync())
+ goto SYNC_FAILURE;
+
+ /* The ACL was happy */
+
+ if (rc == OK)
+ {
+ BOOL more = pipeline_response();
+
+ if (user_msg)
+ smtp_user_msg(US"250", user_msg);
+ else
+ smtp_printf("250 Accepted\r\n", more);
+ receive_add_recipient(recipient, -1);
+
+ /* Set the dsn flags in the recipients_list */
+ recipients_list[recipients_count-1].orcpt = orcpt;
+ recipients_list[recipients_count-1].dsn_flags = dsn_flags;
+
+ DEBUG(D_receive) debug_printf("DSN: orcpt: %s flags: %d\n",
+ recipients_list[recipients_count-1].orcpt,
+ recipients_list[recipients_count-1].dsn_flags);
+ }
+
+ /* The recipient was discarded */
+
+ else if (rc == DISCARD)
+ {
+ if (user_msg)
+ smtp_user_msg(US"250", user_msg);
+ else
+ smtp_printf("250 Accepted\r\n", FALSE);
+ rcpt_fail_count++;
+ discarded = TRUE;
+ log_write(0, LOG_MAIN|LOG_REJECT, "%s F=<%s> RCPT %s: "
+ "discarded by %s ACL%s%s", host_and_ident(TRUE),
+ sender_address_unrewritten? sender_address_unrewritten : sender_address,
+ smtp_cmd_argument, f.recipients_discarded? "MAIL" : "RCPT",
+ log_msg ? US": " : US"", log_msg ? log_msg : US"");
+ }
+
+ /* Either the ACL failed the address, or it was deferred. */
- If the EHLO command is not acceptable to the SMTP server, 501, 500,
- or 502 failure replies MUST be returned as appropriate. The SMTP
- server MUST stay in the same state after transmitting these replies
- that it was in before the EHLO was received.
+ else
+ {
+ if (rc == FAIL) rcpt_fail_count++; else rcpt_defer_count++;
+ done = smtp_handle_acl_fail(ACL_WHERE_RCPT, rc, user_msg, log_msg);
+ }
+ break;
- Therefore, we do not do the reset until after checking the command for
- acceptability. This change was made for Exim release 4.11. Previously
- it did the reset first. */
- case HELO_CMD:
- hello = US"HELO";
- esmtp = FALSE;
- goto HELO_EHLO;
+ /* The DATA command is legal only if it follows successful MAIL FROM
+ and RCPT TO commands. However, if pipelining is advertised, a bad DATA is
+ not counted as a protocol error if it follows RCPT (which must have been
+ rejected if there are no recipients.) This function is complete when a
+ valid DATA command is encountered.
- case EHLO_CMD:
- hello = US"EHLO";
- esmtp = TRUE;
+ Note concerning the code used: RFC 2821 says this:
- HELO_EHLO: /* Common code for HELO and EHLO */
- cmd_list[CMD_LIST_HELO].is_mail_cmd = FALSE;
- cmd_list[CMD_LIST_EHLO].is_mail_cmd = FALSE;
+ - If there was no MAIL, or no RCPT, command, or all such commands
+ were rejected, the server MAY return a "command out of sequence"
+ (503) or "no valid recipients" (554) reply in response to the
+ DATA command.
- /* Reject the HELO if its argument was invalid or non-existent. A
- successful check causes the argument to be saved in malloc store. */
+ The example in the pipelining RFC 2920 uses 554, but I use 503 here
+ because it is the same whether pipelining is in use or not.
+
+ If all the RCPT commands that precede DATA provoked the same error message
+ (often indicating some kind of system error), it is helpful to include it
+ with the DATA rejection (an idea suggested by Tony Finch). */
- if (!check_helo(smtp_command_argument))
+ case BDAT_CMD:
{
- smtp_printf("501 Syntactically invalid %s argument(s)\r\n", hello);
+ int n;
+
+ HAD(SCH_BDAT);
+ if (chunking_state != CHUNKING_OFFERED)
+ {
+ done = synprot_error(L_smtp_protocol_error, 503, NULL,
+ US"BDAT command used when CHUNKING not advertised");
+ break;
+ }
+
+ /* grab size, endmarker */
+
+ if (sscanf(CS smtp_cmd_data, "%u %n", &chunking_datasize, &n) < 1)
+ {
+ done = synprot_error(L_smtp_protocol_error, 501, NULL,
+ US"missing size for BDAT command");
+ break;
+ }
+ chunking_state = strcmpic(smtp_cmd_data+n, US"LAST") == 0
+ ? CHUNKING_LAST : CHUNKING_ACTIVE;
+ chunking_data_left = chunking_datasize;
+ DEBUG(D_receive) debug_printf("chunking state %d, %d bytes\n",
+ (int)chunking_state, chunking_data_left);
+
+ /* push the current receive_* function on the "stack", and
+ replace them by bdat_getc(), which in turn will use the lwr_receive_*
+ functions to do the dirty work. */
+ lwr_receive_getc = receive_getc;
+ lwr_receive_getbuf = receive_getbuf;
+ lwr_receive_ungetc = receive_ungetc;
+
+ receive_getc = bdat_getc;
+ receive_ungetc = bdat_ungetc;
+
+ f.dot_ends = FALSE;
+
+ goto DATA_BDAT;
+ }
- log_write(0, LOG_MAIN|LOG_REJECT, "rejected %s from %s: syntactically "
- "invalid argument(s): %s", hello, host_and_ident(FALSE),
- (*smtp_command_argument == 0)? US"(no argument given)" :
- string_printing(smtp_command_argument));
+ case DATA_CMD:
+ HAD(SCH_DATA);
+ f.dot_ends = TRUE;
- if (++synprot_error_count > smtp_max_synprot_errors)
- {
- log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many "
- "syntax or protocol errors (last command was \"%s\")",
- host_and_ident(FALSE), cmd_buffer);
- done = 1;
- }
+ DATA_BDAT: /* Common code for DATA and BDAT */
+#ifdef SUPPORT_PIPE_CONNECT
+ fl.pipe_connect_acceptable = FALSE;
+#endif
+ if (!discarded && recipients_count <= 0)
+ {
+ if (fl.rcpt_smtp_response_same && rcpt_smtp_response != NULL)
+ {
+ uschar *code = US"503";
+ int len = Ustrlen(rcpt_smtp_response);
+ smtp_respond(code, 3, FALSE, US"All RCPT commands were rejected with "
+ "this error:");
+ /* Responses from smtp_printf() will have \r\n on the end */
+ if (len > 2 && rcpt_smtp_response[len-2] == '\r')
+ rcpt_smtp_response[len-2] = 0;
+ smtp_respond(code, 3, FALSE, rcpt_smtp_response);
+ }
+ if (f.smtp_in_pipelining_advertised && last_was_rcpt)
+ smtp_printf("503 Valid RCPT command must precede %s\r\n", FALSE,
+ smtp_names[smtp_connection_had[smtp_ch_index-1]]);
+ else
+ done = synprot_error(L_smtp_protocol_error, 503, NULL,
+ smtp_connection_had[smtp_ch_index-1] == SCH_DATA
+ ? US"valid RCPT command must precede DATA"
+ : US"valid RCPT command must precede BDAT");
+
+ if (chunking_state > CHUNKING_OFFERED)
+ bdat_flush_data();
+ break;
+ }
+
+ if (toomany && recipients_max_reject)
+ {
+ sender_address = NULL; /* This will allow a new MAIL without RSET */
+ sender_address_unrewritten = NULL;
+ smtp_printf("554 Too many recipients\r\n", FALSE);
+ break;
+ }
+
+ if (chunking_state > CHUNKING_OFFERED)
+ rc = OK; /* No predata ACL or go-ahead output for BDAT */
+ else
+ {
+ /* If there is an ACL, re-check the synchronization afterwards, since the
+ ACL may have delayed. To handle cutthrough delivery enforce a dummy call
+ to get the DATA command sent. */
+
+ if (acl_smtp_predata == NULL && cutthrough.cctx.sock < 0)
+ rc = OK;
+ else
+ {
+ uschar * acl = acl_smtp_predata ? acl_smtp_predata : US"accept";
+ f.enable_dollar_recipients = TRUE;
+ rc = acl_check(ACL_WHERE_PREDATA, NULL, acl, &user_msg,
+ &log_msg);
+ f.enable_dollar_recipients = FALSE;
+ if (rc == OK && !check_sync())
+ goto SYNC_FAILURE;
+
+ if (rc != OK)
+ { /* Either the ACL failed the address, or it was deferred. */
+ done = smtp_handle_acl_fail(ACL_WHERE_PREDATA, rc, user_msg, log_msg);
+ break;
+ }
+ }
+
+ if (user_msg)
+ smtp_user_msg(US"354", user_msg);
+ else
+ smtp_printf(
+ "354 Enter message, ending with \".\" on a line by itself\r\n", FALSE);
+ }
+
+#ifdef TCP_QUICKACK
+ if (smtp_in) /* all ACKs needed to ramp window up for bulk data */
+ (void) setsockopt(fileno(smtp_in), IPPROTO_TCP, TCP_QUICKACK,
+ US &on, sizeof(on));
+#endif
+ done = 3;
+ message_ended = END_NOTENDED; /* Indicate in middle of data */
break;
- }
- /* If sender_host_unknown is true, we have got here via the -bs interface,
- not called from inetd. Otherwise, we are running an IP connection and the
- host address will be set. If the helo name is the primary name of this
- host and we haven't done a reverse lookup, force one now. If helo_required
- is set, ensure that the HELO name matches the actual host. If helo_verify
- is set, do the same check, but softly. */
- if (!sender_host_unknown)
+ case VRFY_CMD:
{
- BOOL old_helo_verified = helo_verified;
- uschar *p = smtp_command_argument;
-
- while (*p != 0 && !isspace(*p)) { *p = tolower(*p); p++; }
- *p = 0;
-
- /* Force a reverse lookup if HELO quoted something in helo_lookup_domains
- because otherwise the log can be confusing. */
+ uschar * address;
- if (sender_host_name == NULL &&
- (deliver_domain = sender_helo_name, /* set $domain */
- match_isinlist(sender_helo_name, &helo_lookup_domains, 0,
- &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL)) == OK)
- (void)host_name_lookup();
+ HAD(SCH_VRFY);
- /* Rebuild the fullhost info to include the HELO name (and the real name
- if it was looked up.) */
+ if (!(address = parse_extract_address(smtp_cmd_data, &errmess,
+ &start, &end, &recipient_domain, FALSE)))
+ {
+ smtp_printf("501 %s\r\n", FALSE, errmess);
+ break;
+ }
- host_build_sender_fullhost(); /* Rebuild */
- set_process_info("handling%s incoming connection from %s",
- (tls_active >= 0)? " TLS" : "", host_and_ident(FALSE));
+ if (!recipient_domain)
+ if (!(recipient_domain = qualify_recipient(&address, smtp_cmd_data,
+ US"verify")))
+ break;
- /* Verify if configured. This doesn't give much security, but it does
- make some people happy to be able to do it. If helo_required is set,
- (host matches helo_verify_hosts) failure forces rejection. If helo_verify
- is set (host matches helo_try_verify_hosts), it does not. This is perhaps
- now obsolescent, since the verification can now be requested selectively
- at ACL time. */
-
- helo_verified = helo_verify_failed = FALSE;
- if (helo_required || helo_verify)
- {
- BOOL tempfail = !smtp_verify_helo();
- if (!helo_verified)
- {
- if (helo_required)
- {
- smtp_printf("%d %s argument does not match calling host\r\n",
- tempfail? 451 : 550, hello);
- log_write(0, LOG_MAIN|LOG_REJECT, "%srejected \"%s %s\" from %s",
- tempfail? "temporarily " : "",
- hello, sender_helo_name, host_and_ident(FALSE));
- helo_verified = old_helo_verified;
- break; /* End of HELO/EHLO processing */
- }
- HDEBUG(D_all) debug_printf("%s verification failed but host is in "
- "helo_try_verify_hosts\n", hello);
- }
- }
+ if ((rc = acl_check(ACL_WHERE_VRFY, address, acl_smtp_vrfy,
+ &user_msg, &log_msg)) != OK)
+ done = smtp_handle_acl_fail(ACL_WHERE_VRFY, rc, user_msg, log_msg);
+ else
+ {
+ uschar * s = NULL;
+ address_item * addr = deliver_make_addr(address, FALSE);
+
+ switch(verify_address(addr, NULL, vopt_is_recipient | vopt_qualify, -1,
+ -1, -1, NULL, NULL, NULL))
+ {
+ case OK:
+ s = string_sprintf("250 <%s> is deliverable", address);
+ break;
+
+ case DEFER:
+ s = (addr->user_message != NULL)?
+ string_sprintf("451 <%s> %s", address, addr->user_message) :
+ string_sprintf("451 Cannot resolve <%s> at this time", address);
+ break;
+
+ case FAIL:
+ s = (addr->user_message != NULL)?
+ string_sprintf("550 <%s> %s", address, addr->user_message) :
+ string_sprintf("550 <%s> is not deliverable", address);
+ log_write(0, LOG_MAIN, "VRFY failed for %s %s",
+ smtp_cmd_argument, host_and_ident(TRUE));
+ break;
+ }
+
+ smtp_printf("%s\r\n", FALSE, s);
+ }
+ break;
}
-#ifdef EXPERIMENTAL_SPF
- /* set up SPF context */
- spf_init(sender_helo_name, sender_host_address);
-#endif
-
- /* Apply an ACL check if one is defined */
- if (acl_smtp_helo != NULL)
- {
- rc = acl_check(ACL_WHERE_HELO, NULL, acl_smtp_helo, &user_msg, &log_msg);
+ case EXPN_CMD:
+ HAD(SCH_EXPN);
+ rc = acl_check(ACL_WHERE_EXPN, NULL, acl_smtp_expn, &user_msg, &log_msg);
if (rc != OK)
- {
- done = smtp_handle_acl_fail(ACL_WHERE_HELO, rc, user_msg, log_msg);
- sender_helo_name = NULL;
- host_build_sender_fullhost(); /* Rebuild */
- break;
- }
- }
+ done = smtp_handle_acl_fail(ACL_WHERE_EXPN, rc, user_msg, log_msg);
+ else
+ {
+ BOOL save_log_testing_mode = f.log_testing_mode;
+ f.address_test_mode = f.log_testing_mode = TRUE;
+ (void) verify_address(deliver_make_addr(smtp_cmd_data, FALSE),
+ smtp_out, vopt_is_recipient | vopt_qualify | vopt_expn, -1, -1, -1,
+ NULL, NULL, NULL);
+ f.address_test_mode = FALSE;
+ f.log_testing_mode = save_log_testing_mode; /* true for -bh */
+ }
+ break;
- /* The EHLO/HELO command is acceptable. Reset the protocol and the state,
- abandoning any previous message. */
-
- received_protocol = (esmtp?
- protocols[pextend +
- ((sender_host_authenticated != NULL)? pauthed : 0) +
- ((tls_active >= 0)? pcrpted : 0)]
- :
- protocols[pnormal + ((tls_active >= 0)? pcrpted : 0)])
- +
- ((sender_host_address != NULL)? pnlocal : 0);
-
- smtp_reset(reset_point);
- toomany = FALSE;
-
- /* Generate an OK reply, including the ident if present, and also
- the IP address if present. Reflecting back the ident is intended
- as a deterrent to mail forgers. For maximum efficiency, and also
- because some broken systems expect each response to be in a single
- packet, arrange that it is sent in one write(). */
-
- auth_advertised = FALSE;
- pipelining_advertised = FALSE;
- #ifdef SUPPORT_TLS
- tls_advertised = FALSE;
- #endif
- s = string_sprintf("250 %s Hello %s%s%s",
- smtp_active_hostname,
- (sender_ident == NULL)? US"" : sender_ident,
- (sender_ident == NULL)? US"" : US" at ",
- (sender_host_name == NULL)? sender_helo_name : sender_host_name);
+ #ifndef DISABLE_TLS
- ptr = Ustrlen(s);
- size = ptr + 1;
+ case STARTTLS_CMD:
+ HAD(SCH_STARTTLS);
+ if (!fl.tls_advertised)
+ {
+ done = synprot_error(L_smtp_protocol_error, 503, NULL,
+ US"STARTTLS command used when not advertised");
+ break;
+ }
+
+ /* Apply an ACL check if one is defined */
+
+ if ( acl_smtp_starttls
+ && (rc = acl_check(ACL_WHERE_STARTTLS, NULL, acl_smtp_starttls,
+ &user_msg, &log_msg)) != OK
+ )
+ {
+ done = smtp_handle_acl_fail(ACL_WHERE_STARTTLS, rc, user_msg, log_msg);
+ break;
+ }
+
+ /* RFC 2487 is not clear on when this command may be sent, though it
+ does state that all information previously obtained from the client
+ must be discarded if a TLS session is started. It seems reasonable to
+ do an implied RSET when STARTTLS is received. */
+
+ incomplete_transaction_log(US"STARTTLS");
+ cancel_cutthrough_connection(TRUE, US"STARTTLS received");
+ reset_point = smtp_reset(reset_point);
+ toomany = FALSE;
+ cmd_list[CMD_LIST_STARTTLS].is_mail_cmd = FALSE;
+
+ /* There's an attack where more data is read in past the STARTTLS command
+ before TLS is negotiated, then assumed to be part of the secure session
+ when used afterwards; we use segregated input buffers, so are not
+ vulnerable, but we want to note when it happens and, for sheer paranoia,
+ ensure that the buffer is "wiped".
+ Pipelining sync checks will normally have protected us too, unless disabled
+ by configuration. */
+
+ if (receive_smtp_buffered())
+ {
+ DEBUG(D_any)
+ debug_printf("Non-empty input buffer after STARTTLS; naive attack?\n");
+ if (tls_in.active.sock < 0)
+ smtp_inend = smtp_inptr = smtp_inbuffer;
+ /* and if TLS is already active, tls_server_start() should fail */
+ }
+
+ /* There is nothing we value in the input buffer and if TLS is successfully
+ negotiated, we won't use this buffer again; if TLS fails, we'll just read
+ fresh content into it. The buffer contains arbitrary content from an
+ untrusted remote source; eg: NOOP <shellcode>\r\nSTARTTLS\r\n
+ It seems safest to just wipe away the content rather than leave it as a
+ target to jump to. */
+
+ memset(smtp_inbuffer, 0, IN_BUFFER_SIZE);
+
+ /* Attempt to start up a TLS session, and if successful, discard all
+ knowledge that was obtained previously. At least, that's what the RFC says,
+ and that's what happens by default. However, in order to work round YAEB,
+ there is an option to remember the esmtp state. Sigh.
+
+ We must allow for an extra EHLO command and an extra AUTH command after
+ STARTTLS that don't add to the nonmail command count. */
+
+ s = NULL;
+ if ((rc = tls_server_start(tls_require_ciphers, &s)) == OK)
+ {
+ if (!tls_remember_esmtp)
+ fl.helo_seen = fl.esmtp = fl.auth_advertised = f.smtp_in_pipelining_advertised = FALSE;
+ cmd_list[CMD_LIST_EHLO].is_mail_cmd = TRUE;
+ cmd_list[CMD_LIST_AUTH].is_mail_cmd = TRUE;
+ cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd = TRUE;
+ if (sender_helo_name)
+ {
+ sender_helo_name = NULL;
+ host_build_sender_fullhost(); /* Rebuild */
+ set_process_info("handling incoming TLS connection from %s",
+ host_and_ident(FALSE));
+ }
+ received_protocol =
+ (sender_host_address ? protocols : protocols_local)
+ [ (fl.esmtp
+ ? pextend + (sender_host_authenticated ? pauthed : 0)
+ : pnormal)
+ + (tls_in.active.sock >= 0 ? pcrpted : 0)
+ ];
+
+ sender_host_auth_pubname = sender_host_authenticated = NULL;
+ authenticated_id = NULL;
+ sync_cmd_limit = NON_SYNC_CMD_NON_PIPELINING;
+ DEBUG(D_tls) debug_printf("TLS active\n");
+ break; /* Successful STARTTLS */
+ }
+ else
+ (void) smtp_log_tls_fail(s);
+
+ /* Some local configuration problem was discovered before actually trying
+ to do a TLS handshake; give a temporary error. */
+
+ if (rc == DEFER)
+ {
+ smtp_printf("454 TLS currently unavailable\r\n", FALSE);
+ break;
+ }
+
+ /* Hard failure. Reject everything except QUIT or closed connection. One
+ cause for failure is a nested STARTTLS, in which case tls_in.active remains
+ set, but we must still reject all incoming commands. Another is a handshake
+ failure - and there may some encrypted data still in the pipe to us, which we
+ see as garbage commands. */
+
+ DEBUG(D_tls) debug_printf("TLS failed to start\n");
+ while (done <= 0) switch(smtp_read_command(FALSE, GETC_BUFFER_UNLIMITED))
+ {
+ case EOF_CMD:
+ log_write(L_smtp_connection, LOG_MAIN, "%s closed by EOF",
+ smtp_get_connection_info());
+ smtp_notquit_exit(US"tls-failed", NULL, NULL);
+ done = 2;
+ break;
+
+ /* It is perhaps arguable as to which exit ACL should be called here,
+ but as it is probably a situation that almost never arises, it
+ probably doesn't matter. We choose to call the real QUIT ACL, which in
+ some sense is perhaps "right". */
+
+ case QUIT_CMD:
+ user_msg = NULL;
+ if ( acl_smtp_quit
+ && ((rc = acl_check(ACL_WHERE_QUIT, NULL, acl_smtp_quit, &user_msg,
+ &log_msg)) == ERROR))
+ log_write(0, LOG_MAIN|LOG_PANIC, "ACL for QUIT returned ERROR: %s",
+ log_msg);
+ if (user_msg)
+ smtp_respond(US"221", 3, TRUE, user_msg);
+ else
+ smtp_printf("221 %s closing connection\r\n", FALSE, smtp_active_hostname);
+ log_write(L_smtp_connection, LOG_MAIN, "%s closed by QUIT",
+ smtp_get_connection_info());
+ done = 2;
+ break;
+
+ default:
+ smtp_printf("554 Security failure\r\n", FALSE);
+ break;
+ }
+ tls_close(NULL, TLS_SHUTDOWN_NOWAIT);
+ break;
+ #endif
- if (sender_host_address != NULL)
- {
- s = string_cat(s, &size, &ptr, US" [", 2);
- s = string_cat(s, &size, &ptr, sender_host_address,
- Ustrlen(sender_host_address));
- s = string_cat(s, &size, &ptr, US"]", 1);
- }
- s = string_cat(s, &size, &ptr, US"\r\n", 2);
+ /* The ACL for QUIT is provided for gathering statistical information or
+ similar; it does not affect the response code, but it can supply a custom
+ message. */
- /* If we received EHLO, we must create a multiline response which includes
- the functions supported. */
+ case QUIT_CMD:
+ smtp_quit_handler(&user_msg, &log_msg);
+ done = 2;
+ break;
- if (esmtp)
- {
- s[3] = '-';
- /* I'm not entirely happy with this, as an MTA is supposed to check
- that it has enough room to accept a message of maximum size before
- it sends this. However, there seems little point in not sending it.
- The actual size check happens later at MAIL FROM time. By postponing it
- till then, VRFY and EXPN can be used after EHLO when space is short. */
+ case RSET_CMD:
+ smtp_rset_handler();
+ cancel_cutthrough_connection(TRUE, US"RSET received");
+ reset_point = smtp_reset(reset_point);
+ toomany = FALSE;
+ break;
- if (thismessage_size_limit > 0)
- {
- sprintf(CS big_buffer, "250-SIZE %d\r\n", thismessage_size_limit);
- s = string_cat(s, &size, &ptr, big_buffer, Ustrlen(big_buffer));
- }
- else
- {
- s = string_cat(s, &size, &ptr, US"250-SIZE\r\n", 10);
- }
- /* Exim does not do protocol conversion or data conversion. It is 8-bit
- clean; if it has an 8-bit character in its hand, it just sends it. It
- cannot therefore specify 8BITMIME and remain consistent with the RFCs.
- However, some users want this option simply in order to stop MUAs
- mangling messages that contain top-bit-set characters. It is therefore
- provided as an option. */
+ case NOOP_CMD:
+ HAD(SCH_NOOP);
+ smtp_printf("250 OK\r\n", FALSE);
+ break;
- if (accept_8bitmime)
- s = string_cat(s, &size, &ptr, US"250-8BITMIME\r\n", 14);
- /* Advertise ETRN if there's an ACL checking whether a host is
- permitted to issue it; a check is made when any host actually tries. */
+ /* Show ETRN/EXPN/VRFY if there's an ACL for checking hosts; if actually
+ used, a check will be done for permitted hosts. Show STARTTLS only if not
+ already in a TLS session and if it would be advertised in the EHLO
+ response. */
- if (acl_smtp_etrn != NULL)
- {
- s = string_cat(s, &size, &ptr, US"250-ETRN\r\n", 10);
- }
+ case HELP_CMD:
+ HAD(SCH_HELP);
+ smtp_printf("214-Commands supported:\r\n", TRUE);
+ {
+ uschar buffer[256];
+ buffer[0] = 0;
+ Ustrcat(buffer, US" AUTH");
+ #ifndef DISABLE_TLS
+ if (tls_in.active.sock < 0 &&
+ verify_check_host(&tls_advertise_hosts) != FAIL)
+ Ustrcat(buffer, US" STARTTLS");
+ #endif
+ Ustrcat(buffer, US" HELO EHLO MAIL RCPT DATA BDAT");
+ Ustrcat(buffer, US" NOOP QUIT RSET HELP");
+ if (acl_smtp_etrn) Ustrcat(buffer, US" ETRN");
+ if (acl_smtp_expn) Ustrcat(buffer, US" EXPN");
+ if (acl_smtp_vrfy) Ustrcat(buffer, US" VRFY");
+ smtp_printf("214%s\r\n", FALSE, buffer);
+ }
+ break;
- /* Advertise EXPN if there's an ACL checking whether a host is
- permitted to issue it; a check is made when any host actually tries. */
- if (acl_smtp_expn != NULL)
- {
- s = string_cat(s, &size, &ptr, US"250-EXPN\r\n", 10);
- }
-
- /* Exim is quite happy with pipelining, so let the other end know that
- it is safe to use it, unless advertising is disabled. */
-
- if (verify_check_host(&pipelining_advertise_hosts) == OK)
- {
- s = string_cat(s, &size, &ptr, US"250-PIPELINING\r\n", 16);
- sync_cmd_limit = NON_SYNC_CMD_PIPELINING;
- pipelining_advertised = TRUE;
- }
-
- /* If any server authentication mechanisms are configured, advertise
- them if the current host is in auth_advertise_hosts. The problem with
- advertising always is that some clients then require users to
- authenticate (and aren't configurable otherwise) even though it may not
- be necessary (e.g. if the host is in host_accept_relay).
-
- RFC 2222 states that SASL mechanism names contain only upper case
- letters, so output the names in upper case, though we actually recognize
- them in either case in the AUTH command. */
-
- if (auths != NULL)
- {
- if (verify_check_host(&auth_advertise_hosts) == OK)
- {
- auth_instance *au;
- BOOL first = TRUE;
- for (au = auths; au != NULL; au = au->next)
- {
- if (au->server && (au->advertise_condition == NULL ||
- expand_check_condition(au->advertise_condition, au->name,
- US"authenticator")))
- {
- int saveptr;
- if (first)
- {
- s = string_cat(s, &size, &ptr, US"250-AUTH", 8);
- first = FALSE;
- auth_advertised = TRUE;
- }
- saveptr = ptr;
- s = string_cat(s, &size, &ptr, US" ", 1);
- s = string_cat(s, &size, &ptr, au->public_name,
- Ustrlen(au->public_name));
- while (++saveptr < ptr) s[saveptr] = toupper(s[saveptr]);
- au->advertised = TRUE;
- }
- else au->advertised = FALSE;
- }
- if (!first) s = string_cat(s, &size, &ptr, US"\r\n", 2);
- }
- }
-
- /* Advertise TLS (Transport Level Security) aka SSL (Secure Socket Layer)
- if it has been included in the binary, and the host matches
- tls_advertise_hosts. We must *not* advertise if we are already in a
- secure connection. */
-
- #ifdef SUPPORT_TLS
- if (tls_active < 0 &&
- verify_check_host(&tls_advertise_hosts) != FAIL)
- {
- s = string_cat(s, &size, &ptr, US"250-STARTTLS\r\n", 14);
- tls_advertised = TRUE;
- }
- #endif
-
- /* Finish off the multiline reply with one that is always available. */
-
- s = string_cat(s, &size, &ptr, US"250 HELP\r\n", 10);
- }
-
- /* Terminate the string (for debug), write it, and note that HELO/EHLO
- has been seen. */
-
- s[ptr] = 0;
-
- #ifdef SUPPORT_TLS
- if (tls_active >= 0) (void)tls_write(s, ptr); else
- #endif
-
- (void)fwrite(s, 1, ptr, smtp_out);
- DEBUG(D_receive) debug_printf("SMTP>> %s", s);
- helo_seen = TRUE;
- break; /* HELO/EHLO */
-
-
- /* The MAIL command requires an address as an operand. All we do
- here is to parse it for syntactic correctness. The form "<>" is
- a special case which converts into an empty string. The start/end
- pointers in the original are not used further for this address, as
- it is the canonical extracted address which is all that is kept. */
-
- case MAIL_CMD:
- smtp_mailcmd_count++; /* Count for limit and ratelimit */
- was_rej_mail = TRUE; /* Reset if accepted */
-
- if (helo_required && !helo_seen)
- {
- smtp_printf("503 HELO or EHLO required\r\n");
- log_write(0, LOG_MAIN|LOG_REJECT, "rejected MAIL from %s: no "
- "HELO/EHLO given", host_and_ident(FALSE));
- break;
- }
-
- if (sender_address != NULL)
- {
- done = synprot_error(L_smtp_protocol_error, 503, NULL,
- US"sender already given");
- break;
- }
-
- if (smtp_command_argument[0] == 0)
- {
- done = synprot_error(L_smtp_protocol_error, 501, NULL,
- US"MAIL must have an address operand");
- break;
- }
-
- /* Check to see if the limit for messages per connection would be
- exceeded by accepting further messages. */
-
- if (smtp_accept_max_per_connection > 0 &&
- smtp_mailcmd_count > smtp_accept_max_per_connection)
- {
- smtp_printf("421 too many messages in this connection\r\n");
- log_write(0, LOG_MAIN|LOG_REJECT, "rejected MAIL command %s: too many "
- "messages in one connection", host_and_ident(TRUE));
- break;
- }
-
- /* Reset for start of message - even if this is going to fail, we
- obviously need to throw away any previous data. */
-
- smtp_reset(reset_point);
- toomany = FALSE;
- sender_data = recipient_data = NULL;
-
- /* Loop, checking for ESMTP additions to the MAIL FROM command. */
-
- if (esmtp) for(;;)
- {
- uschar *name, *value, *end;
- unsigned long int size;
-
- if (!extract_option(&name, &value)) break;
-
- /* Handle SIZE= by reading the value. We don't do the check till later,
- in order to be able to log the sender address on failure. */
-
- if (strcmpic(name, US"SIZE") == 0 &&
- ((size = (int)Ustrtoul(value, &end, 10)), *end == 0))
- {
- if ((size == ULONG_MAX && errno == ERANGE) || size > INT_MAX)
- size = INT_MAX;
- message_size = (int)size;
- }
-
- /* If this session was initiated with EHLO and accept_8bitmime is set,
- Exim will have indicated that it supports the BODY=8BITMIME option. In
- fact, it does not support this according to the RFCs, in that it does not
- take any special action for forwarding messages containing 8-bit
- characters. That is why accept_8bitmime is not the default setting, but
- some sites want the action that is provided. We recognize both "8BITMIME"
- and "7BIT" as body types, but take no action. */
-
- else if (accept_8bitmime && strcmpic(name, US"BODY") == 0 &&
- (strcmpic(value, US"8BITMIME") == 0 ||
- strcmpic(value, US"7BIT") == 0)) {}
-
- /* Handle the AUTH extension. If the value given is not "<>" and either
- the ACL says "yes" or there is no ACL but the sending host is
- authenticated, we set it up as the authenticated sender. However, if the
- authenticator set a condition to be tested, we ignore AUTH on MAIL unless
- the condition is met. The value of AUTH is an xtext, which means that +,
- = and cntrl chars are coded in hex; however "<>" is unaffected by this
- coding. */
-
- else if (strcmpic(name, US"AUTH") == 0)
- {
- if (Ustrcmp(value, "<>") != 0)
- {
- int rc;
- uschar *ignore_msg;
-
- if (auth_xtextdecode(value, &authenticated_sender) < 0)
- {
- /* Put back terminator overrides for error message */
- name[-1] = ' ';
- value[-1] = '=';
- done = synprot_error(L_smtp_syntax_error, 501, NULL,
- US"invalid data for AUTH");
- goto COMMAND_LOOP;
- }
-
- if (acl_smtp_mailauth == NULL)
- {
- ignore_msg = US"client not authenticated";
- rc = (sender_host_authenticated != NULL)? OK : FAIL;
- }
- else
- {
- ignore_msg = US"rejected by ACL";
- rc = acl_check(ACL_WHERE_MAILAUTH, NULL, acl_smtp_mailauth,
- &user_msg, &log_msg);
- }
-
- switch (rc)
- {
- case OK:
- if (authenticated_by == NULL ||
- authenticated_by->mail_auth_condition == NULL ||
- expand_check_condition(authenticated_by->mail_auth_condition,
- authenticated_by->name, US"authenticator"))
- break; /* Accept the AUTH */
-
- ignore_msg = US"server_mail_auth_condition failed";
- if (authenticated_id != NULL)
- ignore_msg = string_sprintf("%s: authenticated ID=\"%s\"",
- ignore_msg, authenticated_id);
-
- /* Fall through */
-
- case FAIL:
- authenticated_sender = NULL;
- log_write(0, LOG_MAIN, "ignoring AUTH=%s from %s (%s)",
- value, host_and_ident(TRUE), ignore_msg);
- break;
-
- /* Should only get DEFER or ERROR here. Put back terminator
- overrides for error message */
-
- default:
- name[-1] = ' ';
- value[-1] = '=';
- (void)smtp_handle_acl_fail(ACL_WHERE_MAILAUTH, rc, user_msg,
- log_msg);
- goto COMMAND_LOOP;
- }
- }
- }
-
- /* Unknown option. Stick back the terminator characters and break
- the loop. An error for a malformed address will occur. */
+ case EOF_CMD:
+ incomplete_transaction_log(US"connection lost");
+ smtp_notquit_exit(US"connection-lost", US"421",
+ US"%s lost input connection", smtp_active_hostname);
+
+ /* Don't log by default unless in the middle of a message, as some mailers
+ just drop the call rather than sending QUIT, and it clutters up the logs.
+ */
+
+ if (sender_address || recipients_count > 0)
+ log_write(L_lost_incoming_connection, LOG_MAIN,
+ "unexpected %s while reading SMTP command from %s%s%s D=%s",
+ f.sender_host_unknown ? "EOF" : "disconnection",
+ f.tcp_in_fastopen_logged
+ ? US""
+ : f.tcp_in_fastopen
+ ? f.tcp_in_fastopen_data ? US"TFO* " : US"TFO "
+ : US"",
+ host_and_ident(FALSE), smtp_read_error,
+ string_timesince(&smtp_connection_start)
+ );
else
- {
- name[-1] = ' ';
- value[-1] = '=';
- break;
- }
- }
-
- /* If we have passed the threshold for rate limiting, apply the current
- delay, and update it for next time, provided this is a limited host. */
-
- if (smtp_mailcmd_count > smtp_rlm_threshold &&
- verify_check_host(&smtp_ratelimit_hosts) == OK)
- {
- DEBUG(D_receive) debug_printf("rate limit MAIL: delay %.3g sec\n",
- smtp_delay_mail/1000.0);
- millisleep((int)smtp_delay_mail);
- smtp_delay_mail *= smtp_rlm_factor;
- if (smtp_delay_mail > (double)smtp_rlm_limit)
- smtp_delay_mail = (double)smtp_rlm_limit;
- }
-
- /* Now extract the address, first applying any SMTP-time rewriting. The
- TRUE flag allows "<>" as a sender address. */
-
- raw_sender = ((rewrite_existflags & rewrite_smtp) != 0)?
- rewrite_one(smtp_command_argument, rewrite_smtp, NULL, FALSE, US"",
- global_rewrite_rules) : smtp_command_argument;
-
- /* rfc821_domains = TRUE; << no longer needed */
- raw_sender =
- parse_extract_address(raw_sender, &errmess, &start, &end, &sender_domain,
- TRUE);
- /* rfc821_domains = FALSE; << no longer needed */
-
- if (raw_sender == NULL)
- {
- done = synprot_error(L_smtp_syntax_error, 501, smtp_command_argument, errmess);
+ log_write(L_smtp_connection, LOG_MAIN, "%s %slost%s D=%s",
+ smtp_get_connection_info(),
+ f.tcp_in_fastopen && !f.tcp_in_fastopen_logged ? US"TFO " : US"",
+ smtp_read_error,
+ string_timesince(&smtp_connection_start)
+ );
+
+ done = 1;
break;
- }
-
- sender_address = raw_sender;
- /* If there is a configured size limit for mail, check that this message
- doesn't exceed it. The check is postponed to this point so that the sender
- can be logged. */
- if (thismessage_size_limit > 0 && message_size > thismessage_size_limit)
- {
- smtp_printf("552 Message size exceeds maximum permitted\r\n");
- log_write(L_size_reject,
- LOG_MAIN|LOG_REJECT, "rejected MAIL FROM:<%s> %s: "
- "message too big: size%s=%d max=%d",
- sender_address,
- host_and_ident(TRUE),
- (message_size == INT_MAX)? ">" : "",
- message_size,
- thismessage_size_limit);
- sender_address = NULL;
- break;
- }
-
- /* Check there is enough space on the disk unless configured not to.
- When smtp_check_spool_space is set, the check is for thismessage_size_limit
- plus the current message - i.e. we accept the message only if it won't
- reduce the space below the threshold. Add 5000 to the size to allow for
- overheads such as the Received: line and storing of recipients, etc.
- By putting the check here, even when SIZE is not given, it allow VRFY
- and EXPN etc. to be used when space is short. */
-
- if (!receive_check_fs(
- (smtp_check_spool_space && message_size >= 0)?
- message_size + 5000 : 0))
- {
- smtp_printf("452 Space shortage, please try later\r\n");
- sender_address = NULL;
- break;
- }
-
- /* If sender_address is unqualified, reject it, unless this is a locally
- generated message, or the sending host or net is permitted to send
- unqualified addresses - typically local machines behaving as MUAs -
- in which case just qualify the address. The flag is set above at the start
- of the SMTP connection. */
+ case ETRN_CMD:
+ HAD(SCH_ETRN);
+ if (sender_address)
+ {
+ done = synprot_error(L_smtp_protocol_error, 503, NULL,
+ US"ETRN is not permitted inside a transaction");
+ break;
+ }
+
+ log_write(L_etrn, LOG_MAIN, "ETRN %s received from %s", smtp_cmd_argument,
+ host_and_ident(FALSE));
+
+ if ((rc = acl_check(ACL_WHERE_ETRN, NULL, acl_smtp_etrn,
+ &user_msg, &log_msg)) != OK)
+ {
+ done = smtp_handle_acl_fail(ACL_WHERE_ETRN, rc, user_msg, log_msg);
+ break;
+ }
+
+ /* Compute the serialization key for this command. */
+
+ etrn_serialize_key = string_sprintf("etrn-%s\n", smtp_cmd_data);
+
+ /* If a command has been specified for running as a result of ETRN, we
+ permit any argument to ETRN. If not, only the # standard form is permitted,
+ since that is strictly the only kind of ETRN that can be implemented
+ according to the RFC. */
+
+ if (smtp_etrn_command)
+ {
+ uschar *error;
+ BOOL rc;
+ etrn_command = smtp_etrn_command;
+ deliver_domain = smtp_cmd_data;
+ rc = transport_set_up_command(&argv, smtp_etrn_command, TRUE, 0, NULL,
+ US"ETRN processing", &error);
+ deliver_domain = NULL;
+ if (!rc)
+ {
+ log_write(0, LOG_MAIN|LOG_PANIC, "failed to set up ETRN command: %s",
+ error);
+ smtp_printf("458 Internal failure\r\n", FALSE);
+ break;
+ }
+ }
+
+ /* Else set up to call Exim with the -R option. */
- if (sender_domain == 0 && sender_address[0] != 0)
- {
- if (allow_unqualified_sender)
- {
- sender_domain = Ustrlen(sender_address) + 1;
- sender_address = rewrite_address_qualify(sender_address, FALSE);
- DEBUG(D_receive) debug_printf("unqualified address %s accepted\n",
- raw_sender);
- }
else
- {
- smtp_printf("501 %s: sender address must contain a domain\r\n",
- smtp_command_argument);
- log_write(L_smtp_syntax_error,
- LOG_MAIN|LOG_REJECT,
- "unqualified sender rejected: <%s> %s%s",
- raw_sender,
- host_and_ident(TRUE),
- host_lookup_msg);
- sender_address = NULL;
- break;
- }
- }
-
- /* Apply an ACL check if one is defined, before responding */
-
- rc = (acl_smtp_mail == NULL)? OK :
- acl_check(ACL_WHERE_MAIL, NULL, acl_smtp_mail, &user_msg, &log_msg);
-
- if (rc == OK || rc == DISCARD)
- {
- smtp_printf("250 OK\r\n");
- smtp_delay_rcpt = smtp_rlr_base;
- recipients_discarded = (rc == DISCARD);
- was_rej_mail = FALSE;
- }
-
- else
- {
- done = smtp_handle_acl_fail(ACL_WHERE_MAIL, rc, user_msg, log_msg);
- sender_address = NULL;
- }
- break;
-
-
- /* The RCPT command requires an address as an operand. All we do
- here is to parse it for syntactic correctness. There may be any number
- of RCPT commands, specifying multiple senders. We build them all into
- a data structure that is in argc/argv format. The start/end values
- given by parse_extract_address are not used, as we keep only the
- extracted address. */
+ {
+ if (*smtp_cmd_data++ != '#')
+ {
+ done = synprot_error(L_smtp_syntax_error, 501, NULL,
+ US"argument must begin with #");
+ break;
+ }
+ etrn_command = US"exim -R";
+ argv = CUSS child_exec_exim(CEE_RETURN_ARGV, TRUE, NULL, TRUE,
+ *queue_name ? 4 : 2,
+ US"-R", smtp_cmd_data,
+ US"-MCG", queue_name);
+ }
+
+ /* If we are host-testing, don't actually do anything. */
+
+ if (host_checking)
+ {
+ HDEBUG(D_any)
+ {
+ debug_printf("ETRN command is: %s\n", etrn_command);
+ debug_printf("ETRN command execution skipped\n");
+ }
+ if (user_msg == NULL) smtp_printf("250 OK\r\n", FALSE);
+ else smtp_user_msg(US"250", user_msg);
+ break;
+ }
+
+
+ /* If ETRN queue runs are to be serialized, check the database to
+ ensure one isn't already running. */
+
+ if (smtp_etrn_serialize && !enq_start(etrn_serialize_key, 1))
+ {
+ smtp_printf("458 Already processing %s\r\n", FALSE, smtp_cmd_data);
+ break;
+ }
+
+ /* Fork a child process and run the command. We don't want to have to
+ wait for the process at any point, so set SIGCHLD to SIG_IGN before
+ forking. It should be set that way anyway for external incoming SMTP,
+ but we save and restore to be tidy. If serialization is required, we
+ actually run the command in yet another process, so we can wait for it
+ to complete and then remove the serialization lock. */
+
+ oldsignal = signal(SIGCHLD, SIG_IGN);
+
+ if ((pid = fork()) == 0)
+ {
+ smtp_input = FALSE; /* This process is not associated with the */
+ (void)fclose(smtp_in); /* SMTP call any more. */
+ (void)fclose(smtp_out);
+
+ signal(SIGCHLD, SIG_DFL); /* Want to catch child */
+
+ /* If not serializing, do the exec right away. Otherwise, fork down
+ into another process. */
+
+ if (!smtp_etrn_serialize || (pid = fork()) == 0)
+ {
+ DEBUG(D_exec) debug_print_argv(argv);
+ exim_nullstd(); /* Ensure std{in,out,err} exist */
+ execv(CS argv[0], (char *const *)argv);
+ log_write(0, LOG_MAIN|LOG_PANIC_DIE, "exec of \"%s\" (ETRN) failed: %s",
+ etrn_command, strerror(errno));
+ _exit(EXIT_FAILURE); /* paranoia */
+ }
+
+ /* Obey this if smtp_serialize and the 2nd fork yielded non-zero. That
+ is, we are in the first subprocess, after forking again. All we can do
+ for a failing fork is to log it. Otherwise, wait for the 2nd process to
+ complete, before removing the serialization. */
+
+ if (pid < 0)
+ log_write(0, LOG_MAIN|LOG_PANIC, "2nd fork for serialized ETRN "
+ "failed: %s", strerror(errno));
+ else
+ {
+ int status;
+ DEBUG(D_any) debug_printf("waiting for serialized ETRN process %d\n",
+ (int)pid);
+ (void)wait(&status);
+ DEBUG(D_any) debug_printf("serialized ETRN process %d ended\n",
+ (int)pid);
+ }
+
+ enq_end(etrn_serialize_key);
+ exim_underbar_exit(EXIT_SUCCESS);
+ }
+
+ /* Back in the top level SMTP process. Check that we started a subprocess
+ and restore the signal state. */
- case RCPT_CMD:
- rcpt_count++;
- was_rcpt = TRUE;
-
- /* There must be a sender address; if the sender was rejected and
- pipelining was advertised, we assume the client was pipelining, and do not
- count this as a protocol error. Reset was_rej_mail so that further RCPTs
- get the same treatment. */
-
- if (sender_address == NULL)
- {
- if (pipelining_advertised && last_was_rej_mail)
- {
- smtp_printf("503 sender not yet given\r\n");
- was_rej_mail = TRUE;
- }
+ if (pid < 0)
+ {
+ log_write(0, LOG_MAIN|LOG_PANIC, "fork of process for ETRN failed: %s",
+ strerror(errno));
+ smtp_printf("458 Unable to fork process\r\n", FALSE);
+ if (smtp_etrn_serialize) enq_end(etrn_serialize_key);
+ }
else
- {
- done = synprot_error(L_smtp_protocol_error, 503, NULL,
- US"sender not yet given");
- was_rcpt = FALSE; /* Not a valid RCPT */
- }
- rcpt_fail_count++;
+ if (!user_msg)
+ smtp_printf("250 OK\r\n", FALSE);
+ else
+ smtp_user_msg(US"250", user_msg);
+
+ signal(SIGCHLD, oldsignal);
break;
- }
- /* Check for an operand */
- if (smtp_command_argument[0] == 0)
- {
+ case BADARG_CMD:
done = synprot_error(L_smtp_syntax_error, 501, NULL,
- US"RCPT must have an address operand");
- rcpt_fail_count++;
+ US"unexpected argument data");
break;
- }
- /* Apply SMTP rewriting then extract the working address. Don't allow "<>"
- as a recipient address */
- recipient = ((rewrite_existflags & rewrite_smtp) != 0)?
- rewrite_one(smtp_command_argument, rewrite_smtp, NULL, FALSE, US"",
- global_rewrite_rules) : smtp_command_argument;
-
- /* rfc821_domains = TRUE; << no longer needed */
- recipient = parse_extract_address(recipient, &errmess, &start, &end,
- &recipient_domain, FALSE);
- /* rfc821_domains = FALSE; << no longer needed */
+ /* This currently happens only for NULLs, but could be extended. */
- if (recipient == NULL)
- {
- done = synprot_error(L_smtp_syntax_error, 501, smtp_command_argument, errmess);
- rcpt_fail_count++;
+ case BADCHAR_CMD:
+ done = synprot_error(L_smtp_syntax_error, 0, NULL, /* Just logs */
+ US"NUL character(s) present (shown as '?')");
+ smtp_printf("501 NUL characters are not allowed in SMTP commands\r\n",
+ FALSE);
break;
- }
-
- /* If the recipient address is unqualified, reject it, unless this is a
- locally generated message. However, unqualified addresses are permitted
- from a configured list of hosts and nets - typically when behaving as
- MUAs rather than MTAs. Sad that SMTP is used for both types of traffic,
- really. The flag is set at the start of the SMTP connection.
-
- RFC 1123 talks about supporting "the reserved mailbox postmaster"; I always
- assumed this meant "reserved local part", but the revision of RFC 821 and
- friends now makes it absolutely clear that it means *mailbox*. Consequently
- we must always qualify this address, regardless. */
- if (recipient_domain == 0)
- {
- if (allow_unqualified_recipient ||
- strcmpic(recipient, US"postmaster") == 0)
- {
- DEBUG(D_receive) debug_printf("unqualified address %s accepted\n",
- recipient);
- recipient_domain = Ustrlen(recipient) + 1;
- recipient = rewrite_address_qualify(recipient, TRUE);
- }
- else
- {
- rcpt_fail_count++;
- smtp_printf("501 %s: recipient address must contain a domain\r\n",
- smtp_command_argument);
- log_write(L_smtp_syntax_error,
- LOG_MAIN|LOG_REJECT, "unqualified recipient rejected: "
- "<%s> %s%s", recipient, host_and_ident(TRUE),
- host_lookup_msg);
- break;
- }
- }
-
- /* Check maximum allowed */
-
- if (rcpt_count > recipients_max && recipients_max > 0)
- {
- if (recipients_max_reject)
- {
- rcpt_fail_count++;
- smtp_printf("552 too many recipients\r\n");
- if (!toomany)
- log_write(0, LOG_MAIN|LOG_REJECT, "too many recipients: message "
- "rejected: sender=<%s> %s", sender_address, host_and_ident(TRUE));
- }
- else
- {
- rcpt_defer_count++;
- smtp_printf("452 too many recipients\r\n");
- if (!toomany)
- log_write(0, LOG_MAIN|LOG_REJECT, "too many recipients: excess "
- "temporarily rejected: sender=<%s> %s", sender_address,
- host_and_ident(TRUE));
- }
- toomany = TRUE;
+ case BADSYN_CMD:
+ SYNC_FAILURE:
+ if (smtp_inend >= smtp_inbuffer + IN_BUFFER_SIZE)
+ smtp_inend = smtp_inbuffer + IN_BUFFER_SIZE - 1;
+ c = smtp_inend - smtp_inptr;
+ if (c > 150) c = 150; /* limit logged amount */
+ smtp_inptr[c] = 0;
+ incomplete_transaction_log(US"sync failure");
+ log_write(0, LOG_MAIN|LOG_REJECT, "SMTP protocol synchronization error "
+ "(next input sent too soon: pipelining was%s advertised): "
+ "rejected \"%s\" %s next input=\"%s\"",
+ f.smtp_in_pipelining_advertised ? "" : " not",
+ smtp_cmd_buffer, host_and_ident(TRUE),
+ string_printing(smtp_inptr));
+ smtp_notquit_exit(US"synchronization-error", US"554",
+ US"SMTP synchronization error");
+ done = 1; /* Pretend eof - drops connection */
break;
- }
-
- /* If we have passed the threshold for rate limiting, apply the current
- delay, and update it for next time, provided this is a limited host. */
-
- if (rcpt_count > smtp_rlr_threshold &&
- verify_check_host(&smtp_ratelimit_hosts) == OK)
- {
- DEBUG(D_receive) debug_printf("rate limit RCPT: delay %.3g sec\n",
- smtp_delay_rcpt/1000.0);
- millisleep((int)smtp_delay_rcpt);
- smtp_delay_rcpt *= smtp_rlr_factor;
- if (smtp_delay_rcpt > (double)smtp_rlr_limit)
- smtp_delay_rcpt = (double)smtp_rlr_limit;
- }
-
- /* If the MAIL ACL discarded all the recipients, we bypass ACL checking
- for them. Otherwise, check the access control list for this recipient. */
-
- rc = recipients_discarded? DISCARD :
- acl_check(ACL_WHERE_RCPT, recipient, acl_smtp_rcpt, &user_msg, &log_msg);
-
- /* The ACL was happy */
-
- if (rc == OK)
- {
- smtp_printf("250 Accepted\r\n");
- receive_add_recipient(recipient, -1);
- }
-
- /* The recipient was discarded */
-
- else if (rc == DISCARD)
- {
- smtp_printf("250 Accepted\r\n");
- rcpt_fail_count++;
- discarded = TRUE;
- log_write(0, LOG_MAIN|LOG_REJECT, "%s F=<%s> rejected RCPT %s: "
- "discarded by %s ACL%s%s", host_and_ident(TRUE),
- (sender_address_unrewritten != NULL)?
- sender_address_unrewritten : sender_address,
- smtp_command_argument, recipients_discarded? "MAIL" : "RCPT",
- (log_msg == NULL)? US"" : US": ",
- (log_msg == NULL)? US"" : log_msg);
- }
-
- /* Either the ACL failed the address, or it was deferred. */
- else
- {
- if (rc == FAIL) rcpt_fail_count++; else rcpt_defer_count++;
- done = smtp_handle_acl_fail(ACL_WHERE_RCPT, rc, user_msg, log_msg);
- }
- break;
-
- /* The DATA command is legal only if it follows successful MAIL FROM
- and RCPT TO commands. However, if pipelining is advertised, a bad DATA is
- not counted as a protocol error if it follows RCPT (which must have been
- rejected if there are no recipients.) This function is complete when a
- valid DATA command is encountered.
-
- Note concerning the code used: RFC 2821 says this:
-
- - If there was no MAIL, or no RCPT, command, or all such commands
- were rejected, the server MAY return a "command out of sequence"
- (503) or "no valid recipients" (554) reply in response to the
- DATA command.
-
- The example in the pipelining RFC 2920 uses 554, but I use 503 here
- because it is the same whether pipelining is in use or not. */
-
- case DATA_CMD:
- if (!discarded && recipients_count <= 0)
- {
- if (pipelining_advertised && last_was_rcpt)
- smtp_printf("503 valid RCPT command must precede DATA\r\n");
- else
- done = synprot_error(L_smtp_protocol_error, 503, NULL,
- US"valid RCPT command must precede DATA");
+ case TOO_MANY_NONMAIL_CMD:
+ s = smtp_cmd_buffer;
+ while (*s != 0 && !isspace(*s)) s++;
+ incomplete_transaction_log(US"too many non-mail commands");
+ log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many "
+ "nonmail commands (last was \"%.*s\")", host_and_ident(FALSE),
+ (int)(s - smtp_cmd_buffer), smtp_cmd_buffer);
+ smtp_notquit_exit(US"bad-commands", US"554", US"Too many nonmail commands");
+ done = 1; /* Pretend eof - drops connection */
break;
- }
- if (toomany && recipients_max_reject)
- {
- sender_address = NULL; /* This will allow a new MAIL without RSET */
- sender_address_unrewritten = NULL;
- smtp_printf("554 Too many recipients\r\n");
+#ifdef SUPPORT_PROXY
+ case PROXY_FAIL_IGNORE_CMD:
+ smtp_printf("503 Command refused, required Proxy negotiation failed\r\n", FALSE);
break;
- }
-
- if (acl_smtp_predata == NULL) rc = OK; else
- {
- enable_dollar_recipients = TRUE;
- rc = acl_check(ACL_WHERE_PREDATA, NULL, acl_smtp_predata, &user_msg,
- &log_msg);
- enable_dollar_recipients = FALSE;
- }
-
- if (rc == OK)
- {
- smtp_printf("354 Enter message, ending with \".\" on a line by itself\r\n");
- done = 3;
- message_ended = END_NOTENDED; /* Indicate in middle of data */
- }
-
- /* Either the ACL failed the address, or it was deferred. */
-
- else
- done = smtp_handle_acl_fail(ACL_WHERE_PREDATA, rc, user_msg, log_msg);
-
- break;
-
-
- case VRFY_CMD:
- rc = acl_check(ACL_WHERE_VRFY, NULL, acl_smtp_vrfy, &user_msg, &log_msg);
- if (rc != OK)
- done = smtp_handle_acl_fail(ACL_WHERE_VRFY, rc, user_msg, log_msg);
- else
- {
- uschar *address;
- uschar *s = NULL;
-
- /* rfc821_domains = TRUE; << no longer needed */
- address = parse_extract_address(smtp_command_argument, &errmess, &start, &end,
- &recipient_domain, FALSE);
- /* rfc821_domains = FALSE; << no longer needed */
+#endif
- if (address == NULL)
- s = string_sprintf("501 %s", errmess);
+ default:
+ if (unknown_command_count++ >= smtp_max_unknown_commands)
+ {
+ log_write(L_smtp_syntax_error, LOG_MAIN,
+ "SMTP syntax error in \"%s\" %s %s",
+ string_printing(smtp_cmd_buffer), host_and_ident(TRUE),
+ US"unrecognized command");
+ incomplete_transaction_log(US"unrecognized command");
+ smtp_notquit_exit(US"bad-commands", US"500",
+ US"Too many unrecognized commands");
+ done = 2;
+ log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many "
+ "unrecognized commands (last was \"%s\")", host_and_ident(FALSE),
+ string_printing(smtp_cmd_buffer));
+ }
else
- {
- address_item *addr = deliver_make_addr(address, FALSE);
- switch(verify_address(addr, NULL, vopt_is_recipient | vopt_qualify, -1,
- -1, -1, NULL, NULL, NULL))
- {
- case OK:
- s = string_sprintf("250 <%s> is deliverable", address);
- break;
-
- case DEFER:
- s = (addr->message != NULL)?
- string_sprintf("451 <%s> %s", address, addr->message) :
- string_sprintf("451 Cannot resolve <%s> at this time", address);
- break;
-
- case FAIL:
- s = (addr->message != NULL)?
- string_sprintf("550 <%s> %s", address, addr->message) :
- string_sprintf("550 <%s> is not deliverable", address);
- log_write(0, LOG_MAIN, "VRFY failed for %s %s",
- smtp_command_argument, host_and_ident(TRUE));
- break;
- }
- }
-
- smtp_printf("%s\r\n", s);
- }
- break;
-
-
- case EXPN_CMD:
- rc = acl_check(ACL_WHERE_EXPN, NULL, acl_smtp_expn, &user_msg, &log_msg);
- if (rc != OK)
- done = smtp_handle_acl_fail(ACL_WHERE_EXPN, rc, user_msg, log_msg);
- else
- {
- BOOL save_log_testing_mode = log_testing_mode;
- address_test_mode = log_testing_mode = TRUE;
- (void) verify_address(deliver_make_addr(smtp_command_argument, FALSE),
- smtp_out, vopt_is_recipient | vopt_qualify | vopt_expn, -1, -1, -1,
- NULL, NULL, NULL);
- address_test_mode = FALSE;
- log_testing_mode = save_log_testing_mode; /* true for -bh */
- }
- break;
-
-
- #ifdef SUPPORT_TLS
-
- case STARTTLS_CMD:
- if (!tls_advertised)
- {
- done = synprot_error(L_smtp_protocol_error, 503, NULL,
- US"STARTTLS command used when not advertised");
+ done = synprot_error(L_smtp_syntax_error, 500, NULL,
+ US"unrecognized command");
break;
- }
-
- /* Apply an ACL check if one is defined */
-
- if (acl_smtp_starttls != NULL)
- {
- rc = acl_check(ACL_WHERE_STARTTLS, NULL, acl_smtp_starttls, &user_msg,
- &log_msg);
- if (rc != OK)
- {
- done = smtp_handle_acl_fail(ACL_WHERE_STARTTLS, rc, user_msg, log_msg);
- break;
- }
- }
-
- /* RFC 2487 is not clear on when this command may be sent, though it
- does state that all information previously obtained from the client
- must be discarded if a TLS session is started. It seems reasonble to
- do an implied RSET when STARTTLS is received. */
-
- incomplete_transaction_log(US"STARTTLS");
- smtp_reset(reset_point);
- toomany = FALSE;
- cmd_list[CMD_LIST_STARTTLS].is_mail_cmd = FALSE;
-
- /* Attempt to start up a TLS session, and if successful, discard all
- knowledge that was obtained previously. At least, that's what the RFC says,
- and that's what happens by default. However, in order to work round YAEB,
- there is an option to remember the esmtp state. Sigh.
-
- We must allow for an extra EHLO command and an extra AUTH command after
- STARTTLS that don't add to the nonmail command count. */
-
- if ((rc = tls_server_start(tls_require_ciphers)) == OK)
- {
- if (!tls_remember_esmtp)
- helo_seen = esmtp = auth_advertised = pipelining_advertised = FALSE;
- cmd_list[CMD_LIST_EHLO].is_mail_cmd = TRUE;
- cmd_list[CMD_LIST_AUTH].is_mail_cmd = TRUE;
- if (sender_helo_name != NULL)
- {
- store_free(sender_helo_name);
- sender_helo_name = NULL;
- host_build_sender_fullhost(); /* Rebuild */
- set_process_info("handling incoming TLS connection from %s",
- host_and_ident(FALSE));
- }
- received_protocol = (esmtp?
- protocols[pextend + pcrpted +
- ((sender_host_authenticated != NULL)? pauthed : 0)]
- :
- protocols[pnormal + pcrpted])
- +
- ((sender_host_address != NULL)? pnlocal : 0);
-
- sender_host_authenticated = NULL;
- authenticated_id = NULL;
- sync_cmd_limit = NON_SYNC_CMD_NON_PIPELINING;
- DEBUG(D_tls) debug_printf("TLS active\n");
- break; /* Successful STARTTLS */
- }
-
- /* Some local configuration problem was discovered before actually trying
- to do a TLS handshake; give a temporary error. */
-
- else if (rc == DEFER)
- {
- smtp_printf("454 TLS currently unavailable\r\n");
- break;
- }
-
- /* Hard failure. Reject everything except QUIT or closed connection. One
- cause for failure is a nested STARTTLS, in which case tls_active remains
- set, but we must still reject all incoming commands. */
-
- DEBUG(D_tls) debug_printf("TLS failed to start\n");
- while (done <= 0)
- {
- switch(smtp_read_command(FALSE))
- {
- case EOF_CMD:
- log_write(L_smtp_connection, LOG_MAIN, "%s closed by EOF",
- smtp_get_connection_info());
- done = 2;
- break;
-
- case QUIT_CMD:
- smtp_printf("221 %s closing connection\r\n", smtp_active_hostname);
- log_write(L_smtp_connection, LOG_MAIN, "%s closed by QUIT",
- smtp_get_connection_info());
- done = 2;
- break;
-
- default:
- smtp_printf("554 Security failure\r\n");
- break;
- }
- }
- tls_close(TRUE);
- break;
- #endif
-
-
- /* The ACL for QUIT is provided for gathering statistical information or
- similar; it does not affect the response code, but it can supply a custom
- message. */
-
- case QUIT_CMD:
- incomplete_transaction_log(US"QUIT");
-
- if (acl_smtp_quit != NULL)
- {
- rc = acl_check(ACL_WHERE_QUIT, NULL, acl_smtp_quit,&user_msg,&log_msg);
- if (rc == ERROR)
- log_write(0, LOG_MAIN|LOG_PANIC, "ACL for QUIT returned ERROR: %s",
- log_msg);
- }
- else user_msg = NULL;
-
- if (user_msg == NULL)
- smtp_printf("221 %s closing connection\r\n", smtp_active_hostname);
- else
- smtp_printf("221 %s\r\n", user_msg);
-
- #ifdef SUPPORT_TLS
- tls_close(TRUE);
- #endif
-
- done = 2;
- log_write(L_smtp_connection, LOG_MAIN, "%s closed by QUIT",
- smtp_get_connection_info());
- break;
-
-
- case RSET_CMD:
- incomplete_transaction_log(US"RSET");
- smtp_reset(reset_point);
- toomany = FALSE;
- smtp_printf("250 Reset OK\r\n");
- cmd_list[CMD_LIST_RSET].is_mail_cmd = FALSE;
- break;
-
-
- case NOOP_CMD:
- smtp_printf("250 OK\r\n");
- break;
-
-
- /* Show ETRN/EXPN/VRFY if there's
- an ACL for checking hosts; if actually used, a check will be done for
- permitted hosts. */
-
- case HELP_CMD:
- smtp_printf("214-Commands supported:\r\n");
- {
- uschar buffer[256];
- buffer[0] = 0;
- Ustrcat(buffer, " AUTH");
- #ifdef SUPPORT_TLS
- Ustrcat(buffer, " STARTTLS");
- #endif
- Ustrcat(buffer, " HELO EHLO MAIL RCPT DATA");
- Ustrcat(buffer, " NOOP QUIT RSET HELP");
- if (acl_smtp_etrn != NULL) Ustrcat(buffer, " ETRN");
- if (acl_smtp_expn != NULL) Ustrcat(buffer, " EXPN");
- if (acl_smtp_vrfy != NULL) Ustrcat(buffer, " VRFY");
- smtp_printf("214%s\r\n", buffer);
- }
- break;
-
-
- case EOF_CMD:
- incomplete_transaction_log(US"connection lost");
- smtp_printf("421 %s lost input connection\r\n", smtp_active_hostname);
-
- /* Don't log by default unless in the middle of a message, as some mailers
- just drop the call rather than sending QUIT, and it clutters up the logs.
- */
-
- if (sender_address != NULL || recipients_count > 0)
- log_write(L_lost_incoming_connection,
- LOG_MAIN,
- "unexpected %s while reading SMTP command from %s%s",
- sender_host_unknown? "EOF" : "disconnection",
- host_and_ident(FALSE), smtp_read_error);
-
- else log_write(L_smtp_connection, LOG_MAIN, "%s lost%s",
- smtp_get_connection_info(), smtp_read_error);
-
- done = 1;
- break;
-
-
- case ETRN_CMD:
- if (sender_address != NULL)
- {
- done = synprot_error(L_smtp_protocol_error, 503, NULL,
- US"ETRN is not permitted inside a transaction");
- break;
- }
-
- log_write(L_etrn, LOG_MAIN, "ETRN %s received from %s", smtp_command_argument,
- host_and_ident(FALSE));
-
- rc = acl_check(ACL_WHERE_ETRN, NULL, acl_smtp_etrn, &user_msg, &log_msg);
- if (rc != OK)
- {
- done = smtp_handle_acl_fail(ACL_WHERE_ETRN, rc, user_msg, log_msg);
- break;
- }
-
- /* Compute the serialization key for this command. */
-
- etrn_serialize_key = string_sprintf("etrn-%s\n", smtp_command_argument);
-
- /* If a command has been specified for running as a result of ETRN, we
- permit any argument to ETRN. If not, only the # standard form is permitted,
- since that is strictly the only kind of ETRN that can be implemented
- according to the RFC. */
-
- if (smtp_etrn_command != NULL)
- {
- uschar *error;
- BOOL rc;
- etrn_command = smtp_etrn_command;
- deliver_domain = smtp_command_argument;
- rc = transport_set_up_command(&argv, smtp_etrn_command, TRUE, 0, NULL,
- US"ETRN processing", &error);
- deliver_domain = NULL;
- if (!rc)
- {
- log_write(0, LOG_MAIN|LOG_PANIC, "failed to set up ETRN command: %s",
- error);
- smtp_printf("458 Internal failure\r\n");
- break;
- }
- }
-
- /* Else set up to call Exim with the -R option. */
-
- else
- {
- if (*smtp_command_argument++ != '#')
- {
- done = synprot_error(L_smtp_syntax_error, 501, NULL,
- US"argument must begin with #");
- break;
- }
- etrn_command = US"exim -R";
- argv = child_exec_exim(CEE_RETURN_ARGV, TRUE, NULL, TRUE, 2, US"-R",
- smtp_command_argument);
- }
-
- /* If we are host-testing, don't actually do anything. */
-
- if (host_checking)
- {
- HDEBUG(D_any)
- {
- debug_printf("ETRN command is: %s\n", etrn_command);
- debug_printf("ETRN command execution skipped\n");
- }
- smtp_printf("250 OK\r\n");
- break;
- }
-
-
- /* If ETRN queue runs are to be serialized, check the database to
- ensure one isn't already running. */
-
- if (smtp_etrn_serialize && !enq_start(etrn_serialize_key))
- {
- smtp_printf("458 Already processing %s\r\n", smtp_command_argument);
- break;
- }
-
- /* Fork a child process and run the command. We don't want to have to
- wait for the process at any point, so set SIGCHLD to SIG_IGN before
- forking. It should be set that way anyway for external incoming SMTP,
- but we save and restore to be tidy. If serialization is required, we
- actually run the command in yet another process, so we can wait for it
- to complete and then remove the serialization lock. */
-
- oldsignal = signal(SIGCHLD, SIG_IGN);
-
- if ((pid = fork()) == 0)
- {
- smtp_input = FALSE; /* This process is not associated with the */
- (void)fclose(smtp_in); /* SMTP call any more. */
- (void)fclose(smtp_out);
-
- signal(SIGCHLD, SIG_DFL); /* Want to catch child */
-
- /* If not serializing, do the exec right away. Otherwise, fork down
- into another process. */
-
- if (!smtp_etrn_serialize || (pid = fork()) == 0)
- {
- DEBUG(D_exec) debug_print_argv(argv);
- exim_nullstd(); /* Ensure std{in,out,err} exist */
- execv(CS argv[0], (char *const *)argv);
- log_write(0, LOG_MAIN|LOG_PANIC_DIE, "exec of \"%s\" (ETRN) failed: %s",
- etrn_command, strerror(errno));
- _exit(EXIT_FAILURE); /* paranoia */
- }
-
- /* Obey this if smtp_serialize and the 2nd fork yielded non-zero. That
- is, we are in the first subprocess, after forking again. All we can do
- for a failing fork is to log it. Otherwise, wait for the 2nd process to
- complete, before removing the serialization. */
-
- if (pid < 0)
- log_write(0, LOG_MAIN|LOG_PANIC, "2nd fork for serialized ETRN "
- "failed: %s", strerror(errno));
- else
- {
- int status;
- DEBUG(D_any) debug_printf("waiting for serialized ETRN process %d\n",
- (int)pid);
- (void)wait(&status);
- DEBUG(D_any) debug_printf("serialized ETRN process %d ended\n",
- (int)pid);
- }
-
- enq_end(etrn_serialize_key);
- _exit(EXIT_SUCCESS);
- }
-
- /* Back in the top level SMTP process. Check that we started a subprocess
- and restore the signal state. */
-
- if (pid < 0)
- {
- log_write(0, LOG_MAIN|LOG_PANIC, "fork of process for ETRN failed: %s",
- strerror(errno));
- smtp_printf("458 Unable to fork process\r\n");
- if (smtp_etrn_serialize) enq_end(etrn_serialize_key);
- }
- else smtp_printf("250 OK\r\n");
-
- signal(SIGCHLD, oldsignal);
- break;
-
-
- case BADARG_CMD:
- done = synprot_error(L_smtp_syntax_error, 501, NULL,
- US"unexpected argument data");
- break;
-
-
- /* This currently happens only for NULLs, but could be extended. */
-
- case BADCHAR_CMD:
- done = synprot_error(L_smtp_syntax_error, 0, NULL, /* Just logs */
- US"NULL character(s) present (shown as '?')");
- smtp_printf("501 NULL characters are not allowed in SMTP commands\r\n");
- break;
-
-
- case BADSYN_CMD:
- if (smtp_inend >= smtp_inbuffer + in_buffer_size)
- smtp_inend = smtp_inbuffer + in_buffer_size - 1;
- c = smtp_inend - smtp_inptr;
- if (c > 150) c = 150;
- smtp_inptr[c] = 0;
- incomplete_transaction_log(US"sync failure");
- log_write(0, LOG_MAIN|LOG_REJECT, "SMTP protocol synchronization error "
- "(next input sent too soon: pipelining was%s advertised): "
- "rejected \"%s\" %s next input=\"%s\"",
- pipelining_advertised? "" : " not",
- cmd_buffer, host_and_ident(TRUE),
- string_printing(smtp_inptr));
- smtp_printf("554 SMTP synchronization error\r\n");
- done = 1; /* Pretend eof - drops connection */
- break;
-
-
- case TOO_MANY_NONMAIL_CMD:
- incomplete_transaction_log(US"too many non-mail commands");
- log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many "
- "nonmail commands (last was \"%.*s\")", host_and_ident(FALSE),
- smtp_command_argument - cmd_buffer, cmd_buffer);
- smtp_printf("554 Too many nonmail commands\r\n");
- done = 1; /* Pretend eof - drops connection */
- break;
-
-
- default:
- if (unknown_command_count++ >= smtp_max_unknown_commands)
- {
- log_write(L_smtp_syntax_error, LOG_MAIN,
- "SMTP syntax error in \"%s\" %s %s",
- string_printing(cmd_buffer), host_and_ident(TRUE),
- US"unrecognized command");
- incomplete_transaction_log(US"unrecognized command");
- smtp_printf("500 Too many unrecognized commands\r\n");
- done = 2;
- log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many "
- "unrecognized commands (last was \"%s\")", host_and_ident(FALSE),
- cmd_buffer);
- }
- else
- done = synprot_error(L_smtp_syntax_error, 500, NULL,
- US"unrecognized command");
- break;
}
/* This label is used by goto's inside loops that want to break out to
return done - 2; /* Convert yield values */
}
+
+
+gstring *
+authres_smtpauth(gstring * g)
+{
+if (!sender_host_authenticated)
+ return g;
+
+g = string_append(g, 2, US";\n\tauth=pass (", sender_host_auth_pubname);
+
+if (Ustrcmp(sender_host_auth_pubname, "tls") != 0)
+ g = string_append(g, 2, US") smtp.auth=", authenticated_id);
+else if (authenticated_id)
+ g = string_append(g, 2, US") x509.auth=", authenticated_id);
+else
+ g = string_catn(g, US") reason=x509.auth", 17);
+
+if (authenticated_sender)
+ g = string_append(g, 2, US" smtp.mailfrom=", authenticated_sender);
+return g;
+}
+
+
+
+/* vi: aw ai sw=2
+*/
/* End of smtp_in.c */
git://git.exim.org / exim.git / blobdiff