* Exim - an Internet mail transport agent *
*************************************************/
+/* Copyright (c) The Exim Maintainers 2020 - 2022 */
/* Copyright (c) University of Cambridge 1995 - 2018 */
-/* Copyright (c) The Exim Maintainers 2020 */
/* See the file NOTICE for conditions of use and distribution. */
+/* SPDX-License-Identifier: GPL-2.0-or-later */
/* Functions for handling an incoming SMTP call. */
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 = {.tv_sec = 0, .tv_usec = 0};
-
-#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);
-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;
-}
-
-
-#ifndef DISABLE_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 *
*************************************************/
if (recipients_count > 0)
{
- raw_recipients = store_get(recipients_count * sizeof(uschar *), FALSE);
+ raw_recipients = store_get(recipients_count * sizeof(uschar *), GET_UNTAINTED);
for (int i = 0; i < recipients_count; i++)
raw_recipients[i] = recipients_list[i].address;
raw_recipients_count = recipients_count;
}
+/******************************************************************************/
+/* SMTP input buffer handling. Most of these are similar to stdio routines. */
+
+static void
+smtp_buf_init(void)
+{
+/* Set up the buffer for inputting using direct read() calls, and arrange to
+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. */
+
+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';
+
+smtp_inptr = smtp_inend = smtp_inbuffer;
+smtp_had_eof = smtp_had_error = 0;
+}
+
+
/* Refill the buffer, and notify DKIM verification code.
Return false for error or EOF.
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);
return TRUE;
}
-/*************************************************
-* SMTP version of getc() *
-*************************************************/
-/* This gets the next byte from the SMTP input buffer. If the buffer is empty,
+/* Check if there is buffered data */
+
+BOOL
+smtp_hasc(void)
+{
+return smtp_inptr < smtp_inend;
+}
+
+/* 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 negotiated itself into an TLS/SSL state.
int
smtp_getc(unsigned lim)
{
-if (smtp_inptr >= smtp_inend)
- if (!smtp_refill(lim))
- return EOF;
+if (!smtp_hasc() && !smtp_refill(lim)) return EOF;
return *smtp_inptr++;
}
+/* Get many bytes, refilling buffer if needed */
+
uschar *
smtp_getbuf(unsigned * len)
{
unsigned size;
uschar * buf;
-if (smtp_inptr >= smtp_inend)
- if (!smtp_refill(*len))
- { *len = 0; return NULL; }
+if (!smtp_hasc() && !smtp_refill(*len))
+ { *len = 0; return NULL; }
if ((size = smtp_inend - smtp_inptr) > *len) size = *len;
buf = smtp_inptr;
return buf;
}
+/* Copy buffered data to the dkim feed.
+Called, unless TLS, just before starting to read message headers. */
+
void
smtp_get_cache(unsigned lim)
{
}
+/* SMTP version of ungetc()
+Puts a character back in the input buffer. Only ever called once.
+
+Arguments:
+ ch the character
+
+Returns: the character
+*/
+
+int
+smtp_ungetc(int ch)
+{
+if (smtp_inptr <= smtp_inbuffer) /* NB: NOT smtp_hasc() ! */
+ log_write(0, LOG_MAIN|LOG_PANIC_DIE, "buffer underflow in smtp_ungetc");
+
+*--smtp_inptr = ch;
+return ch;
+}
+
+
+/* SMTP version of feof()
+Tests for a previous EOF
+
+Arguments: none
+Returns: non-zero if the eof flag is set
+*/
+
+int
+smtp_feof(void)
+{
+return smtp_had_eof;
+}
+
+
+/* SMTP version of ferror()
+Tests for a previous read error, and returns with errno
+restored to what it was when the error was detected.
+
+Arguments: none
+Returns: non-zero if the error flag is set
+*/
+
+int
+smtp_ferror(void)
+{
+errno = smtp_had_error;
+return smtp_had_error;
+}
+
+
+/* Check if a getc will block or not */
+
+static BOOL
+smtp_could_getc(void)
+{
+int fd, rc;
+fd_set fds;
+struct timeval tzero = {.tv_sec = 0, .tv_usec = 0};
+
+if (smtp_inptr < smtp_inend)
+ return TRUE;
+
+fd = fileno(smtp_in);
+FD_ZERO(&fds);
+FD_SET(fd, &fds);
+rc = select(fd + 1, (SELECT_ARG2_TYPE *)&fds, NULL, NULL, &tzero);
+
+if (rc <= 0) return FALSE; /* Not ready to read */
+rc = smtp_getc(GETC_BUFFER_UNLIMITED);
+if (rc < 0) return FALSE; /* End of file or error */
+
+smtp_ungetc(rc);
+return TRUE;
+}
+
+
+/******************************************************************************/
+/*************************************************
+* 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)
+{
+#ifndef DISABLE_TLS
+if (tls_in.active.sock >= 0)
+ return !tls_could_getc();
+#endif
+
+return !smtp_could_getc();
+}
+
+static BOOL
+check_sync(void)
+{
+if (!smtp_enforce_sync || !sender_host_address || f.sender_host_notsocket)
+ return TRUE;
+
+return wouldblock_reading();
+}
+
+
+/******************************************************************************/
+/* Variants of the smtp_* input handling functions for use in CHUNKING mode */
+
/* Forward declarations */
static inline void bdat_push_receive_functions(void);
static inline void bdat_pop_receive_functions(void);
}
}
+BOOL
+bdat_hasc(void)
+{
+if (chunking_data_left > 0)
+ return lwr_receive_hasc();
+return TRUE;
+}
+
uschar *
bdat_getbuf(unsigned * len)
{
}
bdat_pop_receive_functions();
-
-if (chunking_state != CHUNKING_LAST)
- {
- chunking_state = CHUNKING_OFFERED;
- DEBUG(D_receive) debug_printf("chunking state %d\n", (int)chunking_state);
- }
+chunking_state = CHUNKING_OFFERED;
+DEBUG(D_receive) debug_printf("chunking state %d\n", (int)chunking_state);
}
/* 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. */
-if (lwr_receive_getc == NULL)
+if (!lwr_receive_getc)
{
lwr_receive_getc = receive_getc;
lwr_receive_getbuf = receive_getbuf;
+ lwr_receive_hasc = receive_hasc;
lwr_receive_ungetc = receive_ungetc;
}
else
receive_getc = bdat_getc;
receive_getbuf = bdat_getbuf;
+receive_hasc = bdat_hasc;
receive_ungetc = bdat_ungetc;
}
static inline void
bdat_pop_receive_functions(void)
{
-if (lwr_receive_getc == NULL)
+if (!lwr_receive_getc)
{
DEBUG(D_receive) debug_printf("chunking double-pop receive functions\n");
return;
}
receive_getc = lwr_receive_getc;
receive_getbuf = lwr_receive_getbuf;
+receive_hasc = lwr_receive_hasc;
receive_ungetc = lwr_receive_ungetc;
lwr_receive_getc = NULL;
lwr_receive_getbuf = NULL;
+lwr_receive_hasc = NULL;
lwr_receive_ungetc = NULL;
}
-/*************************************************
-* SMTP version of ungetc() *
-*************************************************/
-
-/* Puts a character back in the input buffer. Only ever
-called once.
-
-Arguments:
- ch the character
-
-Returns: the character
-*/
-
-int
-smtp_ungetc(int ch)
-{
-if (smtp_inptr <= smtp_inbuffer)
- log_write(0, LOG_MAIN|LOG_PANIC_DIE, "buffer underflow in smtp_ungetc");
-
-*--smtp_inptr = ch;
-return ch;
-}
-
-
int
bdat_ungetc(int ch)
{
-/*************************************************
-* SMTP version of feof() *
-*************************************************/
-
-/* Tests for a previous EOF
-
-Arguments: none
-Returns: non-zero if the eof flag is set
-*/
-
-int
-smtp_feof(void)
-{
-return smtp_had_eof;
-}
-
-
-
-
-/*************************************************
-* SMTP version of ferror() *
-*************************************************/
-
-/* Tests for a previous read error, and returns with errno
-restored to what it was when the error was detected.
-
-Arguments: none
-Returns: non-zero if the error flag is set
-*/
-
-int
-smtp_ferror(void)
-{
-errno = smtp_had_error;
-return smtp_had_error;
-}
-
-
-
-/*************************************************
-* 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 *
yield = !! string_vformat(&gs, SVFMT_TAINT_NOCHK, format, ap);
string_from_gstring(&gs);
-DEBUG(D_receive)
- {
- 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);
- }
+DEBUG(D_receive) for (const uschar * t, * s = gs.s;
+ s && (t = Ustrchr(s, '\r'));
+ s = t + 2) /* \r\n */
+ debug_printf("%s %.*s\n",
+ s == gs.s ? "SMTP>>" : " ",
+ (int)(t - s), s);
if (!yield)
{
if (fl.rcpt_in_progress)
{
- if (rcpt_smtp_response == NULL)
+ if (!rcpt_smtp_response)
rcpt_smtp_response = string_copy(big_buffer);
else if (fl.rcpt_smtp_response_same &&
Ustrcmp(rcpt_smtp_response, big_buffer) != 0)
+/* 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;
+}
+
+
+#ifndef DISABLE_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
+
/*************************************************
* SMTP command read timeout *
*************************************************/
|| 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 */
- !f.sender_host_notsocket) /* Really is a socket */
+ 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 */
+ && !f.sender_host_notsocket /* Really is a socket */
+ )
return BADSYN_CMD;
/* The variables $smtp_command and $smtp_command_argument point into the
&& 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 */
+ && !f.sender_host_notsocket /* Really is a socket */
+ )
return BADSYN_CMD;
return OTHER_CMD;
*/
void
-smtp_closedown(uschar *message)
+smtp_closedown(uschar * message)
{
if (!smtp_in || smtp_batched_input) return;
receive_swallow_smtp();
#ifdef SUPPORT_I18N
message_smtputf8 = FALSE;
#endif
+#ifdef WITH_CONTENT_SCAN
+regex_vars_clear();
+#endif
body_linecount = body_zerocount = 0;
+lookup_value = NULL; /* Can be set by ACL */
sender_rate = sender_rate_limit = sender_rate_period = NULL;
ratelimiters_mail = NULL; /* Updated by ratelimit ACL condition */
/* Note that ratelimiters_conn persists across resets. */
#ifndef DISABLE_TLS
static BOOL
-smtp_log_tls_fail(uschar * errstr)
+smtp_log_tls_fail(const uschar * errstr)
{
-uschar * conn_info = smtp_get_connection_info();
+const 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 */
#endif
+static void
+log_connect_tls_drop(const uschar * what, const uschar * log_msg)
+{
+gstring * g = s_tlslog(NULL);
+uschar * tls = string_from_gstring(g);
+
+log_write(L_connection_reject,
+ log_reject_target, "%s%s%s dropped by %s%s%s",
+ LOGGING(dnssec) && sender_host_dnssec ? US" DS" : US"",
+ host_and_ident(TRUE),
+ tls ? tls : US"",
+ what,
+ log_msg ? US": " : US"", log_msg);
+}
+
+
/*************************************************
* Start an SMTP session *
*************************************************/
/* Allow for trailing 0 in the command and data buffers. Tainted. */
-smtp_cmd_buffer = store_get_perm(2*SMTP_CMD_BUFFER_SIZE + 2, TRUE);
+smtp_cmd_buffer = store_get_perm(2*SMTP_CMD_BUFFER_SIZE + 2, GET_TAINTED);
smtp_cmd_buffer[0] = 0;
smtp_data_buffer = smtp_cmd_buffer + SMTP_CMD_BUFFER_SIZE + 1;
(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. Place a NUL at the
-end of the buffer to safety-stop C-string reads from it. */
+call the local functions instead of the standard C ones. */
-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';
+smtp_buf_init();
receive_getc = smtp_getc;
receive_getbuf = smtp_getbuf;
receive_get_cache = smtp_get_cache;
+receive_hasc = smtp_hasc;
receive_ungetc = smtp_ungetc;
receive_feof = smtp_feof;
receive_ferror = smtp_ferror;
-receive_smtp_buffered = smtp_buffered;
lwr_receive_getc = NULL;
lwr_receive_getbuf = NULL;
+lwr_receive_hasc = NULL;
lwr_receive_ungetc = NULL;
-smtp_inptr = smtp_inend = smtp_inbuffer;
-smtp_had_eof = smtp_had_error = 0;
/* Set up the message size limit; this may be host-specific */
#if !HAVE_IPV6 && !defined(NO_IP_OPTIONS)
- #ifdef GLIBC_IP_OPTIONS
- #if (!defined __GLIBC__) || (__GLIBC__ < 2)
- #define OPTSTYLE 1
- #else
- #define OPTSTYLE 2
- #endif
- #elif defined DARWIN_IP_OPTIONS
- #define OPTSTYLE 2
- #else
- #define OPTSTYLE 3
- #endif
+# ifdef GLIBC_IP_OPTIONS
+# if (!defined __GLIBC__) || (__GLIBC__ < 2)
+# define OPTSTYLE 1
+# else
+# define OPTSTYLE 2
+# endif
+# elif defined DARWIN_IP_OPTIONS
+# define OPTSTYLE 2
+# else
+# define OPTSTYLE 3
+# endif
if (!host_checking && !f.sender_host_notsocket)
{
- #if OPTSTYLE == 1
+# if OPTSTYLE == 1
EXIM_SOCKLEN_T optlen = sizeof(struct ip_options) + MAX_IPOPTLEN;
- struct ip_options *ipopt = store_get(optlen, FALSE);
- #elif OPTSTYLE == 2
+ struct ip_options *ipopt = store_get(optlen, GET_UNTAINTED);
+# elif OPTSTYLE == 2
struct ip_opts ipoptblock;
struct ip_opts *ipopt = &ipoptblock;
EXIM_SOCKLEN_T optlen = sizeof(ipoptblock);
- #else
+# else
struct ipoption ipoptblock;
struct ipoption *ipopt = &ipoptblock;
EXIM_SOCKLEN_T optlen = sizeof(ipoptblock);
- #endif
+# endif
/* Occasional genuine failures of getsockopt() have been seen - for
example, "reset by peer". Therefore, just log and give up on this
else if (optlen > 0)
{
- uschar *p = big_buffer;
- uschar *pend = big_buffer + big_buffer_size;
- uschar *adptr;
+ uschar * p = big_buffer;
+ uschar * pend = big_buffer + big_buffer_size;
+ uschar * adptr;
int optcount;
struct in_addr addr;
- #if OPTSTYLE == 1
- uschar *optstart = US (ipopt->__data);
- #elif OPTSTYLE == 2
- uschar *optstart = US (ipopt->ip_opts);
- #else
- uschar *optstart = US (ipopt->ipopt_list);
- #endif
+# if OPTSTYLE == 1
+ uschar * optstart = US (ipopt->__data);
+# elif OPTSTYLE == 2
+ uschar * optstart = US (ipopt->ip_opts);
+# else
+ uschar * optstart = US (ipopt->ipopt_list);
+# endif
DEBUG(D_receive) debug_printf("IP options exist\n");
switch (*opt)
{
case IPOPT_EOL:
- opt = NULL;
- break;
+ opt = NULL;
+ break;
case IPOPT_NOP:
- opt++;
- break;
+ opt++;
+ break;
case IPOPT_SSRR:
case IPOPT_LSRR:
- if (!string_format(p, pend-p, " %s [@%s",
- (*opt == IPOPT_SSRR)? "SSRR" : "LSRR",
- #if OPTSTYLE == 1
- inet_ntoa(*((struct in_addr *)(&(ipopt->faddr))))))
- #elif OPTSTYLE == 2
- inet_ntoa(ipopt->ip_dst)))
- #else
- inet_ntoa(ipopt->ipopt_dst)))
- #endif
- {
- opt = NULL;
- break;
- }
+ if (!
+# if OPTSTYLE == 1
+ string_format(p, pend-p, " %s [@%s",
+ (*opt == IPOPT_SSRR)? "SSRR" : "LSRR",
+ inet_ntoa(*((struct in_addr *)(&(ipopt->faddr)))))
+# elif OPTSTYLE == 2
+ string_format(p, pend-p, " %s [@%s",
+ (*opt == IPOPT_SSRR)? "SSRR" : "LSRR",
+ inet_ntoa(ipopt->ip_dst))
+# else
+ string_format(p, pend-p, " %s [@%s",
+ (*opt == IPOPT_SSRR)? "SSRR" : "LSRR",
+ inet_ntoa(ipopt->ipopt_dst))
+# endif
+ )
+ {
+ opt = NULL;
+ break;
+ }
- p += Ustrlen(p);
- optcount = (opt[1] - 3) / sizeof(struct in_addr);
- adptr = opt + 3;
- while (optcount-- > 0)
- {
- memcpy(&addr, adptr, sizeof(addr));
- if (!string_format(p, pend - p - 1, "%s%s",
- (optcount == 0)? ":" : "@", inet_ntoa(addr)))
- {
- opt = NULL;
- break;
- }
- p += Ustrlen(p);
- adptr += sizeof(struct in_addr);
- }
- *p++ = ']';
- opt += opt[1];
- break;
+ p += Ustrlen(p);
+ optcount = (opt[1] - 3) / sizeof(struct in_addr);
+ adptr = opt + 3;
+ while (optcount-- > 0)
+ {
+ memcpy(&addr, adptr, sizeof(addr));
+ if (!string_format(p, pend - p - 1, "%s%s",
+ (optcount == 0)? ":" : "@", inet_ntoa(addr)))
+ {
+ opt = NULL;
+ break;
+ }
+ p += Ustrlen(p);
+ adptr += sizeof(struct in_addr);
+ }
+ *p++ = ']';
+ opt += opt[1];
+ break;
default:
- {
- if (pend - p < 4 + 3*opt[1]) { opt = NULL; break; }
- Ustrcat(p, "[ ");
- p += 2;
- for (int i = 0; i < opt[1]; i++)
- p += sprintf(CS p, "%2.2x ", opt[i]);
- *p++ = ']';
- }
- opt += opt[1];
- break;
+ {
+ if (pend - p < 4 + 3*opt[1]) { opt = NULL; break; }
+ Ustrcat(p, "[ ");
+ p += 2;
+ 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(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", FALSE);
+#ifndef DISABLE_TLS
+ if (!tls_in.on_connect)
+#endif
+ smtp_printf("554 SMTP service not available\r\n", FALSE);
return FALSE;
}
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(&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 */
user_msg = NULL;
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);
+#ifndef DISABLE_TLS
+ if (tls_in.on_connect)
+ log_connect_tls_drop(US"'connect' ACL", log_msg);
+ else
+#endif
+ (void) smtp_handle_acl_fail(ACL_WHERE_CONNECT, rc, user_msg, log_msg);
return 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. */
+
+#ifndef DISABLE_TLS
+if (tls_in.on_connect)
+ {
+ if (tls_server_start(&user_msg) != OK)
+ return smtp_log_tls_fail(user_msg);
+ cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd = TRUE;
+ }
+#endif
+
/* Output the initial message for a two-way SMTP connection. It may contain
newlines, which then cause a multi-line response to be given. */
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
+if (user_msg)
{
int codelen = 3;
s = user_msg;
esclen = codelen - 4;
}
}
+else if (!(s = expand_string(smtp_banner)))
+ {
+ log_write(0, f.expand_string_forcedfail ? LOG_MAIN : LOG_MAIN|LOG_PANIC_DIE,
+ "Expansion of \"%s\" (smtp_banner) failed: %s",
+ smtp_banner, expand_string_message);
+ /* for force-fail */
+#ifndef DISABLE_TLS
+ if (tls_in.on_connect) tls_close(NULL, TLS_SHUTDOWN_WAIT);
+#endif
+ return FALSE;
+ }
/* Remove any terminating newlines; might as well remove trailing space too */
smtp_message_code(uschar **code, int *codelen, uschar **msg, uschar **log_msg,
BOOL check_valid)
{
-int n;
-int ovector[3];
+uschar * match;
+int len;
-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 (!msg || !*msg || !regex_match(regex_smtp_code, *msg, -1, &match))
+ return;
+len = Ustrlen(match);
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]);
+ if (log_msg && *log_msg == *msg)
+ *log_msg = string_sprintf("%s %s", *code, *log_msg + len);
}
else
{
*code = *msg;
- *codelen = ovector[1]; /* Includes final space */
+ *codelen = len; /* Includes final space */
}
-*msg += ovector[1]; /* Chop the code off the message */
+*msg += len; /* Chop the code off the message */
return;
}
in that case, *its* custom messages will have been used above. */
smtp_notquit_exit(US"acl-drop", NULL, NULL);
+
+/* An overenthusiastic fail2ban/iptables implimentation has been seen to result
+in the TCP conn staying open, and retrying, despite this process exiting. A
+malicious client could possibly do the same, tying up server netowrking
+resources. Close the socket explicitly to try to avoid that (there's a note in
+the Linux socket(7) manpage, SO_LINGER para, to the effect that exim() without
+close() results in the socket always lingering). */
+
+(void) poll_one_fd(fileno(smtp_in), POLLIN, 200);
+DEBUG(D_any) debug_printf_indent("SMTP(close)>>\n");
+(void) fclose(smtp_in);
+(void) fclose(smtp_out);
+
return 2;
}
static int
-smtp_in_auth(auth_instance *au, uschar ** s, uschar ** ss)
+smtp_in_auth(auth_instance *au, uschar ** smtp_resp, uschar ** errmsg)
{
const uschar *set_id = NULL;
int rc;
+/* Set up globals for error messages */
+
+authenticator_name = au->name;
+driver_srcfile = au->srcfile;
+driver_srcline = au->srcline;
+
/* 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>
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> */
+driver_srcfile = authenticator_name = NULL; driver_srcline = 0;
/* 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
received_protocol =
(sender_host_address ? protocols : protocols_local)
[pextend + pauthed + (tls_in.active.sock >= 0 ? pcrpted:0)];
- *s = *ss = US"235 Authentication succeeded";
+ *smtp_resp = *errmsg = US"235 Authentication succeeded";
authenticated_by = au;
break;
}
case DEFER:
if (set_id) authenticated_fail_id = string_copy_perm(set_id, TRUE);
- *s = string_sprintf("435 Unable to authenticate at present%s",
+ *smtp_resp = string_sprintf("435 Unable to authenticate at present%s",
auth_defer_user_msg);
- *ss = string_sprintf("435 Unable to authenticate at present%s: %s",
+ *errmsg = 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";
+ *smtp_resp = *errmsg = US"501 Invalid base64 data";
break;
case CANCELLED:
- *s = *ss = US"501 Authentication cancelled";
+ *smtp_resp = *errmsg = US"501 Authentication cancelled";
break;
case UNEXPECTED:
- *s = *ss = US"553 Initial data not expected";
+ *smtp_resp = *errmsg = 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);
+ *smtp_resp = US"535 Incorrect authentication data";
+ *errmsg = 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 "
+ *smtp_resp = US"435 Internal error";
+ *errmsg = string_sprintf("435 Internal error%s: return %d from authentication "
"check", set_id, rc);
break;
}
/* Pause, hoping client will FIN first so that they get the TIME_WAIT.
The socket should become readble (though with no data) */
- {
- int fd = fileno(smtp_in);
- fd_set fds;
- struct timeval t_limit = {.tv_sec = 0, .tv_usec = 200*1000};
-
- FD_ZERO(&fds);
- FD_SET(fd, &fds);
- (void) select(fd + 1, (SELECT_ARG2_TYPE *)&fds, NULL, NULL, &t_limit);
- }
-#endif /*!DAEMON_CLOSE_NOWAIT*/
+(void) poll_one_fd(fileno(smtp_in), POLLIN, 200);
+#endif /*!SERVERSIDE_CLOSE_NOWAIT*/
}
incomplete_transaction_log(US"RSET");
smtp_printf("250 Reset OK\r\n", FALSE);
cmd_list[CMD_LIST_RSET].is_mail_cmd = FALSE;
+if (chunking_state > CHUNKING_OFFERED)
+ chunking_state = CHUNKING_OFFERED;
}
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"); }
+ {
+ DEBUG(D_auth) debug_printf("tls auth not succeeded\n");
+#ifndef DISABLE_EVENT
+ {
+ uschar * save_name = sender_host_authenticated, * logmsg;
+ sender_host_authenticated = au->name;
+ if ((logmsg = event_raise(event_action, US"auth:fail", s, NULL)))
+ log_write(0, LOG_MAIN, "%s", logmsg);
+ sender_host_authenticated = save_name;
+ }
+#endif
+ }
}
break;
}
{
auth_instance * au;
+ uschar * smtp_resp, * errmsg;
+
for (au = auths; au; au = au->next)
if (strcmpic(s, au->public_name) == 0 && au->server &&
(au->advertised || f.allow_auth_unadvertised))
if (au)
{
- c = smtp_in_auth(au, &s, &ss);
+ int rc = smtp_in_auth(au, &smtp_resp, &errmsg);
- 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);
+ smtp_printf("%s\r\n", FALSE, smtp_resp);
+ if (rc != OK)
+ {
+ uschar * logmsg = NULL;
+#ifndef DISABLE_EVENT
+ {uschar * save_name = sender_host_authenticated;
+ sender_host_authenticated = au->name;
+ logmsg = event_raise(event_action, US"auth:fail", smtp_resp, NULL);
+ sender_host_authenticated = save_name;
+ }
+#endif
+ if (logmsg)
+ log_write(0, LOG_MAIN|LOG_REJECT, "%s", logmsg);
+ else
+ log_write(0, LOG_MAIN|LOG_REJECT, "%s authenticator failed for %s: %s",
+ au->name, host_and_ident(FALSE), errmsg);
+ }
}
else
done = synprot_error(L_smtp_protocol_error, 504, NULL,
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_get_tainted(24, GET_TAINTED);
g = string_fmt_append(g, "%.3s %s Hello %s%s%s",
smtp_code,
smtp_active_hostname,
else
{
- char *ss;
+ 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);
#endif
(void) fwrite(g->s, 1, g->ptr, smtp_out);
- 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);
- }
+ DEBUG(D_receive) for (const uschar * t, * s = string_from_gstring(g);
+ s && (t = Ustrchr(s, '\r'));
+ s = t + 2) /* \r\n */
+ debug_printf("%s %.*s\n",
+ s == g->s ? "SMTP>>" : " ",
+ (int)(t - s), s);
fl.helo_seen = TRUE;
/* Reset the protocol and the state, abandoning any previous message. */
count this as a protocol error. Reset was_rej_mail so that further RCPTs
get the same treatment. */
- if (sender_address == NULL)
+ if (!sender_address)
{
if (f.smtp_in_pipelining_advertised && last_was_rej_mail)
{
/* Check for an operand */
- if (smtp_cmd_data[0] == 0)
+ if (!smtp_cmd_data[0])
{
done = synprot_error(L_smtp_syntax_error, 501, NULL,
US"RCPT must have an address operand");
#endif
if (!discarded && recipients_count <= 0)
{
- if (fl.rcpt_smtp_response_same && rcpt_smtp_response != NULL)
+ if (fl.rcpt_smtp_response_same && rcpt_smtp_response)
{
uschar *code = US"503";
int len = Ustrlen(rcpt_smtp_response);
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)
+ if (!acl_smtp_predata && cutthrough.cctx.sock < 0)
rc = OK;
else
{
Pipelining sync checks will normally have protected us too, unless disabled
by configuration. */
- if (receive_smtp_buffered())
+ if (receive_hasc())
{
DEBUG(D_any)
debug_printf("Non-empty input buffer after STARTTLS; naive attack?\n");
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);
+ FALSE, US"ETRN processing", &error);
deliver_domain = NULL;
if (!rc)
{
{
DEBUG(D_exec) debug_print_argv(argv);
exim_nullstd(); /* Ensure std{in,out,err} exist */
+ /* argv[0] should be untainted, from child_exec_exim() */
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));
COMMAND_LOOP:
last_was_rej_mail = was_rej_mail; /* Remember some last commands for */
last_was_rcpt = was_rcpt; /* protocol error handling */
- continue;
}
return done - 2; /* Convert yield values */
git://git.exim.org / exim.git / blobdiff