Merge native DKIM support (from DEVEL_PDKIM)

[exim.git] / src / src / smtp_in.c

diff --git a/src/src/smtp_in.c b/src/src/smtp_in.c
index 04bffd017e345ab103ab31e97cee711b5e166569..b9d92d63131c427f4f3d17c3b3a2eb0605736d6b 100644 (file)
--- a/src/src/smtp_in.c
+++ b/src/src/smtp_in.c
@@ -1,10 +1,10 @@
-/* $Cambridge: exim/src/src/smtp_in.c,v 1.30 2006/02/10 14:25:43 ph10 Exp $ */
+/* $Cambridge: exim/src/src/smtp_in.c,v 1.64 2009/06/10 07:34:04 tom Exp $ */

 
 /*************************************************
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 
 
 /*************************************************
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 

-/* Copyright (c) University of Cambridge 1995 - 2006 */
+/* Copyright (c) University of Cambridge 1995 - 2007 */

 /* See the file NOTICE for conditions of use and distribution. */
 
 /* Functions for handling an incoming SMTP call. */
 /* See the file NOTICE for conditions of use and distribution. */
 
 /* Functions for handling an incoming SMTP call. */


@@ -96,6 +96,13 @@ enum {
   TOO_MANY_NONMAIL_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          *
 
 /*************************************************
 *                Local static variables          *


@@ -113,12 +120,19 @@ static BOOL helo_seen;
 static BOOL helo_accept_junk;
 static BOOL count_nonmail;
 static BOOL pipelining_advertised;
 static BOOL helo_accept_junk;
 static BOOL count_nonmail;
 static BOOL pipelining_advertised;

+static BOOL rcpt_smtp_response_same;
+static BOOL rcpt_in_progress;

 static int  nonmail_command_count;
 static int  nonmail_command_count;

+static BOOL smtp_exit_function_called = 0;

 static int  synprot_error_count;
 static int  unknown_command_count;
 static int  sync_cmd_limit;
 static int  smtp_write_error = 0;
 
 static int  synprot_error_count;
 static int  unknown_command_count;
 static int  sync_cmd_limit;
 static int  smtp_write_error = 0;
 

+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
 setup, to allow one of each between messages that is not counted as a nonmail
 /* 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
 setup, to allow one of each between messages that is not counted as a nonmail


@@ -165,6 +179,15 @@ static smtp_cmd_list *cmd_list_end =
 #define CMD_LIST_AUTH      3
 #define CMD_LIST_STARTTLS  4
 
 #define CMD_LIST_AUTH      3
 #define CMD_LIST_STARTTLS  4
 

+/* 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"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[] = {
   US"local-smtp",        /* HELO */
   US"local-smtps",       /* The rare case EHLO->STARTTLS->HELO */
 static uschar *protocols[] = {
   US"local-smtp",        /* HELO */
   US"local-smtps",       /* The rare case EHLO->STARTTLS->HELO */


@@ -241,6 +264,9 @@ if (smtp_inptr >= smtp_inend)
     else smtp_had_eof = 1;
     return EOF;
     }
     else smtp_had_eof = 1;
     return EOF;
     }

+#ifndef DISABLE_DKIM
+  dkim_exim_verify_feed(smtp_inbuffer, rc);
+#endif

   smtp_inend = smtp_inbuffer + rc;
   smtp_inptr = smtp_inbuffer;
   }
   smtp_inend = smtp_inbuffer + rc;
   smtp_inptr = smtp_inbuffer;
   }


@@ -311,6 +337,23 @@ 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     *
 
 /*************************************************
 *     Write formatted string to SMTP channel     *


@@ -336,36 +379,69 @@ smtp_printf(char *format, ...)
 {
 va_list ap;
 
 {
 va_list ap;
 

+va_start(ap, format);
+smtp_vprintf(format, 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.
+
+Note also that repeated calls to va_start()/va_end() pairs is claimed to be
+non-portable; meanwhile, va_copy() is also non-portable in that it's C99, so
+we end up needing OS support to define it for us. */
+
+void
+smtp_vprintf(char *format, va_list ap)
+{
+va_list ap_d;
+

 DEBUG(D_receive)
   {
 DEBUG(D_receive)
   {

-  va_start(ap, format);
-  (void) string_vformat(big_buffer, big_buffer_size, format, ap);
+  uschar *cr, *end;
+  va_copy(ap_d, ap);
+  (void) string_vformat(big_buffer, big_buffer_size, format, ap_d);
+  end = big_buffer + Ustrlen(big_buffer);
+  while ((cr = Ustrchr(big_buffer, '\r')) != NULL)   /* lose CRs */
+    memmove(cr, cr + 1, (end--) - cr);

   debug_printf("SMTP>> %s", big_buffer);
   }
 
   debug_printf("SMTP>> %s", big_buffer);
   }
 

-va_start(ap, format);
+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 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(). */
+
+if (rcpt_in_progress)
+  {
+  if (rcpt_smtp_response == NULL)
+    rcpt_smtp_response = string_copy(big_buffer);
+  else if (rcpt_smtp_response_same &&
+           Ustrcmp(rcpt_smtp_response, big_buffer) != 0)
+    rcpt_smtp_response_same = FALSE;
+  rcpt_in_progress = FALSE;
+  }

 
 

-/* If in a TLS session we have to format the string, and then write it using a
-TLS function. */
+/* Now write the string */

 
 #ifdef SUPPORT_TLS
 if (tls_active >= 0)
   {
 
 #ifdef SUPPORT_TLS
 if (tls_active >= 0)
   {

-  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;
   }
 else
 #endif
 
   if (tls_write(big_buffer, Ustrlen(big_buffer)) < 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", big_buffer) < 0) smtp_write_error = -1;

 }
 
 
 }
 
 


@@ -413,9 +489,8 @@ log_write(L_lost_incoming_connection,
           host_and_ident(FALSE));
 if (smtp_batched_input)
   moan_smtp_batch(NULL, "421 SMTP command timeout");  /* Does not return */
           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();
+smtp_notquit_exit(US"command-timeout", US"421",
+  US"%s: SMTP command timeout - closing connection", smtp_active_hostname);

 exim_exit(EXIT_FAILURE);
 }
 
 exim_exit(EXIT_FAILURE);
 }
 


@@ -438,13 +513,14 @@ 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 */
 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);
+smtp_notquit_exit(US"signal-exit", US"421",
+  US"%s: Service not available - closing connection", smtp_active_hostname);

 exim_exit(EXIT_FAILURE);
 }
 
 
 
 exim_exit(EXIT_FAILURE);
 }
 
 
 

+

 /*************************************************
 *           Read one command line                *
 *************************************************/
 /*************************************************
 *           Read one command line                *
 *************************************************/


@@ -518,7 +594,10 @@ if required. */
 
 for (p = cmd_list; p < cmd_list_end; p++)
   {
 
 for (p = cmd_list; p < cmd_list_end; p++)
   {

-  if (strncmpic(smtp_cmd_buffer, US p->name, p->len) == 0)
+  if (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 */
     {
     if (smtp_inptr < smtp_inend &&                     /* Outstanding input */
         p->cmd < sync_cmd_limit &&                     /* Command should sync */


@@ -528,11 +607,16 @@ for (p = cmd_list; p < cmd_list_end; p++)
         !sender_host_notsocket)                        /* Really is a socket */
       return BADSYN_CMD;
 
         !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_cmd_argument = smtp_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
 
     /* 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


@@ -550,11 +634,10 @@ for (p = cmd_list; p < cmd_list_end; p++)
         return TOO_MANY_NONMAIL_CMD;
       }
 
         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_cmd_argument)) smtp_cmd_argument++;
-    return (p->has_arg || *smtp_cmd_argument == 0)? p->cmd : BADARG_CMD;
+    return (p->has_arg || *smtp_cmd_data == 0)? p->cmd : BADARG_CMD;

     }
   }
 
     }
   }
 


@@ -572,6 +655,60 @@ return OTHER_CMD;
 
 
 
 
 
 

+/*************************************************
+*          Recheck synchronization               *
+*************************************************/
+
+/* Synchronization checks can never be perfect because a packet may be on its
+way but not arrived when the check is done. Such checks can in any case only be
+done when TLS is not in use. 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
+check_sync(void)
+{
+int fd, rc;
+fd_set fds;
+struct timeval tzero;
+
+if (!smtp_enforce_sync || sender_host_address == NULL ||
+    sender_host_notsocket || tls_active >= 0)
+  return TRUE;
+
+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();
+if (rc < 0) return TRUE;      /* End of file or error */
+
+smtp_ungetc(rc);
+rc = smtp_inend - smtp_inptr;
+if (rc > 150) rc = 150;
+smtp_inptr[rc] = 0;
+return FALSE;
+}
+
+
+

 /*************************************************
 *          Forced closedown of call              *
 *************************************************/
 /*************************************************
 *          Forced closedown of call              *
 *************************************************/


@@ -583,7 +720,9 @@ phase, sends the reply string, and gives an error to all subsequent commands
 except QUIT. The existence of an SMTP call is detected by the non-NULLness of
 smtp_in.
 
 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
 */
 
 Returns:    nothing
 */
 


@@ -626,6 +765,8 @@ for (;;)
 
 /* This function is called when logging information about an SMTP connection.
 It sets up appropriate source information, depending on the type of connection.
 
 /* 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
 
 Argument:    none
 Returns:     a string describing the connection


@@ -634,21 +775,93 @@ Returns:     a string describing the connection
 uschar *
 smtp_get_connection_info(void)
 {
 uschar *
 smtp_get_connection_info(void)
 {

+uschar *hostname = (sender_fullhost == NULL)?
+  sender_host_address : sender_fullhost;
+

 if (host_checking)
 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)
   return string_sprintf("SMTP connection from %s", sender_ident);
 
 if (is_inetd)
 
 if (sender_host_unknown || 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);
+  return string_sprintf("SMTP connection from %s (via inetd)", hostname);

 
 if ((log_extra_selector & LX_incoming_interface) != 0 &&
      interface_address != NULL)
 
 if ((log_extra_selector & LX_incoming_interface) != 0 &&
      interface_address != NULL)

-  return string_sprintf("SMTP connection from %s I=[%s]:%d", sender_fullhost,
+  return string_sprintf("SMTP connection from %s I=[%s]:%d", hostname,

     interface_address, interface_port);
 
     interface_address, interface_port);
 

-return string_sprintf("SMTP connection from %s", sender_fullhost);
+return string_sprintf("SMTP connection from %s", hostname);
+}
+
+
+
+/*************************************************
+*      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)
+{
+int size, ptr, i;
+uschar *s, *sep;
+
+if (smtp_mailcmd_count > 0 || (log_extra_selector & LX_smtp_no_mail) == 0)
+  return;
+
+s = NULL;
+size = ptr = 0;
+
+if (sender_host_authenticated != NULL)
+  {
+  s = string_append(s, &size, &ptr, 2, US" A=", sender_host_authenticated);
+  if (authenticated_id != NULL)
+    s = string_append(s, &size, &ptr, 2, US":", authenticated_id);
+  }
+
+#ifdef SUPPORT_TLS
+if ((log_extra_selector & LX_tls_cipher) != 0 && tls_cipher != NULL)
+  s = string_append(s, &size, &ptr, 2, US" X=", tls_cipher);
+if ((log_extra_selector & LX_tls_certificate_verified) != 0 &&
+     tls_cipher != NULL)
+  s = string_append(s, &size, &ptr, 2, US" CV=",
+    tls_certificate_verified? "yes":"no");
+if ((log_extra_selector & LX_tls_peerdn) != 0 && tls_peerdn != NULL)
+  s = string_append(s, &size, &ptr, 3, US" DN=\"",
+    string_printing(tls_peerdn), US"\"");
+#endif
+
+sep = (smtp_connection_had[SMTP_HBUFF_SIZE-1] != SCH_NONE)?
+  US" C=..." : US" C=";
+for (i = smtp_ch_index; i < SMTP_HBUFF_SIZE; i++)
+  {
+  if (smtp_connection_had[i] != SCH_NONE)
+    {
+    s = string_append(s, &size, &ptr, 2, sep,
+      smtp_names[smtp_connection_had[i]]);
+    sep = US",";
+    }
+  }
+
+for (i = 0; i < smtp_ch_index; i++)
+  {
+  s = string_append(s, &size, &ptr, 2, sep, smtp_names[smtp_connection_had[i]]);
+  sep = US",";
+  }
+
+if (s != NULL) s[ptr] = 0; else s = US"";
+log_write(0, LOG_MAIN, "no MAIL in SMTP connection from %s D=%s%s",
+  host_and_ident(FALSE),
+  readconf_printtime(time(NULL) - smtp_connection_start), s);

 }
 
 
 }
 
 


@@ -742,7 +955,7 @@ return yield;
 *         Extract SMTP command option            *
 *************************************************/
 
 *         Extract SMTP command option            *
 *************************************************/
 

-/* This function picks the next option setting off the end of smtp_cmd_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.
 
 is called for MAIL FROM and RCPT TO commands, to pick off the optional ESMTP
 things that can appear there.
 


@@ -757,11 +970,11 @@ static BOOL
 extract_option(uschar **name, uschar **value)
 {
 uschar *n;
 extract_option(uschar **name, uschar **value)
 {
 uschar *n;

-uschar *v = smtp_cmd_argument + Ustrlen(smtp_cmd_argument) -1;
+uschar *v = smtp_cmd_data + Ustrlen(smtp_cmd_data) - 1;

 while (isspace(*v)) v--;
 v[1] = 0;
 
 while (isspace(*v)) v--;
 v[1] = 0;
 

-while (v > smtp_cmd_argument && *v != '=' && !isspace(*v)) v--;
+while (v > smtp_cmd_data && *v != '=' && !isspace(*v)) v--;

 if (*v != '=') return FALSE;
 
 n = v;
 if (*v != '=') return FALSE;
 
 n = v;


@@ -780,8 +993,6 @@ return TRUE;
 
 
 
 
 
 

-
-

 /*************************************************
 *         Reset for new message                  *
 *************************************************/
 /*************************************************
 *         Reset for new message                  *
 *************************************************/


@@ -796,16 +1007,19 @@ Returns:    nothing
 static void
 smtp_reset(void *reset_point)
 {
 static 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;
 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;
+acl_added_headers = NULL;

 queue_only_policy = FALSE;
 queue_only_policy = FALSE;

+rcpt_smtp_response = NULL;
+rcpt_smtp_response_same = TRUE;
+rcpt_in_progress = FALSE;

 deliver_freeze = FALSE;                              /* Can be set by ACL */
 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 */
 fake_response = OK;                                  /* Can be set by ACL */
 #ifdef WITH_CONTENT_SCAN
 no_mbox_unspool = FALSE;                             /* Can be set by ACL */


@@ -826,8 +1040,10 @@ authenticated_sender = NULL;
 bmi_run = 0;
 bmi_verdicts = NULL;
 #endif
 bmi_run = 0;
 bmi_verdicts = NULL;
 #endif

-#ifdef EXPERIMENTAL_DOMAINKEYS
-dk_do_verify = 0;
+#ifndef DISABLE_DKIM
+dkim_signing_domains = NULL;
+dkim_disable_verify = FALSE;
+dkim_collect_input = FALSE;

 #endif
 #ifdef EXPERIMENTAL_SPF
 spf_header_comment = NULL;
 #endif
 #ifdef EXPERIMENTAL_SPF
 spf_header_comment = NULL;


@@ -841,9 +1057,9 @@ sender_rate = sender_rate_limit = sender_rate_period = NULL;
 ratelimiters_mail = NULL;           /* Updated by ratelimit ACL condition */
                    /* Note that ratelimiters_conn persists across resets. */
 
 ratelimiters_mail = NULL;           /* Updated by ratelimit ACL condition */
                    /* Note that ratelimiters_conn persists across resets. */
 

-/* The message variables follow the connection variables. */
+/* Reset message ACL variables */

 
 

-for (i = 0; i < ACL_MVARS; i++) acl_var[ACL_CVARS + i] = NULL;
+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
 
 /* 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


@@ -863,7 +1079,7 @@ if (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
 
 /* 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 != NULL)
   {


@@ -927,7 +1143,7 @@ while (done <= 0)
     case HELO_CMD:
     case EHLO_CMD:
 
     case HELO_CMD:
     case EHLO_CMD:
 

-    check_helo(smtp_cmd_argument);
+    check_helo(smtp_cmd_data);

     /* Fall through */
 
     case RSET_CMD:
     /* Fall through */
 
     case RSET_CMD:


@@ -947,7 +1163,7 @@ while (done <= 0)
       /* The function moan_smtp_batch() does not return. */
       moan_smtp_batch(smtp_cmd_buffer, "503 Sender already given");
 
       /* The function moan_smtp_batch() does not return. */
       moan_smtp_batch(smtp_cmd_buffer, "503 Sender already given");
 

-    if (smtp_cmd_argument[0] == 0)
+    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");
 
       /* The function moan_smtp_batch() does not return. */
       moan_smtp_batch(smtp_cmd_buffer, "501 MAIL FROM must have an address operand");
 


@@ -958,8 +1174,8 @@ while (done <= 0)
     /* Apply SMTP rewrite */
 
     raw_sender = ((rewrite_existflags & rewrite_smtp) != 0)?
     /* Apply SMTP rewrite */
 
     raw_sender = ((rewrite_existflags & rewrite_smtp) != 0)?

-      rewrite_one(smtp_cmd_argument, rewrite_smtp|rewrite_smtp_sender, NULL, FALSE,
-        US"", global_rewrite_rules) : smtp_cmd_argument;
+      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 */
 


@@ -1002,7 +1218,7 @@ while (done <= 0)
       /* The function moan_smtp_batch() does not return. */
       moan_smtp_batch(smtp_cmd_buffer, "503 No sender yet given");
 
       /* The function moan_smtp_batch() does not return. */
       moan_smtp_batch(smtp_cmd_buffer, "503 No sender yet given");
 

-    if (smtp_cmd_argument[0] == 0)
+    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");
 
       /* The function moan_smtp_batch() does not return. */
       moan_smtp_batch(smtp_cmd_buffer, "501 RCPT TO must have an address operand");
 


@@ -1017,8 +1233,8 @@ while (done <= 0)
     recipient address */
 
     recipient = ((rewrite_existflags & rewrite_smtp) != 0)?
     recipient address */
 
     recipient = ((rewrite_existflags & rewrite_smtp) != 0)?

-      rewrite_one(smtp_cmd_argument, rewrite_smtp, NULL, FALSE, US"",
-        global_rewrite_rules) : smtp_cmd_argument;
+      rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"",
+        global_rewrite_rules) : smtp_cmd_data;

 
     /* rfc821_domains = TRUE; << no longer needed */
     recipient = parse_extract_address(recipient, &errmess, &start, &end,
 
     /* rfc821_domains = TRUE; << no longer needed */
     recipient = parse_extract_address(recipient, &errmess, &start, &end,


@@ -1130,22 +1346,35 @@ BOOL
 smtp_start_session(void)
 {
 int size = 256;
 smtp_start_session(void)
 {
 int size = 256;

-int i, ptr;
+int ptr, esclen;
+uschar *user_msg, *log_msg;
+uschar *code, *esc;

 uschar *p, *s, *ss;
 
 uschar *p, *s, *ss;
 

+smtp_connection_start = time(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;
 /* Default values for certain variables */
 
 helo_seen = esmtp = 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;
 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;

+pipelining_enable = TRUE;

 sync_cmd_limit = NON_SYNC_CMD_NON_PIPELINING;
 sync_cmd_limit = NON_SYNC_CMD_NON_PIPELINING;

+smtp_exit_function_called = FALSE;    /* For avoiding loop in not-quit exit */

 
 memset(sender_host_cache, 0, sizeof(sender_host_cache));
 
 
 memset(sender_host_cache, 0, sizeof(sender_host_cache));
 

-sender_host_authenticated = NULL;
+/* If receiving by -bs from a trusted user, or testing with -bh, we allow
+authentication settings from -oMaa to remain in force. */
+
+if (!host_checking && !sender_host_notsocket) sender_host_authenticated = NULL;

 authenticated_by = NULL;
 
 #ifdef SUPPORT_TLS
 authenticated_by = NULL;
 
 #ifdef SUPPORT_TLS


@@ -1155,14 +1384,15 @@ tls_advertised = FALSE;
 
 /* Reset ACL connection variables */
 
 
 /* Reset ACL connection variables */
 

-for (i = 0; i < ACL_CVARS; i++) acl_var[i] = NULL;
+acl_var_c = NULL;

 
 

-/* Allow for trailing 0 in the command buffer. */
+/* Allow for trailing 0 in the command and data buffers. */

 
 

-smtp_cmd_buffer = (uschar *)malloc(smtp_cmd_buffer_size + 1);
+smtp_cmd_buffer = (uschar *)malloc(2*smtp_cmd_buffer_size + 2);

 if (smtp_cmd_buffer == NULL)
   log_write(0, LOG_MAIN|LOG_PANIC_DIE,
     "malloc() failed for SMTP command buffer");
 if (smtp_cmd_buffer == NULL)
   log_write(0, LOG_MAIN|LOG_PANIC_DIE,
     "malloc() failed for SMTP command buffer");

+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. */
 
 /* For batched input, the protocol setting can be overridden from the
 command line by a trusted caller. */


@@ -1189,13 +1419,14 @@ receive_getc = smtp_getc;
 receive_ungetc = smtp_ungetc;
 receive_feof = smtp_feof;
 receive_ferror = smtp_ferror;
 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 */
 
 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 != NULL)

   {
   if (thismessage_size_limit == -1)
     log_write(0, LOG_MAIN|LOG_PANIC, "unable to expand message_size_limit: "
   {
   if (thismessage_size_limit == -1)
     log_write(0, LOG_MAIN|LOG_PANIC, "unable to expand message_size_limit: "


@@ -1434,7 +1665,9 @@ if (!sender_host_unknown)
   smtps port for use with older style SSL MTAs. */
 
   #ifdef SUPPORT_TLS
   smtps port for use with older style SSL MTAs. */
 
   #ifdef SUPPORT_TLS

-  if (tls_on_connect && tls_server_start(tls_require_ciphers) != OK)
+  if (tls_on_connect &&
+      tls_server_start(tls_require_ciphers,
+        gnutls_require_mac, gnutls_require_kx, gnutls_require_proto) != OK)

     return FALSE;
   #endif
 
     return FALSE;
   #endif
 


@@ -1448,35 +1681,56 @@ if (!sender_host_unknown)
     return 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
 
   #ifdef USE_TCP_WRAPPERS

+  errno = 0;

   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))
     {
   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))
     {

-    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");
+      }
+    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");
+      }

     return FALSE;
     }
   #endif
 
     return FALSE;
     }
   #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 &&
 
   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",
     {
     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);
         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);


@@ -1536,10 +1790,10 @@ if (smtp_batched_input) return TRUE;
 
 /* Run the ACL if it exists */
 
 
 /* Run the ACL if it exists */
 

+user_msg = NULL;

 if (acl_smtp_connect != NULL)
   {
   int rc;
 if (acl_smtp_connect != NULL)
   {
   int rc;

-  uschar *user_msg, *log_msg;

   rc = acl_check(ACL_WHERE_CONNECT, NULL, acl_smtp_connect, &user_msg,
     &log_msg);
   if (rc != OK)
   rc = acl_check(ACL_WHERE_CONNECT, NULL, acl_smtp_connect, &user_msg,
     &log_msg);
   if (rc != OK)


@@ -1552,10 +1806,28 @@ if (acl_smtp_connect != NULL)
 /* Output the initial message for a two-way SMTP connection. It may contain
 newlines, which then cause a multi-line response to be given. */
 
 /* 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 == NULL)
+  {
+  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);
+  }
+else
+  {
+  int codelen = 3;
+  s = user_msg;
+  smtp_message_code(&code, &codelen, &s, NULL);
+  if (codelen > 4)
+    {
+    esc = code + 4;
+    esclen = codelen - 4;
+    }
+  }

 
 /* Remove any terminating newlines; might as well remove trailing space too */
 
 
 /* Remove any terminating newlines; might as well remove trailing space too */
 


@@ -1580,16 +1852,18 @@ do       /* At least once, in case we have an empty string */
   {
   int len;
   uschar *linebreak = Ustrchr(p, '\n');
   {
   int len;
   uschar *linebreak = Ustrchr(p, '\n');

+  ss = string_cat(ss, &size, &ptr, code, 3);

   if (linebreak == NULL)
     {
     len = Ustrlen(p);
   if (linebreak == NULL)
     {
     len = Ustrlen(p);

-    ss = string_cat(ss, &size, &ptr, US"220 ", 4);
+    ss = string_cat(ss, &size, &ptr, US" ", 1);

     }
   else
     {
     len = linebreak - p;
     }
   else
     {
     len = linebreak - p;

-    ss = string_cat(ss, &size, &ptr, US"220-", 4);
+    ss = string_cat(ss, &size, &ptr, US"-", 1);

     }
     }

+  ss = string_cat(ss, &size, &ptr, esc, esclen);

   ss = string_cat(ss, &size, &ptr, p, len);
   ss = string_cat(ss, &size, &ptr, US"\r\n", 2);
   p += len;
   ss = string_cat(ss, &size, &ptr, p, len);
   ss = string_cat(ss, &size, &ptr, US"\r\n", 2);
   p += len;


@@ -1602,30 +1876,14 @@ ss[ptr] = 0;  /* string_cat leaves room for this */
 /* Before we write the banner, check that there is no input pending, unless
 this synchronisation check is disabled. */
 
 /* 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)
+if (!check_sync())

   {
   {

-  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)
-    {
-    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;
-      }
-    }
+  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_inptr));
+  smtp_printf("554 SMTP synchronization error\r\n");
+  return FALSE;

   }
 
 /* Now output the banner */
   }
 
 /* Now output the banner */


@@ -1735,7 +1993,8 @@ responses. If no_multiline_responses is TRUE (it can be set from an ACL), we
 output nothing for non-final calls, and only the first line for anything else.
 
 Arguments:
 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
 
   final         FALSE if the last line isn't the final line
   msg           message text, possibly containing newlines
 


@@ -1743,26 +2002,54 @@ Returns:        nothing
 */
 
 void
 */
 
 void

-smtp_respond(int code, BOOL final, uschar *msg)
+smtp_respond(uschar* code, int codelen, BOOL final, uschar *msg)

 {
 {

+int esclen = 0;
+uschar *esc = US"";
+

 if (!final && no_multiline_responses) return;
 
 if (!final && 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 (rcpt_in_progress)
+  {
+  if (rcpt_smtp_response == NULL)
+    rcpt_smtp_response = string_copy(msg);
+  else if (rcpt_smtp_response_same &&
+           Ustrcmp(rcpt_smtp_response, msg) != 0)
+    rcpt_smtp_response_same = FALSE;
+  rcpt_in_progress = FALSE;
+  }
+
+/* Not output the message, splitting it up into multiple lines if necessary. */
+

 for (;;)
   {
   uschar *nl = Ustrchr(msg, '\n');
   if (nl == NULL)
     {
 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", code, final? ' ':'-', esclen, esc, msg);

     return;
     }
   else if (nl[1] == 0 || no_multiline_responses)
     {
     return;
     }
   else if (nl[1] == 0 || no_multiline_responses)
     {

-    smtp_printf("%d%c%.*s\r\n", code, final? ' ':'-', (int)(nl - msg), msg);
+    smtp_printf("%.3s%c%.*s%.*s\r\n", code, final? ' ':'-', esclen, esc,
+      (int)(nl - msg), msg);

     return;
     }
   else
     {
     return;
     }
   else
     {

-    smtp_printf("%d-%.*s\r\n", code, (int)(nl - msg), msg);
+    smtp_printf("%.3s-%.*s%.*s\r\n", code, esclen, esc, (int)(nl - msg), msg);

     msg = nl + 1;
     while (isspace(*msg)) msg++;
     }
     msg = nl + 1;
     while (isspace(*msg)) msg++;
     }


@@ -1772,6 +2059,65 @@ for (;;)
 
 
 
 
 
 

+/*************************************************
+*            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
+
+Returns:        nothing
+*/
+
+void
+smtp_message_code(uschar **code, int *codelen, uschar **msg, uschar **log_msg)
+{
+int n;
+int ovector[3];
+
+if (msg == NULL || *msg == NULL) return;
+
+n = pcre_exec(regex_smtp_code, NULL, CS *msg, Ustrlen(*msg), 0,
+  PCRE_EOPT, ovector, sizeof(ovector)/sizeof(int));
+if (n < 0) return;
+
+if ((*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                *
 *************************************************/
 /*************************************************
 *           Handle an ACL failure                *
 *************************************************/


@@ -1782,13 +2128,18 @@ logging the incident, and sets up the error response. A message containing
 newlines is turned into a multiline SMTP response, but for logging, only the
 first line is used.
 
 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. 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
 
 Arguments:
   where      where the ACL was called from


@@ -1805,8 +2156,9 @@ Returns:     0 in most cases
 int
 smtp_handle_acl_fail(int where, int rc, uschar *user_msg, uschar *log_msg)
 {
 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;
 BOOL drop = rc == FAIL_DROP;

+int codelen = 3;
+uschar *smtp_code;

 uschar *lognl;
 uschar *sender_info = US"";
 uschar *what =
 uschar *lognl;
 uschar *sender_info = US"";
 uschar *what =


@@ -1815,12 +2167,17 @@ uschar *what =
 #endif
   (where == ACL_WHERE_PREDATA)? US"DATA" :
   (where == ACL_WHERE_DATA)? US"after DATA" :
 #endif
   (where == ACL_WHERE_PREDATA)? US"DATA" :
   (where == ACL_WHERE_DATA)? US"after DATA" :

-  (smtp_cmd_argument == NULL)?
+  (smtp_cmd_data == NULL)?

     string_sprintf("%s in \"connect\" ACL", acl_wherenames[where]) :
     string_sprintf("%s in \"connect\" ACL", acl_wherenames[where]) :

-    string_sprintf("%s %s", acl_wherenames[where], smtp_cmd_argument);
+    string_sprintf("%s %s", acl_wherenames[where], smtp_cmd_data);

 
 if (drop) rc = FAIL;
 
 
 if (drop) rc = FAIL;
 

+/* Set the default SMTP code, and allow a user message to change it. */
+
+smtp_code = (rc != FAIL)? US"451" : acl_wherecodes[where];
+smtp_message_code(&smtp_code, &codelen, &user_msg, &log_msg);
+

 /* 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
 /* 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


@@ -1839,22 +2196,27 @@ if (where == ACL_WHERE_RCPT || where == ACL_WHERE_DATA || where == ACL_WHERE_MIM
 
 /* 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
 
 /* 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 &&
     !testflag(sender_verified_failed, af_sverify_told))
   {
 
 if (sender_verified_failed != NULL &&
     !testflag(sender_verified_failed, af_sverify_told))
   {

+  BOOL save_rcpt_in_progress = rcpt_in_progress;
+  rcpt_in_progress = FALSE;  /* So as not to treat these as the error */
+

   setflag(sender_verified_failed, af_sverify_told);
 
   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 || (log_extra_selector & LX_sender_verify_fail) != 0)
+    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)
 
   if (rc == FAIL && sender_verified_failed->user_message != NULL)

-    smtp_respond(code, FALSE, string_sprintf(
+    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"
         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"


@@ -1872,6 +2234,8 @@ if (sender_verified_failed != NULL &&
           "Verification failed for <%s>\n%s",
         sender_verified_failed->address,
         sender_verified_failed->user_message));
           "Verification failed for <%s>\n%s",
         sender_verified_failed->address,
         sender_verified_failed->user_message));

+
+  rcpt_in_progress = save_rcpt_in_progress;

   }
 
 /* Sort out text for logging */
   }
 
 /* Sort out text for logging */


@@ -1884,7 +2248,7 @@ if (lognl != NULL) *lognl = 0;
 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. */
 
 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)?
+if (rc == FAIL) smtp_respond(smtp_code, codelen, TRUE, (user_msg == NULL)?

   US"Administrative prohibition" : user_msg);
 
 /* Send temporary failure response to the command. Don't give any details,
   US"Administrative prohibition" : user_msg);
 
 /* Send temporary failure response to the command. Don't give any details,


@@ -1903,31 +2267,121 @@ else
         sender_verified_failed != NULL &&
         sender_verified_failed->message != NULL)
       {
         sender_verified_failed != NULL &&
         sender_verified_failed->message != NULL)
       {

-      smtp_respond(451, FALSE, sender_verified_failed->message);
+      smtp_respond(smtp_code, codelen, FALSE, sender_verified_failed->message);

       }
       }

-    smtp_respond(451, TRUE, user_msg);
+    smtp_respond(smtp_code, codelen, TRUE, user_msg);

     }
   else
     }
   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)
+  log_write(0, log_reject_target, "%s %s%srejected %s%s",
+    host_and_ident(TRUE),
+    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());
 
 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;
 }
 
 
 
 
 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 funtion, 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 acll */
+
+if (smtp_exit_function_called)
+  {
+  log_write(0, LOG_PANIC, "smtp_notquit_exit() called more than once (%s)",
+    reason);
+  return;
+  }
+smtp_exit_function_called = TRUE;
+
+/* Call the not-QUIT ACL, if there is one, unless no reason is given. */
+
+if (acl_smtp_notquit != NULL && reason != NULL)
+  {
+  smtp_notquit_reason = reason;
+  rc = acl_check(ACL_WHERE_NOTQUIT, NULL, acl_smtp_notquit, &user_msg,
+    &log_msg);
+  if (rc == ERROR)
+    log_write(0, LOG_MAIN|LOG_PANIC, "ACL for not-QUIT returned ERROR: %s",
+      log_msg);
+  }
+
+/* Write an SMTP response if we are expected to give one. As the default
+responses are all internal, they should always fit in the buffer, but code a
+warning, just in case. Note that string_vformat() still leaves a complete
+string, even if it is incomplete. */
+
+if (code != NULL && defaultrespond != NULL)
+  {
+  if (user_msg == NULL)
+    {
+    uschar buffer[128];
+    va_list ap;
+    va_start(ap, defaultrespond);
+    if (!string_vformat(buffer, sizeof(buffer), CS defaultrespond, ap))
+      log_write(0, LOG_MAIN|LOG_PANIC, "string too large in smtp_notquit_exit()");
+    smtp_printf("%s %s\r\n", code, buffer);
+    va_end(ap);
+    }
+  else
+    smtp_respond(code, 3, TRUE, user_msg);
+  mac_smtp_fflush();
+  }
+}
+
+
+
+

 /*************************************************
 *             Verify HELO argument               *
 *************************************************/
 /*************************************************
 *             Verify HELO argument               *
 *************************************************/


@@ -1960,6 +2414,16 @@ if (sender_helo_name == NULL)
   HDEBUG(D_receive) debug_printf("no EHLO/HELO command was issued\n");
   }
 
   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");
+  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,
 else if (sender_helo_name[0] == '[')
   {
   helo_verified = Ustrncmp(sender_helo_name+1, sender_host_address,


@@ -2025,7 +2489,7 @@ else
     h.next = NULL;
     HDEBUG(D_receive) debug_printf("getting IP address for %s\n",
       sender_helo_name);
     h.next = NULL;
     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_byname(&h, NULL, 0, NULL, TRUE);

     if (rc == HOST_FOUND || rc == HOST_FOUND_LOCAL)
       {
       host_item *hh = &h;
     if (rc == HOST_FOUND || rc == HOST_FOUND_LOCAL)
       {
       host_item *hh = &h;


@@ -2045,13 +2509,40 @@ else
     }
   }
 
     }
   }
 

-if (!helo_verified) helo_verify_failed = FALSE;  /* We've tried ... */
+if (!helo_verified) helo_verify_failed = TRUE;  /* We've tried ... */

 return yield;
 }
 
 
 
 
 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);
+smtp_respond(code, len, TRUE, user_msg);
+}
+
+
+
+

 /*************************************************
 *       Initialize for SMTP incoming message     *
 *************************************************/
 /*************************************************
 *       Initialize for SMTP incoming message     *
 *************************************************/


@@ -2122,7 +2613,8 @@ while (done <= 0)
   uschar *etrn_command;
   uschar *etrn_serialize_key;
   uschar *errmess;
   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 *recipient = NULL;
   uschar *hello = NULL;
   uschar *set_id = NULL;


@@ -2139,20 +2631,25 @@ while (done <= 0)
   switch(smtp_read_command(TRUE))
     {
     /* The AUTH command is not permitted to occur inside a transaction, and may
   switch(smtp_read_command(TRUE))
     {
     /* 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:
 
     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:

+    HAD(SCH_AUTH);

     authentication_failed = TRUE;
     cmd_list[CMD_LIST_AUTH].is_mail_cmd = FALSE;
 
     authentication_failed = TRUE;
     cmd_list[CMD_LIST_AUTH].is_mail_cmd = FALSE;
 

-    if (!auth_advertised)
+    if (!auth_advertised && !allow_auth_unadvertised)

       {
       done = synprot_error(L_smtp_protocol_error, 503, NULL,
         US"AUTH command used when not advertised");
       {
       done = synprot_error(L_smtp_protocol_error, 503, NULL,
         US"AUTH command used when not advertised");


@@ -2185,8 +2682,8 @@ while (done <= 0)
 
     /* Find the name of the requested authentication mechanism. */
 
 
     /* Find the name of the requested authentication mechanism. */
 

-    s = smtp_cmd_argument;
-    while ((c = *smtp_cmd_argument) != 0 && !isspace(c))
+    s = smtp_cmd_data;
+    while ((c = *smtp_cmd_data) != 0 && !isspace(c))

       {
       if (!isalnum(c) && c != '-' && c != '_')
         {
       {
       if (!isalnum(c) && c != '-' && c != '_')
         {


@@ -2194,25 +2691,26 @@ while (done <= 0)
           US"invalid character in authentication mechanism name");
         goto COMMAND_LOOP;
         }
           US"invalid character in authentication mechanism name");
         goto COMMAND_LOOP;
         }

-      smtp_cmd_argument++;
+      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 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_argument != 0)
+    if (*smtp_cmd_data != 0)

       {
       {

-      *smtp_cmd_argument++ = 0;
-      while (isspace(*smtp_cmd_argument)) smtp_cmd_argument++;
+      *smtp_cmd_data++ = 0;
+      while (isspace(*smtp_cmd_data)) smtp_cmd_data++;

       }
 
     /* Search for an authentication mechanism which is configured for use
       }
 
     /* Search for an authentication mechanism which is configured for use

-    as a server and which has been advertised. */
+    as a server and which has been advertised (unless, sigh, allow_auth_
+    unadvertised is set). */

 
     for (au = auths; au != NULL; au = au->next)
       {
       if (strcmpic(s, au->public_name) == 0 && au->server &&
 
     for (au = auths; au != NULL; au = au->next)
       {
       if (strcmpic(s, au->public_name) == 0 && au->server &&

-          au->advertised) break;
+          (au->advertised || allow_auth_unadvertised)) break;

       }
 
     if (au == NULL)
       }
 
     if (au == NULL)


@@ -2238,7 +2736,7 @@ while (done <= 0)
     expand_nmax = 0;
     expand_nlength[0] = 0;   /* $0 contains nothing */
 
     expand_nmax = 0;
     expand_nlength[0] = 0;   /* $0 contains nothing */
 

-    c = (au->info->servercode)(au, smtp_cmd_argument);
+    c = (au->info->servercode)(au, smtp_cmd_data);

     if (au->set_id != NULL) set_id = expand_string(au->set_id);
     expand_nmax = -1;        /* Reset numeric variables */
     for (i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL;   /* Reset $auth<n> */
     if (au->set_id != NULL) set_id = expand_string(au->set_id);
     expand_nmax = -1;        /* Reset numeric variables */
     for (i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL;   /* Reset $auth<n> */


@@ -2340,11 +2838,13 @@ while (done <= 0)
     it did the reset first. */
 
     case HELO_CMD:
     it did the reset first. */
 
     case HELO_CMD:

+    HAD(SCH_HELO);

     hello = US"HELO";
     esmtp = FALSE;
     goto HELO_EHLO;
 
     case EHLO_CMD:
     hello = US"HELO";
     esmtp = FALSE;
     goto HELO_EHLO;
 
     case EHLO_CMD:

+    HAD(SCH_EHLO);

     hello = US"EHLO";
     esmtp = TRUE;
 
     hello = US"EHLO";
     esmtp = TRUE;
 


@@ -2355,7 +2855,7 @@ while (done <= 0)
     /* Reject the HELO if its argument was invalid or non-existent. A
     successful check causes the argument to be saved in malloc store. */
 
     /* 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_argument))
+    if (!check_helo(smtp_cmd_data))

       {
       smtp_printf("501 Syntactically invalid %s argument(s)\r\n", hello);
 
       {
       smtp_printf("501 Syntactically invalid %s argument(s)\r\n", hello);
 


@@ -2385,7 +2885,7 @@ while (done <= 0)
     if (!sender_host_unknown)
       {
       BOOL old_helo_verified = helo_verified;
     if (!sender_host_unknown)
       {
       BOOL old_helo_verified = helo_verified;

-      uschar *p = smtp_cmd_argument;
+      uschar *p = smtp_cmd_data;

 
       while (*p != 0 && !isspace(*p)) { *p = tolower(*p); p++; }
       *p = 0;
 
       while (*p != 0 && !isspace(*p)) { *p = tolower(*p); p++; }
       *p = 0;


@@ -2440,7 +2940,8 @@ while (done <= 0)
     spf_init(sender_helo_name, sender_host_address);
 #endif
 
     spf_init(sender_helo_name, sender_host_address);
 #endif
 

-    /* Apply an ACL check if one is defined */
+    /* Apply an ACL check if one is defined; afterwards, recheck
+    synchronization in case the client started sending in a delay. */

 
     if (acl_smtp_helo != NULL)
       {
 
     if (acl_smtp_helo != NULL)
       {


@@ -2452,28 +2953,14 @@ while (done <= 0)
         host_build_sender_fullhost();  /* Rebuild */
         break;
         }
         host_build_sender_fullhost();  /* Rebuild */
         break;
         }

+      else if (!check_sync()) goto SYNC_FAILURE;

       }
 
       }
 

-    /* 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(). */
+    /* 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(). */

 
     auth_advertised = FALSE;
     pipelining_advertised = FALSE;
 
     auth_advertised = FALSE;
     pipelining_advertised = FALSE;


@@ -2481,21 +2968,46 @@ while (done <= 0)
     tls_advertised = FALSE;
     #endif
 
     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);
+    smtp_code = US"250 ";        /* Default response code plus space*/
+    if (user_msg == NULL)
+      {
+      s = string_sprintf("%.3s %s Hello %s%s%s",
+        smtp_code,
+        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);

 
 

-    ptr = Ustrlen(s);
-    size = ptr + 1;
+      ptr = Ustrlen(s);
+      size = ptr + 1;

 
 

-    if (sender_host_address != NULL)
+      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);
+        }
+      }
+
+    /* 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. */
+
+    else

       {
       {

-      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);
+      char *ss;
+      int codelen = 4;
+      smtp_message_code(&smtp_code, &codelen, &user_msg, NULL);
+      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;
+        }
+      ptr = Ustrlen(s);
+      size = ptr + 1;

       }
 
     s = string_cat(s, &size, &ptr, US"\r\n", 2);
       }
 
     s = string_cat(s, &size, &ptr, US"\r\n", 2);


@@ -2515,12 +3027,14 @@ while (done <= 0)
 
       if (thismessage_size_limit > 0)
         {
 
       if (thismessage_size_limit > 0)
         {

-        sprintf(CS big_buffer, "250-SIZE %d\r\n", thismessage_size_limit);
+        sprintf(CS big_buffer, "%.3s-SIZE %d\r\n", smtp_code,
+          thismessage_size_limit);

         s = string_cat(s, &size, &ptr, big_buffer, Ustrlen(big_buffer));
         }
       else
         {
         s = string_cat(s, &size, &ptr, big_buffer, Ustrlen(big_buffer));
         }
       else
         {

-        s = string_cat(s, &size, &ptr, US"250-SIZE\r\n", 10);
+        s = string_cat(s, &size, &ptr, smtp_code, 3);
+        s = string_cat(s, &size, &ptr, US"-SIZE\r\n", 7);

         }
 
       /* Exim does not do protocol conversion or data conversion. It is 8-bit
         }
 
       /* Exim does not do protocol conversion or data conversion. It is 8-bit


@@ -2531,14 +3045,18 @@ while (done <= 0)
       provided as an option. */
 
       if (accept_8bitmime)
       provided as an option. */
 
       if (accept_8bitmime)

-        s = string_cat(s, &size, &ptr, US"250-8BITMIME\r\n", 14);
+        {
+        s = string_cat(s, &size, &ptr, smtp_code, 3);
+        s = string_cat(s, &size, &ptr, US"-8BITMIME\r\n", 11);
+        }

 
       /* 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. */
 
       if (acl_smtp_etrn != NULL)
         {
 
       /* 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. */
 
       if (acl_smtp_etrn != NULL)
         {

-        s = string_cat(s, &size, &ptr, US"250-ETRN\r\n", 10);
+        s = string_cat(s, &size, &ptr, smtp_code, 3);
+        s = string_cat(s, &size, &ptr, US"-ETRN\r\n", 7);

         }
 
       /* Advertise EXPN if there's an ACL checking whether a host is
         }
 
       /* Advertise EXPN if there's an ACL checking whether a host is


@@ -2546,15 +3064,18 @@ while (done <= 0)
 
       if (acl_smtp_expn != NULL)
         {
 
       if (acl_smtp_expn != NULL)
         {

-        s = string_cat(s, &size, &ptr, US"250-EXPN\r\n", 10);
+        s = string_cat(s, &size, &ptr, smtp_code, 3);
+        s = string_cat(s, &size, &ptr, 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. */
 
         }
 
       /* 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)
+      if (pipelining_enable &&
+          verify_check_host(&pipelining_advertise_hosts) == OK)

         {
         {

-        s = string_cat(s, &size, &ptr, US"250-PIPELINING\r\n", 16);
+        s = string_cat(s, &size, &ptr, smtp_code, 3);
+        s = string_cat(s, &size, &ptr, US"-PIPELINING\r\n", 13);

         sync_cmd_limit = NON_SYNC_CMD_PIPELINING;
         pipelining_advertised = TRUE;
         }
         sync_cmd_limit = NON_SYNC_CMD_PIPELINING;
         pipelining_advertised = TRUE;
         }


@@ -2584,7 +3105,8 @@ while (done <= 0)
               int saveptr;
               if (first)
                 {
               int saveptr;
               if (first)
                 {

-                s = string_cat(s, &size, &ptr, US"250-AUTH", 8);
+                s = string_cat(s, &size, &ptr, smtp_code, 3);
+                s = string_cat(s, &size, &ptr, US"-AUTH", 5);

                 first = FALSE;
                 auth_advertised = TRUE;
                 }
                 first = FALSE;
                 auth_advertised = TRUE;
                 }


@@ -2610,14 +3132,16 @@ while (done <= 0)
       if (tls_active < 0 &&
           verify_check_host(&tls_advertise_hosts) != FAIL)
         {
       if (tls_active < 0 &&
           verify_check_host(&tls_advertise_hosts) != FAIL)
         {

-        s = string_cat(s, &size, &ptr, US"250-STARTTLS\r\n", 14);
+        s = string_cat(s, &size, &ptr, smtp_code, 3);
+        s = string_cat(s, &size, &ptr, US"-STARTTLS\r\n", 11);

         tls_advertised = TRUE;
         }
       #endif
 
       /* Finish off the multiline reply with one that is always available. */
 
         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);
+      s = string_cat(s, &size, &ptr, smtp_code, 3);
+      s = string_cat(s, &size, &ptr, US" HELP\r\n", 7);

       }
 
     /* Terminate the string (for debug), write it, and note that HELO/EHLO
       }
 
     /* Terminate the string (for debug), write it, and note that HELO/EHLO


@@ -2630,8 +3154,28 @@ while (done <= 0)
     #endif
 
     (void)fwrite(s, 1, ptr, smtp_out);
     #endif
 
     (void)fwrite(s, 1, ptr, smtp_out);

-    DEBUG(D_receive) debug_printf("SMTP>> %s", s);
+    DEBUG(D_receive)
+      {
+      uschar *cr;
+      while ((cr = Ustrchr(s, '\r')) != NULL)   /* lose CRs */
+        memmove(cr, cr + 1, (ptr--) - (cr - s));
+      debug_printf("SMTP>> %s", s);
+      }

     helo_seen = TRUE;
     helo_seen = TRUE;

+
+    /* 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;

     break;   /* HELO/EHLO */
 
 
     break;   /* HELO/EHLO */
 
 


@@ -2642,6 +3186,7 @@ while (done <= 0)
     it is the canonical extracted address which is all that is kept. */
 
     case MAIL_CMD:
     it is the canonical extracted address which is all that is kept. */
 
     case MAIL_CMD:

+    HAD(SCH_MAIL);

     smtp_mailcmd_count++;              /* Count for limit and ratelimit */
     was_rej_mail = TRUE;               /* Reset if accepted */
 
     smtp_mailcmd_count++;              /* Count for limit and ratelimit */
     was_rej_mail = TRUE;               /* Reset if accepted */
 


@@ -2660,7 +3205,7 @@ while (done <= 0)
       break;
       }
 
       break;
       }
 

-    if (smtp_cmd_argument[0] == 0)
+    if (smtp_cmd_data[0] == 0)

       {
       done = synprot_error(L_smtp_protocol_error, 501, NULL,
         US"MAIL must have an address operand");
       {
       done = synprot_error(L_smtp_protocol_error, 501, NULL,
         US"MAIL must have an address operand");


@@ -2699,7 +3244,7 @@ while (done <= 0)
       in order to be able to log the sender address on failure. */
 
       if (strcmpic(name, US"SIZE") == 0 &&
       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))
+          ((size = Ustrtoul(value, &end, 10)), *end == 0))

         {
         if ((size == ULONG_MAX && errno == ERANGE) || size > INT_MAX)
           size = INT_MAX;
         {
         if ((size == ULONG_MAX && errno == ERANGE) || size > INT_MAX)
           size = INT_MAX;


@@ -2819,8 +3364,8 @@ while (done <= 0)
     TRUE flag allows "<>" as a sender address. */
 
     raw_sender = ((rewrite_existflags & rewrite_smtp) != 0)?
     TRUE flag allows "<>" as a sender address. */
 
     raw_sender = ((rewrite_existflags & rewrite_smtp) != 0)?

-      rewrite_one(smtp_cmd_argument, rewrite_smtp, NULL, FALSE, US"",
-        global_rewrite_rules) : smtp_cmd_argument;
+      rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"",
+        global_rewrite_rules) : smtp_cmd_data;

 
     /* rfc821_domains = TRUE; << no longer needed */
     raw_sender =
 
     /* rfc821_domains = TRUE; << no longer needed */
     raw_sender =


@@ -2830,7 +3375,7 @@ while (done <= 0)
 
     if (raw_sender == NULL)
       {
 
     if (raw_sender == NULL)
       {

-      done = synprot_error(L_smtp_syntax_error, 501, smtp_cmd_argument, errmess);
+      done = synprot_error(L_smtp_syntax_error, 501, smtp_cmd_data, errmess);

       break;
       }
 
       break;
       }
 


@@ -2890,7 +3435,7 @@ while (done <= 0)
       else
         {
         smtp_printf("501 %s: sender address must contain a domain\r\n",
       else
         {
         smtp_printf("501 %s: sender address must contain a domain\r\n",

-          smtp_cmd_argument);
+          smtp_cmd_data);

         log_write(L_smtp_syntax_error,
           LOG_MAIN|LOG_REJECT,
           "unqualified sender rejected: <%s> %s%s",
         log_write(L_smtp_syntax_error,
           LOG_MAIN|LOG_REJECT,
           "unqualified sender rejected: <%s> %s%s",


@@ -2902,19 +3447,25 @@ while (done <= 0)
         }
       }
 
         }
       }
 

-    /* Apply an ACL check if one is defined, before responding */
+    /* 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. */

 
 

-    rc = (acl_smtp_mail == NULL)? OK :
-      acl_check(ACL_WHERE_MAIL, NULL, acl_smtp_mail, &user_msg, &log_msg);
+    if (acl_smtp_mail == NULL) rc = OK; else
+      {
+      rc = acl_check(ACL_WHERE_MAIL, NULL, acl_smtp_mail, &user_msg, &log_msg);
+      if (rc == OK && !pipelining_advertised && !check_sync())
+        goto SYNC_FAILURE;
+      }

 
     if (rc == OK || rc == DISCARD)
       {
 
     if (rc == OK || rc == DISCARD)
       {

-      smtp_printf("250 OK\r\n");
+      if (user_msg == NULL) smtp_printf("250 OK\r\n");
+        else smtp_user_msg(US"250", user_msg);

       smtp_delay_rcpt = smtp_rlr_base;
       recipients_discarded = (rc == DISCARD);
       was_rej_mail = FALSE;
       }
       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);
     else
       {
       done = smtp_handle_acl_fail(ACL_WHERE_MAIL, rc, user_msg, log_msg);


@@ -2923,16 +3474,15 @@ while (done <= 0)
     break;
 
 
     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. */
+    /* 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. */

 
     case RCPT_CMD:
 
     case RCPT_CMD:

+    HAD(SCH_RCPT);

     rcpt_count++;
     rcpt_count++;

-    was_rcpt = TRUE;
+    was_rcpt = rcpt_in_progress = 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
 
     /* There must be a sender address; if the sender was rejected and
     pipelining was advertised, we assume the client was pipelining, and do not


@@ -2958,7 +3508,7 @@ while (done <= 0)
 
     /* Check for an operand */
 
 
     /* Check for an operand */
 

-    if (smtp_cmd_argument[0] == 0)
+    if (smtp_cmd_data[0] == 0)

       {
       done = synprot_error(L_smtp_syntax_error, 501, NULL,
         US"RCPT must have an address operand");
       {
       done = synprot_error(L_smtp_syntax_error, 501, NULL,
         US"RCPT must have an address operand");


@@ -2970,8 +3520,8 @@ while (done <= 0)
     as a recipient address */
 
     recipient = ((rewrite_existflags & rewrite_smtp) != 0)?
     as a recipient address */
 
     recipient = ((rewrite_existflags & rewrite_smtp) != 0)?

-      rewrite_one(smtp_cmd_argument, rewrite_smtp, NULL, FALSE, US"",
-        global_rewrite_rules) : smtp_cmd_argument;
+      rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"",
+        global_rewrite_rules) : smtp_cmd_data;

 
     /* rfc821_domains = TRUE; << no longer needed */
     recipient = parse_extract_address(recipient, &errmess, &start, &end,
 
     /* rfc821_domains = TRUE; << no longer needed */
     recipient = parse_extract_address(recipient, &errmess, &start, &end,


@@ -2980,7 +3530,7 @@ while (done <= 0)
 
     if (recipient == NULL)
       {
 
     if (recipient == NULL)
       {

-      done = synprot_error(L_smtp_syntax_error, 501, smtp_cmd_argument, errmess);
+      done = synprot_error(L_smtp_syntax_error, 501, smtp_cmd_data, errmess);

       rcpt_fail_count++;
       break;
       }
       rcpt_fail_count++;
       break;
       }


@@ -3010,7 +3560,7 @@ while (done <= 0)
         {
         rcpt_fail_count++;
         smtp_printf("501 %s: recipient address must contain a domain\r\n",
         {
         rcpt_fail_count++;
         smtp_printf("501 %s: recipient address must contain a domain\r\n",

-          smtp_cmd_argument);
+          smtp_cmd_data);

         log_write(L_smtp_syntax_error,
           LOG_MAIN|LOG_REJECT, "unqualified recipient rejected: "
           "<%s> %s%s", recipient, host_and_ident(TRUE),
         log_write(L_smtp_syntax_error,
           LOG_MAIN|LOG_REJECT, "unqualified recipient rejected: "
           "<%s> %s%s", recipient, host_and_ident(TRUE),


@@ -3060,16 +3610,24 @@ while (done <= 0)
       }
 
     /* If the MAIL ACL discarded all the recipients, we bypass ACL checking
       }
 
     /* If the MAIL ACL discarded all the recipients, we bypass ACL checking

-    for them. Otherwise, check the access control list for this recipient. */
+    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. */

 
 

-    rc = recipients_discarded? DISCARD :
-      acl_check(ACL_WHERE_RCPT, recipient, acl_smtp_rcpt, &user_msg, &log_msg);
+    if (recipients_discarded) rc = DISCARD; else
+      {
+      rc = acl_check(ACL_WHERE_RCPT, recipient, acl_smtp_rcpt, &user_msg,
+        &log_msg);
+      if (rc == OK && !pipelining_advertised && !check_sync())
+        goto SYNC_FAILURE;
+      }

 
     /* The ACL was happy */
 
     if (rc == OK)
       {
 
     /* The ACL was happy */
 
     if (rc == OK)
       {

-      smtp_printf("250 Accepted\r\n");
+      if (user_msg == NULL) smtp_printf("250 Accepted\r\n");
+        else smtp_user_msg(US"250", user_msg);

       receive_add_recipient(recipient, -1);
       }
 
       receive_add_recipient(recipient, -1);
       }
 


@@ -3077,7 +3635,8 @@ while (done <= 0)
 
     else if (rc == DISCARD)
       {
 
     else if (rc == DISCARD)
       {

-      smtp_printf("250 Accepted\r\n");
+      if (user_msg == NULL) smtp_printf("250 Accepted\r\n");
+        else smtp_user_msg(US"250", user_msg);

       rcpt_fail_count++;
       discarded = TRUE;
       log_write(0, LOG_MAIN|LOG_REJECT, "%s F=<%s> rejected RCPT %s: "
       rcpt_fail_count++;
       discarded = TRUE;
       log_write(0, LOG_MAIN|LOG_REJECT, "%s F=<%s> rejected RCPT %s: "


@@ -3113,13 +3672,29 @@ while (done <= 0)
         DATA command.
 
     The example in the pipelining RFC 2920 uses 554, but I use 503 here
         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. */
+    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). */

 
     case DATA_CMD:
 
     case DATA_CMD:

+    HAD(SCH_DATA);

     if (!discarded && recipients_count <= 0)
       {
     if (!discarded && recipients_count <= 0)
       {

+      if (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 (pipelining_advertised && last_was_rcpt)
       if (pipelining_advertised && last_was_rcpt)

-        smtp_printf("503 valid RCPT command must precede DATA\r\n");
+        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");
       else
         done = synprot_error(L_smtp_protocol_error, 503, NULL,
           US"valid RCPT command must precede DATA");


@@ -3134,17 +3709,23 @@ while (done <= 0)
       break;
       }
 
       break;
       }
 

+    /* If there is an ACL, re-check the synchronization afterwards, since the
+    ACL may have delayed. */
+

     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 (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 && !check_sync()) goto SYNC_FAILURE;

       }
 
     if (rc == OK)
       {
       }
 
     if (rc == OK)
       {

-      smtp_printf("354 Enter message, ending with \".\" on a line by itself\r\n");
+      if (user_msg == NULL)
+        smtp_printf("354 Enter message, ending with \".\" on a line by itself\r\n");
+      else smtp_user_msg(US"354", user_msg);

       done = 3;
       message_ended = END_NOTENDED;   /* Indicate in middle of data */
       }
       done = 3;
       message_ended = END_NOTENDED;   /* Indicate in middle of data */
       }


@@ -3153,11 +3734,11 @@ while (done <= 0)
 
     else
       done = smtp_handle_acl_fail(ACL_WHERE_PREDATA, rc, user_msg, log_msg);
 
     else
       done = smtp_handle_acl_fail(ACL_WHERE_PREDATA, rc, user_msg, log_msg);

-

     break;
 
 
     case VRFY_CMD:
     break;
 
 
     case VRFY_CMD:

+    HAD(SCH_VRFY);

     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);
     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);


@@ -3167,7 +3748,7 @@ while (done <= 0)
       uschar *s = NULL;
 
       /* rfc821_domains = TRUE; << no longer needed */
       uschar *s = NULL;
 
       /* rfc821_domains = TRUE; << no longer needed */

-      address = parse_extract_address(smtp_cmd_argument, &errmess, &start, &end,
+      address = parse_extract_address(smtp_cmd_data, &errmess, &start, &end,

         &recipient_domain, FALSE);
       /* rfc821_domains = FALSE; << no longer needed */
 
         &recipient_domain, FALSE);
       /* rfc821_domains = FALSE; << no longer needed */
 


@@ -3184,14 +3765,14 @@ while (done <= 0)
           break;
 
           case DEFER:
           break;
 
           case DEFER:

-          s = (addr->message != NULL)?
-            string_sprintf("451 <%s> %s", address, addr->message) :
+          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:
             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) :
+          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));
             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));


@@ -3205,6 +3786,7 @@ while (done <= 0)
 
 
     case EXPN_CMD:
 
 
     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_EXPN, rc, user_msg, log_msg);
     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);


@@ -3212,7 +3794,7 @@ while (done <= 0)
       {
       BOOL save_log_testing_mode = log_testing_mode;
       address_test_mode = log_testing_mode = TRUE;
       {
       BOOL save_log_testing_mode = log_testing_mode;
       address_test_mode = log_testing_mode = TRUE;

-      (void) verify_address(deliver_make_addr(smtp_cmd_argument, FALSE),
+      (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);
       address_test_mode = FALSE;
         smtp_out, vopt_is_recipient | vopt_qualify | vopt_expn, -1, -1, -1,
         NULL, NULL, NULL);
       address_test_mode = FALSE;


@@ -3224,6 +3806,7 @@ while (done <= 0)
     #ifdef SUPPORT_TLS
 
     case STARTTLS_CMD:
     #ifdef SUPPORT_TLS
 
     case STARTTLS_CMD:

+    HAD(SCH_STARTTLS);

     if (!tls_advertised)
       {
       done = synprot_error(L_smtp_protocol_error, 503, NULL,
     if (!tls_advertised)
       {
       done = synprot_error(L_smtp_protocol_error, 503, NULL,


@@ -3262,7 +3845,8 @@ while (done <= 0)
     We must allow for an extra EHLO command and an extra AUTH command after
     STARTTLS that don't add to the nonmail command count. */
 
     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 ((rc = tls_server_start(tls_require_ciphers, gnutls_require_mac,
+           gnutls_require_kx, gnutls_require_proto)) == OK)

       {
       if (!tls_remember_esmtp)
         helo_seen = esmtp = auth_advertised = pipelining_advertised = FALSE;
       {
       if (!tls_remember_esmtp)
         helo_seen = esmtp = auth_advertised = pipelining_advertised = FALSE;


@@ -3312,11 +3896,29 @@ while (done <= 0)
         case EOF_CMD:
         log_write(L_smtp_connection, LOG_MAIN, "%s closed by EOF",
           smtp_get_connection_info());
         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;
 
         done = 2;
         break;
 

+        /* It is perhaps arguable as to which exit ACL should be called here,
+        but as it is probably a situtation 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:
         case QUIT_CMD:

-        smtp_printf("221 %s closing connection\r\n", smtp_active_hostname);
+        user_msg = NULL;
+        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);
+          }
+        if (user_msg == NULL)
+          smtp_printf("221 %s closing connection\r\n", smtp_active_hostname);
+        else
+          smtp_respond(US"221", 3, TRUE, user_msg);

         log_write(L_smtp_connection, LOG_MAIN, "%s closed by QUIT",
           smtp_get_connection_info());
         done = 2;
         log_write(L_smtp_connection, LOG_MAIN, "%s closed by QUIT",
           smtp_get_connection_info());
         done = 2;


@@ -3337,21 +3939,19 @@ while (done <= 0)
     message. */
 
     case QUIT_CMD:
     message. */
 
     case QUIT_CMD:

+    HAD(SCH_QUIT);

     incomplete_transaction_log(US"QUIT");
     incomplete_transaction_log(US"QUIT");

-

     if (acl_smtp_quit != NULL)
       {
     if (acl_smtp_quit != NULL)
       {

-      rc = acl_check(ACL_WHERE_QUIT, NULL, acl_smtp_quit,&user_msg,&log_msg);
+      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);
       }
       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
     if (user_msg == NULL)
       smtp_printf("221 %s closing connection\r\n", smtp_active_hostname);
     else

-      smtp_printf("221 %s\r\n", user_msg);
+      smtp_respond(US"221", 3, TRUE, user_msg);

 
     #ifdef SUPPORT_TLS
     tls_close(TRUE);
 
     #ifdef SUPPORT_TLS
     tls_close(TRUE);


@@ -3364,6 +3964,7 @@ while (done <= 0)
 
 
     case RSET_CMD:
 
 
     case RSET_CMD:

+    HAD(SCH_RSET);

     incomplete_transaction_log(US"RSET");
     smtp_reset(reset_point);
     toomany = FALSE;
     incomplete_transaction_log(US"RSET");
     smtp_reset(reset_point);
     toomany = FALSE;


@@ -3373,22 +3974,27 @@ while (done <= 0)
 
 
     case NOOP_CMD:
 
 
     case NOOP_CMD:

+    HAD(SCH_NOOP);

     smtp_printf("250 OK\r\n");
     break;
 
 
     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. */
+    /* 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. */

 
     case HELP_CMD:
 
     case HELP_CMD:

+    HAD(SCH_HELP);

     smtp_printf("214-Commands supported:\r\n");
       {
       uschar buffer[256];
       buffer[0] = 0;
       Ustrcat(buffer, " AUTH");
       #ifdef SUPPORT_TLS
     smtp_printf("214-Commands supported:\r\n");
       {
       uschar buffer[256];
       buffer[0] = 0;
       Ustrcat(buffer, " AUTH");
       #ifdef SUPPORT_TLS

-      Ustrcat(buffer, " STARTTLS");
+      if (tls_active < 0 &&
+          verify_check_host(&tls_advertise_hosts) != FAIL)
+        Ustrcat(buffer, " STARTTLS");

       #endif
       Ustrcat(buffer, " HELO EHLO MAIL RCPT DATA");
       Ustrcat(buffer, " NOOP QUIT RSET HELP");
       #endif
       Ustrcat(buffer, " HELO EHLO MAIL RCPT DATA");
       Ustrcat(buffer, " NOOP QUIT RSET HELP");


@@ -3402,7 +4008,8 @@ while (done <= 0)
 
     case EOF_CMD:
     incomplete_transaction_log(US"connection lost");
 
     case EOF_CMD:
     incomplete_transaction_log(US"connection lost");

-    smtp_printf("421 %s lost input connection\r\n", smtp_active_hostname);
+    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.
 
     /* 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.


@@ -3423,6 +4030,7 @@ while (done <= 0)
 
 
     case ETRN_CMD:
 
 
     case ETRN_CMD:

+    HAD(SCH_ETRN);

     if (sender_address != NULL)
       {
       done = synprot_error(L_smtp_protocol_error, 503, NULL,
     if (sender_address != NULL)
       {
       done = synprot_error(L_smtp_protocol_error, 503, NULL,


@@ -3442,7 +4050,7 @@ while (done <= 0)
 
     /* Compute the serialization key for this command. */
 
 
     /* Compute the serialization key for this command. */
 

-    etrn_serialize_key = string_sprintf("etrn-%s\n", smtp_cmd_argument);
+    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,
 
     /* 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,


@@ -3454,7 +4062,7 @@ while (done <= 0)
       uschar *error;
       BOOL rc;
       etrn_command = smtp_etrn_command;
       uschar *error;
       BOOL rc;
       etrn_command = smtp_etrn_command;

-      deliver_domain = smtp_cmd_argument;
+      deliver_domain = smtp_cmd_data;

       rc = transport_set_up_command(&argv, smtp_etrn_command, TRUE, 0, NULL,
         US"ETRN processing", &error);
       deliver_domain = NULL;
       rc = transport_set_up_command(&argv, smtp_etrn_command, TRUE, 0, NULL,
         US"ETRN processing", &error);
       deliver_domain = NULL;


@@ -3471,7 +4079,7 @@ while (done <= 0)
 
     else
       {
 
     else
       {

-      if (*smtp_cmd_argument++ != '#')
+      if (*smtp_cmd_data++ != '#')

         {
         done = synprot_error(L_smtp_syntax_error, 501, NULL,
           US"argument must begin with #");
         {
         done = synprot_error(L_smtp_syntax_error, 501, NULL,
           US"argument must begin with #");


@@ -3479,7 +4087,7 @@ while (done <= 0)
         }
       etrn_command = US"exim -R";
       argv = child_exec_exim(CEE_RETURN_ARGV, TRUE, NULL, TRUE, 2, US"-R",
         }
       etrn_command = US"exim -R";
       argv = child_exec_exim(CEE_RETURN_ARGV, TRUE, NULL, TRUE, 2, US"-R",

-        smtp_cmd_argument);
+        smtp_cmd_data);

       }
 
     /* If we are host-testing, don't actually do anything. */
       }
 
     /* If we are host-testing, don't actually do anything. */


@@ -3491,7 +4099,8 @@ while (done <= 0)
         debug_printf("ETRN command is: %s\n", etrn_command);
         debug_printf("ETRN command execution skipped\n");
         }
         debug_printf("ETRN command is: %s\n", etrn_command);
         debug_printf("ETRN command execution skipped\n");
         }

-      smtp_printf("250 OK\r\n");
+      if (user_msg == NULL) smtp_printf("250 OK\r\n");
+        else smtp_user_msg(US"250", user_msg);

       break;
       }
 
       break;
       }
 


@@ -3501,7 +4110,7 @@ while (done <= 0)
 
     if (smtp_etrn_serialize && !enq_start(etrn_serialize_key))
       {
 
     if (smtp_etrn_serialize && !enq_start(etrn_serialize_key))
       {

-      smtp_printf("458 Already processing %s\r\n", smtp_cmd_argument);
+      smtp_printf("458 Already processing %s\r\n", smtp_cmd_data);

       break;
       }
 
       break;
       }
 


@@ -3567,7 +4176,11 @@ while (done <= 0)
       smtp_printf("458 Unable to fork process\r\n");
       if (smtp_etrn_serialize) enq_end(etrn_serialize_key);
       }
       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");
+    else
+      {
+      if (user_msg == NULL) smtp_printf("250 OK\r\n");
+        else smtp_user_msg(US"250", user_msg);
+      }

 
     signal(SIGCHLD, oldsignal);
     break;
 
     signal(SIGCHLD, oldsignal);
     break;


@@ -3589,6 +4202,7 @@ while (done <= 0)
 
 
     case BADSYN_CMD:
 
 
     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 (smtp_inend >= smtp_inbuffer + in_buffer_size)
       smtp_inend = smtp_inbuffer + in_buffer_size - 1;
     c = smtp_inend - smtp_inptr;


@@ -3601,17 +4215,20 @@ while (done <= 0)
       pipelining_advertised? "" : " not",
       smtp_cmd_buffer, host_and_ident(TRUE),
       string_printing(smtp_inptr));
       pipelining_advertised? "" : " not",
       smtp_cmd_buffer, host_and_ident(TRUE),
       string_printing(smtp_inptr));

-    smtp_printf("554 SMTP synchronization error\r\n");
+    smtp_notquit_exit(US"synchronization-error", US"554",
+      US"SMTP synchronization error");

     done = 1;   /* Pretend eof - drops connection */
     break;
 
 
     case TOO_MANY_NONMAIL_CMD:
     done = 1;   /* Pretend eof - drops connection */
     break;
 
 
     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),
     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_cmd_argument - smtp_cmd_buffer, smtp_cmd_buffer);
-    smtp_printf("554 Too many nonmail commands\r\n");
+      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;
 
     done = 1;   /* Pretend eof - drops connection */
     break;
 


@@ -3624,7 +4241,8 @@ while (done <= 0)
         string_printing(smtp_cmd_buffer), host_and_ident(TRUE),
         US"unrecognized command");
       incomplete_transaction_log(US"unrecognized command");
         string_printing(smtp_cmd_buffer), host_and_ident(TRUE),
         US"unrecognized command");
       incomplete_transaction_log(US"unrecognized command");

-      smtp_printf("500 Too many unrecognized commands\r\n");
+      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),
       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),