X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/3bf3a99e444713b1b4070b8d12811741ed69258b..36771878fa93a04ecf5bdd71ad3c3c380a16aa03:/src/src/smtp_in.c

diff --git a/src/src/smtp_in.c b/src/src/smtp_in.c
index 29f656834..eb032bb52 100644
--- a/src/src/smtp_in.c
+++ b/src/src/smtp_in.c
@@ -347,7 +347,7 @@ wouldblock_reading(void)
 {
 int fd, rc;
 fd_set fds;
-struct timeval tzero;
+struct timeval tzero = {.tv_sec = 0, .tv_usec = 0};
 
 #ifndef DISABLE_TLS
 if (tls_in.active.sock >= 0)
@@ -360,8 +360,6 @@ if (smtp_inptr < smtp_inend)
 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 */
@@ -587,6 +585,8 @@ smtp_get_cache(void)
 {
 #ifndef DISABLE_DKIM
 int n = smtp_inend - smtp_inptr;
+if (chunking_state == CHUNKING_LAST && chunking_data_left < n)
+  n = chunking_data_left;
 if (n > 0)
   dkim_exim_verify_feed(smtp_inptr, n);
 #endif
@@ -624,9 +624,7 @@ for(;;)
   if (chunking_data_left > 0)
     return lwr_receive_getc(chunking_data_left--);
 
-  receive_getc = lwr_receive_getc;
-  receive_getbuf = lwr_receive_getbuf;
-  receive_ungetc = lwr_receive_ungetc;
+  bdat_pop_receive_functions();
 #ifndef DISABLE_DKIM
   dkim_save = dkim_collect_input;
   dkim_collect_input = 0;
@@ -730,9 +728,7 @@ next_cmd:
 	  goto repeat_until_rset;
 	  }
 
-      receive_getc = bdat_getc;
-      receive_getbuf = bdat_getbuf;	/* r~getbuf is never actually used */
-      receive_ungetc = bdat_ungetc;
+      bdat_push_receive_functions();
 #ifndef DISABLE_DKIM
       dkim_collect_input = dkim_save;
 #endif
@@ -765,9 +761,7 @@ while (chunking_data_left)
   if (!bdat_getbuf(&n)) break;
   }
 
-receive_getc = lwr_receive_getc;
-receive_getbuf = lwr_receive_getbuf;
-receive_ungetc = lwr_receive_ungetc;
+bdat_pop_receive_functions();
 
 if (chunking_state != CHUNKING_LAST)
   {
@@ -777,7 +771,35 @@ if (chunking_state != CHUNKING_LAST)
 }
 
 
+void
+bdat_push_receive_functions(void)
+{
+/* push the current receive_* function on the "stack", and
+replace them by bdat_getc(), which in turn will use the lwr_receive_*
+functions to do the dirty work. */
+if (lwr_receive_getc == NULL)
+  {
+  lwr_receive_getc = receive_getc;
+  lwr_receive_getbuf = receive_getbuf;
+  lwr_receive_ungetc = receive_ungetc;
+  }
+else
+  {
+  DEBUG(D_receive) debug_printf("chunking double-push receive functions\n");
+  }
+
+receive_getc = bdat_getc;
+receive_ungetc = bdat_ungetc;
+}
 
+void
+bdat_pop_receive_functions(void)
+{
+receive_getc = lwr_receive_getc;
+receive_getbuf = lwr_receive_getbuf;
+receive_ungetc = lwr_receive_ungetc;
+lwr_receive_getc = lwr_receive_getbuf = lwr_receive_ungetc = NULL;
+}
 
 /*************************************************
 *          SMTP version of ungetc()              *
@@ -1969,12 +1991,13 @@ extract_option(uschar **name, uschar **value)
 uschar *n;
 uschar *v = smtp_cmd_data + Ustrlen(smtp_cmd_data) - 1;
 while (isspace(*v)) v--;
-v[1] = 0;
+v[1] = '\0';
 while (v > smtp_cmd_data && *v != '=' && !isspace(*v))
   {
   /* Take care to not stop at a space embedded in a quoted local-part */
 
-  if (*v == '"') do v--; while (*v != '"' && v > smtp_cmd_data+1);
+  if ((*v == '"') && (v > smtp_cmd_data + 1))
+    do v--; while (*v != '"' && v > smtp_cmd_data+1);
   v--;
   }
 
@@ -2109,7 +2132,11 @@ while (acl_warn_logged)
   acl_warn_logged = acl_warn_logged->next;
   store_free(this);
   }
+
+message_tidyup();
 store_reset(reset_point);
+
+message_start();
 return store_mark();
 }
 
@@ -2186,7 +2213,7 @@ while (done <= 0)
 
     case MAIL_CMD:
       smtp_mailcmd_count++;              /* Count for no-mail log */
-      if (sender_address != NULL)
+      if (sender_address)
 	/* The function moan_smtp_batch() does not return. */
 	moan_smtp_batch(smtp_cmd_buffer, "503 Sender already given");
 
@@ -2523,6 +2550,7 @@ receive_ungetc = smtp_ungetc;
 receive_feof = smtp_feof;
 receive_ferror = smtp_ferror;
 receive_smtp_buffered = smtp_buffered;
+lwr_receive_getc = lwr_receive_getbuf = lwr_receive_ungetc = NULL;
 smtp_inptr = smtp_inend = smtp_inbuffer;
 smtp_had_eof = smtp_had_error = 0;
 
@@ -2893,7 +2921,7 @@ if (!f.sender_host_unknown)
 if (smtp_batched_input) return TRUE;
 
 /* If valid Proxy Protocol source is connecting, set up session.
- * Failure will not allow any SMTP function other than QUIT. */
+Failure will not allow any SMTP function other than QUIT. */
 
 #ifdef SUPPORT_PROXY
 proxy_session = FALSE;
@@ -2902,16 +2930,16 @@ if (check_proxy_protocol_host())
   setup_proxy_protocol_host();
 #endif
 
-  /* Start up TLS if tls_on_connect is set. This is for supporting the legacy
-  smtps port for use with older style SSL MTAs. */
+/* Start up TLS if tls_on_connect is set. This is for supporting the legacy
+smtps port for use with older style SSL MTAs. */
 
 #ifndef DISABLE_TLS
-  if (tls_in.on_connect)
-    {
-    if (tls_server_start(&user_msg) != OK)
-      return smtp_log_tls_fail(user_msg);
-    cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd = TRUE;
-    }
+if (tls_in.on_connect)
+  {
+  if (tls_server_start(&user_msg) != OK)
+    return smtp_log_tls_fail(user_msg);
+  cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd = TRUE;
+  }
 #endif
 
 /* Run the connect ACL if it exists */
@@ -3279,18 +3307,7 @@ int codelen = 3;
 uschar *smtp_code;
 uschar *lognl;
 uschar *sender_info = US"";
-uschar *what =
-#ifdef WITH_CONTENT_SCAN
-  where == ACL_WHERE_MIME ? US"during MIME ACL checks" :
-#endif
-  where == ACL_WHERE_PREDATA ? US"DATA" :
-  where == ACL_WHERE_DATA ? US"after DATA" :
-#ifndef DISABLE_PRDR
-  where == ACL_WHERE_PRDR ? US"after DATA PRDR" :
-#endif
-  smtp_cmd_data ?
-    string_sprintf("%s %s", acl_wherenames[where], smtp_cmd_data) :
-    string_sprintf("%s in \"connect\" ACL", acl_wherenames[where]);
+uschar *what;
 
 if (drop) rc = FAIL;
 
@@ -3306,19 +3323,45 @@ fixed, sender_address at this point became the rewritten address. I'm not sure
 this is what should be logged, so I've changed to logging the unrewritten
 address to retain backward compatibility. */
 
-#ifndef WITH_CONTENT_SCAN
-if (where == ACL_WHERE_RCPT || where == ACL_WHERE_DATA)
-#else
-if (where == ACL_WHERE_RCPT || where == ACL_WHERE_DATA || where == ACL_WHERE_MIME)
+switch (where)
+  {
+#ifdef WITH_CONTENT_SCAN
+  case ACL_WHERE_MIME:		what = US"during MIME ACL checks";	break;
+#endif
+  case ACL_WHERE_PREDATA:	what = US"DATA";			break;
+  case ACL_WHERE_DATA:		what = US"after DATA";			break;
+#ifndef DISABLE_PRDR
+  case ACL_WHERE_PRDR:		what = US"after DATA PRDR";		break;
 #endif
+  default:
+    {
+    uschar * place = smtp_cmd_data ? smtp_cmd_data : US"in \"connect\" ACL";
+    int lim = 100;
+
+    if (where == ACL_WHERE_AUTH)	/* avoid logging auth creds */
+      {
+      uschar * s;
+      for (s = smtp_cmd_data; *s && !isspace(*s); ) s++;
+      lim = s - smtp_cmd_data;	/* atop after method */
+      }
+    what = string_sprintf("%s %.*s", acl_wherenames[where], lim, place);
+    }
+  }
+switch (where)
   {
-  sender_info = string_sprintf("F=<%s>%s%s%s%s ",
-    sender_address_unrewritten ? sender_address_unrewritten : sender_address,
-    sender_host_authenticated ? US" A="                                    : US"",
-    sender_host_authenticated ? sender_host_authenticated                  : US"",
-    sender_host_authenticated && authenticated_id ? US":"                  : US"",
-    sender_host_authenticated && authenticated_id ? authenticated_id       : US""
-    );
+  case ACL_WHERE_RCPT:
+  case ACL_WHERE_DATA:
+#ifdef WITH_CONTENT_SCAN
+  case ACL_WHERE_MIME:
+#endif
+    sender_info = string_sprintf("F=<%s>%s%s%s%s ",
+      sender_address_unrewritten ? sender_address_unrewritten : sender_address,
+      sender_host_authenticated ? US" A="                                    : US"",
+      sender_host_authenticated ? sender_host_authenticated                  : US"",
+      sender_host_authenticated && authenticated_id ? US":"                  : US"",
+      sender_host_authenticated && authenticated_id ? authenticated_id       : US""
+      );
+  break;
   }
 
 /* If there's been a sender verification failure with a specific message, and
@@ -3819,8 +3862,8 @@ if (  acl_smtp_quit
     log_write(0, LOG_MAIN|LOG_PANIC, "ACL for QUIT returned ERROR: %s",
       *log_msgp);
 
-#ifdef TCP_CORK
-(void) setsockopt(fileno(smtp_out), IPPROTO_TCP, TCP_CORK, US &on, sizeof(on));
+#ifdef EXIM_TCP_CORK
+(void) setsockopt(fileno(smtp_out), IPPROTO_TCP, EXIM_TCP_CORK, US &on, sizeof(on));
 #endif
 
 if (*user_msgp)
@@ -3828,12 +3871,35 @@ if (*user_msgp)
 else
   smtp_printf("221 %s closing connection\r\n", FALSE, smtp_active_hostname);
 
-#ifndef DISABLE_TLS
+#ifdef SERVERSIDE_CLOSE_NOWAIT
+# ifndef DISABLE_TLS
 tls_close(NULL, TLS_SHUTDOWN_NOWAIT);
-#endif
+# endif
 
 log_write(L_smtp_connection, LOG_MAIN, "%s closed by QUIT",
   smtp_get_connection_info());
+#else
+
+# ifndef DISABLE_TLS
+tls_close(NULL, TLS_SHUTDOWN_WAIT);
+# endif
+
+log_write(L_smtp_connection, LOG_MAIN, "%s closed by QUIT",
+  smtp_get_connection_info());
+
+/* Pause, hoping client will FIN first so that they get the TIME_WAIT.
+The socket should become readble (though with no data) */
+
+  {
+  int fd = fileno(smtp_in);
+  fd_set fds;
+  struct timeval t_limit = {.tv_sec = 0, .tv_usec = 200*1000};
+
+  FD_ZERO(&fds);
+  FD_SET(fd, &fds);
+  (void) select(fd + 1, (SELECT_ARG2_TYPE *)&fds, NULL, NULL, &t_limit);
+  }
+#endif	/*!DAEMON_CLOSE_NOWAIT*/
 }
 
 
@@ -3847,6 +3913,13 @@ cmd_list[CMD_LIST_RSET].is_mail_cmd = FALSE;
 }
 
 
+static int
+expand_mailmax(const uschar * s)
+{
+if (!(s = expand_cstring(s)))
+  log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand smtp_accept_max_per_connection");
+return *s ? Uatoi(s) : 0;
+}
 
 /*************************************************
 *       Initialize for SMTP incoming message     *
@@ -3877,6 +3950,7 @@ int
 smtp_setup_msg(void)
 {
 int done = 0;
+int mailmax = -1;
 BOOL toomany = FALSE;
 BOOL discarded = FALSE;
 BOOL last_was_rej_mail = FALSE;
@@ -3903,6 +3977,14 @@ cmd_list[CMD_LIST_EHLO].is_mail_cmd = TRUE;
 cmd_list[CMD_LIST_STARTTLS].is_mail_cmd = TRUE;
 #endif
 
+if (lwr_receive_getc != NULL)
+  {
+  /* This should have already happened, but if we've gotten confused,
+  force a reset here. */
+  DEBUG(D_receive) debug_printf("WARNING: smtp_setup_msg had to restore receive functions to lowers\n");
+  bdat_pop_receive_functions();
+  }
+
 /* Set the local signal handler for SIGTERM - it tries to end off tidily */
 
 had_command_sigterm = 0;
@@ -3912,6 +3994,12 @@ os_non_restarting_signal(SIGTERM, command_sigterm_handler);
 
 if (smtp_batched_input) return smtp_setup_batch_msg();
 
+#ifdef TCP_QUICKACK
+if (smtp_in)		/* Avoid pure-ACKs while in cmd pingpong phase */
+  (void) setsockopt(fileno(smtp_in), IPPROTO_TCP, TCP_QUICKACK,
+	  US &off, sizeof(off));
+#endif
+
 /* Deal with SMTP commands. This loop is exited by setting done to a POSITIVE
 value. The values are 2 larger than the required yield of the function. */
 
@@ -3969,12 +4057,6 @@ while (done <= 0)
     }
 #endif
 
-#ifdef TCP_QUICKACK
-  if (smtp_in)		/* Avoid pure-ACKs while in cmd pingpong phase */
-    (void) setsockopt(fileno(smtp_in), IPPROTO_TCP, TCP_QUICKACK,
-	    US &off, sizeof(off));
-#endif
-
   switch(smtp_read_command(
 #ifndef DISABLE_PIPE_CONNECT
 	  !fl.pipe_connect_acceptable,
@@ -4035,21 +4117,18 @@ while (done <= 0)
       /* Find the name of the requested authentication mechanism. */
 
       s = smtp_cmd_data;
-      while ((c = *smtp_cmd_data) != 0 && !isspace(c))
-	{
+      for (; (c = *smtp_cmd_data) && !isspace(c); smtp_cmd_data++)
 	if (!isalnum(c) && c != '-' && c != '_')
 	  {
 	  done = synprot_error(L_smtp_syntax_error, 501, NULL,
 	    US"invalid character in authentication mechanism name");
 	  goto COMMAND_LOOP;
 	  }
-	smtp_cmd_data++;
-	}
 
       /* If not at the end of the line, we must be at white space. Terminate the
       name and move the pointer on to any data that may be present. */
 
-      if (*smtp_cmd_data != 0)
+      if (*smtp_cmd_data)
 	{
 	*smtp_cmd_data++ = 0;
 	while (isspace(*smtp_cmd_data)) smtp_cmd_data++;
@@ -4237,6 +4316,9 @@ while (done <= 0)
       fl.smtputf8_advertised = FALSE;
 #endif
 
+      /* Expand the per-connection message count limit option */
+      mailmax = expand_mailmax(smtp_accept_max_per_connection);
+
       smtp_code = US"250 ";        /* Default response code plus space*/
       if (!user_msg)
 	{
@@ -4296,6 +4378,19 @@ while (done <= 0)
 	  g = string_catn(g, US"-SIZE\r\n", 7);
 	  }
 
+#ifdef EXPERIMENTAL_ESMTP_LIMITS
+	if (  (mailmax > 0 || recipients_max)
+	   && verify_check_host(&limits_advertise_hosts) == OK)
+	  {
+	  g = string_fmt_append(g, "%.3s-LIMITS", smtp_code);
+	  if (mailmax > 0)
+	    g = string_fmt_append(g, " MAILMAX=%d", mailmax);
+	  if (recipients_max)
+	    g = string_fmt_append(g, " RCPTMAX=%d", recipients_max);
+	  g = string_catn(g, US"\r\n", 2);
+	  }
+#endif
+
 	/* Exim does not do protocol conversion or data conversion. It is 8-bit
 	clean; if it has an 8-bit character in its hand, it just sends it. It
 	cannot therefore specify 8BITMIME and remain consistent with the RFCs.
@@ -4508,16 +4603,20 @@ while (done <= 0)
     case MAIL_CMD:
       HAD(SCH_MAIL);
       smtp_mailcmd_count++;              /* Count for limit and ratelimit */
+      message_start();
       was_rej_mail = TRUE;               /* Reset if accepted */
       env_mail_type_t * mail_args;       /* Sanity check & validate args */
 
-      if (fl.helo_required && !fl.helo_seen)
-	{
-	smtp_printf("503 HELO or EHLO required\r\n", FALSE);
-	log_write(0, LOG_MAIN|LOG_REJECT, "rejected MAIL from %s: no "
-	  "HELO/EHLO given", host_and_ident(FALSE));
-	break;
-	}
+      if (!fl.helo_seen)
+	if (fl.helo_required)
+	  {
+	  smtp_printf("503 HELO or EHLO required\r\n", FALSE);
+	  log_write(0, LOG_MAIN|LOG_REJECT, "rejected MAIL from %s: no "
+	    "HELO/EHLO given", host_and_ident(FALSE));
+	  break;
+	  }
+	else if (mailmax < 0)
+	  mailmax = expand_mailmax(smtp_accept_max_per_connection);
 
       if (sender_address)
 	{
@@ -4536,8 +4635,7 @@ while (done <= 0)
       /* Check to see if the limit for messages per connection would be
       exceeded by accepting further messages. */
 
-      if (smtp_accept_max_per_connection > 0 &&
-	  smtp_mailcmd_count > smtp_accept_max_per_connection)
+      if (mailmax > 0 && smtp_mailcmd_count > mailmax)
 	{
 	smtp_printf("421 too many messages in this connection\r\n", FALSE);
 	log_write(0, LOG_MAIN|LOG_REJECT, "rejected MAIL command %s: too many "
@@ -5221,16 +5319,7 @@ while (done <= 0)
       DEBUG(D_receive) debug_printf("chunking state %d, %d bytes\n",
 				    (int)chunking_state, chunking_data_left);
 
-      /* push the current receive_* function on the "stack", and
-      replace them by bdat_getc(), which in turn will use the lwr_receive_*
-      functions to do the dirty work. */
-      lwr_receive_getc = receive_getc;
-      lwr_receive_getbuf = receive_getbuf;
-      lwr_receive_ungetc = receive_ungetc;
-
-      receive_getc = bdat_getc;
-      receive_ungetc = bdat_ungetc;
-
+      f.bdat_readers_wanted = TRUE;
       f.dot_ends = FALSE;
 
       goto DATA_BDAT;
@@ -5239,6 +5328,7 @@ while (done <= 0)
     case DATA_CMD:
       HAD(SCH_DATA);
       f.dot_ends = TRUE;
+      f.bdat_readers_wanted = FALSE
 
     DATA_BDAT:		/* Common code for DATA and BDAT */
 #ifndef DISABLE_PIPE_CONNECT
@@ -5267,7 +5357,10 @@ while (done <= 0)
 	    : US"valid RCPT command must precede BDAT");
 
 	if (chunking_state > CHUNKING_OFFERED)
+	  {
+	  bdat_push_receive_functions();
 	  bdat_flush_data();
+	  }
 	break;
 	}
 
@@ -5306,6 +5399,9 @@ while (done <= 0)
 	    }
 	  }
 
+	if (f.bdat_readers_wanted)
+	  bdat_push_receive_functions();
+
 	if (user_msg)
 	  smtp_user_msg(US"354", user_msg);
 	else