SMTP-Relaying: implement a method to choose a relay by sender email address or username
[citadel.git] / citadel / modules / smtp / smtp_util.c
index fa59255eb04c29f8681ab5ce7b11d7a4fc447014..589f8855305f4eb889d087a745e598d10cfba435 100644 (file)
  * The VRFY and EXPN commands have been removed from this implementation
  * because nobody uses these commands anymore, except for spammers.
  *
- * Copyright (c) 1998-2009 by the citadel.org team
+ * Copyright (c) 1998-2012 by the citadel.org team
  *
- *  This program is free software; you can redistribute it and/or modify
- *  it under the terms of the GNU General Public License as published by
- *  the Free Software Foundation; either version 3 of the License, or
- *  (at your option) any later version.
+ *  This program is open source software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 3.
+ *  
+ *  
  *
  *  This program is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *  GNU General Public License for more details.
  *
- *  You should have received a copy of the GNU General Public License
- *  along with this program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  
+ *  
+ *  
  */
 
 #include "sysdep.h"
@@ -96,3 +96,230 @@ const char *smtp_get_Recipients(void)
                return NULL;
        else return sSMTP->from;
 }
+
+
+/*
+ * smtp_do_bounce() is caled by smtp_do_procmsg() to scan a set of delivery
+ * instructions for "5" codes (permanent fatal errors) and produce/deliver
+ * a "bounce" message (delivery status notification).
+ */
+void smtp_do_bounce(char *instr, StrBuf *OMsgTxt)
+{
+       int i;
+       int lines;
+       int status;
+       char buf[1024];
+       char key[1024];
+       char addr[1024];
+       char dsn[1024];
+       char bounceto[1024];
+       StrBuf *boundary;
+       int num_bounces = 0;
+       int bounce_this = 0;
+       time_t submitted = 0L;
+       struct CtdlMessage *bmsg = NULL;
+       int give_up = 0;
+       struct recptypes *valid;
+       int successful_bounce = 0;
+       static int seq = 0;
+       StrBuf *BounceMB;
+       long omsgid = (-1);
+
+       syslog(LOG_DEBUG, "smtp_do_bounce() called\n");
+       strcpy(bounceto, "");
+       boundary = NewStrBufPlain(HKEY("=_Citadel_Multipart_"));
+
+       StrBufAppendPrintf(boundary,
+                          "%s_%04x%04x",
+                          config.c_fqdn,
+                          getpid(),
+                          ++seq);
+
+       lines = num_tokens(instr, '\n');
+
+       /* See if it's time to give up on delivery of this message */
+       for (i=0; i<lines; ++i) {
+               extract_token(buf, instr, i, '\n', sizeof buf);
+               extract_token(key, buf, 0, '|', sizeof key);
+               extract_token(addr, buf, 1, '|', sizeof addr);
+               if (!strcasecmp(key, "submitted")) {
+                       submitted = atol(addr);
+               }
+       }
+
+       if ( (time(NULL) - submitted) > SMTP_GIVE_UP ) {
+               give_up = 1;
+       }
+
+       /* Start building our bounce message */
+
+       bmsg = (struct CtdlMessage *) malloc(sizeof(struct CtdlMessage));
+       if (bmsg == NULL) return;
+       memset(bmsg, 0, sizeof(struct CtdlMessage));
+       BounceMB = NewStrBufPlain(NULL, 1024);
+
+       bmsg->cm_magic = CTDLMESSAGE_MAGIC;
+       bmsg->cm_anon_type = MES_NORMAL;
+       bmsg->cm_format_type = FMT_RFC822;
+       bmsg->cm_fields['A'] = strdup("Citadel");
+       bmsg->cm_fields['O'] = strdup(MAILROOM);
+       bmsg->cm_fields['N'] = strdup(config.c_nodename);
+       bmsg->cm_fields['U'] = strdup("Delivery Status Notification (Failure)");
+       StrBufAppendBufPlain(
+               BounceMB,
+               HKEY("Content-type: multipart/mixed; boundary=\""), 0);
+       StrBufAppendBuf(BounceMB, boundary, 0);
+       StrBufAppendBufPlain(BounceMB, HKEY("\"\r\n"), 0);
+       StrBufAppendBufPlain(BounceMB, HKEY("MIME-Version: 1.0\r\n"), 0);
+       StrBufAppendBufPlain(BounceMB, HKEY("X-Mailer: " CITADEL "\r\n"), 0);
+
+       StrBufAppendBufPlain(
+               BounceMB,
+               HKEY("\r\nThis is a multipart message in MIME format."
+                    "\r\n\r\n"), 0);
+
+       StrBufAppendBufPlain(BounceMB, HKEY("--"), 0);
+       StrBufAppendBuf(BounceMB, boundary, 0);
+       StrBufAppendBufPlain(BounceMB, HKEY("\r\n"), 0);
+       StrBufAppendBufPlain(BounceMB,
+                            HKEY("Content-type: text/plain\r\n\r\n"), 0);
+
+       if (give_up)
+       {
+               StrBufAppendBufPlain(
+                       BounceMB,
+                       HKEY("A message you sent could not be delivered "
+                            "to some or all of its recipients\ndue to "
+                            "prolonged unavailability of its destination(s).\n"
+                            "Giving up on the following addresses:\n\n"), 0);
+       }
+       else
+       {
+               StrBufAppendBufPlain(
+                       BounceMB,
+                       HKEY("A message you sent could not be delivered "
+                            "to some or all of its recipients.\n"
+                            "The following addresses were undeliverable:\n\n"
+                               ), 0);
+       }
+
+       /*
+        * Now go through the instructions checking for stuff.
+        */
+       for (i=0; i<lines; ++i) {
+               long addrlen;
+               long dsnlen;
+               extract_token(buf, instr, i, '\n', sizeof buf);
+               extract_token(key, buf, 0, '|', sizeof key);
+               addrlen = extract_token(addr, buf, 1, '|', sizeof addr);
+               status = extract_int(buf, 2);
+               dsnlen = extract_token(dsn, buf, 3, '|', sizeof dsn);
+               bounce_this = 0;
+
+               syslog(LOG_DEBUG, "key=<%s> addr=<%s> status=%d dsn=<%s>\n",
+                      key, addr, status, dsn);
+
+               if (!strcasecmp(key, "bounceto")) {
+                       strcpy(bounceto, addr);
+               }
+
+               if (!strcasecmp(key, "msgid")) {
+                       omsgid = atol(addr);
+               }
+
+               if (!strcasecmp(key, "remote")) {
+                       if (status == 5) bounce_this = 1;
+                       if (give_up) bounce_this = 1;
+               }
+
+               if (bounce_this) {
+                       ++num_bounces;
+
+                       StrBufAppendBufPlain(BounceMB, addr, addrlen, 0);
+                       StrBufAppendBufPlain(BounceMB, HKEY(": "), 0);
+                       StrBufAppendBufPlain(BounceMB, dsn, dsnlen, 0);
+                       StrBufAppendBufPlain(BounceMB, HKEY("\r\n"), 0);
+
+                       remove_token(instr, i, '\n');
+                       --i;
+                       --lines;
+               }
+       }
+
+       /* Attach the original message */
+       if (omsgid >= 0) {
+               StrBufAppendBufPlain(BounceMB, HKEY("--"), 0);
+               StrBufAppendBuf(BounceMB, boundary, 0);
+               StrBufAppendBufPlain(BounceMB, HKEY("\r\n"), 0);
+
+               StrBufAppendBufPlain(
+                       BounceMB,
+                       HKEY("Content-type: message/rfc822\r\n"), 0);
+
+               StrBufAppendBufPlain(
+                       BounceMB,
+                       HKEY("Content-Transfer-Encoding: 7bit\r\n"), 0);
+
+               StrBufAppendBufPlain(
+                       BounceMB,
+                       HKEY("Content-Disposition: inline\r\n"), 0);
+
+               StrBufAppendBufPlain(BounceMB, HKEY("\r\n"), 0);
+
+               if (OMsgTxt == NULL) {
+                       CC->redirect_buffer = NewStrBufPlain(NULL, SIZ);
+                       CtdlOutputMsg(omsgid,
+                                     MT_RFC822,
+                                     HEADERS_ALL,
+                                     0, 1, NULL, 0,
+                                     NULL, NULL);
+
+                       StrBufAppendBuf(BounceMB, CC->redirect_buffer, 0);
+                       FreeStrBuf(&CC->redirect_buffer);
+               }
+               else {
+                       StrBufAppendBuf(BounceMB, OMsgTxt, 0);
+               }
+       }
+
+       /* Close the multipart MIME scope */
+       StrBufAppendBufPlain(BounceMB, HKEY("--"), 0);
+       StrBufAppendBuf(BounceMB, boundary, 0);
+       StrBufAppendBufPlain(BounceMB, HKEY("--\r\n"), 0);
+       if (bmsg->cm_fields['A'] != NULL)
+               free(bmsg->cm_fields['A']);
+       bmsg->cm_fields['A'] = SmashStrBuf(&BounceMB);
+       /* Deliver the bounce if there's anything worth mentioning */
+       syslog(LOG_DEBUG, "num_bounces = %d\n", num_bounces);
+       if (num_bounces > 0) {
+
+               /* First try the user who sent the message */
+               if (IsEmptyStr(bounceto))
+                       syslog(LOG_ERR, "No bounce address specified\n");
+               else
+                       syslog(LOG_DEBUG, "bounce to user <%s>\n", bounceto);
+               /* Can we deliver the bounce to the original sender? */
+               valid = validate_recipients(bounceto,
+                                           smtp_get_Recipients (),
+                                           0);
+               if (valid != NULL) {
+                       if (valid->num_error == 0) {
+                               CtdlSubmitMsg(bmsg, valid, "", QP_EADDR);
+                               successful_bounce = 1;
+                       }
+               }
+
+               /* If not, post it in the Aide> room */
+               if (successful_bounce == 0) {
+                       CtdlSubmitMsg(bmsg, NULL, config.c_aideroom, QP_EADDR);
+               }
+
+               /* Free up the memory we used */
+               if (valid != NULL) {
+                       free_recipients(valid);
+               }
+       }
+       FreeStrBuf(&boundary);
+       CtdlFreeMessage(bmsg);
+       syslog(LOG_DEBUG, "Done processing bounces\n");
+}