/*
- * This module is an SMTP and ESMTP implementation for the Citadel system.
- * It is compliant with all of the following:
+ * Utility functions for the Citadel SMTP implementation
*
- * RFC 821 - Simple Mail Transfer Protocol
- * RFC 876 - Survey of SMTP Implementations
- * RFC 1047 - Duplicate messages and SMTP
- * RFC 1652 - 8 bit MIME
- * RFC 1869 - Extended Simple Mail Transfer Protocol
- * RFC 1870 - SMTP Service Extension for Message Size Declaration
- * RFC 2033 - Local Mail Transfer Protocol
- * RFC 2197 - SMTP Service Extension for Command Pipelining
- * RFC 2476 - Message Submission
- * RFC 2487 - SMTP Service Extension for Secure SMTP over TLS
- * RFC 2554 - SMTP Service Extension for Authentication
- * RFC 2821 - Simple Mail Transfer Protocol
- * RFC 2822 - Internet Message Format
- * RFC 2920 - SMTP Service Extension for Command Pipelining
- *
- * The VRFY and EXPN commands have been removed from this implementation
- * because nobody uses these commands anymore, except for spammers.
+ * Copyright (c) 1998-2020 by the citadel.org team
*
- * Copyright (c) 1998-2009 by the citadel.org team
+ * 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 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 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
+ * 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.
*/
#include "sysdep.h"
#include "clientsocket.h"
#include "locate_host.h"
#include "citadel_dirs.h"
-
#include "ctdl_module.h"
-
#include "smtp_util.h"
const char *smtp_get_Recipients(void)
if (sSMTP == NULL)
return NULL;
- else return sSMTP->from;
+ else return ChrPtr(sSMTP->from);
+}
+
+
+/*
+ * smtp_do_bounce() is caled by smtp_process_one_msg() to scan a set of delivery
+ * instructions for errors and produce/deliver a "bounce" message (delivery
+ * status notification).
+ *
+ * is_final should be set to:
+ * SDB_BOUNCE_FATALS Advise the sender of all 5XX (permanent failures)
+ * SDB_BOUNCE_ALL Advise the sender that all deliveries have failed and will not be retried
+ * SDB_WARN Warn the sender about all 4XX transient delays
+ */
+void smtp_do_bounce(const char *instr, int is_final)
+{
+ 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;
+ struct CtdlMessage *bmsg = NULL;
+ recptypes *valid;
+ int successful_bounce = 0;
+ static int seq = 0;
+ StrBuf *BounceMB;
+ long omsgid = (-1);
+
+ syslog(LOG_DEBUG, "smtp_do_bounce() called");
+ strcpy(bounceto, "");
+ boundary = NewStrBufPlain(HKEY("=_Citadel_Multipart_"));
+
+ StrBufAppendPrintf(boundary, "%s_%04x%04x", CtdlGetConfigStr("c_fqdn"), getpid(), ++seq);
+
+
+ /* 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;
+ CM_SetField(bmsg, eAuthor, HKEY("Citadel"));
+ CM_SetField(bmsg, eOriginalRoom, HKEY(MAILROOM));
+ CM_SetField(bmsg, eMsgSubject, HKEY("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 (is_final == SDB_BOUNCE_ALL)
+ {
+ 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 if (is_final == SDB_BOUNCE_FATALS)
+ {
+ 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);
+ }
+ else if (is_final == SDB_WARN)
+ {
+ StrBufAppendBufPlain(
+ BounceMB,
+ HKEY("A message you sent has not been delivered "
+ "to some or all of its recipients.\n"
+ "Citadel will continue attempting delivery for five days.\n"
+ "The following addresses were undeliverable:\n\n"),
+ 0);
+ }
+ else // should never get here
+ {
+ StrBufAppendBufPlain(BounceMB, HKEY("This message should never occur.\n\n"), 0);
+ }
+
+ /*
+ * Now go through the instructions checking for stuff.
+ */
+ lines = num_tokens(instr, '\n');
+ 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>", key, addr, status, dsn);
+
+ if (!strcasecmp(key, "bounceto")) {
+ strcpy(bounceto, addr);
+ }
+
+ if (!strcasecmp(key, "msgid")) {
+ omsgid = atol(addr);
+ }
+
+ if (!strcasecmp(key, "remote")) {
+ if ((is_final == SDB_BOUNCE_FATALS) && (status == 5)) bounce_this = 1;
+ if ((is_final == SDB_BOUNCE_ALL) && (status != 2)) bounce_this = 1;
+ if ((is_final == SDB_WARN) && (status == 4)) 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);
+ }
+ }
+
+ /* 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);
+
+ CC->redirect_buffer = NewStrBufPlain(NULL, SIZ);
+ CtdlOutputMsg(omsgid,
+ MT_RFC822,
+ HEADERS_ALL,
+ 0, 1, NULL, 0,
+ NULL, NULL, NULL
+ );
+ StrBufAppendBuf(BounceMB, CC->redirect_buffer, 0);
+ FreeStrBuf(&CC->redirect_buffer);
+ }
+
+ /* Close the multipart MIME scope */
+ StrBufAppendBufPlain(BounceMB, HKEY("--"), 0);
+ StrBufAppendBuf(BounceMB, boundary, 0);
+ StrBufAppendBufPlain(BounceMB, HKEY("--\r\n"), 0);
+ CM_SetAsFieldSB(bmsg, eMesageText, &BounceMB);
+
+ /* Deliver the bounce if there's anything worth mentioning */
+ syslog(LOG_DEBUG, "num_bounces = %d", num_bounces);
+ if (num_bounces > 0) {
+
+ /* First try the user who sent the message */
+ if (IsEmptyStr(bounceto)) {
+ syslog(LOG_ERR, "No bounce address specified");
+ }
+ else {
+ syslog(LOG_DEBUG, "bounce to user <%s>", 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, "");
+ successful_bounce = 1;
+ }
+ }
+
+ /* If not, post it in the Aide> room */
+ if (successful_bounce == 0) {
+ CtdlSubmitMsg(bmsg, NULL, CtdlGetConfigStr("c_aideroom"));
+ }
+
+ /* Free up the memory we used */
+ if (valid != NULL) {
+ free_recipients(valid);
+ }
+ }
+ FreeStrBuf(&boundary);
+ CM_Free(bmsg);
+ syslog(LOG_DEBUG, "Done processing bounces");
}
+
+
+
+
+
+char *smtpcodes[][2] = {
+ { "211 - System status / system help reply" },
+ { "214", "Help message" },
+ { "220", "Domain service ready" },
+ { "221", "Domain service closing transmission channel" },
+ { "250", "Requested mail action completed and OK" },
+ { "251", "Not Local User, forward email to forward path" },
+ { "252", "Cannot Verify user, will attempt delivery later" },
+ { "253", "Pending messages for node started" },
+ { "354", "Start mail input; end with ." },
+ { "355", "Octet-offset is the transaction offset" },
+ { "421", "Domain service not available, closing transmission channel" },
+ { "432", "Domain service not available, closing transmission channel" },
+ { "450", "Requested mail action not taken: mailbox unavailable. request refused" },
+ { "451", "Requested action aborted: local error in processing Request is unable to be processed, try again" },
+ { "452", "Requested action not taken: insufficient system storage" },
+ { "453", "No mail" },
+ { "454", "TLS not available due to temporary reason. Encryption required for requested authentication mechanism" },
+ { "458", "Unable to queue messages for node" },
+ { "459", "Node not allowed: reason" },
+ { "500", "Syntax error, command unrecognized" },
+ { "501", "Syntax error in parameters or arguments" },
+ { "502", "Command not implemented" },
+ { "503", "Bad sequence of commands" },
+ { "504", "Command parameter not implemented" },
+ { "510", "Check the recipient address" },
+ { "512", "Domain can not be found. Unknown host." },
+ { "515", "Destination mailbox address invalid" },
+ { "517", "Problem with senders mail attribute, check properties" },
+ { "521", "Domain does not accept mail" },
+ { "522", "Recipient has exceeded mailbox limit" },
+ { "523", "Server limit exceeded. Message too large" },
+ { "530", "Access Denied. Authentication required" },
+ { "531", "Mail system Full" },
+ { "533", "Remote server has insufficient disk space to hold email" },
+ { "534", "Authentication mechanism is too weak. Message too big" },
+ { "535", "Multiple servers using same IP. Required Authentication" },
+ { "538", "Encryption required for requested authentication mechanism" },
+ { "540", "Email address has no DNS Server" },
+ { "541", "No response from host" },
+ { "542", "Bad Connection" },
+ { "543", "Routing server failure. No available route" },
+ { "546", "Email looping" },
+ { "547", "Delivery time-out" },
+ { "550", "Requested action not taken: mailbox unavailable or relaying denied" },
+ { "551", "User not local; please try forward path" },
+ { "552", "Requested mail action aborted: exceeded storage allocation" },
+ { "553", "Requested action not taken: mailbox name not allowed" },
+ { "554", "Transaction failed" }
+};
+
+
+
+char *smtpstatus(int code) {
+ int i;
+
+ for (i=0; i<(sizeof(smtpcodes)/sizeof(char *)/2); ++i) {
+ if (atoi(smtpcodes[i][0]) == code) {
+ return(smtpcodes[i][1]);
+ }
+ }
+
+ return("Unknown or other SMTP status");
+}
+
projects / citadel.git / blobdiff