/*
- * 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) 1998-2015 by the citadel.org team
+ * Copyright (c) 1998-2020 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.
#include <errno.h>
#include <sys/types.h>
#include <syslog.h>
-
-#if TIME_WITH_SYS_TIME
-# include <sys/time.h>
-# include <time.h>
-#else
-# if HAVE_SYS_TIME_H
-# include <sys/time.h>
-# else
-# include <time.h>
-# endif
-#endif
-
+#include <time.h>
#include <sys/wait.h>
#include <ctype.h>
#include <string.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)
/*
- * 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).
+ * 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(char *instr, StrBuf *OMsgTxt)
+void smtp_do_bounce(const char *instr, int is_final)
{
int i;
int lines;
StrBuf *boundary;
int num_bounces = 0;
int bounce_this = 0;
- time_t submitted = 0L;
struct CtdlMessage *bmsg = NULL;
- int give_up = 0;
- recptypes *valid;
+ struct recptypes *valid;
int successful_bounce = 0;
static int seq = 0;
StrBuf *BounceMB;
long omsgid = (-1);
- syslog(LOG_DEBUG, "smtp_do_bounce() called\n");
+ syslog(LOG_DEBUG, "smtp_do_bounce() called");
strcpy(bounceto, "");
boundary = NewStrBufPlain(HKEY("=_Citadel_Multipart_"));
StrBufAppendPrintf(boundary, "%s_%04x%04x", CtdlGetConfigStr("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->cm_format_type = FMT_RFC822;
CM_SetField(bmsg, eAuthor, HKEY("Citadel"));
CM_SetField(bmsg, eOriginalRoom, HKEY(MAILROOM));
- CM_SetField(bmsg, eNodeName, CtdlGetConfigStr("c_nodename"), strlen(CtdlGetConfigStr("c_nodename")));
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("\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);
+ StrBufAppendBufPlain(BounceMB, HKEY("Content-type: text/plain\r\n\r\n"), 0);
- if (give_up)
+ 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\ndue to "
- "prolonged unavailability of its destination(s).\n"
- "Giving up on the following addresses:\n\n"), 0);
+ 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
+ else if (is_final == SDB_WARN)
{
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);
+ 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;
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);
+ 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, "remote")) {
- if (status == 5) bounce_this = 1;
- if (give_up) bounce_this = 1;
+ 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);
-
- remove_token(instr, i, '\n');
- --i;
- --lines;
}
}
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("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, NULL);
-
- StrBufAppendBuf(BounceMB, CC->redirect_buffer, 0);
- FreeStrBuf(&CC->redirect_buffer);
- }
- else {
- StrBufAppendBuf(BounceMB, OMsgTxt, 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 */
CM_SetAsFieldSB(bmsg, eMesageText, &BounceMB);
/* Deliver the bounce if there's anything worth mentioning */
- syslog(LOG_DEBUG, "num_bounces = %d\n", num_bounces);
+ 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\n");
- else
- syslog(LOG_DEBUG, "bounce to user <%s>\n", bounceto);
+ 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);
+ valid = validate_recipients(bounceto, smtp_get_Recipients (), 0);
if (valid != NULL) {
if (valid->num_error == 0) {
- CtdlSubmitMsg(bmsg, valid, "", QP_EADDR);
+ CtdlSubmitMsg(bmsg, valid, "");
successful_bounce = 1;
}
}
/* If not, post it in the Aide> room */
if (successful_bounce == 0) {
- CtdlSubmitMsg(bmsg, NULL, CtdlGetConfigStr("c_aideroom"), QP_EADDR);
+ CtdlSubmitMsg(bmsg, NULL, CtdlGetConfigStr("c_aideroom"));
}
/* Free up the memory we used */
}
FreeStrBuf(&boundary);
CM_Free(bmsg);
- syslog(LOG_DEBUG, "Done processing bounces\n");
+ 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");
+}
+