2 * This module is an SMTP and ESMTP server for the Citadel system.
3 * It is compliant with all of the following:
5 * RFC 821 - Simple Mail Transfer Protocol
6 * RFC 876 - Survey of SMTP Implementations
7 * RFC 1047 - Duplicate messages and SMTP
8 * RFC 1652 - 8 bit MIME
9 * RFC 1869 - Extended Simple Mail Transfer Protocol
10 * RFC 1870 - SMTP Service Extension for Message Size Declaration
11 * RFC 2033 - Local Mail Transfer Protocol
12 * RFC 2197 - SMTP Service Extension for Command Pipelining
13 * RFC 2476 - Message Submission
14 * RFC 2487 - SMTP Service Extension for Secure SMTP over TLS
15 * RFC 2554 - SMTP Service Extension for Authentication
16 * RFC 2821 - Simple Mail Transfer Protocol
17 * RFC 2822 - Internet Message Format
18 * RFC 2920 - SMTP Service Extension for Command Pipelining
20 * The VRFY and EXPN commands have been removed from this implementation
21 * because nobody uses these commands anymore, except for spammers.
23 * Copyright (c) 1998-2012 by the citadel.org team
25 * This program is open source software; you can redistribute it and/or modify
26 * it under the terms of the GNU General Public License version 3.
28 * This program is distributed in the hope that it will be useful,
29 * but WITHOUT ANY WARRANTY; without even the implied warranty of
30 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
31 * GNU General Public License for more details.
43 #include <sys/types.h>
46 #if TIME_WITH_SYS_TIME
47 # include <sys/time.h>
51 # include <sys/time.h>
61 #include <sys/socket.h>
62 #include <netinet/in.h>
63 #include <arpa/inet.h>
64 #include <libcitadel.h>
67 #include "citserver.h"
74 #include "internet_addressing.h"
77 #include "clientsocket.h"
78 #include "locate_host.h"
79 #include "citadel_dirs.h"
80 #include "ctdl_module.h"
82 #include "smtp_util.h"
83 enum { /* Command states for login authentication */
96 typedef void (*smtp_handler)(long offest, long Flags);
98 typedef struct _smtp_handler_hook {
103 HashList *SMTPCmds = NULL;
104 #define MaxSMTPCmdLen 10
106 #define RegisterSmtpCMD(First, H, Flags) \
107 registerSmtpCMD(HKEY(First), H, Flags)
108 void registerSmtpCMD(const char *First, long FLen,
112 smtp_handler_hook *h;
114 if (FLen >= MaxSMTPCmdLen)
115 cit_panic_backtrace (0);
117 h = (smtp_handler_hook*) malloc(sizeof(smtp_handler_hook));
118 memset(h, 0, sizeof(smtp_handler_hook));
122 Put(SMTPCmds, First, FLen, h, NULL);
125 void smtp_cleanup(void)
127 DeleteHash(&SMTPCmds);
131 * Here's where our SMTP session begins its happy day.
133 void smtp_greeting(int is_msa)
136 char message_to_spammer[1024];
138 strcpy(CC->cs_clientname, "SMTP session");
139 CC->internal_pgm = 1;
140 CC->cs_flags |= CS_STEALTH;
141 CC->session_specific_data = malloc(sizeof(citsmtp));
142 memset(SMTP, 0, sizeof(citsmtp));
144 sSMTP->is_msa = is_msa;
145 sSMTP->Cmd = NewStrBufPlain(NULL, SIZ);
146 sSMTP->helo_node = NewStrBuf();
147 sSMTP->from = NewStrBufPlain(NULL, SIZ);
148 sSMTP->recipients = NewStrBufPlain(NULL, SIZ);
149 sSMTP->OneRcpt = NewStrBufPlain(NULL, SIZ);
151 /* If this config option is set, reject connections from problem
152 * addresses immediately instead of after they execute a RCPT
154 if ( (config.c_rbl_at_greeting) && (sSMTP->is_msa == 0) ) {
155 if (rbl_check(message_to_spammer)) {
156 if (server_shutting_down)
157 cprintf("421 %s\r\n", message_to_spammer);
159 cprintf("550 %s\r\n", message_to_spammer);
160 CC->kill_me = KILLME_SPAMMER;
161 /* no need to free_recipients(valid), it's not allocated yet */
166 /* Otherwise we're either clean or we check later. */
168 if (CC->nologin==1) {
169 cprintf("451 Too many connections are already open; please try again later.\r\n");
170 CC->kill_me = KILLME_MAX_SESSIONS_EXCEEDED;
171 /* no need to free_recipients(valid), it's not allocated yet */
175 /* Note: the FQDN *must* appear as the first thing after the 220 code.
176 * Some clients (including citmail.c) depend on it being there.
178 cprintf("220 %s ESMTP Citadel server ready.\r\n", config.c_fqdn);
183 * SMTPS is just like SMTP, except it goes crypto right away.
185 void smtps_greeting(void) {
186 CtdlModuleStartCryptoMsgs(NULL, NULL, NULL);
188 if (!CC->redirect_ssl) CC->kill_me = KILLME_NO_CRYPTO; /* kill session if no crypto */
195 * SMTP MSA port requires authentication.
197 void smtp_msa_greeting(void) {
203 * LMTP is like SMTP but with some extra bonus footage added.
205 void lmtp_greeting(void) {
213 * Generic SMTP MTA greeting
215 void smtp_mta_greeting(void) {
221 * We also have an unfiltered LMTP socket that bypasses spam filters.
223 void lmtp_unfiltered_greeting(void) {
229 sSMTP->is_unfiltered = 1;
234 * Login greeting common to all auth methods
236 void smtp_auth_greeting(long offset, long Flags) {
237 cprintf("235 Hello, %s\r\n", CC->user.fullname);
238 syslog(LOG_NOTICE, "SMTP authenticated %s\n", CC->user.fullname);
239 CC->internal_pgm = 0;
240 CC->cs_flags &= ~CS_STEALTH;
245 * Implement HELO and EHLO commands.
247 * which_command: 0=HELO, 1=EHLO, 2=LHLO
249 void smtp_hello(long offset, long which_command)
251 citsmtp *sSMTP = SMTP;
253 StrBufAppendBuf (sSMTP->helo_node, sSMTP->Cmd, offset);
255 if ( (which_command != LHLO) && (sSMTP->is_lmtp) ) {
256 cprintf("500 Only LHLO is allowed when running LMTP\r\n");
260 if ( (which_command == LHLO) && (sSMTP->is_lmtp == 0) ) {
261 cprintf("500 LHLO is only allowed when running LMTP\r\n");
265 if (which_command == HELO) {
266 cprintf("250 Hello %s (%s [%s])\r\n",
267 ChrPtr(sSMTP->helo_node),
273 if (which_command == EHLO) {
274 cprintf("250-Hello %s (%s [%s])\r\n",
275 ChrPtr(sSMTP->helo_node),
281 cprintf("250-Greetings and joyous salutations.\r\n");
283 cprintf("250-HELP\r\n");
284 cprintf("250-SIZE %ld\r\n", config.c_maxmsglen);
288 * Offer TLS, but only if TLS is not already active.
289 * Furthermore, only offer TLS when running on
290 * the SMTP-MSA port, not on the SMTP-MTA port, due to
291 * questionable reliability of TLS in certain sending MTA's.
293 if ( (!CC->redirect_ssl) && (sSMTP->is_msa) ) {
294 cprintf("250-STARTTLS\r\n");
296 #endif /* HAVE_OPENSSL */
298 cprintf("250-AUTH LOGIN PLAIN\r\n"
299 "250-AUTH=LOGIN PLAIN\r\n"
308 * Implement HELP command.
310 void smtp_help(long offset, long Flags) {
311 cprintf("214 RTFM http://www.ietf.org/rfc/rfc2821.txt\r\n");
318 void smtp_get_user(long offset)
322 citsmtp *sSMTP = SMTP;
324 CtdlDecodeBase64(username, ChrPtr(sSMTP->Cmd) + offset, SIZ);
325 /* syslog(LOG_DEBUG, "Trying <%s>\n", username); */
326 if (CtdlLoginExistingUser(NULL, username) == login_ok) {
327 CtdlEncodeBase64(buf, "Password:", 9, 0);
328 cprintf("334 %s\r\n", buf);
329 sSMTP->command_state = smtp_password;
332 cprintf("500 No such user.\r\n");
333 sSMTP->command_state = smtp_command;
341 void smtp_get_pass(long offset, long Flags)
343 citsmtp *sSMTP = SMTP;
347 memset(password, 0, sizeof(password));
348 len = CtdlDecodeBase64(password, ChrPtr(sSMTP->Cmd), SIZ);
349 /* syslog(LOG_DEBUG, "Trying <%s>\n", password); */
350 if (CtdlTryPassword(password, len) == pass_ok) {
351 smtp_auth_greeting(offset, Flags);
354 cprintf("535 Authentication failed.\r\n");
356 sSMTP->command_state = smtp_command;
361 * Back end for PLAIN auth method (either inline or multistate)
363 void smtp_try_plain(long offset, long Flags)
365 citsmtp *sSMTP = SMTP;
366 char decoded_authstring[1024];
373 CtdlDecodeBase64(decoded_authstring, ChrPtr(sSMTP->Cmd), StrLength(sSMTP->Cmd));
374 safestrncpy(ident, decoded_authstring, sizeof ident);
375 safestrncpy(user, &decoded_authstring[strlen(ident) + 1], sizeof user);
376 len = safestrncpy(pass, &decoded_authstring[strlen(ident) + strlen(user) + 2], sizeof pass);
378 len = sizeof(pass) - 1;
380 sSMTP->command_state = smtp_command;
382 if (!IsEmptyStr(ident)) {
383 result = CtdlLoginExistingUser(user, ident);
386 result = CtdlLoginExistingUser(NULL, user);
389 if (result == login_ok) {
390 if (CtdlTryPassword(pass, len) == pass_ok) {
391 smtp_auth_greeting(offset, Flags);
395 cprintf("504 Authentication failed.\r\n");
400 * Attempt to perform authenticated SMTP
402 void smtp_auth(long offset, long Flags)
404 citsmtp *sSMTP = SMTP;
405 char username_prompt[64];
407 char encoded_authstring[1024];
410 cprintf("504 Already logged in.\r\n");
414 extract_token(method, ChrPtr(sSMTP->Cmd), 0, ' ', sizeof method);
416 if (!strncasecmp(method, "login", 5) ) {
417 if (StrLength(sSMTP->Cmd) >= 7) {
421 CtdlEncodeBase64(username_prompt, "Username:", 9, 0);
422 cprintf("334 %s\r\n", username_prompt);
423 sSMTP->command_state = smtp_user;
428 if (!strncasecmp(method, "plain", 5) ) {
430 if (num_tokens(ChrPtr(sSMTP->Cmd), ' ') < 2) {
432 SMTP->command_state = smtp_plain;
436 len = extract_token(encoded_authstring,
439 sizeof encoded_authstring);
440 StrBufPlain(sSMTP->Cmd, encoded_authstring, len);
441 smtp_try_plain(offset, Flags);
445 if (strncasecmp(method, "login", 5) ) {
446 cprintf("504 Unknown authentication method.\r\n");
454 * Implements the RSET (reset state) command.
455 * Currently this just zeroes out the state buffer. If pointers to data
456 * allocated with malloc() are ever placed in the state buffer, we have to
457 * be sure to free() them first!
459 * Set do_response to nonzero to output the SMTP RSET response code.
461 void smtp_rset(long offset, long do_response) {
464 citsmtp *sSMTP = SMTP;
467 * Our entire SMTP state is discarded when a RSET command is issued,
468 * but we need to preserve this one little piece of information, so
469 * we save it for later.
471 is_lmtp = sSMTP->is_lmtp;
472 is_unfiltered = sSMTP->is_unfiltered;
474 memset(sSMTP, 0, sizeof(citsmtp));
477 * It is somewhat ambiguous whether we want to log out when a RSET
478 * command is issued. Here's the code to do it. It is commented out
479 * because some clients (such as Pine) issue RSET commands before
480 * each message, but still expect to be logged in.
482 * if (CC->logged_in) {
488 * Reinstate this little piece of information we saved (see above).
490 sSMTP->is_lmtp = is_lmtp;
491 sSMTP->is_unfiltered = is_unfiltered;
494 cprintf("250 Zap!\r\n");
499 * Clear out the portions of the state buffer that need to be cleared out
500 * after the DATA command finishes.
502 void smtp_data_clear(long offset, long flags)
504 citsmtp *sSMTP = SMTP;
506 FlushStrBuf(sSMTP->from);
507 FlushStrBuf(sSMTP->recipients);
508 FlushStrBuf(sSMTP->OneRcpt);
509 sSMTP->number_of_recipients = 0;
510 sSMTP->delivery_mode = 0;
511 sSMTP->message_originated_locally = 0;
515 * Implements the "MAIL FROM:" command
517 void smtp_mail(long offset, long flags) {
521 citsmtp *sSMTP = SMTP;
523 if (StrLength(sSMTP->from) > 0) {
524 cprintf("503 Only one sender permitted\r\n");
528 if (strncasecmp(ChrPtr(sSMTP->Cmd) + offset, "From:", 5)) {
529 cprintf("501 Syntax error\r\n");
533 StrBufAppendBuf(sSMTP->from, sSMTP->Cmd, offset);
534 StrBufTrim(sSMTP->from);
535 if (strchr(ChrPtr(sSMTP->from), '<') != NULL) {
536 StrBufStripAllBut(sSMTP->from, '<', '>');
539 /* We used to reject empty sender names, until it was brought to our
540 * attention that RFC1123 5.2.9 requires that this be allowed. So now
541 * we allow it, but replace the empty string with a fake
542 * address so we don't have to contend with the empty string causing
543 * other code to fail when it's expecting something there.
545 if (StrLength(sSMTP->from)) {
546 StrBufPlain(sSMTP->from, HKEY("someone@example.com"));
549 /* If this SMTP connection is from a logged-in user, force the 'from'
550 * to be the user's Internet e-mail address as Citadel knows it.
553 StrBufPlain(sSMTP->from, CC->cs_inet_email, -1);
554 cprintf("250 Sender ok <%s>\r\n", ChrPtr(sSMTP->from));
555 sSMTP->message_originated_locally = 1;
559 else if (sSMTP->is_lmtp) {
560 /* Bypass forgery checking for LMTP */
563 /* Otherwise, make sure outsiders aren't trying to forge mail from
564 * this system (unless, of course, c_allow_spoofing is enabled)
566 else if (config.c_allow_spoofing == 0) {
567 process_rfc822_addr(ChrPtr(sSMTP->from), user, node, name);
568 if (CtdlHostAlias(node) != hostalias_nomatch) {
569 cprintf("550 You must log in to send mail from %s\r\n", node);
570 FlushStrBuf(sSMTP->from);
575 cprintf("250 Sender ok\r\n");
581 * Implements the "RCPT To:" command
583 void smtp_rcpt(long offset, long flags)
585 struct CitContext *CCC = CC;
586 char message_to_spammer[SIZ];
587 struct recptypes *valid = NULL;
588 citsmtp *sSMTP = SMTP;
590 if (StrLength(sSMTP->from) == 0) {
591 cprintf("503 Need MAIL before RCPT\r\n");
595 if (strncasecmp(ChrPtr(sSMTP->Cmd) + offset, "To:", 3)) {
596 cprintf("501 Syntax error\r\n");
600 if ( (sSMTP->is_msa) && (!CCC->logged_in) ) {
601 cprintf("550 You must log in to send mail on this port.\r\n");
602 FlushStrBuf(sSMTP->from);
605 FlushStrBuf(sSMTP->OneRcpt);
606 StrBufAppendBuf(sSMTP->OneRcpt, sSMTP->Cmd, offset + 3);
607 StrBufTrim(sSMTP->OneRcpt);
608 StrBufStripAllBut(sSMTP->OneRcpt, '<', '>');
610 if ( (StrLength(sSMTP->OneRcpt) + StrLength(sSMTP->recipients)) >= SIZ) {
611 cprintf("452 Too many recipients\r\n");
616 if ( (!CCC->logged_in) /* Don't RBL authenticated users */
617 && (!sSMTP->is_lmtp) ) { /* Don't RBL LMTP clients */
618 if (config.c_rbl_at_greeting == 0) { /* Don't RBL again if we already did it */
619 if (rbl_check(message_to_spammer)) {
620 if (server_shutting_down)
621 cprintf("421 %s\r\n", message_to_spammer);
623 cprintf("550 %s\r\n", message_to_spammer);
624 /* no need to free_recipients(valid), it's not allocated yet */
630 valid = validate_recipients(
631 ChrPtr(sSMTP->OneRcpt),
632 smtp_get_Recipients(),
633 (sSMTP->is_lmtp)? POST_LMTP: (CCC->logged_in)? POST_LOGGED_IN: POST_EXTERNAL
635 if (valid->num_error != 0) {
636 cprintf("550 %s\r\n", valid->errormsg);
637 free_recipients(valid);
641 if (valid->num_internet > 0) {
642 if (CCC->logged_in) {
643 if (CtdlCheckInternetMailPermission(&CCC->user)==0) {
644 cprintf("551 <%s> - you do not have permission to send Internet mail\r\n",
645 ChrPtr(sSMTP->OneRcpt));
646 free_recipients(valid);
652 if (valid->num_internet > 0) {
653 if ( (sSMTP->message_originated_locally == 0)
654 && (sSMTP->is_lmtp == 0) ) {
655 cprintf("551 <%s> - relaying denied\r\n", ChrPtr(sSMTP->OneRcpt));
656 free_recipients(valid);
661 cprintf("250 RCPT ok <%s>\r\n", ChrPtr(sSMTP->OneRcpt));
662 if (StrLength(sSMTP->recipients) > 0) {
663 StrBufAppendBufPlain(sSMTP->recipients, HKEY(","), 0);
665 StrBufAppendBuf(sSMTP->recipients, sSMTP->OneRcpt, 0);
666 sSMTP->number_of_recipients ++;
668 free_recipients(valid);
676 * Implements the DATA command
678 void smtp_data(long offset, long flags)
680 struct CitContext *CCC = CC;
683 struct CtdlMessage *msg = NULL;
686 struct recptypes *valid;
689 citsmtp *sSMTP = SMTP;
691 if (StrLength(sSMTP->from) == 0) {
692 cprintf("503 Need MAIL command first.\r\n");
696 if (sSMTP->number_of_recipients < 1) {
697 cprintf("503 Need RCPT command first.\r\n");
701 cprintf("354 Transmit message now - terminate with '.' by itself\r\n");
703 datestring(nowstamp, sizeof nowstamp, time(NULL), DATESTRING_RFC822);
704 defbody = NewStrBufPlain(NULL, SIZ);
706 if (defbody != NULL) {
707 if (sSMTP->is_lmtp && (CCC->cs_UDSclientUID != -1)) {
710 "Received: from %s (Citadel from userid %ld)\n"
712 ChrPtr(sSMTP->helo_node),
713 (long int) CCC->cs_UDSclientUID,
720 "Received: from %s (%s [%s])\n"
722 ChrPtr(sSMTP->helo_node),
729 body = CtdlReadMessageBodyBuf(HKEY("."), config.c_maxmsglen, defbody, 1, NULL);
730 FreeStrBuf(&defbody);
732 cprintf("550 Unable to save message: internal error.\r\n");
736 syslog(LOG_DEBUG, "Converting message...\n");
737 msg = convert_internet_message_buf(&body);
739 /* If the user is locally authenticated, FORCE the From: header to
740 * show up as the real sender. Yes, this violates the RFC standard,
741 * but IT MAKES SENSE. If you prefer strict RFC adherence over
742 * common sense, you can disable this in the configuration.
744 * We also set the "message room name" ('O' field) to MAILROOM
745 * (which is Mail> on most systems) to prevent it from getting set
746 * to something ugly like "0000058008.Sent Items>" when the message
747 * is read with a Citadel client.
749 if ( (CCC->logged_in) && (config.c_rfc822_strict_from != CFG_SMTP_FROM_NOFILTER) ) {
752 if (!IsEmptyStr(msg->cm_fields['F']) &&
753 ((config.c_rfc822_strict_from == CFG_SMTP_FROM_CORRECT) ||
754 (config.c_rfc822_strict_from == CFG_SMTP_FROM_REJECT) ) )
756 if (!IsEmptyStr(CCC->cs_inet_email))
757 validemail = strcmp(CCC->cs_inet_email, msg->cm_fields['F']) == 0;
759 (!IsEmptyStr(CCC->cs_inet_other_emails)))
761 int num_secondary_emails = 0;
763 num_secondary_emails = num_tokens(CCC->cs_inet_other_emails, '|');
764 for (i=0; i < num_secondary_emails && !validemail; ++i) {
766 extract_token(buf, CCC->cs_inet_other_emails,i,'|',sizeof CCC->cs_inet_other_emails);
767 validemail = strcmp(buf, msg->cm_fields['F']) == 0;
772 if (!validemail && (config.c_rfc822_strict_from == CFG_SMTP_FROM_REJECT)) {
773 syslog(LOG_ERR, "invalid sender '%s' - rejecting this message", msg->cm_fields['F']);
774 cprintf("550 Invalid sender '%s' - rejecting this message.\r\n", msg->cm_fields['F']);
778 if (msg->cm_fields['A'] != NULL) free(msg->cm_fields['A']);
779 if (msg->cm_fields['N'] != NULL) free(msg->cm_fields['N']);
780 if (msg->cm_fields['H'] != NULL) free(msg->cm_fields['H']);
781 if (msg->cm_fields['O'] != NULL) free(msg->cm_fields['O']);
782 msg->cm_fields['A'] = strdup(CCC->user.fullname);
783 msg->cm_fields['N'] = strdup(config.c_nodename);
784 msg->cm_fields['H'] = strdup(config.c_humannode);
785 msg->cm_fields['O'] = strdup(MAILROOM);
788 if (msg->cm_fields['F'] != NULL) free(msg->cm_fields['F']);
789 msg->cm_fields['F'] = strdup(CCC->cs_inet_email);
793 /* Set the "envelope from" address */
794 if (msg->cm_fields['P'] != NULL) {
795 free(msg->cm_fields['P']);
797 msg->cm_fields['P'] = strdup(ChrPtr(sSMTP->from));
799 /* Set the "envelope to" address */
800 if (msg->cm_fields['V'] != NULL) {
801 free(msg->cm_fields['V']);
803 msg->cm_fields['V'] = strdup(ChrPtr(sSMTP->recipients));
805 /* Submit the message into the Citadel system. */
806 valid = validate_recipients(
807 ChrPtr(sSMTP->recipients),
808 smtp_get_Recipients(),
809 (sSMTP->is_lmtp)? POST_LMTP: (CCC->logged_in)? POST_LOGGED_IN: POST_EXTERNAL
812 /* If there are modules that want to scan this message before final
813 * submission (such as virus checkers or spam filters), call them now
814 * and give them an opportunity to reject the message.
816 if (sSMTP->is_unfiltered) {
820 scan_errors = PerformMessageHooks(msg, EVT_SMTPSCAN);
823 if (scan_errors > 0) { /* We don't want this message! */
825 if (msg->cm_fields['0'] == NULL) {
826 msg->cm_fields['0'] = strdup("Message rejected by filter");
829 StrBufPrintf(sSMTP->OneRcpt, "550 %s\r\n", msg->cm_fields['0']);
832 else { /* Ok, we'll accept this message. */
833 msgnum = CtdlSubmitMsg(msg, valid, "", 0);
835 StrBufPrintf(sSMTP->OneRcpt, "250 Message accepted.\r\n");
838 StrBufPrintf(sSMTP->OneRcpt, "550 Internal delivery error\r\n");
842 /* For SMTP and ESMTP, just print the result message. For LMTP, we
843 * have to print one result message for each recipient. Since there
844 * is nothing in Citadel which would cause different recipients to
845 * have different results, we can get away with just spitting out the
846 * same message once for each recipient.
848 if (sSMTP->is_lmtp) {
849 for (i=0; i<sSMTP->number_of_recipients; ++i) {
850 cputbuf(sSMTP->OneRcpt);
854 cputbuf(sSMTP->OneRcpt);
857 /* Write something to the syslog(which may or may not be where the
858 * rest of the Citadel logs are going; some sysadmins want LOG_MAIL).
860 syslog((LOG_MAIL | LOG_INFO),
861 "%ld: from=<%s>, nrcpts=%d, relay=%s [%s], stat=%s",
864 sSMTP->number_of_recipients,
867 ChrPtr(sSMTP->OneRcpt)
871 CtdlFreeMessage(msg);
872 free_recipients(valid);
873 smtp_data_clear(0, 0); /* clear out the buffers now */
878 * implements the STARTTLS command
880 void smtp_starttls(long offset, long flags)
882 char ok_response[SIZ];
883 char nosup_response[SIZ];
884 char error_response[SIZ];
886 sprintf(ok_response, "220 Begin TLS negotiation now\r\n");
887 sprintf(nosup_response, "554 TLS not supported here\r\n");
888 sprintf(error_response, "554 Internal error\r\n");
889 CtdlModuleStartCryptoMsgs(ok_response, nosup_response, error_response);
895 * Main command loop for SMTP server sessions.
897 void smtp_command_loop(void)
899 struct CitContext *CCC = CC;
900 citsmtp *sSMTP = SMTP;
901 const char *pch, *pchs;
903 char CMD[MaxSMTPCmdLen + 1];
906 syslog(LOG_EMERG, "Session SMTP data is null. WTF? We will crash now.\n");
907 return cit_panic_backtrace (0);
911 if (CtdlClientGetLine(sSMTP->Cmd) < 1) {
912 syslog(LOG_CRIT, "SMTP: client disconnected: ending session.\n");
913 CC->kill_me = KILLME_CLIENT_DISCONNECTED;
916 syslog(LOG_DEBUG, "SMTP server: %s\n", ChrPtr(sSMTP->Cmd));
918 if (sSMTP->command_state == smtp_user) {
922 else if (sSMTP->command_state == smtp_password) {
926 else if (sSMTP->command_state == smtp_plain) {
927 smtp_try_plain(0, 0);
930 pchs = pch = ChrPtr(sSMTP->Cmd);
932 while ((*pch != '\0') &&
934 (pch - pchs <= MaxSMTPCmdLen))
936 CMD[i] = toupper(*pch);
942 if ((*pch == '\0') ||
947 if (GetHash(SMTPCmds, CMD, i, &v) &&
950 smtp_handler_hook *h = (smtp_handler_hook*) v;
952 if (isblank(pchs[i]))
960 cprintf("502 I'm afraid I can't do that.\r\n");
963 void smtp_noop(long offest, long Flags)
965 cprintf("250 NOOP\r\n");
968 void smtp_quit(long offest, long Flags)
970 cprintf("221 Goodbye...\r\n");
971 CC->kill_me = KILLME_CLIENT_LOGGED_OUT;
974 /*****************************************************************************/
975 /* MODULE INITIALIZATION STUFF */
976 /*****************************************************************************/
978 * This cleanup function blows away the temporary memory used by
981 void smtp_cleanup_function(void)
983 citsmtp *sSMTP = SMTP;
985 /* Don't do this stuff if this is not an SMTP session! */
986 if (CC->h_command_function != smtp_command_loop) return;
988 syslog(LOG_DEBUG, "Performing SMTP cleanup hook\n");
990 FreeStrBuf(&sSMTP->Cmd);
991 FreeStrBuf(&sSMTP->helo_node);
992 FreeStrBuf(&sSMTP->from);
993 FreeStrBuf(&sSMTP->recipients);
994 FreeStrBuf(&sSMTP->OneRcpt);
999 const char *CitadelServiceSMTP_MTA="SMTP-MTA";
1000 const char *CitadelServiceSMTPS_MTA="SMTPs-MTA";
1001 const char *CitadelServiceSMTP_MSA="SMTP-MSA";
1002 const char *CitadelServiceSMTP_LMTP="LMTP";
1003 const char *CitadelServiceSMTP_LMTP_UNF="LMTP-UnF";
1005 CTDL_MODULE_INIT(smtp)
1009 SMTPCmds = NewHash(1, NULL);
1010 RegisterSmtpCMD("AUTH", smtp_auth, 0);
1011 RegisterSmtpCMD("DATA", smtp_data, 0);
1012 RegisterSmtpCMD("HELO", smtp_hello, HELO);
1013 RegisterSmtpCMD("EHLO", smtp_hello, EHLO);
1014 RegisterSmtpCMD("LHLO", smtp_hello, LHLO);
1015 RegisterSmtpCMD("HELP", smtp_help, 0);
1016 RegisterSmtpCMD("MAIL", smtp_mail, 0);
1017 RegisterSmtpCMD("NOOP", smtp_noop, 0);
1018 RegisterSmtpCMD("QUIT", smtp_quit, 0);
1019 RegisterSmtpCMD("RCPT", smtp_rcpt, 0);
1020 RegisterSmtpCMD("RSET", smtp_rset, 1);
1022 RegisterSmtpCMD("STARTTLS", smtp_starttls, 0);
1026 CtdlRegisterServiceHook(config.c_smtp_port, /* SMTP MTA */
1031 CitadelServiceSMTP_MTA);
1034 CtdlRegisterServiceHook(config.c_smtps_port,
1039 CitadelServiceSMTPS_MTA);
1042 CtdlRegisterServiceHook(config.c_msa_port, /* SMTP MSA */
1047 CitadelServiceSMTP_MSA);
1049 CtdlRegisterServiceHook(0, /* local LMTP */
1054 CitadelServiceSMTP_LMTP);
1056 CtdlRegisterServiceHook(0, /* local LMTP */
1057 file_lmtp_unfiltered_socket,
1058 lmtp_unfiltered_greeting,
1061 CitadelServiceSMTP_LMTP_UNF);
1063 CtdlRegisterSessionHook(smtp_cleanup_function, EVT_STOP, PRIO_STOP + 250);
1066 /* return our module name for the log */