citadel/modules/smtp/serv_smtp.c

   1 /*
   2  * $Id$
   3  *
   4  * This module is an SMTP and ESMTP implementation for the Citadel system.
   5  * It is compliant with all of the following:
   6  *
   7  * RFC  821 - Simple Mail Transfer Protocol
   8  * RFC  876 - Survey of SMTP Implementations
   9  * RFC 1047 - Duplicate messages and SMTP
  10  * RFC 1652 - 8 bit MIME
  11  * RFC 1869 - Extended Simple Mail Transfer Protocol
  12  * RFC 1870 - SMTP Service Extension for Message Size Declaration
  13  * RFC 2033 - Local Mail Transfer Protocol
  14  * RFC 2197 - SMTP Service Extension for Command Pipelining
  15  * RFC 2476 - Message Submission
  16  * RFC 2487 - SMTP Service Extension for Secure SMTP over TLS
  17  * RFC 2554 - SMTP Service Extension for Authentication
  18  * RFC 2821 - Simple Mail Transfer Protocol
  19  * RFC 2822 - Internet Message Format
  20  * RFC 2920 - SMTP Service Extension for Command Pipelining
  21  *
  22  * The VRFY and EXPN commands have been removed from this implementation
  23  * because nobody uses these commands anymore, except for spammers.
  24  *
  25  * Copyright (c) 1998-2009 by the citadel.org team
  26  *
  27  *  This program is free software; you can redistribute it and/or modify
  28  *  it under the terms of the GNU General Public License as published by
  29  *  the Free Software Foundation; either version 3 of the License, or
  30  *  (at your option) any later version.
  31  *
  32  *  This program is distributed in the hope that it will be useful,
  33  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  34  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  35  *  GNU General Public License for more details.
  36  *
  37  *  You should have received a copy of the GNU General Public License
  38  *  along with this program; if not, write to the Free Software
  39  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  40  */
  41
  42 #include "sysdep.h"
  43 #include <stdlib.h>
  44 #include <unistd.h>
  45 #include <stdio.h>
  46 #include <fcntl.h>
  47 #include <signal.h>
  48 #include <pwd.h>
  49 #include <errno.h>
  50 #include <sys/types.h>
  51 #include <syslog.h>
  52
  53 #if TIME_WITH_SYS_TIME
  54 # include <sys/time.h>
  55 # include <time.h>
  56 #else
  57 # if HAVE_SYS_TIME_H
  58 #  include <sys/time.h>
  59 # else
  60 #  include <time.h>
  61 # endif
  62 #endif
  63
  64 #include <sys/wait.h>
  65 #include <ctype.h>
  66 #include <string.h>
  67 #include <limits.h>
  68 #include <sys/socket.h>
  69 #include <netinet/in.h>
  70 #include <arpa/inet.h>
  71 #include <libcitadel.h>
  72 #include "citadel.h"
  73 #include "server.h"
  74 #include "citserver.h"
  75 #include "support.h"
  76 #include "config.h"
  77 #include "control.h"
  78 #include "user_ops.h"
  79 #include "policy.h"
  80 #include "database.h"
  81 #include "msgbase.h"
  82 #include "internet_addressing.h"
  83 #include "genstamp.h"
  84 #include "domain.h"
  85 #include "clientsocket.h"
  86 #include "locate_host.h"
  87 #include "citadel_dirs.h"
  88
  89
  90
  91 #ifndef HAVE_SNPRINTF
  92 #include "snprintf.h"
  93 #endif
  94
  95
  96 #include "ctdl_module.h"
  97
  98
  99
 100 typedef struct _citsmtp {               /* Information about the current session */
 101         int command_state;
 102         char helo_node[SIZ];
 103         char from[SIZ];
 104         char recipients[SIZ];
 105         int number_of_recipients;
 106         int delivery_mode;
 107         int message_originated_locally;
 108         int is_lmtp;
 109         int is_unfiltered;
 110         int is_msa;
 111 }citsmtp;
 112
 113 enum {                          /* Command states for login authentication */
 114         smtp_command,
 115         smtp_user,
 116         smtp_password,
 117         smtp_plain
 118 };
 119
 120 #define SMTP            ((citsmtp *)CC->session_specific_data)
 121
 122
 123 int run_queue_now = 0;  /* Set to 1 to ignore SMTP send retry times */
 124
 125 citthread_mutex_t smtp_send_lock;
 126
 127
 128 /*****************************************************************************/
 129 /*                      SMTP SERVER (INBOUND) STUFF                          */
 130 /*****************************************************************************/
 131
 132
 133 /*
 134  * Here's where our SMTP session begins its happy day.
 135  */
 136 void smtp_greeting(int is_msa)
 137 {
 138         citsmtp *sSMTP;
 139         char message_to_spammer[1024];
 140
 141         strcpy(CC->cs_clientname, "SMTP session");
 142         CC->internal_pgm = 1;
 143         CC->cs_flags |= CS_STEALTH;
 144         CC->session_specific_data = malloc(sizeof(citsmtp));
 145         memset(SMTP, 0, sizeof(citsmtp));
 146         sSMTP = SMTP;
 147         sSMTP->is_msa = is_msa;
 148
 149         /* If this config option is set, reject connections from problem
 150          * addresses immediately instead of after they execute a RCPT
 151          */
 152         if ( (config.c_rbl_at_greeting) && (sSMTP->is_msa == 0) ) {
 153                 if (rbl_check(message_to_spammer)) {
 154                         if (CtdlThreadCheckStop())
 155                                 cprintf("421 %s\r\n", message_to_spammer);
 156                         else
 157                                 cprintf("550 %s\r\n", message_to_spammer);
 158                         CC->kill_me = 1;
 159                         /* no need to free_recipients(valid), it's not allocated yet */
 160                         return;
 161                 }
 162         }
 163
 164         /* Otherwise we're either clean or we check later. */
 165
 166         if (CC->nologin==1) {
 167                 cprintf("500 Too many users are already online (maximum is %d)\r\n",
 168                         config.c_maxsessions
 169                 );
 170                 CC->kill_me = 1;
 171                 /* no need to free_recipients(valid), it's not allocated yet */
 172                 return;
 173         }
 174
 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.
 177          */
 178         cprintf("220 %s ESMTP Citadel server ready.\r\n", config.c_fqdn);
 179 }
 180
 181
 182 /*
 183  * SMTPS is just like SMTP, except it goes crypto right away.
 184  */
 185 void smtps_greeting(void) {
 186         CtdlModuleStartCryptoMsgs(NULL, NULL, NULL);
 187 #ifdef HAVE_OPENSSL
 188         if (!CC->redirect_ssl) CC->kill_me = 1;         /* kill session if no crypto */
 189 #endif
 190         smtp_greeting(0);
 191 }
 192
 193
 194 /*
 195  * SMTP MSA port requires authentication.
 196  */
 197 void smtp_msa_greeting(void) {
 198         smtp_greeting(1);
 199 }
 200
 201
 202 /*
 203  * LMTP is like SMTP but with some extra bonus footage added.
 204  */
 205 void lmtp_greeting(void) {
 206         citsmtp *sSMTP;
 207
 208         smtp_greeting(0);
 209         sSMTP = SMTP;
 210         SMTP->is_lmtp = 1;
 211 }
 212
 213
 214 /*
 215  * Generic SMTP MTA greeting
 216  */
 217 void smtp_mta_greeting(void) {
 218         smtp_greeting(0);
 219 }
 220
 221
 222 /*
 223  * We also have an unfiltered LMTP socket that bypasses spam filters.
 224  */
 225 void lmtp_unfiltered_greeting(void) {
 226         citsmtp *sSMTP;
 227
 228         smtp_greeting(0);
 229         sSMTP = SMTP;
 230         sSMTP->is_lmtp = 1;
 231         sSMTP->is_unfiltered = 1;
 232 }
 233
 234
 235 /*
 236  * Login greeting common to all auth methods
 237  */
 238 void smtp_auth_greeting(void) {
 239                 cprintf("235 Hello, %s\r\n", CC->user.fullname);
 240                 CtdlLogPrintf(CTDL_NOTICE, "SMTP authenticated %s\n", CC->user.fullname);
 241                 CC->internal_pgm = 0;
 242                 CC->cs_flags &= ~CS_STEALTH;
 243 }
 244
 245
 246 /*
 247  * Implement HELO and EHLO commands.
 248  *
 249  * which_command:  0=HELO, 1=EHLO, 2=LHLO
 250  */
 251 void smtp_hello(char *argbuf, int which_command) {
 252         citsmtp *sSMTP = SMTP;
 253
 254         safestrncpy(sSMTP->helo_node, argbuf, sizeof sSMTP->helo_node);
 255
 256         if ( (which_command != 2) && (sSMTP->is_lmtp) ) {
 257                 cprintf("500 Only LHLO is allowed when running LMTP\r\n");
 258                 return;
 259         }
 260
 261         if ( (which_command == 2) && (sSMTP->is_lmtp == 0) ) {
 262                 cprintf("500 LHLO is only allowed when running LMTP\r\n");
 263                 return;
 264         }
 265
 266         if (which_command == 0) {
 267                 cprintf("250 Hello %s (%s [%s])\r\n",
 268                         sSMTP->helo_node,
 269                         CC->cs_host,
 270                         CC->cs_addr
 271                 );
 272         }
 273         else {
 274                 if (which_command == 1) {
 275                         cprintf("250-Hello %s (%s [%s])\r\n",
 276                                 sSMTP->helo_node,
 277                                 CC->cs_host,
 278                                 CC->cs_addr
 279                         );
 280                 }
 281                 else {
 282                         cprintf("250-Greetings and joyous salutations.\r\n");
 283                 }
 284                 cprintf("250-HELP\r\n");
 285                 cprintf("250-SIZE %ld\r\n", config.c_maxmsglen);
 286
 287 #ifdef HAVE_OPENSSL
 288                 /*
 289                  * Offer TLS, but only if TLS is not already active.
 290                  * Furthermore, only offer TLS when running on
 291                  * the SMTP-MSA port, not on the SMTP-MTA port, due to
 292                  * questionable reliability of TLS in certain sending MTA's.
 293                  */
 294                 if ( (!CC->redirect_ssl) && (sSMTP->is_msa) ) {
 295                         cprintf("250-STARTTLS\r\n");
 296                 }
 297 #endif  /* HAVE_OPENSSL */
 298
 299                 cprintf("250-AUTH LOGIN PLAIN\r\n"
 300                         "250-AUTH=LOGIN PLAIN\r\n"
 301                         "250 8BITMIME\r\n"
 302                 );
 303         }
 304 }
 305
 306
 307
 308 /*
 309  * Implement HELP command.
 310  */
 311 void smtp_help(void) {
 312         cprintf("214 RTFM http://www.ietf.org/rfc/rfc2821.txt\r\n");
 313 }
 314
 315
 316 /*
 317  *
 318  */
 319 void smtp_get_user(char *argbuf) {
 320         char buf[SIZ];
 321         char username[SIZ];
 322         citsmtp *sSMTP = SMTP;
 323
 324         CtdlDecodeBase64(username, argbuf, SIZ);
 325         /* CtdlLogPrintf(CTDL_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;
 330         }
 331         else {
 332                 cprintf("500 No such user.\r\n");
 333                 sSMTP->command_state = smtp_command;
 334         }
 335 }
 336
 337
 338 /*
 339  *
 340  */
 341 void smtp_get_pass(char *argbuf) {
 342         char password[SIZ];
 343
 344         memset(password, 0, sizeof(password));
 345         CtdlDecodeBase64(password, argbuf, SIZ);
 346         /* CtdlLogPrintf(CTDL_DEBUG, "Trying <%s>\n", password); */
 347         if (CtdlTryPassword(password) == pass_ok) {
 348                 smtp_auth_greeting();
 349         }
 350         else {
 351                 cprintf("535 Authentication failed.\r\n");
 352         }
 353         SMTP->command_state = smtp_command;
 354 }
 355
 356
 357 /*
 358  * Back end for PLAIN auth method (either inline or multistate)
 359  */
 360 void smtp_try_plain(char *encoded_authstring) {
 361         char decoded_authstring[1024];
 362         char ident[256];
 363         char user[256];
 364         char pass[256];
 365         int result;
 366
 367         CtdlDecodeBase64(decoded_authstring, encoded_authstring, strlen(encoded_authstring) );
 368         safestrncpy(ident, decoded_authstring, sizeof ident);
 369         safestrncpy(user, &decoded_authstring[strlen(ident) + 1], sizeof user);
 370         safestrncpy(pass, &decoded_authstring[strlen(ident) + strlen(user) + 2], sizeof pass);
 371
 372         SMTP->command_state = smtp_command;
 373
 374         if (!IsEmptyStr(ident)) {
 375                 result = CtdlLoginExistingUser(user, ident);
 376         }
 377         else {
 378                 result = CtdlLoginExistingUser(NULL, user);
 379         }
 380
 381         if (result == login_ok) {
 382                 if (CtdlTryPassword(pass) == pass_ok) {
 383                         smtp_auth_greeting();
 384                         return;
 385                 }
 386         }
 387         cprintf("504 Authentication failed.\r\n");
 388 }
 389
 390
 391 /*
 392  * Attempt to perform authenticated SMTP
 393  */
 394 void smtp_auth(char *argbuf) {
 395         char username_prompt[64];
 396         char method[64];
 397         char encoded_authstring[1024];
 398
 399         if (CC->logged_in) {
 400                 cprintf("504 Already logged in.\r\n");
 401                 return;
 402         }
 403
 404         extract_token(method, argbuf, 0, ' ', sizeof method);
 405
 406         if (!strncasecmp(method, "login", 5) ) {
 407                 if (strlen(argbuf) >= 7) {
 408                         smtp_get_user(&argbuf[6]);
 409                 }
 410                 else {
 411                         CtdlEncodeBase64(username_prompt, "Username:", 9, 0);
 412                         cprintf("334 %s\r\n", username_prompt);
 413                         SMTP->command_state = smtp_user;
 414                 }
 415                 return;
 416         }
 417
 418         if (!strncasecmp(method, "plain", 5) ) {
 419                 if (num_tokens(argbuf, ' ') < 2) {
 420                         cprintf("334 \r\n");
 421                         SMTP->command_state = smtp_plain;
 422                         return;
 423                 }
 424
 425                 extract_token(encoded_authstring, argbuf, 1, ' ', sizeof encoded_authstring);
 426
 427                 smtp_try_plain(encoded_authstring);
 428                 return;
 429         }
 430
 431         if (strncasecmp(method, "login", 5) ) {
 432                 cprintf("504 Unknown authentication method.\r\n");
 433                 return;
 434         }
 435
 436 }
 437
 438
 439 /*
 440  * Implements the RSET (reset state) command.
 441  * Currently this just zeroes out the state buffer.  If pointers to data
 442  * allocated with malloc() are ever placed in the state buffer, we have to
 443  * be sure to free() them first!
 444  *
 445  * Set do_response to nonzero to output the SMTP RSET response code.
 446  */
 447 void smtp_rset(int do_response) {
 448         int is_lmtp;
 449         int is_unfiltered;
 450         citsmtp *sSMTP = SMTP;
 451
 452         /*
 453          * Our entire SMTP state is discarded when a RSET command is issued,
 454          * but we need to preserve this one little piece of information, so
 455          * we save it for later.
 456          */
 457         is_lmtp = sSMTP->is_lmtp;
 458         is_unfiltered = sSMTP->is_unfiltered;
 459
 460         memset(sSMTP, 0, sizeof(citsmtp));
 461
 462         /*
 463          * It is somewhat ambiguous whether we want to log out when a RSET
 464          * command is issued.  Here's the code to do it.  It is commented out
 465          * because some clients (such as Pine) issue RSET commands before
 466          * each message, but still expect to be logged in.
 467          *
 468          * if (CC->logged_in) {
 469          *      logout(CC);
 470          * }
 471          */
 472
 473         /*
 474          * Reinstate this little piece of information we saved (see above).
 475          */
 476         sSMTP->is_lmtp = is_lmtp;
 477         sSMTP->is_unfiltered = is_unfiltered;
 478
 479         if (do_response) {
 480                 cprintf("250 Zap!\r\n");
 481         }
 482 }
 483
 484 /*
 485  * Clear out the portions of the state buffer that need to be cleared out
 486  * after the DATA command finishes.
 487  */
 488 void smtp_data_clear(void) {
 489         citsmtp *sSMTP = SMTP;
 490
 491         strcpy(sSMTP->from, "");
 492         strcpy(sSMTP->recipients, "");
 493         sSMTP->number_of_recipients = 0;
 494         sSMTP->delivery_mode = 0;
 495         sSMTP->message_originated_locally = 0;
 496 }
 497
 498 const char *smtp_get_Recipients(void)
 499 {
 500         citsmtp *sSMTP = SMTP;
 501
 502         if (sSMTP == NULL)
 503                 return NULL;
 504         else return sSMTP->from;
 505 }
 506
 507 /*
 508  * Implements the "MAIL FROM:" command
 509  */
 510 void smtp_mail(char *argbuf) {
 511         char user[SIZ];
 512         char node[SIZ];
 513         char name[SIZ];
 514         citsmtp *sSMTP = SMTP;
 515
 516         if (!IsEmptyStr(sSMTP->from)) {
 517                 cprintf("503 Only one sender permitted\r\n");
 518                 return;
 519         }
 520
 521         if (strncasecmp(argbuf, "From:", 5)) {
 522                 cprintf("501 Syntax error\r\n");
 523                 return;
 524         }
 525
 526         strcpy(sSMTP->from, &argbuf[5]);
 527         striplt(sSMTP->from);
 528         if (haschar(sSMTP->from, '<') > 0) {
 529                 stripallbut(sSMTP->from, '<', '>');
 530         }
 531
 532         /* We used to reject empty sender names, until it was brought to our
 533          * attention that RFC1123 5.2.9 requires that this be allowed.  So now
 534          * we allow it, but replace the empty string with a fake
 535          * address so we don't have to contend with the empty string causing
 536          * other code to fail when it's expecting something there.
 537          */
 538         if (IsEmptyStr(sSMTP->from)) {
 539                 strcpy(sSMTP->from, "someone@example.com");
 540         }
 541
 542         /* If this SMTP connection is from a logged-in user, force the 'from'
 543          * to be the user's Internet e-mail address as Citadel knows it.
 544          */
 545         if (CC->logged_in) {
 546                 safestrncpy(sSMTP->from, CC->cs_inet_email, sizeof sSMTP->from);
 547                 cprintf("250 Sender ok <%s>\r\n", sSMTP->from);
 548                 sSMTP->message_originated_locally = 1;
 549                 return;
 550         }
 551
 552         else if (sSMTP->is_lmtp) {
 553                 /* Bypass forgery checking for LMTP */
 554         }
 555
 556         /* Otherwise, make sure outsiders aren't trying to forge mail from
 557          * this system (unless, of course, c_allow_spoofing is enabled)
 558          */
 559         else if (config.c_allow_spoofing == 0) {
 560                 process_rfc822_addr(sSMTP->from, user, node, name);
 561                 if (CtdlHostAlias(node) != hostalias_nomatch) {
 562                         cprintf("550 You must log in to send mail from %s\r\n", node);
 563                         strcpy(sSMTP->from, "");
 564                         return;
 565                 }
 566         }
 567
 568         cprintf("250 Sender ok\r\n");
 569 }
 570
 571
 572
 573 /*
 574  * Implements the "RCPT To:" command
 575  */
 576 void smtp_rcpt(char *argbuf) {
 577         char recp[1024];
 578         char message_to_spammer[SIZ];
 579         struct recptypes *valid = NULL;
 580         citsmtp *sSMTP = SMTP;
 581
 582         if (IsEmptyStr(sSMTP->from)) {
 583                 cprintf("503 Need MAIL before RCPT\r\n");
 584                 return;
 585         }
 586
 587         if (strncasecmp(argbuf, "To:", 3)) {
 588                 cprintf("501 Syntax error\r\n");
 589                 return;
 590         }
 591
 592         if ( (sSMTP->is_msa) && (!CC->logged_in) ) {
 593                 cprintf("550 You must log in to send mail on this port.\r\n");
 594                 strcpy(sSMTP->from, "");
 595                 return;
 596         }
 597
 598         safestrncpy(recp, &argbuf[3], sizeof recp);
 599         striplt(recp);
 600         stripallbut(recp, '<', '>');
 601
 602         if ( (strlen(recp) + strlen(sSMTP->recipients) + 1 ) >= SIZ) {
 603                 cprintf("452 Too many recipients\r\n");
 604                 return;
 605         }
 606
 607         /* RBL check */
 608         if ( (!CC->logged_in)   /* Don't RBL authenticated users */
 609            && (!sSMTP->is_lmtp) ) {     /* Don't RBL LMTP clients */
 610                 if (config.c_rbl_at_greeting == 0) {    /* Don't RBL again if we already did it */
 611                         if (rbl_check(message_to_spammer)) {
 612                                 if (CtdlThreadCheckStop())
 613                                         cprintf("421 %s\r\n", message_to_spammer);
 614                                 else
 615                                         cprintf("550 %s\r\n", message_to_spammer);
 616                                 /* no need to free_recipients(valid), it's not allocated yet */
 617                                 return;
 618                         }
 619                 }
 620         }
 621
 622         valid = validate_recipients(recp,
 623                                     smtp_get_Recipients (),
 624                                     (sSMTP->is_lmtp)? POST_LMTP:
 625                                        (CC->logged_in)? POST_LOGGED_IN:
 626                                                         POST_EXTERNAL);
 627         if (valid->num_error != 0) {
 628                 cprintf("550 %s\r\n", valid->errormsg);
 629                 free_recipients(valid);
 630                 return;
 631         }
 632
 633         if (valid->num_internet > 0) {
 634                 if (CC->logged_in) {
 635                         if (CtdlCheckInternetMailPermission(&CC->user)==0) {
 636                                 cprintf("551 <%s> - you do not have permission to send Internet mail\r\n", recp);
 637                                 free_recipients(valid);
 638                                 return;
 639                         }
 640                 }
 641         }
 642
 643         if (valid->num_internet > 0) {
 644                 if ( (sSMTP->message_originated_locally == 0)
 645                    && (sSMTP->is_lmtp == 0) ) {
 646                         cprintf("551 <%s> - relaying denied\r\n", recp);
 647                         free_recipients(valid);
 648                         return;
 649                 }
 650         }
 651
 652         cprintf("250 RCPT ok <%s>\r\n", recp);
 653         if (!IsEmptyStr(sSMTP->recipients)) {
 654                 strcat(sSMTP->recipients, ",");
 655         }
 656         strcat(sSMTP->recipients, recp);
 657         sSMTP->number_of_recipients += 1;
 658         if (valid != NULL)  {
 659                 free_recipients(valid);
 660         }
 661 }
 662
 663
 664
 665
 666 /*
 667  * Implements the DATA command
 668  */
 669 void smtp_data(void) {
 670         StrBuf *body;
 671         char *defbody; //TODO: remove me
 672         struct CtdlMessage *msg = NULL;
 673         long msgnum = (-1L);
 674         char nowstamp[SIZ];
 675         struct recptypes *valid;
 676         int scan_errors;
 677         int i;
 678         char result[SIZ];
 679         citsmtp *sSMTP = SMTP;
 680
 681         if (IsEmptyStr(sSMTP->from)) {
 682                 cprintf("503 Need MAIL command first.\r\n");
 683                 return;
 684         }
 685
 686         if (sSMTP->number_of_recipients < 1) {
 687                 cprintf("503 Need RCPT command first.\r\n");
 688                 return;
 689         }
 690
 691         cprintf("354 Transmit message now - terminate with '.' by itself\r\n");
 692
 693         datestring(nowstamp, sizeof nowstamp, time(NULL), DATESTRING_RFC822);
 694         defbody = malloc(4096);
 695
 696         if (body != NULL) {
 697                 if (sSMTP->is_lmtp && (CC->cs_UDSclientUID != -1)) {
 698                         snprintf(defbody, 4096,
 699                                "Received: from %s (Citadel from userid %ld)\n"
 700                                "        by %s; %s\n",
 701                                sSMTP->helo_node,
 702                                (long int) CC->cs_UDSclientUID,
 703                                config.c_fqdn,
 704                                nowstamp);
 705                 }
 706                 else {
 707                         snprintf(defbody, 4096,
 708                                  "Received: from %s (%s [%s])\n"
 709                                  "      by %s; %s\n",
 710                                  sSMTP->helo_node,
 711                                  CC->cs_host,
 712                                  CC->cs_addr,
 713                                  config.c_fqdn,
 714                                  nowstamp);
 715                 }
 716         }
 717         body = CtdlReadMessageBodyBuf(HKEY("."), config.c_maxmsglen, defbody, 1, NULL);
 718         if (body == NULL) {
 719                 cprintf("550 Unable to save message: internal error.\r\n");
 720                 return;
 721         }
 722
 723         CtdlLogPrintf(CTDL_DEBUG, "Converting message...\n");
 724         msg = convert_internet_message_buf(&body);
 725
 726         /* If the user is locally authenticated, FORCE the From: header to
 727          * show up as the real sender.  Yes, this violates the RFC standard,
 728          * but IT MAKES SENSE.  If you prefer strict RFC adherence over
 729          * common sense, you can disable this in the configuration.
 730          *
 731          * We also set the "message room name" ('O' field) to MAILROOM
 732          * (which is Mail> on most systems) to prevent it from getting set
 733          * to something ugly like "0000058008.Sent Items>" when the message
 734          * is read with a Citadel client.
 735          */
 736         if ( (CC->logged_in) && (config.c_rfc822_strict_from == 0) ) {
 737                 if (msg->cm_fields['A'] != NULL) free(msg->cm_fields['A']);
 738                 if (msg->cm_fields['N'] != NULL) free(msg->cm_fields['N']);
 739                 if (msg->cm_fields['H'] != NULL) free(msg->cm_fields['H']);
 740                 if (msg->cm_fields['F'] != NULL) free(msg->cm_fields['F']);
 741                 if (msg->cm_fields['O'] != NULL) free(msg->cm_fields['O']);
 742                 msg->cm_fields['A'] = strdup(CC->user.fullname);
 743                 msg->cm_fields['N'] = strdup(config.c_nodename);
 744                 msg->cm_fields['H'] = strdup(config.c_humannode);
 745                 msg->cm_fields['F'] = strdup(CC->cs_inet_email);
 746                 msg->cm_fields['O'] = strdup(MAILROOM);
 747         }
 748
 749         /* Set the "envelope from" address */
 750         if (msg->cm_fields['P'] != NULL) {
 751                 free(msg->cm_fields['P']);
 752         }
 753         msg->cm_fields['P'] = strdup(sSMTP->from);
 754
 755         /* Set the "envelope to" address */
 756         if (msg->cm_fields['V'] != NULL) {
 757                 free(msg->cm_fields['V']);
 758         }
 759         msg->cm_fields['V'] = strdup(sSMTP->recipients);
 760
 761         /* Submit the message into the Citadel system. */
 762         valid = validate_recipients(sSMTP->recipients,
 763                                     smtp_get_Recipients (),
 764                                     (sSMTP->is_lmtp)? POST_LMTP:
 765                                        (CC->logged_in)? POST_LOGGED_IN:
 766                                                         POST_EXTERNAL);
 767
 768         /* If there are modules that want to scan this message before final
 769          * submission (such as virus checkers or spam filters), call them now
 770          * and give them an opportunity to reject the message.
 771          */
 772         if (sSMTP->is_unfiltered) {
 773                 scan_errors = 0;
 774         }
 775         else {
 776                 scan_errors = PerformMessageHooks(msg, EVT_SMTPSCAN);
 777         }
 778
 779         if (scan_errors > 0) {  /* We don't want this message! */
 780
 781                 if (msg->cm_fields['0'] == NULL) {
 782                         msg->cm_fields['0'] = strdup("Message rejected by filter");
 783                 }
 784
 785                 sprintf(result, "550 %s\r\n", msg->cm_fields['0']);
 786         }
 787
 788         else {                  /* Ok, we'll accept this message. */
 789                 msgnum = CtdlSubmitMsg(msg, valid, "", 0);
 790                 if (msgnum > 0L) {
 791                         sprintf(result, "250 Message accepted.\r\n");
 792                 }
 793                 else {
 794                         sprintf(result, "550 Internal delivery error\r\n");
 795                 }
 796         }
 797
 798         /* For SMTP and ESTMP, just print the result message.  For LMTP, we
 799          * have to print one result message for each recipient.  Since there
 800          * is nothing in Citadel which would cause different recipients to
 801          * have different results, we can get away with just spitting out the
 802          * same message once for each recipient.
 803          */
 804         if (sSMTP->is_lmtp) {
 805                 for (i=0; i<sSMTP->number_of_recipients; ++i) {
 806                         cprintf("%s", result);
 807                 }
 808         }
 809         else {
 810                 cprintf("%s", result);
 811         }
 812
 813         /* Write something to the syslog (which may or may not be where the
 814          * rest of the Citadel logs are going; some sysadmins want LOG_MAIL).
 815          */
 816         if (enable_syslog) {
 817                 syslog((LOG_MAIL | LOG_INFO),
 818                         "%ld: from=<%s>, nrcpts=%d, relay=%s [%s], stat=%s",
 819                         msgnum,
 820                         sSMTP->from,
 821                         sSMTP->number_of_recipients,
 822                         CC->cs_host,
 823                         CC->cs_addr,
 824                         result
 825                 );
 826         }
 827
 828         /* Clean up */
 829         CtdlFreeMessage(msg);
 830         free_recipients(valid);
 831         smtp_data_clear();      /* clear out the buffers now */
 832 }
 833
 834
 835 /*
 836  * implements the STARTTLS command (Citadel API version)
 837  */
 838 void smtp_starttls(void)
 839 {
 840         char ok_response[SIZ];
 841         char nosup_response[SIZ];
 842         char error_response[SIZ];
 843
 844         sprintf(ok_response,
 845                 "220 Begin TLS negotiation now\r\n");
 846         sprintf(nosup_response,
 847                 "554 TLS not supported here\r\n");
 848         sprintf(error_response,
 849                 "554 Internal error\r\n");
 850         CtdlModuleStartCryptoMsgs(ok_response, nosup_response, error_response);
 851         smtp_rset(0);
 852 }
 853
 854
 855
 856 /*
 857  * Main command loop for SMTP sessions.
 858  */
 859 void smtp_command_loop(void) {
 860         char cmdbuf[SIZ];
 861         citsmtp *sSMTP = SMTP;
 862
 863         if (sSMTP == NULL) {
 864                 CtdlLogPrintf(CTDL_EMERG, "Session SMTP data is null.  WTF?  We will crash now.\n");
 865         }
 866
 867         time(&CC->lastcmd);
 868         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
 869         if (client_getln(cmdbuf, sizeof cmdbuf) < 1) {
 870                 CtdlLogPrintf(CTDL_CRIT, "Client disconnected: ending session.\n");
 871                 CC->kill_me = 1;
 872                 return;
 873         }
 874         CtdlLogPrintf(CTDL_INFO, "SMTP server: %s\n", cmdbuf);
 875         while (strlen(cmdbuf) < 5) strcat(cmdbuf, " ");
 876
 877         if (sSMTP->command_state == smtp_user) {
 878                 smtp_get_user(cmdbuf);
 879         }
 880
 881         else if (sSMTP->command_state == smtp_password) {
 882                 smtp_get_pass(cmdbuf);
 883         }
 884
 885         else if (sSMTP->command_state == smtp_plain) {
 886                 smtp_try_plain(cmdbuf);
 887         }
 888
 889         else if (!strncasecmp(cmdbuf, "AUTH", 4)) {
 890                 smtp_auth(&cmdbuf[5]);
 891         }
 892
 893         else if (!strncasecmp(cmdbuf, "DATA", 4)) {
 894                 smtp_data();
 895         }
 896
 897         else if (!strncasecmp(cmdbuf, "HELO", 4)) {
 898                 smtp_hello(&cmdbuf[5], 0);
 899         }
 900
 901         else if (!strncasecmp(cmdbuf, "EHLO", 4)) {
 902                 smtp_hello(&cmdbuf[5], 1);
 903         }
 904
 905         else if (!strncasecmp(cmdbuf, "LHLO", 4)) {
 906                 smtp_hello(&cmdbuf[5], 2);
 907         }
 908
 909         else if (!strncasecmp(cmdbuf, "HELP", 4)) {
 910                 smtp_help();
 911         }
 912
 913         else if (!strncasecmp(cmdbuf, "MAIL", 4)) {
 914                 smtp_mail(&cmdbuf[5]);
 915         }
 916
 917         else if (!strncasecmp(cmdbuf, "NOOP", 4)) {
 918                 cprintf("250 NOOP\r\n");
 919         }
 920
 921         else if (!strncasecmp(cmdbuf, "QUIT", 4)) {
 922                 cprintf("221 Goodbye...\r\n");
 923                 CC->kill_me = 1;
 924                 return;
 925         }
 926
 927         else if (!strncasecmp(cmdbuf, "RCPT", 4)) {
 928                 smtp_rcpt(&cmdbuf[5]);
 929         }
 930
 931         else if (!strncasecmp(cmdbuf, "RSET", 4)) {
 932                 smtp_rset(1);
 933         }
 934 #ifdef HAVE_OPENSSL
 935         else if (!strcasecmp(cmdbuf, "STARTTLS")) {
 936                 smtp_starttls();
 937         }
 938 #endif
 939         else {
 940                 cprintf("502 I'm afraid I can't do that.\r\n");
 941         }
 942
 943
 944 }
 945
 946
 947
 948
 949 /*****************************************************************************/
 950 /*               SMTP CLIENT (OUTBOUND PROCESSING) STUFF                     */
 951 /*****************************************************************************/
 952
 953
 954
 955 /*
 956  * smtp_try()
 957  *
 958  * Called by smtp_do_procmsg() to attempt delivery to one SMTP host
 959  *
 960  */
 961 void smtp_try(const char *key, const char *addr, int *status,
 962               char *dsn, size_t n, long msgnum, char *envelope_from)
 963 {
 964         int sock = (-1);
 965         char mxhosts[1024];
 966         int num_mxhosts;
 967         int mx;
 968         int i;
 969         char user[1024], node[1024], name[1024];
 970         char buf[1024];
 971         char mailfrom[1024];
 972         char mx_user[256];
 973         char mx_pass[256];
 974         char mx_host[256];
 975         char mx_port[256];
 976         int lp, rp;
 977         char *msgtext;
 978         char *ptr;
 979         size_t msg_size;
 980         int scan_done;
 981
 982
 983         /* Parse out the host portion of the recipient address */
 984         process_rfc822_addr(addr, user, node, name);
 985
 986         CtdlLogPrintf(CTDL_DEBUG, "SMTP client: Attempting delivery to <%s> @ <%s> (%s)\n",
 987                 user, node, name);
 988
 989         /* Load the message out of the database */
 990         CC->redirect_buffer = malloc(SIZ);
 991         CC->redirect_len = 0;
 992         CC->redirect_alloc = SIZ;
 993         CtdlOutputMsg(msgnum, MT_RFC822, HEADERS_ALL, 0, 1, NULL, ESC_DOT);
 994         msgtext = CC->redirect_buffer;
 995         msg_size = CC->redirect_len;
 996         CC->redirect_buffer = NULL;
 997         CC->redirect_len = 0;
 998         CC->redirect_alloc = 0;
 999
1000         /* If no envelope_from is supplied, extract one from the message */
1001         if ( (envelope_from == NULL) || (IsEmptyStr(envelope_from)) ) {
1002                 strcpy(mailfrom, "");
1003                 scan_done = 0;
1004                 ptr = msgtext;
1005                 do {
1006                         if (ptr = memreadline(ptr, buf, sizeof buf), *ptr == 0) {
1007                                 scan_done = 1;
1008                         }
1009                         if (!strncasecmp(buf, "From:", 5)) {
1010                                 safestrncpy(mailfrom, &buf[5], sizeof mailfrom);
1011                                 striplt(mailfrom);
1012                                 for (i=0; mailfrom[i]; ++i) {
1013                                         if (!isprint(mailfrom[i])) {
1014                                                 strcpy(&mailfrom[i], &mailfrom[i+1]);
1015                                                 i=0;
1016                                         }
1017                                 }
1018
1019                                 /* Strip out parenthesized names */
1020                                 lp = (-1);
1021                                 rp = (-1);
1022                                 for (i=0; mailfrom[i]; ++i) {
1023                                         if (mailfrom[i] == '(') lp = i;
1024                                         if (mailfrom[i] == ')') rp = i;
1025                                 }
1026                                 if ((lp>0)&&(rp>lp)) {
1027                                         strcpy(&mailfrom[lp-1], &mailfrom[rp+1]);
1028                                 }
1029
1030                                 /* Prefer brokketized names */
1031                                 lp = (-1);
1032                                 rp = (-1);
1033                                 for (i=0; mailfrom[i]; ++i) {
1034                                         if (mailfrom[i] == '<') lp = i;
1035                                         if (mailfrom[i] == '>') rp = i;
1036                                 }
1037                                 if ( (lp>=0) && (rp>lp) ) {
1038                                         mailfrom[rp] = 0;
1039                                         strcpy(mailfrom, &mailfrom[lp]);
1040                                 }
1041
1042                                 scan_done = 1;
1043                         }
1044                 } while (scan_done == 0);
1045                 if (IsEmptyStr(mailfrom)) strcpy(mailfrom, "someone@somewhere.org");
1046                 stripallbut(mailfrom, '<', '>');
1047                 envelope_from = mailfrom;
1048         }
1049
1050         /* Figure out what mail exchanger host we have to connect to */
1051         num_mxhosts = getmx(mxhosts, node);
1052         CtdlLogPrintf(CTDL_DEBUG, "Number of MX hosts for <%s> is %d [%s]\n", node, num_mxhosts, mxhosts);
1053         if (num_mxhosts < 1) {
1054                 *status = 5;
1055                 snprintf(dsn, SIZ, "No MX hosts found for <%s>", node);
1056                 return;
1057         }
1058
1059         sock = (-1);
1060         for (mx=0; (mx<num_mxhosts && sock < 0); ++mx) {
1061                 char *endpart;
1062                 extract_token(buf, mxhosts, mx, '|', sizeof buf);
1063                 strcpy(mx_user, "");
1064                 strcpy(mx_pass, "");
1065                 if (num_tokens(buf, '@') > 1) {
1066                         strcpy (mx_user, buf);
1067                         endpart = strrchr(mx_user, '@');
1068                         *endpart = '\0';
1069                         strcpy (mx_host, endpart + 1);
1070                         endpart = strrchr(mx_user, ':');
1071                         if (endpart != NULL) {
1072                                 strcpy(mx_pass, endpart+1);
1073                                 *endpart = '\0';
1074                         }
1075                 }
1076                 else
1077                         strcpy (mx_host, buf);
1078                 endpart = strrchr(mx_host, ':');
1079                 if (endpart != 0){
1080                         *endpart = '\0';
1081                         strcpy(mx_port, endpart + 1);
1082                 }
1083                 else {
1084                         strcpy(mx_port, "25");
1085                 }
1086                 CtdlLogPrintf(CTDL_DEBUG, "SMTP client: connecting to %s : %s ...\n", mx_host, mx_port);
1087                 sock = sock_connect(mx_host, mx_port, "tcp");
1088                 snprintf(dsn, SIZ, "Could not connect: %s", strerror(errno));
1089                 if (sock >= 0) CtdlLogPrintf(CTDL_DEBUG, "SMTP client: connected!\n");
1090                 if (sock < 0) {
1091                         if (errno > 0) {
1092                                 snprintf(dsn, SIZ, "%s", strerror(errno));
1093                         }
1094                         else {
1095                                 snprintf(dsn, SIZ, "Unable to connect to %s : %s\n", mx_host, mx_port);
1096                         }
1097                 }
1098         }
1099
1100         if (sock < 0) {
1101                 *status = 4;    /* dsn is already filled in */
1102                 return;
1103         }
1104
1105         /* Process the SMTP greeting from the server */
1106         if (ml_sock_gets(&sock, buf) < 0) {
1107                 *status = 4;
1108                 strcpy(dsn, "Connection broken during SMTP conversation");
1109                 goto bail;
1110         }
1111         CtdlLogPrintf(CTDL_DEBUG, "<%s\n", buf);
1112         if (buf[0] != '2') {
1113                 if (buf[0] == '4') {
1114                         *status = 4;
1115                         safestrncpy(dsn, &buf[4], 1023);
1116                         goto bail;
1117                 }
1118                 else {
1119                         *status = 5;
1120                         safestrncpy(dsn, &buf[4], 1023);
1121                         goto bail;
1122                 }
1123         }
1124
1125         /* At this point we know we are talking to a real SMTP server */
1126
1127         /* Do a EHLO command.  If it fails, try the HELO command. */
1128         snprintf(buf, sizeof buf, "EHLO %s\r\n", config.c_fqdn);
1129         CtdlLogPrintf(CTDL_DEBUG, ">%s", buf);
1130         sock_write(sock, buf, strlen(buf));
1131         if (ml_sock_gets(&sock, buf) < 0) {
1132                 *status = 4;
1133                 strcpy(dsn, "Connection broken during SMTP HELO");
1134                 goto bail;
1135         }
1136         CtdlLogPrintf(CTDL_DEBUG, "<%s\n", buf);
1137         if (buf[0] != '2') {
1138                 snprintf(buf, sizeof buf, "HELO %s\r\n", config.c_fqdn);
1139                 CtdlLogPrintf(CTDL_DEBUG, ">%s", buf);
1140                 sock_write(sock, buf, strlen(buf));
1141                 if (ml_sock_gets(&sock, buf) < 0) {
1142                         *status = 4;
1143                         strcpy(dsn, "Connection broken during SMTP HELO");
1144                         goto bail;
1145                 }
1146         }
1147         if (buf[0] != '2') {
1148                 if (buf[0] == '4') {
1149                         *status = 4;
1150                         safestrncpy(dsn, &buf[4], 1023);
1151                         goto bail;
1152                 }
1153                 else {
1154                         *status = 5;
1155                         safestrncpy(dsn, &buf[4], 1023);
1156                         goto bail;
1157                 }
1158         }
1159
1160         /* Do an AUTH command if necessary */
1161         if (!IsEmptyStr(mx_user)) {
1162                 char encoded[1024];
1163                 sprintf(buf, "%s%c%s%c%s", mx_user, '\0', mx_user, '\0', mx_pass);
1164                 CtdlEncodeBase64(encoded, buf, strlen(mx_user) + strlen(mx_user) + strlen(mx_pass) + 2, 0);
1165                 snprintf(buf, sizeof buf, "AUTH PLAIN %s\r\n", encoded);
1166                 CtdlLogPrintf(CTDL_DEBUG, ">%s", buf);
1167                 sock_write(sock, buf, strlen(buf));
1168                 if (ml_sock_gets(&sock, buf) < 0) {
1169                         *status = 4;
1170                         strcpy(dsn, "Connection broken during SMTP AUTH");
1171                         goto bail;
1172                 }
1173                 CtdlLogPrintf(CTDL_DEBUG, "<%s\n", buf);
1174                 if (buf[0] != '2') {
1175                         if (buf[0] == '4') {
1176                                 *status = 4;
1177                                 safestrncpy(dsn, &buf[4], 1023);
1178                                 goto bail;
1179                         }
1180                         else {
1181                                 *status = 5;
1182                                 safestrncpy(dsn, &buf[4], 1023);
1183                                 goto bail;
1184                         }
1185                 }
1186         }
1187
1188         /* previous command succeeded, now try the MAIL FROM: command */
1189         snprintf(buf, sizeof buf, "MAIL FROM:<%s>\r\n", envelope_from);
1190         CtdlLogPrintf(CTDL_DEBUG, ">%s", buf);
1191         sock_write(sock, buf, strlen(buf));
1192         if (ml_sock_gets(&sock, buf) < 0) {
1193                 *status = 4;
1194                 strcpy(dsn, "Connection broken during SMTP MAIL");
1195                 goto bail;
1196         }
1197         CtdlLogPrintf(CTDL_DEBUG, "<%s\n", buf);
1198         if (buf[0] != '2') {
1199                 if (buf[0] == '4') {
1200                         *status = 4;
1201                         safestrncpy(dsn, &buf[4], 1023);
1202                         goto bail;
1203                 }
1204                 else {
1205                         *status = 5;
1206                         safestrncpy(dsn, &buf[4], 1023);
1207                         goto bail;
1208                 }
1209         }
1210
1211         /* MAIL succeeded, now try the RCPT To: command */
1212         snprintf(buf, sizeof buf, "RCPT TO:<%s@%s>\r\n", user, node);
1213         CtdlLogPrintf(CTDL_DEBUG, ">%s", buf);
1214         sock_write(sock, buf, strlen(buf));
1215         if (ml_sock_gets(&sock, buf) < 0) {
1216                 *status = 4;
1217                 strcpy(dsn, "Connection broken during SMTP RCPT");
1218                 goto bail;
1219         }
1220         CtdlLogPrintf(CTDL_DEBUG, "<%s\n", buf);
1221         if (buf[0] != '2') {
1222                 if (buf[0] == '4') {
1223                         *status = 4;
1224                         safestrncpy(dsn, &buf[4], 1023);
1225                         goto bail;
1226                 }
1227                 else {
1228                         *status = 5;
1229                         safestrncpy(dsn, &buf[4], 1023);
1230                         goto bail;
1231                 }
1232         }
1233
1234         /* RCPT succeeded, now try the DATA command */
1235         CtdlLogPrintf(CTDL_DEBUG, ">DATA\n");
1236         sock_write(sock, "DATA\r\n", 6);
1237         if (ml_sock_gets(&sock, buf) < 0) {
1238                 *status = 4;
1239                 strcpy(dsn, "Connection broken during SMTP DATA");
1240                 goto bail;
1241         }
1242         CtdlLogPrintf(CTDL_DEBUG, "<%s\n", buf);
1243         if (buf[0] != '3') {
1244                 if (buf[0] == '4') {
1245                         *status = 3;
1246                         safestrncpy(dsn, &buf[4], 1023);
1247                         goto bail;
1248                 }
1249                 else {
1250                         *status = 5;
1251                         safestrncpy(dsn, &buf[4], 1023);
1252                         goto bail;
1253                 }
1254         }
1255
1256         /* If we reach this point, the server is expecting data.*/
1257         sock_write(sock, msgtext, msg_size);
1258         if (msgtext[msg_size-1] != 10) {
1259                 CtdlLogPrintf(CTDL_WARNING, "Possible problem: message did not "
1260                         "correctly terminate. (expecting 0x10, got 0x%02x)\n",
1261                                 buf[msg_size-1]);
1262                 sock_write(sock, "\r\n", 2);
1263         }
1264
1265         sock_write(sock, ".\r\n", 3);
1266         if (ml_sock_gets(&sock, buf) < 0) {
1267                 *status = 4;
1268                 strcpy(dsn, "Connection broken during SMTP message transmit");
1269                 goto bail;
1270         }
1271         CtdlLogPrintf(CTDL_DEBUG, "%s\n", buf);
1272         if (buf[0] != '2') {
1273                 if (buf[0] == '4') {
1274                         *status = 4;
1275                         safestrncpy(dsn, &buf[4], 1023);
1276                         goto bail;
1277                 }
1278                 else {
1279                         *status = 5;
1280                         safestrncpy(dsn, &buf[4], 1023);
1281                         goto bail;
1282                 }
1283         }
1284
1285         /* We did it! */
1286         safestrncpy(dsn, &buf[4], 1023);
1287         *status = 2;
1288
1289         CtdlLogPrintf(CTDL_DEBUG, ">QUIT\n");
1290         sock_write(sock, "QUIT\r\n", 6);
1291         ml_sock_gets(&sock, buf);
1292         CtdlLogPrintf(CTDL_DEBUG, "<%s\n", buf);
1293         CtdlLogPrintf(CTDL_INFO, "SMTP client: delivery to <%s> @ <%s> (%s) succeeded\n",
1294                 user, node, name);
1295
1296 bail:   free(msgtext);
1297         sock_close(sock);
1298
1299         /* Write something to the syslog (which may or may not be where the
1300          * rest of the Citadel logs are going; some sysadmins want LOG_MAIL).
1301          */
1302         if (enable_syslog) {
1303                 syslog((LOG_MAIL | LOG_INFO),
1304                         "%ld: to=<%s>, relay=%s, stat=%s",
1305                         msgnum,
1306                         addr,
1307                         mx_host,
1308                         dsn
1309                 );
1310         }
1311
1312         return;
1313 }
1314
1315
1316
1317 /*
1318  * smtp_do_bounce() is caled by smtp_do_procmsg() to scan a set of delivery
1319  * instructions for "5" codes (permanent fatal errors) and produce/deliver
1320  * a "bounce" message (delivery status notification).
1321  */
1322 void smtp_do_bounce(char *instr) {
1323         int i;
1324         int lines;
1325         int status;
1326         char buf[1024];
1327         char key[1024];
1328         char addr[1024];
1329         char dsn[1024];
1330         char bounceto[1024];
1331         char boundary[64];
1332         int num_bounces = 0;
1333         int bounce_this = 0;
1334         long bounce_msgid = (-1);
1335         time_t submitted = 0L;
1336         struct CtdlMessage *bmsg = NULL;
1337         int give_up = 0;
1338         struct recptypes *valid;
1339         int successful_bounce = 0;
1340         static int seq = 0;
1341         char *omsgtext;
1342         size_t omsgsize;
1343         long omsgid = (-1);
1344
1345         CtdlLogPrintf(CTDL_DEBUG, "smtp_do_bounce() called\n");
1346         strcpy(bounceto, "");
1347         sprintf(boundary, "=_Citadel_Multipart_%s_%04x%04x", config.c_fqdn, getpid(), ++seq);
1348         lines = num_tokens(instr, '\n');
1349
1350         /* See if it's time to give up on delivery of this message */
1351         for (i=0; i<lines; ++i) {
1352                 extract_token(buf, instr, i, '\n', sizeof buf);
1353                 extract_token(key, buf, 0, '|', sizeof key);
1354                 extract_token(addr, buf, 1, '|', sizeof addr);
1355                 if (!strcasecmp(key, "submitted")) {
1356                         submitted = atol(addr);
1357                 }
1358         }
1359
1360         if ( (time(NULL) - submitted) > SMTP_GIVE_UP ) {
1361                 give_up = 1;
1362         }
1363
1364         /* Start building our bounce message */
1365
1366         bmsg = (struct CtdlMessage *) malloc(sizeof(struct CtdlMessage));
1367         if (bmsg == NULL) return;
1368         memset(bmsg, 0, sizeof(struct CtdlMessage));
1369
1370         bmsg->cm_magic = CTDLMESSAGE_MAGIC;
1371         bmsg->cm_anon_type = MES_NORMAL;
1372         bmsg->cm_format_type = FMT_RFC822;
1373         bmsg->cm_fields['A'] = strdup("Citadel");
1374         bmsg->cm_fields['O'] = strdup(MAILROOM);
1375         bmsg->cm_fields['N'] = strdup(config.c_nodename);
1376         bmsg->cm_fields['U'] = strdup("Delivery Status Notification (Failure)");
1377         bmsg->cm_fields['M'] = malloc(1024);
1378
1379         strcpy(bmsg->cm_fields['M'], "Content-type: multipart/mixed; boundary=\"");
1380         strcat(bmsg->cm_fields['M'], boundary);
1381         strcat(bmsg->cm_fields['M'], "\"\r\n");
1382         strcat(bmsg->cm_fields['M'], "MIME-Version: 1.0\r\n");
1383         strcat(bmsg->cm_fields['M'], "X-Mailer: " CITADEL "\r\n");
1384         strcat(bmsg->cm_fields['M'], "\r\nThis is a multipart message in MIME format.\r\n\r\n");
1385         strcat(bmsg->cm_fields['M'], "--");
1386         strcat(bmsg->cm_fields['M'], boundary);
1387         strcat(bmsg->cm_fields['M'], "\r\n");
1388         strcat(bmsg->cm_fields['M'], "Content-type: text/plain\r\n\r\n");
1389
1390         if (give_up) strcat(bmsg->cm_fields['M'],
1391 "A message you sent could not be delivered to some or all of its recipients\n"
1392 "due to prolonged unavailability of its destination(s).\n"
1393 "Giving up on the following addresses:\n\n"
1394 );
1395
1396         else strcat(bmsg->cm_fields['M'],
1397 "A message you sent could not be delivered to some or all of its recipients.\n"
1398 "The following addresses were undeliverable:\n\n"
1399 );
1400
1401         /*
1402          * Now go through the instructions checking for stuff.
1403          */
1404         for (i=0; i<lines; ++i) {
1405                 extract_token(buf, instr, i, '\n', sizeof buf);
1406                 extract_token(key, buf, 0, '|', sizeof key);
1407                 extract_token(addr, buf, 1, '|', sizeof addr);
1408                 status = extract_int(buf, 2);
1409                 extract_token(dsn, buf, 3, '|', sizeof dsn);
1410                 bounce_this = 0;
1411
1412                 CtdlLogPrintf(CTDL_DEBUG, "key=<%s> addr=<%s> status=%d dsn=<%s>\n",
1413                         key, addr, status, dsn);
1414
1415                 if (!strcasecmp(key, "bounceto")) {
1416                         strcpy(bounceto, addr);
1417                 }
1418
1419                 if (!strcasecmp(key, "msgid")) {
1420                         omsgid = atol(addr);
1421                 }
1422
1423                 if (!strcasecmp(key, "remote")) {
1424                         if (status == 5) bounce_this = 1;
1425                         if (give_up) bounce_this = 1;
1426                 }
1427
1428                 if (bounce_this) {
1429                         ++num_bounces;
1430
1431                         if (bmsg->cm_fields['M'] == NULL) {
1432                                 CtdlLogPrintf(CTDL_ERR, "ERROR ... M field is null "
1433                                         "(%s:%d)\n", __FILE__, __LINE__);
1434                         }
1435
1436                         bmsg->cm_fields['M'] = realloc(bmsg->cm_fields['M'],
1437                                 strlen(bmsg->cm_fields['M']) + 1024 );
1438                         strcat(bmsg->cm_fields['M'], addr);
1439                         strcat(bmsg->cm_fields['M'], ": ");
1440                         strcat(bmsg->cm_fields['M'], dsn);
1441                         strcat(bmsg->cm_fields['M'], "\r\n");
1442
1443                         remove_token(instr, i, '\n');
1444                         --i;
1445                         --lines;
1446                 }
1447         }
1448
1449         /* Attach the original message */
1450         if (omsgid >= 0) {
1451                 strcat(bmsg->cm_fields['M'], "--");
1452                 strcat(bmsg->cm_fields['M'], boundary);
1453                 strcat(bmsg->cm_fields['M'], "\r\n");
1454                 strcat(bmsg->cm_fields['M'], "Content-type: message/rfc822\r\n");
1455                 strcat(bmsg->cm_fields['M'], "Content-Transfer-Encoding: 7bit\r\n");
1456                 strcat(bmsg->cm_fields['M'], "Content-Disposition: inline\r\n");
1457                 strcat(bmsg->cm_fields['M'], "\r\n");
1458
1459                 CC->redirect_buffer = malloc(SIZ);
1460                 CC->redirect_len = 0;
1461                 CC->redirect_alloc = SIZ;
1462                 CtdlOutputMsg(omsgid, MT_RFC822, HEADERS_ALL, 0, 1, NULL, 0);
1463                 omsgtext = CC->redirect_buffer;
1464                 omsgsize = CC->redirect_len;
1465                 CC->redirect_buffer = NULL;
1466                 CC->redirect_len = 0;
1467                 CC->redirect_alloc = 0;
1468                 bmsg->cm_fields['M'] = realloc(bmsg->cm_fields['M'],
1469                                 (strlen(bmsg->cm_fields['M']) + omsgsize + 1024) );
1470                 strcat(bmsg->cm_fields['M'], omsgtext);
1471                 free(omsgtext);
1472         }
1473
1474         /* Close the multipart MIME scope */
1475         strcat(bmsg->cm_fields['M'], "--");
1476         strcat(bmsg->cm_fields['M'], boundary);
1477         strcat(bmsg->cm_fields['M'], "--\r\n");
1478
1479         /* Deliver the bounce if there's anything worth mentioning */
1480         CtdlLogPrintf(CTDL_DEBUG, "num_bounces = %d\n", num_bounces);
1481         if (num_bounces > 0) {
1482
1483                 /* First try the user who sent the message */
1484                 CtdlLogPrintf(CTDL_DEBUG, "bounce to user? <%s>\n", bounceto);
1485                 if (IsEmptyStr(bounceto)) {
1486                         CtdlLogPrintf(CTDL_ERR, "No bounce address specified\n");
1487                         bounce_msgid = (-1L);
1488                 }
1489
1490                 /* Can we deliver the bounce to the original sender? */
1491                 valid = validate_recipients(bounceto, smtp_get_Recipients (), 0);
1492                 if (valid != NULL) {
1493                         if (valid->num_error == 0) {
1494                                 CtdlSubmitMsg(bmsg, valid, "", QP_EADDR);
1495                                 successful_bounce = 1;
1496                         }
1497                 }
1498
1499                 /* If not, post it in the Aide> room */
1500                 if (successful_bounce == 0) {
1501                         CtdlSubmitMsg(bmsg, NULL, config.c_aideroom, QP_EADDR);
1502                 }
1503
1504                 /* Free up the memory we used */
1505                 if (valid != NULL) {
1506                         free_recipients(valid);
1507                 }
1508         }
1509
1510         CtdlFreeMessage(bmsg);
1511         CtdlLogPrintf(CTDL_DEBUG, "Done processing bounces\n");
1512 }
1513
1514
1515 /*
1516  * smtp_purge_completed_deliveries() is caled by smtp_do_procmsg() to scan a
1517  * set of delivery instructions for completed deliveries and remove them.
1518  *
1519  * It returns the number of incomplete deliveries remaining.
1520  */
1521 int smtp_purge_completed_deliveries(char *instr) {
1522         int i;
1523         int lines;
1524         int status;
1525         char buf[1024];
1526         char key[1024];
1527         char addr[1024];
1528         char dsn[1024];
1529         int completed;
1530         int incomplete = 0;
1531
1532         lines = num_tokens(instr, '\n');
1533         for (i=0; i<lines; ++i) {
1534                 extract_token(buf, instr, i, '\n', sizeof buf);
1535                 extract_token(key, buf, 0, '|', sizeof key);
1536                 extract_token(addr, buf, 1, '|', sizeof addr);
1537                 status = extract_int(buf, 2);
1538                 extract_token(dsn, buf, 3, '|', sizeof dsn);
1539
1540                 completed = 0;
1541
1542                 if (!strcasecmp(key, "remote")) {
1543                         if (status == 2) completed = 1;
1544                         else ++incomplete;
1545                 }
1546
1547                 if (completed) {
1548                         remove_token(instr, i, '\n');
1549                         --i;
1550                         --lines;
1551                 }
1552         }
1553
1554         return(incomplete);
1555 }
1556
1557
1558 /*
1559  * smtp_do_procmsg()
1560  *
1561  * Called by smtp_do_queue() to handle an individual message.
1562  */
1563 void smtp_do_procmsg(long msgnum, void *userdata) {
1564         struct CtdlMessage *msg = NULL;
1565         char *instr = NULL;
1566         char *results = NULL;
1567         int i;
1568         int lines;
1569         int status;
1570         char buf[1024];
1571         char key[1024];
1572         char addr[1024];
1573         char dsn[1024];
1574         char envelope_from[1024];
1575         long text_msgid = (-1);
1576         int incomplete_deliveries_remaining;
1577         time_t attempted = 0L;
1578         time_t last_attempted = 0L;
1579         time_t retry = SMTP_RETRY_INTERVAL;
1580
1581         CtdlLogPrintf(CTDL_DEBUG, "SMTP client: smtp_do_procmsg(%ld)\n", msgnum);
1582         strcpy(envelope_from, "");
1583
1584         msg = CtdlFetchMessage(msgnum, 1);
1585         if (msg == NULL) {
1586                 CtdlLogPrintf(CTDL_ERR, "SMTP client: tried %ld but no such message!\n", msgnum);
1587                 return;
1588         }
1589
1590         instr = strdup(msg->cm_fields['M']);
1591         CtdlFreeMessage(msg);
1592
1593         /* Strip out the headers amd any other non-instruction line */
1594         lines = num_tokens(instr, '\n');
1595         for (i=0; i<lines; ++i) {
1596                 extract_token(buf, instr, i, '\n', sizeof buf);
1597                 if (num_tokens(buf, '|') < 2) {
1598                         remove_token(instr, i, '\n');
1599                         --lines;
1600                         --i;
1601                 }
1602         }
1603
1604         /* Learn the message ID and find out about recent delivery attempts */
1605         lines = num_tokens(instr, '\n');
1606         for (i=0; i<lines; ++i) {
1607                 extract_token(buf, instr, i, '\n', sizeof buf);
1608                 extract_token(key, buf, 0, '|', sizeof key);
1609                 if (!strcasecmp(key, "msgid")) {
1610                         text_msgid = extract_long(buf, 1);
1611                 }
1612                 if (!strcasecmp(key, "envelope_from")) {
1613                         extract_token(envelope_from, buf, 1, '|', sizeof envelope_from);
1614                 }
1615                 if (!strcasecmp(key, "retry")) {
1616                         /* double the retry interval after each attempt */
1617                         retry = extract_long(buf, 1) * 2L;
1618                         if (retry > SMTP_RETRY_MAX) {
1619                                 retry = SMTP_RETRY_MAX;
1620                         }
1621                         remove_token(instr, i, '\n');
1622                 }
1623                 if (!strcasecmp(key, "attempted")) {
1624                         attempted = extract_long(buf, 1);
1625                         if (attempted > last_attempted)
1626                                 last_attempted = attempted;
1627                 }
1628         }
1629
1630         /*
1631          * Postpone delivery if we've already tried recently.
1632          */
1633         if (((time(NULL) - last_attempted) < retry) && (run_queue_now == 0)) {
1634                 CtdlLogPrintf(CTDL_DEBUG, "SMTP client: Retry time not yet reached.\n");
1635                 free(instr);
1636                 return;
1637         }
1638
1639
1640         /*
1641          * Bail out if there's no actual message associated with this
1642          */
1643         if (text_msgid < 0L) {
1644                 CtdlLogPrintf(CTDL_ERR, "SMTP client: no 'msgid' directive found!\n");
1645                 free(instr);
1646                 return;
1647         }
1648
1649         /* Plow through the instructions looking for 'remote' directives and
1650          * a status of 0 (no delivery yet attempted) or 3/4 (transient errors
1651          * were experienced and it's time to try again)
1652          */
1653         lines = num_tokens(instr, '\n');
1654         for (i=0; i<lines; ++i) {
1655                 extract_token(buf, instr, i, '\n', sizeof buf);
1656                 extract_token(key, buf, 0, '|', sizeof key);
1657                 extract_token(addr, buf, 1, '|', sizeof addr);
1658                 status = extract_int(buf, 2);
1659                 extract_token(dsn, buf, 3, '|', sizeof dsn);
1660                 if ( (!strcasecmp(key, "remote"))
1661                    && ((status==0)||(status==3)||(status==4)) ) {
1662
1663                         /* Remove this "remote" instruction from the set,
1664                          * but replace the set's final newline if
1665                          * remove_token() stripped it.  It has to be there.
1666                          */
1667                         remove_token(instr, i, '\n');
1668                         if (instr[strlen(instr)-1] != '\n') {
1669                                 strcat(instr, "\n");
1670                         }
1671
1672                         --i;
1673                         --lines;
1674                         CtdlLogPrintf(CTDL_DEBUG, "SMTP client: Trying <%s>\n", addr);
1675                         smtp_try(key, addr, &status, dsn, sizeof dsn, text_msgid, envelope_from);
1676                         if (status != 2) {
1677                                 if (results == NULL) {
1678                                         results = malloc(1024);
1679                                         memset(results, 0, 1024);
1680                                 }
1681                                 else {
1682                                         results = realloc(results, strlen(results) + 1024);
1683                                 }
1684                                 snprintf(&results[strlen(results)], 1024,
1685                                         "%s|%s|%d|%s\n",
1686                                         key, addr, status, dsn);
1687                         }
1688                 }
1689         }
1690
1691         if (results != NULL) {
1692                 instr = realloc(instr, strlen(instr) + strlen(results) + 2);
1693                 strcat(instr, results);
1694                 free(results);
1695         }
1696
1697
1698         /* Generate 'bounce' messages */
1699         smtp_do_bounce(instr);
1700
1701         /* Go through the delivery list, deleting completed deliveries */
1702         incomplete_deliveries_remaining =
1703                 smtp_purge_completed_deliveries(instr);
1704
1705
1706         /*
1707          * No delivery instructions remain, so delete both the instructions
1708          * message and the message message.
1709          */
1710         if (incomplete_deliveries_remaining <= 0) {
1711                 long delmsgs[2];
1712                 delmsgs[0] = msgnum;
1713                 delmsgs[1] = text_msgid;
1714                 CtdlDeleteMessages(SMTP_SPOOLOUT_ROOM, delmsgs, 2, "");
1715         }
1716
1717         /*
1718          * Uncompleted delivery instructions remain, so delete the old
1719          * instructions and replace with the updated ones.
1720          */
1721         if (incomplete_deliveries_remaining > 0) {
1722                 CtdlDeleteMessages(SMTP_SPOOLOUT_ROOM, &msgnum, 1, "");
1723                 msg = malloc(sizeof(struct CtdlMessage));
1724                 memset(msg, 0, sizeof(struct CtdlMessage));
1725                 msg->cm_magic = CTDLMESSAGE_MAGIC;
1726                 msg->cm_anon_type = MES_NORMAL;
1727                 msg->cm_format_type = FMT_RFC822;
1728                 msg->cm_fields['M'] = malloc(strlen(instr)+SIZ);
1729                 snprintf(msg->cm_fields['M'],
1730                         strlen(instr)+SIZ,
1731                         "Content-type: %s\n\n%s\n"
1732                         "attempted|%ld\n"
1733                         "retry|%ld\n",
1734                         SPOOLMIME, instr, (long)time(NULL), (long)retry );
1735                 CtdlSubmitMsg(msg, NULL, SMTP_SPOOLOUT_ROOM, QP_EADDR);
1736                 CtdlFreeMessage(msg);
1737         }
1738
1739         free(instr);
1740 }
1741
1742
1743
1744
1745 /*
1746  * smtp_do_queue()
1747  *
1748  * Run through the queue sending out messages.
1749  */
1750 void *smtp_do_queue(void *arg) {
1751         int num_processed = 0;
1752         struct CitContext smtp_queue_CC;
1753
1754         CtdlLogPrintf(CTDL_INFO, "SMTP client: processing outbound queue\n");
1755
1756         CtdlFillSystemContext(&smtp_queue_CC, "SMTP Send");
1757         citthread_setspecific(MyConKey, (void *)&smtp_queue_CC );
1758
1759         if (CtdlGetRoom(&CC->room, SMTP_SPOOLOUT_ROOM) != 0) {
1760                 CtdlLogPrintf(CTDL_ERR, "Cannot find room <%s>\n", SMTP_SPOOLOUT_ROOM);
1761         }
1762         else {
1763                 num_processed = CtdlForEachMessage(MSGS_ALL, 0L, NULL, SPOOLMIME, NULL, smtp_do_procmsg, NULL);
1764         }
1765
1766         citthread_mutex_unlock (&smtp_send_lock);
1767         CtdlLogPrintf(CTDL_INFO, "SMTP client: queue run completed; %d messages processed\n", num_processed);
1768         return(NULL);
1769 }
1770
1771
1772
1773 /*
1774  * smtp_queue_thread
1775  *
1776  * Create a thread to run the SMTP queue
1777  *
1778  * This was created as a response to a situation seen on Uncensored where a bad remote was holding
1779  * up SMTP sending for long times.
1780  * Converting to a thread does not fix the problem caused by the bad remote but it does prevent
1781  * the SMTP sending from stopping housekeeping and the EVT_TIMER event system which in turn prevented
1782  * other things from happening.
1783  */
1784 void smtp_queue_thread (void)
1785 {
1786         if (citthread_mutex_trylock (&smtp_send_lock)) {
1787                 CtdlLogPrintf(CTDL_DEBUG, "SMTP queue run already in progress\n");
1788         }
1789         else {
1790                 CtdlThreadCreate("SMTP Send", CTDLTHREAD_BIGSTACK, smtp_do_queue, NULL);
1791         }
1792 }
1793
1794
1795
1796 void smtp_server_going_down (void)
1797 {
1798         CtdlLogPrintf(CTDL_DEBUG, "SMTP module clean up for shutdown.\n");
1799
1800         citthread_mutex_destroy (&smtp_send_lock);
1801 }
1802
1803
1804
1805 /*****************************************************************************/
1806 /*                          SMTP UTILITY COMMANDS                            */
1807 /*****************************************************************************/
1808
1809 void cmd_smtp(char *argbuf) {
1810         char cmd[64];
1811         char node[256];
1812         char buf[1024];
1813         int i;
1814         int num_mxhosts;
1815
1816         if (CtdlAccessCheck(ac_aide)) return;
1817
1818         extract_token(cmd, argbuf, 0, '|', sizeof cmd);
1819
1820         if (!strcasecmp(cmd, "mx")) {
1821                 extract_token(node, argbuf, 1, '|', sizeof node);
1822                 num_mxhosts = getmx(buf, node);
1823                 cprintf("%d %d MX hosts listed for %s\n",
1824                         LISTING_FOLLOWS, num_mxhosts, node);
1825                 for (i=0; i<num_mxhosts; ++i) {
1826                         extract_token(node, buf, i, '|', sizeof node);
1827                         cprintf("%s\n", node);
1828                 }
1829                 cprintf("000\n");
1830                 return;
1831         }
1832
1833         else if (!strcasecmp(cmd, "runqueue")) {
1834                 run_queue_now = 1;
1835                 cprintf("%d All outbound SMTP will be retried now.\n", CIT_OK);
1836                 return;
1837         }
1838
1839         else {
1840                 cprintf("%d Invalid command.\n", ERROR + ILLEGAL_VALUE);
1841         }
1842
1843 }
1844
1845
1846 /*
1847  * Initialize the SMTP outbound queue
1848  */
1849 void smtp_init_spoolout(void) {
1850         struct ctdlroom qrbuf;
1851
1852         /*
1853          * Create the room.  This will silently fail if the room already
1854          * exists, and that's perfectly ok, because we want it to exist.
1855          */
1856         CtdlCreateRoom(SMTP_SPOOLOUT_ROOM, 3, "", 0, 1, 0, VIEW_MAILBOX);
1857
1858         /*
1859          * Make sure it's set to be a "system room" so it doesn't show up
1860          * in the <K>nown rooms list for Aides.
1861          */
1862         if (CtdlGetRoomLock(&qrbuf, SMTP_SPOOLOUT_ROOM) == 0) {
1863                 qrbuf.QRflags2 |= QR2_SYSTEM;
1864                 CtdlPutRoomLock(&qrbuf);
1865         }
1866 }
1867
1868
1869
1870
1871 /*****************************************************************************/
1872 /*                      MODULE INITIALIZATION STUFF                          */
1873 /*****************************************************************************/
1874 /*
1875  * This cleanup function blows away the temporary memory used by
1876  * the SMTP server.
1877  */
1878 void smtp_cleanup_function(void) {
1879
1880         /* Don't do this stuff if this is not an SMTP session! */
1881         if (CC->h_command_function != smtp_command_loop) return;
1882
1883         CtdlLogPrintf(CTDL_DEBUG, "Performing SMTP cleanup hook\n");
1884         free(SMTP);
1885 }
1886
1887
1888
1889 const char *CitadelServiceSMTP_MTA="SMTP-MTA";
1890 const char *CitadelServiceSMTPS_MTA="SMTPs-MTA";
1891 const char *CitadelServiceSMTP_MSA="SMTP-MSA";
1892 const char *CitadelServiceSMTP_LMTP="LMTP";
1893 const char *CitadelServiceSMTP_LMTP_UNF="LMTP-UnF";
1894
1895 CTDL_MODULE_INIT(smtp)
1896 {
1897         if (!threading)
1898         {
1899                 CtdlRegisterServiceHook(config.c_smtp_port,     /* SMTP MTA */
1900                                         NULL,
1901                                         smtp_mta_greeting,
1902                                         smtp_command_loop,
1903                                         NULL,
1904                                         CitadelServiceSMTP_MTA);
1905
1906 #ifdef HAVE_OPENSSL
1907                 CtdlRegisterServiceHook(config.c_smtps_port,
1908                                         NULL,
1909                                         smtps_greeting,
1910                                         smtp_command_loop,
1911                                         NULL,
1912                                         CitadelServiceSMTPS_MTA);
1913 #endif
1914
1915                 CtdlRegisterServiceHook(config.c_msa_port,      /* SMTP MSA */
1916                                         NULL,
1917                                         smtp_msa_greeting,
1918                                         smtp_command_loop,
1919                                         NULL,
1920                                         CitadelServiceSMTP_MSA);
1921
1922                 CtdlRegisterServiceHook(0,                      /* local LMTP */
1923                                         file_lmtp_socket,
1924                                         lmtp_greeting,
1925                                         smtp_command_loop,
1926                                         NULL,
1927                                         CitadelServiceSMTP_LMTP);
1928
1929                 CtdlRegisterServiceHook(0,                      /* local LMTP */
1930                                         file_lmtp_unfiltered_socket,
1931                                         lmtp_unfiltered_greeting,
1932                                         smtp_command_loop,
1933                                         NULL,
1934                                         CitadelServiceSMTP_LMTP_UNF);
1935
1936                 smtp_init_spoolout();
1937                 CtdlRegisterSessionHook(smtp_queue_thread, EVT_TIMER);
1938                 CtdlRegisterSessionHook(smtp_cleanup_function, EVT_STOP);
1939                 CtdlRegisterProtoHook(cmd_smtp, "SMTP", "SMTP utility commands");
1940                 CtdlRegisterCleanupHook (smtp_server_going_down);
1941                 citthread_mutex_init (&smtp_send_lock, NULL);
1942         }
1943
1944         /* return our Subversion id for the Log */
1945         return "$Id$";
1946 }