citadel/modules/smtp/serv_smtp.c

   1 /*
   2  * This module is an SMTP and ESMTP implementation for the Citadel system.
   3  * It is compliant with all of the following:
   4  *
   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
  19  *
  20  * The VRFY and EXPN commands have been removed from this implementation
  21  * because nobody uses these commands anymore, except for spammers.
  22  *
  23  * Copyright (c) 1998-2009 by the citadel.org team
  24  *
  25  *  This program is free software; you can redistribute it and/or modify
  26  *  it under the terms of the GNU General Public License as published by
  27  *  the Free Software Foundation; either version 3 of the License, or
  28  *  (at your option) any later version.
  29  *
  30  *  This program is distributed in the hope that it will be useful,
  31  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  32  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  33  *  GNU General Public License for more details.
  34  *
  35  *  You should have received a copy of the GNU General Public License
  36  *  along with this program; if not, write to the Free Software
  37  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  38  */
  39
  40 #include "sysdep.h"
  41 #include <stdlib.h>
  42 #include <unistd.h>
  43 #include <stdio.h>
  44 #include <termios.h>
  45 #include <fcntl.h>
  46 #include <signal.h>
  47 #include <pwd.h>
  48 #include <errno.h>
  49 #include <sys/types.h>
  50 #include <syslog.h>
  51
  52 #if TIME_WITH_SYS_TIME
  53 # include <sys/time.h>
  54 # include <time.h>
  55 #else
  56 # if HAVE_SYS_TIME_H
  57 #  include <sys/time.h>
  58 # else
  59 #  include <time.h>
  60 # endif
  61 #endif
  62
  63 #include <sys/wait.h>
  64 #include <ctype.h>
  65 #include <string.h>
  66 #include <limits.h>
  67 #include <sys/socket.h>
  68 #include <netinet/in.h>
  69 #include <arpa/inet.h>
  70 #include <libcitadel.h>
  71 #include "citadel.h"
  72 #include "server.h"
  73 #include "citserver.h"
  74 #include "support.h"
  75 #include "config.h"
  76 #include "control.h"
  77 #include "user_ops.h"
  78 #include "database.h"
  79 #include "msgbase.h"
  80 #include "internet_addressing.h"
  81 #include "genstamp.h"
  82 #include "domain.h"
  83 #include "clientsocket.h"
  84 #include "locate_host.h"
  85 #include "citadel_dirs.h"
  86
  87
  88
  89 #ifndef HAVE_SNPRINTF
  90 #include "snprintf.h"
  91 #endif
  92
  93
  94 #include "ctdl_module.h"
  95
  96
  97
  98 typedef struct _citsmtp {               /* Information about the current session */
  99         int command_state;
 100         char helo_node[SIZ];
 101         char from[SIZ];
 102         char recipients[SIZ];
 103         int number_of_recipients;
 104         int delivery_mode;
 105         int message_originated_locally;
 106         int is_lmtp;
 107         int is_unfiltered;
 108         int is_msa;
 109 }citsmtp;
 110
 111 enum {                          /* Command states for login authentication */
 112         smtp_command,
 113         smtp_user,
 114         smtp_password,
 115         smtp_plain
 116 };
 117
 118 #define SMTP            ((citsmtp *)CC->session_specific_data)
 119
 120
 121 int run_queue_now = 0;  /* Set to 1 to ignore SMTP send retry times */
 122
 123
 124 /*****************************************************************************/
 125 /*                      SMTP SERVER (INBOUND) STUFF                          */
 126 /*****************************************************************************/
 127
 128
 129 /*
 130  * Here's where our SMTP session begins its happy day.
 131  */
 132 void smtp_greeting(int is_msa)
 133 {
 134         citsmtp *sSMTP;
 135         char message_to_spammer[1024];
 136
 137         strcpy(CC->cs_clientname, "SMTP session");
 138         CC->internal_pgm = 1;
 139         CC->cs_flags |= CS_STEALTH;
 140         CC->session_specific_data = malloc(sizeof(citsmtp));
 141         memset(SMTP, 0, sizeof(citsmtp));
 142         sSMTP = SMTP;
 143         sSMTP->is_msa = is_msa;
 144
 145         /* If this config option is set, reject connections from problem
 146          * addresses immediately instead of after they execute a RCPT
 147          */
 148         if ( (config.c_rbl_at_greeting) && (sSMTP->is_msa == 0) ) {
 149                 if (rbl_check(message_to_spammer)) {
 150                         if (CtdlThreadCheckStop())
 151                                 cprintf("421 %s\r\n", message_to_spammer);
 152                         else
 153                                 cprintf("550 %s\r\n", message_to_spammer);
 154                         CC->kill_me = 1;
 155                         /* no need to free_recipients(valid), it's not allocated yet */
 156                         return;
 157                 }
 158         }
 159
 160         /* Otherwise we're either clean or we check later. */
 161
 162         if (CC->nologin==1) {
 163                 cprintf("500 Too many users are already online (maximum is %d)\r\n",
 164                         config.c_maxsessions
 165                 );
 166                 CC->kill_me = 1;
 167                 /* no need to free_recipients(valid), it's not allocated yet */
 168                 return;
 169         }
 170
 171         /* Note: the FQDN *must* appear as the first thing after the 220 code.
 172          * Some clients (including citmail.c) depend on it being there.
 173          */
 174         cprintf("220 %s ESMTP Citadel server ready.\r\n", config.c_fqdn);
 175 }
 176
 177
 178 /*
 179  * SMTPS is just like SMTP, except it goes crypto right away.
 180  */
 181 void smtps_greeting(void) {
 182         CtdlModuleStartCryptoMsgs(NULL, NULL, NULL);
 183 #ifdef HAVE_OPENSSL
 184         if (!CC->redirect_ssl) CC->kill_me = 1;         /* kill session if no crypto */
 185 #endif
 186         smtp_greeting(0);
 187 }
 188
 189
 190 /*
 191  * SMTP MSA port requires authentication.
 192  */
 193 void smtp_msa_greeting(void) {
 194         smtp_greeting(1);
 195 }
 196
 197
 198 /*
 199  * LMTP is like SMTP but with some extra bonus footage added.
 200  */
 201 void lmtp_greeting(void) {
 202         citsmtp *sSMTP;
 203
 204         smtp_greeting(0);
 205         sSMTP = SMTP;
 206         SMTP->is_lmtp = 1;
 207 }
 208
 209
 210 /*
 211  * Generic SMTP MTA greeting
 212  */
 213 void smtp_mta_greeting(void) {
 214         smtp_greeting(0);
 215 }
 216
 217
 218 /*
 219  * We also have an unfiltered LMTP socket that bypasses spam filters.
 220  */
 221 void lmtp_unfiltered_greeting(void) {
 222         citsmtp *sSMTP;
 223
 224         smtp_greeting(0);
 225         sSMTP = SMTP;
 226         sSMTP->is_lmtp = 1;
 227         sSMTP->is_unfiltered = 1;
 228 }
 229
 230
 231 /*
 232  * Login greeting common to all auth methods
 233  */
 234 void smtp_auth_greeting(void) {
 235                 cprintf("235 Hello, %s\r\n", CC->user.fullname);
 236                 CtdlLogPrintf(CTDL_NOTICE, "SMTP authenticated %s\n", CC->user.fullname);
 237                 CC->internal_pgm = 0;
 238                 CC->cs_flags &= ~CS_STEALTH;
 239 }
 240
 241
 242 /*
 243  * Implement HELO and EHLO commands.
 244  *
 245  * which_command:  0=HELO, 1=EHLO, 2=LHLO
 246  */
 247 void smtp_hello(char *argbuf, int which_command) {
 248         citsmtp *sSMTP = SMTP;
 249
 250         safestrncpy(sSMTP->helo_node, argbuf, sizeof sSMTP->helo_node);
 251
 252         if ( (which_command != 2) && (sSMTP->is_lmtp) ) {
 253                 cprintf("500 Only LHLO is allowed when running LMTP\r\n");
 254                 return;
 255         }
 256
 257         if ( (which_command == 2) && (sSMTP->is_lmtp == 0) ) {
 258                 cprintf("500 LHLO is only allowed when running LMTP\r\n");
 259                 return;
 260         }
 261
 262         if (which_command == 0) {
 263                 cprintf("250 Hello %s (%s [%s])\r\n",
 264                         sSMTP->helo_node,
 265                         CC->cs_host,
 266                         CC->cs_addr
 267                 );
 268         }
 269         else {
 270                 if (which_command == 1) {
 271                         cprintf("250-Hello %s (%s [%s])\r\n",
 272                                 sSMTP->helo_node,
 273                                 CC->cs_host,
 274                                 CC->cs_addr
 275                         );
 276                 }
 277                 else {
 278                         cprintf("250-Greetings and joyous salutations.\r\n");
 279                 }
 280                 cprintf("250-HELP\r\n");
 281                 cprintf("250-SIZE %ld\r\n", config.c_maxmsglen);
 282
 283 #ifdef HAVE_OPENSSL
 284                 /*
 285                  * Offer TLS, but only if TLS is not already active.
 286                  * Furthermore, only offer TLS when running on
 287                  * the SMTP-MSA port, not on the SMTP-MTA port, due to
 288                  * questionable reliability of TLS in certain sending MTA's.
 289                  */
 290                 if ( (!CC->redirect_ssl) && (sSMTP->is_msa) ) {
 291                         cprintf("250-STARTTLS\r\n");
 292                 }
 293 #endif  /* HAVE_OPENSSL */
 294
 295                 cprintf("250-AUTH LOGIN PLAIN\r\n"
 296                         "250-AUTH=LOGIN PLAIN\r\n"
 297                         "250 8BITMIME\r\n"
 298                 );
 299         }
 300 }
 301
 302
 303
 304 /*
 305  * Implement HELP command.
 306  */
 307 void smtp_help(void) {
 308         cprintf("214 RTFM http://www.ietf.org/rfc/rfc2821.txt\r\n");
 309 }
 310
 311
 312 /*
 313  *
 314  */
 315 void smtp_get_user(char *argbuf) {
 316         char buf[SIZ];
 317         char username[SIZ];
 318         citsmtp *sSMTP = SMTP;
 319
 320         CtdlDecodeBase64(username, argbuf, SIZ);
 321         /* CtdlLogPrintf(CTDL_DEBUG, "Trying <%s>\n", username); */
 322         if (CtdlLoginExistingUser(NULL, username) == login_ok) {
 323                 CtdlEncodeBase64(buf, "Password:", 9, 0);
 324                 cprintf("334 %s\r\n", buf);
 325                 sSMTP->command_state = smtp_password;
 326         }
 327         else {
 328                 cprintf("500 No such user.\r\n");
 329                 sSMTP->command_state = smtp_command;
 330         }
 331 }
 332
 333
 334 /*
 335  *
 336  */
 337 void smtp_get_pass(char *argbuf) {
 338         char password[SIZ];
 339         long len;
 340
 341         memset(password, 0, sizeof(password));
 342         len = CtdlDecodeBase64(password, argbuf, SIZ);
 343         /* CtdlLogPrintf(CTDL_DEBUG, "Trying <%s>\n", password); */
 344         if (CtdlTryPassword(password, len) == pass_ok) {
 345                 smtp_auth_greeting();
 346         }
 347         else {
 348                 cprintf("535 Authentication failed.\r\n");
 349         }
 350         SMTP->command_state = smtp_command;
 351 }
 352
 353
 354 /*
 355  * Back end for PLAIN auth method (either inline or multistate)
 356  */
 357 void smtp_try_plain(char *encoded_authstring) {
 358         char decoded_authstring[1024];
 359         char ident[256];
 360         char user[256];
 361         char pass[256];
 362         int result;
 363         long len;
 364
 365         CtdlDecodeBase64(decoded_authstring, encoded_authstring, strlen(encoded_authstring) );
 366         safestrncpy(ident, decoded_authstring, sizeof ident);
 367         safestrncpy(user, &decoded_authstring[strlen(ident) + 1], sizeof user);
 368         len = safestrncpy(pass, &decoded_authstring[strlen(ident) + strlen(user) + 2], sizeof pass);
 369         if (len == -1)
 370                 len = sizeof(pass) - 1;
 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, len) == 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 (defbody != 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         const char *ptr;
 979         size_t msg_size;
 980         int scan_done;
 981         CitContext *CCC=CC;
 982
 983
 984         /* Parse out the host portion of the recipient address */
 985         process_rfc822_addr(addr, user, node, name);
 986
 987         CtdlLogPrintf(CTDL_DEBUG, "SMTP client: Attempting delivery to <%s> @ <%s> (%s)\n",
 988                 user, node, name);
 989
 990         /* Load the message out of the database */
 991         CCC->redirect_buffer = NewStrBufPlain(NULL, SIZ);
 992         CtdlOutputMsg(msgnum, MT_RFC822, HEADERS_ALL, 0, 1, NULL, (ESC_DOT|SUPPRESS_ENV_TO) );
 993         msg_size = StrLength(CC->redirect_buffer);
 994         msgtext = SmashStrBuf(&CC->redirect_buffer);
 995
 996         /* If no envelope_from is supplied, extract one from the message */
 997         if ( (envelope_from == NULL) || (IsEmptyStr(envelope_from)) ) {
 998                 strcpy(mailfrom, "");
 999                 scan_done = 0;
1000                 ptr = msgtext;
1001                 do {
1002                         if (ptr = cmemreadline(ptr, buf, sizeof buf), *ptr == 0) {
1003                                 scan_done = 1;
1004                         }
1005                         if (!strncasecmp(buf, "From:", 5)) {
1006                                 safestrncpy(mailfrom, &buf[5], sizeof mailfrom);
1007                                 striplt(mailfrom);
1008                                 for (i=0; mailfrom[i]; ++i) {
1009                                         if (!isprint(mailfrom[i])) {
1010                                                 strcpy(&mailfrom[i], &mailfrom[i+1]);
1011                                                 i=0;
1012                                         }
1013                                 }
1014
1015                                 /* Strip out parenthesized names */
1016                                 lp = (-1);
1017                                 rp = (-1);
1018                                 for (i=0; mailfrom[i]; ++i) {
1019                                         if (mailfrom[i] == '(') lp = i;
1020                                         if (mailfrom[i] == ')') rp = i;
1021                                 }
1022                                 if ((lp>0)&&(rp>lp)) {
1023                                         strcpy(&mailfrom[lp-1], &mailfrom[rp+1]);
1024                                 }
1025
1026                                 /* Prefer brokketized names */
1027                                 lp = (-1);
1028                                 rp = (-1);
1029                                 for (i=0; mailfrom[i]; ++i) {
1030                                         if (mailfrom[i] == '<') lp = i;
1031                                         if (mailfrom[i] == '>') rp = i;
1032                                 }
1033                                 if ( (lp>=0) && (rp>lp) ) {
1034                                         mailfrom[rp] = 0;
1035                                         strcpy(mailfrom, &mailfrom[lp]);
1036                                 }
1037
1038                                 scan_done = 1;
1039                         }
1040                 } while (scan_done == 0);
1041                 if (IsEmptyStr(mailfrom)) strcpy(mailfrom, "someone@somewhere.org");
1042                 stripallbut(mailfrom, '<', '>');
1043                 envelope_from = mailfrom;
1044         }
1045
1046         /* Figure out what mail exchanger host we have to connect to */
1047         num_mxhosts = getmx(mxhosts, node);
1048         CtdlLogPrintf(CTDL_DEBUG, "Number of MX hosts for <%s> is %d [%s]\n", node, num_mxhosts, mxhosts);
1049         if (num_mxhosts < 1) {
1050                 *status = 5;
1051                 snprintf(dsn, SIZ, "No MX hosts found for <%s>", node);
1052                 return;
1053         }
1054
1055         sock = (-1);
1056         for (mx=0; (mx<num_mxhosts && sock < 0); ++mx) {
1057                 char *endpart;
1058                 extract_token(buf, mxhosts, mx, '|', sizeof buf);
1059                 strcpy(mx_user, "");
1060                 strcpy(mx_pass, "");
1061                 if (num_tokens(buf, '@') > 1) {
1062                         strcpy (mx_user, buf);
1063                         endpart = strrchr(mx_user, '@');
1064                         *endpart = '\0';
1065                         strcpy (mx_host, endpart + 1);
1066                         endpart = strrchr(mx_user, ':');
1067                         if (endpart != NULL) {
1068                                 strcpy(mx_pass, endpart+1);
1069                                 *endpart = '\0';
1070                         }
1071                 }
1072                 else
1073                         strcpy (mx_host, buf);
1074                 endpart = strrchr(mx_host, ':');
1075                 if (endpart != 0){
1076                         *endpart = '\0';
1077                         strcpy(mx_port, endpart + 1);
1078                 }
1079                 else {
1080                         strcpy(mx_port, "25");
1081                 }
1082                 CtdlLogPrintf(CTDL_DEBUG, "SMTP client: connecting to %s : %s ...\n", mx_host, mx_port);
1083                 sock = sock_connect(mx_host, mx_port);
1084                 snprintf(dsn, SIZ, "Could not connect: %s", strerror(errno));
1085                 if (sock >= 0)
1086                 {
1087                         CtdlLogPrintf(CTDL_DEBUG, "SMTP client: connected!\n");
1088                                 int fdflags;
1089                                 fdflags = fcntl(sock, F_GETFL);
1090                                 if (fdflags < 0)
1091                                         CtdlLogPrintf(CTDL_DEBUG,
1092                                                       "unable to get SMTP-Client socket flags! %s \n",
1093                                                       strerror(errno));
1094                                 fdflags = fdflags | O_NONBLOCK;
1095                                 if (fcntl(sock, F_SETFL, fdflags) < 0)
1096                                         CtdlLogPrintf(CTDL_DEBUG,
1097                                                       "unable to set SMTP-Client socket nonblocking flags! %s \n",
1098                                                       strerror(errno));
1099                 }
1100                 if (sock < 0) {
1101                         if (errno > 0) {
1102                                 snprintf(dsn, SIZ, "%s", strerror(errno));
1103                         }
1104                         else {
1105                                 snprintf(dsn, SIZ, "Unable to connect to %s : %s\n", mx_host, mx_port);
1106                         }
1107                 }
1108         }
1109
1110         if (sock < 0) {
1111                 *status = 4;    /* dsn is already filled in */
1112                 return;
1113         }
1114
1115         CCC->sReadBuf = NewStrBuf();
1116         CCC->sMigrateBuf = NewStrBuf();
1117         CCC->sPos = NULL;
1118
1119         /* Process the SMTP greeting from the server */
1120         if (ml_sock_gets(&sock, buf, 90) < 0) {
1121                 *status = 4;
1122                 strcpy(dsn, "Connection broken during SMTP conversation");
1123                 goto bail;
1124         }
1125         CtdlLogPrintf(CTDL_DEBUG, "<%s\n", buf);
1126         if (buf[0] != '2') {
1127                 if (buf[0] == '4') {
1128                         *status = 4;
1129                         safestrncpy(dsn, &buf[4], 1023);
1130                         goto bail;
1131                 }
1132                 else {
1133                         *status = 5;
1134                         safestrncpy(dsn, &buf[4], 1023);
1135                         goto bail;
1136                 }
1137         }
1138
1139         /* At this point we know we are talking to a real SMTP server */
1140
1141         /* Do a EHLO command.  If it fails, try the HELO command. */
1142         snprintf(buf, sizeof buf, "EHLO %s\r\n", config.c_fqdn);
1143         CtdlLogPrintf(CTDL_DEBUG, ">%s", buf);
1144         sock_write(&sock, buf, strlen(buf));
1145         if (ml_sock_gets(&sock, buf, 30) < 0) {
1146                 *status = 4;
1147                 strcpy(dsn, "Connection broken during SMTP HELO");
1148                 goto bail;
1149         }
1150         CtdlLogPrintf(CTDL_DEBUG, "<%s\n", buf);
1151         if (buf[0] != '2') {
1152                 snprintf(buf, sizeof buf, "HELO %s\r\n", config.c_fqdn);
1153                 CtdlLogPrintf(CTDL_DEBUG, ">%s", buf);
1154                 sock_write(&sock, buf, strlen(buf));
1155                 if (ml_sock_gets(&sock, buf, 30) < 0) {
1156                         *status = 4;
1157                         strcpy(dsn, "Connection broken during SMTP HELO");
1158                         goto bail;
1159                 }
1160         }
1161         if (buf[0] != '2') {
1162                 if (buf[0] == '4') {
1163                         *status = 4;
1164                         safestrncpy(dsn, &buf[4], 1023);
1165                         goto bail;
1166                 }
1167                 else {
1168                         *status = 5;
1169                         safestrncpy(dsn, &buf[4], 1023);
1170                         goto bail;
1171                 }
1172         }
1173
1174         /* Do an AUTH command if necessary */
1175         if (!IsEmptyStr(mx_user)) {
1176                 char encoded[1024];
1177                 sprintf(buf, "%s%c%s%c%s", mx_user, '\0', mx_user, '\0', mx_pass);
1178                 CtdlEncodeBase64(encoded, buf, strlen(mx_user) + strlen(mx_user) + strlen(mx_pass) + 2, 0);
1179                 snprintf(buf, sizeof buf, "AUTH PLAIN %s\r\n", encoded);
1180                 CtdlLogPrintf(CTDL_DEBUG, ">%s", buf);
1181                 sock_write(&sock, buf, strlen(buf));
1182                 if (ml_sock_gets(&sock, buf, 30) < 0) {
1183                         *status = 4;
1184                         strcpy(dsn, "Connection broken during SMTP AUTH");
1185                         goto bail;
1186                 }
1187                 CtdlLogPrintf(CTDL_DEBUG, "<%s\n", buf);
1188                 if (buf[0] != '2') {
1189                         if (buf[0] == '4') {
1190                                 *status = 4;
1191                                 safestrncpy(dsn, &buf[4], 1023);
1192                                 goto bail;
1193                         }
1194                         else {
1195                                 *status = 5;
1196                                 safestrncpy(dsn, &buf[4], 1023);
1197                                 goto bail;
1198                         }
1199                 }
1200         }
1201
1202         /* previous command succeeded, now try the MAIL FROM: command */
1203         snprintf(buf, sizeof buf, "MAIL FROM:<%s>\r\n", envelope_from);
1204         CtdlLogPrintf(CTDL_DEBUG, ">%s", buf);
1205         sock_write(&sock, buf, strlen(buf));
1206         if (ml_sock_gets(&sock, buf, 30) < 0) {
1207                 *status = 4;
1208                 strcpy(dsn, "Connection broken during SMTP MAIL");
1209                 goto bail;
1210         }
1211         CtdlLogPrintf(CTDL_DEBUG, "<%s\n", buf);
1212         if (buf[0] != '2') {
1213                 if (buf[0] == '4') {
1214                         *status = 4;
1215                         safestrncpy(dsn, &buf[4], 1023);
1216                         goto bail;
1217                 }
1218                 else {
1219                         *status = 5;
1220                         safestrncpy(dsn, &buf[4], 1023);
1221                         goto bail;
1222                 }
1223         }
1224
1225         /* MAIL succeeded, now try the RCPT To: command */
1226         snprintf(buf, sizeof buf, "RCPT TO:<%s@%s>\r\n", user, node);
1227         CtdlLogPrintf(CTDL_DEBUG, ">%s", buf);
1228         sock_write(&sock, buf, strlen(buf));
1229         if (ml_sock_gets(&sock, buf, 30) < 0) {
1230                 *status = 4;
1231                 strcpy(dsn, "Connection broken during SMTP RCPT");
1232                 goto bail;
1233         }
1234         CtdlLogPrintf(CTDL_DEBUG, "<%s\n", buf);
1235         if (buf[0] != '2') {
1236                 if (buf[0] == '4') {
1237                         *status = 4;
1238                         safestrncpy(dsn, &buf[4], 1023);
1239                         goto bail;
1240                 }
1241                 else {
1242                         *status = 5;
1243                         safestrncpy(dsn, &buf[4], 1023);
1244                         goto bail;
1245                 }
1246         }
1247
1248         /* RCPT succeeded, now try the DATA command */
1249         CtdlLogPrintf(CTDL_DEBUG, ">DATA\n");
1250         sock_write(&sock, "DATA\r\n", 6);
1251         if (ml_sock_gets(&sock, buf, 30) < 0) {
1252                 *status = 4;
1253                 strcpy(dsn, "Connection broken during SMTP DATA");
1254                 goto bail;
1255         }
1256         CtdlLogPrintf(CTDL_DEBUG, "<%s\n", buf);
1257         if (buf[0] != '3') {
1258                 if (buf[0] == '4') {
1259                         *status = 3;
1260                         safestrncpy(dsn, &buf[4], 1023);
1261                         goto bail;
1262                 }
1263                 else {
1264                         *status = 5;
1265                         safestrncpy(dsn, &buf[4], 1023);
1266                         goto bail;
1267                 }
1268         }
1269
1270         /* If we reach this point, the server is expecting data.*/
1271         sock_write_timeout(&sock,
1272                            msgtext,
1273                            msg_size,
1274                            (msg_size / 128) + 50);
1275         if (msgtext[msg_size-1] != 10) {
1276                 CtdlLogPrintf(CTDL_WARNING, "Possible problem: message did not "
1277                         "correctly terminate. (expecting 0x10, got 0x%02x)\n",
1278                                 buf[msg_size-1]);
1279                 sock_write(&sock, "\r\n", 2);
1280         }
1281
1282         sock_write(&sock, ".\r\n", 3);
1283         tcdrain(sock);
1284         if (ml_sock_gets(&sock, buf, 90) < 0) {
1285                 *status = 4;
1286                 strcpy(dsn, "Connection broken during SMTP message transmit");
1287                 goto bail;
1288         }
1289         CtdlLogPrintf(CTDL_DEBUG, "%s\n", buf);
1290         if (buf[0] != '2') {
1291                 if (buf[0] == '4') {
1292                         *status = 4;
1293                         safestrncpy(dsn, &buf[4], 1023);
1294                         goto bail;
1295                 }
1296                 else {
1297                         *status = 5;
1298                         safestrncpy(dsn, &buf[4], 1023);
1299                         goto bail;
1300                 }
1301         }
1302
1303         /* We did it! */
1304         safestrncpy(dsn, &buf[4], 1023);
1305         *status = 2;
1306
1307         CtdlLogPrintf(CTDL_DEBUG, ">QUIT\n");
1308         sock_write(&sock, "QUIT\r\n", 6);
1309         ml_sock_gets(&sock, buf, 30);
1310         CtdlLogPrintf(CTDL_DEBUG, "<%s\n", buf);
1311         CtdlLogPrintf(CTDL_INFO, "SMTP client: delivery to <%s> @ <%s> (%s) succeeded\n",
1312                 user, node, name);
1313
1314 bail:   free(msgtext);
1315         FreeStrBuf(&CCC->sReadBuf);
1316         FreeStrBuf(&CCC->sMigrateBuf);
1317         if (sock != -1)
1318                 sock_close(sock);
1319
1320         /* Write something to the syslog (which may or may not be where the
1321          * rest of the Citadel logs are going; some sysadmins want LOG_MAIL).
1322          */
1323         if (enable_syslog) {
1324                 syslog((LOG_MAIL | LOG_INFO),
1325                         "%ld: to=<%s>, relay=%s, stat=%s",
1326                         msgnum,
1327                         addr,
1328                         mx_host,
1329                         dsn
1330                 );
1331         }
1332
1333         return;
1334 }
1335
1336
1337
1338 /*
1339  * smtp_do_bounce() is caled by smtp_do_procmsg() to scan a set of delivery
1340  * instructions for "5" codes (permanent fatal errors) and produce/deliver
1341  * a "bounce" message (delivery status notification).
1342  */
1343 void smtp_do_bounce(char *instr) {
1344         int i;
1345         int lines;
1346         int status;
1347         char buf[1024];
1348         char key[1024];
1349         char addr[1024];
1350         char dsn[1024];
1351         char bounceto[1024];
1352         StrBuf *boundary;
1353         int num_bounces = 0;
1354         int bounce_this = 0;
1355         long bounce_msgid = (-1);
1356         time_t submitted = 0L;
1357         struct CtdlMessage *bmsg = NULL;
1358         int give_up = 0;
1359         struct recptypes *valid;
1360         int successful_bounce = 0;
1361         static int seq = 0;
1362         StrBuf *BounceMB;
1363         long omsgid = (-1);
1364
1365         CtdlLogPrintf(CTDL_DEBUG, "smtp_do_bounce() called\n");
1366         strcpy(bounceto, "");
1367         boundary = NewStrBufPlain(HKEY("=_Citadel_Multipart_"));
1368         StrBufAppendPrintf(boundary, "%s_%04x%04x", config.c_fqdn, getpid(), ++seq);
1369         lines = num_tokens(instr, '\n');
1370
1371         /* See if it's time to give up on delivery of this message */
1372         for (i=0; i<lines; ++i) {
1373                 extract_token(buf, instr, i, '\n', sizeof buf);
1374                 extract_token(key, buf, 0, '|', sizeof key);
1375                 extract_token(addr, buf, 1, '|', sizeof addr);
1376                 if (!strcasecmp(key, "submitted")) {
1377                         submitted = atol(addr);
1378                 }
1379         }
1380
1381         if ( (time(NULL) - submitted) > SMTP_GIVE_UP ) {
1382                 give_up = 1;
1383         }
1384
1385         /* Start building our bounce message */
1386
1387         bmsg = (struct CtdlMessage *) malloc(sizeof(struct CtdlMessage));
1388         if (bmsg == NULL) return;
1389         memset(bmsg, 0, sizeof(struct CtdlMessage));
1390         BounceMB = NewStrBufPlain(NULL, 1024);
1391
1392         bmsg->cm_magic = CTDLMESSAGE_MAGIC;
1393         bmsg->cm_anon_type = MES_NORMAL;
1394         bmsg->cm_format_type = FMT_RFC822;
1395         bmsg->cm_fields['A'] = strdup("Citadel");
1396         bmsg->cm_fields['O'] = strdup(MAILROOM);
1397         bmsg->cm_fields['N'] = strdup(config.c_nodename);
1398         bmsg->cm_fields['U'] = strdup("Delivery Status Notification (Failure)");
1399         StrBufAppendBufPlain(BounceMB, HKEY("Content-type: multipart/mixed; boundary=\""), 0);
1400         StrBufAppendBuf(BounceMB, boundary, 0);
1401         StrBufAppendBufPlain(BounceMB, HKEY("\"\r\n"), 0);
1402         StrBufAppendBufPlain(BounceMB, HKEY("MIME-Version: 1.0\r\n"), 0);
1403         StrBufAppendBufPlain(BounceMB, HKEY("X-Mailer: " CITADEL "\r\n"), 0);
1404         StrBufAppendBufPlain(BounceMB, HKEY("\r\nThis is a multipart message in MIME format.\r\n\r\n"), 0);
1405         StrBufAppendBufPlain(BounceMB, HKEY("--"), 0);
1406         StrBufAppendBuf(BounceMB, boundary, 0);
1407         StrBufAppendBufPlain(BounceMB, HKEY("\r\n"), 0);
1408         StrBufAppendBufPlain(BounceMB, HKEY("Content-type: text/plain\r\n\r\n"), 0);
1409
1410         if (give_up) StrBufAppendBufPlain(BounceMB, HKEY(
1411 "A message you sent could not be delivered to some or all of its recipients\n"
1412 "due to prolonged unavailability of its destination(s).\n"
1413 "Giving up on the following addresses:\n\n"
1414                                                   ), 0);
1415
1416         else StrBufAppendBufPlain(BounceMB, HKEY(
1417 "A message you sent could not be delivered to some or all of its recipients.\n"
1418 "The following addresses were undeliverable:\n\n"
1419                                           ), 0);
1420
1421         /*
1422          * Now go through the instructions checking for stuff.
1423          */
1424         for (i=0; i<lines; ++i) {
1425                 long addrlen;
1426                 long dsnlen;
1427                 extract_token(buf, instr, i, '\n', sizeof buf);
1428                 extract_token(key, buf, 0, '|', sizeof key);
1429                 addrlen = extract_token(addr, buf, 1, '|', sizeof addr);
1430                 status = extract_int(buf, 2);
1431                 dsnlen = extract_token(dsn, buf, 3, '|', sizeof dsn);
1432                 bounce_this = 0;
1433
1434                 CtdlLogPrintf(CTDL_DEBUG, "key=<%s> addr=<%s> status=%d dsn=<%s>\n",
1435                         key, addr, status, dsn);
1436
1437                 if (!strcasecmp(key, "bounceto")) {
1438                         strcpy(bounceto, addr);
1439                 }
1440
1441                 if (!strcasecmp(key, "msgid")) {
1442                         omsgid = atol(addr);
1443                 }
1444
1445                 if (!strcasecmp(key, "remote")) {
1446                         if (status == 5) bounce_this = 1;
1447                         if (give_up) bounce_this = 1;
1448                 }
1449
1450                 if (bounce_this) {
1451                         ++num_bounces;
1452
1453                         StrBufAppendBufPlain(BounceMB, addr, addrlen, 0);
1454                         StrBufAppendBufPlain(BounceMB, HKEY(": "), 0);
1455                         StrBufAppendBufPlain(BounceMB, dsn, dsnlen, 0);
1456                         StrBufAppendBufPlain(BounceMB, HKEY("\r\n"), 0);
1457
1458                         remove_token(instr, i, '\n');
1459                         --i;
1460                         --lines;
1461                 }
1462         }
1463
1464         /* Attach the original message */
1465         if (omsgid >= 0) {
1466                 StrBufAppendBufPlain(BounceMB, HKEY("--"), 0);
1467                 StrBufAppendBuf(BounceMB, boundary, 0);
1468                 StrBufAppendBufPlain(BounceMB, HKEY("\r\n"), 0);
1469                 StrBufAppendBufPlain(BounceMB, HKEY("Content-type: message/rfc822\r\n"), 0);
1470                 StrBufAppendBufPlain(BounceMB, HKEY("Content-Transfer-Encoding: 7bit\r\n"), 0);
1471                 StrBufAppendBufPlain(BounceMB, HKEY("Content-Disposition: inline\r\n"), 0);
1472                 StrBufAppendBufPlain(BounceMB, HKEY("\r\n"), 0);
1473
1474                 CC->redirect_buffer = NewStrBufPlain(NULL, SIZ);
1475                 CtdlOutputMsg(omsgid, MT_RFC822, HEADERS_ALL, 0, 1, NULL, 0);
1476                 StrBufAppendBuf(BounceMB, CC->redirect_buffer, 0);
1477                 FreeStrBuf(&CC->redirect_buffer);
1478         }
1479
1480         /* Close the multipart MIME scope */
1481         StrBufAppendBufPlain(BounceMB, HKEY("--"), 0);
1482         StrBufAppendBuf(BounceMB, boundary, 0);
1483         StrBufAppendBufPlain(BounceMB, HKEY("--\r\n"), 0);
1484         if (bmsg->cm_fields['A'] != NULL)
1485                 free(bmsg->cm_fields['A']);
1486         bmsg->cm_fields['A'] = SmashStrBuf(&BounceMB);
1487         /* Deliver the bounce if there's anything worth mentioning */
1488         CtdlLogPrintf(CTDL_DEBUG, "num_bounces = %d\n", num_bounces);
1489         if (num_bounces > 0) {
1490
1491                 /* First try the user who sent the message */
1492                 CtdlLogPrintf(CTDL_DEBUG, "bounce to user? <%s>\n", bounceto);
1493                 if (IsEmptyStr(bounceto)) {
1494                         CtdlLogPrintf(CTDL_ERR, "No bounce address specified\n");
1495                         bounce_msgid = (-1L);
1496                 }
1497
1498                 /* Can we deliver the bounce to the original sender? */
1499                 valid = validate_recipients(bounceto, smtp_get_Recipients (), 0);
1500                 if (valid != NULL) {
1501                         if (valid->num_error == 0) {
1502                                 CtdlSubmitMsg(bmsg, valid, "", QP_EADDR);
1503                                 successful_bounce = 1;
1504                         }
1505                 }
1506
1507                 /* If not, post it in the Aide> room */
1508                 if (successful_bounce == 0) {
1509                         CtdlSubmitMsg(bmsg, NULL, config.c_aideroom, QP_EADDR);
1510                 }
1511
1512                 /* Free up the memory we used */
1513                 if (valid != NULL) {
1514                         free_recipients(valid);
1515                 }
1516         }
1517         FreeStrBuf(&boundary);
1518         CtdlFreeMessage(bmsg);
1519         CtdlLogPrintf(CTDL_DEBUG, "Done processing bounces\n");
1520 }
1521
1522
1523 /*
1524  * smtp_purge_completed_deliveries() is caled by smtp_do_procmsg() to scan a
1525  * set of delivery instructions for completed deliveries and remove them.
1526  *
1527  * It returns the number of incomplete deliveries remaining.
1528  */
1529 int smtp_purge_completed_deliveries(char *instr) {
1530         int i;
1531         int lines;
1532         int status;
1533         char buf[1024];
1534         char key[1024];
1535         char addr[1024];
1536         char dsn[1024];
1537         int completed;
1538         int incomplete = 0;
1539
1540         lines = num_tokens(instr, '\n');
1541         for (i=0; i<lines; ++i) {
1542                 extract_token(buf, instr, i, '\n', sizeof buf);
1543                 extract_token(key, buf, 0, '|', sizeof key);
1544                 extract_token(addr, buf, 1, '|', sizeof addr);
1545                 status = extract_int(buf, 2);
1546                 extract_token(dsn, buf, 3, '|', sizeof dsn);
1547
1548                 completed = 0;
1549
1550                 if (!strcasecmp(key, "remote")) {
1551                         if (status == 2) completed = 1;
1552                         else ++incomplete;
1553                 }
1554
1555                 if (completed) {
1556                         remove_token(instr, i, '\n');
1557                         --i;
1558                         --lines;
1559                 }
1560         }
1561
1562         return(incomplete);
1563 }
1564
1565
1566 /*
1567  * smtp_do_procmsg()
1568  *
1569  * Called by smtp_do_queue() to handle an individual message.
1570  */
1571 void smtp_do_procmsg(long msgnum, void *userdata) {
1572         struct CtdlMessage *msg = NULL;
1573         char *instr = NULL;
1574         char *results = NULL;
1575         int i;
1576         int lines;
1577         int status;
1578         char buf[1024];
1579         char key[1024];
1580         char addr[1024];
1581         char dsn[1024];
1582         char envelope_from[1024];
1583         long text_msgid = (-1);
1584         int incomplete_deliveries_remaining;
1585         time_t attempted = 0L;
1586         time_t last_attempted = 0L;
1587         time_t retry = SMTP_RETRY_INTERVAL;
1588
1589         CtdlLogPrintf(CTDL_DEBUG, "SMTP client: smtp_do_procmsg(%ld)\n", msgnum);
1590         strcpy(envelope_from, "");
1591
1592         msg = CtdlFetchMessage(msgnum, 1);
1593         if (msg == NULL) {
1594                 CtdlLogPrintf(CTDL_ERR, "SMTP client: tried %ld but no such message!\n", msgnum);
1595                 return;
1596         }
1597
1598         instr = strdup(msg->cm_fields['M']);
1599         CtdlFreeMessage(msg);
1600
1601         /* Strip out the headers amd any other non-instruction line */
1602         lines = num_tokens(instr, '\n');
1603         for (i=0; i<lines; ++i) {
1604                 extract_token(buf, instr, i, '\n', sizeof buf);
1605                 if (num_tokens(buf, '|') < 2) {
1606                         remove_token(instr, i, '\n');
1607                         --lines;
1608                         --i;
1609                 }
1610         }
1611
1612         /* Learn the message ID and find out about recent delivery attempts */
1613         lines = num_tokens(instr, '\n');
1614         for (i=0; i<lines; ++i) {
1615                 extract_token(buf, instr, i, '\n', sizeof buf);
1616                 extract_token(key, buf, 0, '|', sizeof key);
1617                 if (!strcasecmp(key, "msgid")) {
1618                         text_msgid = extract_long(buf, 1);
1619                 }
1620                 if (!strcasecmp(key, "envelope_from")) {
1621                         extract_token(envelope_from, buf, 1, '|', sizeof envelope_from);
1622                 }
1623                 if (!strcasecmp(key, "retry")) {
1624                         /* double the retry interval after each attempt */
1625                         retry = extract_long(buf, 1) * 2L;
1626                         if (retry > SMTP_RETRY_MAX) {
1627                                 retry = SMTP_RETRY_MAX;
1628                         }
1629                         remove_token(instr, i, '\n');
1630                 }
1631                 if (!strcasecmp(key, "attempted")) {
1632                         attempted = extract_long(buf, 1);
1633                         if (attempted > last_attempted)
1634                                 last_attempted = attempted;
1635                 }
1636         }
1637
1638         /*
1639          * Postpone delivery if we've already tried recently.
1640          */
1641         if (((time(NULL) - last_attempted) < retry) && (run_queue_now == 0)) {
1642                 CtdlLogPrintf(CTDL_DEBUG, "SMTP client: Retry time not yet reached.\n");
1643                 free(instr);
1644                 return;
1645         }
1646
1647
1648         /*
1649          * Bail out if there's no actual message associated with this
1650          */
1651         if (text_msgid < 0L) {
1652                 CtdlLogPrintf(CTDL_ERR, "SMTP client: no 'msgid' directive found!\n");
1653                 free(instr);
1654                 return;
1655         }
1656
1657         /* Plow through the instructions looking for 'remote' directives and
1658          * a status of 0 (no delivery yet attempted) or 3/4 (transient errors
1659          * were experienced and it's time to try again)
1660          */
1661         lines = num_tokens(instr, '\n');
1662         for (i=0; i<lines; ++i) {
1663                 extract_token(buf, instr, i, '\n', sizeof buf);
1664                 extract_token(key, buf, 0, '|', sizeof key);
1665                 extract_token(addr, buf, 1, '|', sizeof addr);
1666                 status = extract_int(buf, 2);
1667                 extract_token(dsn, buf, 3, '|', sizeof dsn);
1668                 if ( (!strcasecmp(key, "remote"))
1669                    && ((status==0)||(status==3)||(status==4)) ) {
1670
1671                         /* Remove this "remote" instruction from the set,
1672                          * but replace the set's final newline if
1673                          * remove_token() stripped it.  It has to be there.
1674                          */
1675                         remove_token(instr, i, '\n');
1676                         if (instr[strlen(instr)-1] != '\n') {
1677                                 strcat(instr, "\n");
1678                         }
1679
1680                         --i;
1681                         --lines;
1682                         CtdlLogPrintf(CTDL_DEBUG, "SMTP client: Trying <%s>\n", addr);
1683                         smtp_try(key, addr, &status, dsn, sizeof dsn, text_msgid, envelope_from);
1684                         if (status != 2) {
1685                                 if (results == NULL) {
1686                                         results = malloc(1024);
1687                                         memset(results, 0, 1024);
1688                                 }
1689                                 else {
1690                                         results = realloc(results, strlen(results) + 1024);
1691                                 }
1692                                 snprintf(&results[strlen(results)], 1024,
1693                                         "%s|%s|%d|%s\n",
1694                                         key, addr, status, dsn);
1695                         }
1696                 }
1697         }
1698
1699         if (results != NULL) {
1700                 instr = realloc(instr, strlen(instr) + strlen(results) + 2);
1701                 strcat(instr, results);
1702                 free(results);
1703         }
1704
1705
1706         /* Generate 'bounce' messages */
1707         smtp_do_bounce(instr);
1708
1709         /* Go through the delivery list, deleting completed deliveries */
1710         incomplete_deliveries_remaining =
1711                 smtp_purge_completed_deliveries(instr);
1712
1713
1714         /*
1715          * No delivery instructions remain, so delete both the instructions
1716          * message and the message message.
1717          */
1718         if (incomplete_deliveries_remaining <= 0) {
1719                 long delmsgs[2];
1720                 delmsgs[0] = msgnum;
1721                 delmsgs[1] = text_msgid;
1722                 CtdlDeleteMessages(SMTP_SPOOLOUT_ROOM, delmsgs, 2, "");
1723         }
1724
1725         /*
1726          * Uncompleted delivery instructions remain, so delete the old
1727          * instructions and replace with the updated ones.
1728          */
1729         if (incomplete_deliveries_remaining > 0) {
1730                 CtdlDeleteMessages(SMTP_SPOOLOUT_ROOM, &msgnum, 1, "");
1731                 msg = malloc(sizeof(struct CtdlMessage));
1732                 memset(msg, 0, sizeof(struct CtdlMessage));
1733                 msg->cm_magic = CTDLMESSAGE_MAGIC;
1734                 msg->cm_anon_type = MES_NORMAL;
1735                 msg->cm_format_type = FMT_RFC822;
1736                 msg->cm_fields['M'] = malloc(strlen(instr)+SIZ);
1737                 snprintf(msg->cm_fields['M'],
1738                         strlen(instr)+SIZ,
1739                         "Content-type: %s\n\n%s\n"
1740                         "attempted|%ld\n"
1741                         "retry|%ld\n",
1742                         SPOOLMIME, instr, (long)time(NULL), (long)retry );
1743                 CtdlSubmitMsg(msg, NULL, SMTP_SPOOLOUT_ROOM, QP_EADDR);
1744                 CtdlFreeMessage(msg);
1745         }
1746
1747         free(instr);
1748 }
1749
1750
1751
1752
1753 /*
1754  * smtp_queue_thread()
1755  *
1756  * Run through the queue sending out messages.
1757  */
1758 void *smtp_queue_thread(void *arg) {
1759         int num_processed = 0;
1760         struct CitContext smtp_queue_CC;
1761
1762         CtdlFillSystemContext(&smtp_queue_CC, "SMTP Send");
1763         citthread_setspecific(MyConKey, (void *)&smtp_queue_CC);
1764         CtdlLogPrintf(CTDL_DEBUG, "smtp_queue_thread() initializing\n");
1765
1766         while (!CtdlThreadCheckStop()) {
1767
1768                 CtdlLogPrintf(CTDL_INFO, "SMTP client: processing outbound queue\n");
1769
1770                 if (CtdlGetRoom(&CC->room, SMTP_SPOOLOUT_ROOM) != 0) {
1771                         CtdlLogPrintf(CTDL_ERR, "Cannot find room <%s>\n", SMTP_SPOOLOUT_ROOM);
1772                 }
1773                 else {
1774                         num_processed = CtdlForEachMessage(MSGS_ALL, 0L, NULL, SPOOLMIME, NULL, smtp_do_procmsg, NULL);
1775                 }
1776                 CtdlLogPrintf(CTDL_INFO, "SMTP client: queue run completed; %d messages processed\n", num_processed);
1777                 CtdlThreadSleep(60);
1778         }
1779
1780         CtdlClearSystemContext();
1781         return(NULL);
1782 }
1783
1784
1785
1786 /*****************************************************************************/
1787 /*                          SMTP UTILITY COMMANDS                            */
1788 /*****************************************************************************/
1789
1790 void cmd_smtp(char *argbuf) {
1791         char cmd[64];
1792         char node[256];
1793         char buf[1024];
1794         int i;
1795         int num_mxhosts;
1796
1797         if (CtdlAccessCheck(ac_aide)) return;
1798
1799         extract_token(cmd, argbuf, 0, '|', sizeof cmd);
1800
1801         if (!strcasecmp(cmd, "mx")) {
1802                 extract_token(node, argbuf, 1, '|', sizeof node);
1803                 num_mxhosts = getmx(buf, node);
1804                 cprintf("%d %d MX hosts listed for %s\n",
1805                         LISTING_FOLLOWS, num_mxhosts, node);
1806                 for (i=0; i<num_mxhosts; ++i) {
1807                         extract_token(node, buf, i, '|', sizeof node);
1808                         cprintf("%s\n", node);
1809                 }
1810                 cprintf("000\n");
1811                 return;
1812         }
1813
1814         else if (!strcasecmp(cmd, "runqueue")) {
1815                 run_queue_now = 1;
1816                 cprintf("%d All outbound SMTP will be retried now.\n", CIT_OK);
1817                 return;
1818         }
1819
1820         else {
1821                 cprintf("%d Invalid command.\n", ERROR + ILLEGAL_VALUE);
1822         }
1823
1824 }
1825
1826
1827 /*
1828  * Initialize the SMTP outbound queue
1829  */
1830 void smtp_init_spoolout(void) {
1831         struct ctdlroom qrbuf;
1832
1833         /*
1834          * Create the room.  This will silently fail if the room already
1835          * exists, and that's perfectly ok, because we want it to exist.
1836          */
1837         CtdlCreateRoom(SMTP_SPOOLOUT_ROOM, 3, "", 0, 1, 0, VIEW_MAILBOX);
1838
1839         /*
1840          * Make sure it's set to be a "system room" so it doesn't show up
1841          * in the <K>nown rooms list for Aides.
1842          */
1843         if (CtdlGetRoomLock(&qrbuf, SMTP_SPOOLOUT_ROOM) == 0) {
1844                 qrbuf.QRflags2 |= QR2_SYSTEM;
1845                 CtdlPutRoomLock(&qrbuf);
1846         }
1847 }
1848
1849
1850
1851
1852 /*****************************************************************************/
1853 /*                      MODULE INITIALIZATION STUFF                          */
1854 /*****************************************************************************/
1855 /*
1856  * This cleanup function blows away the temporary memory used by
1857  * the SMTP server.
1858  */
1859 void smtp_cleanup_function(void) {
1860
1861         /* Don't do this stuff if this is not an SMTP session! */
1862         if (CC->h_command_function != smtp_command_loop) return;
1863
1864         CtdlLogPrintf(CTDL_DEBUG, "Performing SMTP cleanup hook\n");
1865         free(SMTP);
1866 }
1867
1868
1869
1870 const char *CitadelServiceSMTP_MTA="SMTP-MTA";
1871 const char *CitadelServiceSMTPS_MTA="SMTPs-MTA";
1872 const char *CitadelServiceSMTP_MSA="SMTP-MSA";
1873 const char *CitadelServiceSMTP_LMTP="LMTP";
1874 const char *CitadelServiceSMTP_LMTP_UNF="LMTP-UnF";
1875
1876 CTDL_MODULE_INIT(smtp)
1877 {
1878         if (!threading)
1879         {
1880                 CtdlRegisterServiceHook(config.c_smtp_port,     /* SMTP MTA */
1881                                         NULL,
1882                                         smtp_mta_greeting,
1883                                         smtp_command_loop,
1884                                         NULL,
1885                                         CitadelServiceSMTP_MTA);
1886
1887 #ifdef HAVE_OPENSSL
1888                 CtdlRegisterServiceHook(config.c_smtps_port,
1889                                         NULL,
1890                                         smtps_greeting,
1891                                         smtp_command_loop,
1892                                         NULL,
1893                                         CitadelServiceSMTPS_MTA);
1894 #endif
1895
1896                 CtdlRegisterServiceHook(config.c_msa_port,      /* SMTP MSA */
1897                                         NULL,
1898                                         smtp_msa_greeting,
1899                                         smtp_command_loop,
1900                                         NULL,
1901                                         CitadelServiceSMTP_MSA);
1902
1903                 CtdlRegisterServiceHook(0,                      /* local LMTP */
1904                                         file_lmtp_socket,
1905                                         lmtp_greeting,
1906                                         smtp_command_loop,
1907                                         NULL,
1908                                         CitadelServiceSMTP_LMTP);
1909
1910                 CtdlRegisterServiceHook(0,                      /* local LMTP */
1911                                         file_lmtp_unfiltered_socket,
1912                                         lmtp_unfiltered_greeting,
1913                                         smtp_command_loop,
1914                                         NULL,
1915                                         CitadelServiceSMTP_LMTP_UNF);
1916
1917                 smtp_init_spoolout();
1918                 CtdlRegisterSessionHook(smtp_cleanup_function, EVT_STOP);
1919                 CtdlRegisterProtoHook(cmd_smtp, "SMTP", "SMTP utility commands");
1920                 CtdlThreadCreate("SMTP Send", CTDLTHREAD_BIGSTACK, smtp_queue_thread, NULL);
1921         }
1922
1923         /* return our Subversion id for the Log */
1924         return "smtp";
1925 }