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, 5) < 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, 5) < 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, 5) < 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, 5) < 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, 5) < 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, 5) < 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, 5) < 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(&sock, msgtext, msg_size);
1272         if (msgtext[msg_size-1] != 10) {
1273                 CtdlLogPrintf(CTDL_WARNING, "Possible problem: message did not "
1274                         "correctly terminate. (expecting 0x10, got 0x%02x)\n",
1275                                 buf[msg_size-1]);
1276                 sock_write(&sock, "\r\n", 2);
1277         }
1278
1279         sock_write(&sock, ".\r\n", 3);
1280         tcdrain(sock);
1281         if (ml_sock_gets(&sock, buf, 90) < 0) {
1282                 *status = 4;
1283                 strcpy(dsn, "Connection broken during SMTP message transmit");
1284                 goto bail;
1285         }
1286         CtdlLogPrintf(CTDL_DEBUG, "%s\n", buf);
1287         if (buf[0] != '2') {
1288                 if (buf[0] == '4') {
1289                         *status = 4;
1290                         safestrncpy(dsn, &buf[4], 1023);
1291                         goto bail;
1292                 }
1293                 else {
1294                         *status = 5;
1295                         safestrncpy(dsn, &buf[4], 1023);
1296                         goto bail;
1297                 }
1298         }
1299
1300         /* We did it! */
1301         safestrncpy(dsn, &buf[4], 1023);
1302         *status = 2;
1303
1304         CtdlLogPrintf(CTDL_DEBUG, ">QUIT\n");
1305         sock_write(&sock, "QUIT\r\n", 6);
1306         ml_sock_gets(&sock, buf, 1);
1307         CtdlLogPrintf(CTDL_DEBUG, "<%s\n", buf);
1308         CtdlLogPrintf(CTDL_INFO, "SMTP client: delivery to <%s> @ <%s> (%s) succeeded\n",
1309                 user, node, name);
1310
1311 bail:   free(msgtext);
1312         FreeStrBuf(&CCC->sReadBuf);
1313         FreeStrBuf(&CCC->sMigrateBuf);
1314         if (sock != -1)
1315                 sock_close(sock);
1316
1317         /* Write something to the syslog (which may or may not be where the
1318          * rest of the Citadel logs are going; some sysadmins want LOG_MAIL).
1319          */
1320         if (enable_syslog) {
1321                 syslog((LOG_MAIL | LOG_INFO),
1322                         "%ld: to=<%s>, relay=%s, stat=%s",
1323                         msgnum,
1324                         addr,
1325                         mx_host,
1326                         dsn
1327                 );
1328         }
1329
1330         return;
1331 }
1332
1333
1334
1335 /*
1336  * smtp_do_bounce() is caled by smtp_do_procmsg() to scan a set of delivery
1337  * instructions for "5" codes (permanent fatal errors) and produce/deliver
1338  * a "bounce" message (delivery status notification).
1339  */
1340 void smtp_do_bounce(char *instr) {
1341         int i;
1342         int lines;
1343         int status;
1344         char buf[1024];
1345         char key[1024];
1346         char addr[1024];
1347         char dsn[1024];
1348         char bounceto[1024];
1349         StrBuf *boundary;
1350         int num_bounces = 0;
1351         int bounce_this = 0;
1352         long bounce_msgid = (-1);
1353         time_t submitted = 0L;
1354         struct CtdlMessage *bmsg = NULL;
1355         int give_up = 0;
1356         struct recptypes *valid;
1357         int successful_bounce = 0;
1358         static int seq = 0;
1359         StrBuf *BounceMB;
1360         long omsgid = (-1);
1361
1362         CtdlLogPrintf(CTDL_DEBUG, "smtp_do_bounce() called\n");
1363         strcpy(bounceto, "");
1364         boundary = NewStrBufPlain(HKEY("=_Citadel_Multipart_"));
1365         StrBufAppendPrintf(boundary, "%s_%04x%04x", config.c_fqdn, getpid(), ++seq);
1366         lines = num_tokens(instr, '\n');
1367
1368         /* See if it's time to give up on delivery of this message */
1369         for (i=0; i<lines; ++i) {
1370                 extract_token(buf, instr, i, '\n', sizeof buf);
1371                 extract_token(key, buf, 0, '|', sizeof key);
1372                 extract_token(addr, buf, 1, '|', sizeof addr);
1373                 if (!strcasecmp(key, "submitted")) {
1374                         submitted = atol(addr);
1375                 }
1376         }
1377
1378         if ( (time(NULL) - submitted) > SMTP_GIVE_UP ) {
1379                 give_up = 1;
1380         }
1381
1382         /* Start building our bounce message */
1383
1384         bmsg = (struct CtdlMessage *) malloc(sizeof(struct CtdlMessage));
1385         if (bmsg == NULL) return;
1386         memset(bmsg, 0, sizeof(struct CtdlMessage));
1387         BounceMB = NewStrBufPlain(NULL, 1024);
1388
1389         bmsg->cm_magic = CTDLMESSAGE_MAGIC;
1390         bmsg->cm_anon_type = MES_NORMAL;
1391         bmsg->cm_format_type = FMT_RFC822;
1392         bmsg->cm_fields['A'] = strdup("Citadel");
1393         bmsg->cm_fields['O'] = strdup(MAILROOM);
1394         bmsg->cm_fields['N'] = strdup(config.c_nodename);
1395         bmsg->cm_fields['U'] = strdup("Delivery Status Notification (Failure)");
1396         StrBufAppendBufPlain(BounceMB, HKEY("Content-type: multipart/mixed; boundary=\""), 0);
1397         StrBufAppendBuf(BounceMB, boundary, 0);
1398         StrBufAppendBufPlain(BounceMB, HKEY("\"\r\n"), 0);
1399         StrBufAppendBufPlain(BounceMB, HKEY("MIME-Version: 1.0\r\n"), 0);
1400         StrBufAppendBufPlain(BounceMB, HKEY("X-Mailer: " CITADEL "\r\n"), 0);
1401         StrBufAppendBufPlain(BounceMB, HKEY("\r\nThis is a multipart message in MIME format.\r\n\r\n"), 0);
1402         StrBufAppendBufPlain(BounceMB, HKEY("--"), 0);
1403         StrBufAppendBuf(BounceMB, boundary, 0);
1404         StrBufAppendBufPlain(BounceMB, HKEY("\r\n"), 0);
1405         StrBufAppendBufPlain(BounceMB, HKEY("Content-type: text/plain\r\n\r\n"), 0);
1406
1407         if (give_up) StrBufAppendBufPlain(BounceMB, HKEY(
1408 "A message you sent could not be delivered to some or all of its recipients\n"
1409 "due to prolonged unavailability of its destination(s).\n"
1410 "Giving up on the following addresses:\n\n"
1411                                                   ), 0);
1412
1413         else StrBufAppendBufPlain(BounceMB, HKEY(
1414 "A message you sent could not be delivered to some or all of its recipients.\n"
1415 "The following addresses were undeliverable:\n\n"
1416                                           ), 0);
1417
1418         /*
1419          * Now go through the instructions checking for stuff.
1420          */
1421         for (i=0; i<lines; ++i) {
1422                 long addrlen;
1423                 long dsnlen;
1424                 extract_token(buf, instr, i, '\n', sizeof buf);
1425                 extract_token(key, buf, 0, '|', sizeof key);
1426                 addrlen = extract_token(addr, buf, 1, '|', sizeof addr);
1427                 status = extract_int(buf, 2);
1428                 dsnlen = extract_token(dsn, buf, 3, '|', sizeof dsn);
1429                 bounce_this = 0;
1430
1431                 CtdlLogPrintf(CTDL_DEBUG, "key=<%s> addr=<%s> status=%d dsn=<%s>\n",
1432                         key, addr, status, dsn);
1433
1434                 if (!strcasecmp(key, "bounceto")) {
1435                         strcpy(bounceto, addr);
1436                 }
1437
1438                 if (!strcasecmp(key, "msgid")) {
1439                         omsgid = atol(addr);
1440                 }
1441
1442                 if (!strcasecmp(key, "remote")) {
1443                         if (status == 5) bounce_this = 1;
1444                         if (give_up) bounce_this = 1;
1445                 }
1446
1447                 if (bounce_this) {
1448                         ++num_bounces;
1449
1450                         StrBufAppendBufPlain(BounceMB, addr, addrlen, 0);
1451                         StrBufAppendBufPlain(BounceMB, HKEY(": "), 0);
1452                         StrBufAppendBufPlain(BounceMB, dsn, dsnlen, 0);
1453                         StrBufAppendBufPlain(BounceMB, HKEY("\r\n"), 0);
1454
1455                         remove_token(instr, i, '\n');
1456                         --i;
1457                         --lines;
1458                 }
1459         }
1460
1461         /* Attach the original message */
1462         if (omsgid >= 0) {
1463                 StrBufAppendBufPlain(BounceMB, HKEY("--"), 0);
1464                 StrBufAppendBuf(BounceMB, boundary, 0);
1465                 StrBufAppendBufPlain(BounceMB, HKEY("\r\n"), 0);
1466                 StrBufAppendBufPlain(BounceMB, HKEY("Content-type: message/rfc822\r\n"), 0);
1467                 StrBufAppendBufPlain(BounceMB, HKEY("Content-Transfer-Encoding: 7bit\r\n"), 0);
1468                 StrBufAppendBufPlain(BounceMB, HKEY("Content-Disposition: inline\r\n"), 0);
1469                 StrBufAppendBufPlain(BounceMB, HKEY("\r\n"), 0);
1470
1471                 CC->redirect_buffer = NewStrBufPlain(NULL, SIZ);
1472                 CtdlOutputMsg(omsgid, MT_RFC822, HEADERS_ALL, 0, 1, NULL, 0);
1473                 StrBufAppendBuf(BounceMB, CC->redirect_buffer, 0);
1474                 FreeStrBuf(&CC->redirect_buffer);
1475         }
1476
1477         /* Close the multipart MIME scope */
1478         StrBufAppendBufPlain(BounceMB, HKEY("--"), 0);
1479         StrBufAppendBuf(BounceMB, boundary, 0);
1480         StrBufAppendBufPlain(BounceMB, HKEY("--\r\n"), 0);
1481         bmsg->cm_fields['A'] = SmashStrBuf(&BounceMB);
1482         /* Deliver the bounce if there's anything worth mentioning */
1483         CtdlLogPrintf(CTDL_DEBUG, "num_bounces = %d\n", num_bounces);
1484         if (num_bounces > 0) {
1485
1486                 /* First try the user who sent the message */
1487                 CtdlLogPrintf(CTDL_DEBUG, "bounce to user? <%s>\n", bounceto);
1488                 if (IsEmptyStr(bounceto)) {
1489                         CtdlLogPrintf(CTDL_ERR, "No bounce address specified\n");
1490                         bounce_msgid = (-1L);
1491                 }
1492
1493                 /* Can we deliver the bounce to the original sender? */
1494                 valid = validate_recipients(bounceto, smtp_get_Recipients (), 0);
1495                 if (valid != NULL) {
1496                         if (valid->num_error == 0) {
1497                                 CtdlSubmitMsg(bmsg, valid, "", QP_EADDR);
1498                                 successful_bounce = 1;
1499                         }
1500                 }
1501
1502                 /* If not, post it in the Aide> room */
1503                 if (successful_bounce == 0) {
1504                         CtdlSubmitMsg(bmsg, NULL, config.c_aideroom, QP_EADDR);
1505                 }
1506
1507                 /* Free up the memory we used */
1508                 if (valid != NULL) {
1509                         free_recipients(valid);
1510                 }
1511         }
1512         FreeStrBuf(&boundary);
1513         CtdlFreeMessage(bmsg);
1514         CtdlLogPrintf(CTDL_DEBUG, "Done processing bounces\n");
1515 }
1516
1517
1518 /*
1519  * smtp_purge_completed_deliveries() is caled by smtp_do_procmsg() to scan a
1520  * set of delivery instructions for completed deliveries and remove them.
1521  *
1522  * It returns the number of incomplete deliveries remaining.
1523  */
1524 int smtp_purge_completed_deliveries(char *instr) {
1525         int i;
1526         int lines;
1527         int status;
1528         char buf[1024];
1529         char key[1024];
1530         char addr[1024];
1531         char dsn[1024];
1532         int completed;
1533         int incomplete = 0;
1534
1535         lines = num_tokens(instr, '\n');
1536         for (i=0; i<lines; ++i) {
1537                 extract_token(buf, instr, i, '\n', sizeof buf);
1538                 extract_token(key, buf, 0, '|', sizeof key);
1539                 extract_token(addr, buf, 1, '|', sizeof addr);
1540                 status = extract_int(buf, 2);
1541                 extract_token(dsn, buf, 3, '|', sizeof dsn);
1542
1543                 completed = 0;
1544
1545                 if (!strcasecmp(key, "remote")) {
1546                         if (status == 2) completed = 1;
1547                         else ++incomplete;
1548                 }
1549
1550                 if (completed) {
1551                         remove_token(instr, i, '\n');
1552                         --i;
1553                         --lines;
1554                 }
1555         }
1556
1557         return(incomplete);
1558 }
1559
1560
1561 /*
1562  * smtp_do_procmsg()
1563  *
1564  * Called by smtp_do_queue() to handle an individual message.
1565  */
1566 void smtp_do_procmsg(long msgnum, void *userdata) {
1567         struct CtdlMessage *msg = NULL;
1568         char *instr = NULL;
1569         char *results = NULL;
1570         int i;
1571         int lines;
1572         int status;
1573         char buf[1024];
1574         char key[1024];
1575         char addr[1024];
1576         char dsn[1024];
1577         char envelope_from[1024];
1578         long text_msgid = (-1);
1579         int incomplete_deliveries_remaining;
1580         time_t attempted = 0L;
1581         time_t last_attempted = 0L;
1582         time_t retry = SMTP_RETRY_INTERVAL;
1583
1584         CtdlLogPrintf(CTDL_DEBUG, "SMTP client: smtp_do_procmsg(%ld)\n", msgnum);
1585         strcpy(envelope_from, "");
1586
1587         msg = CtdlFetchMessage(msgnum, 1);
1588         if (msg == NULL) {
1589                 CtdlLogPrintf(CTDL_ERR, "SMTP client: tried %ld but no such message!\n", msgnum);
1590                 return;
1591         }
1592
1593         instr = strdup(msg->cm_fields['M']);
1594         CtdlFreeMessage(msg);
1595
1596         /* Strip out the headers amd any other non-instruction line */
1597         lines = num_tokens(instr, '\n');
1598         for (i=0; i<lines; ++i) {
1599                 extract_token(buf, instr, i, '\n', sizeof buf);
1600                 if (num_tokens(buf, '|') < 2) {
1601                         remove_token(instr, i, '\n');
1602                         --lines;
1603                         --i;
1604                 }
1605         }
1606
1607         /* Learn the message ID and find out about recent delivery attempts */
1608         lines = num_tokens(instr, '\n');
1609         for (i=0; i<lines; ++i) {
1610                 extract_token(buf, instr, i, '\n', sizeof buf);
1611                 extract_token(key, buf, 0, '|', sizeof key);
1612                 if (!strcasecmp(key, "msgid")) {
1613                         text_msgid = extract_long(buf, 1);
1614                 }
1615                 if (!strcasecmp(key, "envelope_from")) {
1616                         extract_token(envelope_from, buf, 1, '|', sizeof envelope_from);
1617                 }
1618                 if (!strcasecmp(key, "retry")) {
1619                         /* double the retry interval after each attempt */
1620                         retry = extract_long(buf, 1) * 2L;
1621                         if (retry > SMTP_RETRY_MAX) {
1622                                 retry = SMTP_RETRY_MAX;
1623                         }
1624                         remove_token(instr, i, '\n');
1625                 }
1626                 if (!strcasecmp(key, "attempted")) {
1627                         attempted = extract_long(buf, 1);
1628                         if (attempted > last_attempted)
1629                                 last_attempted = attempted;
1630                 }
1631         }
1632
1633         /*
1634          * Postpone delivery if we've already tried recently.
1635          */
1636         if (((time(NULL) - last_attempted) < retry) && (run_queue_now == 0)) {
1637                 CtdlLogPrintf(CTDL_DEBUG, "SMTP client: Retry time not yet reached.\n");
1638                 free(instr);
1639                 return;
1640         }
1641
1642
1643         /*
1644          * Bail out if there's no actual message associated with this
1645          */
1646         if (text_msgid < 0L) {
1647                 CtdlLogPrintf(CTDL_ERR, "SMTP client: no 'msgid' directive found!\n");
1648                 free(instr);
1649                 return;
1650         }
1651
1652         /* Plow through the instructions looking for 'remote' directives and
1653          * a status of 0 (no delivery yet attempted) or 3/4 (transient errors
1654          * were experienced and it's time to try again)
1655          */
1656         lines = num_tokens(instr, '\n');
1657         for (i=0; i<lines; ++i) {
1658                 extract_token(buf, instr, i, '\n', sizeof buf);
1659                 extract_token(key, buf, 0, '|', sizeof key);
1660                 extract_token(addr, buf, 1, '|', sizeof addr);
1661                 status = extract_int(buf, 2);
1662                 extract_token(dsn, buf, 3, '|', sizeof dsn);
1663                 if ( (!strcasecmp(key, "remote"))
1664                    && ((status==0)||(status==3)||(status==4)) ) {
1665
1666                         /* Remove this "remote" instruction from the set,
1667                          * but replace the set's final newline if
1668                          * remove_token() stripped it.  It has to be there.
1669                          */
1670                         remove_token(instr, i, '\n');
1671                         if (instr[strlen(instr)-1] != '\n') {
1672                                 strcat(instr, "\n");
1673                         }
1674
1675                         --i;
1676                         --lines;
1677                         CtdlLogPrintf(CTDL_DEBUG, "SMTP client: Trying <%s>\n", addr);
1678                         smtp_try(key, addr, &status, dsn, sizeof dsn, text_msgid, envelope_from);
1679                         if (status != 2) {
1680                                 if (results == NULL) {
1681                                         results = malloc(1024);
1682                                         memset(results, 0, 1024);
1683                                 }
1684                                 else {
1685                                         results = realloc(results, strlen(results) + 1024);
1686                                 }
1687                                 snprintf(&results[strlen(results)], 1024,
1688                                         "%s|%s|%d|%s\n",
1689                                         key, addr, status, dsn);
1690                         }
1691                 }
1692         }
1693
1694         if (results != NULL) {
1695                 instr = realloc(instr, strlen(instr) + strlen(results) + 2);
1696                 strcat(instr, results);
1697                 free(results);
1698         }
1699
1700
1701         /* Generate 'bounce' messages */
1702         smtp_do_bounce(instr);
1703
1704         /* Go through the delivery list, deleting completed deliveries */
1705         incomplete_deliveries_remaining =
1706                 smtp_purge_completed_deliveries(instr);
1707
1708
1709         /*
1710          * No delivery instructions remain, so delete both the instructions
1711          * message and the message message.
1712          */
1713         if (incomplete_deliveries_remaining <= 0) {
1714                 long delmsgs[2];
1715                 delmsgs[0] = msgnum;
1716                 delmsgs[1] = text_msgid;
1717                 CtdlDeleteMessages(SMTP_SPOOLOUT_ROOM, delmsgs, 2, "");
1718         }
1719
1720         /*
1721          * Uncompleted delivery instructions remain, so delete the old
1722          * instructions and replace with the updated ones.
1723          */
1724         if (incomplete_deliveries_remaining > 0) {
1725                 CtdlDeleteMessages(SMTP_SPOOLOUT_ROOM, &msgnum, 1, "");
1726                 msg = malloc(sizeof(struct CtdlMessage));
1727                 memset(msg, 0, sizeof(struct CtdlMessage));
1728                 msg->cm_magic = CTDLMESSAGE_MAGIC;
1729                 msg->cm_anon_type = MES_NORMAL;
1730                 msg->cm_format_type = FMT_RFC822;
1731                 msg->cm_fields['M'] = malloc(strlen(instr)+SIZ);
1732                 snprintf(msg->cm_fields['M'],
1733                         strlen(instr)+SIZ,
1734                         "Content-type: %s\n\n%s\n"
1735                         "attempted|%ld\n"
1736                         "retry|%ld\n",
1737                         SPOOLMIME, instr, (long)time(NULL), (long)retry );
1738                 CtdlSubmitMsg(msg, NULL, SMTP_SPOOLOUT_ROOM, QP_EADDR);
1739                 CtdlFreeMessage(msg);
1740         }
1741
1742         free(instr);
1743 }
1744
1745
1746
1747
1748 /*
1749  * smtp_queue_thread()
1750  *
1751  * Run through the queue sending out messages.
1752  */
1753 void *smtp_queue_thread(void *arg) {
1754         int num_processed = 0;
1755         struct CitContext smtp_queue_CC;
1756
1757         CtdlFillSystemContext(&smtp_queue_CC, "SMTP Send");
1758         citthread_setspecific(MyConKey, (void *)&smtp_queue_CC);
1759         CtdlLogPrintf(CTDL_DEBUG, "smtp_queue_thread() initializing\n");
1760
1761         while (!CtdlThreadCheckStop()) {
1762
1763                 CtdlLogPrintf(CTDL_INFO, "SMTP client: processing outbound queue\n");
1764
1765                 if (CtdlGetRoom(&CC->room, SMTP_SPOOLOUT_ROOM) != 0) {
1766                         CtdlLogPrintf(CTDL_ERR, "Cannot find room <%s>\n", SMTP_SPOOLOUT_ROOM);
1767                 }
1768                 else {
1769                         num_processed = CtdlForEachMessage(MSGS_ALL, 0L, NULL, SPOOLMIME, NULL, smtp_do_procmsg, NULL);
1770                 }
1771                 CtdlLogPrintf(CTDL_INFO, "SMTP client: queue run completed; %d messages processed\n", num_processed);
1772                 CtdlThreadSleep(60);
1773         }
1774
1775         CtdlClearSystemContext();
1776         return(NULL);
1777 }
1778
1779
1780
1781 /*****************************************************************************/
1782 /*                          SMTP UTILITY COMMANDS                            */
1783 /*****************************************************************************/
1784
1785 void cmd_smtp(char *argbuf) {
1786         char cmd[64];
1787         char node[256];
1788         char buf[1024];
1789         int i;
1790         int num_mxhosts;
1791
1792         if (CtdlAccessCheck(ac_aide)) return;
1793
1794         extract_token(cmd, argbuf, 0, '|', sizeof cmd);
1795
1796         if (!strcasecmp(cmd, "mx")) {
1797                 extract_token(node, argbuf, 1, '|', sizeof node);
1798                 num_mxhosts = getmx(buf, node);
1799                 cprintf("%d %d MX hosts listed for %s\n",
1800                         LISTING_FOLLOWS, num_mxhosts, node);
1801                 for (i=0; i<num_mxhosts; ++i) {
1802                         extract_token(node, buf, i, '|', sizeof node);
1803                         cprintf("%s\n", node);
1804                 }
1805                 cprintf("000\n");
1806                 return;
1807         }
1808
1809         else if (!strcasecmp(cmd, "runqueue")) {
1810                 run_queue_now = 1;
1811                 cprintf("%d All outbound SMTP will be retried now.\n", CIT_OK);
1812                 return;
1813         }
1814
1815         else {
1816                 cprintf("%d Invalid command.\n", ERROR + ILLEGAL_VALUE);
1817         }
1818
1819 }
1820
1821
1822 /*
1823  * Initialize the SMTP outbound queue
1824  */
1825 void smtp_init_spoolout(void) {
1826         struct ctdlroom qrbuf;
1827
1828         /*
1829          * Create the room.  This will silently fail if the room already
1830          * exists, and that's perfectly ok, because we want it to exist.
1831          */
1832         CtdlCreateRoom(SMTP_SPOOLOUT_ROOM, 3, "", 0, 1, 0, VIEW_MAILBOX);
1833
1834         /*
1835          * Make sure it's set to be a "system room" so it doesn't show up
1836          * in the <K>nown rooms list for Aides.
1837          */
1838         if (CtdlGetRoomLock(&qrbuf, SMTP_SPOOLOUT_ROOM) == 0) {
1839                 qrbuf.QRflags2 |= QR2_SYSTEM;
1840                 CtdlPutRoomLock(&qrbuf);
1841         }
1842 }
1843
1844
1845
1846
1847 /*****************************************************************************/
1848 /*                      MODULE INITIALIZATION STUFF                          */
1849 /*****************************************************************************/
1850 /*
1851  * This cleanup function blows away the temporary memory used by
1852  * the SMTP server.
1853  */
1854 void smtp_cleanup_function(void) {
1855
1856         /* Don't do this stuff if this is not an SMTP session! */
1857         if (CC->h_command_function != smtp_command_loop) return;
1858
1859         CtdlLogPrintf(CTDL_DEBUG, "Performing SMTP cleanup hook\n");
1860         free(SMTP);
1861 }
1862
1863
1864
1865 const char *CitadelServiceSMTP_MTA="SMTP-MTA";
1866 const char *CitadelServiceSMTPS_MTA="SMTPs-MTA";
1867 const char *CitadelServiceSMTP_MSA="SMTP-MSA";
1868 const char *CitadelServiceSMTP_LMTP="LMTP";
1869 const char *CitadelServiceSMTP_LMTP_UNF="LMTP-UnF";
1870
1871 CTDL_MODULE_INIT(smtp)
1872 {
1873         if (!threading)
1874         {
1875                 CtdlRegisterServiceHook(config.c_smtp_port,     /* SMTP MTA */
1876                                         NULL,
1877                                         smtp_mta_greeting,
1878                                         smtp_command_loop,
1879                                         NULL,
1880                                         CitadelServiceSMTP_MTA);
1881
1882 #ifdef HAVE_OPENSSL
1883                 CtdlRegisterServiceHook(config.c_smtps_port,
1884                                         NULL,
1885                                         smtps_greeting,
1886                                         smtp_command_loop,
1887                                         NULL,
1888                                         CitadelServiceSMTPS_MTA);
1889 #endif
1890
1891                 CtdlRegisterServiceHook(config.c_msa_port,      /* SMTP MSA */
1892                                         NULL,
1893                                         smtp_msa_greeting,
1894                                         smtp_command_loop,
1895                                         NULL,
1896                                         CitadelServiceSMTP_MSA);
1897
1898                 CtdlRegisterServiceHook(0,                      /* local LMTP */
1899                                         file_lmtp_socket,
1900                                         lmtp_greeting,
1901                                         smtp_command_loop,
1902                                         NULL,
1903                                         CitadelServiceSMTP_LMTP);
1904
1905                 CtdlRegisterServiceHook(0,                      /* local LMTP */
1906                                         file_lmtp_unfiltered_socket,
1907                                         lmtp_unfiltered_greeting,
1908                                         smtp_command_loop,
1909                                         NULL,
1910                                         CitadelServiceSMTP_LMTP_UNF);
1911
1912                 smtp_init_spoolout();
1913                 CtdlRegisterSessionHook(smtp_cleanup_function, EVT_STOP);
1914                 CtdlRegisterProtoHook(cmd_smtp, "SMTP", "SMTP utility commands");
1915                 CtdlThreadCreate("SMTP Send", CTDLTHREAD_BIGSTACK, smtp_queue_thread, NULL);
1916         }
1917
1918         /* return our Subversion id for the Log */
1919         return "smtp";
1920 }