libexec/dma/dma.c

   1 /*
   2  * Copyright (c) 2008 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Simon 'corecode' Schubert <corecode@fs.ei.tum.de>.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  * $DragonFly: src/libexec/dma/dma.c,v 1.5 2008/09/30 17:47:21 swildner Exp $
  35  */
  36
  37 #include <sys/ipc.h>
  38 #include <sys/param.h>
  39 #include <sys/queue.h>
  40 #include <sys/sem.h>
  41 #include <sys/socket.h>
  42 #include <sys/stat.h>
  43 #include <sys/types.h>
  44 #include <sys/wait.h>
  45
  46 #ifdef HAVE_CRYPTO
  47 #include <openssl/ssl.h>
  48 #endif /* HAVE_CRYPTO */
  49
  50 #include <dirent.h>
  51 #include <err.h>
  52 #include <errno.h>
  53 #include <fcntl.h>
  54 #include <grp.h>
  55 #include <inttypes.h>
  56 #include <netdb.h>
  57 #include <paths.h>
  58 #include <pwd.h>
  59 #include <signal.h>
  60 #include <stdarg.h>
  61 #include <stdio.h>
  62 #include <stdlib.h>
  63 #include <string.h>
  64 #include <syslog.h>
  65 #include <unistd.h>
  66
  67 #include "dma.h"
  68
  69
  70
  71 static void deliver(struct qitem *, int);
  72 static void deliver_smarthost(struct queue *, int);
  73 static int add_recp(struct queue *, const char *, const char *, int);
  74
  75 struct aliases aliases = LIST_HEAD_INITIALIZER(aliases);
  76 static struct strlist tmpfs = SLIST_HEAD_INITIALIZER(tmpfs);
  77 struct virtusers virtusers = LIST_HEAD_INITIALIZER(virtusers);
  78 struct authusers authusers = LIST_HEAD_INITIALIZER(authusers);
  79 static int daemonize = 1;
  80 struct config *config;
  81 int controlsocket_df, clientsocket_df, controlsocket_wl, clientsocket_wl, semkey;
  82
  83 static void
  84 release_children(void)
  85 {
  86         struct sembuf sema;
  87         int null = 0;
  88
  89         /*
  90          * Try to decrement semaphore as we start communicating with
  91          * write_to_local_user()
  92          */
  93         sema.sem_num = SEM_WL;
  94         sema.sem_op = -1;
  95         sema.sem_flg = 0;
  96         if (semop(semkey, &sema, 1) == -1) {
  97                 err(1, "semaphore decrement failed");
  98         }
  99
 100         /*
 101          * write_to_local_user() will exit and kill dotforwardhandler(), too
 102          * if the corresponding semaphore is zero
 103          * otherwise nothing happens
 104          */
 105         write(controlsocket_wl, &null, sizeof(null));
 106
 107         /*
 108          * Increment semaphore as we stop communicating with
 109          * write_to_local_user()
 110          */
 111         sema.sem_op = 1;
 112         if (semop(semkey, &sema, 1) == -1) {
 113                 err(1, "semaphore decrement failed");
 114         }
 115 }
 116
 117 char *
 118 hostname(void)
 119 {
 120         static char name[MAXHOSTNAMELEN+1];
 121
 122         if (gethostname(name, sizeof(name)) != 0)
 123                 strcpy(name, "(unknown hostname)");
 124
 125         return name;
 126 }
 127
 128 static char *
 129 set_from(const char *osender)
 130 {
 131         struct virtuser *v;
 132         char *sender;
 133
 134         if ((config->features & VIRTUAL) != 0) {
 135                 SLIST_FOREACH(v, &virtusers, next) {
 136                         if (strcmp(v->login, getlogin()) == 0) {
 137                                 sender = strdup(v->address);
 138                                 if (sender == NULL)
 139                                         return(NULL);
 140                                 goto out;
 141                         }
 142                 }
 143         }
 144
 145         if (osender) {
 146                 sender = strdup(osender);
 147                 if (sender == NULL)
 148                         return(NULL);
 149         } else {
 150                 if (asprintf(&sender, "%s@%s", getlogin(), hostname()) <= 0)
 151                         return(NULL);
 152         }
 153
 154         if (strchr(sender, '\n') != NULL) {
 155                 errno = EINVAL;
 156                 return(NULL);
 157         }
 158
 159 out:
 160         return(sender);
 161 }
 162
 163 static int
 164 read_aliases(void)
 165 {
 166         yyin = fopen(config->aliases, "r");
 167         if (yyin == NULL)
 168                 return(0);      /* not fatal */
 169         if (yyparse())
 170                 return(-1);     /* fatal error, probably malloc() */
 171         fclose(yyin);
 172         return(0);
 173 }
 174
 175 static int
 176 add_recp(struct queue *queue, const char *str, const char *sender, int expand)
 177 {
 178         struct qitem *it, *tit;
 179         struct stritem *sit;
 180         struct alias *al;
 181         struct passwd *pw;
 182         char *host;
 183         int aliased = 0;
 184
 185         it = calloc(1, sizeof(*it));
 186         if (it == NULL)
 187                 return(-1);
 188         it->addr = strdup(str);
 189         if (it->addr == NULL)
 190                 return(-1);
 191
 192         it->sender = sender;
 193         host = strrchr(it->addr, '@');
 194         if (host != NULL &&
 195             (strcmp(host + 1, hostname()) == 0 ||
 196              strcmp(host + 1, "localhost") == 0)) {
 197                 *host = 0;
 198         }
 199         LIST_FOREACH(tit, &queue->queue, next) {
 200                 /* weed out duplicate dests */
 201                 if (strcmp(tit->addr, it->addr) == 0) {
 202                         free(it->addr);
 203                         free(it);
 204                         return(0);
 205                 }
 206         }
 207         LIST_INSERT_HEAD(&queue->queue, it, next);
 208         if (strrchr(it->addr, '@') == NULL) {
 209                 /* local = 1 means its a username or mailbox */
 210                 it->local = 1;
 211                 /* only search for aliases and .forward if asked for */
 212                 /* needed to have the possibility to add an mailbox directly */
 213                 if (expand) {
 214                         /* first check /etc/aliases */
 215                         LIST_FOREACH(al, &aliases, next) {
 216                                 if (strcmp(al->alias, it->addr) != 0)
 217                                         continue;
 218                                 SLIST_FOREACH(sit, &al->dests, next) {
 219                                         if (add_recp(queue, sit->str,
 220                                             sender, 1) != 0)
 221                                                 return(-1);
 222                                 }
 223                                 aliased = 1;
 224                         }
 225                         if (aliased) {
 226                                 LIST_REMOVE(it, next);
 227                         } else {
 228                                 /* then check .forward of user */
 229                                 fd_set rfds;
 230                                 int ret;
 231                                 uint8_t len, type;
 232                                 struct sembuf sema;
 233                                 /* is the username valid */
 234                                 pw = getpwnam(it->addr);
 235                                 endpwent();
 236                                 if (pw == NULL)
 237                                         goto out;
 238
 239                                 /*
 240                                  * Try to decrement semaphore as we start
 241                                  * communicating with dotforwardhandler()
 242                                  */
 243                                 sema.sem_num = SEM_DF;
 244                                 sema.sem_op = -1;
 245                                 sema.sem_flg = 0;
 246                                 if (semop(semkey, &sema, 1) == -1) {
 247                                         err(1, "semaphore decrement failed");
 248                                 }
 249
 250                                 /* write username to dotforwardhandler */
 251                                 len = strlen(it->addr);
 252                                 write(controlsocket_df, &len, sizeof(len));
 253                                 write(controlsocket_df, it->addr, len);
 254                                 FD_ZERO(&rfds);
 255                                 FD_SET(controlsocket_df, &rfds);
 256
 257                                 /* wait for incoming redirects and pipes */
 258                                 while ((ret = select(controlsocket_df + 1,
 259                                     &rfds, NULL, NULL, NULL))) {
 260                                         /*
 261                                          * Receive back list of mailboxnames
 262                                          * and/or emailadresses
 263                                          */
 264                                         if (ret == -1) {
 265                                                 /*
 266                                                  * increment semaphore because
 267                                                  * we stopped communicating
 268                                                  * with dotforwardhandler()
 269                                                  */
 270                                                 sema.sem_op = 1;
 271                                                 semop(semkey, &sema, 1);
 272                                                 return(-1);
 273                                         }
 274                                         /* read type of .forward entry */
 275                                         read(controlsocket_df, &type, 1);
 276                                         if (type & ENDOFDOTFORWARD) {
 277                                                 /* end of .forward */
 278                                                 /*
 279                                                  * If there are redirects, then
 280                                                  * we do not need the original
 281                                                  * qitem any longer
 282                                                  */
 283                                                 if (aliased) {
 284                                                         LIST_REMOVE(it, next);
 285                                                 }
 286                                                 break;
 287                                         } else if (type & ISMAILBOX) {
 288                                                 /* redirect -> user/emailaddress */
 289                                                 /*
 290                                                  * FIXME shall there be the possibility to use
 291                                                  * usernames instead of mailboxes?
 292                                                  */
 293                                                 char *username;
 294                                                 read(controlsocket_df, &len, sizeof(len));
 295                                                 username = calloc(1, len + 1);
 296                                                 read(controlsocket_df, username, len);
 297                                                 /*
 298                                                  * Do not further expand since
 299                                                  * its remote or local mailbox
 300                                                  */
 301                                                 if (add_recp(queue, username, sender, 0) != 0) {
 302                                                         aliased = 1;
 303                                                 }
 304                                         } else if (type & ISPIPE) {
 305                                                 /* redirect to a pipe */
 306                                                 /*
 307                                                  * Create new qitem and save
 308                                                  * information in it
 309                                                  */
 310                                                 struct qitem *pit;
 311                                                 pit = calloc(1, sizeof(*pit));
 312                                                 if (pit == NULL) {
 313                                                         /*
 314                                                          * Increment semaphore
 315                                                          * because we stopped
 316                                                          * communicating with
 317                                                          * dotforwardhandler()
 318                                                          */
 319                                                         sema.sem_op = 1;
 320                                                         semop(semkey, &sema, 1);
 321                                                         return(-1);
 322                                                 }
 323                                                 LIST_INSERT_HEAD(&queue->queue, pit, next);
 324                                                 /*
 325                                                  * Save username to qitem,
 326                                                  * because its overwritten by
 327                                                  * pipe command
 328                                                  */
 329                                                 pit->pipeuser = strdup(it->addr);
 330                                                 pit->sender = sender;
 331                                                 /* local = 2 means redirect to pipe */
 332                                                 pit->local = 2;
 333                                                 read(controlsocket_df, &len, sizeof(len));
 334                                                 pit->addr = realloc(pit->addr, len + 1);
 335                                                 memset(pit->addr, 0, len + 1);
 336                                                 read(controlsocket_df, pit->addr, len);
 337                                                 aliased = 1;
 338                                         }
 339                                 }
 340                                 /*
 341                                  * Increment semaphore because we stopped
 342                                  * communicating with dotforwardhandler()
 343                                  */
 344                                 sema.sem_op = 1;
 345                                 semop(semkey, &sema, 1);
 346                         }
 347                 }
 348         } else {
 349                 it->local = 0;
 350         }
 351
 352         return(0);
 353
 354 out:
 355         free(it->addr);
 356         free(it);
 357         return(-1);
 358 }
 359
 360 static void
 361 deltmp(void)
 362 {
 363         struct stritem *t;
 364
 365         SLIST_FOREACH(t, &tmpfs, next) {
 366                 unlink(t->str);
 367         }
 368 }
 369
 370 static int
 371 gentempf(struct queue *queue)
 372 {
 373         char fn[PATH_MAX+1];
 374         struct stritem *t;
 375         int fd;
 376
 377         if (snprintf(fn, sizeof(fn), "%s/%s", config->spooldir, "tmp_XXXXXXXXXX") <= 0)
 378                 return(-1);
 379         fd = mkstemp(fn);
 380         if (fd < 0)
 381                 return(-1);
 382         queue->mailfd = fd;
 383
 384         queue->tmpf = strdup(fn);
 385         if (queue->tmpf == NULL) {
 386                 unlink(fn);
 387                 return(-1);
 388         }
 389         t = malloc(sizeof(*t));
 390         if (t != NULL) {
 391                 t->str = queue->tmpf;
 392                 SLIST_INSERT_HEAD(&tmpfs, t, next);
 393         }
 394         return(0);
 395 }
 396
 397 /*
 398  * spool file format:
 399  *
 400  * envelope-from
 401  * queue-id1 envelope-to1
 402  * queue-id2 envelope-to2
 403  * ...
 404  * <empty line>
 405  * mail data
 406  *
 407  * queue ids are unique, formed from the inode of the spool file
 408  * and a unique identifier.
 409  */
 410 static int
 411 preparespool(struct queue *queue, const char *sender)
 412 {
 413         char line[1000];        /* by RFC2822 */
 414         struct stat st;
 415         int error;
 416         struct qitem *it;
 417         FILE *queuef;
 418         off_t hdrlen;
 419
 420         error = snprintf(line, sizeof(line), "%s\n", sender);
 421         if (error < 0 || (size_t)error >= sizeof(line)) {
 422                 errno = E2BIG;
 423                 return(-1);
 424         }
 425         if (write(queue->mailfd, line, error) != error)
 426                 return(-1);
 427
 428         queuef = fdopen(queue->mailfd, "r+");
 429         if (queuef == NULL)
 430                 return(-1);
 431
 432         /*
 433          * Assign queue id to each dest.
 434          */
 435         if (fstat(queue->mailfd, &st) != 0)
 436                 return(-1);
 437         queue->id = st.st_ino;
 438         LIST_FOREACH(it, &queue->queue, next) {
 439                 if (asprintf(&it->queueid, "%"PRIxMAX".%"PRIxPTR,
 440                              queue->id, (uintptr_t)it) <= 0)
 441                         return(-1);
 442                 if (asprintf(&it->queuefn, "%s/%s",
 443                              config->spooldir, it->queueid) <= 0)
 444                         return(-1);
 445                 /* File may already exist */
 446                 if (stat(it->queuefn, &st) == 0) {
 447                         warn("Spoolfile already exists: %s", it->queuefn);
 448                         return(-1);
 449                 }
 450                 /* Reset errno to avoid confusion */
 451                 errno = 0;
 452                 it->queuef = queuef;
 453                 error = snprintf(line, sizeof(line), "%s %s\n",
 454                                it->queueid, it->addr);
 455                 if (error < 0 || (size_t)error >= sizeof(line))
 456                         return(-1);
 457                 if (write(queue->mailfd, line, error) != error)
 458                         return(-1);
 459         }
 460         line[0] = '\n';
 461         if (write(queue->mailfd, line, 1) != 1)
 462                 return(-1);
 463
 464         hdrlen = lseek(queue->mailfd, 0, SEEK_CUR);
 465         LIST_FOREACH(it, &queue->queue, next) {
 466                 it->hdrlen = hdrlen;
 467         }
 468         return(0);
 469 }
 470
 471 static char *
 472 rfc822date(void)
 473 {
 474         static char str[50];
 475         size_t error;
 476         time_t now;
 477
 478         now = time(NULL);
 479         error = strftime(str, sizeof(str), "%a, %d %b %Y %T %z",
 480                        localtime(&now));
 481         if (error == 0)
 482                 strcpy(str, "(date fail)");
 483         return(str);
 484 }
 485
 486 static int
 487 readmail(struct queue *queue, const char *sender, int nodot)
 488 {
 489         char line[1000];        /* by RFC2822 */
 490         size_t linelen;
 491         int error;
 492
 493         error = snprintf(line, sizeof(line), "\
 494 Received: from %s (uid %d)\n\
 495 \t(envelope-from %s)\n\
 496 \tid %"PRIxMAX"\n\
 497 \tby %s (%s)\n\
 498 \t%s\n",
 499                 getlogin(), getuid(),
 500                 sender,
 501                 queue->id,
 502                 hostname(), VERSION,
 503                 rfc822date());
 504         if (error < 0 || (size_t)error >= sizeof(line))
 505                 return(-1);
 506         if (write(queue->mailfd, line, error) != error)
 507                 return(-1);
 508
 509         while (!feof(stdin)) {
 510                 if (fgets(line, sizeof(line), stdin) == NULL)
 511                         break;
 512                 linelen = strlen(line);
 513                 if (linelen == 0 || line[linelen - 1] != '\n') {
 514                         errno = EINVAL;         /* XXX mark permanent errors */
 515                         return(-1);
 516                 }
 517                 if (!nodot && linelen == 2 && line[0] == '.')
 518                         break;
 519                 if ((size_t)write(queue->mailfd, line, linelen) != linelen)
 520                         return(-1);
 521         }
 522         if (fsync(queue->mailfd) != 0)
 523                 return(-1);
 524         return(0);
 525 }
 526
 527 static int
 528 linkspool(struct queue *queue)
 529 {
 530         struct qitem *it;
 531
 532         /*
 533          * Only if it is not a pipe delivery
 534          * pipe deliveries are only tried once so there
 535          * is no need for a spool-file, they use the
 536          * original tempfile
 537          */
 538
 539         LIST_FOREACH(it, &queue->queue, next) {
 540                 /*
 541                  * There shall be no files for pipe deliveries since not all
 542                  * information is saved in the header, so pipe delivery is
 543                  * tried once and forgotten thereafter.
 544                  */
 545                 if (it->local == 2)
 546                         continue;
 547                 if (link(queue->tmpf, it->queuefn) != 0)
 548                         goto delfiles;
 549         }
 550         return(0);
 551
 552 delfiles:
 553         LIST_FOREACH(it, &queue->queue, next) {
 554                 /*
 555                  * There are no files for pipe delivery, so they can't be
 556                  * deleted.
 557                  */
 558                 if (it->local == 2)
 559                         continue;
 560                 unlink(it->queuefn);
 561         }
 562         return(-1);
 563 }
 564
 565 static void
 566 go_background(struct queue *queue, int leavesemaphore)
 567 {
 568         struct sigaction sa;
 569         struct qitem *it;
 570         pid_t pid;
 571         int seen_remote_address = 0;
 572
 573         if (daemonize && daemon(0, 0) != 0) {
 574                 syslog(LOG_ERR, "[go_background] can not daemonize: %m");
 575                 exit(1);
 576         }
 577         daemonize = 0;
 578         bzero(&sa, sizeof(sa));
 579         sa.sa_flags = SA_NOCLDWAIT;
 580         sa.sa_handler = SIG_IGN;
 581         sigaction(SIGCHLD, &sa, NULL);
 582
 583
 584         LIST_FOREACH(it, &queue->queue, next) {
 585                 /*
 586                  * If smarthost is enabled, the address is remote
 587                  * set smarthost delivery flag, otherwise deliver it 'normal'.
 588                  */
 589                 if (config->smarthost != NULL && strlen(config->smarthost) > 0
 590                     && it->local == 0
 591                    ) {
 592                         seen_remote_address = 1;
 593                         /*
 594                          * if it is not the last entry, continue
 595                          * (if it is the last, start delivery in parent
 596                          */
 597                         if (LIST_NEXT(it, next) != NULL) {
 598                                 continue;
 599                         }
 600                 } else {
 601                         /*
 602                          * If item is local, we do not need it in the list any
 603                          * more, so delete it.
 604                          */
 605                         LIST_REMOVE(it, next);
 606                 }
 607                 pid = fork();
 608                 switch (pid) {
 609                 case -1:
 610                         syslog(LOG_ERR, "can not fork: %m");
 611                         exit(1);
 612                         break;
 613
 614                 case 0:
 615                         /*
 616                          * Child:
 617                          *
 618                          * return and deliver mail
 619                          */
 620
 621                         if (config->smarthost == NULL || strlen(config->smarthost) == 0 || it->local)
 622                                 if (LIST_NEXT(it, next) == NULL && !seen_remote_address)
 623                                         /* if there is no smarthost-delivery and we are the last item */
 624                                         deliver(it, leavesemaphore);
 625                                 else
 626                                         deliver(it, 0);
 627                         else
 628                                 _exit(0);
 629
 630                 default:
 631                         /*
 632                          * Parent:
 633                          *
 634                          * fork next child
 635                          */
 636                         /*
 637                          * If it is the last loop and there were remote
 638                          * addresses, start smarthost delivery.
 639                          * No need to doublecheck if smarthost is
 640                          * activated in config file.
 641                          */
 642                         if (LIST_NEXT(it, next) == NULL) {
 643                                 if (seen_remote_address) {
 644                                         deliver_smarthost(queue, leavesemaphore);
 645                                 } else {
 646                                         _exit(0);
 647                                 }
 648                         }
 649                         break;
 650                 }
 651         }
 652
 653         syslog(LOG_CRIT, "reached dead code");
 654         exit(1);
 655 }
 656
 657 static void
 658 bounce(struct qitem *it, const char *reason, int leavesemaphore)
 659 {
 660         struct queue bounceq;
 661         struct qitem *bit;
 662         char line[1000];
 663         int error;
 664         struct sembuf sema;
 665
 666         /* Don't bounce bounced mails */
 667         if (it->sender[0] == 0) {
 668                 /*
 669                  * If we are the last bounce, then decrement semaphore
 670                  * and release children.
 671                  */
 672                 if (leavesemaphore) {
 673                         /* semaphore-- (MUST NOT BLOCK BECAUSE ITS POSITIVE) */
 674                         sema.sem_num = SEM_SIGHUP;
 675                         sema.sem_op = -1;
 676                         sema.sem_flg = IPC_NOWAIT;
 677                         if (semop(semkey, &sema, 1) == -1) {
 678                                 err(1, "[deliver] semaphore decrement failed");
 679                         }
 680                         /* release child processes */
 681                         release_children();
 682                 }
 683                 syslog(LOG_CRIT, "%s: delivery panic: can't bounce a bounce",
 684                         it->queueid);
 685                 exit(1);
 686         }
 687
 688         syslog(LOG_ERR, "%s: delivery failed, bouncing",
 689                it->queueid);
 690
 691         LIST_INIT(&bounceq.queue);
 692         if (add_recp(&bounceq, it->sender, "", 1) != 0)
 693                 goto fail;
 694         if (gentempf(&bounceq) != 0)
 695                 goto fail;
 696         if (preparespool(&bounceq, "") != 0)
 697                 goto fail;
 698
 699         bit = LIST_FIRST(&bounceq.queue);
 700         error = fprintf(bit->queuef, "\
 701 Received: from MAILER-DAEMON\n\
 702 \tid %"PRIxMAX"\n\
 703 \tby %s (%s)\n\
 704 \t%s\n\
 705 X-Original-To: <%s>\n\
 706 From: MAILER-DAEMON <>\n\
 707 To: %s\n\
 708 Subject: Mail delivery failed\n\
 709 Message-Id: <%"PRIxMAX"@%s>\n\
 710 Date: %s\n\
 711 \n\
 712 This is the %s at %s.\n\
 713 \n\
 714 There was an error delivering your mail to <%s>.\n\
 715 \n\
 716 %s\n\
 717 \n\
 718 Message headers follow.\n\
 719 \n\
 720 ",
 721                 bounceq.id,
 722                 hostname(), VERSION,
 723                 rfc822date(),
 724                 it->addr,
 725                 it->sender,
 726                 bounceq.id, hostname(),
 727                 rfc822date(),
 728                 VERSION, hostname(),
 729                 it->addr,
 730                 reason);
 731         if (error < 0)
 732                 goto fail;
 733         if (fflush(bit->queuef) != 0)
 734                 goto fail;
 735
 736         if (fseek(it->queuef, it->hdrlen, SEEK_SET) != 0)
 737                 goto fail;
 738         while (!feof(it->queuef)) {
 739                 if (fgets(line, sizeof(line), it->queuef) == NULL)
 740                         break;
 741                 if (line[0] == '\n')
 742                         break;
 743                 write(bounceq.mailfd, line, strlen(line));
 744         }
 745         if (fsync(bounceq.mailfd) != 0)
 746                 goto fail;
 747         if (linkspool(&bounceq) != 0)
 748                 goto fail;
 749         /* bounce is safe */
 750
 751         unlink(it->queuefn);
 752         fclose(it->queuef);
 753
 754         go_background(&bounceq, leavesemaphore);
 755         /* NOTREACHED */
 756
 757 fail:
 758         /*
 759          * If we are the last bounce, then decrement semaphore
 760          * and release children.
 761          */
 762         if (leavesemaphore) {
 763                 /* semaphore-- (MUST NOT BLOCK BECAUSE ITS POSITIVE) */
 764                 sema.sem_num = SEM_SIGHUP;
 765                 sema.sem_op = -1;
 766                 sema.sem_flg = IPC_NOWAIT;
 767                 if (semop(semkey, &sema, 1) == -1) {
 768                         err(1, "[deliver] semaphore decrement failed");
 769                 }
 770                 /* release child processes */
 771                 release_children();
 772         }
 773         syslog(LOG_CRIT, "%s: error creating bounce: %m", it->queueid);
 774         unlink(it->queuefn);
 775         exit(1);
 776 }
 777
 778 static int
 779 deliver_local(struct qitem *it, const char **errmsg)
 780 {
 781         char line[1000];
 782         char fn[PATH_MAX+1];
 783         int len;
 784         uint8_t mode = 0, fail = 0;
 785         ssize_t linelen;
 786         time_t now = time(NULL);
 787         char *username = NULL;
 788         struct sembuf sema;
 789
 790
 791         /*
 792          * Try to decrement semaphore as we start communicating with
 793          * write_to_local_user()
 794          */
 795         sema.sem_num = SEM_WL;
 796         sema.sem_op = -1;
 797         sema.sem_flg = 0;
 798         if (semop(semkey, &sema, 1) == -1) {
 799                 err(1, "semaphore decrement failed");
 800         }
 801
 802
 803         /* Tell write_to_local_user() the username to drop the privileges */
 804         if (it->local == 1) { /* mailbox delivery */
 805                 username = it->addr;
 806         } else if (it->local == 2) { /* pipe delivery */
 807                 username = it->pipeuser;
 808         }
 809         len = strlen(username);
 810         write(controlsocket_wl, &len, sizeof(len));
 811         write(controlsocket_wl, username, len);
 812         read(controlsocket_wl, &fail, sizeof(fail));
 813         if (fail) {
 814                 syslog(LOG_ERR,
 815                         "%s: local delivery deferred: can not fork and drop privileges `%s': %m",
 816                         it->queueid, username);
 817                 /*
 818                  * Increment semaphore because we stopped communicating with
 819                  * write_to_local_user().
 820                  */
 821                 sema.sem_op = 1;
 822                 semop(semkey, &sema, 1);
 823                 return(1);
 824         }
 825
 826
 827         /* Tell write_to_local_user() the delivery mode (write to mailbox || pipe) */
 828         if (it->local == 1) { /* mailbox delivery */
 829                 mode = ISMAILBOX;
 830                 len = snprintf(fn, sizeof(fn), "%s/%s", _PATH_MAILDIR, it->addr);
 831                 if (len < 0 || (size_t)len >= sizeof(fn)) {
 832                         syslog(LOG_ERR, "%s: local delivery deferred: %m",
 833                                         it->queueid);
 834                         /*
 835                          * Increment semaphore because we stopped communicating
 836                          * with write_to_local_user().
 837                          */
 838                         sema.sem_op = 1;
 839                         semop(semkey, &sema, 1);
 840                         return(1);
 841                 }
 842         } else if (it->local == 2) { /* pipe delivery */
 843                 mode = ISPIPE;
 844                 strncpy(fn, it->addr, sizeof(fn));
 845                 len = strlen(fn);
 846         }
 847         write(controlsocket_wl, &len, sizeof(len));
 848         write(controlsocket_wl, fn, len);
 849         write(controlsocket_wl, &mode, sizeof(mode));
 850         read(controlsocket_wl, &fail, sizeof(fail));
 851         if (fail) {
 852                 errno = fail;
 853                 syslog(LOG_ERR,
 854                         "%s: local delivery deferred: can not (p)open `%s': %m",
 855                         it->queueid, it->addr);
 856                 /*
 857                  * Increment semaphore because we stopped communicating
 858                  * with write_to_local_user().
 859                  */
 860                 sema.sem_op = 1;
 861                 semop(semkey, &sema, 1);
 862                 return(1);
 863         }
 864
 865
 866         /* Prepare transfer of mail-data */
 867         if (fseek(it->queuef, it->hdrlen, SEEK_SET) != 0) {
 868                 syslog(LOG_ERR, "%s: local delivery deferred: can not seek: %m",
 869                        it->queueid);
 870                 /*
 871                  * Increment semaphore because we stopped communicating
 872                  * with write_to_local_user().
 873                  */
 874                 sema.sem_op = 1;
 875                 semop(semkey, &sema, 1);
 876                 return(1);
 877         }
 878
 879
 880         /* Send first header line. */
 881         linelen = snprintf(line, sizeof(line), "From %s\t%s", it->sender, ctime(&now));
 882         if (linelen < 0 || (size_t)linelen >= sizeof(line)) {
 883                 syslog(LOG_ERR, "%s: local delivery deferred: can not write header: %m",
 884                        it->queueid);
 885                 /*
 886                  * Increment semaphore because we stopped communicating
 887                  * with write_to_local_user().
 888                  */
 889                 sema.sem_op = 1;
 890                 semop(semkey, &sema, 1);
 891                 return(1);
 892         }
 893
 894         write(controlsocket_wl, &linelen, sizeof(linelen));
 895         write(controlsocket_wl, line, linelen);
 896
 897         read(controlsocket_wl, &fail, sizeof(fail));
 898         if (fail) {
 899                 goto wrerror;
 900         }
 901
 902
 903         /* Read mail data and transfer it to write_to_local_user(). */
 904         while (!feof(it->queuef)) {
 905                 if (fgets(line, sizeof(line), it->queuef) == NULL)
 906                         break;
 907                 linelen = strlen(line);
 908                 if (linelen == 0 || line[linelen - 1] != '\n') {
 909                         syslog(LOG_CRIT,
 910                                 "%s: local delivery failed: corrupted queue file",
 911                                 it->queueid);
 912                         *errmsg = "corrupted queue file";
 913                         len = -1;
 914                         /* break receive and write loop at write_to_local_user() */
 915                         linelen = 0;
 916                         write(controlsocket_wl, &linelen, sizeof(linelen));
 917                         /* and send error state */
 918                         linelen = 1;
 919                         write(controlsocket_wl, &linelen, sizeof(linelen));
 920                         goto chop;
 921                 }
 922
 923                 if (strncmp(line, "From ", 5) == 0) {
 924                         const char *gt = ">";
 925                         size_t sizeofchar = 1;
 926
 927                         write(controlsocket_wl, &sizeofchar, sizeof(sizeofchar));
 928                         write(controlsocket_wl, gt, 1);
 929                         read(controlsocket_wl, &fail, sizeof(fail));
 930                         if (fail) {
 931                                 goto wrerror;
 932                         }
 933                 }
 934                 write(controlsocket_wl, &linelen, sizeof(linelen));
 935                 write(controlsocket_wl, line, linelen);
 936                 read(controlsocket_wl, &fail, sizeof(fail));
 937                 if (fail) {
 938                         goto wrerror;
 939                 }
 940         }
 941
 942         /* Send final linebreak */
 943         line[0] = '\n';
 944         linelen = 1;
 945         write(controlsocket_wl, &linelen, sizeof(linelen));
 946         write(controlsocket_wl, line, linelen);
 947         read(controlsocket_wl, &fail, sizeof(fail));
 948         if (fail) {
 949                 goto wrerror;
 950         }
 951
 952
 953         /* break receive and write loop in write_to_local_user() */
 954         linelen = 0;
 955         /* send '0' twice, because above we send '0' '1' in case of error */
 956         write(controlsocket_wl, &linelen, sizeof(linelen));
 957         write(controlsocket_wl, &linelen, sizeof(linelen));
 958         read(controlsocket_wl, &fail, sizeof(fail));
 959         if (fail) {
 960                 goto wrerror;
 961         }
 962
 963
 964         /*
 965          * Increment semaphore because we stopped communicating
 966          * with write_to_local_user().
 967          */
 968         sema.sem_op = 1;
 969         semop(semkey, &sema, 1);
 970         return(0);
 971
 972 wrerror:
 973         errno = fail;
 974         syslog(LOG_ERR, "%s: local delivery failed: write error: %m",
 975                it->queueid);
 976         len = 1;
 977 chop:
 978         read(controlsocket_wl, &fail, sizeof(fail));
 979         if (fail == 2) {
 980                 syslog(LOG_WARNING, "%s: error recovering mbox `%s': %m",
 981                         it->queueid, fn);
 982         }
 983         /*
 984          * Increment semaphore because we stopped communicating
 985          * with write_to_local_user().
 986          */
 987         sema.sem_op = 1;
 988         semop(semkey, &sema, 1);
 989         return(len);
 990 }
 991
 992 static void
 993 deliver(struct qitem *it, int leavesemaphore)
 994 {
 995         int error;
 996         unsigned int backoff = MIN_RETRY;
 997         const char *errmsg = "unknown bounce reason";
 998         struct timeval now;
 999         struct stat st;
1000         struct sembuf sema;
1001
1002         if (it->local == 2) {
1003                 syslog(LOG_INFO, "%s: mail from=<%s> to=<%s> command=<%s>",
1004                                 it->queueid, it->sender, it->pipeuser, it->addr);
1005         } else {
1006                 syslog(LOG_INFO, "%s: mail from=<%s> to=<%s>",
1007                                 it->queueid, it->sender, it->addr);
1008         }
1009
1010 retry:
1011         syslog(LOG_INFO, "%s: trying delivery",
1012                it->queueid);
1013
1014         /*
1015          * Only increment semaphore, if we are not the last bounce
1016          * because there is still a incremented semaphore from
1017          * the bounced delivery
1018          */
1019         if (!leavesemaphore) {
1020                 /*
1021                  * Increment semaphore for each mail we try to deliver.
1022                  * When completing the transmit, the semaphore is decremented.
1023                  * If the semaphore is zero the other childs know that they
1024                  * can terminate.
1025                  */
1026                 sema.sem_num = SEM_SIGHUP;
1027                 sema.sem_op = 1;
1028                 sema.sem_flg = 0;
1029                 if (semop(semkey, &sema, 1) == -1) {
1030                         err(1, "[deliver] semaphore increment failed");
1031                 }
1032         }
1033         if (it->local) {
1034                 error = deliver_local(it, &errmsg);
1035         } else {
1036                 error = deliver_remote(it, &errmsg, NULL);
1037         }
1038
1039         switch (error) {
1040         case 0:
1041                 /* semaphore-- (MUST NOT BLOCK BECAUSE ITS POSITIVE) */
1042                 sema.sem_num = SEM_SIGHUP;
1043                 sema.sem_op = -1;
1044                 sema.sem_flg = IPC_NOWAIT;
1045                 if (semop(semkey, &sema, 1) == -1) {
1046                         err(1, "[deliver] semaphore decrement failed");
1047                 }
1048                 /* release child processes */
1049                 release_children();
1050                 /* Do not try to delete the spool file: pipe mode */
1051                 if (it->local != 2)
1052                         unlink(it->queuefn);
1053                 syslog(LOG_INFO, "%s: delivery successful",
1054                        it->queueid);
1055                 exit(0);
1056
1057         case 1:
1058                 /* pipe delivery only tries once, then gives up */
1059                 if (it->local == 2) {
1060                         /* decrement-- (MUST NOT BLOCK BECAUSE ITS POSITIVE) */
1061                         sema.sem_num = SEM_SIGHUP;
1062                         sema.sem_op = -1;
1063                         sema.sem_flg = IPC_NOWAIT;
1064                         if (semop(semkey, &sema, 1) == -1) {
1065                                 err(1, "[deliver] semaphore decrement failed");
1066                         }
1067                         /* release child processes */
1068                         release_children();
1069                         syslog(LOG_ERR, "%s: delivery to pipe `%s' failed, giving up",
1070                                it->queueid, it->addr);
1071                         exit(1);
1072                 }
1073                 if (stat(it->queuefn, &st) != 0) {
1074                         /* semaphore-- (MUST NOT BLOCK BECAUSE ITS POSITIVE) */
1075                         sema.sem_num = SEM_SIGHUP;
1076                         sema.sem_op = -1;
1077                         sema.sem_flg = IPC_NOWAIT;
1078                         if (semop(semkey, &sema, 1) == -1) {
1079                                 err(1, "[deliver] semaphore decrement failed");
1080                         }
1081                         /* release child processes */
1082                         release_children();
1083                         syslog(LOG_ERR, "%s: lost queue file `%s'",
1084                                it->queueid, it->queuefn);
1085                         exit(1);
1086                 }
1087                 if (gettimeofday(&now, NULL) == 0 &&
1088                     (now.tv_sec - st.st_mtimespec.tv_sec > MAX_TIMEOUT)) {
1089                         char *msg;
1090
1091                         if (asprintf(&msg,
1092                             "Could not deliver for the last %d seconds. Giving up.",
1093                             MAX_TIMEOUT) > 0)
1094                                 errmsg = msg;
1095                         goto bounce;
1096                 }
1097                 sleep(backoff);
1098                 backoff *= 2;
1099                 if (backoff > MAX_RETRY)
1100                         backoff = MAX_RETRY;
1101                 goto retry;
1102
1103         case -1:
1104         default:
1105                 break;
1106         }
1107
1108 bounce:
1109         bounce(it, errmsg, 1);
1110         /* NOTREACHED */
1111 }
1112
1113 /*
1114  * deliver_smarthost() is similar to deliver(), but has some differences:
1115  * -deliver_smarthost() works with a queue
1116  * -each entry in this queue has a corresponding file in the spooldir
1117  * -if the mail is sent correctly to a address, delete the corresponding file,
1118  *      even if there were errors with other addresses
1119  * -so deliver_remote must tell deliver_smarthost to which addresses it has
1120  *  successfully sent the mail
1121  *  -this can be done with 3 queues:
1122  *   -one queue for sent mails
1123  *   -one queue for 4xx addresses (tempfail)
1124  *   -one queue for 5xx addresses (permfail)
1125  *  -the sent mails are deleted
1126  *  -the 4xx are tried again
1127  *  -the 5xx are bounced
1128  */
1129
1130 static void
1131 deliver_smarthost(struct queue *queue, int leavesemaphore)
1132 {
1133         int error, bounces = 0;
1134         unsigned int backoff = MIN_RETRY;
1135         const char *errmsg = "unknown bounce reason";
1136         struct timeval now;
1137         struct stat st;
1138         struct sembuf sema;
1139         struct qitem *it, *tit;
1140         struct queue *queues[4], *bouncequeue, successqueue, tempfailqueue,
1141                 permfailqueue;
1142
1143         /*
1144          * only increment semaphore, if we are not the last bounce
1145          * because there is still a incremented semaphore from
1146          * the bounced delivery
1147          */
1148         if (!leavesemaphore) {
1149                 /*
1150                  * Increment semaphore for each mail we try to deliver.
1151                  * When completing the transmit, the semaphore is decremented.
1152                  * If the semaphore is zero the other childs know that they
1153                  * can terminate.
1154                  */
1155                 sema.sem_num = SEM_SIGHUP;
1156                 sema.sem_op = 1;
1157                 sema.sem_flg = 0;
1158                 if (semop(semkey, &sema, 1) == -1) {
1159                         err(1, "[deliver] semaphore increment failed");
1160                 }
1161         }
1162
1163         queues[0] = queue;
1164         queues[1] = &successqueue;
1165         queues[2] = &tempfailqueue;
1166         queues[3] = &permfailqueue;
1167
1168 retry:
1169         /* initialise 3 empty queues and link it in queues[] */
1170         LIST_INIT(&queues[1]->queue); /* successful sent items */
1171         LIST_INIT(&queues[2]->queue); /* temporary error items */
1172         LIST_INIT(&queues[3]->queue); /* permanent error items */
1173
1174         it = LIST_FIRST(&queues[0]->queue);
1175
1176         syslog(LOG_INFO, "%s: trying delivery",
1177                it->queueid);
1178
1179         /* if queuefile of first qitem is gone, the mail can't be sended out */
1180         if (stat(it->queuefn, &st) != 0) {
1181                         syslog(LOG_ERR, "%s: lost queue file `%s'",
1182                                it->queueid, it->queuefn);
1183                         /* semaphore-- (MUST NOT BLOCK BECAUSE ITS POSITIVE) */
1184                         sema.sem_num = SEM_SIGHUP;
1185                         sema.sem_op = -1;
1186                         sema.sem_flg = IPC_NOWAIT;
1187                         if (semop(semkey, &sema, 1) == -1) {
1188                                 err(1, "[deliver] semaphore decrement failed");
1189                         }
1190                         release_children();
1191                         exit(1);
1192         }
1193
1194         error = deliver_remote(it, &errmsg, queues);
1195
1196         /* if there was an error, do nothing with the other 3 queues! */
1197         if (error == 0) {
1198
1199                 /*
1200                  * If there are permanent errors, bounce items in permanent
1201                  * error queue.
1202                  */
1203                 if (!LIST_EMPTY(&queues[3]->queue)) {
1204                         bounces = 1;
1205                         pid_t pid;
1206                         pid = fork();
1207                         switch (pid) {
1208                                 case -1:
1209                                         syslog(LOG_ERR, "can not fork: %m");
1210                                         exit(1);
1211                                         break;
1212
1213                                 case 0:
1214                                         /*
1215                                          * Child:
1216                                          *
1217                                          * Tell which queue to bounce and set
1218                                          * errmsg.  Child will exit as soon as
1219                                          * all childs for bounces are spawned.
1220                                          * So no need to set up a signal handler.
1221                                          */
1222                                         bouncequeue = queues[3];
1223                                         errmsg = "smarthost sent permanent error (5xx)";
1224                                         goto bounce;
1225
1226                                 default:
1227                                         /*
1228                                          * Parent:
1229                                          *
1230                                          * continue with stuff
1231                                          */
1232                                         break;
1233                         }
1234                 }
1235
1236                 /* delete successfully sent items */
1237                 if (!LIST_EMPTY(&queues[1]->queue)) {
1238                         LIST_FOREACH(tit, &queues[1]->queue, next) {
1239                                 unlink(tit->queuefn);
1240                                 LIST_REMOVE(tit, next);
1241                                 syslog(LOG_INFO, "%s: delivery successful",
1242                                                 tit->queueid);
1243                         }
1244                 }
1245         }
1246
1247         /* If the temporary error queue is empty and there was no error, finish */
1248         if (LIST_EMPTY(&queues[2]->queue) && error == 0) {
1249                 /* only decrement semaphore if there were no bounces! */
1250                 if (!bounces) {
1251                         /* semaphore-- (MUST NOT BLOCK BECAUSE ITS POSITIVE) */
1252                         sema.sem_num = SEM_SIGHUP;
1253                         sema.sem_op = -1;
1254                         sema.sem_flg = IPC_NOWAIT;
1255                         if (semop(semkey, &sema, 1) == -1) {
1256                                 err(1, "[deliver] semaphore decrement failed");
1257                         }
1258                         /* release child processes */
1259                         release_children();
1260                 }
1261                 exit(0);
1262
1263                 /* if there are remaining items, set up retry timer */
1264         } else {
1265
1266                 /*
1267                  * if there was an error, do not touch queues[0]!
1268                  * and try to deliver all items again
1269                  */
1270
1271                 if (!error) {
1272                         /* wipe out old queue */
1273                         if (!LIST_EMPTY(&queues[0]->queue)) {
1274                                 LIST_FOREACH(tit, &queues[0]->queue, next) {
1275                                         unlink(tit->queuefn);
1276                                         LIST_REMOVE(tit, next);
1277                                 }
1278                                 LIST_INIT(&queues[0]->queue);
1279                         }
1280                         /* link temporary error queue to queues[0] */
1281                         queues[0] = &tempfailqueue;
1282                         /* and link queues[2] to wiped out queue */
1283                         queues[2] = queue;
1284                 }
1285
1286                 if (gettimeofday(&now, NULL) == 0 &&
1287                     (now.tv_sec - st.st_mtimespec.tv_sec > MAX_TIMEOUT)) {
1288                         char *msg;
1289
1290                         if (asprintf(&msg,
1291                                 "Could not deliver for the last %d seconds. Giving up.",
1292                                 MAX_TIMEOUT) > 0) {
1293                                 errmsg = msg;
1294                         }
1295                         /* bounce remaining items which have temporary errors */
1296                         bouncequeue = queues[2];
1297                         goto bounce;
1298                 }
1299                 sleep(backoff);
1300                 backoff *= 2;
1301                 if (backoff > MAX_RETRY)
1302                         backoff = MAX_RETRY;
1303                 goto retry;
1304         }
1305
1306 bounce:
1307         LIST_FOREACH(tit, &bouncequeue->queue, next) {
1308                 struct sigaction sa;
1309                 pid_t pid;
1310                 bzero(&sa, sizeof(sa));
1311                 sa.sa_flags = SA_NOCLDWAIT;
1312                 sa.sa_handler = SIG_IGN;
1313                 sigaction(SIGCHLD, &sa, NULL);
1314
1315                 /* fork is needed, because bounce() does not return */
1316                 pid = fork();
1317                 switch (pid) {
1318                         case -1:
1319                                 syslog(LOG_ERR, "can not fork: %m");
1320                                 exit(1);
1321                                 break;
1322
1323                         case 0:
1324                                 /*
1325                                  * Child:
1326                                  *
1327                                  * bounce mail
1328                                  */
1329
1330                                 LIST_REMOVE(tit, next);
1331                                 if (LIST_NEXT(tit, next) == NULL) {
1332                                         /*
1333                                          * For the last bounce, do not increment
1334                                          * the semaphore when delivering the
1335                                          * bounce.
1336                                          */
1337                                         bounce(tit, errmsg, 1);
1338                                 } else {
1339                                         bounce(tit, errmsg, 0);
1340                                 }
1341                                 /* NOTREACHED */
1342
1343                         default:
1344                                 /*
1345                                  * Parent:
1346                                  */
1347                                 break;
1348                 }
1349
1350         }
1351         /* last parent shall exit, too */
1352         _exit(0);
1353         /* NOTREACHED */
1354 }
1355
1356 static void
1357 load_queue(struct queue *queue)
1358 {
1359         struct stat st;
1360         struct qitem *it;
1361         //struct queue queue, itmqueue;
1362         struct queue itmqueue;
1363         DIR *spooldir;
1364         struct dirent *de;
1365         char line[1000];
1366         char *fn;
1367         FILE *queuef;
1368         char *sender;
1369         char *addr;
1370         char *queueid;
1371         char *queuefn;
1372         off_t hdrlen;
1373         int fd;
1374
1375         LIST_INIT(&queue->queue);
1376
1377         spooldir = opendir(config->spooldir);
1378         if (spooldir == NULL)
1379                 err(1, "reading queue");
1380
1381         while ((de = readdir(spooldir)) != NULL) {
1382                 sender = NULL;
1383                 queuef = NULL;
1384                 queueid = NULL;
1385                 queuefn = NULL;
1386                 fn = NULL;
1387                 LIST_INIT(&itmqueue.queue);
1388
1389                 /* ignore temp files */
1390                 if (strncmp(de->d_name, "tmp_", 4) == 0 ||
1391                     de->d_type != DT_REG)
1392                         continue;
1393                 if (asprintf(&queuefn, "%s/%s", config->spooldir, de->d_name) < 0)
1394                         goto fail;
1395                 fd = open(queuefn, O_RDONLY|O_EXLOCK|O_NONBLOCK);
1396                 if (fd < 0) {
1397                         /* Ignore locked files */
1398                         if (errno == EWOULDBLOCK)
1399                                 continue;
1400                         goto skip_item;
1401                 }
1402
1403                 queuef = fdopen(fd, "r");
1404                 if (queuef == NULL)
1405                         goto skip_item;
1406                 if (fgets(line, sizeof(line), queuef) == NULL ||
1407                     line[0] == 0)
1408                         goto skip_item;
1409                 line[strlen(line) - 1] = 0;     /* chop newline */
1410                 sender = strdup(line);
1411                 if (sender == NULL)
1412                         goto skip_item;
1413
1414                 for (;;) {
1415                         if (fgets(line, sizeof(line), queuef) == NULL ||
1416                             line[0] == 0)
1417                                 goto skip_item;
1418                         if (line[0] == '\n')
1419                                 break;
1420                         line[strlen(line) - 1] = 0;
1421                         queueid = strdup(line);
1422                         if (queueid == NULL)
1423                                 goto skip_item;
1424                         addr = strchr(queueid, ' ');
1425                         if (addr == NULL)
1426                                 goto skip_item;
1427                         *addr++ = 0;
1428                         if (fn != NULL)
1429                                 free(fn);
1430                         if (asprintf(&fn, "%s/%s", config->spooldir, queueid) < 0)
1431                                 goto skip_item;
1432                         /* Item has already been delivered? */
1433                         if (stat(fn, &st) != 0)
1434                                 continue;
1435                         if (add_recp(&itmqueue, addr, sender, 0) != 0)
1436                                 goto skip_item;
1437                         it = LIST_FIRST(&itmqueue.queue);
1438                         it->queuef = queuef;
1439                         it->queueid = queueid;
1440                         it->queuefn = fn;
1441                         fn = NULL;
1442                 }
1443                 if (LIST_EMPTY(&itmqueue.queue)) {
1444                         warnx("queue file without items: `%s'", queuefn);
1445                         goto skip_item2;
1446                 }
1447                 hdrlen = ftell(queuef);
1448                 while ((it = LIST_FIRST(&itmqueue.queue)) != NULL) {
1449                         it->hdrlen = hdrlen;
1450                         LIST_REMOVE(it, next);
1451                         LIST_INSERT_HEAD(&queue->queue, it, next);
1452                 }
1453                 continue;
1454
1455 skip_item:
1456                 warn("reading queue: `%s'", queuefn);
1457 skip_item2:
1458                 if (sender != NULL)
1459                         free(sender);
1460                 if (queuefn != NULL)
1461                         free(queuefn);
1462                 if (fn != NULL)
1463                         free(fn);
1464                 if (queueid != NULL)
1465                         free(queueid);
1466                 close(fd);
1467         }
1468         closedir(spooldir);
1469         return;
1470
1471 fail:
1472         err(1, "reading queue");
1473 }
1474
1475 static void
1476 run_queue(struct queue *queue)
1477 {
1478         if (LIST_EMPTY(&queue->queue))
1479                 return;
1480
1481         go_background(queue, 0);
1482         /* NOTREACHED */
1483 }
1484
1485 static void
1486 show_queue(struct queue *queue)
1487 {
1488         struct qitem *it;
1489
1490         if (LIST_EMPTY(&queue->queue)) {
1491                 printf("Mail queue is empty\n");
1492                 return;
1493         }
1494
1495         LIST_FOREACH(it, &queue->queue, next) {
1496                 printf("\
1497 ID\t: %s\n\
1498 From\t: %s\n\
1499 To\t: %s\n--\n", it->queueid, it->sender, it->addr);
1500         }
1501 }
1502
1503 /*
1504  * TODO:
1505  *
1506  * - alias processing
1507  * - use group permissions
1508  * - proper sysexit codes
1509  */
1510
1511 static int
1512 parseandexecute(int argc, char **argv)
1513 {
1514         char *sender = NULL;
1515         char tag[255];
1516         struct queue queue;
1517         struct queue lqueue;
1518         int i, ch;
1519         int nodot = 0, doqueue = 0, showq = 0;
1520
1521         atexit(deltmp);
1522         LIST_INIT(&queue.queue);
1523         snprintf(tag, 254, "dma");
1524
1525         opterr = 0;
1526         while ((ch = getopt(argc, argv, "A:b:Df:iL:o:O:q:r:")) != -1) {
1527                 switch (ch) {
1528                 case 'A':
1529                         /* -AX is being ignored, except for -A{c,m} */
1530                         if (optarg[0] == 'c' || optarg[0] == 'm') {
1531                                 break;
1532                         }
1533                         /* else FALLTRHOUGH */
1534                 case 'b':
1535                         /* -bX is being ignored, except for -bp */
1536                         if (optarg[0] == 'p') {
1537                                 showq = 1;
1538                                 break;
1539                         }
1540                         /* else FALLTRHOUGH */
1541                 case 'D':
1542                         daemonize = 0;
1543                         break;
1544                 case 'L':
1545                         if (optarg != NULL)
1546                                 snprintf(tag, 254, "%s", optarg);
1547                         break;
1548                 case 'f':
1549                 case 'r':
1550                         sender = optarg;
1551                         break;
1552
1553                 case 'o':
1554                         /* -oX is being ignored, except for -oi */
1555                         if (optarg[0] != 'i')
1556                                 break;
1557                         /* else FALLTRHOUGH */
1558                 case 'O':
1559                         break;
1560                 case 'i':
1561                         nodot = 1;
1562                         break;
1563
1564                 case 'q':
1565                         doqueue = 1;
1566                         break;
1567
1568                 default:
1569                         release_children();
1570                         exit(1);
1571                 }
1572         }
1573         argc -= optind;
1574         argv += optind;
1575         opterr = 1;
1576
1577         openlog(tag, LOG_PID | LOG_PERROR, LOG_MAIL);
1578
1579         config = malloc(sizeof(struct config));
1580         if (config == NULL)
1581                 errx(1, "Cannot allocate enough memory");
1582
1583         memset(config, 0, sizeof(struct config));
1584         if (parse_conf(CONF_PATH, config) < 0) {
1585                 free(config);
1586                 release_children();
1587                 errx(1, "reading config file");
1588         }
1589
1590         if (config->features & VIRTUAL)
1591                 if (parse_virtuser(config->virtualpath) < 0) {
1592                         release_children();
1593                         errx(1, "error reading virtual user file: %s",
1594                                 config->virtualpath);
1595                 }
1596
1597         if (parse_authfile(config->authpath) < 0) {
1598                 release_children();
1599                 err(1, "reading SMTP authentication file");
1600         }
1601
1602         if (showq) {
1603                 if (argc != 0)
1604                         errx(1, "sending mail and displaying queue is"
1605                                 " mutually exclusive");
1606                 load_queue(&lqueue);
1607                 show_queue(&lqueue);
1608                 return(0);
1609         }
1610
1611         if (doqueue) {
1612                 if (argc != 0)
1613                         errx(1, "sending mail and queue pickup is mutually exclusive");
1614                 load_queue(&lqueue);
1615                 run_queue(&lqueue);
1616                 return(0);
1617         }
1618
1619         if (read_aliases() != 0) {
1620                 release_children();
1621                 err(1, "reading aliases");
1622         }
1623
1624         if ((sender = set_from(sender)) == NULL) {
1625                 release_children();
1626                 err(1, "setting from address");
1627         }
1628
1629         if (gentempf(&queue) != 0) {
1630                 release_children();
1631                 err(1, "create temp file");
1632         }
1633
1634         for (i = 0; i < argc; i++) {
1635                 if (add_recp(&queue, argv[i], sender, 1) != 0) {
1636                         release_children();
1637                         errx(1, "invalid recipient `%s'\n", argv[i]);
1638                 }
1639         }
1640
1641         if (LIST_EMPTY(&queue.queue)) {
1642                 release_children();
1643                 errx(1, "no recipients");
1644         }
1645
1646         if (preparespool(&queue, sender) != 0) {
1647                 release_children();
1648                 err(1, "creating spools (1)");
1649         }
1650
1651         if (readmail(&queue, sender, nodot) != 0) {
1652                 release_children();
1653                 err(1, "reading mail");
1654         }
1655
1656         if (linkspool(&queue) != 0) {
1657                 release_children();
1658                 err(1, "creating spools (2)");
1659         }
1660
1661         /* From here on the mail is safe. */
1662
1663         if (config->features & DEFER)
1664                 return(0);
1665
1666         go_background(&queue, 0);
1667
1668         /* NOTREACHED */
1669
1670         return(0);
1671 }
1672
1673 /*
1674  * dotforwardhandler() waits for incoming username
1675  * for each username, the .forward file is read and parsed
1676  * earch entry is given back to add_recp which communicates
1677  * with dotforwardhandler()
1678  */
1679 static int
1680 dotforwardhandler(void)
1681 {
1682         pid_t pid;
1683         fd_set rfds;
1684         int ret;
1685         uint8_t stmt, namelength;
1686
1687         FD_ZERO(&rfds);
1688         FD_SET(clientsocket_df, &rfds);
1689
1690         /* wait for incoming usernames */
1691         ret = select(clientsocket_df + 1, &rfds, NULL, NULL, NULL);
1692         if (ret == -1) {
1693                 return(-1);
1694         }
1695         while (read(clientsocket_df, &namelength, sizeof(namelength))) {
1696                 char *username;
1697                 struct passwd *userentry;
1698                 if (namelength == 0) {
1699                         /* there will be no more usernames, we can terminate */
1700                         break;
1701                 }
1702                 /* read username and get homedir */
1703                 username = calloc(1, namelength + 1);
1704                 read(clientsocket_df, username, namelength);
1705                 userentry = getpwnam(username);
1706                 endpwent();
1707
1708                 pid = fork();
1709                 if (pid == 0) { /* child */
1710                         FILE *forward;
1711                         char *dotforward;
1712                         /* drop privileges to user */
1713                         if (chdir("/"))
1714                                 return(-1);
1715                         if (initgroups(username, userentry->pw_gid))
1716                                 return(-1);
1717                         if (setgid(userentry->pw_gid))
1718                                 return(-1);
1719                         if (setuid(userentry->pw_uid))
1720                                 return(-1);
1721
1722                         /* read ~/.forward */
1723                         dotforward = strdup(userentry->pw_dir);
1724                         forward = fopen(strcat(dotforward, "/.forward"), "r");
1725                         if (forward == NULL) { /* no dotforward */
1726                                 stmt = ENDOFDOTFORWARD;
1727                                 write(clientsocket_df, &stmt, 1);
1728                                 continue;
1729                         }
1730
1731
1732                         /* parse ~/.forward */
1733                         while (!feof(forward)) { /* each line in ~/.forward */
1734                                 char *target = NULL;
1735                                 /* 255 Bytes should be enough for a pipe and a emailaddress */
1736                                 uint8_t len;
1737                                 char line[2048];
1738                                 memset(line, 0, 2048);
1739                                 fgets(line, sizeof(line), forward);
1740                                 /* FIXME allow comments? */
1741                                 if (((target = strtok(line, "\t\n")) != NULL) &&
1742                                     (strncmp(target, "|", 1) == 0)) {
1743                                         /* if first char is a '|', the line is a pipe */
1744                                         stmt = ISPIPE;
1745                                         write(clientsocket_df, &stmt, 1);
1746                                         len = strlen(target);
1747                                         /* remove the '|' */
1748                                         len--;
1749                                         /* send result back to add_recp */
1750                                         write(clientsocket_df, &len, sizeof(len));
1751                                         write(clientsocket_df, target + 1, len);
1752                                 } else {
1753                                         /* if first char is not a '|', the line is a mailbox */
1754                                         stmt = ISMAILBOX;
1755                                         write(clientsocket_df, &stmt, 1);
1756                                         len = strlen(target);
1757                                         /* send result back to add_recp */
1758                                         write(clientsocket_df, &len, sizeof(len));
1759                                         write(clientsocket_df, target, len);
1760                                 }
1761                         }
1762                         stmt = ENDOFDOTFORWARD;
1763                         /* send end of .forward to add_recp */
1764                         write(clientsocket_df, &stmt, 1);
1765                         _exit(0);
1766                 } else if (pid < 0) { /* fork failed */
1767                         return(1);
1768                 } else { /* parent */
1769                         /* parent waits while child is processing .forward */
1770                         waitpid(-1, NULL, 0);
1771                 }
1772         }
1773         return(0);
1774 }
1775
1776 /*
1777  * write_to_local_user() writes to a mailbox or
1778  * to a pipe in a user context and communicates with deliver_local()
1779  */
1780 static int
1781 write_to_local_user(void)
1782 {
1783         pid_t pid;
1784         int length;
1785         size_t linelen;
1786
1787         /* wait for incoming targets */
1788         while (read(clientsocket_wl, &length, sizeof(length))) {
1789                 char *target;
1790                 uint8_t mode, fail = 0;
1791                 char line[1000];
1792                 int mbox = 0;
1793                 off_t mboxlen = 0;
1794                 FILE *mypipe = NULL;
1795                 struct passwd *userentry;
1796
1797                 target = calloc(1, length + 1);
1798                 if (length == 0) {
1799                         struct sembuf sema;
1800                         int retval;
1801                         /* check if semaphore is '0' */
1802                         sema.sem_num = SEM_SIGHUP;
1803                         sema.sem_op = 0;
1804                         sema.sem_flg = IPC_NOWAIT;
1805                         retval = semop(semkey, &sema, 1);
1806                         if (retval == 0 || errno == EINVAL) {
1807                                 /*
1808                                  * if semaphore is '0' then the last mail is sent
1809                                  * and there is no need for a write_to_local_user()
1810                                  * so we can exit
1811                                  *
1812                                  * if errno is EINVAL, then someone has removed the semaphore, so we shall exit, too
1813                                  */
1814                                 break;
1815                         } else {
1816                                 continue;
1817                         }
1818                 }
1819                 /* read username and get uid/gid */
1820                 read(clientsocket_wl, target, length);
1821
1822                 userentry = getpwnam(target);
1823                 endpwent();
1824
1825                 pid = fork();
1826                 if (pid == 0) { /* child */
1827                         /* drop privileges to user and tell if there is something wrong */
1828                         if (chdir("/")) {
1829                                 fail = errno;
1830                                 write(clientsocket_wl, &fail, sizeof(fail));
1831                                 fail = 0;
1832                                 write(clientsocket_wl, &fail, sizeof(fail));
1833                                 free(target);
1834                                 _exit(1);
1835                         }
1836                         if (initgroups(target, userentry->pw_gid)) {
1837                                 fail = errno;
1838                                 write(clientsocket_wl, &fail, sizeof(fail));
1839                                 fail = 0;
1840                                 write(clientsocket_wl, &fail, sizeof(fail));
1841                                 free(target);
1842                                 _exit(1);
1843                         }
1844                         if (setgid(userentry->pw_gid)) {
1845                                 fail = errno;
1846                                 write(clientsocket_wl, &fail, sizeof(fail));
1847                                 fail = 0;
1848                                 write(clientsocket_wl, &fail, sizeof(fail));
1849                                 free(target);
1850                                 _exit(1);
1851                         }
1852                         if (setuid(userentry->pw_uid)) {
1853                                 fail = errno;
1854                                 write(clientsocket_wl, &fail, sizeof(fail));
1855                                 fail = 0;
1856                                 write(clientsocket_wl, &fail, sizeof(fail));
1857                                 free(target);
1858                                 _exit(1);
1859                         }
1860                         /* and go on with execution outside of if () */
1861                 } else if (pid < 0) { /* fork failed */
1862                         fail = errno;
1863                         write(clientsocket_wl, &fail, sizeof(fail));
1864                         fail = 0;
1865                         write(clientsocket_wl, &fail, sizeof(fail));
1866                         free(target);
1867                         _exit(1);
1868                 } else { /* parent */
1869                         struct sembuf sema;
1870                         int retval;
1871                         /* wait for child to finish and continue loop */
1872                         waitpid(-1, NULL, 0);
1873                         /* check if semaphore is '0' */
1874                         sema.sem_num = SEM_SIGHUP;
1875                         sema.sem_op = 0;
1876                         sema.sem_flg = IPC_NOWAIT;
1877                         retval = semop(semkey, &sema, 1);
1878                         if (retval == 0 || errno == EINVAL) {
1879                                 /*
1880                                  * if semaphore is '0' then the last mail is sent
1881                                  * and there is no need for a write_to_local_user()
1882                                  * so we can exit
1883                                  *
1884                                  * if errno is EINVAL, then someone has removed the semaphore, so we shall exit, too
1885                                  */
1886                                 break;
1887                         } else if (errno != EAGAIN) {
1888                                 err(1, "[write_to_local_user] semop_op = 0 failed");
1889                         }
1890                         continue;
1891                 }
1892                 /* child code again here */
1893                 /* send ack, we are ready to go on with mode and target */
1894                 write(clientsocket_wl, &fail, sizeof(fail));
1895
1896                 read(clientsocket_wl, &length, sizeof(length));
1897                 target = realloc(target, length + 1);
1898                 memset(target, 0, length + 1);
1899                 read(clientsocket_wl, target, length);
1900                 read(clientsocket_wl, &mode, sizeof(mode));
1901                 if (mode & ISMAILBOX) {
1902                         /* if mode is mailbox, open mailbox */
1903                         /* mailx removes users mailspool file if empty, so open with O_CREAT */
1904                         mbox = open(target, O_WRONLY | O_EXLOCK | O_APPEND | O_CREAT, S_IRUSR | S_IWUSR);
1905                         if (mbox < 0) {
1906                                 fail = errno;
1907                                 write(clientsocket_wl, &fail, sizeof(fail));
1908                                 fail = 0;
1909                                 write(clientsocket_wl, &fail, sizeof(fail));
1910                                 _exit(1);
1911                         }
1912                         mboxlen = lseek(mbox, 0, SEEK_CUR);
1913                 } else if (mode & ISPIPE) {
1914                         /* if mode is mailbox, popen pipe */
1915                         fflush(NULL);
1916                         if ((mypipe = popen(target, "w")) == NULL) {
1917                                 fail = errno;
1918                                 write(clientsocket_wl, &fail, sizeof(fail));
1919                                 fail = 0;
1920                                 write(clientsocket_wl, &fail, sizeof(fail));
1921                                 _exit(1);
1922                         }
1923                 }
1924                 /* send ack, we are ready to receive mail contents */
1925                 write(clientsocket_wl, &fail, sizeof(fail));
1926
1927                 /* write to file/pipe loop */
1928                 while (read(clientsocket_wl, &linelen, sizeof(linelen))) {
1929                         if (linelen == 0) {
1930                                 read(clientsocket_wl, &linelen, sizeof(linelen));
1931                                 if (linelen == 0) {
1932                                         break;
1933                                 } else {
1934                                         /* if linelen != 0, then there is a error on sender side */
1935                                         goto chop;
1936                                 }
1937                         }
1938                         /* receive line */
1939                         read(clientsocket_wl, line, linelen);
1940
1941                         /* write line to target */
1942                         if (mode & ISMAILBOX) { /* mailbox delivery */
1943                                 if ((size_t)write(mbox, line, linelen) != linelen) {
1944                                         goto failure;
1945                                 }
1946                         } else if (mode & ISPIPE) { /* pipe delivery */
1947                                 if (fwrite(line, 1, linelen, mypipe) != linelen) {
1948                                         goto failure;
1949                                 }
1950                         }
1951                         /* send ack */
1952                         write(clientsocket_wl, &fail, sizeof(fail));
1953                 }
1954
1955                 /* close target after succesfully written last line */
1956                 if (mode & ISMAILBOX) { /* mailbox delivery */
1957                         close(mbox);
1958                 } else if (mode & ISPIPE) { /* pipe delivery */
1959                         pclose(mypipe);
1960                 }
1961                 /* send ack and exit */
1962                 write(clientsocket_wl, &fail, sizeof(fail));
1963                 _exit(0);
1964 failure:
1965                 fail = errno;
1966                 write(clientsocket_wl, &fail, sizeof(fail));
1967 chop:
1968                 fail = 0;
1969                 /* reset mailbox if there was something wrong */
1970                 if (mode & ISMAILBOX && ftruncate(mbox, mboxlen) != 0) {
1971                         fail = 2;
1972                 }
1973                 write(clientsocket_wl, &fail, sizeof(fail));
1974                 if (mode & ISMAILBOX) { /* mailbox delivery */
1975                         close(mbox);
1976                 } else if (mode & ISPIPE) { /* pipe delivery */
1977                         pclose(mypipe);
1978                 }
1979                 _exit(1);
1980         }
1981         uint8_t null = 0;
1982         /* release dotforwardhandler out of loop */
1983         write(controlsocket_df, &null, sizeof(null));
1984         /* we do not need the semaphores any more */
1985         semctl(semkey, 0, IPC_RMID, 0);
1986         _exit(0);
1987 }
1988
1989 int
1990 main(int argc, char **argv)
1991 {
1992         pid_t pid;
1993         int sockets1[2], sockets2[2];
1994         struct sembuf sema;
1995         struct ipc_perm semperm;
1996
1997         if (geteuid() != 0) {
1998                 fprintf(stderr, "This executable must be set setuid root!\n");
1999                 return(-1);
2000         }
2001
2002         /* create socketpair for dotforwardhandler() communication */
2003         if (socketpair(PF_UNIX, SOCK_STREAM, 0, sockets1) != 0) {
2004                 err(1,"Socketpair1 creation failed!\n");
2005         }
2006         /* df is short for DotForwardhandler */
2007         controlsocket_df = sockets1[0];
2008         clientsocket_df = sockets1[1];
2009
2010         /* create socketpair for write_to_local_user() communication */
2011         if (socketpair(PF_UNIX, SOCK_STREAM, 0, sockets2) != 0) {
2012                 err(1,"Socketpair2 creation failed!\n");
2013         }
2014         /* wl is short for Write_to_Local_user */
2015         controlsocket_wl = sockets2[0];
2016         clientsocket_wl = sockets2[1];
2017
2018         /*
2019          * create semaphores:
2020          *      -one for exclusive dotforwardhandler communication
2021          *      -one for exclusive write_to_local_user communication
2022          *      -another for signaling that the queue is completely processed
2023          */
2024         semkey = semget(IPC_PRIVATE, 3, IPC_CREAT | IPC_EXCL | 0660);
2025         if (semkey == -1) {
2026                 err(1,"[main] Creating semaphores failed");
2027         }
2028
2029         /* adjust privileges of semaphores */
2030         struct passwd *pw;
2031         if ((pw = getpwnam("nobody")) == NULL)
2032                 err(1, "Can't get uid of user 'nobody'");
2033         endpwent();
2034
2035         struct group *grp;
2036         if ((grp = getgrnam("mail")) == NULL)
2037                 err(1, "Can't get gid of group 'mail'");
2038         endgrent();
2039
2040         semperm.uid = pw->pw_uid;
2041         semperm.gid = grp->gr_gid;
2042         semperm.mode = 0660;
2043         if (semctl(semkey, SEM_DF, IPC_SET, &semperm) == -1) {
2044                 err(1, "[main] semctl(SEM_DF)");
2045         }
2046         if (semctl(semkey, SEM_WL, IPC_SET, &semperm) == -1) {
2047                 err(1, "[main] semctl(SEM_WL)");
2048         }
2049         if (semctl(semkey, SEM_SIGHUP, IPC_SET, &semperm) == -1) {
2050                 err(1, "[main] semctl(SEM_SIGHUP)");
2051         }
2052
2053         sema.sem_num = SEM_DF;
2054         sema.sem_op = 1;
2055         sema.sem_flg = 0;
2056         if (semop(semkey, &sema, 1) == -1) {
2057                 err(1, "[main] increment semaphore SEM_DF");
2058         }
2059
2060         sema.sem_num = SEM_WL;
2061         sema.sem_op = 1;
2062         sema.sem_flg = 0;
2063         if (semop(semkey, &sema, 1) == -1) {
2064                 err(1, "[main] increment semaphore SEM_WL");
2065         }
2066
2067         pid = fork();
2068         if (pid == 0) { /* part _WITH_ root privileges */
2069                 /* fork another process which goes into background */
2070                 if (daemonize && daemon(0, 0) != 0) {
2071                         syslog(LOG_ERR, "[main] can not daemonize: %m");
2072                         exit(1);
2073                 }
2074                 pid = fork();
2075                 /* both processes are running simultaneousily */
2076                 if (pid == 0) { /* child */
2077                         /* this process handles .forward read requests */
2078                         dotforwardhandler();
2079                         _exit(0);
2080                 } else if (pid < 0) {
2081                         err(1, "[main] Fork failed!\n");
2082                         return(-1);
2083                 } else { /* parent */
2084                         /* this process writes to mailboxes if needed */
2085                         write_to_local_user();
2086                         _exit(0);
2087                 }
2088         } else if (pid < 0) {
2089                 err(1, "Fork failed!\n");
2090                 return(-1);
2091         } else { /* part _WITHOUT_ root privileges */
2092                 /* drop privileges */
2093                 /* FIXME to user mail? */
2094                 chdir("/");
2095                 if (initgroups("nobody", pw->pw_gid) != 0)
2096                         err(1, "initgroups");
2097 #if 0
2098                 if (setgid(grp->gr_gid) != 0) /* set to group 'mail' */
2099 #else
2100                 /* FIXME */
2101                 if (setgid(6) != 0) /* set to group 'mail' */
2102 #endif
2103                         err(1, "setgid");
2104                 if (setuid(pw->pw_uid) != 0) /* set to user 'nobody' */
2105                         err(1, "setuid");
2106
2107                 /* parse command line and execute main mua code */
2108                 parseandexecute(argc, argv);
2109
2110                 /* release child processes */
2111                 release_children();
2112         }
2113
2114         return(0);
2115 }
2116