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
  35 #include <sys/param.h>
  36 #include <sys/queue.h>
  37 #include <sys/stat.h>
  38 #include <sys/types.h>
  39 #include <sys/wait.h>
  40
  41 #include <dirent.h>
  42 #include <err.h>
  43 #include <errno.h>
  44 #include <fcntl.h>
  45 #include <inttypes.h>
  46 #include <paths.h>
  47 #include <pwd.h>
  48 #include <signal.h>
  49 #include <stdarg.h>
  50 #include <stdio.h>
  51 #include <stdlib.h>
  52 #include <string.h>
  53 #include <syslog.h>
  54 #include <unistd.h>
  55
  56 #include "dma.h"
  57
  58
  59 static void deliver(struct qitem *);
  60
  61 struct aliases aliases = LIST_HEAD_INITIALIZER(aliases);
  62 struct strlist tmpfs = SLIST_HEAD_INITIALIZER(tmpfs);
  63 struct virtusers virtusers = LIST_HEAD_INITIALIZER(virtusers);
  64 struct authusers authusers = LIST_HEAD_INITIALIZER(authusers);
  65 const char *username;
  66 const char *logident_base;
  67
  68 static int daemonize = 1;
  69
  70 struct config config = {
  71         .smarthost      = NULL,
  72         .port           = 25,
  73         .aliases        = "/var/mail/aliases",
  74         .spooldir       = "/var/spool/dma",
  75         .virtualpath    = NULL,
  76         .authpath       = NULL,
  77         .certfile       = NULL,
  78         .features       = 0,
  79         .mailname       = NULL,
  80         .mailnamefile   = NULL,
  81 };
  82
  83
  84 static char *
  85 set_from(struct queue *queue, const char *osender)
  86 {
  87         struct virtuser *v;
  88         char *sender;
  89
  90         if ((config.features & VIRTUAL) != 0) {
  91                 SLIST_FOREACH(v, &virtusers, next) {
  92                         if (strcmp(v->login, username) == 0) {
  93                                 sender = strdup(v->address);
  94                                 if (sender == NULL)
  95                                         return(NULL);
  96                                 goto out;
  97                         }
  98                 }
  99         }
 100
 101         if (osender) {
 102                 sender = strdup(osender);
 103                 if (sender == NULL)
 104                         return (NULL);
 105         } else {
 106                 if (asprintf(&sender, "%s@%s", username, hostname()) <= 0)
 107                         return (NULL);
 108         }
 109
 110         if (strchr(sender, '\n') != NULL) {
 111                 errno = EINVAL;
 112                 return (NULL);
 113         }
 114
 115 out:
 116         queue->sender = sender;
 117         return (sender);
 118 }
 119
 120 static int
 121 read_aliases(void)
 122 {
 123         yyin = fopen(config.aliases, "r");
 124         if (yyin == NULL) {
 125                 /*
 126                  * Non-existing aliases file is not a fatal error
 127                  */
 128                 if (errno == ENOENT)
 129                         return (0);
 130                 /* Other problems are. */
 131                 return (-1);
 132         }
 133         if (yyparse())
 134                 return (-1);    /* fatal error, probably malloc() */
 135         fclose(yyin);
 136         return (0);
 137 }
 138
 139 int
 140 add_recp(struct queue *queue, const char *str, int expand)
 141 {
 142         struct qitem *it, *tit;
 143         struct stritem *sit;
 144         struct alias *al;
 145         struct passwd *pw;
 146         char *host;
 147         int aliased = 0;
 148
 149         it = calloc(1, sizeof(*it));
 150         if (it == NULL)
 151                 return (-1);
 152         it->addr = strdup(str);
 153         if (it->addr == NULL)
 154                 return (-1);
 155
 156         it->sender = queue->sender;
 157         host = strrchr(it->addr, '@');
 158         if (host != NULL &&
 159             (strcmp(host + 1, hostname()) == 0 ||
 160              strcmp(host + 1, "localhost") == 0)) {
 161                 *host = 0;
 162         }
 163         LIST_FOREACH(tit, &queue->queue, next) {
 164                 /* weed out duplicate dests */
 165                 if (strcmp(tit->addr, it->addr) == 0) {
 166                         free(it->addr);
 167                         free(it);
 168                         return (0);
 169                 }
 170         }
 171         LIST_INSERT_HEAD(&queue->queue, it, next);
 172         if (strrchr(it->addr, '@') == NULL) {
 173                 it->remote = 0;
 174                 if (expand) {
 175                         LIST_FOREACH(al, &aliases, next) {
 176                                 if (strcmp(al->alias, it->addr) != 0)
 177                                         continue;
 178                                 SLIST_FOREACH(sit, &al->dests, next) {
 179                                         if (add_recp(queue, sit->str, 1) != 0)
 180                                                 return (-1);
 181                                 }
 182                                 aliased = 1;
 183                         }
 184                         if (aliased) {
 185                                 LIST_REMOVE(it, next);
 186                         } else {
 187                                 /* Local destination, check */
 188                                 pw = getpwnam(it->addr);
 189                                 if (pw == NULL)
 190                                         goto out;
 191                                 /* XXX read .forward */
 192                                 endpwent();
 193                         }
 194                 }
 195         } else {
 196                 it->remote = 1;
 197         }
 198
 199         return (0);
 200
 201 out:
 202         free(it->addr);
 203         free(it);
 204         return (-1);
 205 }
 206
 207 static struct qitem *
 208 go_background(struct queue *queue)
 209 {
 210         struct sigaction sa;
 211         struct qitem *it;
 212         pid_t pid;
 213
 214         if (daemonize && daemon(0, 0) != 0) {
 215                 syslog(LOG_ERR, "can not daemonize: %m");
 216                 exit(1);
 217         }
 218         daemonize = 0;
 219
 220         bzero(&sa, sizeof(sa));
 221         sa.sa_flags = SA_NOCLDWAIT;
 222         sa.sa_handler = SIG_IGN;
 223         sigaction(SIGCHLD, &sa, NULL);
 224
 225         LIST_FOREACH(it, &queue->queue, next) {
 226                 /* No need to fork for the last dest */
 227                 if (LIST_NEXT(it, next) == NULL)
 228                         goto retit;
 229
 230                 pid = fork();
 231                 switch (pid) {
 232                 case -1:
 233                         syslog(LOG_ERR, "can not fork: %m");
 234                         exit(1);
 235                         break;
 236
 237                 case 0:
 238                         /*
 239                          * Child:
 240                          *
 241                          * return and deliver mail
 242                          */
 243 retit:
 244                         /*
 245                          * If necessary, acquire the queue and * mail files.
 246                          * If this fails, we probably were raced by another
 247                          * process.
 248                          */
 249                         setlogident("%s", it->queueid);
 250                         if (acquirespool(it) < 0)
 251                                 exit(1);
 252                         dropspool(queue, it);
 253                         return (it);
 254
 255                 default:
 256                         /*
 257                          * Parent:
 258                          *
 259                          * fork next child
 260                          */
 261                         break;
 262                 }
 263         }
 264
 265         syslog(LOG_CRIT, "reached dead code");
 266         exit(1);
 267 }
 268
 269 static void
 270 deliver(struct qitem *it)
 271 {
 272         int error;
 273         unsigned int backoff = MIN_RETRY;
 274         const char *errmsg = "unknown bounce reason";
 275         struct timeval now;
 276         struct stat st;
 277
 278 retry:
 279         syslog(LOG_INFO, "trying delivery");
 280
 281         if (it->remote)
 282                 error = deliver_remote(it, &errmsg);
 283         else
 284                 error = deliver_local(it, &errmsg);
 285
 286         switch (error) {
 287         case 0:
 288                 delqueue(it);
 289                 syslog(LOG_INFO, "delivery successful");
 290                 exit(0);
 291
 292         case 1:
 293                 if (stat(it->queuefn, &st) != 0) {
 294                         syslog(LOG_ERR, "lost queue file `%s'", it->queuefn);
 295                         exit(1);
 296                 }
 297                 if (gettimeofday(&now, NULL) == 0 &&
 298                     (now.tv_sec - st.st_mtimespec.tv_sec > MAX_TIMEOUT)) {
 299                         asprintf(__DECONST(void *, &errmsg),
 300                                  "Could not deliver for the last %d seconds. Giving up.",
 301                                  MAX_TIMEOUT);
 302                         goto bounce;
 303                 }
 304                 sleep(backoff);
 305                 backoff *= 2;
 306                 if (backoff > MAX_RETRY)
 307                         backoff = MAX_RETRY;
 308                 goto retry;
 309
 310         case -1:
 311         default:
 312                 break;
 313         }
 314
 315 bounce:
 316         bounce(it, errmsg);
 317         /* NOTREACHED */
 318 }
 319
 320 void
 321 run_queue(struct queue *queue)
 322 {
 323         struct qitem *it;
 324
 325         if (LIST_EMPTY(&queue->queue))
 326                 return;
 327
 328         it = go_background(queue);
 329         deliver(it);
 330         /* NOTREACHED */
 331 }
 332
 333 static void
 334 show_queue(struct queue *queue)
 335 {
 336         struct qitem *it;
 337         int locked = 0; /* XXX */
 338
 339         if (LIST_EMPTY(&queue->queue)) {
 340                 printf("Mail queue is empty\n");
 341                 return;
 342         }
 343
 344         LIST_FOREACH(it, &queue->queue, next) {
 345                 printf("ID\t: %s%s\n"
 346                        "From\t: %s\n"
 347                        "To\t: %s\n",
 348                        it->queueid,
 349                        locked ? "*" : "",
 350                        it->sender, it->addr);
 351
 352                 if (LIST_NEXT(it, next) != NULL)
 353                         printf("--\n");
 354         }
 355 }
 356
 357 /*
 358  * TODO:
 359  *
 360  * - alias processing
 361  * - use group permissions
 362  * - proper sysexit codes
 363  */
 364
 365 int
 366 main(int argc, char **argv)
 367 {
 368         char *sender = NULL;
 369         struct queue queue;
 370         int i, ch;
 371         int nodot = 0, doqueue = 0, showq = 0, queue_only = 0;
 372         int recp_from_header = 0;
 373
 374         atexit(deltmp);
 375
 376         bzero(&queue, sizeof(queue));
 377         LIST_INIT(&queue.queue);
 378
 379         if (strcmp(argv[0], "mailq") == 0) {
 380                 argv++; argc--;
 381                 showq = 1;
 382                 if (argc != 0)
 383                         errx(1, "invalid arguments");
 384                 goto skipopts;
 385         }
 386
 387         opterr = 0;
 388         while ((ch = getopt(argc, argv, ":A:b:B:C:d:Df:F:h:iL:N:no:O:q:r:R:tUV:vX:")) != -1) {
 389                 switch (ch) {
 390                 case 'A':
 391                         /* -AX is being ignored, except for -A{c,m} */
 392                         if (optarg[0] == 'c' || optarg[0] == 'm') {
 393                                 break;
 394                         }
 395                         /* else FALLTRHOUGH */
 396                 case 'b':
 397                         /* -bX is being ignored, except for -bp */
 398                         if (optarg[0] == 'p') {
 399                                 showq = 1;
 400                                 break;
 401                         } else if (optarg[0] == 'q') {
 402                                 queue_only = 1;
 403                                 break;
 404                         }
 405                         /* else FALLTRHOUGH */
 406                 case 'D':
 407                         daemonize = 0;
 408                         break;
 409                 case 'L':
 410                         logident_base = optarg;
 411                         break;
 412                 case 'f':
 413                 case 'r':
 414                         sender = optarg;
 415                         break;
 416
 417                 case 't':
 418                         recp_from_header = 1;
 419                         break;
 420
 421                 case 'o':
 422                         /* -oX is being ignored, except for -oi */
 423                         if (optarg[0] != 'i')
 424                                 break;
 425                         /* else FALLTRHOUGH */
 426                 case 'O':
 427                         break;
 428                 case 'i':
 429                         nodot = 1;
 430                         break;
 431
 432                 case 'q':
 433                         doqueue = 1;
 434                         break;
 435
 436                 /* Ignored options */
 437                 case 'B':
 438                 case 'C':
 439                 case 'd':
 440                 case 'F':
 441                 case 'h':
 442                 case 'N':
 443                 case 'n':
 444                 case 'R':
 445                 case 'U':
 446                 case 'V':
 447                 case 'v':
 448                 case 'X':
 449                         break;
 450
 451                 case ':':
 452                         if (optopt == 'q') {
 453                                 doqueue = 1;
 454                                 break;
 455                         }
 456                         /* FALLTHROUGH */
 457
 458                 default:
 459                         fprintf(stderr, "invalid argument: `-%c'\n", optopt);
 460                         exit(1);
 461                 }
 462         }
 463         argc -= optind;
 464         argv += optind;
 465         opterr = 1;
 466
 467         if (argc != 0 && (showq || doqueue))
 468                 errx(1, "sending mail and queue operations are mutually exclusive");
 469
 470         if (showq + doqueue > 1)
 471                 errx(1, "conflicting queue operations");
 472
 473 skipopts:
 474         if (logident_base == NULL)
 475                 logident_base = "dma";
 476         setlogident(NULL);
 477         set_username();
 478
 479         /* XXX fork root here */
 480
 481         parse_conf(CONF_PATH);
 482
 483         if (config.features & VIRTUAL) {
 484                 if (config.virtualpath == NULL)
 485                         errlogx(1, "no virtuser file specified, but VIRTUAL configured");
 486                 parse_virtuser(config.virtualpath);
 487         }
 488
 489         if (config.authpath != NULL)
 490                 parse_authfile(config.authpath);
 491
 492         if (showq) {
 493                 if (load_queue(&queue) < 0)
 494                         errlog(1, "can not load queue");
 495                 show_queue(&queue);
 496                 return (0);
 497         }
 498
 499         if (doqueue) {
 500                 if (load_queue(&queue) < 0)
 501                         errlog(1, "can not load queue");
 502                 run_queue(&queue);
 503                 return (0);
 504         }
 505
 506         if (read_aliases() != 0)
 507                 errlog(1, "can not read aliases file `%s'", config.aliases);
 508
 509         if ((sender = set_from(&queue, sender)) == NULL)
 510                 errlog(1, NULL);
 511
 512         if (newspoolf(&queue) != 0)
 513                 errlog(1, "can not create temp file");
 514
 515         setlogident("%s", queue.id);
 516
 517         for (i = 0; i < argc; i++) {
 518                 if (add_recp(&queue, argv[i], 1) != 0)
 519                         errlogx(1, "invalid recipient `%s'", argv[i]);
 520         }
 521
 522         if (LIST_EMPTY(&queue.queue) && !recp_from_header)
 523                 errlogx(1, "no recipients");
 524
 525         if (readmail(&queue, nodot, recp_from_header) != 0)
 526                 errlog(1, "can not read mail");
 527
 528         if (LIST_EMPTY(&queue.queue))
 529                 errlogx(1, "no recipients");
 530
 531         if (linkspool(&queue) != 0)
 532                 errlog(1, "can not create spools");
 533
 534         /* From here on the mail is safe. */
 535
 536         if (config.features & DEFER || queue_only)
 537                 return (0);
 538
 539         run_queue(&queue);
 540
 541         /* NOTREACHED */
 542         return (0);
 543 }