spool.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/stat.h>
  36
  37 #include <ctype.h>
  38 #include <dirent.h>
  39 #include <err.h>
  40 #include <errno.h>
  41 #include <fcntl.h>
  42 #include <inttypes.h>
  43 #include <unistd.h>
  44 #include <syslog.h>
  45
  46 #include "dma.h"
  47
  48 /*
  49  * Spool file format:
  50  *
  51  * 'Q'id files (queue):
  52  *   Organized like an RFC822 header, field: value.  Ignores unknown fields.
  53  *   ID: id
  54  *   Sender: envelope-from
  55  *   Recipient: envelope-to
  56  *
  57  * 'M'id files (data):
  58  *   mail data
  59  *
  60  * Each queue file needs to have a corresponding data file.
  61  * One data file might be shared by linking it several times.
  62  *
  63  * Queue ids are unique, formed from the inode of the data file
  64  * and a unique identifier.
  65  */
  66
  67 int
  68 newspoolf(struct queue *queue)
  69 {
  70         char fn[PATH_MAX+1];
  71         struct stat st;
  72         struct stritem *t;
  73         int fd;
  74
  75         if (snprintf(fn, sizeof(fn), "%s/%s", config.spooldir, "tmp_XXXXXXXXXX") <= 0)
  76                 return (-1);
  77
  78         fd = mkstemp(fn);
  79         if (fd < 0)
  80                 return (-1);
  81         /* XXX group rights */
  82         if (fchmod(fd, 0660) < 0)
  83                 goto fail;
  84         if (flock(fd, LOCK_EX) == -1)
  85                 goto fail;
  86         queue->tmpf = strdup(fn);
  87         if (queue->tmpf == NULL)
  88                 goto fail;
  89
  90         /*
  91          * Assign queue id
  92          */
  93         if (fstat(fd, &st) != 0)
  94                 goto fail;
  95         if (asprintf(&queue->id, "%"PRIxMAX, st.st_ino) < 0)
  96                 goto fail;
  97
  98         queue->mailf = fdopen(fd, "r+");
  99         if (queue->mailf == NULL)
 100                 goto fail;
 101
 102         t = malloc(sizeof(*t));
 103         if (t != NULL) {
 104                 t->str = queue->tmpf;
 105                 SLIST_INSERT_HEAD(&tmpfs, t, next);
 106         }
 107         return (0);
 108
 109 fail:
 110         if (queue->mailf != NULL)
 111                 fclose(queue->mailf);
 112         close(fd);
 113         unlink(fn);
 114         return (-1);
 115 }
 116
 117 static int
 118 writequeuef(struct qitem *it)
 119 {
 120         int error;
 121         int queuefd;
 122
 123         queuefd = open_locked(it->queuefn, O_CREAT|O_EXCL|O_RDWR, 0600);
 124         if (queuefd == -1)
 125                 return (-1);
 126         it->queuef = fdopen(queuefd, "w+");
 127         if (it->queuef == NULL)
 128                 return (-1);
 129
 130         error = fprintf(it->queuef,
 131                         "ID: %s\n"
 132                         "Sender: %s\n"
 133                         "Recipient: %s\n",
 134                          it->queueid,
 135                          it->sender,
 136                          it->addr);
 137
 138         if (error <= 0)
 139                 return (-1);
 140
 141         if (fflush(it->queuef) != 0 || fsync(fileno(it->queuef)) != 0)
 142                 return (-1);
 143
 144         return (0);
 145 }
 146
 147 static struct qitem *
 148 readqueuef(struct queue *queue, char *queuefn)
 149 {
 150         char line[1000];
 151         struct queue itmqueue;
 152         FILE *queuef = NULL;
 153         char *s;
 154         char *queueid = NULL, *sender = NULL, *addr = NULL;
 155         struct qitem *it = NULL;
 156
 157         bzero(&itmqueue, sizeof(itmqueue));
 158         LIST_INIT(&itmqueue.queue);
 159
 160         queuef = fopen(queuefn, "r");
 161         if (queuef == NULL)
 162                 goto out;
 163
 164         while (!feof(queuef)) {
 165                 if (fgets(line, sizeof(line), queuef) == NULL || line[0] == 0)
 166                         break;
 167                 line[strlen(line) - 1] = 0;     /* chop newline */
 168
 169                 s = strchr(line, ':');
 170                 if (s == NULL)
 171                         goto malformed;
 172                 *s = 0;
 173
 174                 s++;
 175                 while (isspace(*s))
 176                         s++;
 177
 178                 s = strdup(s);
 179                 if (s == NULL)
 180                         goto malformed;
 181
 182                 if (strcmp(line, "ID") == 0) {
 183                         queueid = s;
 184                 } else if (strcmp(line, "Sender") == 0) {
 185                         sender = s;
 186                 } else if (strcmp(line, "Recipient") == 0) {
 187                         addr = s;
 188                 } else {
 189                         syslog(LOG_DEBUG, "ignoring unknown queue info `%s' in `%s'",
 190                                line, queuefn);
 191                         free(s);
 192                 }
 193         }
 194
 195         if (queueid == NULL || sender == NULL || addr == NULL ||
 196             *queueid == 0 || *addr == 0) {
 197 malformed:
 198                 errno = EINVAL;
 199                 syslog(LOG_ERR, "malformed queue file `%s'", queuefn);
 200                 goto out;
 201         }
 202
 203         if (add_recp(&itmqueue, addr, 0) != 0)
 204                 goto out;
 205
 206         it = LIST_FIRST(&itmqueue.queue);
 207         it->sender = sender; sender = NULL;
 208         it->queueid = queueid; queueid = NULL;
 209         it->queuefn = queuefn; queuefn = NULL;
 210         LIST_INSERT_HEAD(&queue->queue, it, next);
 211
 212 out:
 213         if (sender != NULL)
 214                 free(sender);
 215         if (queueid != NULL)
 216                 free(queueid);
 217         if (addr != NULL)
 218                 free(addr);
 219         if (queuef != NULL)
 220                 fclose(queuef);
 221
 222         return (it);
 223 }
 224
 225 int
 226 linkspool(struct queue *queue)
 227 {
 228         struct stat st;
 229         struct qitem *it;
 230
 231         if (fflush(queue->mailf) != 0 || fsync(fileno(queue->mailf)) != 0)
 232                 goto delfiles;
 233
 234         syslog(LOG_INFO, "new mail from user=%s uid=%d envelope_from=<%s>",
 235                username, getuid(), queue->sender);
 236
 237         LIST_FOREACH(it, &queue->queue, next) {
 238                 if (asprintf(&it->queueid, "%s.%"PRIxPTR, queue->id, (uintptr_t)it) <= 0)
 239                         goto delfiles;
 240                 if (asprintf(&it->queuefn, "%s/Q%s", config.spooldir, it->queueid) <= 0)
 241                         goto delfiles;
 242                 if (asprintf(&it->mailfn, "%s/M%s", config.spooldir, it->queueid) <= 0)
 243                         goto delfiles;
 244
 245                 /* Neither file may not exist yet */
 246                 if (stat(it->queuefn, &st) == 0 || stat(it->mailfn, &st) == 0)
 247                         goto delfiles;
 248
 249                 if (writequeuef(it) != 0)
 250                         goto delfiles;
 251
 252                 if (link(queue->tmpf, it->mailfn) != 0)
 253                         goto delfiles;
 254         }
 255
 256         LIST_FOREACH(it, &queue->queue, next) {
 257                 syslog(LOG_INFO, "mail to=<%s> queued as %s",
 258                        it->addr, it->queueid);
 259         }
 260
 261         unlink(queue->tmpf);
 262         return (0);
 263
 264 delfiles:
 265         LIST_FOREACH(it, &queue->queue, next) {
 266                 unlink(it->mailfn);
 267                 unlink(it->queuefn);
 268         }
 269         return (-1);
 270 }
 271
 272 int
 273 load_queue(struct queue *queue)
 274 {
 275         struct stat sb;
 276         struct qitem *it;
 277         DIR *spooldir;
 278         struct dirent *de;
 279         char *queuefn;
 280         char *mailfn;
 281
 282         bzero(queue, sizeof(queue));
 283         LIST_INIT(&queue->queue);
 284
 285         spooldir = opendir(config.spooldir);
 286         if (spooldir == NULL)
 287                 err(1, "reading queue");
 288
 289         while ((de = readdir(spooldir)) != NULL) {
 290                 queuefn = NULL;
 291                 mailfn = NULL;
 292
 293                 /* ignore temp files */
 294                 if (strncmp(de->d_name, "tmp_", 4) == 0 || de->d_type != DT_REG)
 295                         continue;
 296                 if (de->d_name[0] != 'Q')
 297                         continue;
 298                 if (asprintf(&queuefn, "%s/Q%s", config.spooldir, de->d_name + 1) < 0)
 299                         goto fail;
 300                 if (asprintf(&mailfn, "%s/M%s", config.spooldir, de->d_name + 1) < 0)
 301                         goto fail;
 302
 303                 if (stat(mailfn, &sb) != 0)
 304                         goto skip_item;
 305
 306                 it = readqueuef(queue, queuefn);
 307                 if (it == NULL)
 308                         goto skip_item;
 309
 310                 it->mailfn = mailfn;
 311                 continue;
 312
 313 skip_item:
 314                 syslog(LOG_INFO, "could not pick up queue file: `%s'/`%s': %m", queuefn, mailfn);
 315                 if (queuefn != NULL)
 316                         free(queuefn);
 317                 if (mailfn != NULL)
 318                         free(queuefn);
 319         }
 320         closedir(spooldir);
 321         return (0);
 322
 323 fail:
 324         return (-1);
 325 }
 326
 327 void
 328 delqueue(struct qitem *it)
 329 {
 330         unlink(it->mailfn);
 331         unlink(it->queuefn);
 332         if (it->queuef != NULL)
 333                 fclose(it->queuef);
 334         if (it->mailf != NULL)
 335                 fclose(it->mailf);
 336         free(it);
 337 }
 338
 339 int
 340 acquirespool(struct qitem *it)
 341 {
 342         int queuefd;
 343
 344         if (it->queuef == NULL) {
 345                 queuefd = open_locked(it->queuefn, O_RDWR|O_NONBLOCK);
 346                 if (queuefd < 0)
 347                         goto fail;
 348                 it->queuef = fdopen(queuefd, "r+");
 349                 if (it->queuef == NULL)
 350                         goto fail;
 351         }
 352
 353         if (it->mailf == NULL) {
 354                 it->mailf = fopen(it->mailfn, "r");
 355                 if (it->mailf == NULL)
 356                         goto fail;
 357         }
 358
 359         return (0);
 360
 361 fail:
 362         syslog(LOG_INFO, "could not acquire queue file: %m");
 363         return (-1);
 364 }
 365
 366 void
 367 dropspool(struct queue *queue, struct qitem *keep)
 368 {
 369         struct qitem *it;
 370
 371         LIST_FOREACH(it, &queue->queue, next) {
 372                 if (it == keep)
 373                         continue;
 374
 375                 if (it->queuef != NULL)
 376                         fclose(it->queuef);
 377                 if (it->mailf != NULL)
 378                         fclose(it->mailf);
 379         }
 380 }