src/src/spool_out.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2009 */
   6 /* See the file NOTICE for conditions of use and distribution. */
   7
   8 /* Functions for writing spool files, and moving them about. */
   9
  10
  11 #include "exim.h"
  12
  13
  14
  15 /*************************************************
  16 *       Deal with header writing errors          *
  17 *************************************************/
  18
  19 /* This function is called immediately after errors in writing the spool, with
  20 errno still set. It creates and error message, depending on the circumstances.
  21 If errmsg is NULL, it logs the message and panic-dies. Otherwise errmsg is set
  22 to point to the message, and -1 is returned. This function makes the code of
  23 spool_write_header() a bit neater.
  24
  25 Arguments:
  26    where      SW_RECEIVING, SW_DELIVERING, or SW_MODIFYING
  27    errmsg     where to put the message; NULL => panic-die
  28    s          text to add to log string
  29    temp_name  name of temp file to unlink
  30    f          FILE to close, if not NULL
  31
  32 Returns:      -1 if errmsg is not NULL; otherwise doesn't return
  33 */
  34
  35 static int
  36 spool_write_error(int where, uschar **errmsg, uschar *s, uschar *temp_name,
  37   FILE *f)
  38 {
  39 uschar *msg = (where == SW_RECEIVING)?
  40   string_sprintf("spool file %s error while receiving from %s: %s", s,
  41     (sender_fullhost != NULL)? sender_fullhost : sender_ident,
  42     strerror(errno))
  43   :
  44   string_sprintf("spool file %s error while %s: %s", s,
  45     (where == SW_DELIVERING)? "delivering" : "modifying",
  46     strerror(errno));
  47
  48 if (temp_name != NULL) Uunlink(temp_name);
  49 if (f != NULL) (void)fclose(f);
  50
  51 if (errmsg == NULL)
  52   log_write(0, LOG_MAIN|LOG_PANIC_DIE, "%s", msg);
  53 else
  54   *errmsg = msg;
  55
  56 return -1;
  57 }
  58
  59
  60
  61 /*************************************************
  62 *            Open file under temporary name      *
  63 *************************************************/
  64
  65 /* This is used for opening spool files under a temporary name,
  66 with a single attempt at deleting if they already exist.
  67
  68 Argument: temporary name for spool header file
  69 Returns:  file descriptor of open file, or < 0 on failure, with errno unchanged
  70 */
  71
  72 int
  73 spool_open_temp(uschar *temp_name)
  74 {
  75 int fd = Uopen(temp_name, O_RDWR|O_CREAT|O_EXCL, SPOOL_MODE);
  76
  77 /* If the file already exists, something has gone wrong. This process may well
  78 have previously created the file if it is delivering more than one address, but
  79 it should have renamed it almost immediately. A file could, however, be left
  80 around as a result of a system crash, and by coincidence this process might
  81 have the same pid. We therefore have one go at unlinking it before giving up.
  82 */
  83
  84 if (fd < 0 && errno == EEXIST)
  85   {
  86   DEBUG(D_any) debug_printf("%s exists: unlinking\n", temp_name);
  87   Uunlink(temp_name);
  88   fd = Uopen(temp_name, O_RDWR|O_CREAT|O_EXCL, SPOOL_MODE);
  89   }
  90
  91 /* If the file has been opened, make sure the file's group is the Exim gid, and
  92 double-check the mode because the group setting doesn't always get set
  93 automatically. */
  94
  95 if (fd >= 0)
  96   {
  97   (void)fchown(fd, exim_uid, exim_gid);
  98   (void)fchmod(fd, SPOOL_MODE);
  99   }
 100
 101 return fd;
 102 }
 103
 104
 105
 106 /*************************************************
 107 *          Write the header spool file           *
 108 *************************************************/
 109
 110 /* Returns the size of the file for success; zero for failure. The file is
 111 written under a temporary name, and then renamed. It's done this way so that it
 112 works with re-writing the file on message deferral as well as for the initial
 113 write. Whenever this function is called, the data file for the message should
 114 be open and locked, thus preventing any other exim process from working on this
 115 message.
 116
 117 Argument:
 118   id      the message id
 119   where   SW_RECEIVING, SW_DELIVERING, or SW_MODIFYING
 120   errmsg  where to put an error message; if NULL, panic-die on error
 121
 122 Returns:  the size of the header texts on success;
 123           negative on writing failure, unless errmsg == NULL
 124 */
 125
 126 int
 127 spool_write_header(uschar *id, int where, uschar **errmsg)
 128 {
 129 int fd;
 130 int i;
 131 int size_correction;
 132 FILE *f;
 133 header_line *h;
 134 struct stat statbuf;
 135 uschar name[256];
 136 uschar temp_name[256];
 137
 138 sprintf(CS temp_name, "%s/input/%s/hdr.%d", spool_directory, message_subdir,
 139   (int)getpid());
 140 fd = spool_open_temp(temp_name);
 141 if (fd < 0) return spool_write_error(where, errmsg, US"open", NULL, NULL);
 142 f = fdopen(fd, "wb");
 143 DEBUG(D_receive|D_deliver) debug_printf("Writing spool header file\n");
 144
 145 /* We now have an open file to which the header data is to be written. Start
 146 with the file's leaf name, to make the file self-identifying. Continue with the
 147 identity of the submitting user, followed by the sender's address. The sender's
 148 address is enclosed in <> because it might be the null address. Then write the
 149 received time and the number of warning messages that have been sent. */
 150
 151 fprintf(f, "%s-H\n", message_id);
 152 fprintf(f, "%.63s %ld %ld\n", originator_login, (long int)originator_uid,
 153   (long int)originator_gid);
 154 fprintf(f, "<%s>\n", sender_address);
 155 fprintf(f, "%d %d\n", received_time, warning_count);
 156
 157 /* If there is information about a sending host, remember it. The HELO
 158 data can be set for local SMTP as well as remote. */
 159
 160 if (sender_helo_name != NULL)
 161   fprintf(f, "-helo_name %s\n", sender_helo_name);
 162
 163 if (sender_host_address != NULL)
 164   {
 165   fprintf(f, "-host_address %s.%d\n", sender_host_address, sender_host_port);
 166   if (sender_host_name != NULL)
 167     fprintf(f, "-host_name %s\n", sender_host_name);
 168   if (sender_host_authenticated != NULL)
 169     fprintf(f, "-host_auth %s\n", sender_host_authenticated);
 170   }
 171
 172 /* Also about the interface a message came in on */
 173
 174 if (interface_address != NULL)
 175   fprintf(f, "-interface_address %s.%d\n", interface_address, interface_port);
 176
 177 if (smtp_active_hostname != primary_hostname)
 178   fprintf(f, "-active_hostname %s\n", smtp_active_hostname);
 179
 180 /* Likewise for any ident information; for local messages this is
 181 likely to be the same as originator_login, but will be different if
 182 the originator was root, forcing a different ident. */
 183
 184 if (sender_ident != NULL) fprintf(f, "-ident %s\n", sender_ident);
 185
 186 /* Ditto for the received protocol */
 187
 188 if (received_protocol != NULL)
 189   fprintf(f, "-received_protocol %s\n", received_protocol);
 190
 191 /* Preserve any ACL variables that are set. */
 192
 193 tree_walk(acl_var_c, &acl_var_write, f);
 194 tree_walk(acl_var_m, &acl_var_write, f);
 195
 196 /* Now any other data that needs to be remembered. */
 197
 198 fprintf(f, "-body_linecount %d\n", body_linecount);
 199 fprintf(f, "-max_received_linelength %d\n", max_received_linelength);
 200
 201 if (body_zerocount > 0) fprintf(f, "-body_zerocount %d\n", body_zerocount);
 202
 203 if (authenticated_id != NULL)
 204   fprintf(f, "-auth_id %s\n", authenticated_id);
 205 if (authenticated_sender != NULL)
 206   fprintf(f, "-auth_sender %s\n", authenticated_sender);
 207
 208 if (allow_unqualified_recipient) fprintf(f, "-allow_unqualified_recipient\n");
 209 if (allow_unqualified_sender) fprintf(f, "-allow_unqualified_sender\n");
 210 if (deliver_firsttime) fprintf(f, "-deliver_firsttime\n");
 211 if (deliver_freeze) fprintf(f, "-frozen %d\n", deliver_frozen_at);
 212 if (dont_deliver) fprintf(f, "-N\n");
 213 if (host_lookup_deferred) fprintf(f, "-host_lookup_deferred\n");
 214 if (host_lookup_failed) fprintf(f, "-host_lookup_failed\n");
 215 if (sender_local) fprintf(f, "-local\n");
 216 if (local_error_message) fprintf(f, "-localerror\n");
 217 if (local_scan_data != NULL) fprintf(f, "-local_scan %s\n", local_scan_data);
 218 #ifdef WITH_CONTENT_SCAN
 219 if (spam_score_int != NULL) fprintf(f,"-spam_score_int %s\n", spam_score_int);
 220 #endif
 221 if (deliver_manual_thaw) fprintf(f, "-manual_thaw\n");
 222 if (sender_set_untrusted) fprintf(f, "-sender_set_untrusted\n");
 223
 224 #ifdef EXPERIMENTAL_BRIGHTMAIL
 225 if (bmi_verdicts != NULL) fprintf(f, "-bmi_verdicts %s\n", bmi_verdicts);
 226 #endif
 227
 228 #ifdef SUPPORT_TLS
 229 if (tls_certificate_verified) fprintf(f, "-tls_certificate_verified\n");
 230 if (tls_cipher != NULL) fprintf(f, "-tls_cipher %s\n", tls_cipher);
 231 if (tls_peerdn != NULL) fprintf(f, "-tls_peerdn %s\n", string_printing(tls_peerdn));
 232 #endif
 233
 234 /* To complete the envelope, write out the tree of non-recipients, followed by
 235 the list of recipients. These won't be disjoint the first time, when no
 236 checking has been done. If a recipient is a "one-time" alias, it is followed by
 237 a space and its parent address number (pno). */
 238
 239 tree_write(tree_nonrecipients, f);
 240 fprintf(f, "%d\n", recipients_count);
 241 for (i = 0; i < recipients_count; i++)
 242   {
 243   recipient_item *r = recipients_list + i;
 244   if (r->pno < 0 && r->errors_to == NULL)
 245     fprintf(f, "%s\n", r->address);
 246   else
 247     {
 248     uschar *errors_to = (r->errors_to == NULL)? US"" : r->errors_to;
 249     fprintf(f, "%s %s %d,%d#1\n", r->address, errors_to,
 250       Ustrlen(errors_to), r->pno);
 251     }
 252   }
 253
 254 /* Put a blank line before the headers */
 255
 256 fprintf(f, "\n");
 257
 258 /* Save the size of the file so far so we can subtract it from the final length
 259 to get the actual size of the headers. */
 260
 261 fflush(f);
 262 fstat(fd, &statbuf);
 263 size_correction = statbuf.st_size;
 264
 265 /* Finally, write out the message's headers. To make it easier to read them
 266 in again, precede each one with the count of its length. Make the count fixed
 267 length to aid human eyes when debugging and arrange for it not be included in
 268 the size. It is followed by a space for normal headers, a flagging letter for
 269 various other headers, or an asterisk for old headers that have been rewritten.
 270 These are saved as a record for debugging. Don't included them in the message's
 271 size. */
 272
 273 for (h = header_list; h != NULL; h = h->next)
 274   {
 275   fprintf(f, "%03d%c %s", h->slen, h->type, h->text);
 276   size_correction += 5;
 277   if (h->type == '*') size_correction += h->slen;
 278   }
 279
 280 /* Flush and check for any errors while writing */
 281
 282 if (fflush(f) != 0 || ferror(f))
 283   return spool_write_error(where, errmsg, US"write", temp_name, f);
 284
 285 /* Force the file's contents to be written to disk. Note that fflush()
 286 just pushes it out of C, and fclose() doesn't guarantee to do the write
 287 either. That's just the way Unix works... */
 288
 289 if (EXIMfsync(fileno(f)) < 0)
 290   return spool_write_error(where, errmsg, US"sync", temp_name, f);
 291
 292 /* Get the size of the file, and close it. */
 293
 294 fstat(fd, &statbuf);
 295 if (fclose(f) != 0)
 296   return spool_write_error(where, errmsg, US"close", temp_name, NULL);
 297
 298 /* Rename the file to its correct name, thereby replacing any previous
 299 incarnation. */
 300
 301 sprintf(CS name, "%s/input/%s/%s-H", spool_directory, message_subdir, id);
 302
 303 if (Urename(temp_name, name) < 0)
 304   return spool_write_error(where, errmsg, US"rename", temp_name, NULL);
 305
 306 /* Linux (and maybe other OS?) does not automatically sync a directory after
 307 an operation like rename. We therefore have to do it forcibly ourselves in
 308 these cases, to make sure the file is actually accessible on disk, as opposed
 309 to just the data being accessible from a file in lost+found. Linux also has
 310 O_DIRECTORY, for opening a directory.
 311
 312 However, it turns out that some file systems (some versions of NFS?) do not
 313 support directory syncing. It seems safe enough to ignore EINVAL to cope with
 314 these cases. One hack on top of another... but that's life. */
 315
 316 #ifdef NEED_SYNC_DIRECTORY
 317
 318 sprintf(CS temp_name, "%s/input/%s/.", spool_directory, message_subdir);
 319
 320 #ifndef O_DIRECTORY
 321 #define O_DIRECTORY 0
 322 #endif
 323
 324 if ((fd = Uopen(temp_name, O_RDONLY|O_DIRECTORY, 0)) < 0)
 325   return spool_write_error(where, errmsg, US"directory open", name, NULL);
 326
 327 if (EXIMfsync(fd) < 0 && errno != EINVAL)
 328   return spool_write_error(where, errmsg, US"directory sync", name, NULL);
 329
 330 if (close(fd) < 0)
 331   return spool_write_error(where, errmsg, US"directory close", name, NULL);
 332
 333 #endif  /* NEED_SYNC_DIRECTORY */
 334
 335 /* Return the number of characters in the headers, which is the file size, less
 336 the prelimary stuff, less the additional count fields on the headers. */
 337
 338 DEBUG(D_receive) debug_printf("Size of headers = %d\n",
 339   (int)(statbuf.st_size - size_correction));
 340
 341 return statbuf.st_size - size_correction;
 342 }
 343
 344
 345 #ifdef SUPPORT_MOVE_FROZEN_MESSAGES
 346
 347 /************************************************
 348 *              Make a hard link                 *
 349 ************************************************/
 350
 351 /* Used by spool_move_message() below. Note re the use of sprintf(): the value
 352 of spool_directory is checked to ensure that it is less than 200 characters at
 353 start-up time.
 354
 355 Arguments:
 356   dir        base directory name
 357   subdir     subdirectory name
 358   id         message id
 359   suffix     suffix to add to id
 360   from       source directory prefix
 361   to         destination directory prefix
 362   noentok    if TRUE, absence of file is not an error
 363
 364 Returns:     TRUE if all went well
 365              FALSE, having panic logged if not
 366 */
 367
 368 static BOOL
 369 make_link(uschar *dir, uschar *subdir, uschar *id, uschar *suffix, uschar *from,
 370   uschar *to, BOOL noentok)
 371 {
 372 uschar f[256], t[256];
 373 sprintf(CS f, "%s/%s%s/%s/%s%s", spool_directory, from, dir, subdir, id, suffix);
 374 sprintf(CS t, "%s/%s%s/%s/%s%s", spool_directory, to, dir, subdir, id, suffix);
 375 if (Ulink(f, t) < 0 && (!noentok || errno != ENOENT))
 376   {
 377   log_write(0, LOG_MAIN|LOG_PANIC, "link(\"%s\", \"%s\") failed while moving "
 378     "message: %s", f, t, strerror(errno));
 379   return FALSE;
 380   }
 381 return TRUE;
 382 }
 383
 384
 385
 386 /************************************************
 387 *                Break a link                   *
 388 ************************************************/
 389
 390 /* Used by spool_move_message() below. Note re the use of sprintf(): the value
 391 of spool_directory is checked to ensure that it is less than 200 characters at
 392 start-up time.
 393
 394 Arguments:
 395   dir        base directory name
 396   subdir     subdirectory name
 397   id         message id
 398   suffix     suffix to add to id
 399   from       source directory prefix
 400   noentok    if TRUE, absence of file is not an error
 401
 402 Returns:     TRUE if all went well
 403              FALSE, having panic logged if not
 404 */
 405
 406 static BOOL
 407 break_link(uschar *dir, uschar *subdir, uschar *id, uschar *suffix, uschar *from,
 408   BOOL noentok)
 409 {
 410 uschar f[256];
 411 sprintf(CS f, "%s/%s%s/%s/%s%s", spool_directory, from, dir, subdir, id, suffix);
 412 if (Uunlink(f) < 0 && (!noentok || errno != ENOENT))
 413   {
 414   log_write(0, LOG_MAIN|LOG_PANIC, "unlink(\"%s\") failed while moving "
 415     "message: %s", f, strerror(errno));
 416   return FALSE;
 417   }
 418 return TRUE;
 419 }
 420
 421
 422
 423 /************************************************
 424 *            Move message files                 *
 425 ************************************************/
 426
 427 /* Move the files for a message (-H, -D, and msglog) from one directory (or
 428 hierarchy) to another. It is assume that there is no -J file in existence when
 429 this is done. At present, this is used only when move_frozen_messages is set,
 430 so compile it only when that support is configured.
 431
 432 Arguments:
 433   id          the id of the message to be delivered
 434   subdir      the subdirectory name, or an empty string
 435   from        a prefix for "input" or "msglog" for where the message is now
 436   to          a prefix for "input" or "msglog" for where the message is to go
 437
 438 Returns:      TRUE if all is well
 439               FALSE if not, with error logged in panic and main logs
 440 */
 441
 442 BOOL
 443 spool_move_message(uschar *id, uschar *subdir, uschar *from, uschar *to)
 444 {
 445 /* Create any output directories that do not exist. */
 446
 447 sprintf(CS big_buffer, "%sinput/%s", to, subdir);
 448 (void)directory_make(spool_directory, big_buffer, INPUT_DIRECTORY_MODE, TRUE);
 449 sprintf(CS big_buffer, "%smsglog/%s", to, subdir);
 450 (void)directory_make(spool_directory, big_buffer, INPUT_DIRECTORY_MODE, TRUE);
 451
 452 /* Move the message by first creating new hard links for all the files, and
 453 then removing the old links. When moving messages onto the main spool, the -H
 454 file should be set up last, because that's the one that tells Exim there is a
 455 message to be delivered, so we create its new link last and remove its old link
 456 first. Programs that look at the alternate directories should follow the same
 457 rule of waiting for a -H file before doing anything. When moving messsages off
 458 the mail spool, the -D file should be open and locked at the time, thus keeping
 459 Exim's hands off. */
 460
 461 if (!make_link(US"msglog", subdir, id, US"", from, to, TRUE) ||
 462     !make_link(US"input",  subdir, id, US"-D", from, to, FALSE) ||
 463     !make_link(US"input",  subdir, id, US"-H", from, to, FALSE))
 464   return FALSE;
 465
 466 if (!break_link(US"input",  subdir, id, US"-H", from, FALSE) ||
 467     !break_link(US"input",  subdir, id, US"-D", from, FALSE) ||
 468     !break_link(US"msglog", subdir, id, US"", from, TRUE))
 469   return FALSE;
 470
 471 log_write(0, LOG_MAIN, "moved from %sinput, %smsglog to %sinput, %smsglog",
 472    from, from, to, to);
 473
 474 return TRUE;
 475 }
 476
 477 #endif
 478
 479 /* End of spool_out.c */