src/src/spool_out.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2012 */
   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 if (tls_sni != NULL) fprintf(f, "-tls_sni %s\n", string_printing(tls_sni));
 233 #endif
 234
 235 /* To complete the envelope, write out the tree of non-recipients, followed by
 236 the list of recipients. These won't be disjoint the first time, when no
 237 checking has been done. If a recipient is a "one-time" alias, it is followed by
 238 a space and its parent address number (pno). */
 239
 240 tree_write(tree_nonrecipients, f);
 241 fprintf(f, "%d\n", recipients_count);
 242 for (i = 0; i < recipients_count; i++)
 243   {
 244   recipient_item *r = recipients_list + i;
 245   if (r->pno < 0 && r->errors_to == NULL)
 246     fprintf(f, "%s\n", r->address);
 247   else
 248     {
 249     uschar *errors_to = (r->errors_to == NULL)? US"" : r->errors_to;
 250     fprintf(f, "%s %s %d,%d#1\n", r->address, errors_to,
 251       Ustrlen(errors_to), r->pno);
 252     }
 253   }
 254
 255 /* Put a blank line before the headers */
 256
 257 fprintf(f, "\n");
 258
 259 /* Save the size of the file so far so we can subtract it from the final length
 260 to get the actual size of the headers. */
 261
 262 fflush(f);
 263 fstat(fd, &statbuf);
 264 size_correction = statbuf.st_size;
 265
 266 /* Finally, write out the message's headers. To make it easier to read them
 267 in again, precede each one with the count of its length. Make the count fixed
 268 length to aid human eyes when debugging and arrange for it not be included in
 269 the size. It is followed by a space for normal headers, a flagging letter for
 270 various other headers, or an asterisk for old headers that have been rewritten.
 271 These are saved as a record for debugging. Don't included them in the message's
 272 size. */
 273
 274 for (h = header_list; h != NULL; h = h->next)
 275   {
 276   fprintf(f, "%03d%c %s", h->slen, h->type, h->text);
 277   size_correction += 5;
 278   if (h->type == '*') size_correction += h->slen;
 279   }
 280
 281 /* Flush and check for any errors while writing */
 282
 283 if (fflush(f) != 0 || ferror(f))
 284   return spool_write_error(where, errmsg, US"write", temp_name, f);
 285
 286 /* Force the file's contents to be written to disk. Note that fflush()
 287 just pushes it out of C, and fclose() doesn't guarantee to do the write
 288 either. That's just the way Unix works... */
 289
 290 if (EXIMfsync(fileno(f)) < 0)
 291   return spool_write_error(where, errmsg, US"sync", temp_name, f);
 292
 293 /* Get the size of the file, and close it. */
 294
 295 fstat(fd, &statbuf);
 296 if (fclose(f) != 0)
 297   return spool_write_error(where, errmsg, US"close", temp_name, NULL);
 298
 299 /* Rename the file to its correct name, thereby replacing any previous
 300 incarnation. */
 301
 302 sprintf(CS name, "%s/input/%s/%s-H", spool_directory, message_subdir, id);
 303
 304 if (Urename(temp_name, name) < 0)
 305   return spool_write_error(where, errmsg, US"rename", temp_name, NULL);
 306
 307 /* Linux (and maybe other OS?) does not automatically sync a directory after
 308 an operation like rename. We therefore have to do it forcibly ourselves in
 309 these cases, to make sure the file is actually accessible on disk, as opposed
 310 to just the data being accessible from a file in lost+found. Linux also has
 311 O_DIRECTORY, for opening a directory.
 312
 313 However, it turns out that some file systems (some versions of NFS?) do not
 314 support directory syncing. It seems safe enough to ignore EINVAL to cope with
 315 these cases. One hack on top of another... but that's life. */
 316
 317 #ifdef NEED_SYNC_DIRECTORY
 318
 319 sprintf(CS temp_name, "%s/input/%s/.", spool_directory, message_subdir);
 320
 321 #ifndef O_DIRECTORY
 322 #define O_DIRECTORY 0
 323 #endif
 324
 325 if ((fd = Uopen(temp_name, O_RDONLY|O_DIRECTORY, 0)) < 0)
 326   return spool_write_error(where, errmsg, US"directory open", name, NULL);
 327
 328 if (EXIMfsync(fd) < 0 && errno != EINVAL)
 329   return spool_write_error(where, errmsg, US"directory sync", name, NULL);
 330
 331 if (close(fd) < 0)
 332   return spool_write_error(where, errmsg, US"directory close", name, NULL);
 333
 334 #endif  /* NEED_SYNC_DIRECTORY */
 335
 336 /* Return the number of characters in the headers, which is the file size, less
 337 the prelimary stuff, less the additional count fields on the headers. */
 338
 339 DEBUG(D_receive) debug_printf("Size of headers = %d\n",
 340   (int)(statbuf.st_size - size_correction));
 341
 342 return statbuf.st_size - size_correction;
 343 }
 344
 345
 346 #ifdef SUPPORT_MOVE_FROZEN_MESSAGES
 347
 348 /************************************************
 349 *              Make a hard link                 *
 350 ************************************************/
 351
 352 /* Used by spool_move_message() below. Note re the use of sprintf(): the value
 353 of spool_directory is checked to ensure that it is less than 200 characters at
 354 start-up time.
 355
 356 Arguments:
 357   dir        base directory name
 358   subdir     subdirectory name
 359   id         message id
 360   suffix     suffix to add to id
 361   from       source directory prefix
 362   to         destination directory prefix
 363   noentok    if TRUE, absence of file is not an error
 364
 365 Returns:     TRUE if all went well
 366              FALSE, having panic logged if not
 367 */
 368
 369 static BOOL
 370 make_link(uschar *dir, uschar *subdir, uschar *id, uschar *suffix, uschar *from,
 371   uschar *to, BOOL noentok)
 372 {
 373 uschar f[256], t[256];
 374 sprintf(CS f, "%s/%s%s/%s/%s%s", spool_directory, from, dir, subdir, id, suffix);
 375 sprintf(CS t, "%s/%s%s/%s/%s%s", spool_directory, to, dir, subdir, id, suffix);
 376 if (Ulink(f, t) < 0 && (!noentok || errno != ENOENT))
 377   {
 378   log_write(0, LOG_MAIN|LOG_PANIC, "link(\"%s\", \"%s\") failed while moving "
 379     "message: %s", f, t, strerror(errno));
 380   return FALSE;
 381   }
 382 return TRUE;
 383 }
 384
 385
 386
 387 /************************************************
 388 *                Break a link                   *
 389 ************************************************/
 390
 391 /* Used by spool_move_message() below. Note re the use of sprintf(): the value
 392 of spool_directory is checked to ensure that it is less than 200 characters at
 393 start-up time.
 394
 395 Arguments:
 396   dir        base directory name
 397   subdir     subdirectory name
 398   id         message id
 399   suffix     suffix to add to id
 400   from       source directory prefix
 401   noentok    if TRUE, absence of file is not an error
 402
 403 Returns:     TRUE if all went well
 404              FALSE, having panic logged if not
 405 */
 406
 407 static BOOL
 408 break_link(uschar *dir, uschar *subdir, uschar *id, uschar *suffix, uschar *from,
 409   BOOL noentok)
 410 {
 411 uschar f[256];
 412 sprintf(CS f, "%s/%s%s/%s/%s%s", spool_directory, from, dir, subdir, id, suffix);
 413 if (Uunlink(f) < 0 && (!noentok || errno != ENOENT))
 414   {
 415   log_write(0, LOG_MAIN|LOG_PANIC, "unlink(\"%s\") failed while moving "
 416     "message: %s", f, strerror(errno));
 417   return FALSE;
 418   }
 419 return TRUE;
 420 }
 421
 422
 423
 424 /************************************************
 425 *            Move message files                 *
 426 ************************************************/
 427
 428 /* Move the files for a message (-H, -D, and msglog) from one directory (or
 429 hierarchy) to another. It is assume that there is no -J file in existence when
 430 this is done. At present, this is used only when move_frozen_messages is set,
 431 so compile it only when that support is configured.
 432
 433 Arguments:
 434   id          the id of the message to be delivered
 435   subdir      the subdirectory name, or an empty string
 436   from        a prefix for "input" or "msglog" for where the message is now
 437   to          a prefix for "input" or "msglog" for where the message is to go
 438
 439 Returns:      TRUE if all is well
 440               FALSE if not, with error logged in panic and main logs
 441 */
 442
 443 BOOL
 444 spool_move_message(uschar *id, uschar *subdir, uschar *from, uschar *to)
 445 {
 446 /* Create any output directories that do not exist. */
 447
 448 sprintf(CS big_buffer, "%sinput/%s", to, subdir);
 449 (void)directory_make(spool_directory, big_buffer, INPUT_DIRECTORY_MODE, TRUE);
 450 sprintf(CS big_buffer, "%smsglog/%s", to, subdir);
 451 (void)directory_make(spool_directory, big_buffer, INPUT_DIRECTORY_MODE, TRUE);
 452
 453 /* Move the message by first creating new hard links for all the files, and
 454 then removing the old links. When moving messages onto the main spool, the -H
 455 file should be set up last, because that's the one that tells Exim there is a
 456 message to be delivered, so we create its new link last and remove its old link
 457 first. Programs that look at the alternate directories should follow the same
 458 rule of waiting for a -H file before doing anything. When moving messsages off
 459 the mail spool, the -D file should be open and locked at the time, thus keeping
 460 Exim's hands off. */
 461
 462 if (!make_link(US"msglog", subdir, id, US"", from, to, TRUE) ||
 463     !make_link(US"input",  subdir, id, US"-D", from, to, FALSE) ||
 464     !make_link(US"input",  subdir, id, US"-H", from, to, FALSE))
 465   return FALSE;
 466
 467 if (!break_link(US"input",  subdir, id, US"-H", from, FALSE) ||
 468     !break_link(US"input",  subdir, id, US"-D", from, FALSE) ||
 469     !break_link(US"msglog", subdir, id, US"", from, TRUE))
 470   return FALSE;
 471
 472 log_write(0, LOG_MAIN, "moved from %sinput, %smsglog to %sinput, %smsglog",
 473    from, from, to, to);
 474
 475 return TRUE;
 476 }
 477
 478 #endif
 479
 480 /* End of spool_out.c */