src/spool_out.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2016 */
   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 an 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 ? sender_fullhost : sender_ident,
  42       strerror(errno))
  43   : string_sprintf("spool file %s error while %s: %s", s,
  44       where == SW_DELIVERING ? "delivering" : "modifying",
  45       strerror(errno));
  46
  47 if (temp_name) Uunlink(temp_name);
  48 if (f) (void)fclose(f);
  49
  50 if (errmsg)
  51   *errmsg = msg;
  52 else
  53   log_write(0, LOG_MAIN|LOG_PANIC_DIE, "%s", msg);
  54
  55 return -1;
  56 }
  57
  58
  59
  60 /*************************************************
  61 *            Open file under temporary name      *
  62 *************************************************/
  63
  64 /* This is used for opening spool files under a temporary name,
  65 with a single attempt at deleting if they already exist.
  66
  67 Argument: temporary name for spool header file
  68 Returns:  file descriptor of open file, or < 0 on failure, with errno unchanged
  69 */
  70
  71 int
  72 spool_open_temp(uschar *temp_name)
  73 {
  74 int fd = Uopen(temp_name, O_RDWR|O_CREAT|O_EXCL, SPOOL_MODE);
  75
  76 /* If the file already exists, something has gone wrong. This process may well
  77 have previously created the file if it is delivering more than one address, but
  78 it should have renamed it almost immediately. A file could, however, be left
  79 around as a result of a system crash, and by coincidence this process might
  80 have the same pid. We therefore have one go at unlinking it before giving up.
  81 */
  82
  83 if (fd < 0 && errno == EEXIST)
  84   {
  85   DEBUG(D_any) debug_printf("%s exists: unlinking\n", temp_name);
  86   Uunlink(temp_name);
  87   fd = Uopen(temp_name, O_RDWR|O_CREAT|O_EXCL, SPOOL_MODE);
  88   }
  89
  90 /* If the file has been opened, make sure the file's group is the Exim gid, and
  91 double-check the mode because the group setting doesn't always get set
  92 automatically. */
  93
  94 if (fd >= 0)
  95   if (fchown(fd, exim_uid, exim_gid) || fchmod(fd, SPOOL_MODE))
  96     {
  97     DEBUG(D_any) debug_printf("failed setting perms on %s\n", temp_name);
  98     (void) close(fd); fd = -1;
  99     Uunlink(temp_name);
 100     }
 101
 102 return fd;
 103 }
 104
 105
 106
 107 /*************************************************
 108 *          Write the header spool file           *
 109 *************************************************/
 110
 111 /* Returns the size of the file for success; zero for failure. The file is
 112 written under a temporary name, and then renamed. It's done this way so that it
 113 works with re-writing the file on message deferral as well as for the initial
 114 write. Whenever this function is called, the data file for the message should
 115 be open and locked, thus preventing any other exim process from working on this
 116 message.
 117
 118 Argument:
 119   id      the message id
 120   where   SW_RECEIVING, SW_DELIVERING, or SW_MODIFYING
 121   errmsg  where to put an error message; if NULL, panic-die on error
 122
 123 Returns:  the size of the header texts on success;
 124           negative on writing failure, unless errmsg == NULL
 125 */
 126
 127 int
 128 spool_write_header(uschar *id, int where, uschar **errmsg)
 129 {
 130 int fd;
 131 int i;
 132 int size_correction;
 133 FILE *f;
 134 header_line *h;
 135 struct stat statbuf;
 136 uschar * tname;
 137 uschar * fname;
 138
 139 tname = spool_fname(US"input", message_subdir,
 140                     string_sprintf("hdr.%d", (int)getpid()), US"");
 141
 142 if ((fd = spool_open_temp(tname)) < 0)
 143   return spool_write_error(where, errmsg, US"open", NULL, NULL);
 144 f = fdopen(fd, "wb");
 145 DEBUG(D_receive|D_deliver) debug_printf("Writing spool header file: %s\n", tname);
 146
 147 /* We now have an open file to which the header data is to be written. Start
 148 with the file's leaf name, to make the file self-identifying. Continue with the
 149 identity of the submitting user, followed by the sender's address. The sender's
 150 address is enclosed in <> because it might be the null address. Then write the
 151 received time and the number of warning messages that have been sent. */
 152
 153 fprintf(f, "%s-H\n", message_id);
 154 fprintf(f, "%.63s %ld %ld\n", originator_login, (long int)originator_uid,
 155   (long int)originator_gid);
 156 fprintf(f, "<%s>\n", sender_address);
 157 fprintf(f, "%d %d\n", received_time, warning_count);
 158
 159 /* If there is information about a sending host, remember it. The HELO
 160 data can be set for local SMTP as well as remote. */
 161
 162 if (sender_helo_name != NULL)
 163   fprintf(f, "-helo_name %s\n", sender_helo_name);
 164
 165 if (sender_host_address != NULL)
 166   {
 167   fprintf(f, "-host_address %s.%d\n", sender_host_address, sender_host_port);
 168   if (sender_host_name != NULL)
 169     fprintf(f, "-host_name %s\n", sender_host_name);
 170   if (sender_host_authenticated != NULL)
 171     fprintf(f, "-host_auth %s\n", sender_host_authenticated);
 172   }
 173
 174 /* Also about the interface a message came in on */
 175
 176 if (interface_address != NULL)
 177   fprintf(f, "-interface_address %s.%d\n", interface_address, interface_port);
 178
 179 if (smtp_active_hostname != primary_hostname)
 180   fprintf(f, "-active_hostname %s\n", smtp_active_hostname);
 181
 182 /* Likewise for any ident information; for local messages this is
 183 likely to be the same as originator_login, but will be different if
 184 the originator was root, forcing a different ident. */
 185
 186 if (sender_ident != NULL) fprintf(f, "-ident %s\n", sender_ident);
 187
 188 /* Ditto for the received protocol */
 189
 190 if (received_protocol != NULL)
 191   fprintf(f, "-received_protocol %s\n", received_protocol);
 192
 193 /* Preserve any ACL variables that are set. */
 194
 195 tree_walk(acl_var_c, &acl_var_write, f);
 196 tree_walk(acl_var_m, &acl_var_write, f);
 197
 198 /* Now any other data that needs to be remembered. */
 199
 200 fprintf(f, "-body_linecount %d\n", body_linecount);
 201 fprintf(f, "-max_received_linelength %d\n", max_received_linelength);
 202
 203 if (body_zerocount > 0) fprintf(f, "-body_zerocount %d\n", body_zerocount);
 204
 205 if (authenticated_id != NULL)
 206   fprintf(f, "-auth_id %s\n", authenticated_id);
 207 if (authenticated_sender != NULL)
 208   fprintf(f, "-auth_sender %s\n", authenticated_sender);
 209
 210 if (allow_unqualified_recipient) fprintf(f, "-allow_unqualified_recipient\n");
 211 if (allow_unqualified_sender) fprintf(f, "-allow_unqualified_sender\n");
 212 if (deliver_firsttime) fprintf(f, "-deliver_firsttime\n");
 213 if (deliver_freeze) fprintf(f, "-frozen " TIME_T_FMT "\n", deliver_frozen_at);
 214 if (dont_deliver) fprintf(f, "-N\n");
 215 if (host_lookup_deferred) fprintf(f, "-host_lookup_deferred\n");
 216 if (host_lookup_failed) fprintf(f, "-host_lookup_failed\n");
 217 if (sender_local) fprintf(f, "-local\n");
 218 if (local_error_message) fprintf(f, "-localerror\n");
 219 if (local_scan_data != NULL) fprintf(f, "-local_scan %s\n", local_scan_data);
 220 #ifdef WITH_CONTENT_SCAN
 221 if (spam_bar)       fprintf(f,"-spam_bar %s\n",       spam_bar);
 222 if (spam_score)     fprintf(f,"-spam_score %s\n",     spam_score);
 223 if (spam_score_int) fprintf(f,"-spam_score_int %s\n", spam_score_int);
 224 #endif
 225 if (deliver_manual_thaw) fprintf(f, "-manual_thaw\n");
 226 if (sender_set_untrusted) fprintf(f, "-sender_set_untrusted\n");
 227
 228 #ifdef EXPERIMENTAL_BRIGHTMAIL
 229 if (bmi_verdicts != NULL) fprintf(f, "-bmi_verdicts %s\n", bmi_verdicts);
 230 #endif
 231
 232 #ifdef SUPPORT_TLS
 233 if (tls_in.certificate_verified) fprintf(f, "-tls_certificate_verified\n");
 234 if (tls_in.cipher)       fprintf(f, "-tls_cipher %s\n", tls_in.cipher);
 235 if (tls_in.peercert)
 236   {
 237   (void) tls_export_cert(big_buffer, big_buffer_size, tls_in.peercert);
 238   fprintf(f, "-tls_peercert %s\n", CS big_buffer);
 239   }
 240 if (tls_in.peerdn)       fprintf(f, "-tls_peerdn %s\n", string_printing(tls_in.peerdn));
 241 if (tls_in.sni)          fprintf(f, "-tls_sni %s\n",    string_printing(tls_in.sni));
 242 if (tls_in.ourcert)
 243   {
 244   (void) tls_export_cert(big_buffer, big_buffer_size, tls_in.ourcert);
 245   fprintf(f, "-tls_ourcert %s\n", CS big_buffer);
 246   }
 247 if (tls_in.ocsp)         fprintf(f, "-tls_ocsp %d\n",   tls_in.ocsp);
 248 #endif
 249
 250 #ifdef SUPPORT_I18N
 251 if (message_smtputf8)
 252   {
 253   fprintf(f, "-smtputf8\n");
 254   if (message_utf8_downconvert)
 255     fprintf(f, "-utf8_%sdowncvt\n", message_utf8_downconvert < 0 ? "opt" : "");
 256   }
 257 #endif
 258
 259 /* Write the dsn flags to the spool header file */
 260 DEBUG(D_deliver) debug_printf("DSN: Write SPOOL :-dsn_envid %s\n", dsn_envid);
 261 if (dsn_envid != NULL) fprintf(f, "-dsn_envid %s\n", dsn_envid);
 262 DEBUG(D_deliver) debug_printf("DSN: Write SPOOL :-dsn_ret %d\n", dsn_ret);
 263 if (dsn_ret != 0) fprintf(f, "-dsn_ret %d\n", dsn_ret);
 264
 265 /* To complete the envelope, write out the tree of non-recipients, followed by
 266 the list of recipients. These won't be disjoint the first time, when no
 267 checking has been done. If a recipient is a "one-time" alias, it is followed by
 268 a space and its parent address number (pno). */
 269
 270 tree_write(tree_nonrecipients, f);
 271 fprintf(f, "%d\n", recipients_count);
 272 for (i = 0; i < recipients_count; i++)
 273   {
 274   recipient_item *r = recipients_list + i;
 275
 276   DEBUG(D_deliver) debug_printf("DSN: Flags :%d\n", r->dsn_flags);
 277
 278   if (r->pno < 0 && r->errors_to == NULL && r->dsn_flags == 0)
 279     fprintf(f, "%s\n", r->address);
 280   else
 281     {
 282     uschar * errors_to = r->errors_to ? r->errors_to : US"";
 283     /* for DSN SUPPORT extend exim 4 spool in a compatible way by
 284     adding new values upfront and add flag 0x02 */
 285     uschar * orcpt = r->orcpt ? r->orcpt : US"";
 286
 287     fprintf(f, "%s %s %d,%d %s %d,%d#3\n", r->address, orcpt, Ustrlen(orcpt),
 288       r->dsn_flags, errors_to, Ustrlen(errors_to), r->pno);
 289     }
 290
 291     DEBUG(D_deliver) debug_printf("DSN: **** SPOOL_OUT - "
 292       "address: |%s| errorsto: |%s| orcpt: |%s| dsn_flags: %d\n",
 293       r->address, r->errors_to, r->orcpt, r->dsn_flags);
 294   }
 295
 296 /* Put a blank line before the headers */
 297
 298 fprintf(f, "\n");
 299
 300 /* Save the size of the file so far so we can subtract it from the final length
 301 to get the actual size of the headers. */
 302
 303 fflush(f);
 304 if (fstat(fd, &statbuf))
 305   return spool_write_error(where, errmsg, US"fstat", tname, f);
 306 size_correction = statbuf.st_size;
 307
 308 /* Finally, write out the message's headers. To make it easier to read them
 309 in again, precede each one with the count of its length. Make the count fixed
 310 length to aid human eyes when debugging and arrange for it not be included in
 311 the size. It is followed by a space for normal headers, a flagging letter for
 312 various other headers, or an asterisk for old headers that have been rewritten.
 313 These are saved as a record for debugging. Don't included them in the message's
 314 size. */
 315
 316 for (h = header_list; h != NULL; h = h->next)
 317   {
 318   fprintf(f, "%03d%c %s", h->slen, h->type, h->text);
 319   size_correction += 5;
 320   if (h->type == '*') size_correction += h->slen;
 321   }
 322
 323 /* Flush and check for any errors while writing */
 324
 325 if (fflush(f) != 0 || ferror(f))
 326   return spool_write_error(where, errmsg, US"write", tname, f);
 327
 328 /* Force the file's contents to be written to disk. Note that fflush()
 329 just pushes it out of C, and fclose() doesn't guarantee to do the write
 330 either. That's just the way Unix works... */
 331
 332 if (EXIMfsync(fileno(f)) < 0)
 333   return spool_write_error(where, errmsg, US"sync", tname, f);
 334
 335 /* Get the size of the file, and close it. */
 336
 337 if (fstat(fd, &statbuf) != 0)
 338   return spool_write_error(where, errmsg, US"fstat", tname, NULL);
 339 if (fclose(f) != 0)
 340   return spool_write_error(where, errmsg, US"close", tname, NULL);
 341
 342 /* Rename the file to its correct name, thereby replacing any previous
 343 incarnation. */
 344
 345 fname = spool_fname(US"input", message_subdir, id, US"-H");
 346 DEBUG(D_receive|D_deliver) debug_printf("Renaming spool header file: %s\n", fname);
 347
 348 if (Urename(tname, fname) < 0)
 349   return spool_write_error(where, errmsg, US"rename", tname, NULL);
 350
 351 /* Linux (and maybe other OS?) does not automatically sync a directory after
 352 an operation like rename. We therefore have to do it forcibly ourselves in
 353 these cases, to make sure the file is actually accessible on disk, as opposed
 354 to just the data being accessible from a file in lost+found. Linux also has
 355 O_DIRECTORY, for opening a directory.
 356
 357 However, it turns out that some file systems (some versions of NFS?) do not
 358 support directory syncing. It seems safe enough to ignore EINVAL to cope with
 359 these cases. One hack on top of another... but that's life. */
 360
 361 #ifdef NEED_SYNC_DIRECTORY
 362
 363 tname = spool_fname(US"input", message_subdir, US".", US"");
 364
 365 # ifndef O_DIRECTORY
 366 #  define O_DIRECTORY 0
 367 # endif
 368
 369 if ((fd = Uopen(tname, O_RDONLY|O_DIRECTORY, 0)) < 0)
 370   return spool_write_error(where, errmsg, US"directory open", fname, NULL);
 371
 372 if (EXIMfsync(fd) < 0 && errno != EINVAL)
 373   return spool_write_error(where, errmsg, US"directory sync", fname, NULL);
 374
 375 if (close(fd) < 0)
 376   return spool_write_error(where, errmsg, US"directory close", fname, NULL);
 377
 378 #endif  /* NEED_SYNC_DIRECTORY */
 379
 380 /* Return the number of characters in the headers, which is the file size, less
 381 the preliminary stuff, less the additional count fields on the headers. */
 382
 383 DEBUG(D_receive) debug_printf("Size of headers = %d\n",
 384   (int)(statbuf.st_size - size_correction));
 385
 386 return statbuf.st_size - size_correction;
 387 }
 388
 389
 390 #ifdef SUPPORT_MOVE_FROZEN_MESSAGES
 391
 392 /************************************************
 393 *              Make a hard link                 *
 394 ************************************************/
 395
 396 /* Used by spool_move_message() below. Note re the use of sprintf(): the value
 397 of spool_directory is checked to ensure that it is less than 200 characters at
 398 start-up time.
 399
 400 Arguments:
 401   dir        base directory name
 402   subdir     subdirectory name
 403   id         message id
 404   suffix     suffix to add to id
 405   from       source directory prefix
 406   to         destination directory prefix
 407   noentok    if TRUE, absence of file is not an error
 408
 409 Returns:     TRUE if all went well
 410              FALSE, having panic logged if not
 411 */
 412
 413 static BOOL
 414 make_link(uschar *dir, uschar *subdir, uschar *id, uschar *suffix, uschar *from,
 415   uschar *to, BOOL noentok)
 416 {
 417 uschar * fname = spool_fname(string_sprintf("%s%s", from, dir), subdir, id, suffix);
 418 uschar * tname = spool_fname(string_sprintf("%s%s", to,   dir), subdir, id, suffix);
 419 if (Ulink(fname, tname) < 0 && (!noentok || errno != ENOENT))
 420   {
 421   log_write(0, LOG_MAIN|LOG_PANIC, "link(\"%s\", \"%s\") failed while moving "
 422     "message: %s", fname, tname, strerror(errno));
 423   return FALSE;
 424   }
 425 return TRUE;
 426 }
 427
 428
 429
 430 /************************************************
 431 *                Break a link                   *
 432 ************************************************/
 433
 434 /* Used by spool_move_message() below. Note re the use of sprintf(): the value
 435 of spool_directory is checked to ensure that it is less than 200 characters at
 436 start-up time.
 437
 438 Arguments:
 439   dir        base directory name
 440   subdir     subdirectory name
 441   id         message id
 442   suffix     suffix to add to id
 443   from       source directory prefix
 444   noentok    if TRUE, absence of file is not an error
 445
 446 Returns:     TRUE if all went well
 447              FALSE, having panic logged if not
 448 */
 449
 450 static BOOL
 451 break_link(uschar *dir, uschar *subdir, uschar *id, uschar *suffix, uschar *from,
 452   BOOL noentok)
 453 {
 454 uschar * fname = spool_fname(string_sprintf("%s%s", from, dir), subdir, id, suffix);
 455 if (Uunlink(fname) < 0 && (!noentok || errno != ENOENT))
 456   {
 457   log_write(0, LOG_MAIN|LOG_PANIC, "unlink(\"%s\") failed while moving "
 458     "message: %s", fname, strerror(errno));
 459   return FALSE;
 460   }
 461 return TRUE;
 462 }
 463
 464
 465
 466 /************************************************
 467 *            Move message files                 *
 468 ************************************************/
 469
 470 /* Move the files for a message (-H, -D, and msglog) from one directory (or
 471 hierarchy) to another. It is assume that there is no -J file in existence when
 472 this is done. At present, this is used only when move_frozen_messages is set,
 473 so compile it only when that support is configured.
 474
 475 Arguments:
 476   id          the id of the message to be delivered
 477   subdir      the subdirectory name, or an empty string
 478   from        a prefix for "input" or "msglog" for where the message is now
 479   to          a prefix for "input" or "msglog" for where the message is to go
 480
 481 Returns:      TRUE if all is well
 482               FALSE if not, with error logged in panic and main logs
 483 */
 484
 485 BOOL
 486 spool_move_message(uschar *id, uschar *subdir, uschar *from, uschar *to)
 487 {
 488 /* Create any output directories that do not exist. */
 489
 490 (void) directory_make(spool_directory,
 491   spool_sname(string_sprintf("%sinput", to), subdir),
 492   INPUT_DIRECTORY_MODE, TRUE);
 493 (void) directory_make(spool_directory,
 494   spool_sname(string_sprintf("%smsglog", to), subdir),
 495   INPUT_DIRECTORY_MODE, TRUE);
 496
 497 /* Move the message by first creating new hard links for all the files, and
 498 then removing the old links. When moving messages onto the main spool, the -H
 499 file should be set up last, because that's the one that tells Exim there is a
 500 message to be delivered, so we create its new link last and remove its old link
 501 first. Programs that look at the alternate directories should follow the same
 502 rule of waiting for a -H file before doing anything. When moving messages off
 503 the mail spool, the -D file should be open and locked at the time, thus keeping
 504 Exim's hands off. */
 505
 506 if (!make_link(US"msglog", subdir, id, US"", from, to, TRUE) ||
 507     !make_link(US"input",  subdir, id, US"-D", from, to, FALSE) ||
 508     !make_link(US"input",  subdir, id, US"-H", from, to, FALSE))
 509   return FALSE;
 510
 511 if (!break_link(US"input",  subdir, id, US"-H", from, FALSE) ||
 512     !break_link(US"input",  subdir, id, US"-D", from, FALSE) ||
 513     !break_link(US"msglog", subdir, id, US"", from, TRUE))
 514   return FALSE;
 515
 516 log_write(0, LOG_MAIN, "moved from %sinput, %smsglog to %sinput, %smsglog",
 517    from, from, to, to);
 518
 519 return TRUE;
 520 }
 521
 522 #endif
 523
 524 /* End of spool_out.c */
 525 /* vi: aw ai sw=2
 526 */