src/src/spool_out.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2018 */
   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 (exim_fchown(fd, exim_uid, exim_gid, temp_name) || 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 size_correction;
 132 FILE * fp;
 133 struct stat statbuf;
 134 uschar * tname;
 135 uschar * fname;
 136
 137 tname = spool_fname(US"input", message_subdir, US"hdr.", message_id);
 138
 139 if ((fd = spool_open_temp(tname)) < 0)
 140   return spool_write_error(where, errmsg, US"open", NULL, NULL);
 141 fp = fdopen(fd, "wb");
 142 DEBUG(D_receive|D_deliver) debug_printf("Writing spool header file: %s\n", tname);
 143
 144 /* We now have an open file to which the header data is to be written. Start
 145 with the file's leaf name, to make the file self-identifying. Continue with the
 146 identity of the submitting user, followed by the sender's address. The sender's
 147 address is enclosed in <> because it might be the null address. Then write the
 148 received time and the number of warning messages that have been sent. */
 149
 150 fprintf(fp, "%s-H\n", message_id);
 151 fprintf(fp, "%.63s %ld %ld\n", originator_login, (long int)originator_uid,
 152   (long int)originator_gid);
 153 fprintf(fp, "<%s>\n", sender_address);
 154 fprintf(fp, "%d %d\n", (int)received_time.tv_sec, warning_count);
 155
 156 fprintf(fp, "-received_time_usec .%06d\n", (int)received_time.tv_usec);
 157
 158 /* If there is information about a sending host, remember it. The HELO
 159 data can be set for local SMTP as well as remote. */
 160
 161 if (sender_helo_name)
 162   fprintf(fp, "-helo_name %s\n", sender_helo_name);
 163
 164 if (sender_host_address)
 165   {
 166   fprintf(fp, "-host_address %s.%d\n", sender_host_address, sender_host_port);
 167   if (sender_host_name)
 168     fprintf(fp, "-host_name %s\n", sender_host_name);
 169   if (sender_host_authenticated)
 170     fprintf(fp, "-host_auth %s\n", sender_host_authenticated);
 171   }
 172
 173 /* Also about the interface a message came in on */
 174
 175 if (interface_address)
 176   fprintf(fp, "-interface_address %s.%d\n", interface_address, interface_port);
 177
 178 if (smtp_active_hostname != primary_hostname)
 179   fprintf(fp, "-active_hostname %s\n", smtp_active_hostname);
 180
 181 /* Likewise for any ident information; for local messages this is
 182 likely to be the same as originator_login, but will be different if
 183 the originator was root, forcing a different ident. */
 184
 185 if (sender_ident) fprintf(fp, "-ident %s\n", sender_ident);
 186
 187 /* Ditto for the received protocol */
 188
 189 if (received_protocol)
 190   fprintf(fp, "-received_protocol %s\n", received_protocol);
 191
 192 /* Preserve any ACL variables that are set. */
 193
 194 tree_walk(acl_var_c, &acl_var_write, fp);
 195 tree_walk(acl_var_m, &acl_var_write, fp);
 196
 197 /* Now any other data that needs to be remembered. */
 198
 199 if (f.spool_file_wireformat)
 200   fprintf(fp, "-spool_file_wireformat\n");
 201 else
 202   fprintf(fp, "-body_linecount %d\n", body_linecount);
 203 fprintf(fp, "-max_received_linelength %d\n", max_received_linelength);
 204
 205 if (body_zerocount > 0) fprintf(fp, "-body_zerocount %d\n", body_zerocount);
 206
 207 if (authenticated_id)
 208   fprintf(fp, "-auth_id %s\n", authenticated_id);
 209 if (authenticated_sender)
 210   fprintf(fp, "-auth_sender %s\n", authenticated_sender);
 211
 212 if (f.allow_unqualified_recipient) fprintf(fp, "-allow_unqualified_recipient\n");
 213 if (f.allow_unqualified_sender) fprintf(fp, "-allow_unqualified_sender\n");
 214 if (f.deliver_firsttime) fprintf(fp, "-deliver_firsttime\n");
 215 if (f.deliver_freeze) fprintf(fp, "-frozen " TIME_T_FMT "\n", deliver_frozen_at);
 216 if (f.dont_deliver) fprintf(fp, "-N\n");
 217 if (host_lookup_deferred) fprintf(fp, "-host_lookup_deferred\n");
 218 if (host_lookup_failed) fprintf(fp, "-host_lookup_failed\n");
 219 if (f.sender_local) fprintf(fp, "-local\n");
 220 if (f.local_error_message) fprintf(fp, "-localerror\n");
 221 #ifdef HAVE_LOCAL_SCAN
 222 if (local_scan_data) fprintf(fp, "-local_scan %s\n", local_scan_data);
 223 #endif
 224 #ifdef WITH_CONTENT_SCAN
 225 if (spam_bar)       fprintf(fp,"-spam_bar %s\n",       spam_bar);
 226 if (spam_score)     fprintf(fp,"-spam_score %s\n",     spam_score);
 227 if (spam_score_int) fprintf(fp,"-spam_score_int %s\n", spam_score_int);
 228 #endif
 229 if (f.deliver_manual_thaw) fprintf(fp, "-manual_thaw\n");
 230 if (f.sender_set_untrusted) fprintf(fp, "-sender_set_untrusted\n");
 231
 232 #ifdef EXPERIMENTAL_BRIGHTMAIL
 233 if (bmi_verdicts) fprintf(fp, "-bmi_verdicts %s\n", bmi_verdicts);
 234 #endif
 235
 236 #ifdef SUPPORT_TLS
 237 if (tls_in.certificate_verified) fprintf(fp, "-tls_certificate_verified\n");
 238 if (tls_in.cipher)       fprintf(fp, "-tls_cipher %s\n", tls_in.cipher);
 239 if (tls_in.peercert)
 240   {
 241   (void) tls_export_cert(big_buffer, big_buffer_size, tls_in.peercert);
 242   fprintf(fp, "-tls_peercert %s\n", CS big_buffer);
 243   }
 244 if (tls_in.peerdn)       fprintf(fp, "-tls_peerdn %s\n", string_printing(tls_in.peerdn));
 245 if (tls_in.sni)          fprintf(fp, "-tls_sni %s\n",    string_printing(tls_in.sni));
 246 if (tls_in.ourcert)
 247   {
 248   (void) tls_export_cert(big_buffer, big_buffer_size, tls_in.ourcert);
 249   fprintf(fp, "-tls_ourcert %s\n", CS big_buffer);
 250   }
 251 if (tls_in.ocsp)         fprintf(fp, "-tls_ocsp %d\n",   tls_in.ocsp);
 252 #endif
 253
 254 #ifdef SUPPORT_I18N
 255 if (message_smtputf8)
 256   {
 257   fprintf(fp, "-smtputf8\n");
 258   if (message_utf8_downconvert)
 259     fprintf(fp, "-utf8_%sdowncvt\n", message_utf8_downconvert < 0 ? "opt" : "");
 260   }
 261 #endif
 262
 263 /* Write the dsn flags to the spool header file */
 264 DEBUG(D_deliver) debug_printf("DSN: Write SPOOL :-dsn_envid %s\n", dsn_envid);
 265 if (dsn_envid) fprintf(fp, "-dsn_envid %s\n", dsn_envid);
 266 DEBUG(D_deliver) debug_printf("DSN: Write SPOOL :-dsn_ret %d\n", dsn_ret);
 267 if (dsn_ret) fprintf(fp, "-dsn_ret %d\n", dsn_ret);
 268
 269 /* To complete the envelope, write out the tree of non-recipients, followed by
 270 the list of recipients. These won't be disjoint the first time, when no
 271 checking has been done. If a recipient is a "one-time" alias, it is followed by
 272 a space and its parent address number (pno). */
 273
 274 tree_write(tree_nonrecipients, fp);
 275 fprintf(fp, "%d\n", recipients_count);
 276 for (int i = 0; i < recipients_count; i++)
 277   {
 278   recipient_item *r = recipients_list + i;
 279
 280   DEBUG(D_deliver) debug_printf("DSN: Flags :%d\n", r->dsn_flags);
 281
 282   if (r->pno < 0 && r->errors_to == NULL && r->dsn_flags == 0)
 283     fprintf(fp, "%s\n", r->address);
 284   else
 285     {
 286     uschar * errors_to = r->errors_to ? r->errors_to : US"";
 287     /* for DSN SUPPORT extend exim 4 spool in a compatible way by
 288     adding new values upfront and add flag 0x02 */
 289     uschar * orcpt = r->orcpt ? r->orcpt : US"";
 290
 291     fprintf(fp, "%s %s %d,%d %s %d,%d#3\n", r->address, orcpt, Ustrlen(orcpt),
 292       r->dsn_flags, errors_to, Ustrlen(errors_to), r->pno);
 293     }
 294
 295     DEBUG(D_deliver) debug_printf("DSN: **** SPOOL_OUT - "
 296       "address: |%s| errorsto: |%s| orcpt: |%s| dsn_flags: %d\n",
 297       r->address, r->errors_to, r->orcpt, r->dsn_flags);
 298   }
 299
 300 /* Put a blank line before the headers */
 301
 302 fprintf(fp, "\n");
 303
 304 /* Save the size of the file so far so we can subtract it from the final length
 305 to get the actual size of the headers. */
 306
 307 fflush(fp);
 308 if (fstat(fd, &statbuf))
 309   return spool_write_error(where, errmsg, US"fstat", tname, fp);
 310 size_correction = statbuf.st_size;
 311
 312 /* Finally, write out the message's headers. To make it easier to read them
 313 in again, precede each one with the count of its length. Make the count fixed
 314 length to aid human eyes when debugging and arrange for it not be included in
 315 the size. It is followed by a space for normal headers, a flagging letter for
 316 various other headers, or an asterisk for old headers that have been rewritten.
 317 These are saved as a record for debugging. Don't included them in the message's
 318 size. */
 319
 320 for (header_line * h = header_list; h; h = h->next)
 321   {
 322   fprintf(fp, "%03d%c %s", h->slen, h->type, h->text);
 323   size_correction += 5;
 324   if (h->type == '*') size_correction += h->slen;
 325   }
 326
 327 /* Flush and check for any errors while writing */
 328
 329 if (fflush(fp) != 0 || ferror(fp))
 330   return spool_write_error(where, errmsg, US"write", tname, fp);
 331
 332 /* Force the file's contents to be written to disk. Note that fflush()
 333 just pushes it out of C, and fclose() doesn't guarantee to do the write
 334 either. That's just the way Unix works... */
 335
 336 if (EXIMfsync(fileno(fp)) < 0)
 337   return spool_write_error(where, errmsg, US"sync", tname, fp);
 338
 339 /* Get the size of the file, and close it. */
 340
 341 if (fstat(fd, &statbuf) != 0)
 342   return spool_write_error(where, errmsg, US"fstat", tname, NULL);
 343 if (fclose(fp) != 0)
 344   return spool_write_error(where, errmsg, US"close", tname, NULL);
 345
 346 /* Rename the file to its correct name, thereby replacing any previous
 347 incarnation. */
 348
 349 fname = spool_fname(US"input", message_subdir, id, US"-H");
 350 DEBUG(D_receive|D_deliver) debug_printf("Renaming spool header file: %s\n", fname);
 351
 352 if (Urename(tname, fname) < 0)
 353   return spool_write_error(where, errmsg, US"rename", tname, NULL);
 354
 355 /* Linux (and maybe other OS?) does not automatically sync a directory after
 356 an operation like rename. We therefore have to do it forcibly ourselves in
 357 these cases, to make sure the file is actually accessible on disk, as opposed
 358 to just the data being accessible from a file in lost+found. Linux also has
 359 O_DIRECTORY, for opening a directory.
 360
 361 However, it turns out that some file systems (some versions of NFS?) do not
 362 support directory syncing. It seems safe enough to ignore EINVAL to cope with
 363 these cases. One hack on top of another... but that's life. */
 364
 365 #ifdef NEED_SYNC_DIRECTORY
 366
 367 tname = spool_fname(US"input", message_subdir, US".", US"");
 368
 369 # ifndef O_DIRECTORY
 370 #  define O_DIRECTORY 0
 371 # endif
 372
 373 if ((fd = Uopen(tname, O_RDONLY|O_DIRECTORY, 0)) < 0)
 374   return spool_write_error(where, errmsg, US"directory open", fname, NULL);
 375
 376 if (EXIMfsync(fd) < 0 && errno != EINVAL)
 377   return spool_write_error(where, errmsg, US"directory sync", fname, NULL);
 378
 379 if (close(fd) < 0)
 380   return spool_write_error(where, errmsg, US"directory close", fname, NULL);
 381
 382 #endif  /* NEED_SYNC_DIRECTORY */
 383
 384 /* Return the number of characters in the headers, which is the file size, less
 385 the preliminary stuff, less the additional count fields on the headers. */
 386
 387 DEBUG(D_receive) debug_printf("Size of headers = %d\n",
 388   (int)(statbuf.st_size - size_correction));
 389
 390 return statbuf.st_size - size_correction;
 391 }
 392
 393
 394 #ifdef SUPPORT_MOVE_FROZEN_MESSAGES
 395
 396 /************************************************
 397 *              Make a hard link                 *
 398 ************************************************/
 399
 400 /* Used by spool_move_message() below. Note re the use of sprintf(): the value
 401 of spool_directory is checked to ensure that it is less than 200 characters at
 402 start-up time.
 403
 404 Arguments:
 405   dir        base directory name
 406   subdir     subdirectory name
 407   id         message id
 408   suffix     suffix to add to id
 409   from       source directory prefix
 410   to         destination directory prefix
 411   noentok    if TRUE, absence of file is not an error
 412
 413 Returns:     TRUE if all went well
 414              FALSE, having panic logged if not
 415 */
 416
 417 static BOOL
 418 make_link(uschar *dir, uschar *subdir, uschar *id, uschar *suffix, uschar *from,
 419   uschar *to, BOOL noentok)
 420 {
 421 uschar * fname = spool_fname(string_sprintf("%s%s", from, dir), subdir, id, suffix);
 422 uschar * tname = spool_fname(string_sprintf("%s%s", to,   dir), subdir, id, suffix);
 423 if (Ulink(fname, tname) < 0 && (!noentok || errno != ENOENT))
 424   {
 425   log_write(0, LOG_MAIN|LOG_PANIC, "link(\"%s\", \"%s\") failed while moving "
 426     "message: %s", fname, tname, strerror(errno));
 427   return FALSE;
 428   }
 429 return TRUE;
 430 }
 431
 432
 433
 434 /************************************************
 435 *                Break a link                   *
 436 ************************************************/
 437
 438 /* Used by spool_move_message() below. Note re the use of sprintf(): the value
 439 of spool_directory is checked to ensure that it is less than 200 characters at
 440 start-up time.
 441
 442 Arguments:
 443   dir        base directory name
 444   subdir     subdirectory name
 445   id         message id
 446   suffix     suffix to add to id
 447   from       source directory prefix
 448   noentok    if TRUE, absence of file is not an error
 449
 450 Returns:     TRUE if all went well
 451              FALSE, having panic logged if not
 452 */
 453
 454 static BOOL
 455 break_link(uschar *dir, uschar *subdir, uschar *id, uschar *suffix, uschar *from,
 456   BOOL noentok)
 457 {
 458 uschar * fname = spool_fname(string_sprintf("%s%s", from, dir), subdir, id, suffix);
 459 if (Uunlink(fname) < 0 && (!noentok || errno != ENOENT))
 460   {
 461   log_write(0, LOG_MAIN|LOG_PANIC, "unlink(\"%s\") failed while moving "
 462     "message: %s", fname, strerror(errno));
 463   return FALSE;
 464   }
 465 return TRUE;
 466 }
 467
 468
 469
 470 /************************************************
 471 *            Move message files                 *
 472 ************************************************/
 473
 474 /* Move the files for a message (-H, -D, and msglog) from one directory (or
 475 hierarchy) to another. It is assume that there is no -J file in existence when
 476 this is done. At present, this is used only when move_frozen_messages is set,
 477 so compile it only when that support is configured.
 478
 479 Arguments:
 480   id          the id of the message to be delivered
 481   subdir      the subdirectory name, or an empty string
 482   from        a prefix for "input" or "msglog" for where the message is now
 483   to          a prefix for "input" or "msglog" for where the message is to go
 484
 485 Returns:      TRUE if all is well
 486               FALSE if not, with error logged in panic and main logs
 487 */
 488
 489 BOOL
 490 spool_move_message(uschar *id, uschar *subdir, uschar *from, uschar *to)
 491 {
 492 /* Create any output directories that do not exist. */
 493
 494 (void) directory_make(spool_directory,
 495   spool_sname(string_sprintf("%sinput", to), subdir),
 496   INPUT_DIRECTORY_MODE, TRUE);
 497 (void) directory_make(spool_directory,
 498   spool_sname(string_sprintf("%smsglog", to), subdir),
 499   INPUT_DIRECTORY_MODE, TRUE);
 500
 501 /* Move the message by first creating new hard links for all the files, and
 502 then removing the old links. When moving messages onto the main spool, the -H
 503 file should be set up last, because that's the one that tells Exim there is a
 504 message to be delivered, so we create its new link last and remove its old link
 505 first. Programs that look at the alternate directories should follow the same
 506 rule of waiting for a -H file before doing anything. When moving messages off
 507 the mail spool, the -D file should be open and locked at the time, thus keeping
 508 Exim's hands off. */
 509
 510 if (!make_link(US"msglog", subdir, id, US"", from, to, TRUE) ||
 511     !make_link(US"input",  subdir, id, US"-D", from, to, FALSE) ||
 512     !make_link(US"input",  subdir, id, US"-H", from, to, FALSE))
 513   return FALSE;
 514
 515 if (!break_link(US"input",  subdir, id, US"-H", from, FALSE) ||
 516     !break_link(US"input",  subdir, id, US"-D", from, FALSE) ||
 517     !break_link(US"msglog", subdir, id, US"", from, TRUE))
 518   return FALSE;
 519
 520 log_write(0, LOG_MAIN, "moved from %sinput, %smsglog to %sinput, %smsglog",
 521    from, from, to, to);
 522
 523 return TRUE;
 524 }
 525
 526 #endif
 527
 528 /* End of spool_out.c */
 529 /* vi: aw ai sw=2
 530 */