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 (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 size_correction;
 132 FILE * fp;
 133 struct stat statbuf;
 134 uschar * tname;
 135 uschar * fname;
 136
 137 tname = spool_fname(US"input", message_subdir,
 138                     string_sprintf("hdr.%d", (int)getpid()), US"");
 139
 140 if ((fd = spool_open_temp(tname)) < 0)
 141   return spool_write_error(where, errmsg, US"open", NULL, NULL);
 142 fp = fdopen(fd, "wb");
 143 DEBUG(D_receive|D_deliver) debug_printf("Writing spool header file: %s\n", tname);
 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(fp, "%s-H\n", message_id);
 152 fprintf(fp, "%.63s %ld %ld\n", originator_login, (long int)originator_uid,
 153   (long int)originator_gid);
 154 fprintf(fp, "<%s>\n", sender_address);
 155 fprintf(fp, "%d %d\n", (int)received_time.tv_sec, warning_count);
 156
 157 fprintf(fp, "-received_time_usec .%06d\n", (int)received_time.tv_usec);
 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)
 163   fprintf(fp, "-helo_name %s\n", sender_helo_name);
 164
 165 if (sender_host_address)
 166   {
 167   fprintf(fp, "-host_address %s.%d\n", sender_host_address, sender_host_port);
 168   if (sender_host_name)
 169     fprintf(fp, "-host_name %s\n", sender_host_name);
 170   if (sender_host_authenticated)
 171     fprintf(fp, "-host_auth %s\n", sender_host_authenticated);
 172   }
 173
 174 /* Also about the interface a message came in on */
 175
 176 if (interface_address)
 177   fprintf(fp, "-interface_address %s.%d\n", interface_address, interface_port);
 178
 179 if (smtp_active_hostname != primary_hostname)
 180   fprintf(fp, "-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) fprintf(fp, "-ident %s\n", sender_ident);
 187
 188 /* Ditto for the received protocol */
 189
 190 if (received_protocol)
 191   fprintf(fp, "-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, fp);
 196 tree_walk(acl_var_m, &acl_var_write, fp);
 197
 198 /* Now any other data that needs to be remembered. */
 199
 200 if (f.spool_file_wireformat)
 201   fprintf(fp, "-spool_file_wireformat\n");
 202 else
 203   fprintf(fp, "-body_linecount %d\n", body_linecount);
 204 fprintf(fp, "-max_received_linelength %d\n", max_received_linelength);
 205
 206 if (body_zerocount > 0) fprintf(fp, "-body_zerocount %d\n", body_zerocount);
 207
 208 if (authenticated_id)
 209   fprintf(fp, "-auth_id %s\n", authenticated_id);
 210 if (authenticated_sender)
 211   fprintf(fp, "-auth_sender %s\n", authenticated_sender);
 212
 213 if (f.allow_unqualified_recipient) fprintf(fp, "-allow_unqualified_recipient\n");
 214 if (f.allow_unqualified_sender) fprintf(fp, "-allow_unqualified_sender\n");
 215 if (f.deliver_firsttime) fprintf(fp, "-deliver_firsttime\n");
 216 if (f.deliver_freeze) fprintf(fp, "-frozen " TIME_T_FMT "\n", deliver_frozen_at);
 217 if (f.dont_deliver) fprintf(fp, "-N\n");
 218 if (host_lookup_deferred) fprintf(fp, "-host_lookup_deferred\n");
 219 if (host_lookup_failed) fprintf(fp, "-host_lookup_failed\n");
 220 if (f.sender_local) fprintf(fp, "-local\n");
 221 if (f.local_error_message) fprintf(fp, "-localerror\n");
 222 #ifdef HAVE_LOCAL_SCAN
 223 if (local_scan_data) fprintf(fp, "-local_scan %s\n", local_scan_data);
 224 #endif
 225 #ifdef WITH_CONTENT_SCAN
 226 if (spam_bar)       fprintf(fp,"-spam_bar %s\n",       spam_bar);
 227 if (spam_score)     fprintf(fp,"-spam_score %s\n",     spam_score);
 228 if (spam_score_int) fprintf(fp,"-spam_score_int %s\n", spam_score_int);
 229 #endif
 230 if (f.deliver_manual_thaw) fprintf(fp, "-manual_thaw\n");
 231 if (f.sender_set_untrusted) fprintf(fp, "-sender_set_untrusted\n");
 232
 233 #ifdef EXPERIMENTAL_BRIGHTMAIL
 234 if (bmi_verdicts) fprintf(fp, "-bmi_verdicts %s\n", bmi_verdicts);
 235 #endif
 236
 237 #ifdef SUPPORT_TLS
 238 if (tls_in.certificate_verified) fprintf(fp, "-tls_certificate_verified\n");
 239 if (tls_in.cipher)       fprintf(fp, "-tls_cipher %s\n", tls_in.cipher);
 240 if (tls_in.peercert)
 241   {
 242   (void) tls_export_cert(big_buffer, big_buffer_size, tls_in.peercert);
 243   fprintf(fp, "-tls_peercert %s\n", CS big_buffer);
 244   }
 245 if (tls_in.peerdn)       fprintf(fp, "-tls_peerdn %s\n", string_printing(tls_in.peerdn));
 246 if (tls_in.sni)          fprintf(fp, "-tls_sni %s\n",    string_printing(tls_in.sni));
 247 if (tls_in.ourcert)
 248   {
 249   (void) tls_export_cert(big_buffer, big_buffer_size, tls_in.ourcert);
 250   fprintf(fp, "-tls_ourcert %s\n", CS big_buffer);
 251   }
 252 if (tls_in.ocsp)         fprintf(fp, "-tls_ocsp %d\n",   tls_in.ocsp);
 253
 254 # ifdef EXPERIMENTAL_REQUIRETLS
 255 if (tls_requiretls)      fprintf(fp, "-tls_requiretls 0x%x\n", tls_requiretls);
 256 # endif
 257 #endif
 258
 259 #ifdef SUPPORT_I18N
 260 if (message_smtputf8)
 261   {
 262   fprintf(fp, "-smtputf8\n");
 263   if (message_utf8_downconvert)
 264     fprintf(fp, "-utf8_%sdowncvt\n", message_utf8_downconvert < 0 ? "opt" : "");
 265   }
 266 #endif
 267
 268 /* Write the dsn flags to the spool header file */
 269 DEBUG(D_deliver) debug_printf("DSN: Write SPOOL :-dsn_envid %s\n", dsn_envid);
 270 if (dsn_envid) fprintf(fp, "-dsn_envid %s\n", dsn_envid);
 271 DEBUG(D_deliver) debug_printf("DSN: Write SPOOL :-dsn_ret %d\n", dsn_ret);
 272 if (dsn_ret) fprintf(fp, "-dsn_ret %d\n", dsn_ret);
 273
 274 /* To complete the envelope, write out the tree of non-recipients, followed by
 275 the list of recipients. These won't be disjoint the first time, when no
 276 checking has been done. If a recipient is a "one-time" alias, it is followed by
 277 a space and its parent address number (pno). */
 278
 279 tree_write(tree_nonrecipients, fp);
 280 fprintf(fp, "%d\n", recipients_count);
 281 for (int i = 0; i < recipients_count; i++)
 282   {
 283   recipient_item *r = recipients_list + i;
 284
 285   DEBUG(D_deliver) debug_printf("DSN: Flags :%d\n", r->dsn_flags);
 286
 287   if (r->pno < 0 && r->errors_to == NULL && r->dsn_flags == 0)
 288     fprintf(fp, "%s\n", r->address);
 289   else
 290     {
 291     uschar * errors_to = r->errors_to ? r->errors_to : US"";
 292     /* for DSN SUPPORT extend exim 4 spool in a compatible way by
 293     adding new values upfront and add flag 0x02 */
 294     uschar * orcpt = r->orcpt ? r->orcpt : US"";
 295
 296     fprintf(fp, "%s %s %d,%d %s %d,%d#3\n", r->address, orcpt, Ustrlen(orcpt),
 297       r->dsn_flags, errors_to, Ustrlen(errors_to), r->pno);
 298     }
 299
 300     DEBUG(D_deliver) debug_printf("DSN: **** SPOOL_OUT - "
 301       "address: |%s| errorsto: |%s| orcpt: |%s| dsn_flags: %d\n",
 302       r->address, r->errors_to, r->orcpt, r->dsn_flags);
 303   }
 304
 305 /* Put a blank line before the headers */
 306
 307 fprintf(fp, "\n");
 308
 309 /* Save the size of the file so far so we can subtract it from the final length
 310 to get the actual size of the headers. */
 311
 312 fflush(fp);
 313 if (fstat(fd, &statbuf))
 314   return spool_write_error(where, errmsg, US"fstat", tname, fp);
 315 size_correction = statbuf.st_size;
 316
 317 /* Finally, write out the message's headers. To make it easier to read them
 318 in again, precede each one with the count of its length. Make the count fixed
 319 length to aid human eyes when debugging and arrange for it not be included in
 320 the size. It is followed by a space for normal headers, a flagging letter for
 321 various other headers, or an asterisk for old headers that have been rewritten.
 322 These are saved as a record for debugging. Don't included them in the message's
 323 size. */
 324
 325 for (header_line * h = header_list; h; h = h->next)
 326   {
 327   fprintf(fp, "%03d%c %s", h->slen, h->type, h->text);
 328   size_correction += 5;
 329   if (h->type == '*') size_correction += h->slen;
 330   }
 331
 332 /* Flush and check for any errors while writing */
 333
 334 if (fflush(fp) != 0 || ferror(fp))
 335   return spool_write_error(where, errmsg, US"write", tname, fp);
 336
 337 /* Force the file's contents to be written to disk. Note that fflush()
 338 just pushes it out of C, and fclose() doesn't guarantee to do the write
 339 either. That's just the way Unix works... */
 340
 341 if (EXIMfsync(fileno(fp)) < 0)
 342   return spool_write_error(where, errmsg, US"sync", tname, fp);
 343
 344 /* Get the size of the file, and close it. */
 345
 346 if (fstat(fd, &statbuf) != 0)
 347   return spool_write_error(where, errmsg, US"fstat", tname, NULL);
 348 if (fclose(fp) != 0)
 349   return spool_write_error(where, errmsg, US"close", tname, NULL);
 350
 351 /* Rename the file to its correct name, thereby replacing any previous
 352 incarnation. */
 353
 354 fname = spool_fname(US"input", message_subdir, id, US"-H");
 355 DEBUG(D_receive|D_deliver) debug_printf("Renaming spool header file: %s\n", fname);
 356
 357 if (Urename(tname, fname) < 0)
 358   return spool_write_error(where, errmsg, US"rename", tname, NULL);
 359
 360 /* Linux (and maybe other OS?) does not automatically sync a directory after
 361 an operation like rename. We therefore have to do it forcibly ourselves in
 362 these cases, to make sure the file is actually accessible on disk, as opposed
 363 to just the data being accessible from a file in lost+found. Linux also has
 364 O_DIRECTORY, for opening a directory.
 365
 366 However, it turns out that some file systems (some versions of NFS?) do not
 367 support directory syncing. It seems safe enough to ignore EINVAL to cope with
 368 these cases. One hack on top of another... but that's life. */
 369
 370 #ifdef NEED_SYNC_DIRECTORY
 371
 372 tname = spool_fname(US"input", message_subdir, US".", US"");
 373
 374 # ifndef O_DIRECTORY
 375 #  define O_DIRECTORY 0
 376 # endif
 377
 378 if ((fd = Uopen(tname, O_RDONLY|O_DIRECTORY, 0)) < 0)
 379   return spool_write_error(where, errmsg, US"directory open", fname, NULL);
 380
 381 if (EXIMfsync(fd) < 0 && errno != EINVAL)
 382   return spool_write_error(where, errmsg, US"directory sync", fname, NULL);
 383
 384 if (close(fd) < 0)
 385   return spool_write_error(where, errmsg, US"directory close", fname, NULL);
 386
 387 #endif  /* NEED_SYNC_DIRECTORY */
 388
 389 /* Return the number of characters in the headers, which is the file size, less
 390 the preliminary stuff, less the additional count fields on the headers. */
 391
 392 DEBUG(D_receive) debug_printf("Size of headers = %d\n",
 393   (int)(statbuf.st_size - size_correction));
 394
 395 return statbuf.st_size - size_correction;
 396 }
 397
 398
 399 #ifdef SUPPORT_MOVE_FROZEN_MESSAGES
 400
 401 /************************************************
 402 *              Make a hard link                 *
 403 ************************************************/
 404
 405 /* Used by spool_move_message() below. Note re the use of sprintf(): the value
 406 of spool_directory is checked to ensure that it is less than 200 characters at
 407 start-up time.
 408
 409 Arguments:
 410   dir        base directory name
 411   subdir     subdirectory name
 412   id         message id
 413   suffix     suffix to add to id
 414   from       source directory prefix
 415   to         destination directory prefix
 416   noentok    if TRUE, absence of file is not an error
 417
 418 Returns:     TRUE if all went well
 419              FALSE, having panic logged if not
 420 */
 421
 422 static BOOL
 423 make_link(uschar *dir, uschar *subdir, uschar *id, uschar *suffix, uschar *from,
 424   uschar *to, BOOL noentok)
 425 {
 426 uschar * fname = spool_fname(string_sprintf("%s%s", from, dir), subdir, id, suffix);
 427 uschar * tname = spool_fname(string_sprintf("%s%s", to,   dir), subdir, id, suffix);
 428 if (Ulink(fname, tname) < 0 && (!noentok || errno != ENOENT))
 429   {
 430   log_write(0, LOG_MAIN|LOG_PANIC, "link(\"%s\", \"%s\") failed while moving "
 431     "message: %s", fname, tname, strerror(errno));
 432   return FALSE;
 433   }
 434 return TRUE;
 435 }
 436
 437
 438
 439 /************************************************
 440 *                Break a link                   *
 441 ************************************************/
 442
 443 /* Used by spool_move_message() below. Note re the use of sprintf(): the value
 444 of spool_directory is checked to ensure that it is less than 200 characters at
 445 start-up time.
 446
 447 Arguments:
 448   dir        base directory name
 449   subdir     subdirectory name
 450   id         message id
 451   suffix     suffix to add to id
 452   from       source directory prefix
 453   noentok    if TRUE, absence of file is not an error
 454
 455 Returns:     TRUE if all went well
 456              FALSE, having panic logged if not
 457 */
 458
 459 static BOOL
 460 break_link(uschar *dir, uschar *subdir, uschar *id, uschar *suffix, uschar *from,
 461   BOOL noentok)
 462 {
 463 uschar * fname = spool_fname(string_sprintf("%s%s", from, dir), subdir, id, suffix);
 464 if (Uunlink(fname) < 0 && (!noentok || errno != ENOENT))
 465   {
 466   log_write(0, LOG_MAIN|LOG_PANIC, "unlink(\"%s\") failed while moving "
 467     "message: %s", fname, strerror(errno));
 468   return FALSE;
 469   }
 470 return TRUE;
 471 }
 472
 473
 474
 475 /************************************************
 476 *            Move message files                 *
 477 ************************************************/
 478
 479 /* Move the files for a message (-H, -D, and msglog) from one directory (or
 480 hierarchy) to another. It is assume that there is no -J file in existence when
 481 this is done. At present, this is used only when move_frozen_messages is set,
 482 so compile it only when that support is configured.
 483
 484 Arguments:
 485   id          the id of the message to be delivered
 486   subdir      the subdirectory name, or an empty string
 487   from        a prefix for "input" or "msglog" for where the message is now
 488   to          a prefix for "input" or "msglog" for where the message is to go
 489
 490 Returns:      TRUE if all is well
 491               FALSE if not, with error logged in panic and main logs
 492 */
 493
 494 BOOL
 495 spool_move_message(uschar *id, uschar *subdir, uschar *from, uschar *to)
 496 {
 497 /* Create any output directories that do not exist. */
 498
 499 (void) directory_make(spool_directory,
 500   spool_sname(string_sprintf("%sinput", to), subdir),
 501   INPUT_DIRECTORY_MODE, TRUE);
 502 (void) directory_make(spool_directory,
 503   spool_sname(string_sprintf("%smsglog", to), subdir),
 504   INPUT_DIRECTORY_MODE, TRUE);
 505
 506 /* Move the message by first creating new hard links for all the files, and
 507 then removing the old links. When moving messages onto the main spool, the -H
 508 file should be set up last, because that's the one that tells Exim there is a
 509 message to be delivered, so we create its new link last and remove its old link
 510 first. Programs that look at the alternate directories should follow the same
 511 rule of waiting for a -H file before doing anything. When moving messages off
 512 the mail spool, the -D file should be open and locked at the time, thus keeping
 513 Exim's hands off. */
 514
 515 if (!make_link(US"msglog", subdir, id, US"", from, to, TRUE) ||
 516     !make_link(US"input",  subdir, id, US"-D", from, to, FALSE) ||
 517     !make_link(US"input",  subdir, id, US"-H", from, to, FALSE))
 518   return FALSE;
 519
 520 if (!break_link(US"input",  subdir, id, US"-H", from, FALSE) ||
 521     !break_link(US"input",  subdir, id, US"-D", from, FALSE) ||
 522     !break_link(US"msglog", subdir, id, US"", from, TRUE))
 523   return FALSE;
 524
 525 log_write(0, LOG_MAIN, "moved from %sinput, %smsglog to %sinput, %smsglog",
 526    from, from, to, to);
 527
 528 return TRUE;
 529 }
 530
 531 #endif
 532
 533 /* End of spool_out.c */
 534 /* vi: aw ai sw=2
 535 */