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 i;
 132 int size_correction;
 133 FILE * fp;
 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 fp = 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(fp, "%s-H\n", message_id);
 154 fprintf(fp, "%.63s %ld %ld\n", originator_login, (long int)originator_uid,
 155   (long int)originator_gid);
 156 fprintf(fp, "<%s>\n", sender_address);
 157 fprintf(fp, "%d %d\n", (int)received_time.tv_sec, warning_count);
 158
 159 fprintf(fp, "-received_time_usec .%06d\n", (int)received_time.tv_usec);
 160
 161 /* If there is information about a sending host, remember it. The HELO
 162 data can be set for local SMTP as well as remote. */
 163
 164 if (sender_helo_name)
 165   fprintf(fp, "-helo_name %s\n", sender_helo_name);
 166
 167 if (sender_host_address)
 168   {
 169   fprintf(fp, "-host_address %s.%d\n", sender_host_address, sender_host_port);
 170   if (sender_host_name)
 171     fprintf(fp, "-host_name %s\n", sender_host_name);
 172   if (sender_host_authenticated)
 173     fprintf(fp, "-host_auth %s\n", sender_host_authenticated);
 174   }
 175
 176 /* Also about the interface a message came in on */
 177
 178 if (interface_address)
 179   fprintf(fp, "-interface_address %s.%d\n", interface_address, interface_port);
 180
 181 if (smtp_active_hostname != primary_hostname)
 182   fprintf(fp, "-active_hostname %s\n", smtp_active_hostname);
 183
 184 /* Likewise for any ident information; for local messages this is
 185 likely to be the same as originator_login, but will be different if
 186 the originator was root, forcing a different ident. */
 187
 188 if (sender_ident) fprintf(fp, "-ident %s\n", sender_ident);
 189
 190 /* Ditto for the received protocol */
 191
 192 if (received_protocol)
 193   fprintf(fp, "-received_protocol %s\n", received_protocol);
 194
 195 /* Preserve any ACL variables that are set. */
 196
 197 tree_walk(acl_var_c, &acl_var_write, fp);
 198 tree_walk(acl_var_m, &acl_var_write, fp);
 199
 200 /* Now any other data that needs to be remembered. */
 201
 202 if (f.spool_file_wireformat)
 203   fprintf(fp, "-spool_file_wireformat\n");
 204 else
 205   fprintf(fp, "-body_linecount %d\n", body_linecount);
 206 fprintf(fp, "-max_received_linelength %d\n", max_received_linelength);
 207
 208 if (body_zerocount > 0) fprintf(fp, "-body_zerocount %d\n", body_zerocount);
 209
 210 if (authenticated_id)
 211   fprintf(fp, "-auth_id %s\n", authenticated_id);
 212 if (authenticated_sender)
 213   fprintf(fp, "-auth_sender %s\n", authenticated_sender);
 214
 215 if (f.allow_unqualified_recipient) fprintf(fp, "-allow_unqualified_recipient\n");
 216 if (f.allow_unqualified_sender) fprintf(fp, "-allow_unqualified_sender\n");
 217 if (f.deliver_firsttime) fprintf(fp, "-deliver_firsttime\n");
 218 if (f.deliver_freeze) fprintf(fp, "-frozen " TIME_T_FMT "\n", deliver_frozen_at);
 219 if (f.dont_deliver) fprintf(fp, "-N\n");
 220 if (host_lookup_deferred) fprintf(fp, "-host_lookup_deferred\n");
 221 if (host_lookup_failed) fprintf(fp, "-host_lookup_failed\n");
 222 if (f.sender_local) fprintf(fp, "-local\n");
 223 if (f.local_error_message) fprintf(fp, "-localerror\n");
 224 #ifdef HAVE_LOCAL_SCAN
 225 if (local_scan_data) fprintf(fp, "-local_scan %s\n", local_scan_data);
 226 #endif
 227 #ifdef WITH_CONTENT_SCAN
 228 if (spam_bar)       fprintf(fp,"-spam_bar %s\n",       spam_bar);
 229 if (spam_score)     fprintf(fp,"-spam_score %s\n",     spam_score);
 230 if (spam_score_int) fprintf(fp,"-spam_score_int %s\n", spam_score_int);
 231 #endif
 232 if (f.deliver_manual_thaw) fprintf(fp, "-manual_thaw\n");
 233 if (f.sender_set_untrusted) fprintf(fp, "-sender_set_untrusted\n");
 234
 235 #ifdef EXPERIMENTAL_BRIGHTMAIL
 236 if (bmi_verdicts) fprintf(fp, "-bmi_verdicts %s\n", bmi_verdicts);
 237 #endif
 238
 239 #ifdef SUPPORT_TLS
 240 if (tls_in.certificate_verified) fprintf(fp, "-tls_certificate_verified\n");
 241 if (tls_in.cipher)       fprintf(fp, "-tls_cipher %s\n", tls_in.cipher);
 242 if (tls_in.peercert)
 243   {
 244   (void) tls_export_cert(big_buffer, big_buffer_size, tls_in.peercert);
 245   fprintf(fp, "-tls_peercert %s\n", CS big_buffer);
 246   }
 247 if (tls_in.peerdn)       fprintf(fp, "-tls_peerdn %s\n", string_printing(tls_in.peerdn));
 248 if (tls_in.sni)          fprintf(fp, "-tls_sni %s\n",    string_printing(tls_in.sni));
 249 if (tls_in.ourcert)
 250   {
 251   (void) tls_export_cert(big_buffer, big_buffer_size, tls_in.ourcert);
 252   fprintf(fp, "-tls_ourcert %s\n", CS big_buffer);
 253   }
 254 if (tls_in.ocsp)         fprintf(fp, "-tls_ocsp %d\n",   tls_in.ocsp);
 255
 256 # ifdef EXPERIMENTAL_REQUIRETLS
 257 if (tls_requiretls)      fprintf(fp, "-tls_requiretls 0x%x\n", tls_requiretls);
 258 # endif
 259 #endif
 260
 261 #ifdef SUPPORT_I18N
 262 if (message_smtputf8)
 263   {
 264   fprintf(fp, "-smtputf8\n");
 265   if (message_utf8_downconvert)
 266     fprintf(fp, "-utf8_%sdowncvt\n", message_utf8_downconvert < 0 ? "opt" : "");
 267   }
 268 #endif
 269
 270 /* Write the dsn flags to the spool header file */
 271 DEBUG(D_deliver) debug_printf("DSN: Write SPOOL :-dsn_envid %s\n", dsn_envid);
 272 if (dsn_envid) fprintf(fp, "-dsn_envid %s\n", dsn_envid);
 273 DEBUG(D_deliver) debug_printf("DSN: Write SPOOL :-dsn_ret %d\n", dsn_ret);
 274 if (dsn_ret) fprintf(fp, "-dsn_ret %d\n", dsn_ret);
 275
 276 /* To complete the envelope, write out the tree of non-recipients, followed by
 277 the list of recipients. These won't be disjoint the first time, when no
 278 checking has been done. If a recipient is a "one-time" alias, it is followed by
 279 a space and its parent address number (pno). */
 280
 281 tree_write(tree_nonrecipients, fp);
 282 fprintf(fp, "%d\n", recipients_count);
 283 for (i = 0; i < recipients_count; i++)
 284   {
 285   recipient_item *r = recipients_list + i;
 286
 287   DEBUG(D_deliver) debug_printf("DSN: Flags :%d\n", r->dsn_flags);
 288
 289   if (r->pno < 0 && r->errors_to == NULL && r->dsn_flags == 0)
 290     fprintf(fp, "%s\n", r->address);
 291   else
 292     {
 293     uschar * errors_to = r->errors_to ? r->errors_to : US"";
 294     /* for DSN SUPPORT extend exim 4 spool in a compatible way by
 295     adding new values upfront and add flag 0x02 */
 296     uschar * orcpt = r->orcpt ? r->orcpt : US"";
 297
 298     fprintf(fp, "%s %s %d,%d %s %d,%d#3\n", r->address, orcpt, Ustrlen(orcpt),
 299       r->dsn_flags, errors_to, Ustrlen(errors_to), r->pno);
 300     }
 301
 302     DEBUG(D_deliver) debug_printf("DSN: **** SPOOL_OUT - "
 303       "address: |%s| errorsto: |%s| orcpt: |%s| dsn_flags: %d\n",
 304       r->address, r->errors_to, r->orcpt, r->dsn_flags);
 305   }
 306
 307 /* Put a blank line before the headers */
 308
 309 fprintf(fp, "\n");
 310
 311 /* Save the size of the file so far so we can subtract it from the final length
 312 to get the actual size of the headers. */
 313
 314 fflush(fp);
 315 if (fstat(fd, &statbuf))
 316   return spool_write_error(where, errmsg, US"fstat", tname, fp);
 317 size_correction = statbuf.st_size;
 318
 319 /* Finally, write out the message's headers. To make it easier to read them
 320 in again, precede each one with the count of its length. Make the count fixed
 321 length to aid human eyes when debugging and arrange for it not be included in
 322 the size. It is followed by a space for normal headers, a flagging letter for
 323 various other headers, or an asterisk for old headers that have been rewritten.
 324 These are saved as a record for debugging. Don't included them in the message's
 325 size. */
 326
 327 for (h = header_list; h; h = h->next)
 328   {
 329   fprintf(fp, "%03d%c %s", h->slen, h->type, h->text);
 330   size_correction += 5;
 331   if (h->type == '*') size_correction += h->slen;
 332   }
 333
 334 /* Flush and check for any errors while writing */
 335
 336 if (fflush(fp) != 0 || ferror(fp))
 337   return spool_write_error(where, errmsg, US"write", tname, fp);
 338
 339 /* Force the file's contents to be written to disk. Note that fflush()
 340 just pushes it out of C, and fclose() doesn't guarantee to do the write
 341 either. That's just the way Unix works... */
 342
 343 if (EXIMfsync(fileno(fp)) < 0)
 344   return spool_write_error(where, errmsg, US"sync", tname, fp);
 345
 346 /* Get the size of the file, and close it. */
 347
 348 if (fstat(fd, &statbuf) != 0)
 349   return spool_write_error(where, errmsg, US"fstat", tname, NULL);
 350 if (fclose(fp) != 0)
 351   return spool_write_error(where, errmsg, US"close", tname, NULL);
 352
 353 /* Rename the file to its correct name, thereby replacing any previous
 354 incarnation. */
 355
 356 fname = spool_fname(US"input", message_subdir, id, US"-H");
 357 DEBUG(D_receive|D_deliver) debug_printf("Renaming spool header file: %s\n", fname);
 358
 359 if (Urename(tname, fname) < 0)
 360   return spool_write_error(where, errmsg, US"rename", tname, NULL);
 361
 362 /* Linux (and maybe other OS?) does not automatically sync a directory after
 363 an operation like rename. We therefore have to do it forcibly ourselves in
 364 these cases, to make sure the file is actually accessible on disk, as opposed
 365 to just the data being accessible from a file in lost+found. Linux also has
 366 O_DIRECTORY, for opening a directory.
 367
 368 However, it turns out that some file systems (some versions of NFS?) do not
 369 support directory syncing. It seems safe enough to ignore EINVAL to cope with
 370 these cases. One hack on top of another... but that's life. */
 371
 372 #ifdef NEED_SYNC_DIRECTORY
 373
 374 tname = spool_fname(US"input", message_subdir, US".", US"");
 375
 376 # ifndef O_DIRECTORY
 377 #  define O_DIRECTORY 0
 378 # endif
 379
 380 if ((fd = Uopen(tname, O_RDONLY|O_DIRECTORY, 0)) < 0)
 381   return spool_write_error(where, errmsg, US"directory open", fname, NULL);
 382
 383 if (EXIMfsync(fd) < 0 && errno != EINVAL)
 384   return spool_write_error(where, errmsg, US"directory sync", fname, NULL);
 385
 386 if (close(fd) < 0)
 387   return spool_write_error(where, errmsg, US"directory close", fname, NULL);
 388
 389 #endif  /* NEED_SYNC_DIRECTORY */
 390
 391 /* Return the number of characters in the headers, which is the file size, less
 392 the preliminary stuff, less the additional count fields on the headers. */
 393
 394 DEBUG(D_receive) debug_printf("Size of headers = %d\n",
 395   (int)(statbuf.st_size - size_correction));
 396
 397 return statbuf.st_size - size_correction;
 398 }
 399
 400
 401 #ifdef SUPPORT_MOVE_FROZEN_MESSAGES
 402
 403 /************************************************
 404 *              Make a hard link                 *
 405 ************************************************/
 406
 407 /* Used by spool_move_message() below. Note re the use of sprintf(): the value
 408 of spool_directory is checked to ensure that it is less than 200 characters at
 409 start-up time.
 410
 411 Arguments:
 412   dir        base directory name
 413   subdir     subdirectory name
 414   id         message id
 415   suffix     suffix to add to id
 416   from       source directory prefix
 417   to         destination directory prefix
 418   noentok    if TRUE, absence of file is not an error
 419
 420 Returns:     TRUE if all went well
 421              FALSE, having panic logged if not
 422 */
 423
 424 static BOOL
 425 make_link(uschar *dir, uschar *subdir, uschar *id, uschar *suffix, uschar *from,
 426   uschar *to, BOOL noentok)
 427 {
 428 uschar * fname = spool_fname(string_sprintf("%s%s", from, dir), subdir, id, suffix);
 429 uschar * tname = spool_fname(string_sprintf("%s%s", to,   dir), subdir, id, suffix);
 430 if (Ulink(fname, tname) < 0 && (!noentok || errno != ENOENT))
 431   {
 432   log_write(0, LOG_MAIN|LOG_PANIC, "link(\"%s\", \"%s\") failed while moving "
 433     "message: %s", fname, tname, strerror(errno));
 434   return FALSE;
 435   }
 436 return TRUE;
 437 }
 438
 439
 440
 441 /************************************************
 442 *                Break a link                   *
 443 ************************************************/
 444
 445 /* Used by spool_move_message() below. Note re the use of sprintf(): the value
 446 of spool_directory is checked to ensure that it is less than 200 characters at
 447 start-up time.
 448
 449 Arguments:
 450   dir        base directory name
 451   subdir     subdirectory name
 452   id         message id
 453   suffix     suffix to add to id
 454   from       source directory prefix
 455   noentok    if TRUE, absence of file is not an error
 456
 457 Returns:     TRUE if all went well
 458              FALSE, having panic logged if not
 459 */
 460
 461 static BOOL
 462 break_link(uschar *dir, uschar *subdir, uschar *id, uschar *suffix, uschar *from,
 463   BOOL noentok)
 464 {
 465 uschar * fname = spool_fname(string_sprintf("%s%s", from, dir), subdir, id, suffix);
 466 if (Uunlink(fname) < 0 && (!noentok || errno != ENOENT))
 467   {
 468   log_write(0, LOG_MAIN|LOG_PANIC, "unlink(\"%s\") failed while moving "
 469     "message: %s", fname, strerror(errno));
 470   return FALSE;
 471   }
 472 return TRUE;
 473 }
 474
 475
 476
 477 /************************************************
 478 *            Move message files                 *
 479 ************************************************/
 480
 481 /* Move the files for a message (-H, -D, and msglog) from one directory (or
 482 hierarchy) to another. It is assume that there is no -J file in existence when
 483 this is done. At present, this is used only when move_frozen_messages is set,
 484 so compile it only when that support is configured.
 485
 486 Arguments:
 487   id          the id of the message to be delivered
 488   subdir      the subdirectory name, or an empty string
 489   from        a prefix for "input" or "msglog" for where the message is now
 490   to          a prefix for "input" or "msglog" for where the message is to go
 491
 492 Returns:      TRUE if all is well
 493               FALSE if not, with error logged in panic and main logs
 494 */
 495
 496 BOOL
 497 spool_move_message(uschar *id, uschar *subdir, uschar *from, uschar *to)
 498 {
 499 /* Create any output directories that do not exist. */
 500
 501 (void) directory_make(spool_directory,
 502   spool_sname(string_sprintf("%sinput", to), subdir),
 503   INPUT_DIRECTORY_MODE, TRUE);
 504 (void) directory_make(spool_directory,
 505   spool_sname(string_sprintf("%smsglog", to), subdir),
 506   INPUT_DIRECTORY_MODE, TRUE);
 507
 508 /* Move the message by first creating new hard links for all the files, and
 509 then removing the old links. When moving messages onto the main spool, the -H
 510 file should be set up last, because that's the one that tells Exim there is a
 511 message to be delivered, so we create its new link last and remove its old link
 512 first. Programs that look at the alternate directories should follow the same
 513 rule of waiting for a -H file before doing anything. When moving messages off
 514 the mail spool, the -D file should be open and locked at the time, thus keeping
 515 Exim's hands off. */
 516
 517 if (!make_link(US"msglog", subdir, id, US"", from, to, TRUE) ||
 518     !make_link(US"input",  subdir, id, US"-D", from, to, FALSE) ||
 519     !make_link(US"input",  subdir, id, US"-H", from, to, FALSE))
 520   return FALSE;
 521
 522 if (!break_link(US"input",  subdir, id, US"-H", from, FALSE) ||
 523     !break_link(US"input",  subdir, id, US"-D", from, FALSE) ||
 524     !break_link(US"msglog", subdir, id, US"", from, TRUE))
 525   return FALSE;
 526
 527 log_write(0, LOG_MAIN, "moved from %sinput, %smsglog to %sinput, %smsglog",
 528    from, from, to, to);
 529
 530 return TRUE;
 531 }
 532
 533 #endif
 534
 535 /* End of spool_out.c */
 536 /* vi: aw ai sw=2
 537 */