src/src/spool_out.c

   1 /* $Cambridge: exim/src/src/spool_out.c,v 1.6 2005/02/17 11:58:26 ph10 Exp $ */
   2
   3 /*************************************************
   4 *     Exim - an Internet mail transport agent    *
   5 *************************************************/
   6
   7 /* Copyright (c) University of Cambridge 1995 - 2005 */
   8 /* See the file NOTICE for conditions of use and distribution. */
   9
  10 /* Functions for writing spool files, and moving them about. */
  11
  12
  13 #include "exim.h"
  14
  15
  16
  17 /*************************************************
  18 *       Deal with header writing errors          *
  19 *************************************************/
  20
  21 /* This function is called immediately after errors in writing the spool, with
  22 errno still set. It creates and error message, depending on the circumstances.
  23 If errmsg is NULL, it logs the message and panic-dies. Otherwise errmsg is set
  24 to point to the message, and -1 is returned. This function makes the code of
  25 spool_write_header() a bit neater.
  26
  27 Arguments:
  28    where      SW_RECEIVING, SW_DELIVERING, or SW_MODIFYING
  29    errmsg     where to put the message; NULL => panic-die
  30    s          text to add to log string
  31    temp_name  name of temp file to unlink
  32    f          FILE to close, if not NULL
  33
  34 Returns:      -1 if errmsg is not NULL; otherwise doesn't return
  35 */
  36
  37 static int
  38 spool_write_error(int where, uschar **errmsg, uschar *s, uschar *temp_name,
  39   FILE *f)
  40 {
  41 uschar *msg = (where == SW_RECEIVING)?
  42   string_sprintf("spool file %s error while receiving from %s: %s", s,
  43     (sender_fullhost != NULL)? sender_fullhost : sender_ident,
  44     strerror(errno))
  45   :
  46   string_sprintf("spool file %s error while %s: %s", s,
  47     (where == SW_DELIVERING)? "delivering" : "modifying",
  48     strerror(errno));
  49
  50 if (temp_name != NULL) Uunlink(temp_name);
  51 if (f != NULL) fclose(f);
  52
  53 if (errmsg == NULL)
  54   log_write(0, LOG_MAIN|LOG_PANIC_DIE, "%s", msg);
  55 else
  56   *errmsg = msg;
  57
  58 return -1;
  59 }
  60
  61
  62
  63 /*************************************************
  64 *            Open file under temporary name      *
  65 *************************************************/
  66
  67 /* This is used for opening spool files under a temporary name,
  68 with a single attempt at deleting if they already exist.
  69
  70 Argument: temporary name for spool header file
  71 Returns:  file descriptor of open file, or < 0 on failure, with errno unchanged
  72 */
  73
  74 int
  75 spool_open_temp(uschar *temp_name)
  76 {
  77 int fd = Uopen(temp_name, O_RDWR|O_CREAT|O_EXCL, SPOOL_MODE);
  78
  79 /* If the file already exists, something has gone wrong. This process may well
  80 have previously created the file if it is delivering more than one address, but
  81 it should have renamed it almost immediately. A file could, however, be left
  82 around as a result of a system crash, and by coincidence this process might
  83 have the same pid. We therefore have one go at unlinking it before giving up.
  84 */
  85
  86 if (fd < 0 && errno == EEXIST)
  87   {
  88   DEBUG(D_any) debug_printf("%s exists: unlinking\n", temp_name);
  89   Uunlink(temp_name);
  90   fd = Uopen(temp_name, O_RDWR|O_CREAT|O_EXCL, SPOOL_MODE);
  91   }
  92
  93 /* If the file has been opened, make sure the file's group is the Exim gid, and
  94 double-check the mode because the group setting doesn't always get set
  95 automatically. */
  96
  97 if (fd >= 0)
  98   {
  99   fchown(fd, exim_uid, exim_gid);
 100   fchmod(fd, SPOOL_MODE);
 101   }
 102
 103 return fd;
 104 }
 105
 106
 107
 108 /*************************************************
 109 *          Write the header spool file           *
 110 *************************************************/
 111
 112 /* Returns the size of the file for success; zero for failure. The file is
 113 written under a temporary name, and then renamed. It's done this way so that it
 114 works with re-writing the file on message deferral as well as for the initial
 115 write. Whenever this function is called, the data file for the message should
 116 be open and locked, thus preventing any other exim process from working on this
 117 message.
 118
 119 Argument:
 120   id      the message id
 121   where   SW_RECEIVING, SW_DELIVERING, or SW_MODIFYING
 122   errmsg  where to put an error message; if NULL, panic-die on error
 123
 124 Returns:  the size of the header texts on success;
 125           negative on writing failure, unless errmsg == NULL
 126 */
 127
 128 int
 129 spool_write_header(uschar *id, int where, uschar **errmsg)
 130 {
 131 int fd;
 132 int i;
 133 int size_correction;
 134 FILE *f;
 135 header_line *h;
 136 struct stat statbuf;
 137 uschar name[256];
 138 uschar temp_name[256];
 139
 140 sprintf(CS temp_name, "%s/input/%s/hdr.%d", spool_directory, message_subdir,
 141   (int)getpid());
 142 fd = spool_open_temp(temp_name);
 143 if (fd < 0) 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\n");
 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. Because the values may contain
 194 newlines, we use an explicit length. */
 195
 196 for (i = 0; i < ACL_C_MAX + ACL_M_MAX; i++)
 197   {
 198   if (acl_var[i] != NULL)
 199     fprintf(f, "-acl %d %d\n%s\n", i, Ustrlen(acl_var[i]), acl_var[i]);
 200   }
 201
 202 /* Now any other data that needs to be remembered. */
 203
 204 fprintf(f, "-body_linecount %d\n", body_linecount);
 205
 206 if (body_zerocount > 0) fprintf(f, "-body_zerocount %d\n", body_zerocount);
 207
 208 if (authenticated_id != NULL)
 209   fprintf(f, "-auth_id %s\n", authenticated_id);
 210 if (authenticated_sender != NULL)
 211   fprintf(f, "-auth_sender %s\n", authenticated_sender);
 212
 213 if (allow_unqualified_recipient) fprintf(f, "-allow_unqualified_recipient\n");
 214 if (allow_unqualified_sender) fprintf(f, "-allow_unqualified_sender\n");
 215 if (deliver_firsttime) fprintf(f, "-deliver_firsttime\n");
 216 if (deliver_freeze) fprintf(f, "-frozen %d\n", deliver_frozen_at);
 217 if (dont_deliver) fprintf(f, "-N\n");
 218 if (host_lookup_deferred) fprintf(f, "-host_lookup_deferred\n");
 219 if (host_lookup_failed) fprintf(f, "-host_lookup_failed\n");
 220 if (sender_local) fprintf(f, "-local\n");
 221 if (local_error_message) fprintf(f, "-localerror\n");
 222 if (local_scan_data != NULL) fprintf(f, "-local_scan %s\n", local_scan_data);
 223 #ifdef WITH_CONTENT_SCAN
 224 if (spam_score_int != NULL) fprintf(f,"-spam_score_int %s\n", spam_score_int);
 225 #endif
 226 if (deliver_manual_thaw) fprintf(f, "-manual_thaw\n");
 227 if (sender_set_untrusted) fprintf(f, "-sender_set_untrusted\n");
 228
 229 #ifdef EXPERIMENTAL_BRIGHTMAIL
 230 if (bmi_verdicts != NULL) fprintf(f, "-bmi_verdicts %s\n", bmi_verdicts);
 231 #endif
 232
 233 #ifdef SUPPORT_TLS
 234 if (tls_certificate_verified) fprintf(f, "-tls_certificate_verified\n");
 235 if (tls_cipher != NULL) fprintf(f, "-tls_cipher %s\n", tls_cipher);
 236 if (tls_peerdn != NULL) fprintf(f, "-tls_peerdn %s\n", tls_peerdn);
 237 #endif
 238
 239 /* To complete the envelope, write out the tree of non-recipients, followed by
 240 the list of recipients. These won't be disjoint the first time, when no
 241 checking has been done. If a recipient is a "one-time" alias, it is followed by
 242 a space and its parent address number (pno). */
 243
 244 tree_write(tree_nonrecipients, f);
 245 fprintf(f, "%d\n", recipients_count);
 246 for (i = 0; i < recipients_count; i++)
 247   {
 248   recipient_item *r = recipients_list + i;
 249   if (r->pno < 0 && r->errors_to == NULL)
 250     fprintf(f, "%s\n", r->address);
 251   else
 252     {
 253     uschar *errors_to = (r->errors_to == NULL)? US"" : r->errors_to;
 254     fprintf(f, "%s %s %d,%d#1\n", r->address, errors_to,
 255       Ustrlen(errors_to), r->pno);
 256     }
 257   }
 258
 259 /* Put a blank line before the headers */
 260
 261 fprintf(f, "\n");
 262
 263 /* Save the size of the file so far so we can subtract it from the final length
 264 to get the actual size of the headers. */
 265
 266 fflush(f);
 267 fstat(fd, &statbuf);
 268 size_correction = statbuf.st_size;
 269
 270 /* Finally, write out the message's headers. To make it easier to read them
 271 in again, precede each one with the count of its length. Make the count fixed
 272 length to aid human eyes when debugging and arrange for it not be included in
 273 the size. It is followed by a space for normal headers, a flagging letter for
 274 various other headers, or an asterisk for old headers that have been rewritten.
 275 These are saved as a record for debugging. Don't included them in the message's
 276 size. */
 277
 278 for (h = header_list; h != NULL; h = h->next)
 279   {
 280   fprintf(f, "%03d%c %s", h->slen, h->type, h->text);
 281   size_correction += 5;
 282   if (h->type == '*') size_correction += h->slen;
 283   }
 284
 285 /* Flush and check for any errors while writing */
 286
 287 if (fflush(f) != 0 || ferror(f))
 288   return spool_write_error(where, errmsg, US"write", temp_name, f);
 289
 290 /* Force the file's contents to be written to disk. Note that fflush()
 291 just pushes it out of C, and fclose() doesn't guarantee to do the write
 292 either. That's just the way Unix works... */
 293
 294 if (fsync(fileno(f)) < 0)
 295   return spool_write_error(where, errmsg, US"sync", temp_name, f);
 296
 297 /* Get the size of the file, and close it. */
 298
 299 fstat(fd, &statbuf);
 300 if (fclose(f) != 0)
 301   return spool_write_error(where, errmsg, US"close", temp_name, NULL);
 302
 303 /* Rename the file to its correct name, thereby replacing any previous
 304 incarnation. */
 305
 306 sprintf(CS name, "%s/input/%s/%s-H", spool_directory, message_subdir, id);
 307
 308 if (Urename(temp_name, name) < 0)
 309   return spool_write_error(where, errmsg, US"rename", temp_name, NULL);
 310
 311 /* Linux (and maybe other OS?) does not automatically sync a directory after
 312 an operation like rename. We therefore have to do it forcibly ourselves in
 313 these cases, to make sure the file is actually accessible on disk, as opposed
 314 to just the data being accessible from a file in lost+found. Linux also has
 315 O_DIRECTORY, for opening a directory.
 316
 317 However, it turns out that some file systems (some versions of NFS?) do not
 318 support directory syncing. It seems safe enough to ignore EINVAL to cope with
 319 these cases. One hack on top of another... but that's life. */
 320
 321 #ifdef NEED_SYNC_DIRECTORY
 322
 323 sprintf(CS temp_name, "%s/input/%s/.", spool_directory, message_subdir);
 324
 325 #ifndef O_DIRECTORY
 326 #define O_DIRECTORY 0
 327 #endif
 328
 329 if ((fd = Uopen(temp_name, O_RDONLY|O_DIRECTORY, 0)) < 0)
 330   return spool_write_error(where, errmsg, US"directory open", name, NULL);
 331
 332 if (fsync(fd) < 0 && errno != EINVAL)
 333   return spool_write_error(where, errmsg, US"directory sync", name, NULL);
 334
 335 if (close(fd) < 0)
 336   return spool_write_error(where, errmsg, US"directory close", name, NULL);
 337
 338 #endif  /* NEED_SYNC_DIRECTORY */
 339
 340 /* Return the number of characters in the headers, which is the file size, less
 341 the prelimary stuff, less the additional count fields on the headers. */
 342
 343 DEBUG(D_receive) debug_printf("Size of headers = %d\n",
 344   (int)(statbuf.st_size - size_correction));
 345
 346 return statbuf.st_size - size_correction;
 347 }
 348
 349
 350 #ifdef SUPPORT_MOVE_FROZEN_MESSAGES
 351
 352 /************************************************
 353 *              Make a hard link                 *
 354 ************************************************/
 355
 356 /* Used by spool_move_message() below. Note re the use of sprintf(): the value
 357 of spool_directory is checked to ensure that it is less than 200 characters at
 358 start-up time.
 359
 360 Arguments:
 361   dir        base directory name
 362   subdir     subdirectory name
 363   id         message id
 364   suffix     suffix to add to id
 365   from       source directory prefix
 366   to         destination directory prefix
 367   noentok    if TRUE, absence of file is not an error
 368
 369 Returns:     TRUE if all went well
 370              FALSE, having panic logged if not
 371 */
 372
 373 static BOOL
 374 make_link(uschar *dir, uschar *subdir, uschar *id, uschar *suffix, uschar *from,
 375   uschar *to, BOOL noentok)
 376 {
 377 uschar f[256], t[256];
 378 sprintf(CS f, "%s/%s%s/%s/%s%s", spool_directory, from, dir, subdir, id, suffix);
 379 sprintf(CS t, "%s/%s%s/%s/%s%s", spool_directory, to, dir, subdir, id, suffix);
 380 if (Ulink(f, t) < 0 && (!noentok || errno != ENOENT))
 381   {
 382   log_write(0, LOG_MAIN|LOG_PANIC, "link(\"%s\", \"%s\") failed while moving "
 383     "message: %s", f, t, strerror(errno));
 384   return FALSE;
 385   }
 386 return TRUE;
 387 }
 388
 389
 390
 391 /************************************************
 392 *                Break a link                   *
 393 ************************************************/
 394
 395 /* Used by spool_move_message() below. Note re the use of sprintf(): the value
 396 of spool_directory is checked to ensure that it is less than 200 characters at
 397 start-up time.
 398
 399 Arguments:
 400   dir        base directory name
 401   subdir     subdirectory name
 402   id         message id
 403   suffix     suffix to add to id
 404   from       source directory prefix
 405   noentok    if TRUE, absence of file is not an error
 406
 407 Returns:     TRUE if all went well
 408              FALSE, having panic logged if not
 409 */
 410
 411 static BOOL
 412 break_link(uschar *dir, uschar *subdir, uschar *id, uschar *suffix, uschar *from,
 413   BOOL noentok)
 414 {
 415 uschar f[256];
 416 sprintf(CS f, "%s/%s%s/%s/%s%s", spool_directory, from, dir, subdir, id, suffix);
 417 if (Uunlink(f) < 0 && (!noentok || errno != ENOENT))
 418   {
 419   log_write(0, LOG_MAIN|LOG_PANIC, "unlink(\"%s\") failed while moving "
 420     "message: %s", f, strerror(errno));
 421   return FALSE;
 422   }
 423 return TRUE;
 424 }
 425
 426
 427
 428 /************************************************
 429 *            Move message files                 *
 430 ************************************************/
 431
 432 /* Move the files for a message (-H, -D, and msglog) from one directory (or
 433 hierarchy) to another. It is assume that there is no -J file in existence when
 434 this is done. At present, this is used only when move_frozen_messages is set,
 435 so compile it only when that support is configured.
 436
 437 Arguments:
 438   id          the id of the message to be delivered
 439   subdir      the subdirectory name, or an empty string
 440   from        a prefix for "input" or "msglog" for where the message is now
 441   to          a prefix for "input" or "msglog" for where the message is to go
 442
 443 Returns:      TRUE if all is well
 444               FALSE if not, with error logged in panic and main logs
 445 */
 446
 447 BOOL
 448 spool_move_message(uschar *id, uschar *subdir, uschar *from, uschar *to)
 449 {
 450 /* Create any output directories that do not exist. */
 451
 452 sprintf(CS big_buffer, "%sinput/%s", to, subdir);
 453 (void)directory_make(spool_directory, big_buffer, INPUT_DIRECTORY_MODE, TRUE);
 454 sprintf(CS big_buffer, "%smsglog/%s", to, subdir);
 455 (void)directory_make(spool_directory, big_buffer, INPUT_DIRECTORY_MODE, TRUE);
 456
 457 /* Move the message by first creating new hard links for all the files, and
 458 then removing the old links. When moving messages onto the main spool, the -H
 459 file should be set up last, because that's the one that tells Exim there is a
 460 message to be delivered, so we create its new link last and remove its old link
 461 first. Programs that look at the alternate directories should follow the same
 462 rule of waiting for a -H file before doing anything. When moving messsages off
 463 the mail spool, the -D file should be open and locked at the time, thus keeping
 464 Exim's hands off. */
 465
 466 if (!make_link(US"msglog", subdir, id, US"", from, to, TRUE) ||
 467     !make_link(US"input",  subdir, id, US"-D", from, to, FALSE) ||
 468     !make_link(US"input",  subdir, id, US"-H", from, to, FALSE))
 469   return FALSE;
 470
 471 if (!break_link(US"input",  subdir, id, US"-H", from, FALSE) ||
 472     !break_link(US"input",  subdir, id, US"-D", from, FALSE) ||
 473     !break_link(US"msglog", subdir, id, US"", from, TRUE))
 474   return FALSE;
 475
 476 log_write(0, LOG_MAIN, "moved from %sinput, %smsglog to %sinput, %smsglog",
 477    from, from, to, to);
 478
 479 return TRUE;
 480 }
 481
 482 #endif
 483
 484 /* End of spool_out.c */