1 /* $NetBSD: flush.c,v 1.1.1.1 2009/06/23 10:08:44 tron Exp $ */ 2 3 /*++ 4 /* NAME 5 /* flush 8 6 /* SUMMARY 7 /* Postfix fast flush server 8 /* SYNOPSIS 9 /* \fBflush\fR [generic Postfix daemon options] 10 /* DESCRIPTION 11 /* The \fBflush\fR(8) server maintains a record of deferred 12 /* mail by destination. 13 /* This information is used to improve the performance of the SMTP 14 /* \fBETRN\fR request, and of its command-line equivalent, 15 /* "\fBsendmail -qR\fR" or "\fBpostqueue -f\fR". 16 /* This program expects to be run from the \fBmaster\fR(8) process 17 /* manager. 18 /* 19 /* The record is implemented as a per-destination logfile with 20 /* as contents the queue IDs of deferred mail. A logfile is 21 /* append-only, and is truncated when delivery is requested 22 /* for the corresponding destination. A destination is the 23 /* part on the right-hand side of the right-most \fB@\fR in 24 /* an email address. 25 /* 26 /* Per-destination logfiles of deferred mail are maintained only for 27 /* eligible destinations. The list of eligible destinations is 28 /* specified with the \fBfast_flush_domains\fR configuration parameter, 29 /* which defaults to \fB$relay_domains\fR. 30 /* 31 /* This server implements the following requests: 32 /* .IP "\fBadd\fI sitename queueid\fR" 33 /* Inform the \fBflush\fR(8) server that the message with the specified 34 /* queue ID is queued for the specified destination. 35 /* .IP "\fBsend_site\fI sitename\fR" 36 /* Request delivery of mail that is queued for the specified 37 /* destination. 38 /* .IP "\fBsend_file\fI queueid\fR" 39 /* Request delivery of the specified deferred message. 40 /* .IP \fBrefresh\fR 41 /* Refresh non-empty per-destination logfiles that were not read in 42 /* \fB$fast_flush_refresh_time\fR hours, by simulating 43 /* send requests (see above) for the corresponding destinations. 44 /* .sp 45 /* Delete empty per-destination logfiles that were not updated in 46 /* \fB$fast_flush_purge_time\fR days. 47 /* .sp 48 /* This request completes in the background. 49 /* .IP \fBpurge\fR 50 /* Do a \fBrefresh\fR for all per-destination logfiles. 51 /* SECURITY 52 /* .ad 53 /* .fi 54 /* The \fBflush\fR(8) server is not security-sensitive. It does not 55 /* talk to the network, and it does not talk to local users. 56 /* The fast flush server can run chrooted at fixed low privilege. 57 /* DIAGNOSTICS 58 /* Problems and transactions are logged to \fBsyslogd\fR(8). 59 /* BUGS 60 /* Fast flush logfiles are truncated only after a "send" 61 /* request, not when mail is actually delivered, and therefore can 62 /* accumulate outdated or redundant data. In order to maintain sanity, 63 /* "refresh" must be executed periodically. This can 64 /* be automated with a suitable wakeup timer setting in the 65 /* \fBmaster.cf\fR configuration file. 66 /* 67 /* Upon receipt of a request to deliver mail for an eligible 68 /* destination, the \fBflush\fR(8) server requests delivery of all messages 69 /* that are listed in that destination's logfile, regardless of the 70 /* recipients of those messages. This is not an issue for mail 71 /* that is sent to a \fBrelay_domains\fR destination because 72 /* such mail typically only has recipients in one domain. 73 /* CONFIGURATION PARAMETERS 74 /* .ad 75 /* .fi 76 /* Changes to \fBmain.cf\fR are picked up automatically as \fBflush\fR(8) 77 /* processes run for only a limited amount of time. Use the command 78 /* "\fBpostfix reload\fR" to speed up a change. 79 /* 80 /* The text below provides only a parameter summary. See 81 /* \fBpostconf\fR(5) for more details including examples. 82 /* .IP "\fBconfig_directory (see 'postconf -d' output)\fR" 83 /* The default location of the Postfix main.cf and master.cf 84 /* configuration files. 85 /* .IP "\fBdaemon_timeout (18000s)\fR" 86 /* How much time a Postfix daemon process may take to handle a 87 /* request before it is terminated by a built-in watchdog timer. 88 /* .IP "\fBfast_flush_domains ($relay_domains)\fR" 89 /* Optional list of destinations that are eligible for per-destination 90 /* logfiles with mail that is queued to those destinations. 91 /* .IP "\fBfast_flush_refresh_time (12h)\fR" 92 /* The time after which a non-empty but unread per-destination "fast 93 /* flush" logfile needs to be refreshed. 94 /* .IP "\fBfast_flush_purge_time (7d)\fR" 95 /* The time after which an empty per-destination "fast flush" logfile 96 /* is deleted. 97 /* .IP "\fBipc_timeout (3600s)\fR" 98 /* The time limit for sending or receiving information over an internal 99 /* communication channel. 100 /* .IP "\fBmax_idle (100s)\fR" 101 /* The maximum amount of time that an idle Postfix daemon process waits 102 /* for an incoming connection before terminating voluntarily. 103 /* .IP "\fBmax_use (100)\fR" 104 /* The maximal number of incoming connections that a Postfix daemon 105 /* process will service before terminating voluntarily. 106 /* .IP "\fBparent_domain_matches_subdomains (see 'postconf -d' output)\fR" 107 /* What Postfix features match subdomains of "domain.tld" automatically, 108 /* instead of requiring an explicit ".domain.tld" pattern. 109 /* .IP "\fBprocess_id (read-only)\fR" 110 /* The process ID of a Postfix command or daemon process. 111 /* .IP "\fBprocess_name (read-only)\fR" 112 /* The process name of a Postfix command or daemon process. 113 /* .IP "\fBqueue_directory (see 'postconf -d' output)\fR" 114 /* The location of the Postfix top-level queue directory. 115 /* .IP "\fBsyslog_facility (mail)\fR" 116 /* The syslog facility of Postfix logging. 117 /* .IP "\fBsyslog_name (see 'postconf -d' output)\fR" 118 /* The mail system name that is prepended to the process name in syslog 119 /* records, so that "smtpd" becomes, for example, "postfix/smtpd". 120 /* FILES 121 /* /var/spool/postfix/flush, "fast flush" logfiles. 122 /* SEE ALSO 123 /* smtpd(8), SMTP server 124 /* qmgr(8), queue manager 125 /* postconf(5), configuration parameters 126 /* master(5), generic daemon options 127 /* master(8), process manager 128 /* syslogd(8), system logging 129 /* README FILES 130 /* .ad 131 /* .fi 132 /* Use "\fBpostconf readme_directory\fR" or 133 /* "\fBpostconf html_directory\fR" to locate this information. 134 /* .na 135 /* .nf 136 /* ETRN_README, Postfix ETRN howto 137 /* LICENSE 138 /* .ad 139 /* .fi 140 /* The Secure Mailer license must be distributed with this software. 141 /* HISTORY 142 /* This service was introduced with Postfix version 1.0. 143 /* AUTHOR(S) 144 /* Wietse Venema 145 /* IBM T.J. Watson Research 146 /* P.O. Box 704 147 /* Yorktown Heights, NY 10598, USA 148 /*--*/ 149 150 /* System library. */ 151 152 #include <sys_defs.h> 153 #include <sys/stat.h> 154 #include <sys/time.h> 155 #include <unistd.h> 156 #include <stdlib.h> 157 #include <utime.h> 158 #include <errno.h> 159 #include <ctype.h> 160 #include <string.h> 161 162 /* Utility library. */ 163 164 #include <msg.h> 165 #include <events.h> 166 #include <vstream.h> 167 #include <vstring.h> 168 #include <vstring_vstream.h> 169 #include <myflock.h> 170 #include <htable.h> 171 #include <dict.h> 172 #include <scan_dir.h> 173 #include <stringops.h> 174 #include <safe_open.h> 175 176 /* Global library. */ 177 178 #include <mail_params.h> 179 #include <mail_version.h> 180 #include <mail_queue.h> 181 #include <mail_proto.h> 182 #include <mail_flush.h> 183 #include <flush_clnt.h> 184 #include <mail_conf.h> 185 #include <mail_scan_dir.h> 186 #include <maps.h> 187 #include <domain_list.h> 188 #include <match_parent_style.h> 189 190 /* Single server skeleton. */ 191 192 #include <mail_server.h> 193 194 /* Application-specific. */ 195 196 /* 197 * Tunable parameters. The fast_flush_domains parameter is not defined here, 198 * because it is also used by the global library, and therefore is owned by 199 * the library. 200 */ 201 int var_fflush_refresh; 202 int var_fflush_purge; 203 204 /* 205 * Flush policy stuff. 206 */ 207 static DOMAIN_LIST *flush_domains; 208 209 /* 210 * Some hard-wired policy: how many queue IDs we remember while we're 211 * flushing a logfile (duplicate elimination). Sites with 1000+ emails 212 * queued should arrange for permanent connectivity. 213 */ 214 #define FLUSH_DUP_FILTER_SIZE 10000 /* graceful degradation */ 215 216 /* 217 * Silly little macros. 218 */ 219 #define STR(x) vstring_str(x) 220 #define STREQ(x,y) ((x) == (y) || strcmp(x,y) == 0) 221 222 /* 223 * Forward declarations resulting from breaking up routines according to 224 * name space: domain names versus safe-to-use pathnames. 225 */ 226 static int flush_add_path(const char *, const char *); 227 static int flush_send_path(const char *, int); 228 229 /* 230 * Do we only refresh the per-destination logfile, or do we really request 231 * mail delivery as if someone sent ETRN? If the latter, we must override 232 * information about unavailable hosts or unavailable transports. 233 * 234 * When selectively flushing deferred mail, we need to override the queue 235 * manager's "dead destination" information and unthrottle transports and 236 * queues. There are two options: 237 * 238 * - Unthrottle all transports and queues before we move mail to the incoming 239 * queue. This is less accurate, but has the advantage when flushing lots of 240 * mail, because Postfix can skip delivery of flushed messages after it 241 * discovers that a destination is (still) unavailable. 242 * 243 * - Unthrottle some transports and queues after the queue manager moves mail 244 * to the active queue. This is more accurate, but has the disadvantage when 245 * flushing lots of mail, because Postfix cannot skip delivery of flushed 246 * messages after it discovers that a destination is (still) unavailable. 247 */ 248 #define REFRESH_ONLY 0 249 #define UNTHROTTLE_BEFORE (1<<0) 250 #define UNTHROTTLE_AFTER (1<<1) 251 252 /* flush_site_to_path - convert domain or [addr] to harmless string */ 253 254 static VSTRING *flush_site_to_path(VSTRING *path, const char *site) 255 { 256 const char *ptr; 257 int ch; 258 259 /* 260 * Allocate buffer on the fly; caller still needs to clean up. 261 */ 262 if (path == 0) 263 path = vstring_alloc(10); 264 265 /* 266 * Mask characters that could upset the name-to-queue-file mapping code. 267 */ 268 for (ptr = site; (ch = *(unsigned const char *) ptr) != 0; ptr++) 269 if (ISALNUM(ch)) 270 VSTRING_ADDCH(path, ch); 271 else 272 VSTRING_ADDCH(path, '_'); 273 VSTRING_TERMINATE(path); 274 275 if (msg_verbose) 276 msg_info("site %s to path %s", site, STR(path)); 277 278 return (path); 279 } 280 281 /* flush_policy_ok - check logging policy */ 282 283 static int flush_policy_ok(const char *site) 284 { 285 return (domain_list_match(flush_domains, site)); 286 } 287 288 /* flush_add_service - append queue ID to per-site fast flush logfile */ 289 290 static int flush_add_service(const char *site, const char *queue_id) 291 { 292 const char *myname = "flush_add_service"; 293 VSTRING *site_path; 294 int status; 295 296 if (msg_verbose) 297 msg_info("%s: site %s queue_id %s", myname, site, queue_id); 298 299 /* 300 * If this site is not eligible for logging, deny the request. 301 */ 302 if (flush_policy_ok(site) == 0) 303 return (FLUSH_STAT_DENY); 304 305 /* 306 * Map site to path and update log. 307 */ 308 site_path = flush_site_to_path((VSTRING *) 0, site); 309 status = flush_add_path(STR(site_path), queue_id); 310 vstring_free(site_path); 311 312 return (status); 313 } 314 315 /* flush_add_path - add record to log */ 316 317 static int flush_add_path(const char *path, const char *queue_id) 318 { 319 const char *myname = "flush_add_path"; 320 VSTREAM *log; 321 322 /* 323 * Sanity check. 324 */ 325 if (!mail_queue_id_ok(path)) 326 return (FLUSH_STAT_BAD); 327 328 /* 329 * Open the logfile or bust. 330 */ 331 if ((log = mail_queue_open(MAIL_QUEUE_FLUSH, path, 332 O_CREAT | O_APPEND | O_WRONLY, 0600)) == 0) 333 msg_fatal("%s: open fast flush logfile %s: %m", myname, path); 334 335 /* 336 * We must lock the logfile, so that we don't lose information due to 337 * concurrent access. If the lock takes too long, the Postfix watchdog 338 * will eventually take care of the problem, but it will take a while. 339 */ 340 if (myflock(vstream_fileno(log), INTERNAL_LOCK, MYFLOCK_OP_EXCLUSIVE) < 0) 341 msg_fatal("%s: lock fast flush logfile %s: %m", myname, path); 342 343 /* 344 * Append the queue ID. With 15 bits of microsecond time, a queue ID is 345 * not recycled often enough for false hits to be a problem. If it does, 346 * then we could add other signature information, such as the file size 347 * in bytes. 348 */ 349 vstream_fprintf(log, "%s\n", queue_id); 350 if (vstream_fflush(log)) 351 msg_warn("write fast flush logfile %s: %m", path); 352 353 /* 354 * Clean up. 355 */ 356 if (myflock(vstream_fileno(log), INTERNAL_LOCK, MYFLOCK_OP_NONE) < 0) 357 msg_fatal("%s: unlock fast flush logfile %s: %m", myname, path); 358 if (vstream_fclose(log) != 0) 359 msg_warn("write fast flush logfile %s: %m", path); 360 361 return (FLUSH_STAT_OK); 362 } 363 364 /* flush_send_service - flush mail queued for site */ 365 366 static int flush_send_service(const char *site, int how) 367 { 368 const char *myname = "flush_send_service"; 369 VSTRING *site_path; 370 int status; 371 372 if (msg_verbose) 373 msg_info("%s: site %s", myname, site); 374 375 /* 376 * If this site is not eligible for logging, deny the request. 377 */ 378 if (flush_policy_ok(site) == 0) 379 return (FLUSH_STAT_DENY); 380 381 /* 382 * Map site name to path name and flush the log. 383 */ 384 site_path = flush_site_to_path((VSTRING *) 0, site); 385 status = flush_send_path(STR(site_path), how); 386 vstring_free(site_path); 387 388 return (status); 389 } 390 391 /* flush_one_file - move one queue file to incoming queue */ 392 393 static int flush_one_file(const char *queue_id, VSTRING *queue_file, 394 struct utimbuf * tbuf, int how) 395 { 396 const char *myname = "flush_one_file"; 397 const char *queue_name; 398 const char *path; 399 400 /* 401 * Some other instance of this program may flush some logfile and may 402 * just have moved this queue file to the incoming queue. 403 */ 404 for (queue_name = MAIL_QUEUE_DEFERRED; /* see below */ ; 405 queue_name = MAIL_QUEUE_INCOMING) { 406 path = mail_queue_path(queue_file, queue_name, queue_id); 407 if (utime(path, tbuf) == 0) 408 break; 409 if (errno != ENOENT) 410 msg_warn("%s: update %s time stamps: %m", myname, path); 411 if (STREQ(queue_name, MAIL_QUEUE_INCOMING)) 412 return (0); 413 } 414 415 /* 416 * With the UNTHROTTLE_AFTER strategy, we leave it up to the queue 417 * manager to unthrottle transports and queues as it reads recipients 418 * from a queue file. We request this unthrottle operation by setting the 419 * group read permission bit. 420 * 421 * Note: we must avoid using chmod(). It is not only slower than fchmod() 422 * but it is also less secure. With chmod(), an attacker could repeatedly 423 * send requests to the flush server and trick it into changing 424 * permissions of non-queue files, by exploiting a race condition. 425 * 426 * We use safe_open() because we don't validate the file content before 427 * modifying the file status. 428 */ 429 if (how & UNTHROTTLE_AFTER) { 430 VSTRING *why; 431 struct stat st; 432 VSTREAM *fp; 433 434 for (why = vstring_alloc(1); /* see below */ ; 435 queue_name = MAIL_QUEUE_INCOMING, 436 path = mail_queue_path(queue_file, queue_name, queue_id)) { 437 if ((fp = safe_open(path, O_RDWR, 0, &st, -1, -1, why)) != 0) 438 break; 439 if (errno != ENOENT) 440 msg_warn("%s: open %s: %s", myname, path, STR(why)); 441 if (errno != ENOENT || STREQ(queue_name, MAIL_QUEUE_INCOMING)) { 442 vstring_free(why); 443 return (0); 444 } 445 } 446 vstring_free(why); 447 if ((st.st_mode & MAIL_QUEUE_STAT_READY) != MAIL_QUEUE_STAT_READY) { 448 (void) vstream_fclose(fp); 449 return (0); 450 } 451 if (fchmod(vstream_fileno(fp), st.st_mode | MAIL_QUEUE_STAT_UNTHROTTLE) < 0) 452 msg_warn("%s: fchmod %s: %m", myname, path); 453 (void) vstream_fclose(fp); 454 } 455 456 /* 457 * Move the file to the incoming queue, if it isn't already there. 458 */ 459 if (STREQ(queue_name, MAIL_QUEUE_INCOMING) == 0 460 && mail_queue_rename(queue_id, queue_name, MAIL_QUEUE_INCOMING) < 0 461 && errno != ENOENT) 462 msg_warn("%s: rename from %s to %s: %m", 463 path, queue_name, MAIL_QUEUE_INCOMING); 464 465 /* 466 * If we got here, we achieved something, so let's claim succes. 467 */ 468 return (1); 469 } 470 471 /* flush_send_path - flush logfile file */ 472 473 static int flush_send_path(const char *path, int how) 474 { 475 const char *myname = "flush_send_path"; 476 VSTRING *queue_id; 477 VSTRING *queue_file; 478 VSTREAM *log; 479 struct utimbuf tbuf; 480 static char qmgr_flush_trigger[] = { 481 QMGR_REQ_FLUSH_DEAD, /* flush dead site/transport cache */ 482 }; 483 static char qmgr_scan_trigger[] = { 484 QMGR_REQ_SCAN_INCOMING, /* scan incoming queue */ 485 }; 486 HTABLE *dup_filter; 487 int count; 488 489 /* 490 * Sanity check. 491 */ 492 if (!mail_queue_id_ok(path)) 493 return (FLUSH_STAT_BAD); 494 495 /* 496 * Open the logfile. If the file does not exist, then there is no queued 497 * mail for this destination. 498 */ 499 if ((log = mail_queue_open(MAIL_QUEUE_FLUSH, path, O_RDWR, 0600)) == 0) { 500 if (errno != ENOENT) 501 msg_fatal("%s: open fast flush logfile %s: %m", myname, path); 502 return (FLUSH_STAT_OK); 503 } 504 505 /* 506 * We must lock the logfile, so that we don't lose information when it is 507 * truncated. Unfortunately, this means that the file can be locked for a 508 * significant amount of time. If things really get stuck the Postfix 509 * watchdog will take care of it. 510 */ 511 if (myflock(vstream_fileno(log), INTERNAL_LOCK, MYFLOCK_OP_EXCLUSIVE) < 0) 512 msg_fatal("%s: lock fast flush logfile %s: %m", myname, path); 513 514 /* 515 * With the UNTHROTTLE_BEFORE strategy, we ask the queue manager to 516 * unthrottle all transports and queues before we move a deferred queue 517 * file to the incoming queue. This minimizes a race condition where the 518 * queue manager seizes a queue file before it knows that we want to 519 * flush that message. 520 * 521 * This reduces the race condition time window to a very small amount (the 522 * flush server does not really know when the queue manager reads its 523 * command fifo). But there is a worse race, where the queue manager 524 * moves a deferred queue file to the active queue before we have a 525 * chance to expedite its delivery. 526 */ 527 if (how & UNTHROTTLE_BEFORE) 528 mail_trigger(MAIL_CLASS_PUBLIC, var_queue_service, 529 qmgr_flush_trigger, sizeof(qmgr_flush_trigger)); 530 531 /* 532 * This is the part that dominates running time: schedule the listed 533 * queue files for delivery by updating their file time stamps and by 534 * moving them from the deferred queue to the incoming queue. This should 535 * take no more than a couple seconds under normal conditions. Filter out 536 * duplicate queue file names to avoid hammering the file system, with 537 * some finite limit on the amount of memory that we are willing to 538 * sacrifice for duplicate filtering. Graceful degradation. 539 * 540 * By moving selected queue files from the deferred queue to the incoming 541 * queue we optimize for the case where most deferred mail is for other 542 * sites. If that assumption does not hold, i.e. all deferred mail is for 543 * the same site, then doing a "fast flush" will cost more disk I/O than 544 * a "slow flush" that delivers the entire deferred queue. This penalty 545 * is only temporary - it will go away after we unite the active queue 546 * and the incoming queue. 547 */ 548 queue_id = vstring_alloc(10); 549 queue_file = vstring_alloc(10); 550 dup_filter = htable_create(10); 551 tbuf.actime = tbuf.modtime = event_time(); 552 for (count = 0; vstring_get_nonl(queue_id, log) != VSTREAM_EOF; count++) { 553 if (!mail_queue_id_ok(STR(queue_id))) { 554 msg_warn("bad queue id \"%.30s...\" in fast flush logfile %s", 555 STR(queue_id), path); 556 continue; 557 } 558 if (dup_filter->used >= FLUSH_DUP_FILTER_SIZE 559 || htable_find(dup_filter, STR(queue_id)) == 0) { 560 if (msg_verbose) 561 msg_info("%s: logfile %s: update queue file %s time stamps", 562 myname, path, STR(queue_id)); 563 if (dup_filter->used <= FLUSH_DUP_FILTER_SIZE) 564 htable_enter(dup_filter, STR(queue_id), 0); 565 count += flush_one_file(STR(queue_id), queue_file, &tbuf, how); 566 } else { 567 if (msg_verbose) 568 msg_info("%s: logfile %s: skip queue file %s as duplicate", 569 myname, path, STR(queue_file)); 570 } 571 } 572 htable_free(dup_filter, (void (*) (char *)) 0); 573 vstring_free(queue_file); 574 vstring_free(queue_id); 575 576 /* 577 * Truncate the fast flush log. 578 */ 579 if (count > 0 && ftruncate(vstream_fileno(log), (off_t) 0) < 0) 580 msg_fatal("%s: truncate fast flush logfile %s: %m", myname, path); 581 582 /* 583 * Workaround for noatime mounts. Use futimes() if available. 584 */ 585 (void) utimes(VSTREAM_PATH(log), (struct timeval *) 0); 586 587 /* 588 * Request delivery and clean up. 589 */ 590 if (myflock(vstream_fileno(log), INTERNAL_LOCK, MYFLOCK_OP_NONE) < 0) 591 msg_fatal("%s: unlock fast flush logfile %s: %m", myname, path); 592 if (vstream_fclose(log) != 0) 593 msg_warn("%s: read fast flush logfile %s: %m", myname, path); 594 if (count > 0) { 595 if (msg_verbose) 596 msg_info("%s: requesting delivery for logfile %s", myname, path); 597 mail_trigger(MAIL_CLASS_PUBLIC, var_queue_service, 598 qmgr_scan_trigger, sizeof(qmgr_scan_trigger)); 599 } 600 return (FLUSH_STAT_OK); 601 } 602 603 /* flush_send_file_service - flush one queue file */ 604 605 static int flush_send_file_service(const char *queue_id) 606 { 607 const char *myname = "flush_send_file_service"; 608 VSTRING *queue_file; 609 struct utimbuf tbuf; 610 static char qmgr_scan_trigger[] = { 611 QMGR_REQ_SCAN_INCOMING, /* scan incoming queue */ 612 }; 613 614 /* 615 * Sanity check. 616 */ 617 if (!mail_queue_id_ok(queue_id)) 618 return (FLUSH_STAT_BAD); 619 620 if (msg_verbose) 621 msg_info("%s: requesting delivery for queue_id %s", myname, queue_id); 622 623 queue_file = vstring_alloc(30); 624 tbuf.actime = tbuf.modtime = event_time(); 625 if (flush_one_file(queue_id, queue_file, &tbuf, UNTHROTTLE_AFTER) > 0) 626 mail_trigger(MAIL_CLASS_PUBLIC, var_queue_service, 627 qmgr_scan_trigger, sizeof(qmgr_scan_trigger)); 628 vstring_free(queue_file); 629 630 return (FLUSH_STAT_OK); 631 } 632 633 /* flush_refresh_service - refresh logfiles beyond some age */ 634 635 static int flush_refresh_service(int max_age) 636 { 637 const char *myname = "flush_refresh_service"; 638 SCAN_DIR *scan; 639 char *site_path; 640 struct stat st; 641 VSTRING *path = vstring_alloc(10); 642 643 scan = scan_dir_open(MAIL_QUEUE_FLUSH); 644 while ((site_path = mail_scan_dir_next(scan)) != 0) { 645 if (!mail_queue_id_ok(site_path)) 646 continue; /* XXX grumble. */ 647 mail_queue_path(path, MAIL_QUEUE_FLUSH, site_path); 648 if (stat(STR(path), &st) < 0) { 649 if (errno != ENOENT) 650 msg_warn("%s: stat %s: %m", myname, STR(path)); 651 else if (msg_verbose) 652 msg_info("%s: %s: %m", myname, STR(path)); 653 continue; 654 } 655 if (st.st_size == 0) { 656 if (st.st_mtime + var_fflush_purge < event_time()) { 657 if (unlink(STR(path)) < 0) 658 msg_warn("remove logfile %s: %m", STR(path)); 659 else if (msg_verbose) 660 msg_info("%s: unlink %s, empty and unchanged for %d days", 661 myname, STR(path), var_fflush_purge / 86400); 662 } else if (msg_verbose) 663 msg_info("%s: skip logfile %s - empty log", myname, site_path); 664 } else if (st.st_atime + max_age < event_time()) { 665 if (msg_verbose) 666 msg_info("%s: flush logfile %s", myname, site_path); 667 flush_send_path(site_path, REFRESH_ONLY); 668 } else { 669 if (msg_verbose) 670 msg_info("%s: skip logfile %s, unread for <%d hours(s) ", 671 myname, site_path, max_age / 3600); 672 } 673 } 674 scan_dir_close(scan); 675 vstring_free(path); 676 677 return (FLUSH_STAT_OK); 678 } 679 680 /* flush_request_receive - receive request */ 681 682 static int flush_request_receive(VSTREAM *client_stream, VSTRING *request) 683 { 684 int count; 685 686 /* 687 * Kluge: choose the protocol depending on the request size. 688 */ 689 if (read_wait(vstream_fileno(client_stream), var_ipc_timeout) < 0) { 690 msg_warn("timeout while waiting for data from %s", 691 VSTREAM_PATH(client_stream)); 692 return (-1); 693 } 694 if ((count = peekfd(vstream_fileno(client_stream))) < 0) { 695 msg_warn("cannot examine read buffer of %s: %m", 696 VSTREAM_PATH(client_stream)); 697 return (-1); 698 } 699 700 /* 701 * Short request: master trigger. Use the string+null protocol. 702 */ 703 if (count <= 2) { 704 if (vstring_get_null(request, client_stream) == VSTREAM_EOF) { 705 msg_warn("end-of-input while reading request from %s: %m", 706 VSTREAM_PATH(client_stream)); 707 return (-1); 708 } 709 } 710 711 /* 712 * Long request: real flush client. Use the attribute list protocol. 713 */ 714 else { 715 if (attr_scan(client_stream, 716 ATTR_FLAG_MORE | ATTR_FLAG_STRICT, 717 ATTR_TYPE_STR, MAIL_ATTR_REQ, request, 718 ATTR_TYPE_END) != 1) { 719 return (-1); 720 } 721 } 722 return (0); 723 } 724 725 /* flush_service - perform service for client */ 726 727 static void flush_service(VSTREAM *client_stream, char *unused_service, 728 char **argv) 729 { 730 VSTRING *request = vstring_alloc(10); 731 VSTRING *site = 0; 732 VSTRING *queue_id = 0; 733 static char wakeup[] = { /* master wakeup request */ 734 TRIGGER_REQ_WAKEUP, 735 0, 736 }; 737 int status = FLUSH_STAT_BAD; 738 739 /* 740 * Sanity check. This service takes no command-line arguments. 741 */ 742 if (argv[0]) 743 msg_fatal("unexpected command-line argument: %s", argv[0]); 744 745 /* 746 * This routine runs whenever a client connects to the UNIX-domain socket 747 * dedicated to the fast flush service. What we see below is a little 748 * protocol to (1) read a request from the client (the name of the site) 749 * and (2) acknowledge that we have received the request. 750 * 751 * All connection-management stuff is handled by the common code in 752 * single_server.c. 753 */ 754 if (flush_request_receive(client_stream, request) == 0) { 755 if (STREQ(STR(request), FLUSH_REQ_ADD)) { 756 site = vstring_alloc(10); 757 queue_id = vstring_alloc(10); 758 if (attr_scan(client_stream, ATTR_FLAG_STRICT, 759 ATTR_TYPE_STR, MAIL_ATTR_SITE, site, 760 ATTR_TYPE_STR, MAIL_ATTR_QUEUEID, queue_id, 761 ATTR_TYPE_END) == 2 762 && mail_queue_id_ok(STR(queue_id))) 763 status = flush_add_service(lowercase(STR(site)), STR(queue_id)); 764 attr_print(client_stream, ATTR_FLAG_NONE, 765 ATTR_TYPE_INT, MAIL_ATTR_STATUS, status, 766 ATTR_TYPE_END); 767 } else if (STREQ(STR(request), FLUSH_REQ_SEND_SITE)) { 768 site = vstring_alloc(10); 769 if (attr_scan(client_stream, ATTR_FLAG_STRICT, 770 ATTR_TYPE_STR, MAIL_ATTR_SITE, site, 771 ATTR_TYPE_END) == 1) 772 status = flush_send_service(lowercase(STR(site)), 773 UNTHROTTLE_BEFORE); 774 attr_print(client_stream, ATTR_FLAG_NONE, 775 ATTR_TYPE_INT, MAIL_ATTR_STATUS, status, 776 ATTR_TYPE_END); 777 } else if (STREQ(STR(request), FLUSH_REQ_SEND_FILE)) { 778 queue_id = vstring_alloc(10); 779 if (attr_scan(client_stream, ATTR_FLAG_STRICT, 780 ATTR_TYPE_STR, MAIL_ATTR_QUEUEID, queue_id, 781 ATTR_TYPE_END) == 1) 782 status = flush_send_file_service(STR(queue_id)); 783 attr_print(client_stream, ATTR_FLAG_NONE, 784 ATTR_TYPE_INT, MAIL_ATTR_STATUS, status, 785 ATTR_TYPE_END); 786 } else if (STREQ(STR(request), FLUSH_REQ_REFRESH) 787 || STREQ(STR(request), wakeup)) { 788 attr_print(client_stream, ATTR_FLAG_NONE, 789 ATTR_TYPE_INT, MAIL_ATTR_STATUS, FLUSH_STAT_OK, 790 ATTR_TYPE_END); 791 vstream_fflush(client_stream); 792 (void) flush_refresh_service(var_fflush_refresh); 793 } else if (STREQ(STR(request), FLUSH_REQ_PURGE)) { 794 attr_print(client_stream, ATTR_FLAG_NONE, 795 ATTR_TYPE_INT, MAIL_ATTR_STATUS, FLUSH_STAT_OK, 796 ATTR_TYPE_END); 797 vstream_fflush(client_stream); 798 (void) flush_refresh_service(0); 799 } 800 } else 801 attr_print(client_stream, ATTR_FLAG_NONE, 802 ATTR_TYPE_INT, MAIL_ATTR_STATUS, status, 803 ATTR_TYPE_END); 804 vstring_free(request); 805 if (site) 806 vstring_free(site); 807 if (queue_id) 808 vstring_free(queue_id); 809 } 810 811 /* pre_jail_init - pre-jail initialization */ 812 813 static void pre_jail_init(char *unused_name, char **unused_argv) 814 { 815 flush_domains = domain_list_init(match_parent_style(VAR_FFLUSH_DOMAINS), 816 var_fflush_domains); 817 } 818 819 MAIL_VERSION_STAMP_DECLARE; 820 821 /* main - pass control to the single-threaded skeleton */ 822 823 int main(int argc, char **argv) 824 { 825 static const CONFIG_TIME_TABLE time_table[] = { 826 VAR_FFLUSH_REFRESH, DEF_FFLUSH_REFRESH, &var_fflush_refresh, 1, 0, 827 VAR_FFLUSH_PURGE, DEF_FFLUSH_PURGE, &var_fflush_purge, 1, 0, 828 0, 829 }; 830 831 /* 832 * Fingerprint executables and core dumps. 833 */ 834 MAIL_VERSION_STAMP_ALLOCATE; 835 836 single_server_main(argc, argv, flush_service, 837 MAIL_SERVER_TIME_TABLE, time_table, 838 MAIL_SERVER_PRE_INIT, pre_jail_init, 839 MAIL_SERVER_UNLIMITED, 840 0); 841 } 842