1 /* $NetBSD: flush.c,v 1.2 2017/02/14 01:16:45 christos 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 /* A list of Postfix features where the pattern "example.com" also 108 /* matches subdomains of example.com, 109 /* instead of requiring an explicit ".example.com" pattern. 110 /* .IP "\fBprocess_id (read-only)\fR" 111 /* The process ID of a Postfix command or daemon process. 112 /* .IP "\fBprocess_name (read-only)\fR" 113 /* The process name of a Postfix command or daemon process. 114 /* .IP "\fBqueue_directory (see 'postconf -d' output)\fR" 115 /* The location of the Postfix top-level queue directory. 116 /* .IP "\fBsyslog_facility (mail)\fR" 117 /* The syslog facility of Postfix logging. 118 /* .IP "\fBsyslog_name (see 'postconf -d' output)\fR" 119 /* The mail system name that is prepended to the process name in syslog 120 /* records, so that "smtpd" becomes, for example, "postfix/smtpd". 121 /* FILES 122 /* /var/spool/postfix/flush, "fast flush" logfiles. 123 /* SEE ALSO 124 /* smtpd(8), SMTP server 125 /* qmgr(8), queue manager 126 /* postconf(5), configuration parameters 127 /* master(5), generic daemon options 128 /* master(8), process manager 129 /* syslogd(8), system logging 130 /* README FILES 131 /* .ad 132 /* .fi 133 /* Use "\fBpostconf readme_directory\fR" or 134 /* "\fBpostconf html_directory\fR" to locate this information. 135 /* .na 136 /* .nf 137 /* ETRN_README, Postfix ETRN howto 138 /* LICENSE 139 /* .ad 140 /* .fi 141 /* The Secure Mailer license must be distributed with this software. 142 /* HISTORY 143 /* This service was introduced with Postfix version 1.0. 144 /* AUTHOR(S) 145 /* Wietse Venema 146 /* IBM T.J. Watson Research 147 /* P.O. Box 704 148 /* Yorktown Heights, NY 10598, USA 149 /* 150 /* Wietse Venema 151 /* Google, Inc. 152 /* 111 8th Avenue 153 /* New York, NY 10011, USA 154 /*--*/ 155 156 /* System library. */ 157 158 #include <sys_defs.h> 159 #include <sys/stat.h> 160 #include <sys/time.h> 161 #include <unistd.h> 162 #include <stdlib.h> 163 #include <utime.h> 164 #include <errno.h> 165 #include <ctype.h> 166 #include <string.h> 167 168 /* Utility library. */ 169 170 #include <msg.h> 171 #include <events.h> 172 #include <vstream.h> 173 #include <vstring.h> 174 #include <vstring_vstream.h> 175 #include <myflock.h> 176 #include <htable.h> 177 #include <dict.h> 178 #include <scan_dir.h> 179 #include <stringops.h> 180 #include <safe_open.h> 181 #include <warn_stat.h> 182 #include <midna_domain.h> 183 184 /* Global library. */ 185 186 #include <mail_params.h> 187 #include <mail_version.h> 188 #include <mail_queue.h> 189 #include <mail_proto.h> 190 #include <mail_flush.h> 191 #include <flush_clnt.h> 192 #include <mail_conf.h> 193 #include <mail_scan_dir.h> 194 #include <maps.h> 195 #include <domain_list.h> 196 #include <match_parent_style.h> 197 198 /* Single server skeleton. */ 199 200 #include <mail_server.h> 201 202 /* Application-specific. */ 203 204 /* 205 * Tunable parameters. The fast_flush_domains parameter is not defined here, 206 * because it is also used by the global library, and therefore is owned by 207 * the library. 208 */ 209 int var_fflush_refresh; 210 int var_fflush_purge; 211 212 /* 213 * Flush policy stuff. 214 */ 215 static DOMAIN_LIST *flush_domains; 216 217 /* 218 * Some hard-wired policy: how many queue IDs we remember while we're 219 * flushing a logfile (duplicate elimination). Sites with 1000+ emails 220 * queued should arrange for permanent connectivity. 221 */ 222 #define FLUSH_DUP_FILTER_SIZE 10000 /* graceful degradation */ 223 224 /* 225 * Silly little macros. 226 */ 227 #define STR(x) vstring_str(x) 228 #define STREQ(x,y) ((x) == (y) || strcmp(x,y) == 0) 229 230 /* 231 * Forward declarations resulting from breaking up routines according to 232 * name space: domain names versus safe-to-use pathnames. 233 */ 234 static int flush_add_path(const char *, const char *); 235 static int flush_send_path(const char *, int); 236 237 /* 238 * Do we only refresh the per-destination logfile, or do we really request 239 * mail delivery as if someone sent ETRN? If the latter, we must override 240 * information about unavailable hosts or unavailable transports. 241 * 242 * When selectively flushing deferred mail, we need to override the queue 243 * manager's "dead destination" information and unthrottle transports and 244 * queues. There are two options: 245 * 246 * - Unthrottle all transports and queues before we move mail to the incoming 247 * queue. This is less accurate, but has the advantage when flushing lots of 248 * mail, because Postfix can skip delivery of flushed messages after it 249 * discovers that a destination is (still) unavailable. 250 * 251 * - Unthrottle some transports and queues after the queue manager moves mail 252 * to the active queue. This is more accurate, but has the disadvantage when 253 * flushing lots of mail, because Postfix cannot skip delivery of flushed 254 * messages after it discovers that a destination is (still) unavailable. 255 */ 256 #define REFRESH_ONLY 0 257 #define UNTHROTTLE_BEFORE (1<<0) 258 #define UNTHROTTLE_AFTER (1<<1) 259 260 /* flush_site_to_path - convert domain or [addr] to harmless string */ 261 262 static VSTRING *flush_site_to_path(VSTRING *path, const char *site) 263 { 264 const char *ptr; 265 int ch; 266 267 /* 268 * Convert the name to ASCII, so that we don't to end up with non-ASCII 269 * names in the file system. The IDNA library functions fold case. 270 */ 271 #ifndef NO_EAI 272 if ((site = midna_domain_to_ascii(site)) == 0) 273 return (0); 274 #endif 275 276 /* 277 * Allocate buffer on the fly; caller still needs to clean up. 278 */ 279 if (path == 0) 280 path = vstring_alloc(10); 281 282 /* 283 * Mask characters that could upset the name-to-queue-file mapping code. 284 */ 285 for (ptr = site; (ch = *(unsigned const char *) ptr) != 0; ptr++) 286 if (ISALNUM(ch)) 287 VSTRING_ADDCH(path, tolower(ch)); 288 else 289 VSTRING_ADDCH(path, '_'); 290 VSTRING_TERMINATE(path); 291 292 if (msg_verbose) 293 msg_info("site %s to path %s", site, STR(path)); 294 295 return (path); 296 } 297 298 /* flush_add_service - append queue ID to per-site fast flush logfile */ 299 300 static int flush_add_service(const char *site, const char *queue_id) 301 { 302 const char *myname = "flush_add_service"; 303 VSTRING *site_path; 304 int status; 305 306 if (msg_verbose) 307 msg_info("%s: site %s queue_id %s", myname, site, queue_id); 308 309 /* 310 * If this site is not eligible for logging, deny the request. 311 */ 312 if (domain_list_match(flush_domains, site) == 0) 313 return (flush_domains->error ? FLUSH_STAT_FAIL : FLUSH_STAT_DENY); 314 315 /* 316 * Map site to path and update log. 317 */ 318 if ((site_path = flush_site_to_path((VSTRING *) 0, site)) == 0) 319 return (FLUSH_STAT_DENY); 320 status = flush_add_path(STR(site_path), queue_id); 321 vstring_free(site_path); 322 323 return (status); 324 } 325 326 /* flush_add_path - add record to log */ 327 328 static int flush_add_path(const char *path, const char *queue_id) 329 { 330 const char *myname = "flush_add_path"; 331 VSTREAM *log; 332 333 /* 334 * Sanity check. 335 */ 336 if (!mail_queue_id_ok(path)) 337 return (FLUSH_STAT_BAD); 338 339 /* 340 * Open the logfile or bust. 341 */ 342 if ((log = mail_queue_open(MAIL_QUEUE_FLUSH, path, 343 O_CREAT | O_APPEND | O_WRONLY, 0600)) == 0) 344 msg_fatal("%s: open fast flush logfile %s: %m", myname, path); 345 346 /* 347 * We must lock the logfile, so that we don't lose information due to 348 * concurrent access. If the lock takes too long, the Postfix watchdog 349 * will eventually take care of the problem, but it will take a while. 350 */ 351 if (myflock(vstream_fileno(log), INTERNAL_LOCK, MYFLOCK_OP_EXCLUSIVE) < 0) 352 msg_fatal("%s: lock fast flush logfile %s: %m", myname, path); 353 354 /* 355 * Append the queue ID. With 15 bits of microsecond time, a queue ID is 356 * not recycled often enough for false hits to be a problem. If it does, 357 * then we could add other signature information, such as the file size 358 * in bytes. 359 */ 360 vstream_fprintf(log, "%s\n", queue_id); 361 if (vstream_fflush(log)) 362 msg_warn("write fast flush logfile %s: %m", path); 363 364 /* 365 * Clean up. 366 */ 367 if (myflock(vstream_fileno(log), INTERNAL_LOCK, MYFLOCK_OP_NONE) < 0) 368 msg_fatal("%s: unlock fast flush logfile %s: %m", myname, path); 369 if (vstream_fclose(log) != 0) 370 msg_warn("write fast flush logfile %s: %m", path); 371 372 return (FLUSH_STAT_OK); 373 } 374 375 /* flush_send_service - flush mail queued for site */ 376 377 static int flush_send_service(const char *site, int how) 378 { 379 const char *myname = "flush_send_service"; 380 VSTRING *site_path; 381 int status; 382 383 if (msg_verbose) 384 msg_info("%s: site %s", myname, site); 385 386 /* 387 * If this site is not eligible for logging, deny the request. 388 */ 389 if (domain_list_match(flush_domains, site) == 0) 390 return (flush_domains->error ? FLUSH_STAT_FAIL : FLUSH_STAT_DENY); 391 392 /* 393 * Map site name to path name and flush the log. 394 */ 395 if ((site_path = flush_site_to_path((VSTRING *) 0, site)) == 0) 396 return (FLUSH_STAT_DENY); 397 status = flush_send_path(STR(site_path), how); 398 vstring_free(site_path); 399 400 return (status); 401 } 402 403 /* flush_one_file - move one queue file to incoming queue */ 404 405 static int flush_one_file(const char *queue_id, VSTRING *queue_file, 406 struct utimbuf * tbuf, int how) 407 { 408 const char *myname = "flush_one_file"; 409 const char *queue_name; 410 const char *path; 411 412 /* 413 * Some other instance of this program may flush some logfile and may 414 * just have moved this queue file to the incoming queue. 415 */ 416 for (queue_name = MAIL_QUEUE_DEFERRED; /* see below */ ; 417 queue_name = MAIL_QUEUE_INCOMING) { 418 path = mail_queue_path(queue_file, queue_name, queue_id); 419 if (utime(path, tbuf) == 0) 420 break; 421 if (errno != ENOENT) 422 msg_warn("%s: update %s time stamps: %m", myname, path); 423 if (STREQ(queue_name, MAIL_QUEUE_INCOMING)) 424 return (0); 425 } 426 427 /* 428 * With the UNTHROTTLE_AFTER strategy, we leave it up to the queue 429 * manager to unthrottle transports and queues as it reads recipients 430 * from a queue file. We request this unthrottle operation by setting the 431 * group read permission bit. 432 * 433 * Note: we must avoid using chmod(). It is not only slower than fchmod() 434 * but it is also less secure. With chmod(), an attacker could repeatedly 435 * send requests to the flush server and trick it into changing 436 * permissions of non-queue files, by exploiting a race condition. 437 * 438 * We use safe_open() because we don't validate the file content before 439 * modifying the file status. 440 */ 441 if (how & UNTHROTTLE_AFTER) { 442 VSTRING *why; 443 struct stat st; 444 VSTREAM *fp; 445 446 for (why = vstring_alloc(1); /* see below */ ; 447 queue_name = MAIL_QUEUE_INCOMING, 448 path = mail_queue_path(queue_file, queue_name, queue_id)) { 449 if ((fp = safe_open(path, O_RDWR, 0, &st, -1, -1, why)) != 0) 450 break; 451 if (errno != ENOENT) 452 msg_warn("%s: open %s: %s", myname, path, STR(why)); 453 if (errno != ENOENT || STREQ(queue_name, MAIL_QUEUE_INCOMING)) { 454 vstring_free(why); 455 return (0); 456 } 457 } 458 vstring_free(why); 459 if ((st.st_mode & MAIL_QUEUE_STAT_READY) != MAIL_QUEUE_STAT_READY) { 460 (void) vstream_fclose(fp); 461 return (0); 462 } 463 if (fchmod(vstream_fileno(fp), st.st_mode | MAIL_QUEUE_STAT_UNTHROTTLE) < 0) 464 msg_warn("%s: fchmod %s: %m", myname, path); 465 (void) vstream_fclose(fp); 466 } 467 468 /* 469 * Move the file to the incoming queue, if it isn't already there. 470 */ 471 if (STREQ(queue_name, MAIL_QUEUE_INCOMING) == 0 472 && mail_queue_rename(queue_id, queue_name, MAIL_QUEUE_INCOMING) < 0 473 && errno != ENOENT) 474 msg_warn("%s: rename from %s to %s: %m", 475 path, queue_name, MAIL_QUEUE_INCOMING); 476 477 /* 478 * If we got here, we achieved something, so let's claim succes. 479 */ 480 return (1); 481 } 482 483 /* flush_send_path - flush logfile file */ 484 485 static int flush_send_path(const char *path, int how) 486 { 487 const char *myname = "flush_send_path"; 488 VSTRING *queue_id; 489 VSTRING *queue_file; 490 VSTREAM *log; 491 struct utimbuf tbuf; 492 static char qmgr_flush_trigger[] = { 493 QMGR_REQ_FLUSH_DEAD, /* flush dead site/transport cache */ 494 }; 495 static char qmgr_scan_trigger[] = { 496 QMGR_REQ_SCAN_INCOMING, /* scan incoming queue */ 497 }; 498 HTABLE *dup_filter; 499 int count; 500 501 /* 502 * Sanity check. 503 */ 504 if (!mail_queue_id_ok(path)) 505 return (FLUSH_STAT_BAD); 506 507 /* 508 * Open the logfile. If the file does not exist, then there is no queued 509 * mail for this destination. 510 */ 511 if ((log = mail_queue_open(MAIL_QUEUE_FLUSH, path, O_RDWR, 0600)) == 0) { 512 if (errno != ENOENT) 513 msg_fatal("%s: open fast flush logfile %s: %m", myname, path); 514 return (FLUSH_STAT_OK); 515 } 516 517 /* 518 * We must lock the logfile, so that we don't lose information when it is 519 * truncated. Unfortunately, this means that the file can be locked for a 520 * significant amount of time. If things really get stuck the Postfix 521 * watchdog will take care of it. 522 */ 523 if (myflock(vstream_fileno(log), INTERNAL_LOCK, MYFLOCK_OP_EXCLUSIVE) < 0) 524 msg_fatal("%s: lock fast flush logfile %s: %m", myname, path); 525 526 /* 527 * With the UNTHROTTLE_BEFORE strategy, we ask the queue manager to 528 * unthrottle all transports and queues before we move a deferred queue 529 * file to the incoming queue. This minimizes a race condition where the 530 * queue manager seizes a queue file before it knows that we want to 531 * flush that message. 532 * 533 * This reduces the race condition time window to a very small amount (the 534 * flush server does not really know when the queue manager reads its 535 * command fifo). But there is a worse race, where the queue manager 536 * moves a deferred queue file to the active queue before we have a 537 * chance to expedite its delivery. 538 */ 539 if (how & UNTHROTTLE_BEFORE) 540 mail_trigger(MAIL_CLASS_PUBLIC, var_queue_service, 541 qmgr_flush_trigger, sizeof(qmgr_flush_trigger)); 542 543 /* 544 * This is the part that dominates running time: schedule the listed 545 * queue files for delivery by updating their file time stamps and by 546 * moving them from the deferred queue to the incoming queue. This should 547 * take no more than a couple seconds under normal conditions. Filter out 548 * duplicate queue file names to avoid hammering the file system, with 549 * some finite limit on the amount of memory that we are willing to 550 * sacrifice for duplicate filtering. Graceful degradation. 551 * 552 * By moving selected queue files from the deferred queue to the incoming 553 * queue we optimize for the case where most deferred mail is for other 554 * sites. If that assumption does not hold, i.e. all deferred mail is for 555 * the same site, then doing a "fast flush" will cost more disk I/O than 556 * a "slow flush" that delivers the entire deferred queue. This penalty 557 * is only temporary - it will go away after we unite the active queue 558 * and the incoming queue. 559 */ 560 queue_id = vstring_alloc(10); 561 queue_file = vstring_alloc(10); 562 dup_filter = htable_create(10); 563 tbuf.actime = tbuf.modtime = event_time(); 564 for (count = 0; vstring_get_nonl(queue_id, log) != VSTREAM_EOF; count++) { 565 if (!mail_queue_id_ok(STR(queue_id))) { 566 msg_warn("bad queue id \"%.30s...\" in fast flush logfile %s", 567 STR(queue_id), path); 568 continue; 569 } 570 if (dup_filter->used >= FLUSH_DUP_FILTER_SIZE 571 || htable_find(dup_filter, STR(queue_id)) == 0) { 572 if (msg_verbose) 573 msg_info("%s: logfile %s: update queue file %s time stamps", 574 myname, path, STR(queue_id)); 575 if (dup_filter->used <= FLUSH_DUP_FILTER_SIZE) 576 htable_enter(dup_filter, STR(queue_id), 0); 577 count += flush_one_file(STR(queue_id), queue_file, &tbuf, how); 578 } else { 579 if (msg_verbose) 580 msg_info("%s: logfile %s: skip queue file %s as duplicate", 581 myname, path, STR(queue_file)); 582 } 583 } 584 htable_free(dup_filter, (void (*) (void *)) 0); 585 vstring_free(queue_file); 586 vstring_free(queue_id); 587 588 /* 589 * Truncate the fast flush log. 590 */ 591 if (count > 0 && ftruncate(vstream_fileno(log), (off_t) 0) < 0) 592 msg_fatal("%s: truncate fast flush logfile %s: %m", myname, path); 593 594 /* 595 * Workaround for noatime mounts. Use futimes() if available. 596 */ 597 (void) utimes(VSTREAM_PATH(log), (struct timeval *) 0); 598 599 /* 600 * Request delivery and clean up. 601 */ 602 if (myflock(vstream_fileno(log), INTERNAL_LOCK, MYFLOCK_OP_NONE) < 0) 603 msg_fatal("%s: unlock fast flush logfile %s: %m", myname, path); 604 if (vstream_fclose(log) != 0) 605 msg_warn("%s: read fast flush logfile %s: %m", myname, path); 606 if (count > 0) { 607 if (msg_verbose) 608 msg_info("%s: requesting delivery for logfile %s", myname, path); 609 mail_trigger(MAIL_CLASS_PUBLIC, var_queue_service, 610 qmgr_scan_trigger, sizeof(qmgr_scan_trigger)); 611 } 612 return (FLUSH_STAT_OK); 613 } 614 615 /* flush_send_file_service - flush one queue file */ 616 617 static int flush_send_file_service(const char *queue_id) 618 { 619 const char *myname = "flush_send_file_service"; 620 VSTRING *queue_file; 621 struct utimbuf tbuf; 622 static char qmgr_scan_trigger[] = { 623 QMGR_REQ_SCAN_INCOMING, /* scan incoming queue */ 624 }; 625 626 /* 627 * Sanity check. 628 */ 629 if (!mail_queue_id_ok(queue_id)) 630 return (FLUSH_STAT_BAD); 631 632 if (msg_verbose) 633 msg_info("%s: requesting delivery for queue_id %s", myname, queue_id); 634 635 queue_file = vstring_alloc(30); 636 tbuf.actime = tbuf.modtime = event_time(); 637 if (flush_one_file(queue_id, queue_file, &tbuf, UNTHROTTLE_AFTER) > 0) 638 mail_trigger(MAIL_CLASS_PUBLIC, var_queue_service, 639 qmgr_scan_trigger, sizeof(qmgr_scan_trigger)); 640 vstring_free(queue_file); 641 642 return (FLUSH_STAT_OK); 643 } 644 645 /* flush_refresh_service - refresh logfiles beyond some age */ 646 647 static int flush_refresh_service(int max_age) 648 { 649 const char *myname = "flush_refresh_service"; 650 SCAN_DIR *scan; 651 char *site_path; 652 struct stat st; 653 VSTRING *path = vstring_alloc(10); 654 655 scan = scan_dir_open(MAIL_QUEUE_FLUSH); 656 while ((site_path = mail_scan_dir_next(scan)) != 0) { 657 if (!mail_queue_id_ok(site_path)) 658 continue; /* XXX grumble. */ 659 mail_queue_path(path, MAIL_QUEUE_FLUSH, site_path); 660 if (stat(STR(path), &st) < 0) { 661 if (errno != ENOENT) 662 msg_warn("%s: stat %s: %m", myname, STR(path)); 663 else if (msg_verbose) 664 msg_info("%s: %s: %m", myname, STR(path)); 665 continue; 666 } 667 if (st.st_size == 0) { 668 if (st.st_mtime + var_fflush_purge < event_time()) { 669 if (unlink(STR(path)) < 0) 670 msg_warn("remove logfile %s: %m", STR(path)); 671 else if (msg_verbose) 672 msg_info("%s: unlink %s, empty and unchanged for %d days", 673 myname, STR(path), var_fflush_purge / 86400); 674 } else if (msg_verbose) 675 msg_info("%s: skip logfile %s - empty log", myname, site_path); 676 } else if (st.st_atime + max_age < event_time()) { 677 if (msg_verbose) 678 msg_info("%s: flush logfile %s", myname, site_path); 679 flush_send_path(site_path, REFRESH_ONLY); 680 } else { 681 if (msg_verbose) 682 msg_info("%s: skip logfile %s, unread for <%d hours(s) ", 683 myname, site_path, max_age / 3600); 684 } 685 } 686 scan_dir_close(scan); 687 vstring_free(path); 688 689 return (FLUSH_STAT_OK); 690 } 691 692 /* flush_request_receive - receive request */ 693 694 static int flush_request_receive(VSTREAM *client_stream, VSTRING *request) 695 { 696 int count; 697 698 /* 699 * Kluge: choose the protocol depending on the request size. 700 */ 701 if (read_wait(vstream_fileno(client_stream), var_ipc_timeout) < 0) { 702 msg_warn("timeout while waiting for data from %s", 703 VSTREAM_PATH(client_stream)); 704 return (-1); 705 } 706 if ((count = peekfd(vstream_fileno(client_stream))) < 0) { 707 msg_warn("cannot examine read buffer of %s: %m", 708 VSTREAM_PATH(client_stream)); 709 return (-1); 710 } 711 712 /* 713 * Short request: master trigger. Use the string+null protocol. 714 */ 715 if (count <= 2) { 716 if (vstring_get_null(request, client_stream) == VSTREAM_EOF) { 717 msg_warn("end-of-input while reading request from %s: %m", 718 VSTREAM_PATH(client_stream)); 719 return (-1); 720 } 721 } 722 723 /* 724 * Long request: real flush client. Use the attribute list protocol. 725 */ 726 else { 727 if (attr_scan(client_stream, 728 ATTR_FLAG_MORE | ATTR_FLAG_STRICT, 729 RECV_ATTR_STR(MAIL_ATTR_REQ, request), 730 ATTR_TYPE_END) != 1) { 731 return (-1); 732 } 733 } 734 return (0); 735 } 736 737 /* flush_service - perform service for client */ 738 739 static void flush_service(VSTREAM *client_stream, char *unused_service, 740 char **argv) 741 { 742 VSTRING *request = vstring_alloc(10); 743 VSTRING *site = 0; 744 VSTRING *queue_id = 0; 745 static char wakeup[] = { /* master wakeup request */ 746 TRIGGER_REQ_WAKEUP, 747 0, 748 }; 749 int status = FLUSH_STAT_BAD; 750 751 /* 752 * Sanity check. This service takes no command-line arguments. 753 */ 754 if (argv[0]) 755 msg_fatal("unexpected command-line argument: %s", argv[0]); 756 757 /* 758 * This routine runs whenever a client connects to the UNIX-domain socket 759 * dedicated to the fast flush service. What we see below is a little 760 * protocol to (1) read a request from the client (the name of the site) 761 * and (2) acknowledge that we have received the request. 762 * 763 * All connection-management stuff is handled by the common code in 764 * single_server.c. 765 */ 766 if (flush_request_receive(client_stream, request) == 0) { 767 if (STREQ(STR(request), FLUSH_REQ_ADD)) { 768 site = vstring_alloc(10); 769 queue_id = vstring_alloc(10); 770 if (attr_scan(client_stream, ATTR_FLAG_STRICT, 771 RECV_ATTR_STR(MAIL_ATTR_SITE, site), 772 RECV_ATTR_STR(MAIL_ATTR_QUEUEID, queue_id), 773 ATTR_TYPE_END) == 2 774 && mail_queue_id_ok(STR(queue_id))) 775 status = flush_add_service(STR(site), STR(queue_id)); 776 attr_print(client_stream, ATTR_FLAG_NONE, 777 SEND_ATTR_INT(MAIL_ATTR_STATUS, status), 778 ATTR_TYPE_END); 779 } else if (STREQ(STR(request), FLUSH_REQ_SEND_SITE)) { 780 site = vstring_alloc(10); 781 if (attr_scan(client_stream, ATTR_FLAG_STRICT, 782 RECV_ATTR_STR(MAIL_ATTR_SITE, site), 783 ATTR_TYPE_END) == 1) 784 status = flush_send_service(STR(site), UNTHROTTLE_BEFORE); 785 attr_print(client_stream, ATTR_FLAG_NONE, 786 SEND_ATTR_INT(MAIL_ATTR_STATUS, status), 787 ATTR_TYPE_END); 788 } else if (STREQ(STR(request), FLUSH_REQ_SEND_FILE)) { 789 queue_id = vstring_alloc(10); 790 if (attr_scan(client_stream, ATTR_FLAG_STRICT, 791 RECV_ATTR_STR(MAIL_ATTR_QUEUEID, queue_id), 792 ATTR_TYPE_END) == 1) 793 status = flush_send_file_service(STR(queue_id)); 794 attr_print(client_stream, ATTR_FLAG_NONE, 795 SEND_ATTR_INT(MAIL_ATTR_STATUS, status), 796 ATTR_TYPE_END); 797 } else if (STREQ(STR(request), FLUSH_REQ_REFRESH) 798 || STREQ(STR(request), wakeup)) { 799 attr_print(client_stream, ATTR_FLAG_NONE, 800 SEND_ATTR_INT(MAIL_ATTR_STATUS, FLUSH_STAT_OK), 801 ATTR_TYPE_END); 802 vstream_fflush(client_stream); 803 (void) flush_refresh_service(var_fflush_refresh); 804 } else if (STREQ(STR(request), FLUSH_REQ_PURGE)) { 805 attr_print(client_stream, ATTR_FLAG_NONE, 806 SEND_ATTR_INT(MAIL_ATTR_STATUS, FLUSH_STAT_OK), 807 ATTR_TYPE_END); 808 vstream_fflush(client_stream); 809 (void) flush_refresh_service(0); 810 } 811 } else 812 attr_print(client_stream, ATTR_FLAG_NONE, 813 SEND_ATTR_INT(MAIL_ATTR_STATUS, status), 814 ATTR_TYPE_END); 815 vstring_free(request); 816 if (site) 817 vstring_free(site); 818 if (queue_id) 819 vstring_free(queue_id); 820 } 821 822 /* pre_jail_init - pre-jail initialization */ 823 824 static void pre_jail_init(char *unused_name, char **unused_argv) 825 { 826 flush_domains = domain_list_init(VAR_FFLUSH_DOMAINS, MATCH_FLAG_RETURN 827 | match_parent_style(VAR_FFLUSH_DOMAINS), 828 var_fflush_domains); 829 } 830 831 MAIL_VERSION_STAMP_DECLARE; 832 833 /* main - pass control to the single-threaded skeleton */ 834 835 int main(int argc, char **argv) 836 { 837 static const CONFIG_TIME_TABLE time_table[] = { 838 VAR_FFLUSH_REFRESH, DEF_FFLUSH_REFRESH, &var_fflush_refresh, 1, 0, 839 VAR_FFLUSH_PURGE, DEF_FFLUSH_PURGE, &var_fflush_purge, 1, 0, 840 0, 841 }; 842 843 /* 844 * Fingerprint executables and core dumps. 845 */ 846 MAIL_VERSION_STAMP_ALLOCATE; 847 848 single_server_main(argc, argv, flush_service, 849 CA_MAIL_SERVER_TIME_TABLE(time_table), 850 CA_MAIL_SERVER_PRE_INIT(pre_jail_init), 851 CA_MAIL_SERVER_UNLIMITED, 852 0); 853 } 854