1 /* $NetBSD: trigger_server.c,v 1.2 2017/02/14 01:16:45 christos Exp $ */ 2 3 /*++ 4 /* NAME 5 /* trigger_server 3 6 /* SUMMARY 7 /* skeleton triggered mail subsystem 8 /* SYNOPSIS 9 /* #include <mail_server.h> 10 /* 11 /* NORETURN trigger_server_main(argc, argv, service, key, value, ...) 12 /* int argc; 13 /* char **argv; 14 /* void (*service)(char *buf, int len, char *service_name, char **argv); 15 /* int key; 16 /* DESCRIPTION 17 /* This module implements a skeleton for triggered 18 /* mail subsystems: mail subsystem programs that wake up on 19 /* client request and perform some activity without further 20 /* client interaction. This module supports local IPC via FIFOs 21 /* and via UNIX-domain sockets. The resulting program expects to be 22 /* run from the \fBmaster\fR process. 23 /* 24 /* trigger_server_main() is the skeleton entry point. It should be 25 /* called from the application main program. The skeleton does the 26 /* generic command-line options processing, initialization of 27 /* configurable parameters, and connection management. 28 /* The skeleton never returns. 29 /* 30 /* Arguments: 31 /* .IP "void (*service)(char *buf, int len, char *service_name, char **argv)" 32 /* A pointer to a function that is called by the skeleton each time 33 /* a client connects to the program's service port. The function is 34 /* run after the program has irrevocably dropped its privileges. 35 /* The buffer argument specifies the data read from the trigger port; 36 /* this data corresponds to one or more trigger requests. 37 /* The len argument specifies how much client data is available. 38 /* The maximal size of the buffer is specified via the 39 /* TRIGGER_BUF_SIZE manifest constant. 40 /* The service name argument corresponds to the service name in the 41 /* master.cf file. 42 /* The argv argument specifies command-line arguments left over 43 /* after options processing. 44 /* The \fBserver\fR argument provides the following information: 45 /* .PP 46 /* Optional arguments are specified as a null-terminated list 47 /* with macros that have zero or more arguments: 48 /* .IP "CA_MAIL_SERVER_INT_TABLE(CONFIG_INT_TABLE *)" 49 /* A table with configurable parameters, to be loaded from the 50 /* global Postfix configuration file. Tables are loaded in the 51 /* order as specified, and multiple instances of the same type 52 /* are allowed. 53 /* .IP "CA_MAIL_SERVER_LONG_TABLE(CONFIG_LONG_TABLE *)" 54 /* A table with configurable parameters, to be loaded from the 55 /* global Postfix configuration file. Tables are loaded in the 56 /* order as specified, and multiple instances of the same type 57 /* are allowed. 58 /* .IP "CA_MAIL_SERVER_STR_TABLE(CONFIG_STR_TABLE *)" 59 /* A table with configurable parameters, to be loaded from the 60 /* global Postfix configuration file. Tables are loaded in the 61 /* order as specified, and multiple instances of the same type 62 /* are allowed. 63 /* .IP "CA_MAIL_SERVER_BOOL_TABLE(CONFIG_BOOL_TABLE *)" 64 /* A table with configurable parameters, to be loaded from the 65 /* global Postfix configuration file. Tables are loaded in the 66 /* order as specified, and multiple instances of the same type 67 /* are allowed. 68 /* .IP "CA_MAIL_SERVER_TIME_TABLE(CONFIG_TIME_TABLE *)" 69 /* A table with configurable parameters, to be loaded from the 70 /* global Postfix configuration file. Tables are loaded in the 71 /* order as specified, and multiple instances of the same type 72 /* are allowed. 73 /* .IP "CA_MAIL_SERVER_RAW_TABLE(CONFIG_RAW_TABLE *)" 74 /* A table with configurable parameters, to be loaded from the 75 /* global Postfix configuration file. Tables are loaded in the 76 /* order as specified, and multiple instances of the same type 77 /* are allowed. Raw parameters are not subjected to $name 78 /* evaluation. 79 /* .IP "CA_MAIL_SERVER_NINT_TABLE(CONFIG_NINT_TABLE *)" 80 /* A table with configurable parameters, to be loaded from the 81 /* global Postfix configuration file. Tables are loaded in the 82 /* order as specified, and multiple instances of the same type 83 /* are allowed. 84 /* .IP "CA_MAIL_SERVER_NBOOL_TABLE(CONFIG_NBOOL_TABLE *)" 85 /* A table with configurable parameters, to be loaded from the 86 /* global Postfix configuration file. Tables are loaded in the 87 /* order as specified, and multiple instances of the same type 88 /* are allowed. 89 /* .IP "CA_MAIL_SERVER_PRE_INIT(void *(char *service_name, char **argv))" 90 /* A pointer to a function that is called once 91 /* by the skeleton after it has read the global configuration file 92 /* and after it has processed command-line arguments, but before 93 /* the skeleton has optionally relinquished the process privileges. 94 /* .sp 95 /* Only the last instance of this parameter type is remembered. 96 /* .IP "CA_MAIL_SERVER_POST_INIT(void *(char *service_name, char **argv))" 97 /* A pointer to a function that is called once 98 /* by the skeleton after it has optionally relinquished the process 99 /* privileges, but before servicing client connection requests. 100 /* .sp 101 /* Only the last instance of this parameter type is remembered. 102 /* .IP "CA_MAIL_SERVER_LOOP(int *(char *service_name, char **argv))" 103 /* A pointer to function that is executed from 104 /* within the event loop, whenever an I/O or timer event has happened, 105 /* or whenever nothing has happened for a specified amount of time. 106 /* The result value of the function specifies how long to wait until 107 /* the next event. Specify -1 to wait for "as long as it takes". 108 /* .sp 109 /* Only the last instance of this parameter type is remembered. 110 /* .IP "CA_MAIL_SERVER_EXIT(void *(char *service_name, char **argv))" 111 /* A pointer to function that is executed immediately before normal 112 /* process termination. 113 /* .sp 114 /* Only the last instance of this parameter type is remembered. 115 /* .IP "CA_MAIL_SERVER_PRE_ACCEPT(void *(char *service_name, char **argv))" 116 /* Function to be executed prior to accepting a new request. 117 /* .sp 118 /* Only the last instance of this parameter type is remembered. 119 /* .IP "CA_MAIL_SERVER_IN_FLOW_DELAY(none)" 120 /* Pause $in_flow_delay seconds when no "mail flow control token" 121 /* is available. A token is consumed for each connection request. 122 /* .IP CA_MAIL_SERVER_SOLITARY 123 /* This service must be configured with process limit of 1. 124 /* .IP CA_MAIL_SERVER_UNLIMITED 125 /* This service must be configured with process limit of 0. 126 /* .IP CA_MAIL_SERVER_PRIVILEGED 127 /* This service must be configured as privileged. 128 /* .IP "CA_MAIL_SERVER_WATCHDOG(int *)" 129 /* Override the default 1000s watchdog timeout. The value is 130 /* used after command-line and main.cf file processing. 131 /* .IP "CA_MAIL_SERVER_BOUNCE_INIT(const char *, const char **)" 132 /* Initialize the DSN filter for the bounce/defer service 133 /* clients with the specified map source and map names. 134 /* .PP 135 /* The var_use_limit variable limits the number of clients that 136 /* a server can service before it commits suicide. 137 /* This value is taken from the global \fBmain.cf\fR configuration 138 /* file. Setting \fBvar_use_limit\fR to zero disables the client limit. 139 /* 140 /* The var_idle_limit variable limits the time that a service 141 /* receives no client connection requests before it commits suicide. 142 /* This value is taken from the global \fBmain.cf\fR configuration 143 /* file. Setting \fBvar_use_limit\fR to zero disables the idle limit. 144 /* DIAGNOSTICS 145 /* Problems and transactions are logged to \fBsyslogd\fR(8). 146 /* BUGS 147 /* Works with FIFO-based services only. 148 /* SEE ALSO 149 /* master(8), master process 150 /* syslogd(8) system logging 151 /* LICENSE 152 /* .ad 153 /* .fi 154 /* The Secure Mailer license must be distributed with this software. 155 /* AUTHOR(S) 156 /* Wietse Venema 157 /* IBM T.J. Watson Research 158 /* P.O. Box 704 159 /* Yorktown Heights, NY 10598, USA 160 /*--*/ 161 162 /* System library. */ 163 164 #include <sys_defs.h> 165 #include <sys/socket.h> 166 #include <unistd.h> 167 #include <signal.h> 168 #include <syslog.h> 169 #include <stdlib.h> 170 #include <limits.h> 171 #include <string.h> 172 #include <errno.h> 173 #include <fcntl.h> 174 #include <stdarg.h> 175 #ifdef STRCASECMP_IN_STRINGS_H 176 #include <strings.h> 177 #endif 178 #include <time.h> 179 180 /* Utility library. */ 181 182 #include <msg.h> 183 #include <msg_syslog.h> 184 #include <msg_vstream.h> 185 #include <chroot_uid.h> 186 #include <vstring.h> 187 #include <vstream.h> 188 #include <msg_vstream.h> 189 #include <mymalloc.h> 190 #include <events.h> 191 #include <iostuff.h> 192 #include <stringops.h> 193 #include <sane_accept.h> 194 #include <myflock.h> 195 #include <safe_open.h> 196 #include <listen.h> 197 #include <watchdog.h> 198 #include <split_at.h> 199 200 /* Global library. */ 201 202 #include <mail_params.h> 203 #include <mail_task.h> 204 #include <debug_process.h> 205 #include <mail_conf.h> 206 #include <mail_dict.h> 207 #include <resolve_local.h> 208 #include <mail_flow.h> 209 #include <mail_version.h> 210 #include <bounce.h> 211 212 /* Process manager. */ 213 214 #include "master_proto.h" 215 216 /* Application-specific */ 217 218 #include "mail_server.h" 219 220 /* 221 * Global state. 222 */ 223 static int use_count; 224 225 static TRIGGER_SERVER_FN trigger_server_service; 226 static char *trigger_server_name; 227 static char **trigger_server_argv; 228 static void (*trigger_server_accept) (int, void *); 229 static void (*trigger_server_onexit) (char *, char **); 230 static void (*trigger_server_pre_accept) (char *, char **); 231 static VSTREAM *trigger_server_lock; 232 static int trigger_server_in_flow_delay; 233 static unsigned trigger_server_generation; 234 static int trigger_server_watchdog = 1000; 235 236 /* trigger_server_exit - normal termination */ 237 238 static NORETURN trigger_server_exit(void) 239 { 240 if (trigger_server_onexit) 241 trigger_server_onexit(trigger_server_name, trigger_server_argv); 242 exit(0); 243 } 244 245 /* trigger_server_abort - terminate after abnormal master exit */ 246 247 static void trigger_server_abort(int unused_event, void *unused_context) 248 { 249 if (msg_verbose) 250 msg_info("master disconnect -- exiting"); 251 trigger_server_exit(); 252 } 253 254 /* trigger_server_timeout - idle time exceeded */ 255 256 static void trigger_server_timeout(int unused_event, void *unused_context) 257 { 258 if (msg_verbose) 259 msg_info("idle timeout -- exiting"); 260 trigger_server_exit(); 261 } 262 263 /* trigger_server_wakeup - wake up application */ 264 265 static void trigger_server_wakeup(int fd) 266 { 267 char buf[TRIGGER_BUF_SIZE]; 268 ssize_t len; 269 270 /* 271 * Commit suicide when the master process disconnected from us. Don't 272 * drop the already accepted client request after "postfix reload"; that 273 * would be rude. 274 */ 275 if (master_notify(var_pid, trigger_server_generation, MASTER_STAT_TAKEN) < 0) 276 /* void */ ; 277 if (trigger_server_in_flow_delay && mail_flow_get(1) < 0) 278 doze(var_in_flow_delay * 1000000); 279 if ((len = read(fd, buf, sizeof(buf))) >= 0) 280 trigger_server_service(buf, len, trigger_server_name, 281 trigger_server_argv); 282 if (master_notify(var_pid, trigger_server_generation, MASTER_STAT_AVAIL) < 0) 283 trigger_server_abort(EVENT_NULL_TYPE, EVENT_NULL_CONTEXT); 284 if (var_idle_limit > 0) 285 event_request_timer(trigger_server_timeout, (void *) 0, var_idle_limit); 286 /* Avoid integer wrap-around in a persistent process. */ 287 if (use_count < INT_MAX) 288 use_count++; 289 } 290 291 /* trigger_server_accept_fifo - accept fifo client request */ 292 293 static void trigger_server_accept_fifo(int unused_event, void *context) 294 { 295 const char *myname = "trigger_server_accept_fifo"; 296 int listen_fd = CAST_ANY_PTR_TO_INT(context); 297 298 if (trigger_server_lock != 0 299 && myflock(vstream_fileno(trigger_server_lock), INTERNAL_LOCK, 300 MYFLOCK_OP_NONE) < 0) 301 msg_fatal("select unlock: %m"); 302 303 if (msg_verbose) 304 msg_info("%s: trigger arrived", myname); 305 306 /* 307 * Read whatever the other side wrote into the FIFO. The FIFO read end is 308 * non-blocking so we won't get stuck when multiple processes wake up. 309 */ 310 if (trigger_server_pre_accept) 311 trigger_server_pre_accept(trigger_server_name, trigger_server_argv); 312 trigger_server_wakeup(listen_fd); 313 } 314 315 /* trigger_server_accept_local - accept socket client request */ 316 317 static void trigger_server_accept_local(int unused_event, void *context) 318 { 319 const char *myname = "trigger_server_accept_local"; 320 int listen_fd = CAST_ANY_PTR_TO_INT(context); 321 int time_left = 0; 322 int fd; 323 324 if (msg_verbose) 325 msg_info("%s: trigger arrived", myname); 326 327 /* 328 * Read a message from a socket. Be prepared for accept() to fail because 329 * some other process already got the connection. The socket is 330 * non-blocking so we won't get stuck when multiple processes wake up. 331 * Don't get stuck when the client connects but sends no data. Restart 332 * the idle timer if this was a false alarm. 333 */ 334 if (var_idle_limit > 0) 335 time_left = event_cancel_timer(trigger_server_timeout, (void *) 0); 336 337 if (trigger_server_pre_accept) 338 trigger_server_pre_accept(trigger_server_name, trigger_server_argv); 339 fd = LOCAL_ACCEPT(listen_fd); 340 if (trigger_server_lock != 0 341 && myflock(vstream_fileno(trigger_server_lock), INTERNAL_LOCK, 342 MYFLOCK_OP_NONE) < 0) 343 msg_fatal("select unlock: %m"); 344 if (fd < 0) { 345 if (errno != EAGAIN) 346 msg_error("accept connection: %m"); 347 if (time_left >= 0) 348 event_request_timer(trigger_server_timeout, (void *) 0, time_left); 349 return; 350 } 351 close_on_exec(fd, CLOSE_ON_EXEC); 352 if (read_wait(fd, 10) == 0) 353 trigger_server_wakeup(fd); 354 else if (time_left >= 0) 355 event_request_timer(trigger_server_timeout, (void *) 0, time_left); 356 close(fd); 357 } 358 359 #ifdef MASTER_XPORT_NAME_PASS 360 361 /* trigger_server_accept_pass - accept descriptor */ 362 363 static void trigger_server_accept_pass(int unused_event, void *context) 364 { 365 const char *myname = "trigger_server_accept_pass"; 366 int listen_fd = CAST_ANY_PTR_TO_INT(context); 367 int time_left = 0; 368 int fd; 369 370 if (msg_verbose) 371 msg_info("%s: trigger arrived", myname); 372 373 /* 374 * Read a message from a socket. Be prepared for accept() to fail because 375 * some other process already got the connection. The socket is 376 * non-blocking so we won't get stuck when multiple processes wake up. 377 * Don't get stuck when the client connects but sends no data. Restart 378 * the idle timer if this was a false alarm. 379 */ 380 if (var_idle_limit > 0) 381 time_left = event_cancel_timer(trigger_server_timeout, (void *) 0); 382 383 if (trigger_server_pre_accept) 384 trigger_server_pre_accept(trigger_server_name, trigger_server_argv); 385 fd = pass_accept(listen_fd); 386 if (trigger_server_lock != 0 387 && myflock(vstream_fileno(trigger_server_lock), INTERNAL_LOCK, 388 MYFLOCK_OP_NONE) < 0) 389 msg_fatal("select unlock: %m"); 390 if (fd < 0) { 391 if (errno != EAGAIN) 392 msg_error("accept connection: %m"); 393 if (time_left >= 0) 394 event_request_timer(trigger_server_timeout, (void *) 0, time_left); 395 return; 396 } 397 close_on_exec(fd, CLOSE_ON_EXEC); 398 if (read_wait(fd, 10) == 0) 399 trigger_server_wakeup(fd); 400 else if (time_left >= 0) 401 event_request_timer(trigger_server_timeout, (void *) 0, time_left); 402 close(fd); 403 } 404 405 #endif 406 407 /* trigger_server_main - the real main program */ 408 409 NORETURN trigger_server_main(int argc, char **argv, TRIGGER_SERVER_FN service,...) 410 { 411 const char *myname = "trigger_server_main"; 412 char *root_dir = 0; 413 char *user_name = 0; 414 int debug_me = 0; 415 int daemon_mode = 1; 416 char *service_name = basename(argv[0]); 417 VSTREAM *stream = 0; 418 int delay; 419 int c; 420 int socket_count = 1; 421 int fd; 422 va_list ap; 423 MAIL_SERVER_INIT_FN pre_init = 0; 424 MAIL_SERVER_INIT_FN post_init = 0; 425 MAIL_SERVER_LOOP_FN loop = 0; 426 int key; 427 char buf[TRIGGER_BUF_SIZE]; 428 ssize_t len; 429 char *transport = 0; 430 char *lock_path; 431 VSTRING *why; 432 int alone = 0; 433 int zerolimit = 0; 434 WATCHDOG *watchdog; 435 char *oname_val; 436 char *oname; 437 char *oval; 438 const char *err; 439 char *generation; 440 int msg_vstream_needed = 0; 441 int redo_syslog_init = 0; 442 const char *dsn_filter_title; 443 const char **dsn_filter_maps; 444 445 /* 446 * Process environment options as early as we can. 447 */ 448 if (getenv(CONF_ENV_VERB)) 449 msg_verbose = 1; 450 if (getenv(CONF_ENV_DEBUG)) 451 debug_me = 1; 452 453 /* 454 * Don't die when a process goes away unexpectedly. 455 */ 456 signal(SIGPIPE, SIG_IGN); 457 458 /* 459 * Don't die for frivolous reasons. 460 */ 461 #ifdef SIGXFSZ 462 signal(SIGXFSZ, SIG_IGN); 463 #endif 464 465 /* 466 * May need this every now and then. 467 */ 468 var_procname = mystrdup(basename(argv[0])); 469 set_mail_conf_str(VAR_PROCNAME, var_procname); 470 471 /* 472 * Initialize logging and exit handler. Do the syslog first, so that its 473 * initialization completes before we enter the optional chroot jail. 474 */ 475 msg_syslog_init(mail_task(var_procname), LOG_PID, LOG_FACILITY); 476 if (msg_verbose) 477 msg_info("daemon started"); 478 479 /* 480 * Check the Postfix library version as soon as we enable logging. 481 */ 482 MAIL_VERSION_CHECK; 483 484 /* 485 * Initialize from the configuration file. Allow command-line options to 486 * override compiled-in defaults or configured parameter values. 487 */ 488 mail_conf_suck(); 489 490 /* 491 * After database open error, continue execution with reduced 492 * functionality. 493 */ 494 dict_allow_surrogate = 1; 495 496 /* 497 * Pick up policy settings from master process. Shut up error messages to 498 * stderr, because no-one is going to see them. 499 */ 500 opterr = 0; 501 while ((c = GETOPT(argc, argv, "cdDi:lm:n:o:s:St:uvVz")) > 0) { 502 switch (c) { 503 case 'c': 504 root_dir = "setme"; 505 break; 506 case 'd': 507 daemon_mode = 0; 508 break; 509 case 'D': 510 debug_me = 1; 511 break; 512 case 'i': 513 mail_conf_update(VAR_MAX_IDLE, optarg); 514 break; 515 case 'l': 516 alone = 1; 517 break; 518 case 'm': 519 mail_conf_update(VAR_MAX_USE, optarg); 520 break; 521 case 'n': 522 service_name = optarg; 523 break; 524 case 'o': 525 oname_val = mystrdup(optarg); 526 if ((err = split_nameval(oname_val, &oname, &oval)) != 0) 527 msg_fatal("invalid \"-o %s\" option value: %s", optarg, err); 528 mail_conf_update(oname, oval); 529 if (strcmp(oname, VAR_SYSLOG_NAME) == 0) 530 redo_syslog_init = 1; 531 myfree(oname_val); 532 break; 533 case 's': 534 if ((socket_count = atoi(optarg)) <= 0) 535 msg_fatal("invalid socket_count: %s", optarg); 536 break; 537 case 'S': 538 stream = VSTREAM_IN; 539 break; 540 case 't': 541 transport = optarg; 542 break; 543 case 'u': 544 user_name = "setme"; 545 break; 546 case 'v': 547 msg_verbose++; 548 break; 549 case 'V': 550 if (++msg_vstream_needed == 1) 551 msg_vstream_init(mail_task(var_procname), VSTREAM_ERR); 552 break; 553 case 'z': 554 zerolimit = 1; 555 break; 556 default: 557 msg_fatal("invalid option: %c", c); 558 break; 559 } 560 } 561 562 /* 563 * Initialize generic parameters. 564 */ 565 mail_params_init(); 566 if (redo_syslog_init) 567 msg_syslog_init(mail_task(var_procname), LOG_PID, LOG_FACILITY); 568 569 /* 570 * Register higher-level dictionaries and initialize the support for 571 * dynamically-loaded dictionarles. 572 */ 573 mail_dict_init(); 574 575 /* 576 * If not connected to stdin, stdin must not be a terminal. 577 */ 578 if (daemon_mode && stream == 0 && isatty(STDIN_FILENO)) { 579 msg_vstream_init(var_procname, VSTREAM_ERR); 580 msg_fatal("do not run this command by hand"); 581 } 582 583 /* 584 * Application-specific initialization. 585 */ 586 va_start(ap, service); 587 while ((key = va_arg(ap, int)) != 0) { 588 switch (key) { 589 case MAIL_SERVER_INT_TABLE: 590 get_mail_conf_int_table(va_arg(ap, CONFIG_INT_TABLE *)); 591 break; 592 case MAIL_SERVER_LONG_TABLE: 593 get_mail_conf_long_table(va_arg(ap, CONFIG_LONG_TABLE *)); 594 break; 595 case MAIL_SERVER_STR_TABLE: 596 get_mail_conf_str_table(va_arg(ap, CONFIG_STR_TABLE *)); 597 break; 598 case MAIL_SERVER_BOOL_TABLE: 599 get_mail_conf_bool_table(va_arg(ap, CONFIG_BOOL_TABLE *)); 600 break; 601 case MAIL_SERVER_TIME_TABLE: 602 get_mail_conf_time_table(va_arg(ap, CONFIG_TIME_TABLE *)); 603 break; 604 case MAIL_SERVER_RAW_TABLE: 605 get_mail_conf_raw_table(va_arg(ap, CONFIG_RAW_TABLE *)); 606 break; 607 case MAIL_SERVER_NINT_TABLE: 608 get_mail_conf_nint_table(va_arg(ap, CONFIG_NINT_TABLE *)); 609 break; 610 case MAIL_SERVER_NBOOL_TABLE: 611 get_mail_conf_nbool_table(va_arg(ap, CONFIG_NBOOL_TABLE *)); 612 break; 613 case MAIL_SERVER_PRE_INIT: 614 pre_init = va_arg(ap, MAIL_SERVER_INIT_FN); 615 break; 616 case MAIL_SERVER_POST_INIT: 617 post_init = va_arg(ap, MAIL_SERVER_INIT_FN); 618 break; 619 case MAIL_SERVER_LOOP: 620 loop = va_arg(ap, MAIL_SERVER_LOOP_FN); 621 break; 622 case MAIL_SERVER_EXIT: 623 trigger_server_onexit = va_arg(ap, MAIL_SERVER_EXIT_FN); 624 break; 625 case MAIL_SERVER_PRE_ACCEPT: 626 trigger_server_pre_accept = va_arg(ap, MAIL_SERVER_ACCEPT_FN); 627 break; 628 case MAIL_SERVER_IN_FLOW_DELAY: 629 trigger_server_in_flow_delay = 1; 630 break; 631 case MAIL_SERVER_SOLITARY: 632 if (stream == 0 && !alone) 633 msg_fatal("service %s requires a process limit of 1", 634 service_name); 635 break; 636 case MAIL_SERVER_UNLIMITED: 637 if (stream == 0 && !zerolimit) 638 msg_fatal("service %s requires a process limit of 0", 639 service_name); 640 break; 641 case MAIL_SERVER_PRIVILEGED: 642 if (user_name) 643 msg_fatal("service %s requires privileged operation", 644 service_name); 645 break; 646 case MAIL_SERVER_WATCHDOG: 647 trigger_server_watchdog = *va_arg(ap, int *); 648 break; 649 case MAIL_SERVER_BOUNCE_INIT: 650 dsn_filter_title = va_arg(ap, const char *); 651 dsn_filter_maps = va_arg(ap, const char **); 652 bounce_client_init(dsn_filter_title, *dsn_filter_maps); 653 break; 654 default: 655 msg_panic("%s: unknown argument type: %d", myname, key); 656 } 657 } 658 va_end(ap); 659 660 if (root_dir) 661 root_dir = var_queue_dir; 662 if (user_name) 663 user_name = var_mail_owner; 664 665 /* 666 * Can options be required? 667 * 668 * XXX Initially this code was implemented with UNIX-domain sockets, but 669 * Solaris <= 2.5 UNIX-domain sockets misbehave hopelessly when the 670 * client disconnects before the server has accepted the connection. 671 * Symptom: the server accept() fails with EPIPE or EPROTO, but the 672 * socket stays readable, so that the program goes into a wasteful loop. 673 * 674 * The initial fix was to use FIFOs, but those turn out to have their own 675 * problems, witness the workarounds in the fifo_listen() routine. 676 * Therefore we support both FIFOs and UNIX-domain sockets, so that the 677 * user can choose whatever works best. 678 * 679 * Well, I give up. Solaris UNIX-domain sockets still don't work properly, 680 * so it will have to limp along with a streams-specific alternative. 681 */ 682 if (stream == 0) { 683 if (transport == 0) 684 msg_fatal("no transport type specified"); 685 if (strcasecmp(transport, MASTER_XPORT_NAME_UNIX) == 0) 686 trigger_server_accept = trigger_server_accept_local; 687 else if (strcasecmp(transport, MASTER_XPORT_NAME_FIFO) == 0) 688 trigger_server_accept = trigger_server_accept_fifo; 689 #ifdef MASTER_XPORT_NAME_PASS 690 else if (strcasecmp(transport, MASTER_XPORT_NAME_PASS) == 0) 691 trigger_server_accept = trigger_server_accept_pass; 692 #endif 693 else 694 msg_fatal("unsupported transport type: %s", transport); 695 } 696 697 /* 698 * Retrieve process generation from environment. 699 */ 700 if ((generation = getenv(MASTER_GEN_NAME)) != 0) { 701 if (!alldig(generation)) 702 msg_fatal("bad generation: %s", generation); 703 OCTAL_TO_UNSIGNED(trigger_server_generation, generation); 704 if (msg_verbose) 705 msg_info("process generation: %s (%o)", 706 generation, trigger_server_generation); 707 } 708 709 /* 710 * Optionally start the debugger on ourself. 711 */ 712 if (debug_me) 713 debug_process(); 714 715 /* 716 * Traditionally, BSD select() can't handle multiple processes selecting 717 * on the same socket, and wakes up every process in select(). See TCP/IP 718 * Illustrated volume 2 page 532. We avoid select() collisions with an 719 * external lock file. 720 */ 721 if (stream == 0 && !alone) { 722 lock_path = concatenate(DEF_PID_DIR, "/", transport, 723 ".", service_name, (char *) 0); 724 why = vstring_alloc(1); 725 if ((trigger_server_lock = safe_open(lock_path, O_CREAT | O_RDWR, 0600, 726 (struct stat *) 0, -1, -1, why)) == 0) 727 msg_fatal("open lock file %s: %s", lock_path, vstring_str(why)); 728 close_on_exec(vstream_fileno(trigger_server_lock), CLOSE_ON_EXEC); 729 myfree(lock_path); 730 vstring_free(why); 731 } 732 733 /* 734 * Set up call-back info. 735 */ 736 trigger_server_service = service; 737 trigger_server_name = service_name; 738 trigger_server_argv = argv + optind; 739 740 /* 741 * Run pre-jail initialization. 742 */ 743 if (chdir(var_queue_dir) < 0) 744 msg_fatal("chdir(\"%s\"): %m", var_queue_dir); 745 if (pre_init) 746 pre_init(trigger_server_name, trigger_server_argv); 747 748 /* 749 * Optionally, restrict the damage that this process can do. 750 */ 751 resolve_local_init(); 752 tzset(); 753 chroot_uid(root_dir, user_name); 754 755 /* 756 * Run post-jail initialization. 757 */ 758 if (post_init) 759 post_init(trigger_server_name, trigger_server_argv); 760 761 /* 762 * Are we running as a one-shot server with the client connection on 763 * standard input? 764 */ 765 if (stream != 0) { 766 if ((len = read(vstream_fileno(stream), buf, sizeof(buf))) <= 0) 767 msg_fatal("read: %m"); 768 service(buf, len, trigger_server_name, trigger_server_argv); 769 vstream_fflush(stream); 770 trigger_server_exit(); 771 } 772 773 /* 774 * Running as a semi-resident server. Service connection requests. 775 * Terminate when we have serviced a sufficient number of clients, when 776 * no-one has been talking to us for a configurable amount of time, or 777 * when the master process terminated abnormally. 778 */ 779 if (var_idle_limit > 0) 780 event_request_timer(trigger_server_timeout, (void *) 0, var_idle_limit); 781 for (fd = MASTER_LISTEN_FD; fd < MASTER_LISTEN_FD + socket_count; fd++) { 782 event_enable_read(fd, trigger_server_accept, CAST_INT_TO_VOID_PTR(fd)); 783 close_on_exec(fd, CLOSE_ON_EXEC); 784 } 785 event_enable_read(MASTER_STATUS_FD, trigger_server_abort, (void *) 0); 786 close_on_exec(MASTER_STATUS_FD, CLOSE_ON_EXEC); 787 close_on_exec(MASTER_FLOW_READ, CLOSE_ON_EXEC); 788 close_on_exec(MASTER_FLOW_WRITE, CLOSE_ON_EXEC); 789 watchdog = watchdog_create(trigger_server_watchdog, 790 (WATCHDOG_FN) 0, (void *) 0); 791 792 /* 793 * The event loop, at last. 794 */ 795 while (var_use_limit == 0 || use_count < var_use_limit) { 796 if (trigger_server_lock != 0) { 797 watchdog_stop(watchdog); 798 if (myflock(vstream_fileno(trigger_server_lock), INTERNAL_LOCK, 799 MYFLOCK_OP_EXCLUSIVE) < 0) 800 msg_fatal("select lock: %m"); 801 } 802 watchdog_start(watchdog); 803 delay = loop ? loop(trigger_server_name, trigger_server_argv) : -1; 804 event_loop(delay); 805 } 806 trigger_server_exit(); 807 } 808