1 /* This file is part of the Project Athena Zephyr Notification System.
2 * It contains the main loop of the Zephyr server
4 * Created by: John T. Kohl
6 * $Source: /afs/dev.mit.edu/source/repository/athena/lib/zephyr/server/main.c,v $
9 * Copyright (c) 1987,1988,1991 by the Massachusetts Institute of Technology.
10 * For copying and distribution information, see the file
14 #include <zephyr/mit-copyright.h>
16 #include <sys/socket.h>
17 #include <sys/resource.h>
21 static const char rcsid_main_c[] =
22 "$Id: main.c,v 1.69 2001/02/27 04:50:08 zacheiss Exp $";
27 * Server loop for Zephyr.
31 The Zephyr server maintains several linked lists of information.
33 There is an array of servers (otherservers) initialized and maintained
36 Each server descriptor contains a pointer to a linked list of hosts
37 which are ``owned'' by that server. The first server is the ``limbo''
38 server which owns any host which was formerly owned by a dead server.
40 Each of these host list entries has an IP address and a pointer to a
41 linked list of clients on that host.
43 Each client has a sockaddr_in, a list of subscriptions, and possibly
46 In addition, the class manager has copies of the pointers to the
47 clients which are registered with a particular class, the
48 not-yet-acknowledged list has copies of pointers to some clients,
49 and the hostm manager may have copies of pointers to some clients
50 (if the client has not acknowledged a packet after a given timeout).
53 #define EVER (;;) /* don't stop looping */
55 static int do_net_setup __P((void));
56 static int initialize __P((void));
57 static void usage __P((void));
58 static void do_reset __P((void));
59 static RETSIGTYPE bye __P((int));
60 static RETSIGTYPE dbug_on __P((int));
61 static RETSIGTYPE dbug_off __P((int));
62 static RETSIGTYPE sig_dump_db __P((int));
63 static RETSIGTYPE sig_dump_strings __P((int));
64 static RETSIGTYPE reset __P((int));
65 static RETSIGTYPE reap __P((int));
66 static void read_from_dump __P((char *dumpfile));
67 static void dump_db __P((void));
68 static void dump_strings __P((void));
71 static void detach __P((void));
74 static short doreset = 0; /* if it becomes 1, perform
77 int nfds; /* max file descriptor for select() */
78 int srv_socket; /* dgram socket for clients
80 int bdump_socket = -1; /* brain dump socket fd
81 (closed most of the time) */
82 fd_set interesting; /* the file descrips we are listening
84 struct sockaddr_in srv_addr; /* address of the socket */
86 Unacked *nacklist = NULL; /* list of packets waiting for ack's */
88 unsigned short hm_port; /* host manager receiver port */
89 unsigned short hm_srv_port; /* host manager server sending port */
91 char *programname; /* set to the basename of argv[0] */
92 char myname[MAXHOSTNAMELEN]; /* my host name */
96 char keytab_file[128];
97 static char tkt5_file[256];
100 char srvtab_file[128];
101 char my_realm[REALM_SZ];
102 static char tkt_file[128];
109 int dump_malloc_stats = 0;
110 unsigned long m_size;
116 struct timeval t_local; /* store current time for other uses */
118 static int dump_db_flag = 0;
119 static int dump_strings_flag = 0;
121 u_long npackets; /* number of packets processed */
122 time_t uptime; /* when we started operations */
124 struct in_addr my_addr;
125 char *bdump_version = "1.2";
128 krb5_ccache Z_krb5_ccache;
132 C_Block __Zephyr_session;
140 int nfound; /* #fildes ready on select */
143 int init_from_dump = 0;
145 #ifdef _POSIX_VERSION
146 struct sigaction action;
148 int optchar; /* option processing */
152 sprintf(list_file, "%s/zephyr/%s", SYSCONFDIR, SERVER_LIST_FILE);
154 sprintf(srvtab_file, "%s/zephyr/%s", SYSCONFDIR, ZEPHYR_SRVTAB);
155 sprintf(tkt_file, "%s/zephyr/%s", SYSCONFDIR, ZEPHYR_TKFILE);
158 sprintf(keytab_file, "%s/zephyr/%s", SYSCONFDIR, ZEPHYR_KEYTAB);
159 sprintf(tkt5_file, "FILE:%s/zephyr/%s", SYSCONFDIR, ZEPHYR_TK5FILE);
161 sprintf(acl_dir, "%s/zephyr/%s", SYSCONFDIR, ZEPHYR_ACL_DIR);
162 sprintf(subs_file, "%s/zephyr/%s", SYSCONFDIR, DEFAULT_SUBS_FILE);
165 programname = strrchr(argv[0],'/');
166 programname = (programname) ? programname + 1 : argv[0];
168 /* process arguments */
169 while ((optchar = getopt(argc, argv, "dsnv:f:k:")) != EOF) {
184 strncpy(my_realm, optarg, REALM_SZ);
188 bdump_version = optarg;
202 /* if there is no readable srvtab and we are not standalone, there
203 is no possible way we can succeed, so we exit */
205 if (access(srvtab_file, R_OK)
210 fprintf(stderr, "NO ZEPHYR SRVTAB (%s) available; exiting\n",
214 /* Use local realm if not specified on command line. */
216 if (krb_get_lrealm(my_realm, 1) != KSUCCESS) {
217 fputs("Couldn't get local Kerberos realm; exiting.\n", stderr);
221 #endif /* HAVE_KRB4 */
229 OPENLOG(programname, LOG_PID, LOG_LOCAL6);
231 #if defined (DEBUG) && 0
233 syslog(LOG_DEBUG, "standalone operation");
237 syslog(LOG_DEBUG, "debugging on");
240 /* set up sockets & my_addr and myname,
241 find other servers and set up server table, initialize queues
242 for retransmits, initialize error tables,
243 set up restricted classes */
245 /* Initialize t_local for other uses */
246 gettimeofday(&t_local, NULL);
252 read_from_dump(dumpfile);
254 /* Seed random number set. */
255 srandom(getpid() ^ time(0));
257 /* chdir to somewhere where a core dump will survive */
258 if (chdir(TEMP_DIRECTORY) != 0)
259 syslog(LOG_ERR, "chdir failed (%m) (execution continuing)");
261 FD_ZERO(&interesting);
262 FD_SET(srv_socket, &interesting);
264 nfds = srv_socket + 1;
267 #ifdef _POSIX_VERSION
269 sigemptyset(&action.sa_mask);
271 action.sa_handler = bye;
272 sigaction(SIGINT, &action, NULL);
273 sigaction(SIGTERM, &action, NULL);
275 action.sa_handler = dbug_on;
276 sigaction(SIGUSR1, &action, NULL);
278 action.sa_handler = dbug_off;
279 sigaction(SIGUSR2, &action, NULL);
281 action.sa_handler = reap;
282 sigaction(SIGCHLD, &action, NULL);
284 action.sa_handler = sig_dump_db;
285 sigaction(SIGFPE, &action, NULL);
288 action.sa_handler = sig_dump_strings;
289 sigaction(SIGEMT, &action, NULL);
292 action.sa_handler = reset;
293 sigaction(SIGHUP, &action, NULL);
296 signal(SIGTERM, bye);
297 signal(SIGUSR1, dbug_on);
298 signal(SIGUSR2, dbug_off);
299 signal(SIGCHLD, reap);
300 signal(SIGFPE, sig_dump_db);
302 signal(SIGEMT, sig_dump_strings);
304 signal(SIGHUP, reset);
305 #endif /* _POSIX_VERSION */
307 syslog(LOG_NOTICE, "Ready for action");
309 /* Reinitialize t_local now that initialization is done. */
310 gettimeofday(&t_local, NULL);
313 timer_set_rel(SWEEP_INTERVAL, sweep_ticket_hash_table, NULL);
318 malloc_inuse(&m_size);
326 if (dump_strings_flag)
331 readable = interesting;
333 /* when there is input in the queue, we
334 artificially set up to pick up the input */
338 nfound = select(nfds, &readable, NULL, NULL, timer_timeout(&tv));
341 /* Initialize t_local for other uses */
342 gettimeofday(&t_local, (struct timezone *)0);
344 /* don't flame about EINTR, since a SIGUSR1 or SIGUSR2
345 can generate it by interrupting the select */
348 syslog(LOG_WARNING, "select error: %m");
350 if (dump_malloc_stats) {
351 unsigned long foo,histid2;
353 dump_malloc_stats = 0;
354 foo = malloc_inuse(&histid2);
355 printf("Total inuse: %d\n",foo);
356 malloc_list(2,m_size,histid2);
363 /* either we timed out or we were just
364 polling for input. Either way we want to continue
365 the loop, and process the next timeout */
368 if (bdump_socket >= 0 && FD_ISSET(bdump_socket,&readable))
370 else if (msgs_queued() || FD_ISSET(srv_socket, &readable))
373 syslog(LOG_ERR, "select weird?!?!");
378 /* Initialize net stuff.
379 Set up the server array.
380 Initialize the packet ack queues to be empty.
381 Initialize the error tables.
382 Restrict certain classes.
395 krb_set_tkt_string(tkt_file);
400 ZInitialize(); /* set up the library */
402 krb5_cc_resolve(Z_krb5_ctx, tkt5_file, &Z_krb5_ccache);
403 #ifdef HAVE_KRB5_CC_SET_DEFAULT_NAME
404 krb5_cc_set_default_name(Z_krb5_ctx, tkt5_file);
407 /* Hack to make krb5_cc_default do something reasonable */
408 char *env=(char *)malloc(strlen(tkt5_file)+12);
410 sprintf(env, "KRB5CCNAME=%s", tkt5_file);
416 /* Override what Zinitialize set for ZGetRealm() */
418 strcpy(__Zephyr_realm, my_realm);
420 init_zsrv_err_tbl(); /* set up err table */
422 ZSetFD(srv_socket); /* set up the socket as the input fildes */
424 /* set up default strings */
426 class_control = make_string(ZEPHYR_CTL_CLASS, 1);
427 class_admin = make_string(ZEPHYR_ADMIN_CLASS, 1);
428 class_hm = make_string(HM_CTL_CLASS, 1);
429 class_ulogin = make_string(LOGIN_CLASS, 1);
430 class_ulocate = make_string(LOCATE_CLASS, 1);
431 wildcard_instance = make_string(WILDCARD_INSTANCE, 1);
432 empty = make_string("", 0);
434 /* restrict certain classes */
440 * Set up the server and client sockets, and initialize my_addr and myname
448 char hostname[MAXHOSTNAMELEN+1];
451 if (gethostname(hostname, MAXHOSTNAMELEN + 1)) {
452 syslog(LOG_ERR, "no hostname: %m");
455 hp = gethostbyname(hostname);
457 syslog(LOG_ERR, "no gethostbyname repsonse");
458 strncpy(myname, hostname, MAXHOSTNAMELEN);
461 strncpy(myname, hp->h_name, MAXHOSTNAMELEN);
462 memcpy(&my_addr, hp->h_addr, sizeof(hp->h_addr));
464 setservent(1); /* keep file/connection open */
466 memset(&srv_addr, 0, sizeof(srv_addr));
467 srv_addr.sin_family = AF_INET;
468 sp = getservbyname(SERVER_SVCNAME, "udp");
469 srv_addr.sin_port = (sp) ? sp->s_port : SERVER_SVC_FALLBACK;
471 sp = getservbyname(HM_SVCNAME, "udp");
472 hm_port = (sp) ? sp->s_port : HM_SVC_FALLBACK;
474 sp = getservbyname(HM_SRV_SVCNAME, "udp");
475 hm_srv_port = (sp) ? sp->s_port : HM_SRV_SVC_FALLBACK;
477 srv_socket = socket(AF_INET, SOCK_DGRAM, 0);
478 if (srv_socket < 0) {
479 syslog(LOG_ERR, "client_sock failed: %m");
485 /* Prevent Linux from giving us socket errors we don't care about. */
486 setsockopt(srv_socket, SOL_SOCKET, SO_BSDCOMPAT, &on, sizeof(on));
489 if (bind(srv_socket, (struct sockaddr *) &srv_addr,
490 sizeof(srv_addr)) < 0) {
491 syslog(LOG_ERR, "client bind failed: %m");
495 /* set not-blocking */
496 #ifdef _POSIX_VERSION
497 flags = fcntl(srv_socket, F_GETFL);
499 fcntl(srv_socket, F_SETFL, flags);
502 ioctl(srv_socket, FIONBIO, &flags);
510 * print out a usage message.
517 fprintf(stderr, "Usage: %s [-d] [-s] [-n] [-k realm] [-f dumpfile]\n",
520 fprintf(stderr, "Usage: %s [-d] [-n] [-k realm] [-f dumpfile]\n",
529 fd_set readable, initial;
535 FD_SET(srv_socket, &initial);
537 tv.tv_sec = tv.tv_usec = 0;
538 return (select(srv_socket + 1, &readable, NULL, NULL, &tv) > 0);
545 server_shutdown(); /* tell other servers */
547 realm_shutdown(); /* tell other realms */
549 hostm_shutdown(); /* tell our hosts */
554 syslog(LOG_NOTICE, "goodbye (sig %d)", sig);
562 syslog(LOG_DEBUG, "debugging turned on");
564 dump_malloc_stats = 1;
573 syslog(LOG_DEBUG, "debugging turned off");
575 malloc_inuse(&m_size);
580 int fork_for_dump = 0;
583 sig_dump_strings(sig)
586 dump_strings_flag = 1;
589 static void dump_strings()
596 sprintf(filename, "%szephyr.strings", TEMP_DIRECTORY);
597 fp = fopen (filename, "w");
599 syslog(LOG_ERR, "can't open strings dump file: %m");
601 dump_strings_flag = 0;
604 syslog(LOG_INFO, "dumping strings to disk");
605 print_string_table(fp);
606 if (fclose(fp) == EOF)
607 syslog(LOG_ERR, "error writing strings dump file");
609 syslog(LOG_INFO, "dump done");
611 dump_strings_flag = 0;
622 static void dump_db()
624 /* dump the in-core database to human-readable form on disk */
630 pid = (fork_for_dump) ? fork() : -1;
635 sprintf(filename, "%szephyr.db", TEMP_DIRECTORY);
636 fp = fopen(filename, "w");
638 syslog(LOG_ERR, "can't open dump database");
643 syslog(LOG_INFO, "dumping to disk");
644 server_dump_servers(fp);
646 client_dump_clients(fp);
647 triplet_dump_subs(fp);
648 realm_dump_realms(fp);
649 syslog(LOG_INFO, "dump done");
650 if (fclose(fp) == EOF)
651 syslog(LOG_ERR, "can't close dump db");
663 zdbug((LOG_DEBUG,"reset()"));
675 #ifdef _POSIX_VERSION
681 zdbug((LOG_DEBUG,"reap()"));
683 #ifdef _POSIX_VERSION
684 while ((pid = waitpid(-1, &waitb, WNOHANG)) == 0)
685 { i++; if (i > 10) break; }
687 while ((pid = wait3 (&waitb, WNOHANG, (struct rusage*) 0)) == 0)
688 { i++; if (i > 10) break; }
694 if (WIFSIGNALED(waitb) == 0) {
695 if (WIFEXITED(waitb) != 0) {
696 rlm = realm_get_realm_by_pid(pid);
703 rlm = realm_get_realm_by_pid(pid);
715 #ifdef _POSIX_VERSION
716 sigset_t mask, omask;
721 zdbug((LOG_DEBUG,"do_reset()"));
723 #ifdef _POSIX_VERSION
725 sigaddset(&mask, SIGHUP);
726 sigprocmask(SIG_BLOCK, &mask, &omask);
728 omask = sigblock(sigmask(SIGHUP));
731 /* reset various things in the server's state */
735 syslog(LOG_INFO, "restart completed");
738 #ifdef _POSIX_VERSION
739 sigprocmask(SIG_SETMASK, &omask, (sigset_t *)0);
747 * detach from the terminal
753 /* detach from terminal and fork. */
757 #ifdef _POSIX_VERSION
758 size = sysconf(_SC_OPEN_MAX);
760 size = getdtablesize();
762 /* profiling seems to get confused by fork() */
770 for (i = 0; i < size; i++)
773 i = open("/dev/tty", O_RDWR, 666);
774 #ifdef TIOCNOTTY /* Only necessary on old systems. */
775 ioctl(i, TIOCNOTTY, NULL);
778 #ifdef _POSIX_VERSION
782 #endif /* not DEBUG */
785 read_from_dump(dumpfile)
788 /* Not yet implemented. */