xref: /freebsd/crypto/heimdal/lib/kadm5/ipropd_slave.c (revision 8833b15f6382203d094cd6eb69068709b467079d)
1 /*
2  * Copyright (c) 1997 - 2008 Kungliga Tekniska Högskolan
3  * (Royal Institute of Technology, Stockholm, Sweden).
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  *
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * 3. Neither the name of the Institute nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include "iprop.h"
35 
36 RCSID("$Id$");
37 
38 static const char *config_name = "ipropd-slave";
39 
40 static krb5_log_facility *log_facility;
41 static char five_min[] = "5 min";
42 static char *server_time_lost = five_min;
43 static int time_before_lost;
44 const char *slave_str = NULL;
45 
46 static int
47 connect_to_master (krb5_context context, const char *master,
48 		   const char *port_str)
49 {
50     char port[NI_MAXSERV];
51     struct addrinfo *ai, *a;
52     struct addrinfo hints;
53     int error;
54     int s = -1;
55 
56     memset (&hints, 0, sizeof(hints));
57     hints.ai_socktype = SOCK_STREAM;
58 
59     if (port_str == NULL) {
60 	snprintf(port, sizeof(port), "%u", IPROP_PORT);
61 	port_str = port;
62     }
63 
64     error = getaddrinfo (master, port_str, &hints, &ai);
65     if (error) {
66 	krb5_warnx(context, "Failed to get address of to %s: %s",
67 		   master, gai_strerror(error));
68 	return -1;
69     }
70 
71     for (a = ai; a != NULL; a = a->ai_next) {
72 	char node[NI_MAXHOST];
73 	error = getnameinfo(a->ai_addr, a->ai_addrlen,
74 			    node, sizeof(node), NULL, 0, NI_NUMERICHOST);
75 	if (error)
76 	    strlcpy(node, "[unknown-addr]", sizeof(node));
77 
78 	s = socket (a->ai_family, a->ai_socktype, a->ai_protocol);
79 	if (s < 0)
80 	    continue;
81 	if (connect (s, a->ai_addr, a->ai_addrlen) < 0) {
82 	    krb5_warn(context, errno, "connection failed to %s[%s]",
83 		      master, node);
84 	    close (s);
85 	    continue;
86 	}
87 	krb5_warnx(context, "connection successful "
88 		   "to master: %s[%s]", master, node);
89 	break;
90     }
91     freeaddrinfo (ai);
92 
93     if (a == NULL)
94 	return -1;
95 
96     return s;
97 }
98 
99 static void
100 get_creds(krb5_context context, const char *keytab_str,
101 	  krb5_ccache *cache, const char *serverhost)
102 {
103     krb5_keytab keytab;
104     krb5_principal client;
105     krb5_error_code ret;
106     krb5_get_init_creds_opt *init_opts;
107     krb5_creds creds;
108     char *server;
109     char keytab_buf[256];
110 
111     if (keytab_str == NULL) {
112 	ret = krb5_kt_default_name (context, keytab_buf, sizeof(keytab_buf));
113 	if (ret)
114 	    krb5_err (context, 1, ret, "krb5_kt_default_name");
115 	keytab_str = keytab_buf;
116     }
117 
118     ret = krb5_kt_resolve(context, keytab_str, &keytab);
119     if(ret)
120 	krb5_err(context, 1, ret, "%s", keytab_str);
121 
122 
123     ret = krb5_sname_to_principal (context, slave_str, IPROP_NAME,
124 				   KRB5_NT_SRV_HST, &client);
125     if (ret) krb5_err(context, 1, ret, "krb5_sname_to_principal");
126 
127     ret = krb5_get_init_creds_opt_alloc(context, &init_opts);
128     if (ret) krb5_err(context, 1, ret, "krb5_get_init_creds_opt_alloc");
129 
130     asprintf (&server, "%s/%s", IPROP_NAME, serverhost);
131     if (server == NULL)
132 	krb5_errx (context, 1, "malloc: no memory");
133 
134     ret = krb5_get_init_creds_keytab(context, &creds, client, keytab,
135 				     0, server, init_opts);
136     free (server);
137     krb5_get_init_creds_opt_free(context, init_opts);
138     if(ret) krb5_err(context, 1, ret, "krb5_get_init_creds");
139 
140     ret = krb5_kt_close(context, keytab);
141     if(ret) krb5_err(context, 1, ret, "krb5_kt_close");
142 
143     ret = krb5_cc_new_unique(context, krb5_cc_type_memory, NULL, cache);
144     if(ret) krb5_err(context, 1, ret, "krb5_cc_new_unique");
145 
146     ret = krb5_cc_initialize(context, *cache, client);
147     if(ret) krb5_err(context, 1, ret, "krb5_cc_initialize");
148 
149     ret = krb5_cc_store_cred(context, *cache, &creds);
150     if(ret) krb5_err(context, 1, ret, "krb5_cc_store_cred");
151 
152     krb5_free_cred_contents(context, &creds);
153     krb5_free_principal(context, client);
154 }
155 
156 static krb5_error_code
157 ihave (krb5_context context, krb5_auth_context auth_context,
158        int fd, uint32_t version)
159 {
160     int ret;
161     u_char buf[8];
162     krb5_storage *sp;
163     krb5_data data;
164 
165     sp = krb5_storage_from_mem (buf, 8);
166     krb5_store_int32 (sp, I_HAVE);
167     krb5_store_int32 (sp, version);
168     krb5_storage_free (sp);
169     data.length = 8;
170     data.data   = buf;
171 
172     ret = krb5_write_priv_message(context, auth_context, &fd, &data);
173     if (ret)
174 	krb5_warn (context, ret, "krb5_write_message");
175     return ret;
176 }
177 
178 static void
179 receive_loop (krb5_context context,
180 	      krb5_storage *sp,
181 	      kadm5_server_context *server_context)
182 {
183     int ret;
184     off_t left, right;
185     void *buf;
186     int32_t vers, vers2;
187     ssize_t sret;
188 
189     /*
190      * Seek to the current version of the local database.
191      */
192     do {
193 	int32_t len, timestamp, tmp;
194 	enum kadm_ops op;
195 
196 	if(krb5_ret_int32 (sp, &vers) != 0)
197 	    return;
198 	krb5_ret_int32 (sp, &timestamp);
199 	krb5_ret_int32 (sp, &tmp);
200 	op = tmp;
201 	krb5_ret_int32 (sp, &len);
202 	if ((uint32_t)vers <= server_context->log_context.version)
203 	    krb5_storage_seek(sp, len + 8, SEEK_CUR);
204     } while((uint32_t)vers <= server_context->log_context.version);
205 
206     /*
207      * Read up rest of the entires into the memory...
208      */
209     left  = krb5_storage_seek (sp, -16, SEEK_CUR);
210     right = krb5_storage_seek (sp, 0, SEEK_END);
211     buf = malloc (right - left);
212     if (buf == NULL && (right - left) != 0)
213 	krb5_errx (context, 1, "malloc: no memory");
214 
215     /*
216      * ...and then write them out to the on-disk log.
217      */
218     krb5_storage_seek (sp, left, SEEK_SET);
219     krb5_storage_read (sp, buf, right - left);
220     sret = write (server_context->log_context.log_fd, buf, right-left);
221     if (sret != right - left)
222 	krb5_err(context, 1, errno, "Failed to write log to disk");
223     ret = fsync (server_context->log_context.log_fd);
224     if (ret)
225 	krb5_err(context, 1, errno, "Failed to sync log to disk");
226     free (buf);
227 
228     /*
229      * Go back to the startpoint and start to commit the entires to
230      * the database.
231      */
232     krb5_storage_seek (sp, left, SEEK_SET);
233 
234     for(;;) {
235 	int32_t len, len2, timestamp, tmp;
236 	off_t cur, cur2;
237 	enum kadm_ops op;
238 
239 	if(krb5_ret_int32 (sp, &vers) != 0)
240 	    break;
241 	ret = krb5_ret_int32 (sp, &timestamp);
242 	if (ret) krb5_errx(context, 1, "entry %ld: too short", (long)vers);
243 	ret = krb5_ret_int32 (sp, &tmp);
244 	if (ret) krb5_errx(context, 1, "entry %ld: too short", (long)vers);
245 	op = tmp;
246 	ret = krb5_ret_int32 (sp, &len);
247 	if (ret) krb5_errx(context, 1, "entry %ld: too short", (long)vers);
248 	if (len < 0)
249 	    krb5_errx(context, 1, "log is corrupted, "
250 		      "negative length of entry version %ld: %ld",
251 		      (long)vers, (long)len);
252 	cur = krb5_storage_seek(sp, 0, SEEK_CUR);
253 
254 	krb5_warnx (context, "replaying entry %d", (int)vers);
255 
256 	ret = kadm5_log_replay (server_context,
257 				op, vers, len, sp);
258 	if (ret) {
259 	    const char *s = krb5_get_error_message(server_context->context, ret);
260 	    krb5_warnx (context,
261 			"kadm5_log_replay: %ld. Lost entry entry, "
262 			"Database out of sync ?: %s (%d)",
263 			(long)vers, s ? s : "unknown error", ret);
264 	    krb5_free_error_message(context, s);
265 	}
266 
267 	{
268 	    /*
269 	     * Make sure the krb5_log_replay does the right thing wrt
270 	     * reading out data from the sp.
271 	     */
272 	    cur2 = krb5_storage_seek(sp, 0, SEEK_CUR);
273 	    if (cur + len != cur2)
274 		krb5_errx(context, 1,
275 			  "kadm5_log_reply version: %ld didn't read the whole entry",
276 			  (long)vers);
277 	}
278 
279 	if (krb5_ret_int32 (sp, &len2) != 0)
280 	    krb5_errx(context, 1, "entry %ld: postamble too short", (long)vers);
281 	if(krb5_ret_int32 (sp, &vers2) != 0)
282 	    krb5_errx(context, 1, "entry %ld: postamble too short", (long)vers);
283 
284 	if (len != len2)
285 	    krb5_errx(context, 1, "entry %ld: len != len2", (long)vers);
286 	if (vers != vers2)
287 	    krb5_errx(context, 1, "entry %ld: vers != vers2", (long)vers);
288     }
289 
290     /*
291      * Update version
292      */
293 
294     server_context->log_context.version = vers;
295 }
296 
297 static void
298 receive (krb5_context context,
299 	 krb5_storage *sp,
300 	 kadm5_server_context *server_context)
301 {
302     int ret;
303 
304     ret = server_context->db->hdb_open(context,
305 				       server_context->db,
306 				       O_RDWR | O_CREAT, 0600);
307     if (ret)
308 	krb5_err (context, 1, ret, "db->open");
309 
310     receive_loop (context, sp, server_context);
311 
312     ret = server_context->db->hdb_close (context, server_context->db);
313     if (ret)
314 	krb5_err (context, 1, ret, "db->close");
315 }
316 
317 static void
318 send_im_here (krb5_context context, int fd,
319 	      krb5_auth_context auth_context)
320 {
321     krb5_storage *sp;
322     krb5_data data;
323     int ret;
324 
325     ret = krb5_data_alloc (&data, 4);
326     if (ret)
327 	krb5_err (context, 1, ret, "send_im_here");
328 
329     sp = krb5_storage_from_data (&data);
330     if (sp == NULL)
331 	krb5_errx (context, 1, "krb5_storage_from_data");
332     krb5_store_int32(sp, I_AM_HERE);
333     krb5_storage_free(sp);
334 
335     ret = krb5_write_priv_message(context, auth_context, &fd, &data);
336     krb5_data_free(&data);
337 
338     if (ret)
339 	krb5_err (context, 1, ret, "krb5_write_priv_message");
340 }
341 
342 static krb5_error_code
343 receive_everything (krb5_context context, int fd,
344 		    kadm5_server_context *server_context,
345 		    krb5_auth_context auth_context)
346 {
347     int ret;
348     krb5_data data;
349     int32_t vno = 0;
350     int32_t opcode;
351     krb5_storage *sp;
352 
353     char *dbname;
354     HDB *mydb;
355 
356     krb5_warnx(context, "receive complete database");
357 
358     asprintf(&dbname, "%s-NEW", server_context->db->hdb_name);
359     ret = hdb_create(context, &mydb, dbname);
360     if(ret)
361 	krb5_err(context,1, ret, "hdb_create");
362     free(dbname);
363 
364     ret = hdb_set_master_keyfile (context,
365 				  mydb, server_context->config.stash_file);
366     if(ret)
367 	krb5_err(context,1, ret, "hdb_set_master_keyfile");
368 
369     /* I really want to use O_EXCL here, but given that I can't easily clean
370        up on error, I won't */
371     ret = mydb->hdb_open(context, mydb, O_RDWR | O_CREAT | O_TRUNC, 0600);
372     if (ret)
373 	krb5_err (context, 1, ret, "db->open");
374 
375     sp = NULL;
376     do {
377 	ret = krb5_read_priv_message(context, auth_context, &fd, &data);
378 
379 	if (ret) {
380 	    krb5_warn (context, ret, "krb5_read_priv_message");
381 	    goto cleanup;
382 	}
383 
384 	sp = krb5_storage_from_data (&data);
385 	if (sp == NULL)
386 	    krb5_errx (context, 1, "krb5_storage_from_data");
387 	krb5_ret_int32 (sp, &opcode);
388 	if (opcode == ONE_PRINC) {
389 	    krb5_data fake_data;
390 	    hdb_entry_ex entry;
391 
392 	    krb5_storage_free(sp);
393 
394 	    fake_data.data   = (char *)data.data + 4;
395 	    fake_data.length = data.length - 4;
396 
397 	    memset(&entry, 0, sizeof(entry));
398 
399 	    ret = hdb_value2entry (context, &fake_data, &entry.entry);
400 	    if (ret)
401 		krb5_err (context, 1, ret, "hdb_value2entry");
402 	    ret = mydb->hdb_store(server_context->context,
403 				  mydb,
404 				  0, &entry);
405 	    if (ret)
406 		krb5_err (context, 1, ret, "hdb_store");
407 
408 	    hdb_free_entry (context, &entry);
409 	    krb5_data_free (&data);
410 	} else if (opcode == NOW_YOU_HAVE)
411 	    ;
412 	else
413 	    krb5_errx (context, 1, "strange opcode %d", opcode);
414     } while (opcode == ONE_PRINC);
415 
416     if (opcode != NOW_YOU_HAVE)
417 	krb5_errx (context, 1, "receive_everything: strange %d", opcode);
418 
419     krb5_ret_int32 (sp, &vno);
420     krb5_storage_free(sp);
421 
422     ret = kadm5_log_reinit (server_context);
423     if (ret)
424 	krb5_err(context, 1, ret, "kadm5_log_reinit");
425 
426     ret = kadm5_log_set_version (server_context, vno - 1);
427     if (ret)
428 	krb5_err (context, 1, ret, "kadm5_log_set_version");
429 
430     ret = kadm5_log_nop (server_context);
431     if (ret)
432 	krb5_err (context, 1, ret, "kadm5_log_nop");
433 
434     ret = mydb->hdb_rename (context, mydb, server_context->db->hdb_name);
435     if (ret)
436 	krb5_err (context, 1, ret, "db->rename");
437 
438  cleanup:
439     krb5_data_free (&data);
440 
441     ret = mydb->hdb_close (context, mydb);
442     if (ret)
443 	krb5_err (context, 1, ret, "db->close");
444 
445     ret = mydb->hdb_destroy (context, mydb);
446     if (ret)
447 	krb5_err (context, 1, ret, "db->destroy");
448 
449     krb5_warnx(context, "receive complete database, version %ld", (long)vno);
450     return ret;
451 }
452 
453 static char *config_file;
454 static char *realm;
455 static int version_flag;
456 static int help_flag;
457 static char *keytab_str;
458 static char *port_str;
459 #ifdef SUPPORT_DETACH
460 static int detach_from_console = 0;
461 #endif
462 
463 static struct getargs args[] = {
464     { "config-file", 'c', arg_string, &config_file, NULL, NULL },
465     { "realm", 'r', arg_string, &realm, NULL, NULL },
466     { "keytab", 'k', arg_string, &keytab_str,
467       "keytab to get authentication from", "kspec" },
468     { "time-lost", 0, arg_string, &server_time_lost,
469       "time before server is considered lost", "time" },
470     { "port", 0, arg_string, &port_str,
471       "port ipropd-slave will connect to", "port"},
472 #ifdef SUPPORT_DETACH
473     { "detach", 0, arg_flag, &detach_from_console,
474       "detach from console", NULL },
475 #endif
476     { "hostname", 0, arg_string, rk_UNCONST(&slave_str),
477       "hostname of slave (if not same as hostname)", "hostname" },
478     { "version", 0, arg_flag, &version_flag, NULL, NULL },
479     { "help", 0, arg_flag, &help_flag, NULL, NULL }
480 };
481 
482 static int num_args = sizeof(args) / sizeof(args[0]);
483 
484 static void
485 usage(int status)
486 {
487     arg_printusage(args, num_args, NULL, "master");
488     exit(status);
489 }
490 
491 int
492 main(int argc, char **argv)
493 {
494     krb5_error_code ret;
495     krb5_context context;
496     krb5_auth_context auth_context;
497     void *kadm_handle;
498     kadm5_server_context *server_context;
499     kadm5_config_params conf;
500     int master_fd;
501     krb5_ccache ccache;
502     krb5_principal server;
503     char **files;
504     int optidx = 0;
505     time_t reconnect_min;
506     time_t backoff;
507     time_t reconnect_max;
508     time_t reconnect;
509     time_t before = 0;
510 
511     const char *master;
512 
513     setprogname(argv[0]);
514 
515     if(getarg(args, num_args, argc, argv, &optidx))
516 	usage(1);
517 
518     if(help_flag)
519 	usage(0);
520     if(version_flag) {
521 	print_version(NULL);
522 	exit(0);
523     }
524 
525     ret = krb5_init_context(&context);
526     if (ret)
527 	errx (1, "krb5_init_context failed: %d", ret);
528 
529     setup_signal();
530 
531     if (config_file == NULL) {
532 	if (asprintf(&config_file, "%s/kdc.conf", hdb_db_dir(context)) == -1
533 	    || config_file == NULL)
534 	    errx(1, "out of memory");
535     }
536 
537     ret = krb5_prepend_config_files_default(config_file, &files);
538     if (ret)
539 	krb5_err(context, 1, ret, "getting configuration files");
540 
541     ret = krb5_set_config_files(context, files);
542     krb5_free_config_files(files);
543     if (ret)
544 	krb5_err(context, 1, ret, "reading configuration files");
545 
546     argc -= optidx;
547     argv += optidx;
548 
549     if (argc != 1)
550 	usage(1);
551 
552     master = argv[0];
553 
554 #ifdef SUPPORT_DETACH
555     if (detach_from_console)
556 	daemon(0, 0);
557 #endif
558     pidfile (NULL);
559     krb5_openlog (context, "ipropd-slave", &log_facility);
560     krb5_set_warn_dest(context, log_facility);
561 
562     ret = krb5_kt_register(context, &hdb_kt_ops);
563     if(ret)
564 	krb5_err(context, 1, ret, "krb5_kt_register");
565 
566     time_before_lost = parse_time (server_time_lost,  "s");
567     if (time_before_lost < 0)
568 	krb5_errx (context, 1, "couldn't parse time: %s", server_time_lost);
569 
570     memset(&conf, 0, sizeof(conf));
571     if(realm) {
572 	conf.mask |= KADM5_CONFIG_REALM;
573 	conf.realm = realm;
574     }
575     ret = kadm5_init_with_password_ctx (context,
576 					KADM5_ADMIN_SERVICE,
577 					NULL,
578 					KADM5_ADMIN_SERVICE,
579 					&conf, 0, 0,
580 					&kadm_handle);
581     if (ret)
582 	krb5_err (context, 1, ret, "kadm5_init_with_password_ctx");
583 
584     server_context = (kadm5_server_context *)kadm_handle;
585 
586     ret = kadm5_log_init (server_context);
587     if (ret)
588 	krb5_err (context, 1, ret, "kadm5_log_init");
589 
590     get_creds(context, keytab_str, &ccache, master);
591 
592     ret = krb5_sname_to_principal (context, master, IPROP_NAME,
593 				   KRB5_NT_SRV_HST, &server);
594     if (ret)
595 	krb5_err (context, 1, ret, "krb5_sname_to_principal");
596 
597     auth_context = NULL;
598     master_fd = -1;
599 
600     krb5_appdefault_time(context, config_name, NULL, "reconnect-min",
601 			 10, &reconnect_min);
602     krb5_appdefault_time(context, config_name, NULL, "reconnect-max",
603 			 300, &reconnect_max);
604     krb5_appdefault_time(context, config_name, NULL, "reconnect-backoff",
605 			 10, &backoff);
606     reconnect = reconnect_min;
607 
608     while (!exit_flag) {
609 	time_t now, elapsed;
610 	int connected = FALSE;
611 
612 	now = time(NULL);
613 	elapsed = now - before;
614 
615 	if (elapsed < reconnect) {
616 	    time_t left = reconnect - elapsed;
617 	    krb5_warnx(context, "sleeping %d seconds before "
618 		       "retrying to connect", (int)left);
619 	    sleep(left);
620 	}
621 	before = now;
622 
623 	master_fd = connect_to_master (context, master, port_str);
624 	if (master_fd < 0)
625 	    goto retry;
626 
627 	reconnect = reconnect_min;
628 
629 	if (auth_context) {
630 	    krb5_auth_con_free(context, auth_context);
631 	    auth_context = NULL;
632 	    krb5_cc_destroy(context, ccache);
633 	    get_creds(context, keytab_str, &ccache, master);
634 	}
635 	ret = krb5_sendauth (context, &auth_context, &master_fd,
636 			     IPROP_VERSION, NULL, server,
637 			     AP_OPTS_MUTUAL_REQUIRED, NULL, NULL,
638 			     ccache, NULL, NULL, NULL);
639 	if (ret) {
640 	    krb5_warn (context, ret, "krb5_sendauth");
641 	    goto retry;
642 	}
643 
644 	krb5_warnx(context, "ipropd-slave started at version: %ld",
645 		   (long)server_context->log_context.version);
646 
647 	ret = ihave (context, auth_context, master_fd,
648 		     server_context->log_context.version);
649 	if (ret)
650 	    goto retry;
651 
652 	connected = TRUE;
653 
654 	while (connected && !exit_flag) {
655 	    krb5_data out;
656 	    krb5_storage *sp;
657 	    int32_t tmp;
658 	    fd_set readset;
659 	    struct timeval to;
660 
661 #ifndef NO_LIMIT_FD_SETSIZE
662 	    if (master_fd >= FD_SETSIZE)
663 		krb5_errx (context, 1, "fd too large");
664 #endif
665 
666 	    FD_ZERO(&readset);
667 	    FD_SET(master_fd, &readset);
668 
669 	    to.tv_sec = time_before_lost;
670 	    to.tv_usec = 0;
671 
672 	    ret = select (master_fd + 1,
673 			  &readset, NULL, NULL, &to);
674 	    if (ret < 0) {
675 		if (errno == EINTR)
676 		    continue;
677 		else
678 		    krb5_err (context, 1, errno, "select");
679 	    }
680 	    if (ret == 0)
681 		krb5_errx (context, 1, "server didn't send a message "
682 			   "in %d seconds", time_before_lost);
683 
684 	    ret = krb5_read_priv_message(context, auth_context, &master_fd, &out);
685 	    if (ret) {
686 		krb5_warn (context, ret, "krb5_read_priv_message");
687 		connected = FALSE;
688 		continue;
689 	    }
690 
691 	    sp = krb5_storage_from_mem (out.data, out.length);
692 	    krb5_ret_int32 (sp, &tmp);
693 	    switch (tmp) {
694 	    case FOR_YOU :
695 		receive (context, sp, server_context);
696 		ret = ihave (context, auth_context, master_fd,
697 			     server_context->log_context.version);
698 		if (ret)
699 		    connected = FALSE;
700 		break;
701 	    case TELL_YOU_EVERYTHING :
702 		ret = receive_everything (context, master_fd, server_context,
703 					  auth_context);
704 		if (ret)
705 		    connected = FALSE;
706 		break;
707 	    case ARE_YOU_THERE :
708 		send_im_here (context, master_fd, auth_context);
709 		break;
710 	    case NOW_YOU_HAVE :
711 	    case I_HAVE :
712 	    case ONE_PRINC :
713 	    case I_AM_HERE :
714 	    default :
715 		krb5_warnx (context, "Ignoring command %d", tmp);
716 		break;
717 	    }
718 	    krb5_storage_free (sp);
719 	    krb5_data_free (&out);
720 
721 	}
722     retry:
723 	if (connected == FALSE)
724 	    krb5_warnx (context, "disconnected for server");
725 	if (exit_flag)
726 	    krb5_warnx (context, "got an exit signal");
727 
728 	if (master_fd >= 0)
729 	    close(master_fd);
730 
731 	reconnect += backoff;
732 	if (reconnect > reconnect_max)
733 	    reconnect = reconnect_max;
734     }
735 
736     if (0);
737 #ifndef NO_SIGXCPU
738     else if(exit_flag == SIGXCPU)
739 	krb5_warnx(context, "%s CPU time limit exceeded", getprogname());
740 #endif
741     else if(exit_flag == SIGINT || exit_flag == SIGTERM)
742 	krb5_warnx(context, "%s terminated", getprogname());
743     else
744 	krb5_warnx(context, "%s unexpected exit reason: %ld",
745 		       getprogname(), (long)exit_flag);
746 
747     return 0;
748 }
749