xref: /netbsd-src/crypto/external/bsd/heimdal/dist/lib/kadm5/ipropd_slave.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: ipropd_slave.c,v 1.2 2017/01/28 21:31:49 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1997 - 2008 Kungliga Tekniska Högskolan
5  * (Royal Institute of Technology, Stockholm, Sweden).
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * 3. Neither the name of the Institute nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include "iprop.h"
37 
38 __RCSID("$NetBSD: ipropd_slave.c,v 1.2 2017/01/28 21:31:49 christos Exp $");
39 
40 static const char *config_name = "ipropd-slave";
41 
42 static int verbose;
43 
44 static krb5_log_facility *log_facility;
45 static char five_min[] = "5 min";
46 static char *server_time_lost = five_min;
47 static int time_before_lost;
48 const char *slave_str = NULL;
49 
50 static int
51 connect_to_master (krb5_context context, const char *master,
52 		   const char *port_str)
53 {
54     char port[NI_MAXSERV];
55     struct addrinfo *ai, *a;
56     struct addrinfo hints;
57     int error;
58     int one = 1;
59     int s = -1;
60 
61     memset(&hints, 0, sizeof(hints));
62     hints.ai_socktype = SOCK_STREAM;
63 
64     if (port_str == NULL) {
65 	snprintf(port, sizeof(port), "%u", IPROP_PORT);
66 	port_str = port;
67     }
68 
69     error = getaddrinfo(master, port_str, &hints, &ai);
70     if (error) {
71 	krb5_warnx(context, "Failed to get address of to %s: %s",
72 		   master, gai_strerror(error));
73 	return -1;
74     }
75 
76     for (a = ai; a != NULL; a = a->ai_next) {
77 	char node[NI_MAXHOST];
78 	error = getnameinfo(a->ai_addr, a->ai_addrlen,
79 			    node, sizeof(node), NULL, 0, NI_NUMERICHOST);
80 	if (error)
81 	    strlcpy(node, "[unknown-addr]", sizeof(node));
82 
83 	s = socket(a->ai_family, a->ai_socktype, a->ai_protocol);
84 	if (s < 0)
85 	    continue;
86 	if (connect(s, a->ai_addr, a->ai_addrlen) < 0) {
87 	    krb5_warn(context, errno, "connection failed to %s[%s]",
88 		      master, node);
89 	    close(s);
90 	    continue;
91 	}
92 	krb5_warnx(context, "connection successful "
93 		   "to master: %s[%s]", master, node);
94 	break;
95     }
96     freeaddrinfo(ai);
97 
98     if (a == NULL)
99 	return -1;
100 
101     if (setsockopt(s, SOL_SOCKET, SO_KEEPALIVE, &one, sizeof(one)) < 0)
102         krb5_warn(context, errno, "setsockopt(SO_KEEPALIVE) failed");
103 
104     return s;
105 }
106 
107 static void
108 get_creds(krb5_context context, const char *keytab_str,
109 	  krb5_ccache *cache, const char *serverhost)
110 {
111     krb5_keytab keytab;
112     krb5_principal client;
113     krb5_error_code ret;
114     krb5_get_init_creds_opt *init_opts;
115     krb5_creds creds;
116     char *server;
117     char keytab_buf[256];
118     int aret;
119 
120     if (keytab_str == NULL) {
121 	ret = krb5_kt_default_name (context, keytab_buf, sizeof(keytab_buf));
122 	if (ret)
123 	    krb5_err (context, 1, ret, "krb5_kt_default_name");
124 	keytab_str = keytab_buf;
125     }
126 
127     ret = krb5_kt_resolve(context, keytab_str, &keytab);
128     if(ret)
129 	krb5_err(context, 1, ret, "%s", keytab_str);
130 
131 
132     ret = krb5_sname_to_principal (context, slave_str, IPROP_NAME,
133 				   KRB5_NT_SRV_HST, &client);
134     if (ret) krb5_err(context, 1, ret, "krb5_sname_to_principal");
135 
136     ret = krb5_get_init_creds_opt_alloc(context, &init_opts);
137     if (ret) krb5_err(context, 1, ret, "krb5_get_init_creds_opt_alloc");
138 
139     aret = asprintf (&server, "%s/%s", IPROP_NAME, serverhost);
140     if (aret == -1 || server == NULL)
141 	krb5_errx (context, 1, "malloc: no memory");
142 
143     ret = krb5_get_init_creds_keytab(context, &creds, client, keytab,
144 				     0, server, init_opts);
145     free (server);
146     krb5_get_init_creds_opt_free(context, init_opts);
147     if(ret) krb5_err(context, 1, ret, "krb5_get_init_creds");
148 
149     ret = krb5_kt_close(context, keytab);
150     if(ret) krb5_err(context, 1, ret, "krb5_kt_close");
151 
152     ret = krb5_cc_new_unique(context, krb5_cc_type_memory, NULL, cache);
153     if(ret) krb5_err(context, 1, ret, "krb5_cc_new_unique");
154 
155     ret = krb5_cc_initialize(context, *cache, creds.client);
156     if(ret) krb5_err(context, 1, ret, "krb5_cc_initialize");
157 
158     ret = krb5_cc_store_cred(context, *cache, &creds);
159     if(ret) krb5_err(context, 1, ret, "krb5_cc_store_cred");
160 
161     krb5_free_cred_contents(context, &creds);
162     krb5_free_principal(context, client);
163 }
164 
165 static krb5_error_code
166 ihave(krb5_context context, krb5_auth_context auth_context,
167       int fd, uint32_t version)
168 {
169     int ret;
170     u_char buf[8];
171     krb5_storage *sp;
172     krb5_data data;
173 
174     sp = krb5_storage_from_mem(buf, 8);
175     ret = krb5_store_uint32(sp, I_HAVE);
176     if (ret == 0)
177         ret = krb5_store_uint32(sp, version);
178     krb5_storage_free(sp);
179     data.length = 8;
180     data.data   = buf;
181 
182     if (ret == 0) {
183         if (verbose)
184             krb5_warnx(context, "telling master we are at %u", version);
185 
186         ret = krb5_write_priv_message(context, auth_context, &fd, &data);
187         if (ret)
188             krb5_warn(context, ret, "krb5_write_message");
189     }
190     return ret;
191 }
192 
193 #ifndef EDQUOT
194 /* There's no EDQUOT on WIN32, for example */
195 #define EDQUOT ENOSPC
196 #endif
197 
198 static int
199 append_to_log_file(krb5_context context,
200                    kadm5_server_context *server_context,
201                    krb5_storage *sp, off_t start, ssize_t slen)
202 {
203     size_t len;
204     ssize_t sret;
205     off_t log_off;
206     int ret, ret2;
207     void *buf;
208 
209     if (verbose)
210         krb5_warnx(context, "appending diffs to log");
211 
212     if (slen == 0)
213         return 0;
214     if (slen < 0)
215         return EINVAL;
216     len = slen;
217     if (len != slen)
218         return EOVERFLOW;
219 
220     buf = malloc(len);
221     if (buf == NULL && len != 0) {
222         krb5_warn(context, errno, "malloc: no memory");
223         return ENOMEM;
224     }
225 
226     if (krb5_storage_seek(sp, start, SEEK_SET) != start) {
227         krb5_errx(context, IPROPD_RESTART,
228                   "krb5_storage_seek() failed"); /* can't happen */
229     }
230     sret = krb5_storage_read(sp, buf, len);
231     if (sret < 0)
232         return errno;
233     if (len != (size_t)sret) {
234         /* Can't happen */
235         krb5_errx(context, IPROPD_RESTART,
236                   "short krb5_storage_read() from memory buffer");
237     }
238     log_off = lseek(server_context->log_context.log_fd, 0, SEEK_CUR);
239     if (log_off == -1)
240         return errno;
241 
242     /*
243      * Use net_write() so we get an errno if less that len bytes were
244      * written.
245      */
246     sret = net_write(server_context->log_context.log_fd, buf, len);
247     free(buf);
248     if (sret != slen)
249         ret = errno;
250     else
251         ret = fsync(server_context->log_context.log_fd);
252     if (ret == 0)
253         return 0;
254 
255     /*
256      * Attempt to recover from this.  First, truncate the log file
257      * and reset the fd offset.  Failure to do this -> unlink the
258      * log file and re-create it.  Since we're the slave, we ought to be
259      * able to recover from the log being unlinked...
260      */
261     if (ftruncate(server_context->log_context.log_fd, log_off) == -1 ||
262         lseek(server_context->log_context.log_fd, log_off, SEEK_SET) == -1) {
263         (void) kadm5_log_end(server_context);
264         if (unlink(server_context->log_context.log_file) == -1) {
265             krb5_err(context, IPROPD_FATAL, errno,
266                      "Failed to recover from failure to write log "
267                      "entries from master to disk");
268         }
269         ret2 = kadm5_log_init(server_context);
270         if (ret2) {
271             krb5_err(context, IPROPD_RESTART_SLOW, ret2,
272                      "Failed to initialize log to recover from "
273                      "failure to write log entries from master to disk");
274         }
275     }
276     if (ret == ENOSPC || ret == EDQUOT || ret == EFBIG) {
277         /* Unlink the file in these cases. */
278         krb5_warn(context, IPROPD_RESTART_SLOW,
279                   "Failed to write log entries from master to disk");
280         (void) kadm5_log_end(server_context);
281         if (unlink(server_context->log_context.log_file) == -1) {
282             krb5_err(context, IPROPD_FATAL, errno,
283                      "Failed to recover from failure to write log "
284                      "entries from master to disk");
285         }
286         ret2 = kadm5_log_init(server_context);
287         if (ret2) {
288             krb5_err(context, IPROPD_RESTART_SLOW, ret2,
289                      "Failed to initialize log to recover from "
290                      "failure to write log entries from master to disk");
291         }
292         return ret;
293     }
294     /*
295      * All other errors we treat as fatal here.  This includes, for
296      * example, EIO and EPIPE (sorry, can't log to pipes nor sockets).
297      */
298     krb5_err(context, IPROPD_FATAL, ret,
299              "Failed to write log entries from master to disk");
300 }
301 
302 static int
303 receive_loop (krb5_context context,
304 	      krb5_storage *sp,
305 	      kadm5_server_context *server_context)
306 {
307     int ret;
308     off_t left, right, off;
309     uint32_t len, vers;
310 
311     if (verbose)
312         krb5_warnx(context, "receiving diffs");
313 
314     /*
315      * Seek to the first entry in the message from the master that is
316      * past the current version of the local database.
317      */
318     do {
319 	uint32_t timestamp;
320         uint32_t op;
321 
322         if ((ret = krb5_ret_uint32(sp, &vers)) == HEIM_ERR_EOF) {
323             krb5_warnx(context, "master sent no new iprop entries");
324             return 0;
325         }
326 
327         /*
328          * TODO We could do more to validate the entries from the master
329          * here.  And we could use/reuse more kadm5_log_*() code here.
330          *
331          * Alternatively we should trust that the master sent us exactly
332          * what we needed and just write this to the log file and let
333          * kadm5_log_recover() do the rest.
334          */
335 	if (ret || krb5_ret_uint32(sp, &timestamp) != 0 ||
336             krb5_ret_uint32(sp, &op) != 0 ||
337             krb5_ret_uint32(sp, &len) != 0) {
338 
339             /*
340              * This shouldn't happen.  Reconnecting probably won't help
341              * if it does happen, but by reconnecting we get a chance to
342              * connect to a new master if a new one is configured.
343              */
344             krb5_warnx(context, "iprop entries from master were truncated");
345             return EINVAL;
346         }
347 	if (vers > server_context->log_context.version) {
348             break;
349         }
350         off = krb5_storage_seek(sp, 0, SEEK_CUR);
351         if (krb5_storage_seek(sp, len + 8, SEEK_CUR) != off + len + 8) {
352             krb5_warnx(context, "iprop entries from master were truncated");
353             return EINVAL;
354         }
355         if (verbose) {
356             krb5_warnx(context, "diff contains old log record version "
357                        "%u %lld %u length %u",
358                        vers, (long long)timestamp, op, len);
359         }
360     } while(vers <= server_context->log_context.version);
361 
362     /*
363      * Read the remaining entries into memory...
364      */
365     /* SEEK_CUR is a header into the first entry we care about */
366     left  = krb5_storage_seek(sp, -16, SEEK_CUR);
367     right = krb5_storage_seek(sp, 0, SEEK_END);
368     if (right - left < 24 + len) {
369         krb5_warnx(context, "iprop entries from master were truncated");
370         return EINVAL;
371     }
372 
373     /*
374      * ...and then write them out to the on-disk log.
375      */
376 
377     ret = append_to_log_file(context, server_context, sp, left, right - left);
378     if (ret)
379         return ret;
380 
381     /*
382      * Replay the new entries.
383      */
384     if (verbose)
385         krb5_warnx(context, "replaying entries from master");
386     ret = kadm5_log_recover(server_context, kadm_recover_replay);
387     if (ret) {
388         krb5_warn(context, ret, "replay failed");
389         return ret;
390     }
391 
392     ret = kadm5_log_get_version(server_context, &vers);
393     if (ret) {
394         krb5_warn(context, ret,
395                   "could not get log version after applying diffs!");
396         return ret;
397     }
398     if (verbose)
399         krb5_warnx(context, "slave at version %u", vers);
400 
401     if (vers != server_context->log_context.version) {
402         krb5_warnx(context, "slave's log_context version (%u) is "
403                    "inconsistent with log's version (%u)",
404                    server_context->log_context.version, vers);
405     }
406 
407     return 0;
408 }
409 
410 static int
411 receive(krb5_context context,
412         krb5_storage *sp,
413         kadm5_server_context *server_context)
414 {
415     krb5_error_code ret, ret2;
416 
417     ret = server_context->db->hdb_open(context,
418 				       server_context->db,
419 				       O_RDWR | O_CREAT, 0600);
420     if (ret)
421         krb5_err(context, IPROPD_RESTART_SLOW, ret, "db->open");
422 
423     ret2 = receive_loop(context, sp, server_context);
424     if (ret2)
425 	krb5_warn(context, ret2, "receive from ipropd-master had errors");
426 
427     ret = server_context->db->hdb_close(context, server_context->db);
428     if (ret)
429         krb5_err(context, IPROPD_RESTART_SLOW, ret, "db->close");
430 
431     return ret2;
432 }
433 
434 static void
435 send_im_here(krb5_context context, int fd,
436 	     krb5_auth_context auth_context)
437 {
438     krb5_storage *sp;
439     krb5_data data;
440     krb5_error_code ret;
441 
442     ret = krb5_data_alloc(&data, 4);
443     if (ret)
444         krb5_err(context, IPROPD_RESTART, ret, "send_im_here");
445 
446     sp = krb5_storage_from_data (&data);
447     if (sp == NULL)
448         krb5_errx(context, IPROPD_RESTART, "krb5_storage_from_data");
449     ret = krb5_store_uint32(sp, I_AM_HERE);
450     krb5_storage_free(sp);
451 
452     if (ret == 0) {
453         ret = krb5_write_priv_message(context, auth_context, &fd, &data);
454         krb5_data_free(&data);
455 
456         if (ret)
457             krb5_err(context, IPROPD_RESTART, ret, "krb5_write_priv_message");
458 
459         if (verbose)
460             krb5_warnx(context, "pinged master");
461     }
462 
463     return;
464 }
465 
466 static void
467 reinit_log(krb5_context context,
468 	   kadm5_server_context *server_context,
469 	   uint32_t vno)
470 {
471     krb5_error_code ret;
472 
473     if (verbose)
474         krb5_warnx(context, "truncating log on slave");
475 
476     ret = kadm5_log_reinit(server_context, vno);
477     if (ret)
478         krb5_err(context, IPROPD_RESTART_SLOW, ret, "kadm5_log_reinit");
479 }
480 
481 
482 static krb5_error_code
483 receive_everything(krb5_context context, int fd,
484 		   kadm5_server_context *server_context,
485 		   krb5_auth_context auth_context)
486 {
487     int ret;
488     krb5_data data;
489     uint32_t vno = 0;
490     uint32_t opcode;
491     krb5_storage *sp;
492 
493     char *dbname;
494     HDB *mydb;
495 
496     krb5_warnx(context, "receive complete database");
497 
498     ret = asprintf(&dbname, "%s-NEW", server_context->db->hdb_name);
499     if (ret == -1)
500         krb5_err(context, IPROPD_RESTART, ENOMEM, "asprintf");
501     ret = hdb_create(context, &mydb, dbname);
502     if(ret)
503         krb5_err(context, IPROPD_RESTART, ret, "hdb_create");
504     free(dbname);
505 
506     ret = hdb_set_master_keyfile(context,
507 				 mydb, server_context->config.stash_file);
508     if(ret)
509         krb5_err(context, IPROPD_RESTART, ret, "hdb_set_master_keyfile");
510 
511     /* I really want to use O_EXCL here, but given that I can't easily clean
512        up on error, I won't */
513     ret = mydb->hdb_open(context, mydb, O_RDWR | O_CREAT | O_TRUNC, 0600);
514     if (ret)
515         krb5_err(context, IPROPD_RESTART, ret, "db->open");
516 
517     sp = NULL;
518     krb5_data_zero(&data);
519     do {
520 	ret = krb5_read_priv_message(context, auth_context, &fd, &data);
521 
522 	if (ret) {
523 	    krb5_warn(context, ret, "krb5_read_priv_message");
524 	    goto cleanup;
525 	}
526 
527 	sp = krb5_storage_from_data(&data);
528 	if (sp == NULL)
529 	    krb5_errx(context, IPROPD_RESTART, "krb5_storage_from_data");
530 	krb5_ret_uint32(sp, &opcode);
531 	if (opcode == ONE_PRINC) {
532 	    krb5_data fake_data;
533 	    hdb_entry_ex entry;
534 
535 	    krb5_storage_free(sp);
536 
537 	    fake_data.data   = (char *)data.data + 4;
538 	    fake_data.length = data.length - 4;
539 
540 	    memset(&entry, 0, sizeof(entry));
541 
542 	    ret = hdb_value2entry(context, &fake_data, &entry.entry);
543 	    if (ret)
544 		krb5_err(context, IPROPD_RESTART, ret, "hdb_value2entry");
545 	    ret = mydb->hdb_store(server_context->context,
546 				  mydb,
547 				  0, &entry);
548 	    if (ret)
549 		krb5_err(context, IPROPD_RESTART_SLOW, ret, "hdb_store");
550 
551 	    hdb_free_entry(context, &entry);
552 	    krb5_data_free(&data);
553 	} else if (opcode == NOW_YOU_HAVE)
554 	    ;
555 	else
556 	    krb5_errx(context, 1, "strange opcode %d", opcode);
557     } while (opcode == ONE_PRINC);
558 
559     if (opcode != NOW_YOU_HAVE)
560         krb5_errx(context, IPROPD_RESTART_SLOW,
561                   "receive_everything: strange %d", opcode);
562 
563     krb5_ret_uint32(sp, &vno);
564     krb5_storage_free(sp);
565 
566     reinit_log(context, server_context, vno);
567 
568     ret = mydb->hdb_close(context, mydb);
569     if (ret)
570         krb5_err(context, IPROPD_RESTART_SLOW, ret, "db->close");
571 
572     ret = mydb->hdb_rename(context, mydb, server_context->db->hdb_name);
573     if (ret)
574         krb5_err(context, IPROPD_RESTART_SLOW, ret, "db->rename");
575 
576 
577     return 0;
578 
579  cleanup:
580     krb5_data_free(&data);
581 
582     if (ret)
583         krb5_err(context, IPROPD_RESTART_SLOW, ret, "db->close");
584 
585     ret = mydb->hdb_destroy(context, mydb);
586     if (ret)
587         krb5_err(context, IPROPD_RESTART, ret, "db->destroy");
588 
589     krb5_warnx(context, "receive complete database, version %ld", (long)vno);
590     return ret;
591 }
592 
593 static void
594 slave_status(krb5_context context,
595 	     const char *file,
596 	     const char *status, ...)
597      __attribute__ ((__format__ (__printf__, 3, 4)));
598 
599 
600 static void
601 slave_status(krb5_context context,
602 	     const char *file,
603 	     const char *fmt, ...)
604 {
605     char *status;
606     char *fmt2;
607     va_list args;
608     int len;
609 
610     if (asprintf(&fmt2, "%s\n", fmt) == -1 || fmt2 == NULL) {
611         (void) unlink(file);
612         return;
613     }
614     va_start(args, fmt);
615     len = vasprintf(&status, fmt2, args);
616     free(fmt2);
617     va_end(args);
618     if (len < 0 || status == NULL) {
619 	(void) unlink(file);
620 	return;
621     }
622     krb5_warnx(context, "slave status change: %s", status);
623 
624     rk_dumpdata(file, status, len);
625     free(status);
626 }
627 
628 static void
629 is_up_to_date(krb5_context context, const char *file,
630 	      kadm5_server_context *server_context)
631 {
632     krb5_error_code ret;
633     char buf[80];
634     ret = krb5_format_time(context, time(NULL), buf, sizeof(buf), 1);
635     if (ret) {
636 	unlink(file);
637 	return;
638     }
639     slave_status(context, file, "up-to-date with version: %lu at %s",
640 		 (unsigned long)server_context->log_context.version, buf);
641 }
642 
643 static char *status_file;
644 static char *config_file;
645 static char *realm;
646 static int version_flag;
647 static int help_flag;
648 static char *keytab_str;
649 static char *port_str;
650 static int detach_from_console;
651 static int daemon_child = -1;
652 
653 static struct getargs args[] = {
654     { "config-file", 'c', arg_string, &config_file, NULL, NULL },
655     { "realm", 'r', arg_string, &realm, NULL, NULL },
656     { "keytab", 'k', arg_string, &keytab_str,
657       "keytab to get authentication from", "kspec" },
658     { "time-lost", 0, arg_string, &server_time_lost,
659       "time before server is considered lost", "time" },
660     { "status-file", 0, arg_string, &status_file,
661       "file to write out status into", "file" },
662     { "port", 0, arg_string, &port_str,
663       "port ipropd-slave will connect to", "port"},
664     { "detach", 0, arg_flag, &detach_from_console,
665       "detach from console", NULL },
666     { "daemon-child",       0 ,      arg_integer, &daemon_child,
667       "private argument, do not use", NULL },
668     { "hostname", 0, arg_string, rk_UNCONST(&slave_str),
669       "hostname of slave (if not same as hostname)", "hostname" },
670     { "verbose", 0, arg_flag, &verbose, NULL, NULL },
671     { "version", 0, arg_flag, &version_flag, NULL, NULL },
672     { "help", 0, arg_flag, &help_flag, NULL, NULL }
673 };
674 
675 static int num_args = sizeof(args) / sizeof(args[0]);
676 
677 static void
678 usage(int status)
679 {
680     arg_printusage(args, num_args, NULL, "master");
681     exit(status);
682 }
683 
684 int
685 main(int argc, char **argv)
686 {
687     krb5_error_code ret, ret2;
688     krb5_context context;
689     krb5_auth_context auth_context;
690     void *kadm_handle;
691     kadm5_server_context *server_context;
692     kadm5_config_params conf;
693     int master_fd;
694     krb5_ccache ccache;
695     krb5_principal server;
696     char **files;
697     int optidx = 0;
698     time_t reconnect_min;
699     time_t backoff;
700     time_t reconnect_max;
701     time_t reconnect;
702     time_t before = 0;
703     int restarter_fd = -1;
704 
705     const char *master;
706 
707     setprogname(argv[0]);
708 
709     if (getarg(args, num_args, argc, argv, &optidx))
710 	usage(1);
711 
712     if (help_flag)
713 	usage(0);
714 
715     if (version_flag) {
716 	print_version(NULL);
717 	exit(0);
718     }
719 
720     if (detach_from_console && daemon_child == -1)
721         roken_detach_prep(argc, argv, "--daemon-child");
722     rk_pidfile(NULL);
723 
724     ret = krb5_init_context(&context);
725     if (ret)
726 	errx (1, "krb5_init_context failed: %d", ret);
727 
728     setup_signal();
729 
730     if (config_file == NULL) {
731 	if (asprintf(&config_file, "%s/kdc.conf", hdb_db_dir(context)) == -1
732 	    || config_file == NULL)
733 	    errx(1, "out of memory");
734     }
735 
736     ret = krb5_prepend_config_files_default(config_file, &files);
737     if (ret)
738 	krb5_err(context, 1, ret, "getting configuration files");
739 
740     ret = krb5_set_config_files(context, files);
741     krb5_free_config_files(files);
742     if (ret)
743 	krb5_err(context, 1, ret, "reading configuration files");
744 
745     argc -= optidx;
746     argv += optidx;
747 
748     if (argc != 1)
749 	usage(1);
750 
751     master = argv[0];
752 
753     if (status_file == NULL) {
754 	if (asprintf(&status_file,  "%s/ipropd-slave-status", hdb_db_dir(context)) < 0 || status_file == NULL)
755 	    krb5_errx(context, 1, "can't allocate status file buffer");
756     }
757 
758     krb5_openlog(context, "ipropd-slave", &log_facility);
759     krb5_set_warn_dest(context, log_facility);
760 
761     slave_status(context, status_file, "bootstrapping");
762 
763     ret = krb5_kt_register(context, &hdb_get_kt_ops);
764     if(ret)
765 	krb5_err(context, 1, ret, "krb5_kt_register");
766 
767     time_before_lost = parse_time (server_time_lost,  "s");
768     if (time_before_lost < 0)
769 	krb5_errx (context, 1, "couldn't parse time: %s", server_time_lost);
770 
771     slave_status(context, status_file, "getting credentials from keytab/database");
772 
773     memset(&conf, 0, sizeof(conf));
774     if(realm) {
775 	conf.mask |= KADM5_CONFIG_REALM;
776 	conf.realm = realm;
777     }
778     ret = kadm5_init_with_password_ctx (context,
779 					KADM5_ADMIN_SERVICE,
780 					NULL,
781 					KADM5_ADMIN_SERVICE,
782 					&conf, 0, 0,
783 					&kadm_handle);
784     if (ret)
785 	krb5_err (context, 1, ret, "kadm5_init_with_password_ctx");
786 
787     server_context = (kadm5_server_context *)kadm_handle;
788 
789     slave_status(context, status_file, "creating log file");
790 
791     ret = kadm5_log_init (server_context);
792     if (ret)
793 	krb5_err (context, 1, ret, "kadm5_log_init");
794 
795     get_creds(context, keytab_str, &ccache, master);
796 
797     ret = krb5_sname_to_principal (context, master, IPROP_NAME,
798 				   KRB5_NT_SRV_HST, &server);
799     if (ret)
800 	krb5_err (context, 1, ret, "krb5_sname_to_principal");
801 
802     auth_context = NULL;
803     master_fd = -1;
804 
805     krb5_appdefault_time(context, config_name, NULL, "reconnect-min",
806 			 10, &reconnect_min);
807     krb5_appdefault_time(context, config_name, NULL, "reconnect-max",
808 			 300, &reconnect_max);
809     krb5_appdefault_time(context, config_name, NULL, "reconnect-backoff",
810 			 10, &backoff);
811     reconnect = reconnect_min;
812 
813     slave_status(context, status_file, "ipropd-slave started");
814 
815     roken_detach_finish(NULL, daemon_child);
816     restarter_fd = restarter(context, NULL);
817 
818     while (!exit_flag) {
819         struct timeval to;
820 	time_t now, elapsed;
821         fd_set readset;
822 	int connected = FALSE;
823 
824 #ifndef NO_LIMIT_FD_SETSIZE
825         if (restarter_fd >= FD_SETSIZE)
826             krb5_errx(context, IPROPD_RESTART, "fd too large");
827 #endif
828 
829         FD_ZERO(&readset);
830         if (restarter_fd > -1)
831             FD_SET(restarter_fd, &readset);
832 
833 	now = time(NULL);
834 	elapsed = now - before;
835 
836 	if (elapsed < reconnect) {
837 	    time_t left = reconnect - elapsed;
838 	    krb5_warnx(context, "sleeping %d seconds before "
839 		       "retrying to connect", (int)left);
840             to.tv_sec = left;
841             to.tv_usec = 0;
842             if (select(restarter_fd + 1, &readset, NULL, NULL, &to) == 1) {
843                 exit_flag = SIGTERM;
844                 continue;
845             }
846 	}
847 	before = now;
848 
849 	slave_status(context, status_file, "connecting to master: %s\n", master);
850 
851 	master_fd = connect_to_master (context, master, port_str);
852 	if (master_fd < 0)
853 	    goto retry;
854 
855 	reconnect = reconnect_min;
856 
857 	if (auth_context) {
858 	    krb5_auth_con_free(context, auth_context);
859 	    auth_context = NULL;
860 	    krb5_cc_destroy(context, ccache);
861 	    get_creds(context, keytab_str, &ccache, master);
862 	}
863         if (verbose)
864             krb5_warnx(context, "authenticating to master");
865 	ret = krb5_sendauth (context, &auth_context, &master_fd,
866 			     IPROP_VERSION, NULL, server,
867 			     AP_OPTS_MUTUAL_REQUIRED, NULL, NULL,
868 			     ccache, NULL, NULL, NULL);
869 	if (ret) {
870 	    krb5_warn (context, ret, "krb5_sendauth");
871 	    goto retry;
872 	}
873 
874 	krb5_warnx(context, "ipropd-slave started at version: %ld",
875 		   (long)server_context->log_context.version);
876 
877 	ret = ihave(context, auth_context, master_fd,
878 		    server_context->log_context.version);
879 	if (ret)
880 	    goto retry;
881 
882 	connected = TRUE;
883 
884         if (verbose)
885             krb5_warnx(context, "connected to master");
886 
887 	slave_status(context, status_file, "connected to master, waiting instructions");
888 
889 	while (connected && !exit_flag) {
890 	    krb5_data out;
891 	    krb5_storage *sp;
892 	    uint32_t tmp;
893             int max_fd;
894 
895 #ifndef NO_LIMIT_FD_SETSIZE
896 	    if (master_fd >= FD_SETSIZE)
897                 krb5_errx(context, IPROPD_RESTART, "fd too large");
898             if (restarter_fd >= FD_SETSIZE)
899                 krb5_errx(context, IPROPD_RESTART, "fd too large");
900             max_fd = max(restarter_fd, master_fd);
901 #endif
902 
903 	    FD_ZERO(&readset);
904 	    FD_SET(master_fd, &readset);
905             if (restarter_fd != -1)
906                 FD_SET(restarter_fd, &readset);
907 
908 	    to.tv_sec = time_before_lost;
909 	    to.tv_usec = 0;
910 
911 	    ret = select (max_fd + 1,
912 			  &readset, NULL, NULL, &to);
913 	    if (ret < 0) {
914 		if (errno == EINTR)
915 		    continue;
916 		else
917 		    krb5_err (context, 1, errno, "select");
918 	    }
919 	    if (ret == 0) {
920 		krb5_warnx(context, "server didn't send a message "
921                            "in %d seconds", time_before_lost);
922 		connected = FALSE;
923 		continue;
924 	    }
925 
926             if (restarter_fd > -1 && FD_ISSET(restarter_fd, &readset)) {
927                 if (verbose)
928                     krb5_warnx(context, "slave restarter exited");
929                 exit_flag = SIGTERM;
930             }
931 
932             if (!FD_ISSET(master_fd, &readset))
933                 continue;
934 
935             if (verbose)
936                 krb5_warnx(context, "message from master");
937 
938 	    ret = krb5_read_priv_message(context, auth_context, &master_fd, &out);
939 	    if (ret) {
940 		krb5_warn(context, ret, "krb5_read_priv_message");
941 		connected = FALSE;
942 		continue;
943 	    }
944 
945 	    sp = krb5_storage_from_mem (out.data, out.length);
946             if (sp == NULL)
947                 krb5_err(context, IPROPD_RESTART, errno, "krb5_storage_from_mem");
948 	    ret = krb5_ret_uint32(sp, &tmp);
949             if (ret == HEIM_ERR_EOF) {
950                 krb5_warn(context, ret, "master sent zero-length message");
951                 connected = FALSE;
952                 continue;
953             }
954             if (ret != 0) {
955                 krb5_warn(context, ret, "couldn't read master's message");
956                 connected = FALSE;
957                 continue;
958             }
959 
960             ret = kadm5_log_init(server_context);
961             if (ret) {
962                 krb5_err(context, IPROPD_RESTART, ret, "kadm5_log_init while "
963                          "handling a message from the master");
964             }
965 	    switch (tmp) {
966 	    case FOR_YOU :
967                 if (verbose)
968                     krb5_warnx(context, "master sent us diffs");
969 		ret2 = receive(context, sp, server_context);
970                 if (ret2)
971                     krb5_warn(context, ret2,
972                               "receive from ipropd-master had errors");
973 		ret = ihave(context, auth_context, master_fd,
974 			    server_context->log_context.version);
975 		if (ret || ret2)
976 		    connected = FALSE;
977 
978                 /*
979                  * If it returns an error, receive() may nonetheless
980                  * have committed some entries successfully, so we must
981                  * update the slave_status even if there were errors.
982                  */
983                 is_up_to_date(context, status_file, server_context);
984 		break;
985 	    case TELL_YOU_EVERYTHING :
986                 if (verbose)
987                     krb5_warnx(context, "master sent us a full dump");
988 		ret = receive_everything(context, master_fd, server_context,
989 					 auth_context);
990                 if (ret == 0) {
991                     ret = ihave(context, auth_context, master_fd,
992                                 server_context->log_context.version);
993                 }
994                 if (ret)
995 		    connected = FALSE;
996                 else
997                     is_up_to_date(context, status_file, server_context);
998 		break;
999 	    case ARE_YOU_THERE :
1000                 if (verbose)
1001                     krb5_warnx(context, "master sent us a ping");
1002 		is_up_to_date(context, status_file, server_context);
1003                 ret = ihave(context, auth_context, master_fd,
1004                             server_context->log_context.version);
1005                 if (ret)
1006                     connected = FALSE;
1007 
1008 		send_im_here(context, master_fd, auth_context);
1009 		break;
1010 	    case YOU_HAVE_LAST_VERSION:
1011                 if (verbose)
1012                     krb5_warnx(context, "master tells us we are up to date");
1013 		is_up_to_date(context, status_file, server_context);
1014 		break;
1015 	    case NOW_YOU_HAVE :
1016 	    case I_HAVE :
1017 	    case ONE_PRINC :
1018 	    case I_AM_HERE :
1019 	    default :
1020 		krb5_warnx (context, "Ignoring command %d", tmp);
1021 		break;
1022 	    }
1023 	    krb5_storage_free (sp);
1024 	    krb5_data_free (&out);
1025 
1026 	}
1027 
1028 	slave_status(context, status_file, "disconnected from master");
1029     retry:
1030 	if (connected == FALSE)
1031 	    krb5_warnx (context, "disconnected for server");
1032 
1033 	if (exit_flag)
1034 	    krb5_warnx (context, "got an exit signal");
1035 
1036 	if (master_fd >= 0)
1037 	    close(master_fd);
1038 
1039 	reconnect += backoff;
1040 	if (reconnect > reconnect_max) {
1041 	    slave_status(context, status_file, "disconnected from master for a long time");
1042 	    reconnect = reconnect_max;
1043 	}
1044     }
1045 
1046     if (status_file) {
1047         /* XXX It'd be better to leave it saying we're not here */
1048 	unlink(status_file);
1049     }
1050 
1051     if (0);
1052 #ifndef NO_SIGXCPU
1053     else if(exit_flag == SIGXCPU)
1054 	krb5_warnx(context, "%s CPU time limit exceeded", getprogname());
1055 #endif
1056     else if(exit_flag == SIGINT || exit_flag == SIGTERM)
1057 	krb5_warnx(context, "%s terminated", getprogname());
1058     else
1059 	krb5_warnx(context, "%s unexpected exit reason: %ld",
1060 		       getprogname(), (long)exit_flag);
1061 
1062     return 0;
1063 }
1064