xref: /netbsd-src/crypto/external/bsd/heimdal/dist/lib/kadm5/ipropd_slave.c (revision afab4e300d3a9fb07dd8c80daf53d0feb3345706)
1 /*	$NetBSD: ipropd_slave.c,v 1.4 2023/06/19 21:41:44 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 1.4 2023/06/19 21:41:44 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
connect_to_master(krb5_context context,const char * master,const char * port_str)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     /*
105      * We write message lengths separately from the payload, avoid Nagle
106      * delays.
107      */
108 #if defined(IPPROTO_TCP) && defined(TCP_NODELAY)
109     (void) setsockopt(s, IPPROTO_TCP, TCP_NODELAY,
110                       (void *)&one, sizeof(one));
111 #endif
112 
113     return s;
114 }
115 
116 static void
get_creds(krb5_context context,const char * keytab_str,krb5_ccache * cache,const char * serverhost)117 get_creds(krb5_context context, const char *keytab_str,
118 	  krb5_ccache *cache, const char *serverhost)
119 {
120     krb5_keytab keytab;
121     krb5_principal client;
122     krb5_error_code ret;
123     krb5_get_init_creds_opt *init_opts;
124     krb5_creds creds;
125     char *server;
126     char keytab_buf[256];
127     int aret;
128 
129     if (keytab_str == NULL) {
130 	ret = krb5_kt_default_name (context, keytab_buf, sizeof(keytab_buf));
131 	if (ret)
132 	    krb5_err (context, 1, ret, "krb5_kt_default_name");
133 	keytab_str = keytab_buf;
134     }
135 
136     ret = krb5_kt_resolve(context, keytab_str, &keytab);
137     if(ret)
138 	krb5_err(context, 1, ret, "%s", keytab_str);
139 
140 
141     ret = krb5_sname_to_principal (context, slave_str, IPROP_NAME,
142 				   KRB5_NT_SRV_HST, &client);
143     if (ret) krb5_err(context, 1, ret, "krb5_sname_to_principal");
144 
145     ret = krb5_get_init_creds_opt_alloc(context, &init_opts);
146     if (ret) krb5_err(context, 1, ret, "krb5_get_init_creds_opt_alloc");
147 
148     aret = asprintf (&server, "%s/%s", IPROP_NAME, serverhost);
149     if (aret == -1 || server == NULL)
150 	krb5_errx (context, 1, "malloc: no memory");
151 
152     ret = krb5_get_init_creds_keytab(context, &creds, client, keytab,
153 				     0, server, init_opts);
154     free (server);
155     krb5_get_init_creds_opt_free(context, init_opts);
156     if(ret) krb5_err(context, 1, ret, "krb5_get_init_creds");
157 
158     ret = krb5_kt_close(context, keytab);
159     if(ret) krb5_err(context, 1, ret, "krb5_kt_close");
160 
161     ret = krb5_cc_new_unique(context, krb5_cc_type_memory, NULL, cache);
162     if(ret) krb5_err(context, 1, ret, "krb5_cc_new_unique");
163 
164     ret = krb5_cc_initialize(context, *cache, creds.client);
165     if(ret) krb5_err(context, 1, ret, "krb5_cc_initialize");
166 
167     ret = krb5_cc_store_cred(context, *cache, &creds);
168     if(ret) krb5_err(context, 1, ret, "krb5_cc_store_cred");
169 
170     krb5_free_cred_contents(context, &creds);
171     krb5_free_principal(context, client);
172 }
173 
174 static krb5_error_code
ihave(krb5_context context,krb5_auth_context auth_context,int fd,uint32_t version)175 ihave(krb5_context context, krb5_auth_context auth_context,
176       int fd, uint32_t version)
177 {
178     int ret;
179     u_char buf[8];
180     krb5_storage *sp;
181     krb5_data data;
182 
183     sp = krb5_storage_from_mem(buf, 8);
184     ret = krb5_store_uint32(sp, I_HAVE);
185     if (ret == 0)
186         ret = krb5_store_uint32(sp, version);
187     krb5_storage_free(sp);
188     data.length = 8;
189     data.data   = buf;
190 
191     if (ret == 0) {
192         if (verbose)
193             krb5_warnx(context, "telling master we are at %u", version);
194 
195         ret = krb5_write_priv_message(context, auth_context, &fd, &data);
196         if (ret)
197             krb5_warn(context, ret, "krb5_write_message");
198     }
199     return ret;
200 }
201 
202 #ifndef EDQUOT
203 /* There's no EDQUOT on WIN32, for example */
204 #define EDQUOT ENOSPC
205 #endif
206 
207 static int
append_to_log_file(krb5_context context,kadm5_server_context * server_context,krb5_storage * sp,off_t start,ssize_t slen)208 append_to_log_file(krb5_context context,
209                    kadm5_server_context *server_context,
210                    krb5_storage *sp, off_t start, ssize_t slen)
211 {
212     size_t len;
213     ssize_t sret;
214     off_t log_off;
215     int ret, ret2;
216     void *buf;
217 
218     if (verbose)
219         krb5_warnx(context, "appending diffs to log");
220 
221     if (slen == 0)
222         return 0;
223     if (slen < 0)
224         return EINVAL;
225     len = slen;
226     if (len != slen)
227         return EOVERFLOW;
228 
229     buf = malloc(len);
230     if (buf == NULL && len != 0) {
231         krb5_warn(context, errno, "malloc: no memory");
232         return ENOMEM;
233     }
234 
235     if (krb5_storage_seek(sp, start, SEEK_SET) != start) {
236         krb5_errx(context, IPROPD_RESTART,
237                   "krb5_storage_seek() failed"); /* can't happen */
238     }
239     sret = krb5_storage_read(sp, buf, len);
240     if (sret < 0)
241         return errno;
242     if (len != (size_t)sret) {
243         /* Can't happen */
244         krb5_errx(context, IPROPD_RESTART,
245                   "short krb5_storage_read() from memory buffer");
246     }
247     log_off = lseek(server_context->log_context.log_fd, 0, SEEK_CUR);
248     if (log_off == -1)
249         return errno;
250 
251     /*
252      * Use net_write() so we get an errno if less that len bytes were
253      * written.
254      */
255     sret = net_write(server_context->log_context.log_fd, buf, len);
256     free(buf);
257     if (sret != slen)
258         ret = errno;
259     else
260         ret = fsync(server_context->log_context.log_fd);
261     if (ret == 0)
262         return 0;
263 
264     /*
265      * Attempt to recover from this.  First, truncate the log file
266      * and reset the fd offset.  Failure to do this -> unlink the
267      * log file and re-create it.  Since we're the slave, we ought to be
268      * able to recover from the log being unlinked...
269      */
270     if (ftruncate(server_context->log_context.log_fd, log_off) == -1 ||
271         lseek(server_context->log_context.log_fd, log_off, SEEK_SET) == -1) {
272         (void) kadm5_log_end(server_context);
273         if (unlink(server_context->log_context.log_file) == -1) {
274             krb5_err(context, IPROPD_FATAL, errno,
275                      "Failed to recover from failure to write log "
276                      "entries from master to disk");
277         }
278         ret2 = kadm5_log_init(server_context);
279         if (ret2) {
280             krb5_err(context, IPROPD_RESTART_SLOW, ret2,
281                      "Failed to initialize log to recover from "
282                      "failure to write log entries from master to disk");
283         }
284     }
285     if (ret == ENOSPC || ret == EDQUOT || ret == EFBIG) {
286         /* Unlink the file in these cases. */
287         krb5_warn(context, IPROPD_RESTART_SLOW,
288                   "Failed to write log entries from master to disk");
289         (void) kadm5_log_end(server_context);
290         if (unlink(server_context->log_context.log_file) == -1) {
291             krb5_err(context, IPROPD_FATAL, errno,
292                      "Failed to recover from failure to write log "
293                      "entries from master to disk");
294         }
295         ret2 = kadm5_log_init(server_context);
296         if (ret2) {
297             krb5_err(context, IPROPD_RESTART_SLOW, ret2,
298                      "Failed to initialize log to recover from "
299                      "failure to write log entries from master to disk");
300         }
301         return ret;
302     }
303     /*
304      * All other errors we treat as fatal here.  This includes, for
305      * example, EIO and EPIPE (sorry, can't log to pipes nor sockets).
306      */
307     krb5_err(context, IPROPD_FATAL, ret,
308              "Failed to write log entries from master to disk");
309 }
310 
311 static int
receive_loop(krb5_context context,krb5_storage * sp,kadm5_server_context * server_context)312 receive_loop (krb5_context context,
313 	      krb5_storage *sp,
314 	      kadm5_server_context *server_context)
315 {
316     int ret;
317     off_t left, right, off;
318     uint32_t len, vers;
319 
320     if (verbose)
321         krb5_warnx(context, "receiving diffs");
322 
323     /*
324      * Seek to the first entry in the message from the master that is
325      * past the current version of the local database.
326      */
327     do {
328 	uint32_t timestamp;
329         uint32_t op;
330 
331         if ((ret = krb5_ret_uint32(sp, &vers)) == HEIM_ERR_EOF) {
332             krb5_warnx(context, "master sent no new iprop entries");
333             return 0;
334         }
335 
336         /*
337          * TODO We could do more to validate the entries from the master
338          * here.  And we could use/reuse more kadm5_log_*() code here.
339          *
340          * Alternatively we should trust that the master sent us exactly
341          * what we needed and just write this to the log file and let
342          * kadm5_log_recover() do the rest.
343          */
344 	if (ret || krb5_ret_uint32(sp, &timestamp) != 0 ||
345             krb5_ret_uint32(sp, &op) != 0 ||
346             krb5_ret_uint32(sp, &len) != 0) {
347 
348             /*
349              * This shouldn't happen.  Reconnecting probably won't help
350              * if it does happen, but by reconnecting we get a chance to
351              * connect to a new master if a new one is configured.
352              */
353             krb5_warnx(context, "iprop entries from master were truncated");
354             return EINVAL;
355         }
356 	if (vers > server_context->log_context.version) {
357             break;
358         }
359         off = krb5_storage_seek(sp, 0, SEEK_CUR);
360         if (krb5_storage_seek(sp, len + 8, SEEK_CUR) != off + len + 8) {
361             krb5_warnx(context, "iprop entries from master were truncated");
362             return EINVAL;
363         }
364         if (verbose) {
365             krb5_warnx(context, "diff contains old log record version "
366                        "%u %lld %u length %u",
367                        vers, (long long)timestamp, op, len);
368         }
369     } while(vers <= server_context->log_context.version);
370 
371     /*
372      * Read the remaining entries into memory...
373      */
374     /* SEEK_CUR is a header into the first entry we care about */
375     left  = krb5_storage_seek(sp, -16, SEEK_CUR);
376     right = krb5_storage_seek(sp, 0, SEEK_END);
377     if (right - left < 24 + len) {
378         krb5_warnx(context, "iprop entries from master were truncated");
379         return EINVAL;
380     }
381 
382     /*
383      * ...and then write them out to the on-disk log.
384      */
385 
386     ret = append_to_log_file(context, server_context, sp, left, right - left);
387     if (ret)
388         return ret;
389 
390     /*
391      * Replay the new entries.
392      */
393     if (verbose)
394         krb5_warnx(context, "replaying entries from master");
395     ret = kadm5_log_recover(server_context, kadm_recover_replay);
396     if (ret) {
397         krb5_warn(context, ret, "replay failed");
398         return ret;
399     }
400 
401     ret = kadm5_log_get_version(server_context, &vers);
402     if (ret) {
403         krb5_warn(context, ret,
404                   "could not get log version after applying diffs!");
405         return ret;
406     }
407     if (verbose)
408         krb5_warnx(context, "slave at version %u", vers);
409 
410     if (vers != server_context->log_context.version) {
411         krb5_warnx(context, "slave's log_context version (%u) is "
412                    "inconsistent with log's version (%u)",
413                    server_context->log_context.version, vers);
414     }
415 
416     return 0;
417 }
418 
419 static int
receive(krb5_context context,krb5_storage * sp,kadm5_server_context * server_context)420 receive(krb5_context context,
421         krb5_storage *sp,
422         kadm5_server_context *server_context)
423 {
424     krb5_error_code ret, ret2;
425 
426     ret = server_context->db->hdb_open(context,
427 				       server_context->db,
428 				       O_RDWR | O_CREAT, 0600);
429     if (ret)
430         krb5_err(context, IPROPD_RESTART_SLOW, ret, "db->open");
431 
432     ret2 = receive_loop(context, sp, server_context);
433     if (ret2)
434 	krb5_warn(context, ret2, "receive from ipropd-master had errors");
435 
436     ret = server_context->db->hdb_close(context, server_context->db);
437     if (ret)
438         krb5_err(context, IPROPD_RESTART_SLOW, ret, "db->close");
439 
440     return ret2;
441 }
442 
443 static void
send_im_here(krb5_context context,int fd,krb5_auth_context auth_context)444 send_im_here(krb5_context context, int fd,
445 	     krb5_auth_context auth_context)
446 {
447     krb5_storage *sp;
448     krb5_data data;
449     krb5_error_code ret;
450 
451     ret = krb5_data_alloc(&data, 4);
452     if (ret)
453         krb5_err(context, IPROPD_RESTART, ret, "send_im_here");
454 
455     sp = krb5_storage_from_data (&data);
456     if (sp == NULL)
457         krb5_errx(context, IPROPD_RESTART, "krb5_storage_from_data");
458     ret = krb5_store_uint32(sp, I_AM_HERE);
459     krb5_storage_free(sp);
460 
461     if (ret == 0) {
462         ret = krb5_write_priv_message(context, auth_context, &fd, &data);
463         krb5_data_free(&data);
464 
465         if (ret)
466             krb5_err(context, IPROPD_RESTART, ret, "krb5_write_priv_message");
467 
468         if (verbose)
469             krb5_warnx(context, "pinged master");
470     }
471 
472     return;
473 }
474 
475 static void
reinit_log(krb5_context context,kadm5_server_context * server_context,uint32_t vno)476 reinit_log(krb5_context context,
477 	   kadm5_server_context *server_context,
478 	   uint32_t vno)
479 {
480     krb5_error_code ret;
481 
482     if (verbose)
483         krb5_warnx(context, "truncating log on slave");
484 
485     ret = kadm5_log_reinit(server_context, vno);
486     if (ret)
487         krb5_err(context, IPROPD_RESTART_SLOW, ret, "kadm5_log_reinit");
488 }
489 
490 
491 static krb5_error_code
receive_everything(krb5_context context,int fd,kadm5_server_context * server_context,krb5_auth_context auth_context)492 receive_everything(krb5_context context, int fd,
493 		   kadm5_server_context *server_context,
494 		   krb5_auth_context auth_context)
495 {
496     int ret;
497     krb5_data data;
498     uint32_t vno = 0;
499     uint32_t opcode;
500     krb5_storage *sp;
501 
502     char *dbname;
503     HDB *mydb;
504 
505     krb5_warnx(context, "receive complete database");
506 
507     ret = asprintf(&dbname, "%s-NEW", server_context->db->hdb_name);
508     if (ret == -1)
509         krb5_err(context, IPROPD_RESTART, ENOMEM, "asprintf");
510     ret = hdb_create(context, &mydb, dbname);
511     if(ret)
512         krb5_err(context, IPROPD_RESTART, ret, "hdb_create");
513     free(dbname);
514 
515     ret = hdb_set_master_keyfile(context,
516 				 mydb, server_context->config.stash_file);
517     if(ret)
518         krb5_err(context, IPROPD_RESTART, ret, "hdb_set_master_keyfile");
519 
520     /* I really want to use O_EXCL here, but given that I can't easily clean
521        up on error, I won't */
522     ret = mydb->hdb_open(context, mydb, O_RDWR | O_CREAT | O_TRUNC, 0600);
523     if (ret)
524         krb5_err(context, IPROPD_RESTART, ret, "db->open");
525 
526     (void) mydb->hdb_set_sync(context, mydb, 0);
527 
528     sp = NULL;
529     krb5_data_zero(&data);
530     do {
531 	ret = krb5_read_priv_message(context, auth_context, &fd, &data);
532 
533 	if (ret) {
534 	    krb5_warn(context, ret, "krb5_read_priv_message");
535 	    goto cleanup;
536 	}
537 
538 	sp = krb5_storage_from_data(&data);
539 	if (sp == NULL)
540 	    krb5_errx(context, IPROPD_RESTART, "krb5_storage_from_data");
541 	krb5_ret_uint32(sp, &opcode);
542 	if (opcode == ONE_PRINC) {
543 	    krb5_data fake_data;
544 	    hdb_entry_ex entry;
545 
546 	    krb5_storage_free(sp);
547 
548 	    fake_data.data   = (char *)data.data + 4;
549 	    fake_data.length = data.length - 4;
550 
551 	    memset(&entry, 0, sizeof(entry));
552 
553 	    ret = hdb_value2entry(context, &fake_data, &entry.entry);
554 	    if (ret)
555 		krb5_err(context, IPROPD_RESTART, ret, "hdb_value2entry");
556 	    ret = mydb->hdb_store(server_context->context,
557 				  mydb,
558 				  0, &entry);
559 	    if (ret)
560 		krb5_err(context, IPROPD_RESTART_SLOW, ret, "hdb_store");
561 
562 	    hdb_free_entry(context, &entry);
563 	    krb5_data_free(&data);
564 	} else if (opcode == NOW_YOU_HAVE)
565 	    ;
566 	else
567 	    krb5_errx(context, 1, "strange opcode %d", opcode);
568     } while (opcode == ONE_PRINC);
569 
570     if (opcode != NOW_YOU_HAVE)
571         krb5_errx(context, IPROPD_RESTART_SLOW,
572                   "receive_everything: strange %d", opcode);
573 
574     krb5_ret_uint32(sp, &vno);
575     krb5_storage_free(sp);
576 
577     reinit_log(context, server_context, vno);
578 
579     ret = mydb->hdb_set_sync(context, mydb, 1);
580     if (ret)
581         krb5_err(context, IPROPD_RESTART_SLOW, ret, "failed to sync the received HDB");
582     ret = mydb->hdb_close(context, mydb);
583     if (ret)
584         krb5_err(context, IPROPD_RESTART_SLOW, ret, "db->close");
585 
586     ret = mydb->hdb_rename(context, mydb, server_context->db->hdb_name);
587     if (ret)
588         krb5_err(context, IPROPD_RESTART_SLOW, ret, "db->rename");
589 
590 
591     return 0;
592 
593  cleanup:
594     krb5_data_free(&data);
595 
596     if (ret)
597         krb5_err(context, IPROPD_RESTART_SLOW, ret, "db->close");
598 
599     ret = mydb->hdb_destroy(context, mydb);
600     if (ret)
601         krb5_err(context, IPROPD_RESTART, ret, "db->destroy");
602 
603     krb5_warnx(context, "receive complete database, version %ld", (long)vno);
604     return ret;
605 }
606 
607 static void
608 slave_status(krb5_context context,
609 	     const char *file,
610 	     const char *status, ...)
611      __attribute__ ((__format__ (__printf__, 3, 4)));
612 
613 
614 static void
slave_status(krb5_context context,const char * file,const char * fmt,...)615 slave_status(krb5_context context,
616 	     const char *file,
617 	     const char *fmt, ...)
618 {
619     char *status;
620     char *fmt2;
621     va_list args;
622     int len;
623 
624     if (asprintf(&fmt2, "%s\n", fmt) == -1 || fmt2 == NULL) {
625         (void) unlink(file);
626         return;
627     }
628     va_start(args, fmt);
629     len = vasprintf(&status, fmt2, args);
630     free(fmt2);
631     va_end(args);
632     if (len < 0 || status == NULL) {
633 	(void) unlink(file);
634 	return;
635     }
636     krb5_warnx(context, "slave status change: %s", status);
637 
638     rk_dumpdata(file, status, len);
639     free(status);
640 }
641 
642 static void
is_up_to_date(krb5_context context,const char * file,kadm5_server_context * server_context)643 is_up_to_date(krb5_context context, const char *file,
644 	      kadm5_server_context *server_context)
645 {
646     krb5_error_code ret;
647     char buf[80];
648     ret = krb5_format_time(context, time(NULL), buf, sizeof(buf), 1);
649     if (ret) {
650 	unlink(file);
651 	return;
652     }
653     slave_status(context, file, "up-to-date with version: %lu at %s",
654 		 (unsigned long)server_context->log_context.version, buf);
655 }
656 
657 static char *status_file;
658 static char *config_file;
659 static char *realm;
660 static int version_flag;
661 static int help_flag;
662 static char *keytab_str;
663 static char *port_str;
664 static int detach_from_console;
665 static int daemon_child = -1;
666 
667 static struct getargs args[] = {
668     { "config-file", 'c', arg_string, &config_file, NULL, NULL },
669     { "realm", 'r', arg_string, &realm, NULL, NULL },
670     { "keytab", 'k', arg_string, &keytab_str,
671       "keytab to get authentication from", "kspec" },
672     { "time-lost", 0, arg_string, &server_time_lost,
673       "time before server is considered lost", "time" },
674     { "status-file", 0, arg_string, &status_file,
675       "file to write out status into", "file" },
676     { "port", 0, arg_string, &port_str,
677       "port ipropd-slave will connect to", "port"},
678     { "detach", 0, arg_flag, &detach_from_console,
679       "detach from console", NULL },
680     { "daemon-child",       0 ,      arg_integer, &daemon_child,
681       "private argument, do not use", NULL },
682     { "hostname", 0, arg_string, rk_UNCONST(&slave_str),
683       "hostname of slave (if not same as hostname)", "hostname" },
684     { "verbose", 0, arg_flag, &verbose, NULL, NULL },
685     { "version", 0, arg_flag, &version_flag, NULL, NULL },
686     { "help", 0, arg_flag, &help_flag, NULL, NULL }
687 };
688 
689 static int num_args = sizeof(args) / sizeof(args[0]);
690 
691 static void
usage(int status)692 usage(int status)
693 {
694     arg_printusage(args, num_args, NULL, "master");
695     exit(status);
696 }
697 
698 int
main(int argc,char ** argv)699 main(int argc, char **argv)
700 {
701     krb5_error_code ret, ret2;
702     krb5_context context;
703     krb5_auth_context auth_context;
704     void *kadm_handle;
705     kadm5_server_context *server_context;
706     kadm5_config_params conf;
707     int master_fd;
708     krb5_ccache ccache;
709     krb5_principal server;
710     char **files;
711     int optidx = 0;
712     time_t reconnect_min;
713     time_t backoff;
714     time_t reconnect_max;
715     time_t reconnect;
716     time_t before = 0;
717     int restarter_fd = -1;
718 
719     const char *master;
720 
721     setprogname(argv[0]);
722 
723     if (getarg(args, num_args, argc, argv, &optidx))
724 	usage(1);
725 
726     if (help_flag)
727 	usage(0);
728 
729     if (version_flag) {
730 	print_version(NULL);
731 	exit(0);
732     }
733 
734     if (detach_from_console && daemon_child == -1)
735         roken_detach_prep(argc, argv, "--daemon-child");
736     rk_pidfile(NULL);
737 
738     ret = krb5_init_context(&context);
739     if (ret)
740 	errx (1, "krb5_init_context failed: %d", ret);
741 
742     setup_signal();
743 
744     if (config_file == NULL) {
745 	if (asprintf(&config_file, "%s/kdc.conf", hdb_db_dir(context)) == -1
746 	    || config_file == NULL)
747 	    errx(1, "out of memory");
748     }
749 
750     ret = krb5_prepend_config_files_default(config_file, &files);
751     if (ret)
752 	krb5_err(context, 1, ret, "getting configuration files");
753 
754     ret = krb5_set_config_files(context, files);
755     krb5_free_config_files(files);
756     if (ret)
757 	krb5_err(context, 1, ret, "reading configuration files");
758 
759     argc -= optidx;
760     argv += optidx;
761 
762     if (argc != 1)
763 	usage(1);
764 
765     master = argv[0];
766 
767     if (status_file == NULL) {
768 	if (asprintf(&status_file,  "%s/ipropd-slave-status", hdb_db_dir(context)) < 0 || status_file == NULL)
769 	    krb5_errx(context, 1, "can't allocate status file buffer");
770     }
771 
772     krb5_openlog(context, "ipropd-slave", &log_facility);
773     krb5_set_warn_dest(context, log_facility);
774 
775     slave_status(context, status_file, "bootstrapping");
776 
777     ret = krb5_kt_register(context, &hdb_get_kt_ops);
778     if(ret)
779 	krb5_err(context, 1, ret, "krb5_kt_register");
780 
781     time_before_lost = parse_time (server_time_lost,  "s");
782     if (time_before_lost < 0)
783 	krb5_errx (context, 1, "couldn't parse time: %s", server_time_lost);
784 
785     slave_status(context, status_file, "getting credentials from keytab/database");
786 
787     memset(&conf, 0, sizeof(conf));
788     if(realm) {
789 	conf.mask |= KADM5_CONFIG_REALM;
790 	conf.realm = realm;
791     }
792     ret = kadm5_init_with_password_ctx (context,
793 					KADM5_ADMIN_SERVICE,
794 					NULL,
795 					KADM5_ADMIN_SERVICE,
796 					&conf, 0, 0,
797 					&kadm_handle);
798     if (ret)
799 	krb5_err (context, 1, ret, "kadm5_init_with_password_ctx");
800 
801     server_context = (kadm5_server_context *)kadm_handle;
802 
803     slave_status(context, status_file, "creating log file");
804 
805     ret = kadm5_log_init (server_context);
806     if (ret)
807 	krb5_err (context, 1, ret, "kadm5_log_init");
808 
809     get_creds(context, keytab_str, &ccache, master);
810 
811     ret = krb5_sname_to_principal (context, master, IPROP_NAME,
812 				   KRB5_NT_SRV_HST, &server);
813     if (ret)
814 	krb5_err (context, 1, ret, "krb5_sname_to_principal");
815 
816     auth_context = NULL;
817     master_fd = -1;
818 
819     krb5_appdefault_time(context, config_name, NULL, "reconnect-min",
820 			 10, &reconnect_min);
821     krb5_appdefault_time(context, config_name, NULL, "reconnect-max",
822 			 300, &reconnect_max);
823     krb5_appdefault_time(context, config_name, NULL, "reconnect-backoff",
824 			 10, &backoff);
825     reconnect = reconnect_min;
826 
827     slave_status(context, status_file, "ipropd-slave started");
828 
829     roken_detach_finish(NULL, daemon_child);
830     restarter_fd = restarter(context, NULL);
831 
832     while (!exit_flag) {
833         struct timeval to;
834 	time_t now, elapsed;
835         fd_set readset;
836 	int connected = FALSE;
837 
838 #ifndef NO_LIMIT_FD_SETSIZE
839         if (restarter_fd >= FD_SETSIZE)
840             krb5_errx(context, IPROPD_RESTART, "fd too large");
841 #endif
842 
843         FD_ZERO(&readset);
844         if (restarter_fd > -1)
845             FD_SET(restarter_fd, &readset);
846 
847 	now = time(NULL);
848 	elapsed = now - before;
849 
850 	if (elapsed < reconnect) {
851 	    time_t left = reconnect - elapsed;
852 	    krb5_warnx(context, "sleeping %d seconds before "
853 		       "retrying to connect", (int)left);
854             to.tv_sec = left;
855             to.tv_usec = 0;
856             if (select(restarter_fd + 1, &readset, NULL, NULL, &to) == 1) {
857                 exit_flag = SIGTERM;
858                 continue;
859             }
860 	}
861 	before = now;
862 
863 	slave_status(context, status_file, "connecting to master: %s\n", master);
864 
865 	master_fd = connect_to_master (context, master, port_str);
866 	if (master_fd < 0)
867 	    goto retry;
868 
869 	reconnect = reconnect_min;
870 
871 	if (auth_context) {
872 	    krb5_auth_con_free(context, auth_context);
873 	    auth_context = NULL;
874 	    krb5_cc_destroy(context, ccache);
875 	    get_creds(context, keytab_str, &ccache, master);
876 	}
877         if (verbose)
878             krb5_warnx(context, "authenticating to master");
879 	ret = krb5_sendauth (context, &auth_context, &master_fd,
880 			     IPROP_VERSION, NULL, server,
881 			     AP_OPTS_MUTUAL_REQUIRED, NULL, NULL,
882 			     ccache, NULL, NULL, NULL);
883 	if (ret) {
884 	    krb5_warn (context, ret, "krb5_sendauth");
885 	    goto retry;
886 	}
887 
888 	krb5_warnx(context, "ipropd-slave started at version: %ld",
889 		   (long)server_context->log_context.version);
890 
891 	ret = ihave(context, auth_context, master_fd,
892 		    server_context->log_context.version);
893 	if (ret)
894 	    goto retry;
895 
896 	connected = TRUE;
897 
898         if (verbose)
899             krb5_warnx(context, "connected to master");
900 
901 	slave_status(context, status_file, "connected to master, waiting instructions");
902 
903 	while (connected && !exit_flag) {
904 	    krb5_data out;
905 	    krb5_storage *sp;
906 	    uint32_t tmp;
907             int max_fd;
908 
909 #ifndef NO_LIMIT_FD_SETSIZE
910 	    if (master_fd >= FD_SETSIZE)
911                 krb5_errx(context, IPROPD_RESTART, "fd too large");
912             if (restarter_fd >= FD_SETSIZE)
913                 krb5_errx(context, IPROPD_RESTART, "fd too large");
914             max_fd = max(restarter_fd, master_fd);
915 #endif
916 
917 	    FD_ZERO(&readset);
918 	    FD_SET(master_fd, &readset);
919             if (restarter_fd != -1)
920                 FD_SET(restarter_fd, &readset);
921 
922 	    to.tv_sec = time_before_lost;
923 	    to.tv_usec = 0;
924 
925 	    ret = select (max_fd + 1,
926 			  &readset, NULL, NULL, &to);
927 	    if (ret < 0) {
928 		if (errno == EINTR)
929 		    continue;
930 		else
931 		    krb5_err (context, 1, errno, "select");
932 	    }
933 	    if (ret == 0) {
934 		krb5_warnx(context, "server didn't send a message "
935                            "in %d seconds", time_before_lost);
936 		connected = FALSE;
937 		continue;
938 	    }
939 
940             if (restarter_fd > -1 && FD_ISSET(restarter_fd, &readset)) {
941                 if (verbose)
942                     krb5_warnx(context, "slave restarter exited");
943                 exit_flag = SIGTERM;
944             }
945 
946             if (!FD_ISSET(master_fd, &readset))
947                 continue;
948 
949             if (verbose)
950                 krb5_warnx(context, "message from master");
951 
952 	    ret = krb5_read_priv_message(context, auth_context, &master_fd, &out);
953 	    if (ret) {
954 		krb5_warn(context, ret, "krb5_read_priv_message");
955 		connected = FALSE;
956 		continue;
957 	    }
958 
959 	    sp = krb5_storage_from_mem (out.data, out.length);
960             if (sp == NULL)
961                 krb5_err(context, IPROPD_RESTART, errno, "krb5_storage_from_mem");
962 	    ret = krb5_ret_uint32(sp, &tmp);
963             if (ret == HEIM_ERR_EOF) {
964                 krb5_warn(context, ret, "master sent zero-length message");
965                 connected = FALSE;
966                 continue;
967             }
968             if (ret != 0) {
969                 krb5_warn(context, ret, "couldn't read master's message");
970                 connected = FALSE;
971                 continue;
972             }
973 
974             ret = kadm5_log_init(server_context);
975             if (ret) {
976                 krb5_err(context, IPROPD_RESTART, ret, "kadm5_log_init while "
977                          "handling a message from the master");
978             }
979 	    switch (tmp) {
980 	    case FOR_YOU :
981                 if (verbose)
982                     krb5_warnx(context, "master sent us diffs");
983 		ret2 = receive(context, sp, server_context);
984                 if (ret2)
985                     krb5_warn(context, ret2,
986                               "receive from ipropd-master had errors");
987 		ret = ihave(context, auth_context, master_fd,
988 			    server_context->log_context.version);
989 		if (ret || ret2)
990 		    connected = FALSE;
991 
992                 /*
993                  * If it returns an error, receive() may nonetheless
994                  * have committed some entries successfully, so we must
995                  * update the slave_status even if there were errors.
996                  */
997                 is_up_to_date(context, status_file, server_context);
998 		break;
999 	    case TELL_YOU_EVERYTHING :
1000                 if (verbose)
1001                     krb5_warnx(context, "master sent us a full dump");
1002 		ret = receive_everything(context, master_fd, server_context,
1003 					 auth_context);
1004                 if (ret == 0) {
1005                     ret = ihave(context, auth_context, master_fd,
1006                                 server_context->log_context.version);
1007                 }
1008                 if (ret)
1009 		    connected = FALSE;
1010                 else
1011                     is_up_to_date(context, status_file, server_context);
1012 		break;
1013 	    case ARE_YOU_THERE :
1014                 if (verbose)
1015                     krb5_warnx(context, "master sent us a ping");
1016 		is_up_to_date(context, status_file, server_context);
1017                 /*
1018                  * We used to send an I_HAVE here.  But the master may send
1019                  * ARE_YOU_THERE messages in response to local, possibly-
1020                  * transient errors, and if that happens and we respond with an
1021                  * I_HAVE then we'll loop hard if the error was not transient.
1022                  *
1023                  * So we don't ihave() here.
1024                  */
1025 		send_im_here(context, master_fd, auth_context);
1026 		break;
1027 	    case YOU_HAVE_LAST_VERSION:
1028                 if (verbose)
1029                     krb5_warnx(context, "master tells us we are up to date");
1030 		is_up_to_date(context, status_file, server_context);
1031 		break;
1032 	    case NOW_YOU_HAVE :
1033 	    case I_HAVE :
1034 	    case ONE_PRINC :
1035 	    case I_AM_HERE :
1036 	    default :
1037 		krb5_warnx (context, "Ignoring command %d", tmp);
1038 		break;
1039 	    }
1040 	    krb5_storage_free (sp);
1041 	    krb5_data_free (&out);
1042 
1043 	}
1044 
1045 	slave_status(context, status_file, "disconnected from master");
1046     retry:
1047 	if (connected == FALSE)
1048 	    krb5_warnx (context, "disconnected for server");
1049 
1050 	if (exit_flag)
1051 	    krb5_warnx (context, "got an exit signal");
1052 
1053 	if (master_fd >= 0)
1054 	    close(master_fd);
1055 
1056 	reconnect += backoff;
1057 	if (reconnect > reconnect_max) {
1058 	    slave_status(context, status_file, "disconnected from master for a long time");
1059 	    reconnect = reconnect_max;
1060 	}
1061     }
1062 
1063     if (status_file) {
1064         /* XXX It'd be better to leave it saying we're not here */
1065 	unlink(status_file);
1066     }
1067 
1068     if (0);
1069 #ifndef NO_SIGXCPU
1070     else if(exit_flag == SIGXCPU)
1071 	krb5_warnx(context, "%s CPU time limit exceeded", getprogname());
1072 #endif
1073     else if(exit_flag == SIGINT || exit_flag == SIGTERM)
1074 	krb5_warnx(context, "%s terminated", getprogname());
1075     else
1076 	krb5_warnx(context, "%s unexpected exit reason: %ld",
1077 		       getprogname(), (long)exit_flag);
1078 
1079     return 0;
1080 }
1081