2 * Copyright (c) 2001 Kungliga Tekniska Högskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
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.
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.
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
34 #include "krb5_locl.h"
37 RCSID("$Id: krbhst.c,v 1.43.2.1 2003/04/22 15:00:38 lha Exp $");
40 string_to_proto(const char *string)
42 if(strcasecmp(string, "udp") == 0)
43 return KRB5_KRBHST_UDP;
44 else if(strcasecmp(string, "tcp") == 0)
45 return KRB5_KRBHST_TCP;
46 else if(strcasecmp(string, "http") == 0)
47 return KRB5_KRBHST_HTTP;
52 * set `res' and `count' to the result of looking up SRV RR in DNS for
53 * `proto', `proto', `realm' using `dns_type'.
54 * if `port' != 0, force that port number
57 static krb5_error_code
58 srv_find_realm(krb5_context context, krb5_krbhst_info ***res, int *count,
59 const char *realm, const char *dns_type,
60 const char *proto, const char *service, int port)
64 struct resource_record *rr;
69 proto_num = string_to_proto(proto);
71 krb5_set_error_string(context, "unknown protocol `%s'", proto);
75 if(proto_num == KRB5_KRBHST_HTTP)
76 def_port = ntohs(krb5_getportbyname (context, "http", "tcp", 80));
78 def_port = ntohs(krb5_getportbyname (context, service, proto, 88));
82 snprintf(domain, sizeof(domain), "_%s._%s.%s.", service, proto, realm);
84 r = dns_lookup(domain, dns_type);
88 return KRB5_KDC_UNREACH;
91 for(num_srv = 0, rr = r->head; rr; rr = rr->next)
95 *res = malloc(num_srv * sizeof(**res));
98 krb5_set_error_string(context, "malloc: out of memory");
104 for(num_srv = 0, rr = r->head; rr; rr = rr->next)
105 if(rr->type == T_SRV) {
106 krb5_krbhst_info *hi;
107 size_t len = strlen(rr->u.srv->target);
109 hi = calloc(1, sizeof(*hi) + len);
112 while(--num_srv >= 0)
113 free((*res)[num_srv]);
117 (*res)[num_srv++] = hi;
119 hi->proto = proto_num;
121 hi->def_port = def_port;
125 hi->port = rr->u.srv->port;
127 strlcpy(hi->hostname, rr->u.srv->target, len + 1);
137 struct krb5_krbhst_data {
141 int port; /* hardwired port number if != 0 */
145 #define KD_SRV_HTTP 8
146 #define KD_FALLBACK 16
147 #define KD_CONFIG_EXISTS 32
149 krb5_error_code (*get_next)(krb5_context, struct krb5_krbhst_data *,
152 unsigned int fallback_count;
154 struct krb5_krbhst_info *hosts, **index, **end;
158 krbhst_empty(const struct krb5_krbhst_data *kd)
160 return kd->index == &kd->hosts;
164 * parse `spec' into a krb5_krbhst_info, defaulting the port to `def_port'
165 * and forcing it to `port' if port != 0
168 static struct krb5_krbhst_info*
169 parse_hostspec(krb5_context context, const char *spec, int def_port, int port)
171 const char *p = spec;
172 struct krb5_krbhst_info *hi;
174 hi = calloc(1, sizeof(*hi) + strlen(spec));
178 hi->proto = KRB5_KRBHST_UDP;
180 if(strncmp(p, "http://", 7) == 0){
181 hi->proto = KRB5_KRBHST_HTTP;
183 } else if(strncmp(p, "http/", 5) == 0) {
184 hi->proto = KRB5_KRBHST_HTTP;
186 def_port = ntohs(krb5_getportbyname (context, "http", "tcp", 80));
187 }else if(strncmp(p, "tcp/", 4) == 0){
188 hi->proto = KRB5_KRBHST_TCP;
190 } else if(strncmp(p, "udp/", 4) == 0) {
194 if(strsep_copy(&p, ":", hi->hostname, strlen(spec) + 1) < 0) {
198 /* get rid of trailing /, and convert to lower case */
199 hi->hostname[strcspn(hi->hostname, "/")] = '\0';
200 strlwr(hi->hostname);
202 hi->port = hi->def_port = def_port;
205 hi->port = strtol(p, &end, 0);
217 free_krbhst_info(krb5_krbhst_info *hi)
220 freeaddrinfo(hi->ai);
225 append_host_hostinfo(struct krb5_krbhst_data *kd, struct krb5_krbhst_info *host)
227 struct krb5_krbhst_info *h;
229 for(h = kd->hosts; h; h = h->next)
230 if(h->proto == host->proto &&
231 h->port == host->port &&
232 strcmp(h->hostname, host->hostname) == 0) {
233 free_krbhst_info(host);
237 kd->end = &host->next;
240 static krb5_error_code
241 append_host_string(krb5_context context, struct krb5_krbhst_data *kd,
242 const char *host, int def_port, int port)
244 struct krb5_krbhst_info *hi;
246 hi = parse_hostspec(context, host, def_port, port);
250 append_host_hostinfo(kd, hi);
255 * return a readable representation of `host' in `hostname, hostlen'
259 krb5_krbhst_format_string(krb5_context context, const krb5_krbhst_info *host,
260 char *hostname, size_t hostlen)
262 const char *proto = "";
263 char portstr[7] = "";
264 if(host->proto == KRB5_KRBHST_TCP)
266 else if(host->proto == KRB5_KRBHST_HTTP)
268 if(host->port != host->def_port)
269 snprintf(portstr, sizeof(portstr), ":%d", host->port);
270 snprintf(hostname, hostlen, "%s%s%s", proto, host->hostname, portstr);
275 * create a getaddrinfo `hints' based on `proto'
279 make_hints(struct addrinfo *hints, int proto)
281 memset(hints, 0, sizeof(*hints));
282 hints->ai_family = AF_UNSPEC;
284 case KRB5_KRBHST_UDP :
285 hints->ai_socktype = SOCK_DGRAM;
287 case KRB5_KRBHST_HTTP :
288 case KRB5_KRBHST_TCP :
289 hints->ai_socktype = SOCK_STREAM;
295 * return an `struct addrinfo *' in `ai' corresponding to the information
296 * in `host'. free:ing is handled by krb5_krbhst_free.
300 krb5_krbhst_get_addrinfo(krb5_context context, krb5_krbhst_info *host,
301 struct addrinfo **ai)
303 struct addrinfo hints;
304 char portstr[NI_MAXSERV];
307 if (host->ai == NULL) {
308 make_hints(&hints, host->proto);
309 snprintf (portstr, sizeof(portstr), "%d", host->port);
310 ret = getaddrinfo(host->hostname, portstr, &hints, &host->ai);
312 return krb5_eai_to_heim_errno(ret, errno);
319 get_next(struct krb5_krbhst_data *kd, krb5_krbhst_info **host)
321 struct krb5_krbhst_info *hi = *kd->index;
324 kd->index = &(*kd->index)->next;
331 srv_get_hosts(krb5_context context, struct krb5_krbhst_data *kd,
332 const char *proto, const char *service)
334 krb5_krbhst_info **res;
337 srv_find_realm(context, &res, &count, kd->realm, "SRV", proto, service,
339 for(i = 0; i < count; i++)
340 append_host_hostinfo(kd, res[i]);
345 * read the configuration for `conf_string', defaulting to kd->def_port and
346 * forcing it to `kd->port' if kd->port != 0
350 config_get_hosts(krb5_context context, struct krb5_krbhst_data *kd,
351 const char *conf_string)
356 hostlist = krb5_config_get_strings(context, NULL,
357 "realms", kd->realm, conf_string, NULL);
361 kd->flags |= KD_CONFIG_EXISTS;
362 for(i = 0; hostlist && hostlist[i] != NULL; i++)
363 append_host_string(context, kd, hostlist[i], kd->def_port, kd->port);
365 krb5_config_free_strings(hostlist);
369 * as a fallback, look for `serv_string.kd->realm' (typically
370 * kerberos.REALM, kerberos-1.REALM, ...
371 * `port' is the default port for the service, and `proto' the
375 static krb5_error_code
376 fallback_get_hosts(krb5_context context, struct krb5_krbhst_data *kd,
377 const char *serv_string, int port, int proto)
382 struct addrinfo hints;
383 char portstr[NI_MAXSERV];
385 if(kd->fallback_count == 0)
386 asprintf(&host, "%s.%s.", serv_string, kd->realm);
388 asprintf(&host, "%s-%d.%s.",
389 serv_string, kd->fallback_count, kd->realm);
394 make_hints(&hints, proto);
395 snprintf(portstr, sizeof(portstr), "%d", port);
396 ret = getaddrinfo(host, portstr, &hints, &ai);
398 /* no more hosts, so we're done here */
400 kd->flags |= KD_FALLBACK;
402 struct krb5_krbhst_info *hi;
403 size_t hostlen = strlen(host);
405 hi = calloc(1, sizeof(*hi) + hostlen);
412 hi->port = hi->def_port = port;
414 memmove(hi->hostname, host, hostlen - 1);
415 hi->hostname[hostlen - 1] = '\0';
417 append_host_hostinfo(kd, hi);
418 kd->fallback_count++;
423 static krb5_error_code
424 kdc_get_next(krb5_context context,
425 struct krb5_krbhst_data *kd,
426 krb5_krbhst_info **host)
430 if((kd->flags & KD_CONFIG) == 0) {
431 config_get_hosts(context, kd, "kdc");
432 kd->flags |= KD_CONFIG;
433 if(get_next(kd, host))
437 if (kd->flags & KD_CONFIG_EXISTS)
438 return KRB5_KDC_UNREACH; /* XXX */
440 if(context->srv_lookup) {
441 if((kd->flags & KD_SRV_UDP) == 0) {
442 srv_get_hosts(context, kd, "udp", "kerberos");
443 kd->flags |= KD_SRV_UDP;
444 if(get_next(kd, host))
448 if((kd->flags & KD_SRV_TCP) == 0) {
449 srv_get_hosts(context, kd, "tcp", "kerberos");
450 kd->flags |= KD_SRV_TCP;
451 if(get_next(kd, host))
454 if((kd->flags & KD_SRV_HTTP) == 0) {
455 srv_get_hosts(context, kd, "http", "kerberos");
456 kd->flags |= KD_SRV_HTTP;
457 if(get_next(kd, host))
462 while((kd->flags & KD_FALLBACK) == 0) {
463 ret = fallback_get_hosts(context, kd, "kerberos",
464 kd->def_port, KRB5_KRBHST_UDP);
467 if(get_next(kd, host))
471 return KRB5_KDC_UNREACH; /* XXX */
474 static krb5_error_code
475 admin_get_next(krb5_context context,
476 struct krb5_krbhst_data *kd,
477 krb5_krbhst_info **host)
481 if((kd->flags & KD_CONFIG) == 0) {
482 config_get_hosts(context, kd, "admin_server");
483 kd->flags |= KD_CONFIG;
484 if(get_next(kd, host))
488 if (kd->flags & KD_CONFIG_EXISTS)
489 return KRB5_KDC_UNREACH; /* XXX */
491 if(context->srv_lookup) {
492 if((kd->flags & KD_SRV_TCP) == 0) {
493 srv_get_hosts(context, kd, "tcp", "kerberos-adm");
494 kd->flags |= KD_SRV_TCP;
495 if(get_next(kd, host))
501 && (kd->flags & KD_FALLBACK) == 0) {
502 ret = fallback_get_hosts(context, kd, "kerberos",
503 kd->def_port, KRB5_KRBHST_UDP);
506 kd->flags |= KD_FALLBACK;
507 if(get_next(kd, host))
511 return KRB5_KDC_UNREACH; /* XXX */
514 static krb5_error_code
515 kpasswd_get_next(krb5_context context,
516 struct krb5_krbhst_data *kd,
517 krb5_krbhst_info **host)
521 if((kd->flags & KD_CONFIG) == 0) {
522 config_get_hosts(context, kd, "kpasswd_server");
523 if(get_next(kd, host))
527 if (kd->flags & KD_CONFIG_EXISTS)
528 return KRB5_KDC_UNREACH; /* XXX */
530 if(context->srv_lookup) {
531 if((kd->flags & KD_SRV_UDP) == 0) {
532 srv_get_hosts(context, kd, "udp", "kpasswd");
533 kd->flags |= KD_SRV_UDP;
534 if(get_next(kd, host))
539 /* no matches -> try admin */
541 if (krbhst_empty(kd)) {
543 kd->port = kd->def_port;
544 kd->get_next = admin_get_next;
545 ret = (*kd->get_next)(context, kd, host);
547 (*host)->proto = KRB5_KRBHST_UDP;
551 return KRB5_KDC_UNREACH; /* XXX */
554 static krb5_error_code
555 krb524_get_next(krb5_context context,
556 struct krb5_krbhst_data *kd,
557 krb5_krbhst_info **host)
559 if((kd->flags & KD_CONFIG) == 0) {
560 config_get_hosts(context, kd, "krb524_server");
561 if(get_next(kd, host))
563 kd->flags |= KD_CONFIG;
566 if (kd->flags & KD_CONFIG_EXISTS)
567 return KRB5_KDC_UNREACH; /* XXX */
569 if(context->srv_lookup) {
570 if((kd->flags & KD_SRV_UDP) == 0) {
571 srv_get_hosts(context, kd, "udp", "krb524");
572 kd->flags |= KD_SRV_UDP;
573 if(get_next(kd, host))
577 if((kd->flags & KD_SRV_TCP) == 0) {
578 srv_get_hosts(context, kd, "tcp", "krb524");
579 kd->flags |= KD_SRV_TCP;
580 if(get_next(kd, host))
585 /* no matches -> try kdc */
587 if (krbhst_empty(kd)) {
589 kd->port = kd->def_port;
590 kd->get_next = kdc_get_next;
591 return (*kd->get_next)(context, kd, host);
594 return KRB5_KDC_UNREACH; /* XXX */
597 static struct krb5_krbhst_data*
598 common_init(krb5_context context,
601 struct krb5_krbhst_data *kd;
603 if((kd = calloc(1, sizeof(*kd))) == NULL)
606 if((kd->realm = strdup(realm)) == NULL) {
611 kd->end = kd->index = &kd->hosts;
616 * initialize `handle' to look for hosts of type `type' in realm `realm'
620 krb5_krbhst_init(krb5_context context,
623 krb5_krbhst_handle *handle)
625 struct krb5_krbhst_data *kd;
626 krb5_error_code (*get_next)(krb5_context, struct krb5_krbhst_data *,
627 krb5_krbhst_info **);
631 case KRB5_KRBHST_KDC:
632 get_next = kdc_get_next;
633 def_port = ntohs(krb5_getportbyname (context, "kerberos", "udp", 88));
635 case KRB5_KRBHST_ADMIN:
636 get_next = admin_get_next;
637 def_port = ntohs(krb5_getportbyname (context, "kerberos-adm",
640 case KRB5_KRBHST_CHANGEPW:
641 get_next = kpasswd_get_next;
642 def_port = ntohs(krb5_getportbyname (context, "kpasswd", "udp",
645 case KRB5_KRBHST_KRB524:
646 get_next = krb524_get_next;
647 def_port = ntohs(krb5_getportbyname (context, "krb524", "udp", 4444));
650 krb5_set_error_string(context, "unknown krbhst type (%u)", type);
653 if((kd = common_init(context, realm)) == NULL)
655 kd->get_next = get_next;
656 kd->def_port = def_port;
662 * return the next host information from `handle' in `host'
666 krb5_krbhst_next(krb5_context context,
667 krb5_krbhst_handle handle,
668 krb5_krbhst_info **host)
670 if(get_next(handle, host))
673 return (*handle->get_next)(context, handle, host);
677 * return the next host information from `handle' as a host name
678 * in `hostname' (or length `hostlen)
682 krb5_krbhst_next_as_string(krb5_context context,
683 krb5_krbhst_handle handle,
688 krb5_krbhst_info *host;
689 ret = krb5_krbhst_next(context, handle, &host);
692 return krb5_krbhst_format_string(context, host, hostname, hostlen);
697 krb5_krbhst_reset(krb5_context context, krb5_krbhst_handle handle)
699 handle->index = &handle->hosts;
703 krb5_krbhst_free(krb5_context context, krb5_krbhst_handle handle)
705 krb5_krbhst_info *h, *next;
710 for (h = handle->hosts; h != NULL; h = next) {
719 /* backwards compatibility ahead */
721 static krb5_error_code
722 gethostlist(krb5_context context, const char *realm,
723 unsigned int type, char ***hostlist)
727 krb5_krbhst_handle handle;
728 char host[MAXHOSTNAMELEN];
729 krb5_krbhst_info *hostinfo;
731 ret = krb5_krbhst_init(context, realm, type, &handle);
735 while(krb5_krbhst_next(context, handle, &hostinfo) == 0)
738 return KRB5_KDC_UNREACH;
739 *hostlist = calloc(nhost + 1, sizeof(**hostlist));
740 if(*hostlist == NULL) {
741 krb5_krbhst_free(context, handle);
745 krb5_krbhst_reset(context, handle);
747 while(krb5_krbhst_next_as_string(context, handle,
748 host, sizeof(host)) == 0) {
749 if(((*hostlist)[nhost++] = strdup(host)) == NULL) {
750 krb5_free_krbhst(context, *hostlist);
751 krb5_krbhst_free(context, handle);
755 (*hostlist)[nhost++] = NULL;
756 krb5_krbhst_free(context, handle);
761 * return an malloced list of kadmin-hosts for `realm' in `hostlist'
765 krb5_get_krb_admin_hst (krb5_context context,
766 const krb5_realm *realm,
769 return gethostlist(context, *realm, KRB5_KRBHST_ADMIN, hostlist);
773 * return an malloced list of changepw-hosts for `realm' in `hostlist'
777 krb5_get_krb_changepw_hst (krb5_context context,
778 const krb5_realm *realm,
781 return gethostlist(context, *realm, KRB5_KRBHST_CHANGEPW, hostlist);
785 * return an malloced list of 524-hosts for `realm' in `hostlist'
789 krb5_get_krb524hst (krb5_context context,
790 const krb5_realm *realm,
793 return gethostlist(context, *realm, KRB5_KRBHST_KRB524, hostlist);
798 * return an malloced list of KDC's for `realm' in `hostlist'
802 krb5_get_krbhst (krb5_context context,
803 const krb5_realm *realm,
806 return gethostlist(context, *realm, KRB5_KRBHST_KDC, hostlist);
810 * free all the memory allocated in `hostlist'
814 krb5_free_krbhst (krb5_context context,
819 for (p = hostlist; *p; ++p)