4 * Copyright 1990,1991 by the Massachusetts Institute of Technology.
7 * Export of this software from the United States of America may
8 * require a specific license from the United States Government.
9 * It is the responsibility of any person or organization contemplating
10 * export to obtain such a license before exporting.
12 * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
13 * distribute this software and its documentation for any purpose and
14 * without fee is hereby granted, provided that the above copyright
15 * notice appear in all copies and that both that copyright notice and
16 * this permission notice appear in supporting documentation, and that
17 * the name of M.I.T. not be used in advertising or publicity pertaining
18 * to distribution of the software without specific, written prior
19 * permission. M.I.T. makes no representations about the suitability of
20 * this software for any purpose. It is provided "as is" without express
21 * or implied warranty.
24 * KDC Routines to deal with TGS_REQ's
32 #include <sys/types.h>
33 #include <netinet/in.h>
35 #include <arpa/inet.h>
42 #include "adm_proto.h"
45 static void find_alternate_tgs PROTOTYPE((krb5_kdc_req *,
50 static krb5_error_code prepare_error_tgs PROTOTYPE((krb5_kdc_req *,
58 process_tgs_req(pkt, from, portnum, response)
60 const krb5_fulladdr *from; /* who sent it ? */
62 krb5_data **response; /* filled in with a response packet */
64 krb5_keyblock * subkey;
65 krb5_encrypt_block eblock;
66 krb5_kdc_req *request = 0;
69 krb5_enc_kdc_rep_part reply_encpart;
70 krb5_ticket ticket_reply, *header_ticket = 0;
72 krb5_enc_tkt_part enc_tkt_reply;
73 krb5_transited enc_tkt_transited;
75 krb5_error_code retval = 0;
78 krb5_timestamp kdc_time, authtime;
79 krb5_keyblock *session_key = 0;
80 krb5_timestamp until, rtime;
81 krb5_keyblock encrypting_key;
82 krb5_key_data *server_key;
83 char *cname = 0, *sname = 0, *tmp = 0, *fromstring = 0;
84 krb5_last_req_entry *nolrarray[2], nolrentry;
85 /* krb5_address *noaddrarray[1]; */
86 krb5_enctype useenctype;
87 int errcode, errcode2;
90 const char *status = 0;
92 retval = decode_krb5_tgs_req(pkt, &request);
97 * setup_server_realm() sets up the global realm-specific data pointer.
99 if ((retval = setup_server_realm(request->server)))
103 if (from->address->addrtype == ADDRTYPE_INET)
105 (char *) inet_ntoa(*(struct in_addr *)from->address->contents);
108 fromstring = "<unknown>";
110 if ((errcode = krb5_unparse_name(kdc_context, request->server, &sname))) {
111 status = "UNPARSING SERVER";
115 /* errcode = kdc_process_tgs_req(request, from, pkt, &req_authdat); */
116 errcode = kdc_process_tgs_req(request, from, pkt, &header_ticket, &subkey);
118 if (header_ticket && header_ticket->enc_part2 &&
119 (errcode2 = krb5_unparse_name(kdc_context,
120 header_ticket->enc_part2->client,
122 status = "UNPARSING CLIENT";
128 status = "PROCESS_TGS";
132 if (!header_ticket) {
133 status="UNEXPECTED NULL in header_ticket";
138 * We've already dealt with the AP_REQ authentication, so we can
139 * use header_ticket freely. The encrypted part (if any) has been
140 * decrypted with the session key.
143 authtime = header_ticket->enc_part2->times.authtime;
145 /* XXX make sure server here has the proper realm...taken from AP_REQ
149 if ((errcode = krb5_db_get_principal(kdc_context, request->server, &server,
151 status = "LOOKING_UP_SERVER";
157 status = "NON_UNIQUE_PRINCIPAL";
158 errcode = KRB5KDC_ERR_PRINCIPAL_NOT_UNIQUE;
160 } else if (nprincs != 1) {
162 * might be a request for a TGT for some other realm; we
163 * should do our best to find such a TGS in this db
165 if (firstpass && krb5_princ_size(kdc_context, request->server) == 2) {
166 krb5_data *server_1 = krb5_princ_component(kdc_context, request->server, 1);
167 krb5_data *tgs_1 = krb5_princ_component(kdc_context, tgs_server, 1);
169 if (server_1->length != tgs_1->length ||
170 memcmp(server_1->data, tgs_1->data, tgs_1->length)) {
171 krb5_db_free_principal(kdc_context, &server, nprincs);
172 find_alternate_tgs(request, &server, &more, &nprincs);
177 krb5_db_free_principal(kdc_context, &server, nprincs);
178 status = "UNKNOWN_SERVER";
179 errcode = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN;
183 if ((errcode = krb5_timeofday(kdc_context, &kdc_time))) {
184 status = "TIME_OF_DAY";
188 if ((retval = validate_tgs_request(request, server, header_ticket,
189 kdc_time, &status))) {
191 status = "UNKNOWN_REASON";
192 errcode = retval + ERROR_TABLE_BASE_krb5;
197 * We pick the session keytype here....
199 * Some special care needs to be taken in the user-to-user
200 * case, since we don't know what keytypes the application server
201 * which is doing user-to-user authentication can support. We
202 * know that it at least must be able to support the encryption
203 * type of the session key in the TGT, since otherwise it won't be
204 * able to decrypt the U2U ticket! So we use that in preference
208 if (isflagset(request->kdc_options, KDC_OPT_ENC_TKT_IN_SKEY)) {
209 krb5_keyblock * st_sealing_key;
210 krb5_kvno st_srv_kvno;
214 * Get the key for the second ticket, and decrypt it.
216 if ((errcode = kdc_get_server_key(request->second_ticket[st_idx],
219 status = "2ND_TKT_SERVER";
222 errcode = krb5_decrypt_tkt_part(kdc_context, st_sealing_key,
223 request->second_ticket[st_idx]);
224 krb5_free_keyblock(kdc_context, st_sealing_key);
226 status = "2ND_TKT_DECRYPT";
230 etype = request->second_ticket[st_idx]->enc_part2->session->enctype;
231 if (!valid_enctype(etype)) {
232 status = "BAD_ETYPE_IN_2ND_TKT";
233 errcode = KRB5KDC_ERR_ETYPE_NOSUPP;
237 for (i = 0; i < request->nktypes; i++) {
238 if (request->ktype[i] == etype) {
246 * Select the keytype for the ticket session key.
248 if ((useenctype == 0) &&
249 (useenctype = select_session_keytype(kdc_context, &server,
251 request->ktype)) == 0) {
252 /* unsupported ktype */
253 status = "BAD_ENCRYPTION_TYPE";
254 errcode = KRB5KDC_ERR_ETYPE_NOSUPP;
258 krb5_use_enctype(kdc_context, &eblock, useenctype);
259 errcode = krb5_random_key(kdc_context, &eblock,
260 krb5_enctype_array[useenctype]->random_sequence,
263 /* random key failed */
264 status = "RANDOM_KEY_FAILED";
268 ticket_reply.server = request->server; /* XXX careful for realm... */
270 enc_tkt_reply.flags = 0;
271 enc_tkt_reply.times.starttime = 0;
274 * Fix header_ticket's starttime; if it's zero, fill in the
277 if (!(header_ticket->enc_part2->times.starttime))
278 header_ticket->enc_part2->times.starttime =
279 header_ticket->enc_part2->times.authtime;
281 /* don't use new addresses unless forwarded, see below */
283 enc_tkt_reply.caddrs = header_ticket->enc_part2->caddrs;
284 /* noaddrarray[0] = 0; */
285 reply_encpart.caddrs = 0; /* optional...don't put it in */
287 /* It should be noted that local policy may affect the */
288 /* processing of any of these flags. For example, some */
289 /* realms may refuse to issue renewable tickets */
291 if (isflagset(request->kdc_options, KDC_OPT_FORWARDABLE))
292 setflag(enc_tkt_reply.flags, TKT_FLG_FORWARDABLE);
294 if (isflagset(request->kdc_options, KDC_OPT_FORWARDED)) {
295 setflag(enc_tkt_reply.flags, TKT_FLG_FORWARDED);
297 /* include new addresses in ticket & reply */
299 enc_tkt_reply.caddrs = request->addresses;
300 reply_encpart.caddrs = request->addresses;
302 if (isflagset(header_ticket->enc_part2->flags, TKT_FLG_FORWARDED))
303 setflag(enc_tkt_reply.flags, TKT_FLG_FORWARDED);
305 if (isflagset(request->kdc_options, KDC_OPT_PROXIABLE))
306 setflag(enc_tkt_reply.flags, TKT_FLG_PROXIABLE);
308 if (isflagset(request->kdc_options, KDC_OPT_PROXY)) {
309 setflag(enc_tkt_reply.flags, TKT_FLG_PROXY);
311 /* include new addresses in ticket & reply */
313 enc_tkt_reply.caddrs = request->addresses;
314 reply_encpart.caddrs = request->addresses;
317 if (isflagset(request->kdc_options, KDC_OPT_ALLOW_POSTDATE))
318 setflag(enc_tkt_reply.flags, TKT_FLG_MAY_POSTDATE);
320 if (isflagset(request->kdc_options, KDC_OPT_POSTDATED)) {
321 setflag(enc_tkt_reply.flags, TKT_FLG_POSTDATED);
322 setflag(enc_tkt_reply.flags, TKT_FLG_INVALID);
323 enc_tkt_reply.times.starttime = request->from;
325 enc_tkt_reply.times.starttime = kdc_time;
327 if (isflagset(request->kdc_options, KDC_OPT_VALIDATE)) {
328 /* BEWARE of allocation hanging off of ticket & enc_part2, it belongs
330 ticket_reply = *(header_ticket);
331 enc_tkt_reply = *(header_ticket->enc_part2);
332 clear(enc_tkt_reply.flags, TKT_FLG_INVALID);
335 if (isflagset(request->kdc_options, KDC_OPT_RENEW)) {
336 krb5_deltat old_life;
338 /* BEWARE of allocation hanging off of ticket & enc_part2, it belongs
340 ticket_reply = *(header_ticket);
341 enc_tkt_reply = *(header_ticket->enc_part2);
343 old_life = enc_tkt_reply.times.endtime - enc_tkt_reply.times.starttime;
345 enc_tkt_reply.times.starttime = kdc_time;
346 enc_tkt_reply.times.endtime =
347 min(header_ticket->enc_part2->times.renew_till,
348 kdc_time + old_life);
350 /* not a renew request */
351 enc_tkt_reply.times.starttime = kdc_time;
352 until = (request->till == 0) ? kdc_infinity : request->till;
353 enc_tkt_reply.times.endtime =
354 min(until, min(enc_tkt_reply.times.starttime + server.max_life,
355 min(enc_tkt_reply.times.starttime + max_life_for_realm,
356 header_ticket->enc_part2->times.endtime)));
357 if (isflagset(request->kdc_options, KDC_OPT_RENEWABLE_OK) &&
358 (enc_tkt_reply.times.endtime < request->till) &&
359 isflagset(header_ticket->enc_part2->flags,
360 TKT_FLG_RENEWABLE)) {
361 setflag(request->kdc_options, KDC_OPT_RENEWABLE);
364 header_ticket->enc_part2->times.renew_till);
367 rtime = (request->rtime == 0) ? kdc_infinity : request->rtime;
369 if (isflagset(request->kdc_options, KDC_OPT_RENEWABLE)) {
370 /* already checked above in policy check to reject request for a
371 renewable ticket using a non-renewable ticket */
372 setflag(enc_tkt_reply.flags, TKT_FLG_RENEWABLE);
373 enc_tkt_reply.times.renew_till =
375 min(header_ticket->enc_part2->times.renew_till,
376 enc_tkt_reply.times.starttime +
377 min(server.max_renewable_life,
378 max_renewable_life_for_realm)));
380 enc_tkt_reply.times.renew_till = 0;
384 * Set authtime to be the same as header_ticket's
386 enc_tkt_reply.times.authtime = header_ticket->enc_part2->times.authtime;
389 * Propagate the preauthentication flags through to the returned ticket.
391 if (isflagset(header_ticket->enc_part2->flags, TKT_FLG_PRE_AUTH))
392 setflag(enc_tkt_reply.flags, TKT_FLG_PRE_AUTH);
394 if (isflagset(header_ticket->enc_part2->flags, TKT_FLG_HW_AUTH))
395 setflag(enc_tkt_reply.flags, TKT_FLG_HW_AUTH);
397 /* starttime is optional, and treated as authtime if not present.
398 so we can nuke it if it matches */
399 if (enc_tkt_reply.times.starttime == enc_tkt_reply.times.authtime)
400 enc_tkt_reply.times.starttime = 0;
402 /* assemble any authorization data */
403 if (request->authorization_data.ciphertext.data) {
404 krb5_encrypt_block eblock;
407 /* decrypt the authdata in the request */
408 if (!valid_enctype(request->authorization_data.enctype)) {
409 status = "BAD_AUTH_ETYPE";
410 errcode = KRB5KDC_ERR_ETYPE_NOSUPP;
413 /* put together an eblock for this encryption */
415 krb5_use_enctype(kdc_context, &eblock,
416 request->authorization_data.enctype);
418 scratch.length = request->authorization_data.ciphertext.length;
420 malloc(request->authorization_data.ciphertext.length))) {
421 status = "AUTH_NOMEM";
424 /* do any necessary key pre-processing */
425 if ((errcode = krb5_process_key(kdc_context, &eblock,
426 header_ticket->enc_part2->session))) {
427 status = "AUTH_PROCESS_KEY";
432 /* call the encryption routine */
433 if ((errcode = krb5_decrypt(kdc_context, (krb5_pointer) request->authorization_data.ciphertext.data,
434 (krb5_pointer) scratch.data,
435 scratch.length, &eblock, 0))) {
436 status = "AUTH_ENCRYPT_FAIL";
437 (void) krb5_finish_key(kdc_context, &eblock);
441 if ((errcode = krb5_finish_key(kdc_context, &eblock))) {
442 status = "AUTH_FINISH_KEY";
446 /* scratch now has the authorization data, so we decode it */
447 errcode = decode_krb5_authdata(&scratch, &(request->unenc_authdata));
450 status = "AUTH_DECODE";
455 concat_authorization_data(request->unenc_authdata,
456 header_ticket->enc_part2->authorization_data,
457 &enc_tkt_reply.authorization_data))) {
458 status = "CONCAT_AUTH";
462 enc_tkt_reply.authorization_data =
463 header_ticket->enc_part2->authorization_data;
465 enc_tkt_reply.session = session_key;
466 enc_tkt_reply.client = header_ticket->enc_part2->client;
467 enc_tkt_reply.transited.tr_type = KRB5_DOMAIN_X500_COMPRESS;
468 enc_tkt_reply.transited.tr_contents = empty_string; /* equivalent of "" */
471 * Only add the realm of the presented tgt to the transited list if
472 * it is different than the local realm (cross-realm) and it is different
473 * than the realm of the client (since the realm of the client is already
474 * implicitly part of the transited list and should not be explicitly
478 /* realm compare is like strcmp, but knows how to deal with these args */
479 if (realm_compare(header_ticket->server, tgs_server) ||
480 realm_compare(header_ticket->server, enc_tkt_reply.client)) {
481 /* tgt issued by local realm or issued by realm of client */
482 enc_tkt_reply.transited = header_ticket->enc_part2->transited;
484 /* tgt issued by some other realm and not the realm of the client */
485 /* assemble new transited field into allocated storage */
486 if (header_ticket->enc_part2->transited.tr_type !=
487 KRB5_DOMAIN_X500_COMPRESS) {
488 status = "BAD_TRTYPE";
489 errcode = KRB5KDC_ERR_TRTYPE_NOSUPP;
492 enc_tkt_transited.tr_type = KRB5_DOMAIN_X500_COMPRESS;
493 enc_tkt_transited.tr_contents.data = 0;
494 enc_tkt_transited.tr_contents.length = 0;
495 enc_tkt_reply.transited = enc_tkt_transited;
497 add_to_transited(&header_ticket->enc_part2->transited.tr_contents,
498 &enc_tkt_reply.transited.tr_contents,
499 header_ticket->server,
500 enc_tkt_reply.client,
502 status = "ADD_TR_FAIL";
508 ticket_reply.enc_part2 = &enc_tkt_reply;
511 * If we are doing user-to-user authentication, then make sure
512 * that the client for the second ticket matches the request
513 * server, and then encrypt the ticket using the session key of
516 if (isflagset(request->kdc_options, KDC_OPT_ENC_TKT_IN_SKEY)) {
518 * Make sure the client for the second ticket matches
521 if (!krb5_principal_compare(kdc_context, request->server,
522 request->second_ticket[st_idx]->enc_part2->client)) {
523 if ((errcode = krb5_unparse_name(kdc_context,
524 request->second_ticket[st_idx]->enc_part2->client,
527 krb5_klog_syslog(LOG_INFO, "TGS_REQ %s(%d): 2ND_TKT_MISMATCH: authtime %d, %s for %s, 2nd tkt client %s",
528 fromstring, portnum, authtime, cname, sname,
529 tmp ? tmp : "<unknown>");
533 ticket_reply.enc_part.kvno = 0;
534 ticket_reply.enc_part.enctype =
535 request->second_ticket[st_idx]->enc_part2->session->enctype;
536 if ((errcode = krb5_encrypt_tkt_part(kdc_context,
537 request->second_ticket[st_idx]->enc_part2->session,
539 status = "2ND_TKT_ENCRYPT";
545 * Find the server key
547 if ((errcode = krb5_dbe_find_enctype(kdc_context, &server,
548 -1, /* ignore keytype */
549 -1, /* Ignore salttype */
550 0, /* Get highest kvno */
552 status = "FINDING_SERVER_KEY";
555 /* convert server.key into a real key (it may be encrypted
556 * in the database) */
557 if ((errcode = krb5_dbekd_decrypt_key_data(kdc_context,
559 server_key, &encrypting_key,
561 status = "DECRYPT_SERVER_KEY";
564 if ((encrypting_key.enctype == ENCTYPE_DES_CBC_CRC) &&
565 (isflagset(server.attributes, KRB5_KDB_SUPPORT_DESMD5)))
566 encrypting_key.enctype = ENCTYPE_DES_CBC_MD5;
567 ticket_reply.enc_part.kvno = server_key->key_data_kvno;
568 errcode = krb5_encrypt_tkt_part(kdc_context, &encrypting_key,
570 krb5_free_keyblock_contents(kdc_context, &encrypting_key);
572 status = "TKT_ENCRYPT";
577 /* Start assembling the response */
578 reply.msg_type = KRB5_TGS_REP;
579 reply.padata = 0; /* always */
580 reply.client = header_ticket->enc_part2->client;
581 reply.enc_part.kvno = 0; /* We are using the session key */
582 reply.ticket = &ticket_reply;
584 reply_encpart.session = session_key;
585 reply_encpart.nonce = request->nonce;
587 /* copy the time fields EXCEPT for authtime; its location
589 reply_encpart.times = enc_tkt_reply.times;
590 reply_encpart.times.authtime = header_ticket->enc_part2->times.authtime;
592 /* starttime is optional, and treated as authtime if not present.
593 so we can nuke it if it matches */
594 if (enc_tkt_reply.times.starttime == enc_tkt_reply.times.authtime)
595 enc_tkt_reply.times.starttime = 0;
597 nolrentry.lr_type = KRB5_LRQ_NONE;
599 nolrarray[0] = &nolrentry;
601 reply_encpart.last_req = nolrarray; /* not available for TGS reqs */
602 reply_encpart.key_exp = 0; /* ditto */
603 reply_encpart.flags = enc_tkt_reply.flags;
604 reply_encpart.server = ticket_reply.server;
606 /* use the session key in the ticket, unless there's a subsession key
609 reply.enc_part.enctype = subkey ? subkey->enctype :
610 header_ticket->enc_part2->session->enctype;
611 errcode = krb5_encode_kdc_rep(kdc_context, KRB5_TGS_REP, &reply_encpart,
613 header_ticket->enc_part2->session,
616 status = "ENCODE_KDC_REP";
621 memset(ticket_reply.enc_part.ciphertext.data, 0,
622 ticket_reply.enc_part.ciphertext.length);
623 free(ticket_reply.enc_part.ciphertext.data);
624 /* these parts are left on as a courtesy from krb5_encode_kdc_rep so we
625 can use them in raw form if needed. But, we don't... */
626 memset(reply.enc_part.ciphertext.data, 0,
627 reply.enc_part.ciphertext.length);
628 free(reply.enc_part.ciphertext.data);
632 krb5_klog_syslog(LOG_INFO, "TGS_REQ %s(%d): %s: authtime %d, %s for %s%s%s",
633 fromstring, portnum, status, authtime,
634 cname ? cname : "<unknown client>",
635 sname ? sname : "<unknown server>",
637 errcode ? error_message(errcode) : "");
639 errcode -= ERROR_TABLE_BASE_krb5;
640 if (errcode < 0 || errcode > 128)
641 errcode = KRB_ERR_GENERIC;
643 retval = prepare_error_tgs(request, header_ticket, errcode,
644 fromstring, response);
648 krb5_free_ticket(kdc_context, header_ticket);
650 krb5_free_kdc_req(kdc_context, request);
656 krb5_db_free_principal(kdc_context, &server, 1);
658 krb5_free_keyblock(kdc_context, session_key);
660 free(enc_tkt_reply.transited.tr_contents.data);
665 static krb5_error_code
666 prepare_error_tgs (request, ticket, error, ident, response)
667 register krb5_kdc_req *request;
671 krb5_data **response;
674 krb5_error_code retval;
677 errpkt.ctime = request->nonce;
680 if ((retval = krb5_us_timeofday(kdc_context, &errpkt.stime,
683 errpkt.error = error;
684 errpkt.server = request->server;
685 if (ticket && ticket->enc_part2)
686 errpkt.client = ticket->enc_part2->client;
689 errpkt.text.length = strlen(error_message(error+KRB5KDC_ERR_NONE))+1;
690 if (!(errpkt.text.data = malloc(errpkt.text.length)))
692 (void) strcpy(errpkt.text.data, error_message(error+KRB5KDC_ERR_NONE));
694 if (!(scratch = (krb5_data *)malloc(sizeof(*scratch)))) {
695 free(errpkt.text.data);
698 errpkt.e_data.length = 0;
699 errpkt.e_data.data = 0;
701 retval = krb5_mk_error(kdc_context, &errpkt, scratch);
702 free(errpkt.text.data);
708 * The request seems to be for a ticket-granting service somewhere else,
709 * but we don't have a ticket for the final TGS. Try to give the requestor
710 * some intermediate realm.
713 find_alternate_tgs(request, server, more, nprincs)
714 krb5_kdc_req *request;
715 krb5_db_entry *server;
719 krb5_error_code retval;
720 krb5_principal *plist, *pl2;
726 if ((retval = krb5_walk_realm_tree(kdc_context,
727 krb5_princ_realm(kdc_context, request->server),
728 krb5_princ_component(kdc_context, request->server, 1),
729 &plist, KRB5_REALM_BRANCH_CHAR)))
732 /* move to the end */
733 for (pl2 = plist; *pl2; pl2++);
735 /* the first entry in this array is for krbtgt/local@local, so we
737 while (--pl2 > plist) {
739 tmp = *krb5_princ_realm(kdc_context, *pl2);
740 krb5_princ_set_realm(kdc_context, *pl2,
741 krb5_princ_realm(kdc_context, tgs_server));
742 retval = krb5_db_get_principal(kdc_context, *pl2, server, nprincs, more);
743 krb5_princ_set_realm(kdc_context, *pl2, &tmp);
747 krb5_free_realm_tree(kdc_context, plist);
751 krb5_db_free_principal(kdc_context, server, *nprincs);
753 } else if (*nprincs == 1) {
755 krb5_principal tmpprinc;
758 tmp = *krb5_princ_realm(kdc_context, *pl2);
759 krb5_princ_set_realm(kdc_context, *pl2,
760 krb5_princ_realm(kdc_context, tgs_server));
761 if ((retval = krb5_copy_principal(kdc_context, *pl2, &tmpprinc))) {
762 krb5_db_free_principal(kdc_context, server, *nprincs);
763 krb5_princ_set_realm(kdc_context, *pl2, &tmp);
766 krb5_princ_set_realm(kdc_context, *pl2, &tmp);
768 krb5_free_principal(kdc_context, request->server);
769 request->server = tmpprinc;
770 if (krb5_unparse_name(kdc_context, request->server, &sname)) {
771 krb5_klog_syslog(LOG_INFO,
772 "TGS_REQ: issuing alternate <un-unparseable> TGT");
774 krb5_klog_syslog(LOG_INFO,
775 "TGS_REQ: issuing TGT %s", sname);
780 krb5_db_free_principal(kdc_context, server, *nprincs);
786 krb5_free_realm_tree(kdc_context, plist);