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
28 #include <krb5/krb5.h>
30 #include <krb5/los-proto.h>
31 #include <krb5/asn1.h>
32 #include <krb5/osconf.h>
33 #include <krb5/ext-proto.h>
38 #include <sys/types.h>
39 #include <netinet/in.h>
41 #include <arpa/inet.h>
50 static void find_alternate_tgs PROTOTYPE((krb5_kdc_req *,
55 static krb5_error_code prepare_error_tgs PROTOTYPE((krb5_kdc_req *,
63 process_tgs_req(pkt, from, is_secondary, response)
65 const krb5_fulladdr *from; /* who sent it ? */
67 krb5_data **response; /* filled in with a response packet */
69 krb5_kdc_req *request = 0;
72 krb5_enc_kdc_rep_part reply_encpart;
73 krb5_ticket ticket_reply, *header_ticket = 0;
74 krb5_tkt_authent *req_authdat = 0;
76 krb5_enc_tkt_part enc_tkt_reply;
77 krb5_transited enc_tkt_transited;
79 krb5_error_code retval = 0;
82 krb5_timestamp kdc_time, authtime;
83 krb5_keyblock *session_key = 0;
84 krb5_timestamp until, rtime;
85 krb5_keyblock encrypting_key;
86 char *cname = 0, *sname = 0, *tmp = 0, *fromstring = 0;
87 krb5_last_req_entry *nolrarray[2], nolrentry;
88 /* krb5_address *noaddrarray[1]; */
89 krb5_enctype useetype;
90 int errcode, errcode2;
101 retval = decode_krb5_tgs_req(pkt, &request);
106 if (from->address->addrtype == ADDRTYPE_INET)
108 (char *) inet_ntoa(*(struct in_addr *)from->address->contents);
111 fromstring = "<unknown>";
113 if (errcode = krb5_unparse_name(request->server, &sname)) {
114 status = "UNPARSING SERVER";
118 errcode = kdc_process_tgs_req(request, from, pkt, &req_authdat);
120 header_ticket = req_authdat->ticket;
122 if (header_ticket && header_ticket->enc_part2 &&
123 (errcode2 = krb5_unparse_name(header_ticket->enc_part2->client,
125 status = "UNPARSING CLIENT";
131 status = "PROCESS_TGS";
135 if (!header_ticket) {
136 status="UNEXPECTED NULL in header_ticket";
141 * We've already dealt with the AP_REQ authentication, so we can
142 * use header_ticket freely. The encrypted part (if any) has been
143 * decrypted with the session key.
146 authtime = header_ticket->enc_part2->times.authtime;
148 /* XXX make sure server here has the proper realm...taken from AP_REQ
152 if (retval = krb5_db_get_principal(request->server, &server, &nprincs,
155 "TGS_REQ: GET_PRINCIPAL: authtime %d, host %s, %s for %s (%s)",
156 authtime, fromstring, cname, sname, error_message(retval));
162 status = "NON_UNIQUE_PRINCIPAL";
163 errcode = KRB5KDC_ERR_PRINCIPAL_NOT_UNIQUE;
165 } else if (nprincs != 1) {
167 * might be a request for a TGT for some other realm; we
168 * should do our best to find such a TGS in this db
170 if (firstpass && krb5_princ_size(request->server) == 2) {
171 krb5_data *server_1 = krb5_princ_component(request->server, 1);
172 krb5_data *tgs_1 = krb5_princ_component(tgs_server, 1);
174 if (server_1->length != tgs_1->length ||
175 memcmp(server_1->data, tgs_1->data, tgs_1->length)) {
176 krb5_db_free_principal(&server, nprincs);
177 find_alternate_tgs(request, &server, &more, &nprincs);
182 krb5_db_free_principal(&server, nprincs);
183 status = "UNKNOWN_SERVER";
184 errcode = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN;
188 if (retval = krb5_timeofday(&kdc_time)) {
189 status = "TIME_OF_DAY";
193 if (retval = validate_tgs_request(request, server, header_ticket,
194 kdc_time, &status)) {
196 status = "UNKNOWN_REASON";
197 errcode = retval + ERROR_TABLE_BASE_krb5;
201 for (i = 0; i < request->netypes; i++)
202 if (valid_etype(request->etype[i]))
204 if (i == request->netypes) {
205 /* unsupported etype */
206 status = "BAD_ENCRYPTION_TYPE";
207 errcode = KRB5KDC_ERR_ETYPE_NOSUPP;
210 useetype = request->etype[i];
212 if (retval = (*(krb5_csarray[useetype]->system->random_key))(krb5_csarray[useetype]->random_sequence, &session_key)) {
213 /* random key failed */
214 status = "RANDOM_KEY_FAILED";
218 ticket_reply.server = request->server; /* XXX careful for realm... */
219 ticket_reply.enc_part.etype = useetype;
220 ticket_reply.enc_part.kvno = server.kvno;
222 enc_tkt_reply.flags = 0;
223 enc_tkt_reply.times.starttime = 0;
226 * Fix header_ticket's starttime; if it's zero, fill in the
229 if (!(header_ticket->enc_part2->times.starttime))
230 header_ticket->enc_part2->times.starttime =
231 header_ticket->enc_part2->times.authtime;
233 /* don't use new addresses unless forwarded, see below */
235 enc_tkt_reply.caddrs = header_ticket->enc_part2->caddrs;
236 /* noaddrarray[0] = 0; */
237 reply_encpart.caddrs = 0; /* optional...don't put it in */
239 /* It should be noted that local policy may affect the */
240 /* processing of any of these flags. For example, some */
241 /* realms may refuse to issue renewable tickets */
243 if (isflagset(request->kdc_options, KDC_OPT_FORWARDABLE))
244 setflag(enc_tkt_reply.flags, TKT_FLG_FORWARDABLE);
246 if (isflagset(request->kdc_options, KDC_OPT_FORWARDED)) {
247 setflag(enc_tkt_reply.flags, TKT_FLG_FORWARDED);
249 /* include new addresses in ticket & reply */
251 enc_tkt_reply.caddrs = request->addresses;
252 reply_encpart.caddrs = request->addresses;
254 if (isflagset(header_ticket->enc_part2->flags, TKT_FLG_FORWARDED))
255 setflag(enc_tkt_reply.flags, TKT_FLG_FORWARDED);
257 if (isflagset(request->kdc_options, KDC_OPT_PROXIABLE))
258 setflag(enc_tkt_reply.flags, TKT_FLG_PROXIABLE);
260 if (isflagset(request->kdc_options, KDC_OPT_PROXY)) {
261 setflag(enc_tkt_reply.flags, TKT_FLG_PROXY);
263 /* include new addresses in ticket & reply */
265 enc_tkt_reply.caddrs = request->addresses;
266 reply_encpart.caddrs = request->addresses;
269 if (isflagset(request->kdc_options, KDC_OPT_ALLOW_POSTDATE))
270 setflag(enc_tkt_reply.flags, TKT_FLG_MAY_POSTDATE);
272 if (isflagset(request->kdc_options, KDC_OPT_POSTDATED)) {
273 setflag(enc_tkt_reply.flags, TKT_FLG_POSTDATED);
274 setflag(enc_tkt_reply.flags, TKT_FLG_INVALID);
275 enc_tkt_reply.times.starttime = request->from;
277 enc_tkt_reply.times.starttime = kdc_time;
279 if (isflagset(request->kdc_options, KDC_OPT_VALIDATE)) {
280 /* BEWARE of allocation hanging off of ticket & enc_part2, it belongs
282 ticket_reply = *(header_ticket);
283 enc_tkt_reply = *(header_ticket->enc_part2);
284 clear(enc_tkt_reply.flags, TKT_FLG_INVALID);
287 if (isflagset(request->kdc_options, KDC_OPT_RENEW)) {
288 krb5_deltat old_life;
290 /* BEWARE of allocation hanging off of ticket & enc_part2, it belongs
292 ticket_reply = *(header_ticket);
293 enc_tkt_reply = *(header_ticket->enc_part2);
295 old_life = enc_tkt_reply.times.endtime - enc_tkt_reply.times.starttime;
297 enc_tkt_reply.times.starttime = kdc_time;
298 enc_tkt_reply.times.endtime =
299 min(header_ticket->enc_part2->times.renew_till,
300 kdc_time + old_life);
302 /* not a renew request */
303 enc_tkt_reply.times.starttime = kdc_time;
304 until = (request->till == 0) ? kdc_infinity : request->till;
305 enc_tkt_reply.times.endtime =
306 min(until, min(enc_tkt_reply.times.starttime + server.max_life,
307 min(enc_tkt_reply.times.starttime + max_life_for_realm,
308 header_ticket->enc_part2->times.endtime)));
309 if (isflagset(request->kdc_options, KDC_OPT_RENEWABLE_OK) &&
310 (enc_tkt_reply.times.endtime < request->till) &&
311 isflagset(header_ticket->enc_part2->flags,
312 TKT_FLG_RENEWABLE)) {
313 setflag(request->kdc_options, KDC_OPT_RENEWABLE);
316 header_ticket->enc_part2->times.renew_till);
319 rtime = (request->rtime == 0) ? kdc_infinity : request->rtime;
321 if (isflagset(request->kdc_options, KDC_OPT_RENEWABLE)) {
322 /* already checked above in policy check to reject request for a
323 renewable ticket using a non-renewable ticket */
324 setflag(enc_tkt_reply.flags, TKT_FLG_RENEWABLE);
325 enc_tkt_reply.times.renew_till =
327 min(header_ticket->enc_part2->times.renew_till,
328 enc_tkt_reply.times.starttime +
329 min(server.max_renewable_life,
330 max_renewable_life_for_realm)));
332 enc_tkt_reply.times.renew_till = 0;
336 * Set authtime to be the same as header_ticket's
338 enc_tkt_reply.times.authtime = header_ticket->enc_part2->times.authtime;
341 * Propagate the preauthentication flags through to the returned ticket.
343 if (isflagset(header_ticket->enc_part2->flags, TKT_FLG_PRE_AUTH))
344 setflag(enc_tkt_reply.flags, TKT_FLG_PRE_AUTH);
346 if (isflagset(header_ticket->enc_part2->flags, TKT_FLG_HW_AUTH))
347 setflag(enc_tkt_reply.flags, TKT_FLG_HW_AUTH);
349 /* starttime is optional, and treated as authtime if not present.
350 so we can nuke it if it matches */
351 if (enc_tkt_reply.times.starttime == enc_tkt_reply.times.authtime)
352 enc_tkt_reply.times.starttime = 0;
354 /* assemble any authorization data */
355 if (request->authorization_data.ciphertext.data) {
356 krb5_encrypt_block eblock;
359 /* decrypt the authdata in the request */
360 if (!valid_etype(request->authorization_data.etype)) {
361 status = "BAD_AUTH_ETYPE";
362 errcode = KRB5KDC_ERR_ETYPE_NOSUPP;
365 /* put together an eblock for this encryption */
367 krb5_use_cstype(&eblock, request->authorization_data.etype);
369 scratch.length = request->authorization_data.ciphertext.length;
371 malloc(request->authorization_data.ciphertext.length))) {
372 status = "AUTH_NOMEM";
375 /* do any necessary key pre-processing */
376 if (retval = krb5_process_key(&eblock,
377 header_ticket->enc_part2->session)) {
378 status = "AUTH_PROCESS_KEY";
383 /* call the encryption routine */
384 if (retval = krb5_decrypt((krb5_pointer) request->authorization_data.ciphertext.data,
385 (krb5_pointer) scratch.data,
386 scratch.length, &eblock, 0)) {
387 status = "AUTH_ENCRYPT_FAIL";
388 (void) krb5_finish_key(&eblock);
392 if (retval = krb5_finish_key(&eblock)) {
393 status = "AUTH_FINISH_KEY";
397 /* scratch now has the authorization data, so we decode it */
398 #ifdef KRB5_USE_ISODE
399 retval = decode_krb5_authdata(&scratch, request->unenc_authdata);
401 retval = decode_krb5_authdata(&scratch, &(request->unenc_authdata));
405 status = "AUTH_DECODE";
410 concat_authorization_data(request->unenc_authdata,
411 header_ticket->enc_part2->authorization_data,
412 &enc_tkt_reply.authorization_data)) {
413 status = "CONCAT_AUTH";
417 enc_tkt_reply.authorization_data =
418 header_ticket->enc_part2->authorization_data;
420 enc_tkt_reply.session = session_key;
421 enc_tkt_reply.client = header_ticket->enc_part2->client;
422 enc_tkt_reply.transited.tr_type = KRB5_DOMAIN_X500_COMPRESS;
423 enc_tkt_reply.transited.tr_contents = empty_string; /* equivalent of "" */
425 /* realm compare is like strcmp, but knows how to deal with these args */
426 if (realm_compare(realm_of_tgt(header_ticket),
427 header_ticket->server)) {
428 /* tgt issued by local realm */
429 enc_tkt_reply.transited = header_ticket->enc_part2->transited;
431 /* assemble new transited field into allocated storage */
432 if (header_ticket->enc_part2->transited.tr_type !=
433 KRB5_DOMAIN_X500_COMPRESS) {
434 status = "BAD_TRTYPE";
435 errcode = KRB5KDC_ERR_TRTYPE_NOSUPP;
438 enc_tkt_transited.tr_type = KRB5_DOMAIN_X500_COMPRESS;
439 enc_tkt_transited.tr_contents.data = 0;
440 enc_tkt_transited.tr_contents.length = 0;
441 enc_tkt_reply.transited = enc_tkt_transited;
443 add_to_transited(&header_ticket->enc_part2->transited.tr_contents,
444 &enc_tkt_reply.transited.tr_contents,
445 header_ticket->server,
446 enc_tkt_reply.client,
448 status = "ADD_TR_FAIL";
454 ticket_reply.enc_part2 = &enc_tkt_reply;
456 if (isflagset(request->kdc_options, KDC_OPT_ENC_TKT_IN_SKEY)) {
457 krb5_keyblock *st_sealing_key;
458 krb5_kvno st_srv_kvno;
460 if (retval = kdc_get_server_key(request->second_ticket[st_idx],
463 status = "2ND_TKT_SERVER";
467 /* decrypt the ticket */
468 retval = krb5_decrypt_tkt_part(st_sealing_key,
469 request->second_ticket[st_idx]);
470 krb5_free_keyblock(st_sealing_key);
472 status = "2ND_TKT_DECRYPT";
477 * Make sure the client for the second ticket matches
480 if (!krb5_principal_compare(request->server,
481 request->second_ticket[st_idx]->enc_part2->client)) {
482 if (retval = krb5_unparse_name(request->second_ticket[st_idx]->enc_part2->client, &tmp))
484 syslog(LOG_INFO, "TGS_REQ: 2ND_TKT_MISMATCH: authtime %d, host %s, %s for %s, 2nd tkt client %s",
485 authtime, fromstring, cname, sname,
486 tmp ? tmp : "<unknown>");
490 if (retval = krb5_encrypt_tkt_part(request->second_ticket[st_idx]->enc_part2->session,
492 status = "2ND_TKT_ENCRYPT";
497 /* convert server.key into a real key (it may be encrypted
499 if (retval = KDB_CONVERT_KEY_OUTOF_DB(&server.key, &encrypting_key)) {
504 retval = krb5_encrypt_tkt_part(&encrypting_key, &ticket_reply);
506 memset((char *)encrypting_key.contents, 0, encrypting_key.length);
507 krb5_xfree(encrypting_key.contents);
510 status = "TKT_ENCRYPT";
515 /* Start assembling the response */
516 reply.msg_type = KRB5_TGS_REP;
517 reply.padata = 0; /* always */
518 reply.client = header_ticket->enc_part2->client;
519 reply.enc_part.etype = useetype;
520 reply.enc_part.kvno = 0; /* We are using the session key */
521 reply.ticket = &ticket_reply;
523 reply_encpart.session = session_key;
524 reply_encpart.nonce = request->nonce;
526 /* copy the time fields EXCEPT for authtime; its location
528 reply_encpart.times = enc_tkt_reply.times;
529 reply_encpart.times.authtime = header_ticket->enc_part2->times.authtime;
531 /* starttime is optional, and treated as authtime if not present.
532 so we can nuke it if it matches */
533 if (enc_tkt_reply.times.starttime == enc_tkt_reply.times.authtime)
534 enc_tkt_reply.times.starttime = 0;
536 nolrentry.lr_type = KRB5_LRQ_NONE;
538 nolrarray[0] = &nolrentry;
540 reply_encpart.last_req = nolrarray; /* not available for TGS reqs */
541 reply_encpart.key_exp = 0; /* ditto */
542 reply_encpart.flags = enc_tkt_reply.flags;
543 reply_encpart.server = ticket_reply.server;
545 /* use the session key in the ticket, unless there's a subsession key
548 retval = krb5_encode_kdc_rep(KRB5_TGS_REP, &reply_encpart,
549 req_authdat->authenticator->subkey ?
550 req_authdat->authenticator->subkey :
551 header_ticket->enc_part2->session,
554 status = "ENCODE_KDC_REP";
559 memset(ticket_reply.enc_part.ciphertext.data, 0,
560 ticket_reply.enc_part.ciphertext.length);
561 free(ticket_reply.enc_part.ciphertext.data);
562 /* these parts are left on as a courtesy from krb5_encode_kdc_rep so we
563 can use them in raw form if needed. But, we don't... */
564 memset(reply.enc_part.ciphertext.data, 0,
565 reply.enc_part.ciphertext.length);
566 free(reply.enc_part.ciphertext.data);
570 syslog(LOG_INFO, "TGS_REQ%c %s: authtime %d, host %s, %s for %s%s%s",
571 secondary_ch, status, authtime, fromstring,
572 cname ? cname : "<unknown client>",
573 sname ? sname : "<unknown server>",
575 errcode ? error_message(errcode) : "");
577 errcode -= ERROR_TABLE_BASE_krb5;
578 if (errcode < 0 || errcode > 128)
579 errcode = KRB_ERR_GENERIC;
581 retval = prepare_error_tgs(request, header_ticket, errcode,
582 fromstring, response);
586 krb5_free_kdc_req(request);
588 krb5_free_tkt_authent(req_authdat);
594 krb5_db_free_principal(&server, 1);
596 krb5_free_keyblock(session_key);
598 free(enc_tkt_reply.transited.tr_contents.data);
603 static krb5_error_code
604 prepare_error_tgs (request, ticket, error, ident, response)
605 register krb5_kdc_req *request;
609 krb5_data **response;
612 krb5_error_code retval;
615 errpkt.ctime = request->nonce;
618 if (retval = krb5_us_timeofday(&errpkt.stime, &errpkt.susec)) {
620 krb5_free_ticket(ticket);
623 errpkt.error = error;
624 errpkt.server = request->server;
625 if (ticket && ticket->enc_part2)
626 errpkt.client = ticket->enc_part2->client;
629 errpkt.text.length = strlen(error_message(error+KRB5KDC_ERR_NONE))+1;
630 if (!(errpkt.text.data = malloc(errpkt.text.length))) {
632 krb5_free_ticket(ticket);
635 (void) strcpy(errpkt.text.data, error_message(error+KRB5KDC_ERR_NONE));
637 if (!(scratch = (krb5_data *)malloc(sizeof(*scratch)))) {
638 free(errpkt.text.data);
640 krb5_free_ticket(ticket);
643 errpkt.e_data.length = 0;
644 errpkt.e_data.data = 0;
646 retval = krb5_mk_error(&errpkt, scratch);
647 free(errpkt.text.data);
650 krb5_free_ticket(ticket);
655 * The request seems to be for a ticket-granting service somewhere else,
656 * but we don't have a ticket for the final TGS. Try to give the requestor
657 * some intermediate realm.
660 find_alternate_tgs(request, server, more, nprincs)
661 krb5_kdc_req *request;
662 krb5_db_entry *server;
666 krb5_error_code retval;
667 krb5_principal *plist, *pl2;
673 if (retval = krb5_walk_realm_tree(krb5_princ_realm(request->server),
674 krb5_princ_component(request->server, 1),
675 &plist, KRB5_REALM_BRANCH_CHAR))
678 /* move to the end */
679 for (pl2 = plist; *pl2; pl2++);
681 /* the first entry in this array is for krbtgt/local@local, so we
683 while (--pl2 > plist) {
685 tmp = *krb5_princ_realm(*pl2);
686 krb5_princ_set_realm(*pl2, krb5_princ_realm(tgs_server));
687 retval = krb5_db_get_principal(*pl2, server, nprincs, more);
688 krb5_princ_set_realm(*pl2, &tmp);
692 krb5_free_realm_tree(plist);
696 krb5_db_free_principal(server, *nprincs);
698 } else if (*nprincs == 1) {
700 krb5_principal tmpprinc;
703 tmp = *krb5_princ_realm(*pl2);
704 krb5_princ_set_realm(*pl2, krb5_princ_realm(tgs_server));
705 if (retval = krb5_copy_principal(*pl2, &tmpprinc)) {
706 krb5_db_free_principal(server, *nprincs);
707 krb5_princ_set_realm(*pl2, &tmp);
710 krb5_princ_set_realm(*pl2, &tmp);
712 krb5_free_principal(request->server);
713 request->server = tmpprinc;
714 if (krb5_unparse_name(request->server, &sname)) {
716 "TGS_REQ: issuing alternate <un-unparseable> TGT");
719 "TGS_REQ: issuing TGT %s", sname);
724 krb5_db_free_principal(server, *nprincs);
730 krb5_free_realm_tree(plist);