2 Unix SMB/CIFS implementation.
3 kerberos utility library
4 Copyright (C) Andrew Tridgell 2001
5 Copyright (C) Remus Koos 2001
6 Copyright (C) Luke Howard 2003
7 Copyright (C) Guenther Deschner 2003
8 Copyright (C) Jim McDonough (jmcd@us.ibm.com) 2003
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 2 of the License, or
13 (at your option) any later version.
15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with this program; if not, write to the Free Software
22 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
29 #if !defined(HAVE_KRB5_PRINC_COMPONENT)
30 const krb5_data *krb5_princ_component(krb5_context, krb5_principal, int );
33 /**********************************************************************************
34 Try to verify a ticket using the system keytab... the system keytab has kvno -1 entries, so
35 it's more like what microsoft does... see comment in utils/net_ads.c in the
36 ads_keytab_add_entry function for details.
37 ***********************************************************************************/
39 static BOOL ads_keytab_verify_ticket(krb5_context context, krb5_auth_context auth_context,
40 const DATA_BLOB *ticket, krb5_data *p_packet, krb5_ticket **pp_tkt)
42 krb5_error_code ret = 0;
45 krb5_keytab keytab = NULL;
46 krb5_kt_cursor cursor;
47 krb5_keytab_entry kt_entry;
48 char *princ_name = NULL;
50 ZERO_STRUCT(kt_entry);
53 ret = krb5_kt_default(context, &keytab);
55 DEBUG(1, ("ads_keytab_verify_ticket: krb5_kt_default failed (%s)\n", error_message(ret)));
59 ret = krb5_kt_start_seq_get(context, keytab, &cursor);
61 DEBUG(1, ("ads_keytab_verify_ticket: krb5_kt_start_seq_get failed (%s)\n", error_message(ret)));
65 while (!krb5_kt_next_entry(context, keytab, &kt_entry, &cursor)) {
66 ret = krb5_unparse_name(context, kt_entry.principal, &princ_name);
68 DEBUG(1, ("ads_keytab_verify_ticket: krb5_unparse_name failed (%s)\n", error_message(ret)));
71 /* Look for a CIFS ticket */
72 if (!StrnCaseCmp(princ_name, "cifs/", 5)) {
73 #ifdef HAVE_KRB5_KEYTAB_ENTRY_KEYBLOCK
74 krb5_auth_con_setuseruserkey(context, auth_context, &kt_entry.keyblock);
76 krb5_auth_con_setuseruserkey(context, auth_context, &kt_entry.key);
79 p_packet->length = ticket->length;
80 p_packet->data = (krb5_pointer)ticket->data;
82 if (!(ret = krb5_rd_req(context, &auth_context, p_packet, NULL, NULL, NULL, pp_tkt))) {
84 krb5_free_unparsed_name(context, princ_name);
86 #ifdef HAVE_KRB5_KEYTAB_ENTRY_KEYBLOCK
87 keytype = (unsigned int) kt_entry.keyblock.keytype;
89 keytype = (unsigned int) kt_entry.key.enctype;
91 DEBUG(10,("ads_keytab_verify_ticket: enc type [%u] decrypted message !\n",
97 krb5_free_unparsed_name(context, princ_name);
100 if (ret && ret != KRB5_KT_END) {
101 /* This failed because something went wrong, not because the keytab file was empty. */
102 DEBUG(1, ("ads_keytab_verify_ticket: krb5_kt_next_entry failed (%s)\n", error_message(ret)));
109 krb5_free_unparsed_name(context, princ_name);
112 krb5_kt_cursor zero_csr;
113 ZERO_STRUCT(zero_csr);
114 if ((memcmp(&cursor, &zero_csr, sizeof(krb5_kt_cursor)) != 0) && keytab) {
115 krb5_kt_end_seq_get(context, keytab, &cursor);
119 krb5_kt_close(context, keytab);
125 /**********************************************************************************
126 Try to verify a ticket using the secrets.tdb.
127 ***********************************************************************************/
129 static BOOL ads_secrets_verify_ticket(krb5_context context, krb5_auth_context auth_context,
130 krb5_principal host_princ,
131 const DATA_BLOB *ticket, krb5_data *p_packet, krb5_ticket **pp_tkt)
133 krb5_error_code ret = 0;
134 BOOL auth_ok = False;
135 char *password_s = NULL;
137 krb5_enctype *enctypes = NULL;
140 if (!secrets_init()) {
141 DEBUG(1,("ads_secrets_verify_ticket: secrets_init failed\n"));
145 password_s = secrets_fetch_machine_password(lp_workgroup(), NULL, NULL);
147 DEBUG(1,("ads_secrets_verify_ticket: failed to fetch machine password\n"));
151 password.data = password_s;
152 password.length = strlen(password_s);
154 /* CIFS doesn't use addresses in tickets. This would break NAT. JRA */
156 if ((ret = get_kerberos_allowed_etypes(context, &enctypes))) {
157 DEBUG(1,("ads_secrets_verify_ticket: krb5_get_permitted_enctypes failed (%s)\n",
158 error_message(ret)));
162 p_packet->length = ticket->length;
163 p_packet->data = (krb5_pointer)ticket->data;
165 /* We need to setup a auth context with each possible encoding type in turn. */
166 for (i=0;enctypes[i];i++) {
167 krb5_keyblock *key = NULL;
169 if (!(key = (krb5_keyblock *)malloc(sizeof(*key)))) {
173 if (create_kerberos_key_from_string(context, host_princ, &password, key, enctypes[i])) {
178 krb5_auth_con_setuseruserkey(context, auth_context, key);
180 krb5_free_keyblock(context, key);
182 if (!(ret = krb5_rd_req(context, &auth_context, p_packet,
184 NULL, NULL, pp_tkt))) {
185 DEBUG(10,("ads_secrets_verify_ticket: enc type [%u] decrypted message !\n",
186 (unsigned int)enctypes[i] ));
191 DEBUG((ret != KRB5_BAD_ENCTYPE) ? 3 : 10,
192 ("ads_secrets_verify_ticket: enc type [%u] failed to decrypt with error %s\n",
193 (unsigned int)enctypes[i], error_message(ret)));
198 free_kerberos_etypes(context, enctypes);
199 SAFE_FREE(password_s);
204 /**********************************************************************************
205 Verify an incoming ticket and parse out the principal name and
206 authorization_data if available.
207 ***********************************************************************************/
209 NTSTATUS ads_verify_ticket(const char *realm, const DATA_BLOB *ticket,
210 char **principal, DATA_BLOB *auth_data,
212 DATA_BLOB *session_key)
214 NTSTATUS sret = NT_STATUS_LOGON_FAILURE;
215 krb5_context context = NULL;
216 krb5_auth_context auth_context = NULL;
218 krb5_ticket *tkt = NULL;
219 krb5_rcache rcache = NULL;
222 krb5_principal host_princ = NULL;
223 char *host_princ_s = NULL;
224 BOOL got_replay_mutex = False;
227 BOOL auth_ok = False;
230 ZERO_STRUCTP(auth_data);
231 ZERO_STRUCTP(ap_rep);
232 ZERO_STRUCTP(session_key);
234 initialize_krb5_error_table();
235 ret = krb5_init_context(&context);
237 DEBUG(1,("ads_verify_ticket: krb5_init_context failed (%s)\n", error_message(ret)));
238 return NT_STATUS_LOGON_FAILURE;
241 ret = krb5_set_default_realm(context, realm);
243 DEBUG(1,("ads_verify_ticket: krb5_set_default_realm failed (%s)\n", error_message(ret)));
247 /* This whole process is far more complex than I would
248 like. We have to go through all this to allow us to store
249 the secret internally, instead of using /etc/krb5.keytab */
251 ret = krb5_auth_con_init(context, &auth_context);
253 DEBUG(1,("ads_verify_ticket: krb5_auth_con_init failed (%s)\n", error_message(ret)));
257 name_to_fqdn(myname, global_myname());
259 asprintf(&host_princ_s, "host/%s@%s", myname, lp_realm());
260 ret = krb5_parse_name(context, host_princ_s, &host_princ);
262 DEBUG(1,("ads_verify_ticket: krb5_parse_name(%s) failed (%s)\n",
263 host_princ_s, error_message(ret)));
268 /* Lock a mutex surrounding the replay as there is no locking in the MIT krb5
269 * code surrounding the replay cache... */
271 if (!grab_server_mutex("replay cache mutex")) {
272 DEBUG(1,("ads_verify_ticket: unable to protect replay cache with mutex.\n"));
276 got_replay_mutex = True;
279 * JRA. We must set the rcache here. This will prevent replay attacks.
282 ret = krb5_get_server_rcache(context, krb5_princ_component(context, host_princ, 0), &rcache);
284 DEBUG(1,("ads_verify_ticket: krb5_get_server_rcache failed (%s)\n", error_message(ret)));
288 ret = krb5_auth_con_setrcache(context, auth_context, rcache);
290 DEBUG(1,("ads_verify_ticket: krb5_auth_con_setrcache failed (%s)\n", error_message(ret)));
294 if (lp_use_kerberos_keytab()) {
295 auth_ok = ads_keytab_verify_ticket(context, auth_context, ticket, &packet, &tkt);
298 auth_ok = ads_secrets_verify_ticket(context, auth_context, host_princ,
299 ticket, &packet, &tkt);
302 release_server_mutex();
303 got_replay_mutex = False;
306 DEBUG(3,("ads_verify_ticket: krb5_rd_req with auth failed (%s)\n",
307 error_message(ret)));
311 ret = krb5_mk_rep(context, auth_context, &packet);
313 DEBUG(3,("ads_verify_ticket: Failed to generate mutual authentication reply (%s)\n",
314 error_message(ret)));
318 *ap_rep = data_blob(packet.data, packet.length);
319 SAFE_FREE(packet.data);
322 get_krb5_smb_session_key(context, auth_context, session_key, True);
323 dump_data_pw("SMB session key (from ticket)\n", session_key->data, session_key->length);
326 file_save("/tmp/ticket.dat", ticket->data, ticket->length);
329 get_auth_data_from_tkt(auth_data, tkt);
332 TALLOC_CTX *ctx = talloc_init("pac data");
333 decode_pac_data(auth_data, ctx);
338 if (tkt->enc_part2) {
339 file_save("/tmp/authdata.dat",
340 tkt->enc_part2->authorization_data[0]->contents,
341 tkt->enc_part2->authorization_data[0]->length);
345 if ((ret = krb5_unparse_name(context, get_principal_from_tkt(tkt),
347 DEBUG(3,("ads_verify_ticket: krb5_unparse_name failed (%s)\n",
348 error_message(ret)));
349 sret = NT_STATUS_LOGON_FAILURE;
357 if (got_replay_mutex) {
358 release_server_mutex();
361 if (!NT_STATUS_IS_OK(sret)) {
362 data_blob_free(auth_data);
365 if (!NT_STATUS_IS_OK(sret)) {
366 data_blob_free(ap_rep);
370 krb5_free_principal(context, host_princ);
374 krb5_free_ticket(context, tkt);
377 SAFE_FREE(host_princ_s);
380 krb5_auth_con_free(context, auth_context);
384 krb5_free_context(context);
390 #endif /* HAVE_KRB5 */