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.
30 verify an incoming ticket and parse out the principal name and
31 authorization_data if available
33 NTSTATUS ads_verify_ticket(const char *realm, const DATA_BLOB *ticket,
34 char **principal, DATA_BLOB *auth_data,
36 DATA_BLOB *session_key)
38 NTSTATUS sret = NT_STATUS_LOGON_FAILURE;
39 krb5_context context = NULL;
40 krb5_auth_context auth_context = NULL;
42 krb5_ticket *tkt = NULL;
43 krb5_rcache rcache = NULL;
45 krb5_keyblock *key = NULL;
47 krb5_principal host_princ;
48 char *host_princ_s = NULL;
49 BOOL free_host_princ = False;
50 BOOL got_replay_mutex = False;
53 char *password_s = NULL;
55 krb5_enctype *enctypes = NULL;
57 krb5_address local_addr;
58 krb5_address remote_addr;
63 ZERO_STRUCT(password);
64 ZERO_STRUCTP(auth_data);
67 if (!secrets_init()) {
68 DEBUG(1,("ads_verify_ticket: secrets_init failed\n"));
69 return NT_STATUS_LOGON_FAILURE;
72 password_s = secrets_fetch_machine_password(lp_workgroup(), NULL, NULL);
74 DEBUG(1,("ads_verify_ticket: failed to fetch machine password\n"));
75 return NT_STATUS_LOGON_FAILURE;
78 password.data = password_s;
79 password.length = strlen(password_s);
81 ret = krb5_init_context(&context);
83 DEBUG(1,("ads_verify_ticket: krb5_init_context failed (%s)\n", error_message(ret)));
84 return NT_STATUS_LOGON_FAILURE;
87 ret = krb5_set_default_realm(context, realm);
89 DEBUG(1,("ads_verify_ticket: krb5_set_default_realm failed (%s)\n", error_message(ret)));
90 sret = NT_STATUS_LOGON_FAILURE;
94 /* This whole process is far more complex than I would
95 like. We have to go through all this to allow us to store
96 the secret internally, instead of using /etc/krb5.keytab */
98 ret = krb5_auth_con_init(context, &auth_context);
100 DEBUG(1,("ads_verify_ticket: krb5_auth_con_init failed (%s)\n", error_message(ret)));
101 sret = NT_STATUS_LOGON_FAILURE;
105 fstrcpy(myname, global_myname());
107 asprintf(&host_princ_s, "HOST/%s@%s", myname, lp_realm());
108 ret = krb5_parse_name(context, host_princ_s, &host_princ);
110 DEBUG(1,("ads_verify_ticket: krb5_parse_name(%s) failed (%s)\n",
111 host_princ_s, error_message(ret)));
112 sret = NT_STATUS_LOGON_FAILURE;
116 free_host_princ = True;
119 * JRA. We must set the rcache here. This will prevent replay attacks.
122 ret = krb5_get_server_rcache(context, krb5_princ_component(context, host_princ, 0), &rcache);
124 DEBUG(1,("ads_verify_ticket: krb5_get_server_rcache failed (%s)\n", error_message(ret)));
125 sret = NT_STATUS_LOGON_FAILURE;
129 ret = krb5_auth_con_setrcache(context, auth_context, rcache);
131 DEBUG(1,("ads_verify_ticket: krb5_auth_con_setrcache failed (%s)\n", error_message(ret)));
132 sret = NT_STATUS_LOGON_FAILURE;
136 /* CIFS doesn't use addresses in tickets. This would breat NAT. JRA */
138 if ((ret = get_kerberos_allowed_etypes(context, &enctypes))) {
139 DEBUG(1,("ads_verify_ticket: krb5_get_permitted_enctypes failed (%s)\n",
140 error_message(ret)));
141 sret = NT_STATUS_LOGON_FAILURE;
145 /* Lock a mutex surrounding the replay as there is no locking in the MIT krb5
146 * code surrounding the replay cache... */
148 if (!grab_server_mutex("replay cache mutex")) {
149 DEBUG(1,("ads_verify_ticket: unable to protect replay cache with mutex.\n"));
150 sret = NT_STATUS_LOGON_FAILURE;
154 got_replay_mutex = True;
156 /* We need to setup a auth context with each possible encoding type in turn. */
157 for (i=0;enctypes[i];i++) {
158 if (!(key = (krb5_keyblock *)malloc(sizeof(*key)))) {
159 sret = NT_STATUS_NO_MEMORY;
163 if (create_kerberos_key_from_string(context, host_princ, &password, key, enctypes[i])) {
167 krb5_auth_con_setuseruserkey(context, auth_context, key);
169 krb5_free_keyblock(context, key);
171 packet.length = ticket->length;
172 packet.data = (krb5_pointer)ticket->data;
174 if (!(ret = krb5_rd_req(context, &auth_context, &packet,
176 NULL, NULL, &tkt))) {
177 DEBUG(10,("ads_verify_ticket: enc type [%u] decrypted message !\n",
178 (unsigned int)enctypes[i] ));
183 DEBUG((ret != KRB5_BAD_ENCTYPE) ? 3 : 10,
184 ("ads_verify_ticket: enc type [%u] failed to decrypt with error %s\n",
185 (unsigned int)enctypes[i], error_message(ret)));
188 release_server_mutex();
189 got_replay_mutex = False;
192 DEBUG(3,("ads_verify_ticket: krb5_rd_req with auth failed (%s)\n",
193 error_message(ret)));
194 sret = NT_STATUS_LOGON_FAILURE;
198 ret = krb5_mk_rep(context, auth_context, &packet);
200 DEBUG(3,("ads_verify_ticket: Failed to generate mutual authentication reply (%s)\n",
201 error_message(ret)));
202 sret = NT_STATUS_LOGON_FAILURE;
206 *ap_rep = data_blob(packet.data, packet.length);
209 get_krb5_smb_session_key(context, auth_context, session_key, True);
210 dump_data_pw("SMB session key (from ticket)\n", session_key->data, session_key->length);
213 file_save("/tmp/ticket.dat", ticket->data, ticket->length);
216 get_auth_data_from_tkt(auth_data, tkt);
219 TALLOC_CTX *ctx = talloc_init("pac data");
220 decode_pac_data(auth_data, ctx);
225 if (tkt->enc_part2) {
226 file_save("/tmp/authdata.dat",
227 tkt->enc_part2->authorization_data[0]->contents,
228 tkt->enc_part2->authorization_data[0]->length);
232 if ((ret = krb5_unparse_name(context, get_principal_from_tkt(tkt),
234 DEBUG(3,("ads_verify_ticket: krb5_unparse_name failed (%s)\n",
235 error_message(ret)));
236 sret = NT_STATUS_LOGON_FAILURE;
244 if (got_replay_mutex)
245 release_server_mutex();
247 if (!NT_STATUS_IS_OK(sret))
248 data_blob_free(auth_data);
250 if (!NT_STATUS_IS_OK(sret))
251 data_blob_free(ap_rep);
254 krb5_free_principal(context, host_princ);
257 krb5_free_ticket(context, tkt);
258 free_kerberos_etypes(context, enctypes);
259 SAFE_FREE(password_s);
260 SAFE_FREE(host_princ_s);
263 krb5_auth_con_free(context, auth_context);
266 krb5_free_context(context);
271 #endif /* HAVE_KRB5 */