2 Unix SMB/CIFS implementation.
4 PAC Glue between Samba and the KDC
6 Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005-2009
7 Copyright (C) Simo Sorce <idra@samba.org> 2010
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 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, see <http://www.gnu.org/licenses/>.
25 #include "kdc/kdc-glue.h"
26 #include "kdc/pac-glue.h"
29 * Given the right private pointer from hdb_samba4,
30 * get a PAC from the attached ldb messages.
32 * For PKINIT we also get pk_reply_key and can add PAC_CREDENTIAL_INFO.
34 static krb5_error_code samba_wdc_get_pac(void *priv, krb5_context context,
35 struct hdb_entry_ex *client,
36 const krb5_keyblock *pk_reply_key,
40 DATA_BLOB *logon_blob = NULL;
41 DATA_BLOB *cred_ndr = NULL;
42 DATA_BLOB **cred_ndr_ptr = NULL;
43 DATA_BLOB _cred_blob = data_blob_null;
44 DATA_BLOB *cred_blob = NULL;
45 DATA_BLOB *upn_blob = NULL;
48 struct samba_kdc_entry *skdc_entry =
49 talloc_get_type_abort(client->ctx,
50 struct samba_kdc_entry);
52 mem_ctx = talloc_named(client->ctx, 0, "samba_get_pac context");
57 if (pk_reply_key != NULL) {
58 cred_ndr_ptr = &cred_ndr;
61 nt_status = samba_kdc_get_pac_blobs(mem_ctx, skdc_entry,
65 if (!NT_STATUS_IS_OK(nt_status)) {
70 if (pk_reply_key != NULL && cred_ndr != NULL) {
71 ret = samba_kdc_encrypt_pac_credentials(context,
80 cred_blob = &_cred_blob;
83 ret = samba_make_krb5_pac(context, logon_blob, cred_blob,
90 static krb5_error_code samba_wdc_get_pac_compat(void *priv, krb5_context context,
91 struct hdb_entry_ex *client,
94 return samba_wdc_get_pac(priv, context, client, NULL, pac);
97 /* Resign (and reform, including possibly new groups) a PAC */
99 static krb5_error_code samba_wdc_reget_pac(void *priv, krb5_context context,
100 const krb5_principal client_principal,
101 const krb5_principal delegated_proxy_principal,
102 struct hdb_entry_ex *client,
103 struct hdb_entry_ex *server,
104 struct hdb_entry_ex *krbtgt,
107 struct samba_kdc_entry *p =
108 talloc_get_type_abort(server->ctx,
109 struct samba_kdc_entry);
110 struct samba_kdc_entry *krbtgt_skdc_entry =
111 talloc_get_type_abort(krbtgt->ctx,
112 struct samba_kdc_entry);
113 TALLOC_CTX *mem_ctx = talloc_named(p, 0, "samba_kdc_reget_pac context");
114 krb5_pac new_pac = NULL;
115 DATA_BLOB *pac_blob = NULL;
116 DATA_BLOB *upn_blob = NULL;
117 DATA_BLOB *deleg_blob = NULL;
120 struct PAC_SIGNATURE_DATA *pac_srv_sig;
121 struct PAC_SIGNATURE_DATA *pac_kdc_sig;
122 bool is_in_db, is_untrusted;
123 size_t num_types = 0;
124 uint32_t *types = NULL;
125 uint32_t forced_next_type = 0;
127 ssize_t logon_info_idx = -1;
128 ssize_t delegation_idx = -1;
129 ssize_t logon_name_idx = -1;
130 ssize_t upn_dns_info_idx = -1;
131 ssize_t srv_checksum_idx = -1;
132 ssize_t kdc_checksum_idx = -1;
138 /* The user account may be set not to want the PAC */
139 if (!samba_princ_needs_pac(p)) {
140 talloc_free(mem_ctx);
144 /* If the krbtgt was generated by an RODC, and we are not that
145 * RODC, then we need to regenerate the PAC - we can't trust
147 ret = samba_krbtgt_is_in_db(krbtgt_skdc_entry, &is_in_db, &is_untrusted);
149 talloc_free(mem_ctx);
154 struct samba_kdc_entry *client_skdc_entry = NULL;
156 if (client == NULL) {
157 return KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN;
160 client_skdc_entry = talloc_get_type_abort(client->ctx,
161 struct samba_kdc_entry);
163 nt_status = samba_kdc_get_pac_blobs(mem_ctx, client_skdc_entry,
164 &pac_blob, NULL, &upn_blob);
165 if (!NT_STATUS_IS_OK(nt_status)) {
166 talloc_free(mem_ctx);
170 pac_blob = talloc_zero(mem_ctx, DATA_BLOB);
172 talloc_free(mem_ctx);
176 pac_srv_sig = talloc_zero(mem_ctx, struct PAC_SIGNATURE_DATA);
178 talloc_free(mem_ctx);
182 pac_kdc_sig = talloc_zero(mem_ctx, struct PAC_SIGNATURE_DATA);
184 talloc_free(mem_ctx);
188 nt_status = samba_kdc_update_pac_blob(mem_ctx, context,
189 krbtgt_skdc_entry, p,
191 pac_srv_sig, pac_kdc_sig);
192 if (!NT_STATUS_IS_OK(nt_status)) {
193 DEBUG(0, ("Building PAC failed: %s\n",
194 nt_errstr(nt_status)));
195 talloc_free(mem_ctx);
200 /* Now check the KDC signature, fetching the correct key based on the enc type */
201 ret = kdc_check_pac(context, pac_srv_sig->signature, pac_kdc_sig, krbtgt);
203 DEBUG(1, ("PAC KDC signature failed to verify\n"));
204 talloc_free(mem_ctx);
210 if (delegated_proxy_principal) {
211 deleg_blob = talloc_zero(mem_ctx, DATA_BLOB);
213 talloc_free(mem_ctx);
217 nt_status = samba_kdc_update_delegation_info_blob(mem_ctx,
219 server->entry.principal,
220 delegated_proxy_principal,
222 if (!NT_STATUS_IS_OK(nt_status)) {
223 DEBUG(0, ("Building PAC failed: %s\n",
224 nt_errstr(nt_status)));
225 talloc_free(mem_ctx);
230 /* Check the types of the given PAC */
231 ret = krb5_pac_get_types(context, *pac, &num_types, &types);
233 talloc_free(mem_ctx);
237 for (i = 0; i < num_types; i++) {
239 case PAC_TYPE_LOGON_INFO:
240 if (logon_info_idx != -1) {
241 DEBUG(1, ("logon type[%d] twice [%d] and [%d]: \n",
246 talloc_free(mem_ctx);
251 case PAC_TYPE_CONSTRAINED_DELEGATION:
252 if (delegation_idx != -1) {
253 DEBUG(1, ("logon type[%d] twice [%d] and [%d]: \n",
258 talloc_free(mem_ctx);
263 case PAC_TYPE_LOGON_NAME:
264 if (logon_name_idx != -1) {
265 DEBUG(1, ("logon type[%d] twice [%d] and [%d]: \n",
270 talloc_free(mem_ctx);
275 case PAC_TYPE_UPN_DNS_INFO:
276 if (upn_dns_info_idx != -1) {
277 DEBUG(1, ("logon type[%d] twice [%d] and [%d]: \n",
282 talloc_free(mem_ctx);
285 upn_dns_info_idx = i;
287 case PAC_TYPE_SRV_CHECKSUM:
288 if (srv_checksum_idx != -1) {
289 DEBUG(1, ("logon type[%d] twice [%d] and [%d]: \n",
294 talloc_free(mem_ctx);
297 srv_checksum_idx = i;
299 case PAC_TYPE_KDC_CHECKSUM:
300 if (kdc_checksum_idx != -1) {
301 DEBUG(1, ("logon type[%d] twice [%d] and [%d]: \n",
306 talloc_free(mem_ctx);
309 kdc_checksum_idx = i;
316 if (logon_info_idx == -1) {
317 DEBUG(1, ("PAC_TYPE_LOGON_INFO missing\n"));
319 talloc_free(mem_ctx);
322 if (logon_name_idx == -1) {
323 DEBUG(1, ("PAC_TYPE_LOGON_NAME missing\n"));
325 talloc_free(mem_ctx);
328 if (srv_checksum_idx == -1) {
329 DEBUG(1, ("PAC_TYPE_SRV_CHECKSUM missing\n"));
331 talloc_free(mem_ctx);
334 if (kdc_checksum_idx == -1) {
335 DEBUG(1, ("PAC_TYPE_KDC_CHECKSUM missing\n"));
337 talloc_free(mem_ctx);
341 /* Build an updated PAC */
342 ret = krb5_pac_init(context, &new_pac);
345 talloc_free(mem_ctx);
350 const uint8_t zero_byte = 0;
352 DATA_BLOB type_blob = data_blob_null;
355 if (forced_next_type != 0) {
357 * We need to inject possible missing types
359 type = forced_next_type;
360 forced_next_type = 0;
361 } else if (i < num_types) {
369 case PAC_TYPE_LOGON_INFO:
370 type_blob = *pac_blob;
372 if (delegation_idx == -1 && deleg_blob != NULL) {
373 /* inject CONSTRAINED_DELEGATION behind */
374 forced_next_type = PAC_TYPE_CONSTRAINED_DELEGATION;
377 case PAC_TYPE_CONSTRAINED_DELEGATION:
378 if (deleg_blob != NULL) {
379 type_blob = *deleg_blob;
382 case PAC_TYPE_CREDENTIAL_INFO:
384 * Note that we copy the credential blob,
385 * as it's only usable with the PKINIT based
386 * AS-REP reply key, it's only available on the
387 * host which did the AS-REQ/AS-REP exchange.
389 * This matches Windows 2008R2...
392 case PAC_TYPE_LOGON_NAME:
394 * this is generated in the main KDC code
395 * we just add a place holder here.
397 type_blob = data_blob_const(&zero_byte, 1);
399 if (upn_dns_info_idx == -1 && upn_blob != NULL) {
400 /* inject UPN_DNS_INFO behind */
401 forced_next_type = PAC_TYPE_UPN_DNS_INFO;
404 case PAC_TYPE_UPN_DNS_INFO:
406 * Replace in the RODC case, otherwise
407 * upn_blob is NULL and we just copy.
409 if (upn_blob != NULL) {
410 type_blob = *upn_blob;
413 case PAC_TYPE_SRV_CHECKSUM:
415 * this are generated in the main KDC code
416 * we just add a place holder here.
418 type_blob = data_blob_const(&zero_byte, 1);
420 case PAC_TYPE_KDC_CHECKSUM:
422 * this are generated in the main KDC code
423 * we just add a place holders here.
425 type_blob = data_blob_const(&zero_byte, 1);
432 if (type_blob.length != 0) {
433 ret = smb_krb5_copy_data_contents(&type_data,
438 krb5_pac_free(context, new_pac);
439 talloc_free(mem_ctx);
443 ret = krb5_pac_get_buffer(context, *pac,
447 krb5_pac_free(context, new_pac);
448 talloc_free(mem_ctx);
453 ret = krb5_pac_add_buffer(context, new_pac,
455 smb_krb5_free_data_contents(context, &type_data);
458 krb5_pac_free(context, new_pac);
459 talloc_free(mem_ctx);
466 /* We now replace the pac */
467 krb5_pac_free(context, *pac);
470 talloc_free(mem_ctx);
474 static char *get_netbios_name(TALLOC_CTX *mem_ctx, HostAddresses *addrs)
476 char *nb_name = NULL;
480 for (i = 0; addrs && i < addrs->len; i++) {
481 if (addrs->val[i].addr_type != KRB5_ADDRESS_NETBIOS) {
484 len = MIN(addrs->val[i].address.length, 15);
485 nb_name = talloc_strndup(mem_ctx,
486 addrs->val[i].address.data, len);
492 if ((nb_name == NULL) || (nb_name[0] == '\0')) {
496 /* Strip space padding */
497 for (len = strlen(nb_name) - 1;
498 (len > 0) && (nb_name[len] == ' ');
506 static krb5_data fill_krb5_data(void *data, size_t length)
511 kdata.length = length;
516 /* this function allocates 'data' using malloc.
517 * The caller is responsible for freeing it */
518 static void samba_kdc_build_edata_reply(NTSTATUS nt_status, DATA_BLOB *e_data)
520 krb5_error_code ret = 0;
531 pa.padata_type = KRB5_PADATA_PW_SALT;
532 pa.padata_value.length = 12;
533 pa.padata_value.data = malloc(pa.padata_value.length);
534 if (!pa.padata_value.data) {
540 SIVAL(pa.padata_value.data, 0, NT_STATUS_V(nt_status));
541 SIVAL(pa.padata_value.data, 4, 0);
542 SIVAL(pa.padata_value.data, 8, 1);
544 ASN1_MALLOC_ENCODE(PA_DATA, buf, len, &pa, &len, ret);
545 free(pa.padata_value.data);
551 e_data->length = len;
557 static krb5_error_code samba_wdc_check_client_access(void *priv,
558 krb5_context context,
559 krb5_kdc_configuration *config,
560 hdb_entry_ex *client_ex, const char *client_name,
561 hdb_entry_ex *server_ex, const char *server_name,
565 struct samba_kdc_entry *kdc_entry;
566 bool password_change;
570 kdc_entry = talloc_get_type(client_ex->ctx, struct samba_kdc_entry);
571 password_change = (server_ex && server_ex->entry.flags.change_pw);
572 workstation = get_netbios_name((TALLOC_CTX *)client_ex->ctx,
573 req->req_body.addresses);
575 nt_status = samba_kdc_check_client_access(kdc_entry,
580 if (!NT_STATUS_IS_OK(nt_status)) {
581 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_NO_MEMORY)) {
588 samba_kdc_build_edata_reply(nt_status, &data);
589 *e_data = fill_krb5_data(data.data, data.length);
592 return samba_kdc_map_policy_err(nt_status);
595 /* Now do the standard Heimdal check */
596 return kdc_check_flags(context, config,
597 client_ex, client_name,
598 server_ex, server_name,
599 req->msg_type == krb_as_req);
602 static krb5_error_code samba_wdc_plugin_init(krb5_context context, void **ptr)
608 static void samba_wdc_plugin_fini(void *ptr)
613 struct krb5plugin_windc_ftable windc_plugin_table = {
614 .minor_version = KRB5_WINDC_PLUGIN_MINOR,
615 .init = samba_wdc_plugin_init,
616 .fini = samba_wdc_plugin_fini,
617 .pac_generate = samba_wdc_get_pac_compat,
618 .pac_verify = samba_wdc_reget_pac,
619 .client_access = samba_wdc_check_client_access,
620 .pac_pk_generate = samba_wdc_get_pac,