2 Unix SMB/CIFS implementation.
3 kerberos keytab utility library
4 Copyright (C) Andrew Tridgell 2001
5 Copyright (C) Remus Koos 2001
6 Copyright (C) Luke Howard 2003
7 Copyright (C) Jim McDonough (jmcd@us.ibm.com) 2003
8 Copyright (C) Guenther Deschner 2003
9 Copyright (C) Rakesh Patel 2004
10 Copyright (C) Dan Perry 2004
11 Copyright (C) Jeremy Allison 2004
12 Copyright (C) Gerald Carter 2006
14 This program is free software; you can redistribute it and/or modify
15 it under the terms of the GNU General Public License as published by
16 the Free Software Foundation; either version 3 of the License, or
17 (at your option) any later version.
19 This program is distributed in the hope that it will be useful,
20 but WITHOUT ANY WARRANTY; without even the implied warranty of
21 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 GNU General Public License for more details.
24 You should have received a copy of the GNU General Public License
25 along with this program. If not, see <http://www.gnu.org/licenses/>.
37 /* This MAX_NAME_LEN is a constant defined in krb5.h */
38 #ifndef MAX_KEYTAB_NAME_LEN
39 #define MAX_KEYTAB_NAME_LEN 1100
42 static krb5_error_code ads_keytab_open(krb5_context context,
45 char keytab_str[MAX_KEYTAB_NAME_LEN] = {0};
46 const char *keytab_name = NULL;
47 krb5_error_code ret = 0;
49 switch (lp_kerberos_method()) {
50 case KERBEROS_VERIFY_SYSTEM_KEYTAB:
51 case KERBEROS_VERIFY_SECRETS_AND_KEYTAB:
52 ret = krb5_kt_default_name(context,
54 sizeof(keytab_str) - 2);
56 DBG_WARNING("Failed to get default keytab name");
59 keytab_name = keytab_str;
61 case KERBEROS_VERIFY_DEDICATED_KEYTAB:
62 keytab_name = lp_dedicated_keytab_file();
65 DBG_ERR("Invalid kerberos method set (%d)\n",
66 lp_kerberos_method());
67 ret = KRB5_KT_BADNAME;
71 if (keytab_name == NULL || keytab_name[0] == '\0') {
72 DBG_ERR("Invalid keytab name\n");
73 ret = KRB5_KT_BADNAME;
77 ret = smb_krb5_kt_open(context, keytab_name, true, keytab);
79 DBG_WARNING("smb_krb5_kt_open failed (%s)\n",
88 static bool fill_default_spns(TALLOC_CTX *ctx, const char *machine_name,
89 const char *my_fqdn, const char *spn,
95 *spns = talloc_zero_array(ctx, const char*, 3);
101 psp1 = talloc_asprintf(ctx,
109 if (!strlower_m(&psp1[strlen(spn) + 1])) {
114 psp2 = talloc_asprintf(ctx,
122 if (!strlower_m(&psp2[strlen(spn) + 1])) {
131 static bool ads_set_machine_account_spns(TALLOC_CTX *ctx,
133 const char *service_or_spn,
136 const char **spn_names = NULL;
138 struct spn_struct* spn_struct = NULL;
141 /* SPN should have '/' */
142 tmp = strchr_m(service_or_spn, '/');
144 spn_struct = parse_spn(ctx, service_or_spn);
145 if (spn_struct == NULL) {
150 DBG_INFO("Attempting to add/update '%s'\n", service_or_spn);
152 if (spn_struct != NULL) {
153 spn_names = talloc_zero_array(ctx, const char*, 2);
154 spn_names[0] = service_or_spn;
158 ok = fill_default_spns(ctx,
167 aderr = ads_add_service_principal_names(ads,
170 if (!ADS_ERR_OK(aderr)) {
171 DBG_WARNING("Failed to add service principal name.\n");
179 * Create kerberos principal(s) from SPN or service name.
181 static bool service_or_spn_to_kerberos_princ(TALLOC_CTX *ctx,
182 const char *service_or_spn,
185 char **p_short_princ_s)
187 char *princ_s = NULL;
188 char *short_princ_s = NULL;
189 const char *service = service_or_spn;
190 const char *host = my_fqdn;
191 struct spn_struct* spn_struct = NULL;
195 /* SPN should have '/' */
196 tmp = strchr_m(service_or_spn, '/');
198 spn_struct = parse_spn(ctx, service_or_spn);
199 if (spn_struct == NULL) {
204 if (spn_struct != NULL) {
205 service = spn_struct->serviceclass;
206 host = spn_struct->host;
208 princ_s = talloc_asprintf(ctx, "%s/%s@%s",
211 if (princ_s == NULL) {
216 if (spn_struct == NULL) {
217 short_princ_s = talloc_asprintf(ctx, "%s/%s@%s",
218 service, lp_netbios_name(),
220 if (short_princ_s == NULL) {
225 *p_princ_s = princ_s;
226 *p_short_princ_s = short_princ_s;
231 /**********************************************************************
232 Adds a single service principal, i.e. 'host' to the system keytab
233 ***********************************************************************/
235 int ads_keytab_add_entry(ADS_STRUCT *ads, const char *srvPrinc, bool update_ads)
237 krb5_error_code ret = 0;
238 krb5_context context = NULL;
239 krb5_keytab keytab = NULL;
242 krb5_enctype enctypes[6] = {
245 #ifdef HAVE_ENCTYPE_AES128_CTS_HMAC_SHA1_96
246 ENCTYPE_AES128_CTS_HMAC_SHA1_96,
248 #ifdef HAVE_ENCTYPE_AES256_CTS_HMAC_SHA1_96
249 ENCTYPE_AES256_CTS_HMAC_SHA1_96,
251 ENCTYPE_ARCFOUR_HMAC,
254 char *princ_s = NULL;
255 char *short_princ_s = NULL;
256 char *salt_princ_s = NULL;
257 char *password_s = NULL;
259 TALLOC_CTX *tmpctx = NULL;
262 initialize_krb5_error_table();
263 ret = krb5_init_context(&context);
265 DEBUG(1, (__location__ ": could not krb5_init_context: %s\n",
266 error_message(ret)));
270 ret = ads_keytab_open(context, &keytab);
275 /* retrieve the password */
276 if (!secrets_init()) {
277 DEBUG(1, (__location__ ": secrets_init failed\n"));
281 password_s = secrets_fetch_machine_password(lp_workgroup(), NULL, NULL);
283 DEBUG(1, (__location__ ": failed to fetch machine password\n"));
287 ZERO_STRUCT(password);
288 password.data = password_s;
289 password.length = strlen(password_s);
291 /* we need the dNSHostName value here */
292 tmpctx = talloc_init(__location__);
294 DEBUG(0, (__location__ ": talloc_init() failed!\n"));
299 my_fqdn = ads_get_dnshostname(ads, tmpctx, lp_netbios_name());
301 DEBUG(0, (__location__ ": unable to determine machine "
302 "account's dns name in AD!\n"));
307 /* make sure we have a single instance of a the computer account */
308 if (!ads_has_samaccountname(ads, tmpctx, lp_netbios_name())) {
309 DEBUG(0, (__location__ ": unable to determine machine "
310 "account's short name in AD!\n"));
315 /* Construct our principal */
316 if (strchr_m(srvPrinc, '@')) {
317 /* It's a fully-named principal. */
318 princ_s = talloc_asprintf(tmpctx, "%s", srvPrinc);
323 } else if (srvPrinc[strlen(srvPrinc)-1] == '$') {
324 /* It's the machine account, as used by smbclient clients. */
325 princ_s = talloc_asprintf(tmpctx, "%s@%s",
326 srvPrinc, lp_realm());
332 /* It's a normal service principal. Add the SPN now so that we
333 * can obtain credentials for it and double-check the salt value
334 * used to generate the service's keys. */
336 if (!service_or_spn_to_kerberos_princ(tmpctx,
345 /* According to http://support.microsoft.com/kb/326985/en-us,
346 certain principal names are automatically mapped to the
347 host/... principal in the AD account.
348 So only create these in the keytab, not in AD. --jerry */
350 if (update_ads && !strequal(srvPrinc, "cifs") &&
351 !strequal(srvPrinc, "host")) {
352 if (!ads_set_machine_account_spns(tmpctx,
362 kvno = (krb5_kvno)ads_get_machine_kvno(ads, lp_netbios_name());
364 /* -1 indicates failure, everything else is OK */
365 DEBUG(1, (__location__ ": ads_get_machine_kvno failed to "
366 "determine the system's kvno.\n"));
371 salt_princ_s = kerberos_secrets_fetch_salt_princ();
372 if (salt_princ_s == NULL) {
373 DBG_WARNING("kerberos_secrets_fetch_salt_princ() failed\n");
378 for (i = 0; enctypes[i]; i++) {
380 /* add the fqdn principal to the keytab */
381 ret = smb_krb5_kt_add_entry(context,
391 DEBUG(1, (__location__ ": Failed to add entry to keytab\n"));
395 /* add the short principal name if we have one */
397 ret = smb_krb5_kt_add_entry(context,
407 DEBUG(1, (__location__
408 ": Failed to add short entry to keytab\n"));
415 SAFE_FREE(salt_princ_s);
419 krb5_kt_close(context, keytab);
422 krb5_free_context(context);
427 /**********************************************************************
428 Flushes all entries from the system keytab.
429 ***********************************************************************/
431 int ads_keytab_flush(ADS_STRUCT *ads)
433 krb5_error_code ret = 0;
434 krb5_context context = NULL;
435 krb5_keytab keytab = NULL;
439 initialize_krb5_error_table();
440 ret = krb5_init_context(&context);
442 DEBUG(1, (__location__ ": could not krb5_init_context: %s\n",
443 error_message(ret)));
447 ret = ads_keytab_open(context, &keytab);
452 kvno = (krb5_kvno)ads_get_machine_kvno(ads, lp_netbios_name());
454 /* -1 indicates a failure */
455 DEBUG(1, (__location__ ": Error determining the kvno.\n"));
459 /* Seek and delete old keytab entries */
460 ret = smb_krb5_kt_seek_and_delete_old_entries(context,
472 aderr = ads_clear_service_principal_names(ads, lp_netbios_name());
473 if (!ADS_ERR_OK(aderr)) {
474 DEBUG(1, (__location__ ": Error while clearing service "
475 "principal listings in LDAP.\n"));
481 krb5_kt_close(context, keytab);
484 krb5_free_context(context);
489 /**********************************************************************
490 Adds all the required service principals to the system keytab.
491 ***********************************************************************/
493 int ads_keytab_create_default(ADS_STRUCT *ads)
495 krb5_error_code ret = 0;
496 krb5_context context = NULL;
497 krb5_keytab keytab = NULL;
498 krb5_kt_cursor cursor = {0};
499 krb5_keytab_entry kt_entry = {0};
502 char *sam_account_name, *upn;
503 char **oldEntries = NULL, *princ_s[26];
512 ZERO_STRUCT(kt_entry);
515 frame = talloc_stackframe();
521 status = ads_get_service_principal_names(frame,
526 if (!ADS_ERR_OK(status)) {
531 for (i = 0; i < num_spns; i++) {
535 srv_princ = strlower_talloc(frame, spn_array[i]);
536 if (srv_princ == NULL) {
541 p = strchr_m(srv_princ, '/');
547 /* Add the SPNs found on the DC */
548 ret = ads_keytab_add_entry(ads, srv_princ, false);
550 DEBUG(1, ("ads_keytab_add_entry failed while "
551 "adding '%s' principal.\n",
557 #if 0 /* don't create the CIFS/... keytab entries since no one except smbd
558 really needs them and we will fall back to verifying against
561 ret = ads_keytab_add_entry(ads, "cifs", false));
563 DEBUG(1, (__location__ ": ads_keytab_add_entry failed while "
564 "adding 'cifs'.\n"));
569 memset(princ_s, '\0', sizeof(princ_s));
571 initialize_krb5_error_table();
572 ret = krb5_init_context(&context);
574 DEBUG(1, (__location__ ": could not krb5_init_context: %s\n",
575 error_message(ret)));
579 machine_name = talloc_strdup(frame, lp_netbios_name());
585 /* now add the userPrincipalName and sAMAccountName entries */
586 ok = ads_has_samaccountname(ads, frame, machine_name);
588 DEBUG(0, (__location__ ": unable to determine machine "
589 "account's name in AD!\n"));
595 * append '$' to netbios name so 'ads_keytab_add_entry' recognises
596 * it as a machine account rather than a service or Windows SPN.
598 sam_account_name = talloc_asprintf(frame, "%s$",machine_name);
599 if (sam_account_name == NULL) {
603 /* upper case the sAMAccountName to make it easier for apps to
604 know what case to use in the keytab file */
605 if (!strupper_m(sam_account_name)) {
610 ret = ads_keytab_add_entry(ads, sam_account_name, false);
612 DEBUG(1, (__location__ ": ads_keytab_add_entry() failed "
613 "while adding sAMAccountName (%s)\n",
618 /* remember that not every machine account will have a upn */
619 upn = ads_get_upn(ads, frame, machine_name);
621 ret = ads_keytab_add_entry(ads, upn, false);
623 DEBUG(1, (__location__ ": ads_keytab_add_entry() "
624 "failed while adding UPN (%s)\n", upn));
629 /* Now loop through the keytab and update any other existing entries */
630 kvno = (krb5_kvno)ads_get_machine_kvno(ads, machine_name);
631 if (kvno == (krb5_kvno)-1) {
632 DEBUG(1, (__location__ ": ads_get_machine_kvno() failed to "
633 "determine the system's kvno.\n"));
637 DEBUG(3, (__location__ ": Searching for keytab entries to preserve "
640 ret = ads_keytab_open(context, &keytab);
645 ret = krb5_kt_start_seq_get(context, keytab, &cursor);
646 if (ret != KRB5_KT_END && ret != ENOENT ) {
647 while ((ret = krb5_kt_next_entry(context, keytab,
648 &kt_entry, &cursor)) == 0) {
649 smb_krb5_kt_free_entry(context, &kt_entry);
650 ZERO_STRUCT(kt_entry);
654 krb5_kt_end_seq_get(context, keytab, &cursor);
658 * Hmmm. There is no "rewind" function for the keytab. This means we
659 * have a race condition where someone else could add entries after
660 * we've counted them. Re-open asap to minimise the race. JRA.
662 DEBUG(3, (__location__ ": Found %zd entries in the keytab.\n", found));
667 oldEntries = talloc_zero_array(frame, char *, found + 1);
669 DEBUG(1, (__location__ ": Failed to allocate space to store "
670 "the old keytab entries (talloc failed?).\n"));
675 ret = krb5_kt_start_seq_get(context, keytab, &cursor);
676 if (ret == KRB5_KT_END || ret == ENOENT) {
677 krb5_kt_end_seq_get(context, keytab, &cursor);
682 while (krb5_kt_next_entry(context, keytab, &kt_entry, &cursor) == 0) {
683 if (kt_entry.vno != kvno) {
684 char *ktprinc = NULL;
687 /* This returns a malloc'ed string in ktprinc. */
688 ret = smb_krb5_unparse_name(oldEntries, context,
692 DEBUG(1, (__location__
693 ": smb_krb5_unparse_name failed "
694 "(%s)\n", error_message(ret)));
698 * From looking at the krb5 source they don't seem to
699 * take locale or mb strings into account.
700 * Maybe this is because they assume utf8 ?
701 * In this case we may need to convert from utf8 to
702 * mb charset here ? JRA.
704 p = strchr_m(ktprinc, '@');
709 p = strchr_m(ktprinc, '/');
713 for (i = 0; i < found; i++) {
714 if (!oldEntries[i]) {
715 oldEntries[i] = ktprinc;
718 if (!strcmp(oldEntries[i], ktprinc)) {
719 TALLOC_FREE(ktprinc);
724 TALLOC_FREE(ktprinc);
727 smb_krb5_kt_free_entry(context, &kt_entry);
728 ZERO_STRUCT(kt_entry);
730 krb5_kt_end_seq_get(context, keytab, &cursor);
734 for (i = 0; oldEntries[i]; i++) {
735 ret |= ads_keytab_add_entry(ads, oldEntries[i], false);
736 TALLOC_FREE(oldEntries[i]);
740 TALLOC_FREE(oldEntries);
744 if (!all_zero((uint8_t *)&kt_entry, sizeof(kt_entry))) {
745 smb_krb5_kt_free_entry(context, &kt_entry);
747 if (!all_zero((uint8_t *)&cursor, sizeof(cursor)) && keytab) {
748 krb5_kt_end_seq_get(context, keytab, &cursor);
751 krb5_kt_close(context, keytab);
753 krb5_free_context(context);
758 #endif /* HAVE_ADS */
760 /**********************************************************************
762 ***********************************************************************/
764 int ads_keytab_list(const char *keytab_name)
766 krb5_error_code ret = 0;
767 krb5_context context = NULL;
768 krb5_keytab keytab = NULL;
769 krb5_kt_cursor cursor;
770 krb5_keytab_entry kt_entry;
772 ZERO_STRUCT(kt_entry);
775 initialize_krb5_error_table();
776 ret = krb5_init_context(&context);
778 DEBUG(1, (__location__ ": could not krb5_init_context: %s\n",
779 error_message(ret)));
783 if (keytab_name == NULL) {
785 ret = ads_keytab_open(context, &keytab);
790 ret = smb_krb5_kt_open(context, keytab_name, False, &keytab);
793 DEBUG(1, ("smb_krb5_kt_open failed (%s)\n",
794 error_message(ret)));
798 ret = krb5_kt_start_seq_get(context, keytab, &cursor);
804 printf("Vno Type Principal\n");
806 while (krb5_kt_next_entry(context, keytab, &kt_entry, &cursor) == 0) {
808 char *princ_s = NULL;
809 char *etype_s = NULL;
810 krb5_enctype enctype = 0;
812 ret = smb_krb5_unparse_name(talloc_tos(), context,
813 kt_entry.principal, &princ_s);
818 enctype = smb_krb5_kt_get_enctype_from_entry(&kt_entry);
820 ret = smb_krb5_enctype_to_string(context, enctype, &etype_s);
822 (asprintf(&etype_s, "UNKNOWN: %d\n", enctype) == -1)) {
823 TALLOC_FREE(princ_s);
827 printf("%3d %-43s %s\n", kt_entry.vno, etype_s, princ_s);
829 TALLOC_FREE(princ_s);
832 ret = smb_krb5_kt_free_entry(context, &kt_entry);
838 ret = krb5_kt_end_seq_get(context, keytab, &cursor);
843 /* Ensure we don't double free. */
844 ZERO_STRUCT(kt_entry);
848 if (!all_zero((uint8_t *)&kt_entry, sizeof(kt_entry))) {
849 smb_krb5_kt_free_entry(context, &kt_entry);
851 if (!all_zero((uint8_t *)&cursor, sizeof(cursor)) && keytab) {
852 krb5_kt_end_seq_get(context, keytab, &cursor);
856 krb5_kt_close(context, keytab);
859 krb5_free_context(context);
864 #endif /* HAVE_KRB5 */