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 static int add_kt_entry_etypes(krb5_context context
, TALLOC_CTX
*tmpctx
,
232 ADS_STRUCT
*ads
, const char *salt_princ_s
,
233 krb5_keytab keytab
, krb5_kvno kvno
,
234 const char *srvPrinc
, const char *my_fqdn
,
235 krb5_data
*password
, bool update_ads
)
237 krb5_error_code ret
= 0;
238 char *princ_s
= NULL
;
239 char *short_princ_s
= NULL
;
240 krb5_enctype enctypes
[4] = {
241 #ifdef HAVE_ENCTYPE_AES256_CTS_HMAC_SHA1_96
242 ENCTYPE_AES256_CTS_HMAC_SHA1_96
,
244 #ifdef HAVE_ENCTYPE_AES128_CTS_HMAC_SHA1_96
245 ENCTYPE_AES128_CTS_HMAC_SHA1_96
,
247 ENCTYPE_ARCFOUR_HMAC
,
252 /* Construct our principal */
253 if (strchr_m(srvPrinc
, '@')) {
254 /* It's a fully-named principal. */
255 princ_s
= talloc_asprintf(tmpctx
, "%s", srvPrinc
);
260 } else if (srvPrinc
[strlen(srvPrinc
)-1] == '$') {
261 /* It's the machine account, as used by smbclient clients. */
262 princ_s
= talloc_asprintf(tmpctx
, "%s@%s",
263 srvPrinc
, lp_realm());
269 /* It's a normal service principal. Add the SPN now so that we
270 * can obtain credentials for it and double-check the salt value
271 * used to generate the service's keys. */
273 if (!service_or_spn_to_kerberos_princ(tmpctx
,
282 /* According to http://support.microsoft.com/kb/326985/en-us,
283 certain principal names are automatically mapped to the
284 host/... principal in the AD account.
285 So only create these in the keytab, not in AD. --jerry */
287 if (update_ads
&& !strequal(srvPrinc
, "cifs") &&
288 !strequal(srvPrinc
, "host")) {
289 if (!ads_set_machine_account_spns(tmpctx
,
299 for (i
= 0; enctypes
[i
]; i
++) {
301 /* add the fqdn principal to the keytab */
302 ret
= smb_krb5_kt_add_entry(context
,
312 DBG_WARNING("Failed to add entry to keytab\n");
316 /* add the short principal name if we have one */
318 ret
= smb_krb5_kt_add_entry(context
,
328 DBG_WARNING("Failed to add short entry to keytab\n");
337 /**********************************************************************
338 Adds a single service principal, i.e. 'host' to the system keytab
339 ***********************************************************************/
341 int ads_keytab_add_entry(ADS_STRUCT
*ads
, const char *srvPrinc
, bool update_ads
)
343 krb5_error_code ret
= 0;
344 krb5_context context
= NULL
;
345 krb5_keytab keytab
= NULL
;
348 char *salt_princ_s
= NULL
;
349 char *password_s
= NULL
;
351 TALLOC_CTX
*tmpctx
= NULL
;
352 char **hostnames_array
= NULL
;
353 size_t num_hostnames
= 0;
355 ret
= smb_krb5_init_context_common(&context
);
357 DBG_ERR("kerberos init context failed (%s)\n",
362 ret
= ads_keytab_open(context
, &keytab
);
367 /* retrieve the password */
368 if (!secrets_init()) {
369 DBG_WARNING("secrets_init failed\n");
373 password_s
= secrets_fetch_machine_password(lp_workgroup(), NULL
, NULL
);
375 DBG_WARNING("failed to fetch machine password\n");
379 ZERO_STRUCT(password
);
380 password
.data
= password_s
;
381 password
.length
= strlen(password_s
);
383 /* we need the dNSHostName value here */
384 tmpctx
= talloc_init(__location__
);
386 DBG_ERR("talloc_init() failed!\n");
391 my_fqdn
= ads_get_dnshostname(ads
, tmpctx
, lp_netbios_name());
393 DBG_ERR("unable to determine machine account's dns name in "
399 /* make sure we have a single instance of a the computer account */
400 if (!ads_has_samaccountname(ads
, tmpctx
, lp_netbios_name())) {
401 DBG_ERR("unable to determine machine account's short name in "
407 kvno
= (krb5_kvno
)ads_get_machine_kvno(ads
, lp_netbios_name());
409 /* -1 indicates failure, everything else is OK */
410 DBG_WARNING("ads_get_machine_kvno failed to determine the "
416 salt_princ_s
= kerberos_secrets_fetch_salt_princ();
417 if (salt_princ_s
== NULL
) {
418 DBG_WARNING("kerberos_secrets_fetch_salt_princ() failed\n");
423 ret
= add_kt_entry_etypes(context
, tmpctx
, ads
, salt_princ_s
, keytab
,
424 kvno
, srvPrinc
, my_fqdn
, &password
,
430 if (ADS_ERR_OK(ads_get_additional_dns_hostnames(tmpctx
, ads
,
436 for (i
= 0; i
< num_hostnames
; i
++) {
438 ret
= add_kt_entry_etypes(context
, tmpctx
, ads
,
439 salt_princ_s
, keytab
,
442 &password
, update_ads
);
450 SAFE_FREE(salt_princ_s
);
454 krb5_kt_close(context
, keytab
);
457 krb5_free_context(context
);
462 /**********************************************************************
463 Flushes all entries from the system keytab.
464 ***********************************************************************/
466 int ads_keytab_flush(ADS_STRUCT
*ads
)
468 krb5_error_code ret
= 0;
469 krb5_context context
= NULL
;
470 krb5_keytab keytab
= NULL
;
474 ret
= smb_krb5_init_context_common(&context
);
476 DBG_ERR("kerberos init context failed (%s)\n",
481 ret
= ads_keytab_open(context
, &keytab
);
486 kvno
= (krb5_kvno
)ads_get_machine_kvno(ads
, lp_netbios_name());
488 /* -1 indicates a failure */
489 DEBUG(1, (__location__
": Error determining the kvno.\n"));
494 /* Seek and delete old keytab entries */
495 ret
= smb_krb5_kt_seek_and_delete_old_entries(context
,
507 aderr
= ads_clear_service_principal_names(ads
, lp_netbios_name());
508 if (!ADS_ERR_OK(aderr
)) {
509 DEBUG(1, (__location__
": Error while clearing service "
510 "principal listings in LDAP.\n"));
517 krb5_kt_close(context
, keytab
);
520 krb5_free_context(context
);
525 /**********************************************************************
526 Adds all the required service principals to the system keytab.
527 ***********************************************************************/
529 int ads_keytab_create_default(ADS_STRUCT
*ads
)
531 krb5_error_code ret
= 0;
532 krb5_context context
= NULL
;
533 krb5_keytab keytab
= NULL
;
534 krb5_kt_cursor cursor
= {0};
535 krb5_keytab_entry kt_entry
= {0};
538 char *sam_account_name
, *upn
;
539 char **oldEntries
= NULL
, *princ_s
[26];
548 ZERO_STRUCT(kt_entry
);
551 frame
= talloc_stackframe();
557 status
= ads_get_service_principal_names(frame
,
562 if (!ADS_ERR_OK(status
)) {
567 for (i
= 0; i
< num_spns
; i
++) {
571 srv_princ
= strlower_talloc(frame
, spn_array
[i
]);
572 if (srv_princ
== NULL
) {
577 p
= strchr_m(srv_princ
, '/');
583 /* Add the SPNs found on the DC */
584 ret
= ads_keytab_add_entry(ads
, srv_princ
, false);
586 DEBUG(1, ("ads_keytab_add_entry failed while "
587 "adding '%s' principal.\n",
593 #if 0 /* don't create the CIFS/... keytab entries since no one except smbd
594 really needs them and we will fall back to verifying against
597 ret
= ads_keytab_add_entry(ads
, "cifs", false));
599 DEBUG(1, (__location__
": ads_keytab_add_entry failed while "
600 "adding 'cifs'.\n"));
605 memset(princ_s
, '\0', sizeof(princ_s
));
607 ret
= smb_krb5_init_context_common(&context
);
609 DBG_ERR("kerberos init context failed (%s)\n",
614 machine_name
= talloc_strdup(frame
, lp_netbios_name());
620 /* now add the userPrincipalName and sAMAccountName entries */
621 ok
= ads_has_samaccountname(ads
, frame
, machine_name
);
623 DEBUG(0, (__location__
": unable to determine machine "
624 "account's name in AD!\n"));
630 * append '$' to netbios name so 'ads_keytab_add_entry' recognises
631 * it as a machine account rather than a service or Windows SPN.
633 sam_account_name
= talloc_asprintf(frame
, "%s$",machine_name
);
634 if (sam_account_name
== NULL
) {
638 /* upper case the sAMAccountName to make it easier for apps to
639 know what case to use in the keytab file */
640 if (!strupper_m(sam_account_name
)) {
645 ret
= ads_keytab_add_entry(ads
, sam_account_name
, false);
647 DEBUG(1, (__location__
": ads_keytab_add_entry() failed "
648 "while adding sAMAccountName (%s)\n",
653 /* remember that not every machine account will have a upn */
654 upn
= ads_get_upn(ads
, frame
, machine_name
);
656 ret
= ads_keytab_add_entry(ads
, upn
, false);
658 DEBUG(1, (__location__
": ads_keytab_add_entry() "
659 "failed while adding UPN (%s)\n", upn
));
664 /* Now loop through the keytab and update any other existing entries */
665 kvno
= (krb5_kvno
)ads_get_machine_kvno(ads
, machine_name
);
666 if (kvno
== (krb5_kvno
)-1) {
667 DEBUG(1, (__location__
": ads_get_machine_kvno() failed to "
668 "determine the system's kvno.\n"));
672 DEBUG(3, (__location__
": Searching for keytab entries to preserve "
675 ret
= ads_keytab_open(context
, &keytab
);
680 ret
= krb5_kt_start_seq_get(context
, keytab
, &cursor
);
681 if (ret
!= KRB5_KT_END
&& ret
!= ENOENT
) {
682 while ((ret
= krb5_kt_next_entry(context
, keytab
,
683 &kt_entry
, &cursor
)) == 0) {
684 smb_krb5_kt_free_entry(context
, &kt_entry
);
685 ZERO_STRUCT(kt_entry
);
689 krb5_kt_end_seq_get(context
, keytab
, &cursor
);
693 * Hmmm. There is no "rewind" function for the keytab. This means we
694 * have a race condition where someone else could add entries after
695 * we've counted them. Re-open asap to minimise the race. JRA.
697 DEBUG(3, (__location__
": Found %zd entries in the keytab.\n", found
));
702 oldEntries
= talloc_zero_array(frame
, char *, found
+ 1);
704 DEBUG(1, (__location__
": Failed to allocate space to store "
705 "the old keytab entries (talloc failed?).\n"));
710 ret
= krb5_kt_start_seq_get(context
, keytab
, &cursor
);
711 if (ret
== KRB5_KT_END
|| ret
== ENOENT
) {
712 krb5_kt_end_seq_get(context
, keytab
, &cursor
);
717 while (krb5_kt_next_entry(context
, keytab
, &kt_entry
, &cursor
) == 0) {
718 if (kt_entry
.vno
!= kvno
) {
719 char *ktprinc
= NULL
;
722 /* This returns a malloc'ed string in ktprinc. */
723 ret
= smb_krb5_unparse_name(oldEntries
, context
,
727 DEBUG(1, (__location__
728 ": smb_krb5_unparse_name failed "
729 "(%s)\n", error_message(ret
)));
733 * From looking at the krb5 source they don't seem to
734 * take locale or mb strings into account.
735 * Maybe this is because they assume utf8 ?
736 * In this case we may need to convert from utf8 to
737 * mb charset here ? JRA.
739 p
= strchr_m(ktprinc
, '@');
744 p
= strchr_m(ktprinc
, '/');
748 for (i
= 0; i
< found
; i
++) {
749 if (!oldEntries
[i
]) {
750 oldEntries
[i
] = ktprinc
;
753 if (!strcmp(oldEntries
[i
], ktprinc
)) {
754 TALLOC_FREE(ktprinc
);
759 TALLOC_FREE(ktprinc
);
762 smb_krb5_kt_free_entry(context
, &kt_entry
);
763 ZERO_STRUCT(kt_entry
);
765 krb5_kt_end_seq_get(context
, keytab
, &cursor
);
769 for (i
= 0; oldEntries
[i
]; i
++) {
770 ret
|= ads_keytab_add_entry(ads
, oldEntries
[i
], false);
771 TALLOC_FREE(oldEntries
[i
]);
775 TALLOC_FREE(oldEntries
);
779 if (!all_zero((uint8_t *)&kt_entry
, sizeof(kt_entry
))) {
780 smb_krb5_kt_free_entry(context
, &kt_entry
);
782 if (!all_zero((uint8_t *)&cursor
, sizeof(cursor
)) && keytab
) {
783 krb5_kt_end_seq_get(context
, keytab
, &cursor
);
786 krb5_kt_close(context
, keytab
);
788 krb5_free_context(context
);
793 #endif /* HAVE_ADS */
795 /**********************************************************************
797 ***********************************************************************/
799 int ads_keytab_list(const char *keytab_name
)
801 krb5_error_code ret
= 0;
802 krb5_context context
= NULL
;
803 krb5_keytab keytab
= NULL
;
804 krb5_kt_cursor cursor
;
805 krb5_keytab_entry kt_entry
;
807 ZERO_STRUCT(kt_entry
);
810 ret
= smb_krb5_init_context_common(&context
);
812 DBG_ERR("kerberos init context failed (%s)\n",
817 if (keytab_name
== NULL
) {
819 ret
= ads_keytab_open(context
, &keytab
);
824 ret
= smb_krb5_kt_open(context
, keytab_name
, False
, &keytab
);
827 DEBUG(1, ("smb_krb5_kt_open failed (%s)\n",
828 error_message(ret
)));
832 ret
= krb5_kt_start_seq_get(context
, keytab
, &cursor
);
838 printf("Vno Type Principal\n");
840 while (krb5_kt_next_entry(context
, keytab
, &kt_entry
, &cursor
) == 0) {
842 char *princ_s
= NULL
;
843 char *etype_s
= NULL
;
844 krb5_enctype enctype
= 0;
846 ret
= smb_krb5_unparse_name(talloc_tos(), context
,
847 kt_entry
.principal
, &princ_s
);
852 enctype
= smb_krb5_kt_get_enctype_from_entry(&kt_entry
);
854 ret
= smb_krb5_enctype_to_string(context
, enctype
, &etype_s
);
856 (asprintf(&etype_s
, "UNKNOWN: %d\n", enctype
) == -1)) {
857 TALLOC_FREE(princ_s
);
861 printf("%3d %-43s %s\n", kt_entry
.vno
, etype_s
, princ_s
);
863 TALLOC_FREE(princ_s
);
866 ret
= smb_krb5_kt_free_entry(context
, &kt_entry
);
872 ret
= krb5_kt_end_seq_get(context
, keytab
, &cursor
);
877 /* Ensure we don't double free. */
878 ZERO_STRUCT(kt_entry
);
882 if (!all_zero((uint8_t *)&kt_entry
, sizeof(kt_entry
))) {
883 smb_krb5_kt_free_entry(context
, &kt_entry
);
885 if (!all_zero((uint8_t *)&cursor
, sizeof(cursor
)) && keytab
) {
886 krb5_kt_end_seq_get(context
, keytab
, &cursor
);
890 krb5_kt_close(context
, keytab
);
893 krb5_free_context(context
);
898 #endif /* HAVE_KRB5 */