s3:kerberos_verify: ads_dedicated_keytab_verify_ticket() only needs read access
[metze/samba/wip.git] / source3 / libads / kerberos_verify.c
index 03e30a9ba3ee7c48d2fba1e5c8724c50ee80be14..0c44db988e62e364816906388470339a5c9c673a 100644 (file)
@@ -1,29 +1,33 @@
-/* 
+/*
    Unix SMB/CIFS implementation.
    kerberos utility library
    Copyright (C) Andrew Tridgell 2001
    Copyright (C) Remus Koos 2001
-   Copyright (C) Luke Howard 2003   
+   Copyright (C) Luke Howard 2003
    Copyright (C) Guenther Deschner 2003, 2005
    Copyright (C) Jim McDonough (jmcd@us.ibm.com) 2003
    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004-2005
-   
+   Copyright (C) Jeremy Allison 2007
+
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2 of the License, or
+   the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.
-   
+
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
-   
+
    You should have received a copy of the GNU General Public License
-   along with this program; if not, write to the Free Software
-   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
 #include "includes.h"
+#include "smb_krb5.h"
+#include "libads/kerberos_proto.h"
+#include "secrets.h"
+#include "../librpc/gen_ndr/krb5pac.h"
 
 #ifdef HAVE_KRB5
 
 const krb5_data *krb5_princ_component(krb5_context, krb5_principal, int );
 #endif
 
-/**********************************************************************************
- Try to verify a ticket using the system keytab... the system keytab has kvno -1 entries, so
- it's more like what microsoft does... see comment in utils/net_ads.c in the
- ads_keytab_add_entry function for details.
-***********************************************************************************/
+static bool ads_dedicated_keytab_verify_ticket(krb5_context context,
+                                         krb5_auth_context auth_context,
+                                         const DATA_BLOB *ticket,
+                                         krb5_ticket **pp_tkt,
+                                         krb5_keyblock **keyblock,
+                                         krb5_error_code *perr)
+{
+       krb5_error_code ret = 0;
+       bool auth_ok = false;
+       krb5_keytab keytab = NULL;
+       krb5_keytab_entry kt_entry;
+       krb5_ticket *dec_ticket = NULL;
+
+       krb5_data packet;
+       krb5_kvno kvno = 0;
+       krb5_enctype enctype;
+
+       *pp_tkt = NULL;
+       *keyblock = NULL;
+       *perr = 0;
+
+       ZERO_STRUCT(kt_entry);
+
+       ret = smb_krb5_open_keytab(context, lp_dedicated_keytab_file(), false,
+           &keytab);
+       if (ret) {
+               DEBUG(1, ("smb_krb5_open_keytab failed (%s)\n",
+                       error_message(ret)));
+               goto out;
+       }
+
+       packet.length = ticket->length;
+       packet.data = (char *)ticket->data;
+
+       ret = krb5_rd_req(context, &auth_context, &packet, NULL, keytab,
+           NULL, &dec_ticket);
+       if (ret) {
+               DEBUG(0, ("krb5_rd_req failed (%s)\n", error_message(ret)));
+               goto out;
+       }
+
+#ifdef HAVE_ETYPE_IN_ENCRYPTEDDATA /* Heimdal */
+       enctype = dec_ticket->ticket.key.keytype;
+#else /* MIT */
+       enctype = dec_ticket->enc_part.enctype;
+       kvno    = dec_ticket->enc_part.kvno;
+#endif
+
+       /* Get the key for checking the pac signature */
+       ret = krb5_kt_get_entry(context, keytab, dec_ticket->server,
+                               kvno, enctype, &kt_entry);
+       if (ret) {
+               DEBUG(0, ("krb5_kt_get_entry failed (%s)\n",
+                         error_message(ret)));
+               goto out;
+       }
+
+       ret = krb5_copy_keyblock(context, KRB5_KT_KEY(&kt_entry), keyblock);
+       smb_krb5_kt_free_entry(context, &kt_entry);
+
+       if (ret) {
+               DEBUG(0, ("failed to copy key: %s\n",
+                         error_message(ret)));
+               goto out;
+       }
+
+       auth_ok = true;
+       *pp_tkt = dec_ticket;
+       dec_ticket = NULL;
+
+  out:
+       if (dec_ticket)
+               krb5_free_ticket(context, dec_ticket);
+
+       if (keytab)
+               krb5_kt_close(context, keytab);
+
+       *perr = ret;
+       return auth_ok;
+}
 
-static BOOL ads_keytab_verify_ticket(krb5_context context, krb5_auth_context auth_context,
-                       const DATA_BLOB *ticket, krb5_data *p_packet, krb5_ticket **pp_tkt, 
-                       krb5_keyblock **keyblock)
+/******************************************************************************
+ Try to verify a ticket using the system keytab... the system keytab has
+ kvno -1 entries, so it's more like what microsoft does... see comment in
+ utils/net_ads.c in the ads_keytab_add_entry function for details.
+******************************************************************************/
+
+static bool ads_keytab_verify_ticket(krb5_context context,
+                                       krb5_auth_context auth_context,
+                                       const DATA_BLOB *ticket,
+                                       krb5_ticket **pp_tkt,
+                                       krb5_keyblock **keyblock,
+                                       krb5_error_code *perr)
 {
        krb5_error_code ret = 0;
-       BOOL auth_ok = False;
+       bool auth_ok = False;
        krb5_keytab keytab = NULL;
        krb5_kt_cursor kt_cursor;
        krb5_keytab_entry kt_entry;
-       char *valid_princ_formats[7] = { NULL, NULL, NULL, NULL, NULL, NULL, NULL };
+       char *valid_princ_formats[7] = { NULL, NULL, NULL,
+                                        NULL, NULL, NULL, NULL };
        char *entry_princ_s = NULL;
        fstring my_name, my_fqdn;
        int i;
        int number_matched_principals = 0;
+       krb5_data packet;
+       int err;
+
+       *pp_tkt = NULL;
+       *keyblock = NULL;
+       *perr = 0;
 
        /* Generate the list of principal names which we expect
         * clients might want to use for authenticating to the file
         * service.  We allow name$,{host,cifs}/{name,fqdn,name.REALM}. */
 
-       fstrcpy(my_name, global_myname());
+       fstrcpy(my_name, lp_netbios_name());
 
        my_fqdn[0] = '\0';
-       name_to_fqdn(my_fqdn, global_myname());
+       name_to_fqdn(my_fqdn, lp_netbios_name());
 
-       asprintf(&valid_princ_formats[0], "%s$@%s", my_name, lp_realm());
-       asprintf(&valid_princ_formats[1], "host/%s@%s", my_name, lp_realm());
-       asprintf(&valid_princ_formats[2], "host/%s@%s", my_fqdn, lp_realm());
-       asprintf(&valid_princ_formats[3], "host/%s.%s@%s", my_name, lp_realm(), lp_realm());
-       asprintf(&valid_princ_formats[4], "cifs/%s@%s", my_name, lp_realm());
-       asprintf(&valid_princ_formats[5], "cifs/%s@%s", my_fqdn, lp_realm());
-       asprintf(&valid_princ_formats[6], "cifs/%s.%s@%s", my_name, lp_realm(), lp_realm());
+       err = asprintf(&valid_princ_formats[0],
+                       "%s$@%s", my_name, lp_realm());
+       if (err == -1) {
+               goto out;
+       }
+       err = asprintf(&valid_princ_formats[1],
+                       "host/%s@%s", my_name, lp_realm());
+       if (err == -1) {
+               goto out;
+       }
+       err = asprintf(&valid_princ_formats[2],
+                       "host/%s@%s", my_fqdn, lp_realm());
+       if (err == -1) {
+               goto out;
+       }
+       err = asprintf(&valid_princ_formats[3],
+                       "host/%s.%s@%s", my_name, lp_realm(), lp_realm());
+       if (err == -1) {
+               goto out;
+       }
+       err = asprintf(&valid_princ_formats[4],
+                       "cifs/%s@%s", my_name, lp_realm());
+       if (err == -1) {
+               goto out;
+       }
+       err = asprintf(&valid_princ_formats[5],
+                       "cifs/%s@%s", my_fqdn, lp_realm());
+       if (err == -1) {
+               goto out;
+       }
+       err = asprintf(&valid_princ_formats[6],
+                       "cifs/%s.%s@%s", my_name, lp_realm(), lp_realm());
+       if (err == -1) {
+               goto out;
+       }
 
        ZERO_STRUCT(kt_entry);
        ZERO_STRUCT(kt_cursor);
 
-       ret = krb5_kt_default(context, &keytab);
+       ret = smb_krb5_open_keytab(context, NULL, False, &keytab);
        if (ret) {
-               DEBUG(1, ("ads_keytab_verify_ticket: krb5_kt_default failed (%s)\n", error_message(ret)));
+               DEBUG(1, (__location__ ": smb_krb5_open_keytab failed (%s)\n",
+                         error_message(ret)));
                goto out;
        }
 
@@ -84,91 +208,103 @@ static BOOL ads_keytab_verify_ticket(krb5_context context, krb5_auth_context aut
 
        ret = krb5_kt_start_seq_get(context, keytab, &kt_cursor);
        if (ret) {
-               DEBUG(1, ("ads_keytab_verify_ticket: krb5_kt_start_seq_get failed (%s)\n", error_message(ret)));
+               DEBUG(1, (__location__ ": krb5_kt_start_seq_get failed (%s)\n",
+                         error_message(ret)));
                goto out;
        }
   
-               while (!auth_ok && (krb5_kt_next_entry(context, keytab, &kt_entry, &kt_cursor) == 0)) {
-                       ret = smb_krb5_unparse_name(context, kt_entry.principal, &entry_princ_s);
-                       if (ret) {
-                               DEBUG(1, ("ads_keytab_verify_ticket: smb_krb5_unparse_name failed (%s)\n",
-                                       error_message(ret)));
-                               goto out;
+       while (!auth_ok &&
+              (krb5_kt_next_entry(context, keytab,
+                                  &kt_entry, &kt_cursor) == 0)) {
+               ret = smb_krb5_unparse_name(talloc_tos(), context,
+                                           kt_entry.principal,
+                                           &entry_princ_s);
+               if (ret) {
+                       DEBUG(1, (__location__ ": smb_krb5_unparse_name "
+                                 "failed (%s)\n", error_message(ret)));
+                       goto out;
+               }
+
+               for (i = 0; i < ARRAY_SIZE(valid_princ_formats); i++) {
+
+                       if (!strequal(entry_princ_s, valid_princ_formats[i])) {
+                               continue;
                        }
 
-                       for (i = 0; i < sizeof(valid_princ_formats) / sizeof(valid_princ_formats[0]); i++) {
-                               if (strequal(entry_princ_s, valid_princ_formats[i])) {
-                                       number_matched_principals++;
-                                       p_packet->length = ticket->length;
-                                       p_packet->data = (char *)ticket->data;
-                                       *pp_tkt = NULL;
-
-                                       ret = krb5_rd_req_return_keyblock_from_keytab(context, &auth_context, p_packet,
-                                                                                     kt_entry.principal, keytab,
-                                                                                     NULL, pp_tkt, keyblock);
-
-                                       if (ret) {
-                                               DEBUG(10,("ads_keytab_verify_ticket: "
-                                                       "krb5_rd_req_return_keyblock_from_keytab(%s) failed: %s\n",
-                                                       entry_princ_s, error_message(ret)));
-
-                                               /* workaround for MIT: 
-                                                * as krb5_ktfile_get_entry will
-                                                * explicitly close the
-                                                * krb5_keytab as soon as
-                                                * krb5_rd_req has sucessfully
-                                                * decrypted the ticket but the
-                                                * ticket is not valid yet (due
-                                                * to clockskew) there is no
-                                                * point in querying more
-                                                * keytab entries - Guenther */
-                                               
-                                               if (ret == KRB5KRB_AP_ERR_TKT_NYV || 
-                                                   ret == KRB5KRB_AP_ERR_TKT_EXPIRED) {
-                                                       break;
-                                               }
-                                       } else {
-                                               DEBUG(3,("ads_keytab_verify_ticket: "
-                                                       "krb5_rd_req_return_keyblock_from_keytab succeeded for principal %s\n",
-                                                       entry_princ_s));
-                                               auth_ok = True;
-                                               break;
-                                       }
+                       number_matched_principals++;
+                       packet.length = ticket->length;
+                       packet.data = (char *)ticket->data;
+                       *pp_tkt = NULL;
+
+                       ret = krb5_rd_req_return_keyblock_from_keytab(context,
+                                               &auth_context, &packet,
+                                               kt_entry.principal, keytab,
+                                               NULL, pp_tkt, keyblock);
+
+                       if (ret) {
+                               DEBUG(10, (__location__ ": krb5_rd_req_return"
+                                          "_keyblock_from_keytab(%s) "
+                                          "failed: %s\n", entry_princ_s,
+                                          error_message(ret)));
+
+                               /* workaround for MIT:
+                               * as krb5_ktfile_get_entry will explicitly
+                               * close the krb5_keytab as soon as krb5_rd_req
+                               * has successfully decrypted the ticket but the
+                               * ticket is not valid yet (due to clockskew)
+                               * there is no point in querying more keytab
+                               * entries - Guenther */
+
+                               if (ret == KRB5KRB_AP_ERR_TKT_NYV ||
+                                   ret == KRB5KRB_AP_ERR_TKT_EXPIRED ||
+                                   ret == KRB5KRB_AP_ERR_SKEW) {
+                                       break;
                                }
+                       } else {
+                               DEBUG(3, (__location__ ": krb5_rd_req_return"
+                                         "_keyblock_from_keytab succeeded "
+                                         "for principal %s\n",
+                                         entry_princ_s));
+                               auth_ok = True;
+                               break;
                        }
+               }
 
-                       /* Free the name we parsed. */
-                       SAFE_FREE(entry_princ_s);
+               /* Free the name we parsed. */
+               TALLOC_FREE(entry_princ_s);
 
-                       /* Free the entry we just read. */
-                       smb_krb5_kt_free_entry(context, &kt_entry);
-                       ZERO_STRUCT(kt_entry);
-               }
-               krb5_kt_end_seq_get(context, keytab, &kt_cursor);
+               /* Free the entry we just read. */
+               smb_krb5_kt_free_entry(context, &kt_entry);
+               ZERO_STRUCT(kt_entry);
+       }
+       krb5_kt_end_seq_get(context, keytab, &kt_cursor);
 
        ZERO_STRUCT(kt_cursor);
 
-  out:
-       
-       for (i = 0; i < sizeof(valid_princ_formats) / sizeof(valid_princ_formats[0]); i++) {
+out:
+
+       for (i = 0; i < ARRAY_SIZE(valid_princ_formats); i++) {
                SAFE_FREE(valid_princ_formats[i]);
        }
-       
+
        if (!auth_ok) {
                if (!number_matched_principals) {
-                       DEBUG(3, ("ads_keytab_verify_ticket: no keytab principals matched expected file service name.\n"));
+                       DEBUG(3, (__location__ ": no keytab principals "
+                                 "matched expected file service name.\n"));
                } else {
-                       DEBUG(3, ("ads_keytab_verify_ticket: krb5_rd_req failed for all %d matched keytab principals\n",
-                               number_matched_principals));
+                       DEBUG(3, (__location__ ": krb5_rd_req failed for "
+                                 "all %d matched keytab principals\n",
+                                 number_matched_principals));
                }
        }
 
-       SAFE_FREE(entry_princ_s);
+       TALLOC_FREE(entry_princ_s);
 
        {
                krb5_keytab_entry zero_kt_entry;
                ZERO_STRUCT(zero_kt_entry);
-               if (memcmp(&zero_kt_entry, &kt_entry, sizeof(krb5_keytab_entry))) {
+               if (memcmp(&zero_kt_entry, &kt_entry,
+                          sizeof(krb5_keytab_entry))) {
                        smb_krb5_kt_free_entry(context, &kt_entry);
                }
        }
@@ -176,7 +312,8 @@ static BOOL ads_keytab_verify_ticket(krb5_context context, krb5_auth_context aut
        {
                krb5_kt_cursor zero_csr;
                ZERO_STRUCT(zero_csr);
-               if ((memcmp(&kt_cursor, &zero_csr, sizeof(krb5_kt_cursor)) != 0) && keytab) {
+               if ((memcmp(&kt_cursor, &zero_csr,
+                           sizeof(krb5_kt_cursor)) != 0) && keytab) {
                        krb5_kt_end_seq_get(context, keytab, &kt_cursor);
                }
        }
@@ -184,107 +321,154 @@ static BOOL ads_keytab_verify_ticket(krb5_context context, krb5_auth_context aut
        if (keytab) {
                krb5_kt_close(context, keytab);
        }
+       *perr = ret;
        return auth_ok;
 }
 
-/**********************************************************************************
+/*****************************************************************************
  Try to verify a ticket using the secrets.tdb.
-***********************************************************************************/
-
-static BOOL ads_secrets_verify_ticket(krb5_context context, krb5_auth_context auth_context,
-                                     krb5_principal host_princ,
-                                     const DATA_BLOB *ticket, krb5_data *p_packet, krb5_ticket **pp_tkt,
-                                     krb5_keyblock **keyblock)
+******************************************************************************/
+
+static krb5_error_code ads_secrets_verify_ticket(krb5_context context,
+                                               krb5_auth_context auth_context,
+                                               krb5_principal host_princ,
+                                               const DATA_BLOB *ticket,
+                                               krb5_ticket **pp_tkt,
+                                               krb5_keyblock **keyblock,
+                                               krb5_error_code *perr)
 {
        krb5_error_code ret = 0;
-       BOOL auth_ok = False;
+       bool auth_ok = False;
+       bool cont = true;
        char *password_s = NULL;
-       krb5_data password;
-       krb5_enctype enctypes[4] = { ENCTYPE_DES_CBC_CRC, ENCTYPE_DES_CBC_MD5, 0, 0 };
-       int i;
+       /* Let's make some room for 2 password (old and new)*/
+       krb5_data passwords[2];
+       krb5_enctype enctypes[] = {
+               ENCTYPE_ARCFOUR_HMAC,
+               ENCTYPE_DES_CBC_CRC,
+               ENCTYPE_DES_CBC_MD5,
+               ENCTYPE_NULL
+       };
+       krb5_data packet;
+       int i, j;
 
-#if defined(ENCTYPE_ARCFOUR_HMAC)
-       enctypes[2] = ENCTYPE_ARCFOUR_HMAC;
-#endif
+       *pp_tkt = NULL;
+       *keyblock = NULL;
+       *perr = 0;
 
-       ZERO_STRUCTP(keyblock);
+       ZERO_STRUCT(passwords);
 
        if (!secrets_init()) {
                DEBUG(1,("ads_secrets_verify_ticket: secrets_init failed\n"));
+               *perr = KRB5_CONFIG_CANTOPEN;
                return False;
        }
 
-       password_s = secrets_fetch_machine_password(lp_workgroup(), NULL, NULL);
+       password_s = secrets_fetch_machine_password(lp_workgroup(),
+                                                   NULL, NULL);
        if (!password_s) {
-               DEBUG(1,("ads_secrets_verify_ticket: failed to fetch machine password\n"));
+               DEBUG(1,(__location__ ": failed to fetch machine password\n"));
+               *perr = KRB5_LIBOS_CANTREADPWD;
                return False;
        }
 
-       password.data = password_s;
-       password.length = strlen(password_s);
+       passwords[0].data = password_s;
+       passwords[0].length = strlen(password_s);
+
+       password_s = secrets_fetch_prev_machine_password(lp_workgroup());
+       if (password_s) {
+               DEBUG(10, (__location__ ": found previous password\n"));
+               passwords[1].data = password_s;
+               passwords[1].length = strlen(password_s);
+       }
 
        /* CIFS doesn't use addresses in tickets. This would break NAT. JRA */
 
-       p_packet->length = ticket->length;
-       p_packet->data = (char *)ticket->data;
+       packet.length = ticket->length;
+       packet.data = (char *)ticket->data;
 
-       /* We need to setup a auth context with each possible encoding type in turn. */
-       for (i=0;enctypes[i];i++) {
-               krb5_keyblock *key = NULL;
+       /* We need to setup a auth context with each possible encoding type
+        * in turn. */
+       for (j=0; j<2 && passwords[j].length; j++) {
 
-               if (!(key = SMB_MALLOC_P(krb5_keyblock))) {
-                       goto out;
-               }
-       
-               if (create_kerberos_key_from_string(context, host_princ, &password, key, enctypes[i])) {
-                       SAFE_FREE(key);
-                       continue;
-               }
+               for (i=0;enctypes[i];i++) {
+                       krb5_keyblock *key = NULL;
 
-               krb5_auth_con_setuseruserkey(context, auth_context, key);
+                       if (!(key = SMB_MALLOC_P(krb5_keyblock))) {
+                               ret = ENOMEM;
+                               goto out;
+                       }
 
-               if (!(ret = krb5_rd_req(context, &auth_context, p_packet, 
-                                       NULL,
-                                       NULL, NULL, pp_tkt))) {
-                       DEBUG(10,("ads_secrets_verify_ticket: enc type [%u] decrypted message !\n",
-                               (unsigned int)enctypes[i] ));
-                       auth_ok = True;
-                       krb5_copy_keyblock(context, key, keyblock);
-                       krb5_free_keyblock(context, key);
-                       break;
-               }
+                       if (create_kerberos_key_from_string(context,
+                                               host_princ, &passwords[j],
+                                               key, enctypes[i], false)) {
+                               SAFE_FREE(key);
+                               continue;
+                       }
+
+                       krb5_auth_con_setuseruserkey(context,
+                                                       auth_context, key);
+
+                       if (!(ret = krb5_rd_req(context, &auth_context,
+                                               &packet, NULL, NULL,
+                                               NULL, pp_tkt))) {
+                               DEBUG(10, (__location__ ": enc type [%u] "
+                                          "decrypted message !\n",
+                                          (unsigned int)enctypes[i]));
+                               auth_ok = True;
+                               cont = false;
+                               krb5_copy_keyblock(context, key, keyblock);
+                               krb5_free_keyblock(context, key);
+                               break;
+                       }
 
-               DEBUG((ret != KRB5_BAD_ENCTYPE) ? 3 : 10,
-                               ("ads_secrets_verify_ticket: enc type [%u] failed to decrypt with error %s\n",
-                               (unsigned int)enctypes[i], error_message(ret)));
+                       DEBUG((ret != KRB5_BAD_ENCTYPE) ? 3 : 10,
+                               (__location__ ": enc type [%u] failed to "
+                                "decrypt with error %s\n",
+                                (unsigned int)enctypes[i],
+                                error_message(ret)));
+
+                       /* successfully decrypted but ticket is just not
+                        * valid at the moment */
+                       if (ret == KRB5KRB_AP_ERR_TKT_NYV ||
+                           ret == KRB5KRB_AP_ERR_TKT_EXPIRED ||
+                           ret == KRB5KRB_AP_ERR_SKEW) {
+                               krb5_free_keyblock(context, key);
+                               cont = false;
+                               break;
+                       }
 
-               /* successfully decrypted but ticket is just not valid at the moment */
-               if (ret == KRB5KRB_AP_ERR_TKT_NYV || 
-                   ret == KRB5KRB_AP_ERR_TKT_EXPIRED) {
+                       krb5_free_keyblock(context, key);
+               }
+               if (!cont) {
+                       /* If we found a valid pass then no need to try
+                        * the next one or we have invalid ticket so no need
+                        * to try next password*/
                        break;
                }
-
-               krb5_free_keyblock(context, key);
-
        }
 
  out:
-       SAFE_FREE(password_s);
-
+       SAFE_FREE(passwords[0].data);
+       SAFE_FREE(passwords[1].data);
+       *perr = ret;
        return auth_ok;
 }
 
-/**********************************************************************************
- Verify an incoming ticket and parse out the principal name and 
+/*****************************************************************************
+ Verify an incoming ticket and parse out the principal name and
  authorization_data if available.
-***********************************************************************************/
+******************************************************************************/
 
 NTSTATUS ads_verify_ticket(TALLOC_CTX *mem_ctx,
-                          const char *realm, time_t time_offset,
-                          const DATA_BLOB *ticket, 
-                          char **principal, PAC_DATA **pac_data,
+                          const char *realm,
+                          time_t time_offset,
+                          const DATA_BLOB *ticket,
+                          char **principal,
+                          struct PAC_LOGON_INFO **logon_info,
                           DATA_BLOB *ap_rep,
-                          DATA_BLOB *session_key)
+                          DATA_BLOB *session_key,
+                          bool use_replay_cache)
 {
        NTSTATUS sret = NT_STATUS_LOGON_FAILURE;
        NTSTATUS pac_ret;
@@ -296,25 +480,28 @@ NTSTATUS ads_verify_ticket(TALLOC_CTX *mem_ctx,
        krb5_rcache rcache = NULL;
        krb5_keyblock *keyblock = NULL;
        time_t authtime;
-       int ret;
-
+       krb5_error_code ret = 0;
+       int flags = 0;
        krb5_principal host_princ = NULL;
        krb5_const_principal client_principal = NULL;
        char *host_princ_s = NULL;
-       BOOL got_replay_mutex = False;
-
-       BOOL auth_ok = False;
-       BOOL got_auth_data = False;
+       bool auth_ok = False;
+       bool got_auth_data = False;
+       struct named_mutex *mutex = NULL;
 
        ZERO_STRUCT(packet);
        ZERO_STRUCT(auth_data);
-       ZERO_STRUCTP(ap_rep);
-       ZERO_STRUCTP(session_key);
+
+       *principal = NULL;
+       *logon_info = NULL;
+       *ap_rep = data_blob_null;
+       *session_key = data_blob_null;
 
        initialize_krb5_error_table();
        ret = krb5_init_context(&context);
        if (ret) {
-               DEBUG(1,("ads_verify_ticket: krb5_init_context failed (%s)\n", error_message(ret)));
+               DEBUG(1, (__location__ ": krb5_init_context failed (%s)\n",
+                         error_message(ret)));
                return NT_STATUS_LOGON_FAILURE;
        }
 
@@ -324,7 +511,8 @@ NTSTATUS ads_verify_ticket(TALLOC_CTX *mem_ctx,
 
        ret = krb5_set_default_realm(context, realm);
        if (ret) {
-               DEBUG(1,("ads_verify_ticket: krb5_set_default_realm failed (%s)\n", error_message(ret)));
+               DEBUG(1, (__location__ ": krb5_set_default_realm "
+                         "failed (%s)\n", error_message(ret)));
                goto out;
        }
 
@@ -334,108 +522,189 @@ NTSTATUS ads_verify_ticket(TALLOC_CTX *mem_ctx,
 
        ret = krb5_auth_con_init(context, &auth_context);
        if (ret) {
-               DEBUG(1,("ads_verify_ticket: krb5_auth_con_init failed (%s)\n", error_message(ret)));
+               DEBUG(1, (__location__ ": krb5_auth_con_init failed (%s)\n",
+                         error_message(ret)));
+               goto out;
+       }
+
+       krb5_auth_con_getflags( context, auth_context, &flags );
+       if ( !use_replay_cache ) {
+               /* Disable default use of a replay cache */
+               flags &= ~KRB5_AUTH_CONTEXT_DO_TIME;
+               krb5_auth_con_setflags( context, auth_context, flags );
+       }
+
+       if (asprintf(&host_princ_s, "%s$", lp_netbios_name()) == -1) {
                goto out;
        }
 
-       asprintf(&host_princ_s, "%s$", global_myname());
        strlower_m(host_princ_s);
        ret = smb_krb5_parse_name(context, host_princ_s, &host_princ);
        if (ret) {
-               DEBUG(1,("ads_verify_ticket: smb_krb5_parse_name(%s) failed (%s)\n",
-                                       host_princ_s, error_message(ret)));
+               DEBUG(1, (__location__ ": smb_krb5_parse_name(%s) "
+                         "failed (%s)\n", host_princ_s, error_message(ret)));
                goto out;
        }
 
 
-       /* Lock a mutex surrounding the replay as there is no locking in the MIT krb5
-        * code surrounding the replay cache... */
+       if (use_replay_cache) {
 
-       if (!grab_server_mutex("replay cache mutex")) {
-               DEBUG(1,("ads_verify_ticket: unable to protect replay cache with mutex.\n"));
-               goto out;
-       }
+               /* Lock a mutex surrounding the replay as there is no
+                  locking in the MIT krb5 code surrounding the replay
+                  cache... */
 
-       got_replay_mutex = True;
+               mutex = grab_named_mutex(talloc_tos(),
+                                        "replay cache mutex", 10);
+               if (mutex == NULL) {
+                       DEBUG(1, (__location__ ": unable to protect replay "
+                                 "cache with mutex.\n"));
+                       ret = KRB5_CC_IO;
+                       goto out;
+               }
 
-       /*
-        * JRA. We must set the rcache here. This will prevent replay attacks.
-        */
+               /* JRA. We must set the rcache here. This will prevent
+                  replay attacks. */
 
-       ret = krb5_get_server_rcache(context, krb5_princ_component(context, host_princ, 0), &rcache);
-       if (ret) {
-               DEBUG(1,("ads_verify_ticket: krb5_get_server_rcache failed (%s)\n", error_message(ret)));
-               goto out;
-       }
+               ret = krb5_get_server_rcache(
+                               context,
+                               krb5_princ_component(context, host_princ, 0),
+                               &rcache);
+               if (ret) {
+                       DEBUG(1, (__location__ ": krb5_get_server_rcache "
+                                 "failed (%s)\n", error_message(ret)));
+                       goto out;
+               }
 
-       ret = krb5_auth_con_setrcache(context, auth_context, rcache);
-       if (ret) {
-               DEBUG(1,("ads_verify_ticket: krb5_auth_con_setrcache failed (%s)\n", error_message(ret)));
-               goto out;
+               ret = krb5_auth_con_setrcache(context, auth_context, rcache);
+               if (ret) {
+                       DEBUG(1, (__location__ ": krb5_auth_con_setrcache "
+                                 "failed (%s)\n", error_message(ret)));
+                       goto out;
+               }
        }
 
-       if (lp_use_kerberos_keytab()) {
-               auth_ok = ads_keytab_verify_ticket(context, auth_context, ticket, &packet, &tkt, &keyblock);
-       }
-       if (!auth_ok) {
-               auth_ok = ads_secrets_verify_ticket(context, auth_context, host_princ,
-                                                   ticket, &packet, &tkt, &keyblock);
+       switch (lp_kerberos_method()) {
+       default:
+       case KERBEROS_VERIFY_SECRETS:
+               auth_ok = ads_secrets_verify_ticket(context, auth_context,
+                   host_princ, ticket, &tkt, &keyblock, &ret);
+               break;
+       case KERBEROS_VERIFY_SYSTEM_KEYTAB:
+               auth_ok = ads_keytab_verify_ticket(context, auth_context,
+                   ticket, &tkt, &keyblock, &ret);
+               break;
+       case KERBEROS_VERIFY_DEDICATED_KEYTAB:
+               auth_ok = ads_dedicated_keytab_verify_ticket(context,
+                   auth_context, ticket, &tkt, &keyblock, &ret);
+               break;
+       case KERBEROS_VERIFY_SECRETS_AND_KEYTAB:
+               /* First try secrets.tdb and fallback to the krb5.keytab if
+                  necessary.  This is the pre 3.4 behavior when
+                  "use kerberos keytab" was true.*/
+               auth_ok = ads_secrets_verify_ticket(context, auth_context,
+                   host_princ, ticket, &tkt, &keyblock, &ret);
+
+               if (!auth_ok) {
+                       /* Only fallback if we failed to decrypt the ticket */
+                       if (ret != KRB5KRB_AP_ERR_TKT_NYV &&
+                           ret != KRB5KRB_AP_ERR_TKT_EXPIRED &&
+                           ret != KRB5KRB_AP_ERR_SKEW) {
+                               auth_ok = ads_keytab_verify_ticket(context,
+                                   auth_context, ticket, &tkt, &keyblock,
+                                   &ret);
+                       }
+               }
+               break;
        }
 
-       release_server_mutex();
-       got_replay_mutex = False;
-
+       if (use_replay_cache) {
+               TALLOC_FREE(mutex);
 #if 0
-       /* Heimdal leaks here, if we fix the leak, MIT crashes */
-       if (rcache) {
-               krb5_rc_close(context, rcache);
-       }
+               /* Heimdal leaks here, if we fix the leak, MIT crashes */
+               if (rcache) {
+                       krb5_rc_close(context, rcache);
+               }
 #endif
+       }
 
        if (!auth_ok) {
-               DEBUG(3,("ads_verify_ticket: krb5_rd_req with auth failed (%s)\n", 
-                        error_message(ret)));
+               DEBUG(3, (__location__ ": krb5_rd_req with auth "
+                         "failed (%s)\n", error_message(ret)));
+               /* Try map the error return in case it's something like
+                * a clock skew error.
+                */
+               sret = krb5_to_nt_status(ret);
+               if (NT_STATUS_IS_OK(sret) ||
+                   NT_STATUS_EQUAL(sret,NT_STATUS_UNSUCCESSFUL)) {
+                       sret = NT_STATUS_LOGON_FAILURE;
+               }
+               DEBUG(10, (__location__ ": returning error %s\n",
+                          nt_errstr(sret) ));
                goto out;
-       } 
-       
+       }
+
        authtime = get_authtime_from_tkt(tkt);
        client_principal = get_principal_from_tkt(tkt);
 
        ret = krb5_mk_rep(context, auth_context, &packet);
        if (ret) {
-               DEBUG(3,("ads_verify_ticket: Failed to generate mutual authentication reply (%s)\n",
-                       error_message(ret)));
+               DEBUG(3, (__location__ ": Failed to generate mutual "
+                         "authentication reply (%s)\n", error_message(ret)));
                goto out;
        }
 
        *ap_rep = data_blob(packet.data, packet.length);
-       SAFE_FREE(packet.data);
-       packet.length = 0;
+       if (packet.data) {
+               kerberos_free_data_contents(context, &packet);
+               ZERO_STRUCT(packet);
+       }
 
-       get_krb5_smb_session_key(context, auth_context, session_key, True);
-       dump_data_pw("SMB session key (from ticket)\n", session_key->data, session_key->length);
+       get_krb5_smb_session_key(mem_ctx, context,
+                                auth_context, session_key, true);
+       dump_data_pw("SMB session key (from ticket)\n",
+                    session_key->data, session_key->length);
 
 #if 0
        file_save("/tmp/ticket.dat", ticket->data, ticket->length);
 #endif
 
-       /* continue when no PAC is retrieved or we couldn't decode the PAC 
+       /* continue when no PAC is retrieved or we couldn't decode the PAC
           (like accounts that have the UF_NO_AUTH_DATA_REQUIRED flag set, or
           Kerberos tickets encrypted using a DES key) - Guenther */
 
        got_auth_data = get_auth_data_from_tkt(mem_ctx, &auth_data, tkt);
        if (!got_auth_data) {
-               DEBUG(3,("ads_verify_ticket: did not retrieve auth data. continuing without PAC\n"));
+               DEBUG(3, (__location__ ": did not retrieve auth data. "
+                         "continuing without PAC\n"));
        }
 
-       if (got_auth_data && pac_data != NULL) {
-
-               pac_ret = decode_pac_data(mem_ctx, &auth_data, context, keyblock, client_principal, authtime, pac_data);
+       if (got_auth_data) {
+               struct PAC_DATA *pac_data;
+               pac_ret = kerberos_decode_pac(mem_ctx, auth_data, context,
+                                             NULL, keyblock, client_principal,
+                                             authtime, &pac_data);
+               data_blob_free(&auth_data);
                if (!NT_STATUS_IS_OK(pac_ret)) {
-                       DEBUG(3,("ads_verify_ticket: failed to decode PAC_DATA: %s\n", nt_errstr(pac_ret)));
-                       *pac_data = NULL;
+                       DEBUG(3, (__location__ ": failed to decode "
+                                 "PAC_DATA: %s\n", nt_errstr(pac_ret)));
+               } else {
+                       uint32_t i;
+                       for (i = 0; i < pac_data->num_buffers; i++) {
+
+                               if (pac_data->buffers[i].type != PAC_TYPE_LOGON_INFO) {
+                                       continue;
+                               }
+
+                               *logon_info = pac_data->buffers[i].info->logon_info.info;
+                       }
+
+                       if (!*logon_info) {
+                               DEBUG(1, ("correctly decoded PAC but found "
+                                         "no logon_info! "
+                                         "This should not happen\n"));
+                               return NT_STATUS_INVALID_USER_BUFFER;
+                       }
                }
-               data_blob_free(&auth_data);
        }
 
 #if 0
@@ -456,20 +725,20 @@ NTSTATUS ads_verify_ticket(TALLOC_CTX *mem_ctx,
 #endif
 #endif
 
-       if ((ret = smb_krb5_unparse_name(context, client_principal, principal))) {
-               DEBUG(3,("ads_verify_ticket: smb_krb5_unparse_name failed (%s)\n", 
-                        error_message(ret)));
+       ret = smb_krb5_unparse_name(mem_ctx, context,
+                                   client_principal, principal);
+       if (ret) {
+               DEBUG(3, (__location__ ": smb_krb5_unparse_name "
+                         "failed (%s)\n", error_message(ret)));
                sret = NT_STATUS_LOGON_FAILURE;
                goto out;
        }
 
        sret = NT_STATUS_OK;
 
- out:
+out:
 
-       if (got_replay_mutex) {
-               release_server_mutex();
-       }
+       TALLOC_FREE(mutex);
 
        if (!NT_STATUS_IS_OK(sret)) {
                data_blob_free(&auth_data);