Initial import
[samba] / source / libads / kerberos.c
diff --git a/source/libads/kerberos.c b/source/libads/kerberos.c
new file mode 100644 (file)
index 0000000..d5b4b11
--- /dev/null
@@ -0,0 +1,783 @@
+/* 
+   Unix SMB/CIFS implementation.
+   kerberos utility library
+   Copyright (C) Andrew Tridgell 2001
+   Copyright (C) Remus Koos 2001
+   Copyright (C) Nalin Dahyabhai <nalin@redhat.com> 2004.
+   Copyright (C) Jeremy Allison 2004.
+
+   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
+   (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.
+*/
+
+#include "includes.h"
+
+#ifdef HAVE_KRB5
+
+#define LIBADS_CCACHE_NAME "MEMORY:libads"
+
+/*
+  we use a prompter to avoid a crash bug in the kerberos libs when 
+  dealing with empty passwords
+  this prompter is just a string copy ...
+*/
+static krb5_error_code 
+kerb_prompter(krb5_context ctx, void *data,
+              const char *name,
+              const char *banner,
+              int num_prompts,
+              krb5_prompt prompts[])
+{
+       if (num_prompts == 0) return 0;
+
+       memset(prompts[0].reply->data, '\0', prompts[0].reply->length);
+       if (prompts[0].reply->length > 0) {
+               if (data) {
+                       strncpy(prompts[0].reply->data, data, prompts[0].reply->length-1);
+                       prompts[0].reply->length = strlen(prompts[0].reply->data);
+               } else {
+                       prompts[0].reply->length = 0;
+               }
+       }
+       return 0;
+}
+
+/*
+  simulate a kinit, putting the tgt in the given cache location. If cache_name == NULL
+  place in default cache location.
+  remus@snapserver.com
+*/
+int kerberos_kinit_password(const char *principal,
+                               const char *password,
+                               int time_offset,
+                               time_t *expire_time,
+                               const char *cache_name)
+{
+       krb5_context ctx = NULL;
+       krb5_error_code code = 0;
+       krb5_ccache cc = NULL;
+       krb5_principal me;
+       krb5_creds my_creds;
+
+       initialize_krb5_error_table();
+       if ((code = krb5_init_context(&ctx)))
+               return code;
+
+       if (time_offset != 0) {
+               krb5_set_real_time(ctx, time(NULL) + time_offset, 0);
+       }
+       
+       if ((code = krb5_cc_resolve(ctx, cache_name ?
+                       cache_name : krb5_cc_default_name(ctx), &cc))) {
+               krb5_free_context(ctx);
+               return code;
+       }
+       
+       if ((code = krb5_parse_name(ctx, principal, &me))) {
+               krb5_free_context(ctx); 
+               return code;
+       }
+       
+       if ((code = krb5_get_init_creds_password(ctx, &my_creds, me, CONST_DISCARD(char *,password), 
+                                                kerb_prompter, 
+                                                NULL, 0, NULL, NULL))) {
+               krb5_free_principal(ctx, me);
+               krb5_free_context(ctx);         
+               return code;
+       }
+       
+       if ((code = krb5_cc_initialize(ctx, cc, me))) {
+               krb5_free_cred_contents(ctx, &my_creds);
+               krb5_free_principal(ctx, me);
+               krb5_free_context(ctx);         
+               return code;
+       }
+       
+       if ((code = krb5_cc_store_cred(ctx, cc, &my_creds))) {
+               krb5_cc_close(ctx, cc);
+               krb5_free_cred_contents(ctx, &my_creds);
+               krb5_free_principal(ctx, me);
+               krb5_free_context(ctx);         
+               return code;
+       }
+       
+       if (expire_time)
+               *expire_time = (time_t) my_creds.times.endtime;
+
+       krb5_cc_close(ctx, cc);
+       krb5_free_cred_contents(ctx, &my_creds);
+       krb5_free_principal(ctx, me);
+       krb5_free_context(ctx);         
+       
+       return 0;
+}
+
+
+
+/* run kinit to setup our ccache */
+int ads_kinit_password(ADS_STRUCT *ads)
+{
+       char *s;
+       int ret;
+       const char *account_name;
+       fstring acct_name;
+
+       if ( IS_DC ) {
+               /* this will end up getting a ticket for DOMAIN@RUSTED.REA.LM */
+               account_name = lp_workgroup();
+       } else {
+               /* always use the sAMAccountName for security = domain */
+               /* global_myname()$@REA.LM */
+               if ( lp_security() == SEC_DOMAIN ) {
+                       fstr_sprintf( acct_name, "%s$", global_myname() );
+                       account_name = acct_name;
+               }
+               else 
+                       /* This looks like host/global_myname()@REA.LM */
+                       account_name = ads->auth.user_name;
+       }
+
+       if (asprintf(&s, "%s@%s", account_name, ads->auth.realm) == -1) {
+               return KRB5_CC_NOMEM;
+       }
+
+       if (!ads->auth.password) {
+               return KRB5_LIBOS_CANTREADPWD;
+       }
+       
+       ret = kerberos_kinit_password(s, ads->auth.password, ads->auth.time_offset,
+                       &ads->auth.expire, NULL);
+
+       if (ret) {
+               DEBUG(0,("kerberos_kinit_password %s failed: %s\n", 
+                        s, error_message(ret)));
+       }
+       free(s);
+       return ret;
+}
+
+int ads_kdestroy(const char *cc_name)
+{
+       krb5_error_code code;
+       krb5_context ctx = NULL;
+       krb5_ccache cc = NULL;
+
+       initialize_krb5_error_table();
+       if ((code = krb5_init_context (&ctx))) {
+               DEBUG(3, ("ads_kdestroy: kdb5_init_context failed: %s\n", 
+                       error_message(code)));
+               return code;
+       }
+  
+       if (!cc_name) {
+               if ((code = krb5_cc_default(ctx, &cc))) {
+                       krb5_free_context(ctx);
+                       return code;
+               }
+       } else {
+               if ((code = krb5_cc_resolve(ctx, cc_name, &cc))) {
+                       DEBUG(3, ("ads_kdestroy: krb5_cc_resolve failed: %s\n",
+                                 error_message(code)));
+                       krb5_free_context(ctx);
+                       return code;
+               }
+       }
+
+       if ((code = krb5_cc_destroy (ctx, cc))) {
+               DEBUG(3, ("ads_kdestroy: krb5_cc_destroy failed: %s\n", 
+                       error_message(code)));
+       }
+
+       krb5_free_context (ctx);
+       return code;
+}
+
+/************************************************************************
+ Routine to fetch the salting principal for a service.  Active
+ Directory may use a non-obvious principal name to generate the salt
+ when it determines the key to use for encrypting tickets for a service,
+ and hopefully we detected that when we joined the domain.
+ ************************************************************************/
+
+static char *kerberos_secrets_fetch_salting_principal(const char *service, int enctype)
+{
+       char *key = NULL;
+       char *ret = NULL;
+
+       asprintf(&key, "%s/%s/enctype=%d", SECRETS_SALTING_PRINCIPAL, service, enctype);
+       if (!key) {
+               return NULL;
+       }
+       ret = (char *)secrets_fetch(key, NULL);
+       SAFE_FREE(key);
+       return ret;
+}
+
+/************************************************************************
+ Routine to get the salting principal for this service.  Active
+ Directory may use a non-obvious principal name to generate the salt
+ when it determines the key to use for encrypting tickets for a service,
+ and hopefully we detected that when we joined the domain.
+ Caller must free if return is not null.
+ ************************************************************************/
+
+krb5_principal kerberos_fetch_salt_princ_for_host_princ(krb5_context context,
+                                                       krb5_principal host_princ,
+                                                       int enctype)
+{
+       char *unparsed_name = NULL, *salt_princ_s = NULL;
+       krb5_principal ret_princ = NULL;
+
+       if (krb5_unparse_name(context, host_princ, &unparsed_name) != 0) {
+               return (krb5_principal)NULL;
+       }
+
+       if ((salt_princ_s = kerberos_secrets_fetch_salting_principal(unparsed_name, enctype)) == NULL) {
+               krb5_free_unparsed_name(context, unparsed_name);
+               return (krb5_principal)NULL;
+       }
+
+       if (krb5_parse_name(context, salt_princ_s, &ret_princ) != 0) {
+               krb5_free_unparsed_name(context, unparsed_name);
+               SAFE_FREE(salt_princ_s);
+               return (krb5_principal)NULL;
+       }
+       krb5_free_unparsed_name(context, unparsed_name);
+       SAFE_FREE(salt_princ_s);
+       return ret_princ;
+}
+
+/************************************************************************
+ Routine to set the salting principal for this service.  Active
+ Directory may use a non-obvious principal name to generate the salt
+ when it determines the key to use for encrypting tickets for a service,
+ and hopefully we detected that when we joined the domain.
+ Setting principal to NULL deletes this entry.
+ ************************************************************************/
+
+BOOL kerberos_secrets_store_salting_principal(const char *service,
+                                             int enctype,
+                                             const char *principal)
+{
+       char *key = NULL;
+       BOOL ret = False;
+       krb5_context context = NULL;
+       krb5_principal princ = NULL;
+       char *princ_s = NULL;
+       char *unparsed_name = NULL;
+
+       krb5_init_context(&context);
+       if (!context) {
+               return False;
+       }
+       if (strchr_m(service, '@')) {
+               asprintf(&princ_s, "%s", service);
+       } else {
+               asprintf(&princ_s, "%s@%s", service, lp_realm());
+       }
+
+       if (krb5_parse_name(context, princ_s, &princ) != 0) {
+               goto out;
+               
+       }
+       if (krb5_unparse_name(context, princ, &unparsed_name) != 0) {
+               goto out;
+       }
+
+       asprintf(&key, "%s/%s/enctype=%d", SECRETS_SALTING_PRINCIPAL, unparsed_name, enctype);
+       if (!key)  {
+               goto out;
+       }
+
+       if ((principal != NULL) && (strlen(principal) > 0)) {
+               ret = secrets_store(key, principal, strlen(principal) + 1);
+       } else {
+               ret = secrets_delete(key);
+       }
+
+ out:
+
+       SAFE_FREE(key);
+       SAFE_FREE(princ_s);
+
+       if (unparsed_name) {
+               krb5_free_unparsed_name(context, unparsed_name);
+       }
+       if (context) {
+               krb5_free_context(context);
+       }
+
+       return ret;
+}
+
+/************************************************************************
+ Routine to get initial credentials as a service ticket for the local machine.
+ Returns a buffer initialized with krb5_mk_req_extended.
+ ************************************************************************/
+
+static krb5_error_code get_service_ticket(krb5_context ctx,
+                                       krb5_ccache ccache,
+                                       const char *service_principal,
+                                       int enctype,
+                                       krb5_data *p_outbuf)
+{
+       krb5_creds creds, *new_creds = NULL;
+       char *service_s = NULL;
+       char *machine_account = NULL, *password = NULL;
+       krb5_data in_data;
+       krb5_auth_context auth_context = NULL;
+       krb5_error_code err = 0;
+
+       ZERO_STRUCT(creds);
+
+       asprintf(&machine_account, "%s$@%s", global_myname(), lp_realm());
+       if (machine_account == NULL) {
+               goto out;
+       }
+       password = secrets_fetch_machine_password(lp_workgroup(), NULL, NULL);
+       if (password == NULL) {
+               goto out;
+       }
+       if ((err = kerberos_kinit_password(machine_account, password, 0, NULL, LIBADS_CCACHE_NAME)) != 0) {
+               DEBUG(0,("get_service_ticket: kerberos_kinit_password %s@%s failed: %s\n", 
+                       machine_account,
+                       lp_realm(),
+                       error_message(err)));
+               goto out;
+       }
+
+       /* Ok - the above call has gotten a TGT. Now we need to get a service
+          ticket to ourselves. */
+
+       /* Set up the enctype and client and server principal fields for krb5_get_credentials. */
+       kerberos_set_creds_enctype(&creds, enctype);
+
+       if ((err = krb5_cc_get_principal(ctx, ccache, &creds.client))) {
+               DEBUG(3, ("get_service_ticket: krb5_cc_get_principal failed: %s\n", 
+                       error_message(err)));
+               goto out;
+       }
+
+       if (strchr_m(service_principal, '@')) {
+               asprintf(&service_s, "%s", service_principal);
+       } else {
+               asprintf(&service_s, "%s@%s", service_principal, lp_realm());
+       }
+
+       if ((err = krb5_parse_name(ctx, service_s, &creds.server))) {
+               DEBUG(0,("get_service_ticket: krb5_parse_name %s failed: %s\n", 
+                       service_s, error_message(err)));
+               goto out;
+       }
+
+       if ((err = krb5_get_credentials(ctx, 0, ccache, &creds, &new_creds))) {
+               DEBUG(5,("get_service_ticket: krb5_get_credentials for %s enctype %d failed: %s\n", 
+                       service_s, enctype, error_message(err)));
+               goto out;
+       }
+
+       memset(&in_data, '\0', sizeof(in_data));
+       if ((err = krb5_mk_req_extended(ctx, &auth_context, 0, &in_data,
+                       new_creds, p_outbuf)) != 0) {
+               DEBUG(0,("get_service_ticket: krb5_mk_req_extended failed: %s\n", 
+                       error_message(err)));
+               goto out;
+       }
+
+ out:
+
+       if (auth_context) {
+               krb5_auth_con_free(ctx, auth_context);
+       }
+       if (new_creds) {
+               krb5_free_creds(ctx, new_creds);
+       }
+       if (creds.server) {
+               krb5_free_principal(ctx, creds.server);
+       }
+       if (creds.client) {
+               krb5_free_principal(ctx, creds.client);
+       }
+
+       SAFE_FREE(service_s);
+       SAFE_FREE(password);
+       SAFE_FREE(machine_account);
+       return err;
+}
+
+/************************************************************************
+ Check if the machine password can be used in conjunction with the salting_principal
+ to generate a key which will successfully decrypt the AP_REQ already
+ gotten as a message to the local machine.
+ ************************************************************************/
+
+static BOOL verify_service_password(krb5_context ctx,
+                                   int enctype,
+                                   const char *salting_principal,
+                                   krb5_data *in_data)
+{
+       BOOL ret = False;
+       krb5_principal salting_kprinc = NULL;
+       krb5_ticket *ticket = NULL;
+       krb5_keyblock key;
+       krb5_data passdata;
+       char *salting_s = NULL;
+       char *machine_account = NULL, *password = NULL;
+       krb5_auth_context auth_context = NULL;
+       krb5_error_code err;
+
+       memset(&passdata, '\0', sizeof(passdata));
+       memset(&key, '\0', sizeof(key));
+
+       asprintf(&machine_account, "%s$@%s", global_myname(), lp_realm());
+       if (machine_account == NULL) {
+               goto out;
+       }
+       password = secrets_fetch_machine_password(lp_workgroup(), NULL, NULL);
+       if (password == NULL) {
+               goto out;
+       }
+
+       if (strchr_m(salting_principal, '@')) {
+               asprintf(&salting_s, "%s", salting_principal);
+       } else {
+               asprintf(&salting_s, "%s@%s", salting_principal, lp_realm());
+       }
+
+       if ((err = krb5_parse_name(ctx, salting_s, &salting_kprinc))) {
+               DEBUG(0,("verify_service_password: krb5_parse_name %s failed: %s\n", 
+                       salting_s, error_message(err)));
+               goto out;
+       }
+
+       passdata.length = strlen(password);
+       passdata.data = (char*)password;
+       if ((err = create_kerberos_key_from_string_direct(ctx, salting_kprinc, &passdata, &key, enctype))) {
+               DEBUG(0,("verify_service_password: create_kerberos_key_from_string %d failed: %s\n",
+                       enctype, error_message(err)));
+               goto out;
+       }
+
+       if ((err = krb5_auth_con_init(ctx, &auth_context)) != 0) {
+               DEBUG(0,("verify_service_password: krb5_auth_con_init failed %s\n", error_message(err)));
+               goto out;
+       }
+
+       if ((err = krb5_auth_con_setuseruserkey(ctx, auth_context, &key)) != 0) {
+               DEBUG(0,("verify_service_password: krb5_auth_con_setuseruserkey failed %s\n", error_message(err)));
+               goto out;
+       }
+
+       if (!(err = krb5_rd_req(ctx, &auth_context, in_data, NULL, NULL, NULL, &ticket))) {
+               DEBUG(10,("verify_service_password: decrypted message with enctype %u salt %s!\n",
+                               (unsigned int)enctype, salting_s));
+               ret = True;
+       }
+
+ out:
+
+       memset(&passdata, 0, sizeof(passdata));
+       krb5_free_keyblock_contents(ctx, &key);
+       if (ticket != NULL) {
+               krb5_free_ticket(ctx, ticket);
+       }
+       if (salting_kprinc) {
+               krb5_free_principal(ctx, salting_kprinc);
+       }
+       SAFE_FREE(salting_s);
+       SAFE_FREE(password);
+       SAFE_FREE(machine_account);
+       return ret;
+}
+
+/************************************************************************
+ *
+ * From the current draft of kerberos-clarifications:
+ *
+ *     It is not possible to reliably generate a user's key given a pass
+ *     phrase without contacting the KDC, since it will not be known
+ *     whether alternate salt or parameter values are required.
+ *
+ * And because our server has a password, we have this exact problem.  We
+ * make multiple guesses as to which principal name provides the salt which
+ * the KDC is using.
+ *
+ ************************************************************************/
+
+static void kerberos_derive_salting_principal_for_enctype(const char *service_principal,
+                                                         krb5_context ctx,
+                                                         krb5_ccache ccache,
+                                                         krb5_enctype enctype,
+                                                         krb5_enctype *enctypes)
+{
+       char *salting_principals[3] = {NULL, NULL, NULL}, *second_principal = NULL;
+       krb5_error_code err = 0;
+       krb5_data outbuf;
+       int i, j;
+
+       memset(&outbuf, '\0', sizeof(outbuf));
+
+       /* Check that the service_principal is useful. */
+       if ((service_principal == NULL) || (strlen(service_principal) == 0)) {
+               return;
+       }
+
+       /* Generate our first guess -- the principal as-given. */
+       asprintf(&salting_principals[0], "%s", service_principal);
+       if ((salting_principals[0] == NULL) || (strlen(salting_principals[0]) == 0)) {
+               return;
+       }
+
+       /* Generate our second guess -- the computer's principal, as Win2k3. */
+       asprintf(&second_principal, "host/%s.%s", global_myname(), lp_realm());
+       if (second_principal != NULL) {
+               strlower_m(second_principal);
+               asprintf(&salting_principals[1], "%s@%s", second_principal, lp_realm());
+               SAFE_FREE(second_principal);
+       }
+       if ((salting_principals[1] == NULL) || (strlen(salting_principals[1]) == 0)) {
+               goto out;
+       }
+
+       /* Generate our third guess -- the computer's principal, as Win2k. */
+       asprintf(&second_principal, "HOST/%s", global_myname());
+       if (second_principal != NULL) {
+               strlower_m(second_principal + 5);
+               asprintf(&salting_principals[2], "%s@%s",
+                       second_principal, lp_realm());
+               SAFE_FREE(second_principal);
+       }
+       if ((salting_principals[2] == NULL) || (strlen(salting_principals[2]) == 0)) {
+               goto out;
+       }
+
+       /* Get a service ticket for ourselves into our memory ccache. */
+       /* This will commonly fail if there is no principal by that name (and we're trying
+          many names). So don't print a debug 0 error. */
+
+       if ((err = get_service_ticket(ctx, ccache, service_principal, enctype, &outbuf)) != 0) {
+               DEBUG(3, ("verify_service_password: get_service_ticket failed: %s\n", 
+                       error_message(err)));
+               goto out;
+       }
+
+       /* At this point we have a message to ourselves, salted only the KDC knows how. We
+          have to work out what that salting is. */
+
+       /* Try and find the correct salting principal. */
+       for (i = 0; i < sizeof(salting_principals) / sizeof(salting_principals[i]); i++) {
+               if (verify_service_password(ctx, enctype, salting_principals[i], &outbuf)) {
+                       break;
+               }
+       }
+
+       /* If we failed to get a match, return. */
+       if (i >= sizeof(salting_principals) / sizeof(salting_principals[i])) {
+               goto out;
+       }
+
+       /* If we succeeded, store the principal for use for all enctypes which
+        * share the same cipher and string-to-key function.  Doing this here
+        * allows servers which just pass a keytab to krb5_rd_req() to work
+        * correctly. */
+       for (j = 0; enctypes[j] != 0; j++) {
+               if (enctype != enctypes[j]) {
+                       /* If this enctype isn't compatible with the one which
+                        * we used, skip it. */
+
+                       if (!kerberos_compatible_enctypes(ctx, enctypes[j], enctype))
+                               continue;
+               }
+               /* If the principal which gives us the proper salt is the one
+                * which we would normally guess, don't bother noting anything
+                * in the secrets tdb. */
+               if (strcmp(service_principal, salting_principals[i]) != 0) {
+                       kerberos_secrets_store_salting_principal(service_principal,
+                                                               enctypes[j],
+                                                               salting_principals[i]);
+               }
+       }
+
+ out :
+
+       kerberos_free_data_contents(ctx, &outbuf);
+       SAFE_FREE(salting_principals[0]);
+       SAFE_FREE(salting_principals[1]);
+       SAFE_FREE(salting_principals[2]);
+       SAFE_FREE(second_principal);
+}
+
+/************************************************************************
+ Go through all the possible enctypes for this principal.
+ ************************************************************************/
+
+static void kerberos_derive_salting_principal_direct(krb5_context context,
+                                       krb5_ccache ccache,
+                                       krb5_enctype *enctypes,
+                                       char *service_principal)
+{
+       int i;
+
+       /* Try for each enctype separately, because the rules are
+        * different for different enctypes. */
+       for (i = 0; enctypes[i] != 0; i++) {
+               /* Delete secrets entry first. */
+               kerberos_secrets_store_salting_principal(service_principal, 0, NULL);
+#ifdef ENCTYPE_ARCFOUR_HMAC
+               if (enctypes[i] == ENCTYPE_ARCFOUR_HMAC) {
+                       /* Of course this'll always work, so just save
+                        * ourselves the effort. */
+                       continue;
+               }
+#endif
+               /* Try to figure out what's going on with this
+                * principal. */
+               kerberos_derive_salting_principal_for_enctype(service_principal,
+                                                               context,
+                                                               ccache,
+                                                               enctypes[i],
+                                                               enctypes);
+       }
+}
+
+/************************************************************************
+ Wrapper function for the above.
+ ************************************************************************/
+
+BOOL kerberos_derive_salting_principal(char *service_principal)
+{
+       krb5_context context = NULL;
+       krb5_enctype *enctypes = NULL;
+       krb5_ccache ccache = NULL;
+       krb5_error_code ret = 0;
+
+       initialize_krb5_error_table();
+       if ((ret = krb5_init_context(&context)) != 0) {
+               DEBUG(1,("kerberos_derive_cifs_salting_principals: krb5_init_context failed. %s\n",
+                       error_message(ret)));
+               return False;
+       }
+       if ((ret = get_kerberos_allowed_etypes(context, &enctypes)) != 0) {
+               DEBUG(1,("kerberos_derive_cifs_salting_principals: get_kerberos_allowed_etypes failed. %s\n",
+                       error_message(ret)));
+               goto out;
+       }
+
+       if ((ret = krb5_cc_resolve(context, LIBADS_CCACHE_NAME, &ccache)) != 0) {
+               DEBUG(3, ("get_service_ticket: krb5_cc_resolve for %s failed: %s\n", 
+                       LIBADS_CCACHE_NAME, error_message(ret)));
+               goto out;
+       }
+
+       kerberos_derive_salting_principal_direct(context, ccache, enctypes, service_principal);
+
+  out: 
+       if (enctypes) {
+               free_kerberos_etypes(context, enctypes);
+       }
+       if (ccache) {
+               krb5_cc_destroy(context, ccache);
+       }
+       if (context) {
+               krb5_free_context(context);
+       }
+
+       return ret ? False : True;
+}
+
+/************************************************************************
+ Core function to try and determine what salt is being used for any keytab
+ keys.
+ ************************************************************************/
+
+BOOL kerberos_derive_cifs_salting_principals(void)
+{
+       fstring my_fqdn;
+       char *service = NULL;
+       krb5_context context = NULL;
+       krb5_enctype *enctypes = NULL;
+       krb5_ccache ccache = NULL;
+       krb5_error_code ret = 0;
+       BOOL retval = False;
+
+       initialize_krb5_error_table();
+       if ((ret = krb5_init_context(&context)) != 0) {
+               DEBUG(1,("kerberos_derive_cifs_salting_principals: krb5_init_context failed. %s\n",
+                       error_message(ret)));
+               return False;
+       }
+       if ((ret = get_kerberos_allowed_etypes(context, &enctypes)) != 0) {
+               DEBUG(1,("kerberos_derive_cifs_salting_principals: get_kerberos_allowed_etypes failed. %s\n",
+                       error_message(ret)));
+               goto out;
+       }
+
+       if ((ret = krb5_cc_resolve(context, LIBADS_CCACHE_NAME, &ccache)) != 0) {
+               DEBUG(3, ("get_service_ticket: krb5_cc_resolve for %s failed: %s\n", 
+                       LIBADS_CCACHE_NAME, error_message(ret)));
+               goto out;
+       }
+
+       if (asprintf(&service, "%s$", global_myname()) != -1) {
+               strlower_m(service);
+               kerberos_derive_salting_principal_direct(context, ccache, enctypes, service);
+               SAFE_FREE(service);
+       }
+       if (asprintf(&service, "cifs/%s", global_myname()) != -1) {
+               strlower_m(service);
+               kerberos_derive_salting_principal_direct(context, ccache, enctypes, service);
+               SAFE_FREE(service);
+       }
+       if (asprintf(&service, "host/%s", global_myname()) != -1) {
+               strlower_m(service);
+               kerberos_derive_salting_principal_direct(context, ccache, enctypes, service);
+               SAFE_FREE(service);
+       }
+       if (asprintf(&service, "cifs/%s.%s", global_myname(), lp_realm()) != -1) {
+               strlower_m(service);
+               kerberos_derive_salting_principal_direct(context, ccache, enctypes, service);
+               SAFE_FREE(service);
+       }
+       if (asprintf(&service, "host/%s.%s", global_myname(), lp_realm()) != -1) {
+               strlower_m(service);
+               kerberos_derive_salting_principal_direct(context, ccache, enctypes, service);
+               SAFE_FREE(service);
+       }
+       name_to_fqdn(my_fqdn, global_myname());
+       if (asprintf(&service, "cifs/%s", my_fqdn) != -1) {
+               strlower_m(service);
+               kerberos_derive_salting_principal_direct(context, ccache, enctypes, service);
+               SAFE_FREE(service);
+       }
+       if (asprintf(&service, "host/%s", my_fqdn) != -1) {
+               strlower_m(service);
+               kerberos_derive_salting_principal_direct(context, ccache, enctypes, service);
+               SAFE_FREE(service);
+       }
+
+       retval = True;
+
+  out: 
+       if (enctypes) {
+               free_kerberos_etypes(context, enctypes);
+       }
+       if (ccache) {
+               krb5_cc_destroy(context, ccache);
+       }
+       if (context) {
+               krb5_free_context(context);
+       }
+       return retval;
+}
+#endif