r13657: Let winbindd try to obtain the gecos field from the msSFU30Gecos

[Samba/bb.git] / source3 / nsswitch / winbindd_ads.c

/*
   Unix SMB/CIFS implementation.

   Winbind ADS backend functions

   Copyright (C) Andrew Tridgell 2001
   Copyright (C) Andrew Bartlett <abartlet@samba.org> 2003
   Copyright (C) Gerald (Jerry) Carter 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"
#include "winbindd.h"

#ifdef HAVE_ADS

#undef DBGC_CLASS
#define DBGC_CLASS DBGC_WINBIND

/*
  return our ads connections structure for a domain. We keep the connection
  open to make things faster
*/
static ADS_STRUCT *ads_cached_connection(struct winbindd_domain *domain)
{
        ADS_STRUCT *ads;
        ADS_STATUS status;

        if (domain->private_data) {
                ads = (ADS_STRUCT *)domain->private_data;

                /* check for a valid structure */

                DEBUG(7, ("Current tickets expire at %d, time is now %d\n",
                          (uint32) ads->auth.expire, (uint32) time(NULL)));
                if ( ads->config.realm && (ads->auth.expire > time(NULL))) {
                        return ads;
                }
                else {
                        /* we own this ADS_STRUCT so make sure it goes away */
                        ads->is_mine = True;
                        ads_destroy( &ads );
                        ads_kdestroy("MEMORY:winbind_ccache");
                        domain->private_data = NULL;
                }       
        }

        /* we don't want this to affect the users ccache */
        setenv("KRB5CCNAME", "MEMORY:winbind_ccache", 1);

        ads = ads_init(domain->alt_name, domain->name, NULL);
        if (!ads) {
                DEBUG(1,("ads_init for domain %s failed\n", domain->name));
                return NULL;
        }

        /* the machine acct password might have change - fetch it every time */

        SAFE_FREE(ads->auth.password);
        SAFE_FREE(ads->auth.realm);

        if ( IS_DC ) {
                DOM_SID sid;
                time_t last_set_time;

                if ( !secrets_fetch_trusted_domain_password( domain->name, &ads->auth.password, &sid, &last_set_time ) ) {
                        ads_destroy( &ads );
                        return NULL;
                }
                ads->auth.realm = SMB_STRDUP( ads->server.realm );
                strupper_m( ads->auth.realm );
        }
        else {
                struct winbindd_domain *our_domain = domain;

                ads->auth.password = secrets_fetch_machine_password(lp_workgroup(), NULL, NULL);

                /* always give preference to the alt_name in our 
                   primary domain if possible */

                if ( !domain->primary )
                        our_domain = find_our_domain();

                if ( our_domain->alt_name[0] != '\0' ) {
                        ads->auth.realm = SMB_STRDUP( our_domain->alt_name );
                        strupper_m( ads->auth.realm );
                }
                else
                        ads->auth.realm = SMB_STRDUP( lp_realm() );
        }

        ads->auth.renewable = 1;

        status = ads_connect(ads);
        if (!ADS_ERR_OK(status) || !ads->config.realm) {
                extern struct winbindd_methods msrpc_methods, cache_methods;
                DEBUG(1,("ads_connect for domain %s failed: %s\n", 
                         domain->name, ads_errstr(status)));
                ads_destroy(&ads);

                /* if we get ECONNREFUSED then it might be a NT4
                   server, fall back to MSRPC */
                if (status.error_type == ENUM_ADS_ERROR_SYSTEM &&
                    status.err.rc == ECONNREFUSED) {
                        DEBUG(1,("Trying MSRPC methods\n"));
                        if (domain->methods == &cache_methods) {
                                domain->backend = &msrpc_methods;
                        } else {
                                domain->methods = &msrpc_methods;
                        }
                }
                return NULL;
        }

        if (use_nss_info("sfu") && (!ads_check_sfu_mapping(ads))) {
                DEBUG(0,("ads_cached_connection: failed to check sfu attributes\n"));
                return NULL;
        }
        
        /* set the flag that says we don't own the memory even 
           though we do so that ads_destroy() won't destroy the 
           structure we pass back by reference */

        ads->is_mine = False;

        domain->private_data = (void *)ads;
        return ads;
}


/* Query display info for a realm. This is the basic user list fn */
static NTSTATUS query_user_list(struct winbindd_domain *domain,
                               TALLOC_CTX *mem_ctx,
                               uint32 *num_entries, 
                               WINBIND_USERINFO **info)
{
        ADS_STRUCT *ads = NULL;
        const char *attrs[] = {"userPrincipalName",
                               "sAMAccountName",
                               "name", "objectSid", "primaryGroupID", 
                               "sAMAccountType", 
                               ADS_ATTR_SFU_HOMEDIR_OID, 
                               ADS_ATTR_SFU_SHELL_OID,
                               ADS_ATTR_SFU_GECOS_OID,
                               NULL};
        int i, count;
        ADS_STATUS rc;
        void *res = NULL;
        void *msg = NULL;
        NTSTATUS status = NT_STATUS_UNSUCCESSFUL;

        *num_entries = 0;

        DEBUG(3,("ads: query_user_list\n"));

        ads = ads_cached_connection(domain);
        
        if (!ads) {
                domain->last_status = NT_STATUS_SERVER_DISABLED;
                goto done;
        }

        rc = ads_search_retry(ads, &res, "(objectClass=user)", attrs);
        if (!ADS_ERR_OK(rc) || !res) {
                DEBUG(1,("query_user_list ads_search: %s\n", ads_errstr(rc)));
                goto done;
        }

        count = ads_count_replies(ads, res);
        if (count == 0) {
                DEBUG(1,("query_user_list: No users found\n"));
                goto done;
        }

        (*info) = TALLOC_ZERO_ARRAY(mem_ctx, WINBIND_USERINFO, count);
        if (!*info) {
                status = NT_STATUS_NO_MEMORY;
                goto done;
        }

        i = 0;

        for (msg = ads_first_entry(ads, res); msg; msg = ads_next_entry(ads, msg)) {
                char *name, *gecos = NULL;
                char *homedir = NULL;
                char *shell = NULL;
                uint32 group;
                uint32 atype;

                if (!ads_pull_uint32(ads, msg, "sAMAccountType", &atype) ||
                    ads_atype_map(atype) != SID_NAME_USER) {
                        DEBUG(1,("Not a user account? atype=0x%x\n", atype));
                        continue;
                }

                name = ads_pull_username(ads, mem_ctx, msg);

                if (use_nss_info("sfu")) {
                        homedir = ads_pull_string(ads, mem_ctx, msg, 
                                                  ads->schema.sfu_homedir_attr);
                        shell   = ads_pull_string(ads, mem_ctx, msg, 
                                                  ads->schema.sfu_shell_attr);
                        gecos   = ads_pull_string(ads, mem_ctx, msg, 
                                                  ads->schema.sfu_gecos_attr);
                }

                if (gecos == NULL) {
                        gecos = ads_pull_string(ads, mem_ctx, msg, "name");
                }
        
                if (!ads_pull_sid(ads, msg, "objectSid",
                                  &(*info)[i].user_sid)) {
                        DEBUG(1,("No sid for %s !?\n", name));
                        continue;
                }
                if (!ads_pull_uint32(ads, msg, "primaryGroupID", &group)) {
                        DEBUG(1,("No primary group for %s !?\n", name));
                        continue;
                }

                (*info)[i].acct_name = name;
                (*info)[i].full_name = gecos;
                (*info)[i].homedir = homedir;
                (*info)[i].shell = shell;
                sid_compose(&(*info)[i].group_sid, &domain->sid, group);
                i++;
        }

        (*num_entries) = i;
        status = NT_STATUS_OK;

        DEBUG(3,("ads query_user_list gave %d entries\n", (*num_entries)));

done:
        if (res) 
                ads_msgfree(ads, res);

        return status;
}

/* list all domain groups */
static NTSTATUS enum_dom_groups(struct winbindd_domain *domain,
                                TALLOC_CTX *mem_ctx,
                                uint32 *num_entries, 
                                struct acct_info **info)
{
        ADS_STRUCT *ads = NULL;
        const char *attrs[] = {"userPrincipalName", "sAMAccountName",
                               "name", "objectSid", NULL};
        int i, count;
        ADS_STATUS rc;
        void *res = NULL;
        void *msg = NULL;
        NTSTATUS status = NT_STATUS_UNSUCCESSFUL;
        const char *filter;
        BOOL enum_dom_local_groups = False;

        *num_entries = 0;

        DEBUG(3,("ads: enum_dom_groups\n"));

        /* only grab domain local groups for our domain */
        if ( domain->native_mode && strequal(lp_realm(), domain->alt_name)  ) {
                enum_dom_local_groups = True;
        }

        /* Workaround ADS LDAP bug present in MS W2K3 SP0 and W2K SP4 w/o
         * rollup-fixes:
         *
         * According to Section 5.1(4) of RFC 2251 if a value of a type is it's
         * default value, it MUST be absent. In case of extensible matching the
         * "dnattr" boolean defaults to FALSE and so it must be only be present
         * when set to TRUE. 
         *
         * When it is set to FALSE and the OpenLDAP lib (correctly) encodes a
         * filter using bitwise matching rule then the buggy AD fails to decode
         * the extensible match. As a workaround set it to TRUE and thereby add
         * the dnAttributes "dn" field to cope with those older AD versions.
         * It should not harm and won't put any additional load on the AD since
         * none of the dn components have a bitmask-attribute.
         *
         * Thanks to Ralf Haferkamp for input and testing - Guenther */

        filter = talloc_asprintf(mem_ctx, "(&(objectCategory=group)(&(groupType:dn:%s:=%d)(!(groupType:dn:%s:=%d))))", 
                                 ADS_LDAP_MATCHING_RULE_BIT_AND, GROUP_TYPE_SECURITY_ENABLED,
                                 ADS_LDAP_MATCHING_RULE_BIT_AND, 
                                 enum_dom_local_groups ? GROUP_TYPE_BUILTIN_LOCAL_GROUP : GROUP_TYPE_RESOURCE_GROUP);

        if (filter == NULL) {
                status = NT_STATUS_NO_MEMORY;
                goto done;
        }

        ads = ads_cached_connection(domain);

        if (!ads) {
                domain->last_status = NT_STATUS_SERVER_DISABLED;
                goto done;
        }

        rc = ads_search_retry(ads, &res, filter, attrs);
        if (!ADS_ERR_OK(rc) || !res) {
                DEBUG(1,("enum_dom_groups ads_search: %s\n", ads_errstr(rc)));
                goto done;
        }

        count = ads_count_replies(ads, res);
        if (count == 0) {
                DEBUG(1,("enum_dom_groups: No groups found\n"));
                goto done;
        }

        (*info) = TALLOC_ZERO_ARRAY(mem_ctx, struct acct_info, count);
        if (!*info) {
                status = NT_STATUS_NO_MEMORY;
                goto done;
        }

        i = 0;
        
        for (msg = ads_first_entry(ads, res); msg; msg = ads_next_entry(ads, msg)) {
                char *name, *gecos;
                DOM_SID sid;
                uint32 rid;

                name = ads_pull_username(ads, mem_ctx, msg);
                gecos = ads_pull_string(ads, mem_ctx, msg, "name");
                if (!ads_pull_sid(ads, msg, "objectSid", &sid)) {
                        DEBUG(1,("No sid for %s !?\n", name));
                        continue;
                }

                if (!sid_peek_check_rid(&domain->sid, &sid, &rid)) {
                        DEBUG(1,("No rid for %s !?\n", name));
                        continue;
                }

                fstrcpy((*info)[i].acct_name, name);
                fstrcpy((*info)[i].acct_desc, gecos);
                (*info)[i].rid = rid;
                i++;
        }

        (*num_entries) = i;

        status = NT_STATUS_OK;

        DEBUG(3,("ads enum_dom_groups gave %d entries\n", (*num_entries)));

done:
        if (res) 
                ads_msgfree(ads, res);

        return status;
}

/* list all domain local groups */
static NTSTATUS enum_local_groups(struct winbindd_domain *domain,
                                TALLOC_CTX *mem_ctx,
                                uint32 *num_entries, 
                                struct acct_info **info)
{
        /*
         * This is a stub function only as we returned the domain 
         * local groups in enum_dom_groups() if the domain->native field
         * was true.  This is a simple performance optimization when
         * using LDAP.
         *
         * if we ever need to enumerate domain local groups separately, 
         * then this the optimization in enum_dom_groups() will need 
         * to be split out
         */
        *num_entries = 0;
        
        return NT_STATUS_OK;
}

/* convert a DN to a name, SID and name type 
   this might become a major speed bottleneck if groups have
   lots of users, in which case we could cache the results
*/
static BOOL dn_lookup(ADS_STRUCT *ads, TALLOC_CTX *mem_ctx,
                      const char *dn,
                      char **name, uint32 *name_type, DOM_SID *sid)
{
        void *res = NULL;
        const char *attrs[] = {"userPrincipalName", "sAMAccountName",
                               "objectSid", "sAMAccountType", NULL};
        ADS_STATUS rc;
        uint32 atype;
        DEBUG(3,("ads: dn_lookup\n"));

        rc = ads_search_retry_dn(ads, &res, dn, attrs);

        if (!ADS_ERR_OK(rc) || !res) {
                goto failed;
        }

        (*name) = ads_pull_username(ads, mem_ctx, res);

        if (!ads_pull_uint32(ads, res, "sAMAccountType", &atype)) {
                goto failed;
        }
        (*name_type) = ads_atype_map(atype);

        if (!ads_pull_sid(ads, res, "objectSid", sid)) {
                goto failed;
        }

        if (res) 
                ads_msgfree(ads, res);

        return True;

failed:
        if (res) 
                ads_msgfree(ads, res);

        return False;
}

/* Lookup user information from a rid */
static NTSTATUS query_user(struct winbindd_domain *domain, 
                           TALLOC_CTX *mem_ctx, 
                           const DOM_SID *sid, 
                           WINBIND_USERINFO *info)
{
        ADS_STRUCT *ads = NULL;
        const char *attrs[] = {"userPrincipalName", 
                               "sAMAccountName",
                               "name", 
                               "primaryGroupID", 
                               ADS_ATTR_SFU_HOMEDIR_OID, 
                               ADS_ATTR_SFU_SHELL_OID,
                               ADS_ATTR_SFU_GECOS_OID,
                               NULL};
        ADS_STATUS rc;
        int count;
        void *msg = NULL;
        char *ldap_exp;
        char *sidstr;
        uint32 group_rid;
        NTSTATUS status = NT_STATUS_UNSUCCESSFUL;

        DEBUG(3,("ads: query_user\n"));

        ads = ads_cached_connection(domain);
        
        if (!ads) {
                domain->last_status = NT_STATUS_SERVER_DISABLED;
                goto done;
        }

        sidstr = sid_binstring(sid);
        asprintf(&ldap_exp, "(objectSid=%s)", sidstr);
        rc = ads_search_retry(ads, &msg, ldap_exp, attrs);
        free(ldap_exp);
        free(sidstr);
        if (!ADS_ERR_OK(rc) || !msg) {
                DEBUG(1,("query_user(sid=%s) ads_search: %s\n",
                         sid_string_static(sid), ads_errstr(rc)));
                goto done;
        }

        count = ads_count_replies(ads, msg);
        if (count != 1) {
                DEBUG(1,("query_user(sid=%s): Not found\n",
                         sid_string_static(sid)));
                goto done;
        }

        info->acct_name = ads_pull_username(ads, mem_ctx, msg);

        if (use_nss_info("sfu")) {
                info->homedir   = ads_pull_string(ads, mem_ctx, msg, 
                                                  ads->schema.sfu_homedir_attr);
                info->shell     = ads_pull_string(ads, mem_ctx, msg, 
                                                  ads->schema.sfu_shell_attr);
                info->full_name = ads_pull_string(ads, mem_ctx, msg,
                                                  ads->schema.sfu_gecos_attr);
        }

        if (info->full_name == NULL) {
                info->full_name = ads_pull_string(ads, mem_ctx, msg, "name");
        }

        if (!ads_pull_uint32(ads, msg, "primaryGroupID", &group_rid)) {
                DEBUG(1,("No primary group for %s !?\n",
                         sid_string_static(sid)));
                goto done;
        }

        sid_copy(&info->user_sid, sid);
        sid_compose(&info->group_sid, &domain->sid, group_rid);

        status = NT_STATUS_OK;

        DEBUG(3,("ads query_user gave %s\n", info->acct_name));
done:
        if (msg) 
                ads_msgfree(ads, msg);

        return status;
}

/* Lookup groups a user is a member of - alternate method, for when
   tokenGroups are not available. */
static NTSTATUS lookup_usergroups_alt(struct winbindd_domain *domain,
                                      TALLOC_CTX *mem_ctx,
                                      const char *user_dn, 
                                      DOM_SID *primary_group,
                                      size_t *p_num_groups, DOM_SID **user_sids)
{
        ADS_STATUS rc;
        NTSTATUS status = NT_STATUS_UNSUCCESSFUL;
        int count;
        void *res = NULL;
        void *msg = NULL;
        char *ldap_exp;
        ADS_STRUCT *ads;
        const char *group_attrs[] = {"objectSid", NULL};
        char *escaped_dn;
        size_t num_groups = 0;

        DEBUG(3,("ads: lookup_usergroups_alt\n"));

        ads = ads_cached_connection(domain);

        if (!ads) {
                domain->last_status = NT_STATUS_SERVER_DISABLED;
                goto done;
        }

        if (!(escaped_dn = escape_ldap_string_alloc(user_dn))) {
                status = NT_STATUS_NO_MEMORY;
                goto done;
        }

        /* buggy server, no tokenGroups.  Instead lookup what groups this user
           is a member of by DN search on member*/

        if (!(ldap_exp = talloc_asprintf(mem_ctx, "(&(member=%s)(objectClass=group))", escaped_dn))) {
                DEBUG(1,("lookup_usergroups(dn=%s) asprintf failed!\n", user_dn));
                SAFE_FREE(escaped_dn);
                status = NT_STATUS_NO_MEMORY;
                goto done;
        }

        SAFE_FREE(escaped_dn);

        rc = ads_search_retry(ads, &res, ldap_exp, group_attrs);
        
        if (!ADS_ERR_OK(rc) || !res) {
                DEBUG(1,("lookup_usergroups ads_search member=%s: %s\n", user_dn, ads_errstr(rc)));
                return ads_ntstatus(rc);
        }
        
        count = ads_count_replies(ads, res);
        
        *user_sids = NULL;
        num_groups = 0;

        /* always add the primary group to the sid array */
        add_sid_to_array(mem_ctx, primary_group, user_sids, &num_groups);

        if (count > 0) {
                for (msg = ads_first_entry(ads, res); msg;
                     msg = ads_next_entry(ads, msg)) {
                        DOM_SID group_sid;
                
                        if (!ads_pull_sid(ads, msg, "objectSid", &group_sid)) {
                                DEBUG(1,("No sid for this group ?!?\n"));
                                continue;
                        }

                        add_sid_to_array(mem_ctx, &group_sid, user_sids,
                                         &num_groups);
                }

        }

        *p_num_groups = num_groups;
        status = (user_sids != NULL) ? NT_STATUS_OK : NT_STATUS_NO_MEMORY;

        DEBUG(3,("ads lookup_usergroups (alt) for dn=%s\n", user_dn));
done:
        if (res) 
                ads_msgfree(ads, res);

        return status;
}

/* Lookup groups a user is a member of. */
static NTSTATUS lookup_usergroups(struct winbindd_domain *domain,
                                  TALLOC_CTX *mem_ctx,
                                  const DOM_SID *sid, 
                                  uint32 *p_num_groups, DOM_SID **user_sids)
{
        ADS_STRUCT *ads = NULL;
        const char *attrs[] = {"tokenGroups", "primaryGroupID", NULL};
        ADS_STATUS rc;
        int count;
        LDAPMessage *msg = NULL;
        char *user_dn;
        DOM_SID *sids;
        int i;
        DOM_SID primary_group;
        uint32 primary_group_rid;
        fstring sid_string;
        NTSTATUS status = NT_STATUS_UNSUCCESSFUL;
        size_t num_groups = 0;

        DEBUG(3,("ads: lookup_usergroups\n"));
        *p_num_groups = 0;

        ads = ads_cached_connection(domain);
        
        if (!ads) {
                domain->last_status = NT_STATUS_SERVER_DISABLED;
                status = NT_STATUS_SERVER_DISABLED;
                goto done;
        }

        rc = ads_sid_to_dn(ads, mem_ctx, sid, &user_dn);
        if (!ADS_ERR_OK(rc)) {
                status = ads_ntstatus(rc);
                goto done;
        }

        rc = ads_search_retry_dn(ads, (void**)(void *)&msg, user_dn, attrs);
        if (!ADS_ERR_OK(rc)) {
                status = ads_ntstatus(rc);
                DEBUG(1,("lookup_usergroups(sid=%s) ads_search tokenGroups: %s\n", 
                         sid_to_string(sid_string, sid), ads_errstr(rc)));
                goto done;
        }
        
        if (!msg) {
                DEBUG(1,("lookup_usergroups(sid=%s) ads_search tokenGroups: NULL msg\n", 
                         sid_to_string(sid_string, sid)));
                status = NT_STATUS_UNSUCCESSFUL;
                goto done;
        }

        if (!ads_pull_uint32(ads, msg, "primaryGroupID", &primary_group_rid)) {
                DEBUG(1,("%s: No primary group for sid=%s !?\n", 
                         domain->name, sid_to_string(sid_string, sid)));
                goto done;
        }

        sid_copy(&primary_group, &domain->sid);
        sid_append_rid(&primary_group, primary_group_rid);

        count = ads_pull_sids(ads, mem_ctx, msg, "tokenGroups", &sids);

        if (msg) 
                ads_msgfree(ads, msg);

        /* there must always be at least one group in the token, 
           unless we are talking to a buggy Win2k server */
        if (count == 0) {
                status = lookup_usergroups_alt(domain, mem_ctx, user_dn, 
                                             &primary_group,
                                             &num_groups, user_sids);
                *p_num_groups = (uint32)num_groups;
                return status;
        }

        *user_sids = NULL;
        num_groups = 0;

        add_sid_to_array(mem_ctx, &primary_group, user_sids, &num_groups);
        
        for (i=0;i<count;i++) {

                /* ignore Builtin groups from ADS - Guenther */
                if (sid_check_is_in_builtin(&sids[i])) {
                        continue;
                }
                               
                add_sid_to_array_unique(mem_ctx, &sids[i],
                                        user_sids, &num_groups);
        }

        *p_num_groups = (uint32)num_groups;
        status = (user_sids != NULL) ? NT_STATUS_OK : NT_STATUS_NO_MEMORY;

        DEBUG(3,("ads lookup_usergroups for sid=%s\n",
                 sid_to_string(sid_string, sid)));
done:
        return status;
}

/*
  find the members of a group, given a group rid and domain
 */
static NTSTATUS lookup_groupmem(struct winbindd_domain *domain,
                                TALLOC_CTX *mem_ctx,
                                const DOM_SID *group_sid, uint32 *num_names, 
                                DOM_SID **sid_mem, char ***names, 
                                uint32 **name_types)
{
        ADS_STATUS rc;
        int count;
        void *res=NULL;
        ADS_STRUCT *ads = NULL;
        char *ldap_exp;
        NTSTATUS status = NT_STATUS_UNSUCCESSFUL;
        char *sidstr;
        char **members;
        int i;
        size_t num_members;
        fstring sid_string;
        BOOL more_values;
        const char **attrs;
        uint32 first_usn;
        uint32 current_usn;
        int num_retries = 0;

        DEBUG(10,("ads: lookup_groupmem %s sid=%s\n", domain->name, 
                  sid_string_static(group_sid)));

        *num_names = 0;

        ads = ads_cached_connection(domain);
        
        if (!ads) {
                domain->last_status = NT_STATUS_SERVER_DISABLED;
                goto done;
        }

        sidstr = sid_binstring(group_sid);

        /* search for all members of the group */
        if (!(ldap_exp = talloc_asprintf(mem_ctx, "(objectSid=%s)",sidstr))) {
                SAFE_FREE(sidstr);
                DEBUG(1, ("ads: lookup_groupmem: tallloc_asprintf for ldap_exp failed!\n"));
                status = NT_STATUS_NO_MEMORY;
                goto done;
        }
        SAFE_FREE(sidstr);

        members = NULL;
        num_members = 0;

        attrs = TALLOC_ARRAY(mem_ctx, const char *, 3);
        attrs[1] = talloc_strdup(mem_ctx, "usnChanged");
        attrs[2] = NULL;
                
        do {
                if (num_members == 0) 
                        attrs[0] = talloc_strdup(mem_ctx, "member");

                DEBUG(10, ("Searching for attrs[0] = %s, attrs[1] = %s\n", attrs[0], attrs[1]));

                rc = ads_search_retry(ads, &res, ldap_exp, attrs);

                if (!ADS_ERR_OK(rc) || !res) {
                        DEBUG(1,("ads: lookup_groupmem ads_search: %s\n",
                                 ads_errstr(rc)));
                        status = ads_ntstatus(rc);
                        goto done;
                }

                count = ads_count_replies(ads, res);
                if (count == 0)
                        break;

                if (num_members == 0) {
                        if (!ads_pull_uint32(ads, res, "usnChanged", &first_usn)) {
                                DEBUG(1, ("ads: lookup_groupmem could not pull usnChanged!\n"));
                                goto done;
                        }
                }

                if (!ads_pull_uint32(ads, res, "usnChanged", &current_usn)) {
                        DEBUG(1, ("ads: lookup_groupmem could not pull usnChanged!\n"));
                        goto done;
                }

                if (first_usn != current_usn) {
                        DEBUG(5, ("ads: lookup_groupmem USN on this record changed"
                                  " - restarting search\n"));
                        if (num_retries < 5) {
                                num_retries++;
                                num_members = 0;
                                continue;
                        } else {
                                DEBUG(5, ("ads: lookup_groupmem USN on this record changed"
                                          " - restarted search too many times, aborting!\n"));
                                status = NT_STATUS_UNSUCCESSFUL;
                                goto done;
                        }
                }

                members = ads_pull_strings_range(ads, mem_ctx, res,
                                                 "member",
                                                 members,
                                                 &attrs[0],
                                                 &num_members,
                                                 &more_values);

                if ((members == NULL) || (num_members == 0))
                        break;

        } while (more_values);
                
        /* now we need to turn a list of members into rids, names and name types 
           the problem is that the members are in the form of distinguised names
        */

        (*sid_mem) = TALLOC_ZERO_ARRAY(mem_ctx, DOM_SID, num_members);
        (*name_types) = TALLOC_ZERO_ARRAY(mem_ctx, uint32, num_members);
        (*names) = TALLOC_ZERO_ARRAY(mem_ctx, char *, num_members);

        for (i=0;i<num_members;i++) {
                uint32 name_type;
                char *name;
                DOM_SID sid;

                if (dn_lookup(ads, mem_ctx, members[i], &name, &name_type, &sid)) {
                    (*names)[*num_names] = name;
                    (*name_types)[*num_names] = name_type;
                    sid_copy(&(*sid_mem)[*num_names], &sid);
                    (*num_names)++;
                }
        }       

        status = NT_STATUS_OK;
        DEBUG(3,("ads lookup_groupmem for sid=%s\n", sid_to_string(sid_string, group_sid)));
done:

        if (res) 
                ads_msgfree(ads, res);

        return status;
}

/* find the sequence number for a domain */
static NTSTATUS sequence_number(struct winbindd_domain *domain, uint32 *seq)
{
        ADS_STRUCT *ads = NULL;
        ADS_STATUS rc;

        DEBUG(3,("ads: fetch sequence_number for %s\n", domain->name));

        *seq = DOM_SEQUENCE_NONE;

        ads = ads_cached_connection(domain);
        
        if (!ads) {
                domain->last_status = NT_STATUS_SERVER_DISABLED;
                return NT_STATUS_UNSUCCESSFUL;
        }

        rc = ads_USN(ads, seq);
        
        if (!ADS_ERR_OK(rc)) {
        
                /* its a dead connection ; don't destroy it 
                   through since ads_USN() has already done 
                   that indirectly */
                   
                domain->private_data = NULL;
        }
        return ads_ntstatus(rc);
}

/* get a list of trusted domains */
static NTSTATUS trusted_domains(struct winbindd_domain *domain,
                                TALLOC_CTX *mem_ctx,
                                uint32 *num_domains,
                                char ***names,
                                char ***alt_names,
                                DOM_SID **dom_sids)
{
        NTSTATUS                result = NT_STATUS_UNSUCCESSFUL;
        struct ds_domain_trust  *domains = NULL;
        int                     count = 0;
        int                     i;
        uint32                  flags = DS_DOMAIN_DIRECT_OUTBOUND;
        struct rpc_pipe_client *cli;

        DEBUG(3,("ads: trusted_domains\n"));

        *num_domains = 0;
        *alt_names   = NULL;
        *names       = NULL;
        *dom_sids    = NULL;

        result = cm_connect_netlogon(domain, &cli);

        if (!NT_STATUS_IS_OK(result)) {
                DEBUG(5, ("trusted_domains: Could not open a connection to %s "
                          "for PIPE_NETLOGON (%s)\n", 
                          domain->name, nt_errstr(result)));
                return NT_STATUS_UNSUCCESSFUL;
        }
        
        if ( NT_STATUS_IS_OK(result) ) {
                result = rpccli_ds_enum_domain_trusts(cli, mem_ctx,
                                                      cli->cli->desthost, 
                                                      flags, &domains,
                                                      (unsigned int *)&count);
        }
        
        if ( NT_STATUS_IS_OK(result) && count) {
        
                /* Allocate memory for trusted domain names and sids */

                if ( !(*names = TALLOC_ARRAY(mem_ctx, char *, count)) ) {
                        DEBUG(0, ("trusted_domains: out of memory\n"));
                        return NT_STATUS_NO_MEMORY;
                }

                if ( !(*alt_names = TALLOC_ARRAY(mem_ctx, char *, count)) ) {
                        DEBUG(0, ("trusted_domains: out of memory\n"));
                        return NT_STATUS_NO_MEMORY;
                }

                if ( !(*dom_sids = TALLOC_ARRAY(mem_ctx, DOM_SID, count)) ) {
                        DEBUG(0, ("trusted_domains: out of memory\n"));
                        return NT_STATUS_NO_MEMORY;
                }

                /* Copy across names and sids */

                for (i = 0; i < count; i++) {
                        (*names)[i] = domains[i].netbios_domain;
                        (*alt_names)[i] = domains[i].dns_domain;

                        sid_copy(&(*dom_sids)[i], &domains[i].sid);
                }

                *num_domains = count;   
        }

        return result;
}

/* the ADS backend methods are exposed via this structure */
struct winbindd_methods ads_methods = {
        True,
        query_user_list,
        enum_dom_groups,
        enum_local_groups,
        msrpc_name_to_sid,
        msrpc_sid_to_name,
        query_user,
        lookup_usergroups,
        msrpc_lookup_useraliases,
        lookup_groupmem,
        sequence_number,
        msrpc_lockout_policy,
        msrpc_password_policy,
        trusted_domains,
};

#endif