Enhance PAC responder for AD users

This patch modifies the PAC responder so that it can be used with the AD
provider as well. The main difference is that the POSIX UIDs and GIDs
are now lookup up with the help of the SID instead of being calculated
algorithmically. This was necessary because the AD provider allows
either algorithmic mapping or reading the value from attributes stored
in AD.

Fixes https://fedorahosted.org/sssd/ticket/1558

1 files changed, 197 insertions, 740 deletions

diff --git a/src/responder/pac/pacsrv_utils.c b/src/responder/pac/pacsrv_utils.c
index bcea640b..e7e15ac5 100644
--- a/src/responder/pac/pacsrv_utils.c
+++ b/src/responder/pac/pacsrv_utils.c
@@ -25,355 +25,6 @@
 #include "util/util.h"
 #include "responder/pac/pacsrv.h"
 
-static errno_t get_rid(struct dom_sid *sid, uint32_t *rid)
-{
-    if (sid == NULL || sid->num_auths < 1 || rid == NULL) {
-        return EINVAL;
-    }
-
-    *rid = sid->sub_auths[sid->num_auths - 1];
-
-    return EOK;
-}
-
-/**
- * Find the Posix ID to a SID from the local IPA domain
- */
-errno_t local_sid_to_id(struct local_mapping_ranges *map, struct dom_sid *sid,
-                        uint32_t *id)
-{
-    int ret;
-    uint32_t rid;
-
-    if (map == NULL || sid == NULL || id == NULL) {
-        return EINVAL;
-    }
-
-    ret = get_rid(sid, &rid);
-    if (ret != EOK) {
-        DEBUG(SSSDBG_OP_FAILURE, ("get_rid failed.\n"));
-        return ret;
-    }
-
-    if (rid >= map->primary_rids.min && rid <= map->primary_rids.max) {
-        *id = map->local_ids.min + (rid -  map->primary_rids.min);
-    } else if (rid >= map->secondary_rids.min &&
-               rid <= map->secondary_rids.max) {
-        *id = map->local_ids.min + (rid -  map->secondary_rids.min);
-    } else {
-        return ENOENT;
-    }
-
-    if (*id < map->local_ids.min || *id > map->local_ids.max) {
-        return ERANGE;
-    }
-
-    return EOK;
-}
-
-struct sss_domain_info *find_domain_by_id(struct sss_domain_info *domains,
-                                          const char *id_str)
-{
-    struct sss_domain_info *dom;
-    struct sss_domain_info *ret_dom = NULL;
-
-    if (id_str == NULL) {
-        DEBUG(SSSDBG_OP_FAILURE, ("Missing domain id.\n"));
-        return NULL;
-    }
-
-    for (dom = domains; dom; dom = get_next_domain(dom, true)) {
-        if (dom->domain_id == NULL) {
-            continue;
-        }
-
-        if (strcasecmp(dom->domain_id, id_str) == 0) {
-            ret_dom = dom;
-            break;
-        }
-    }
-
-    if (!ret_dom) {
-        DEBUG(SSSDBG_OP_FAILURE, ("No domain with domain ID [%s] found.\n",
-                                  id_str));
-    }
-
-    return ret_dom;
-}
-
-/**
- * Add a new remote domain and the corresponding ID range to the context of
- * the libsss_idmap. Without this it is not possible to find the Posix UID for
- * a user fo the remote domain.
- */
-errno_t add_idmap_domain(struct sss_idmap_ctx *idmap_ctx,
-                         struct sysdb_ctx *sysdb,
-                         const char *domain_name,
-                         const char *dom_sid_str)
-{
-    struct sss_idmap_range range = {0, 0};
-    enum idmap_error_code err;
-    TALLOC_CTX *tmp_ctx = NULL;
-    size_t range_count;
-    struct range_info **range_list;
-    size_t c;
-    int ret;
-
-    if (domain_name == NULL || dom_sid_str == NULL) {
-        DEBUG(SSSDBG_OP_FAILURE, ("Missing domain name or SID.\n"));
-        return EINVAL;
-    }
-
-    tmp_ctx = talloc_new(NULL);
-    if (tmp_ctx == NULL) {
-        DEBUG(SSSDBG_OP_FAILURE, ("talloc_new failed.\n"));
-        return ENOMEM;
-    }
-
-    ret = sysdb_get_ranges(tmp_ctx, sysdb, &range_count, &range_list);
-    if (ret != EOK) {
-        DEBUG(SSSDBG_OP_FAILURE, ("sysdb_get_ranges failed.\n"));
-        goto done;
-    }
-
-    for (c = 0; c < range_count; c++) {
-        if (range_list[c]->trusted_dom_sid != NULL &&
-            strcmp(range_list[c]->trusted_dom_sid, dom_sid_str) == 0) {
-                range.min = range_list[c]->base_id;
-                range.max = range_list[c]->base_id +
-                            range_list[c]->id_range_size - 1;
-                /* TODO: add support for multiple ranges. */
-            break;
-        }
-    }
-
-    if (range.min == 0 && range.max == 0) {
-        DEBUG(SSSDBG_OP_FAILURE, ("Failed to find mapping range for domain "
-                                  "[%s][%s].\n", domain_name, dom_sid_str));
-        ret = ENOENT;
-        goto done;
-    }
-
-    err = sss_idmap_add_domain(idmap_ctx, domain_name, dom_sid_str, &range);
-    if (err != IDMAP_SUCCESS) {
-        DEBUG(SSSDBG_OP_FAILURE, ("sss_idmap_add_domain failed.\n"));
-        return EFAULT;
-    }
-
-    ret = EOK;
-
-done:
-    talloc_free(tmp_ctx);
-    return ret;
-}
-
-/**
- * Find the corresponding UID for a user from a remote domain based on the
- * domain SID of the remote domain and the RID of the user.
- */
-errno_t domsid_rid_to_uid(struct pac_ctx *pac_ctx,
-                          struct sysdb_ctx *sysdb,
-                          const char *domain_name,
-                          struct dom_sid2 *domsid, uint32_t rid,
-                          uid_t *uid)
-{
-    enum idmap_error_code err;
-    char *sid_str = NULL;
-    char *dom_sid_str = NULL;
-    uint32_t id;
-    int ret;
-
-    err = sss_idmap_smb_sid_to_sid(pac_ctx->idmap_ctx, domsid,
-                                   &dom_sid_str);
-    if (err != IDMAP_SUCCESS) {
-        DEBUG(SSSDBG_OP_FAILURE, ("sss_idmap_smb_sid_to_sid failed.\n"));
-        ret = EFAULT;
-        goto done;
-    }
-
-    sid_str = talloc_asprintf(NULL, "%s-%lu", dom_sid_str, (unsigned long) rid);
-    if (sid_str == NULL) {
-        DEBUG(SSSDBG_OP_FAILURE, ("dom_sid_and_rid_string failed.\n"));
-        return ENOMEM;
-    }
-
-    err = sss_idmap_sid_to_unix(pac_ctx->idmap_ctx, sid_str, &id);
-    if (err == IDMAP_NO_DOMAIN) {
-        ret = add_idmap_domain(pac_ctx->idmap_ctx, sysdb, domain_name,
-                               dom_sid_str);
-        if (ret != EOK) {
-            DEBUG(SSSDBG_OP_FAILURE, ("add_idmap_domain failed.\n"));
-            goto done;
-        }
-
-        err = sss_idmap_sid_to_unix(pac_ctx->idmap_ctx, sid_str, &id);
-        if (err != IDMAP_SUCCESS) {
-            DEBUG(SSSDBG_FATAL_FAILURE, ("sss_idmap_sid_to_unix failed "
-                                         "even in the second attempt.\n"));
-            ret = ENOENT;
-            goto done;
-        }
-    } else if (err != IDMAP_SUCCESS && err != IDMAP_NO_DOMAIN) {
-        DEBUG(SSSDBG_OP_FAILURE, ("sss_idmap_sid_to_unix failed.\n"));
-        ret = EFAULT;
-        goto done;
-    }
-
-    *uid = (uid_t) id;
-
-    ret = EOK;
-
-done:
-    talloc_free(dom_sid_str);
-    talloc_free(sid_str);
-    return ret;
-}
-
-/**
- * Return information about the local domain from the main PAC responder
- * context or try to read it from cache and store it in the context.
- */
-errno_t get_parent_domain_data(struct pac_ctx *pac_ctx,
-                               struct sss_domain_info *dom,
-                               struct dom_sid **_sid,
-                               struct local_mapping_ranges **_range_map)
-{
-    struct sysdb_ctx *sysdb;
-    int ret;
-    struct ldb_dn *basedn;
-    const char *attrs[] = {SYSDB_SUBDOMAIN_ID,
-                           NULL};
-    size_t msgs_count;
-    const char *sid_str;
-    struct ldb_message **msgs;
-    TALLOC_CTX *tmp_ctx = NULL;
-    struct dom_sid *sid = NULL;
-    enum idmap_error_code err;
-    size_t range_count;
-    struct range_info **range_list;
-    struct local_mapping_ranges *r_map = NULL;
-    size_t c;
-
-    if (pac_ctx->my_dom_sid == NULL || pac_ctx->range_map == NULL) {
-        sysdb = dom->sysdb;
-
-        if (sysdb == NULL) {
-            DEBUG(SSSDBG_FATAL_FAILURE, ("Missing sysdb context.\n"));
-            ret = EINVAL;
-            goto done;
-        }
-
-        tmp_ctx = talloc_new(NULL);
-        if (tmp_ctx == NULL) {
-            DEBUG(SSSDBG_OP_FAILURE, ("talloc_new failed.\n"));
-            ret = ENOMEM;
-            goto done;
-        }
-
-        /* The data of the parent domain should be read here. */
-        basedn = sysdb_domain_dn(sysdb, tmp_ctx,
-                                 IS_SUBDOMAIN(dom) ? dom->parent : dom);
-        if (basedn == NULL) {
-            ret = ENOMEM;
-            goto done;
-        }
-
-        if (pac_ctx->my_dom_sid == NULL) {
-            ret = sysdb_search_entry(tmp_ctx, sysdb, basedn, LDB_SCOPE_BASE, NULL,
-                                     attrs, &msgs_count, &msgs);
-            if (ret != LDB_SUCCESS) {
-                ret = EIO;
-                goto done;
-            }
-
-            if (msgs_count != 1) {
-                DEBUG(SSSDBG_OP_FAILURE, ("Base search returned [%d] results, "
-                                         "expected 1.\n", msgs_count));
-                ret = EINVAL;
-                goto done;
-            }
-
-            sid_str = ldb_msg_find_attr_as_string(msgs[0], SYSDB_SUBDOMAIN_ID, NULL);
-            if (sid_str == NULL) {
-                DEBUG(SSSDBG_OP_FAILURE, ("SID of my domain is not available.\n"));
-                ret = EINVAL;
-                goto done;
-            }
-
-            err = sss_idmap_sid_to_smb_sid(pac_ctx->idmap_ctx, sid_str, &sid);
-            if (err != IDMAP_SUCCESS) {
-                DEBUG(SSSDBG_OP_FAILURE, ("sss_idmap_sid_to_smb_sid failed.\n"));
-                ret = EFAULT;
-                goto done;
-            }
-
-            pac_ctx->my_dom_sid = talloc_memdup(pac_ctx, sid,
-                                                sizeof(struct dom_sid));
-            if (pac_ctx->my_dom_sid == NULL) {
-                DEBUG(SSSDBG_OP_FAILURE, ("talloc_memdup failed.\n"));
-                ret = ENOMEM;
-                goto done;
-            }
-        }
-
-        if (pac_ctx->range_map == NULL) {
-            ret = sysdb_get_ranges(tmp_ctx, sysdb, &range_count, &range_list);
-            if (ret != EOK) {
-                DEBUG(SSSDBG_OP_FAILURE, ("sysdb_get_ranges failed.\n"));
-                goto done;
-            }
-
-            for (c = 0; c < range_count; c++) {
-                if (range_list[c]->trusted_dom_sid == NULL &&
-                    range_list[c]->secondary_base_rid != 0) {
-                        r_map = talloc_zero(pac_ctx,
-                                            struct local_mapping_ranges);
-                        if (r_map == NULL) {
-                            DEBUG(SSSDBG_OP_FAILURE, ("talloc_zero failed.\n"));
-                            ret = ENOMEM;
-                            goto done;
-                        }
-
-                        r_map->local_ids.min = range_list[c]->base_id;
-                        r_map->local_ids.max = range_list[c]->base_id +
-                                                   range_list[c]->id_range_size - 1;
-
-                        r_map->primary_rids.min = range_list[c]->base_rid;
-                        r_map->primary_rids.max = range_list[c]->base_rid +
-                                                  range_list[c]->id_range_size - 1;
-
-                        r_map->secondary_rids.min = range_list[c]->secondary_base_rid;
-                        r_map->secondary_rids.max = range_list[c]->secondary_base_rid +
-                                                    range_list[c]->id_range_size - 1;
-
-                        /* TODO: add support for multiple ranges. */
-                        break;
-                }
-            }
-
-            if (r_map == NULL) {
-                DEBUG(SSSDBG_OP_FAILURE, ("Failed to find local id map.\n"));
-                ret = ENOENT;
-                goto done;
-            }
-
-            pac_ctx->range_map = r_map;
-         }
-
-    }
-
-    *_sid = pac_ctx->my_dom_sid;
-    *_range_map = pac_ctx->range_map;
-
-    ret = EOK;
-
-done:
-    talloc_free(sid);
-    talloc_free(tmp_ctx);
-
-    return ret;
-}
-
 /**
  * Check if a given SID belongs to a domain identified by the domain SID.
  */
@@ -409,234 +60,167 @@ bool dom_sid_in_domain(const struct dom_sid *domain_sid,
     return true;
 }
 
-
-static errno_t get_dom_grps_from_hash(TALLOC_CTX *mem_ctx,
-                                      hash_table_t *gid_table,
-                                      struct sss_domain_info *grp_dom,
-                                      struct pac_dom_grps *dom_grps)
-{
-    int ret;
-    size_t gid_count;
-    size_t g;
-    struct hash_iter_context_t *iter;
-    hash_entry_t *entry;
-    gid_t *gids = NULL;
-
-    if (grp_dom == NULL) {
-        DEBUG(SSSDBG_OP_FAILURE, ("Missing domain for groups.\n"));
-        return EINVAL;
-    }
-
-    gid_count = hash_count(gid_table);
-    if (gid_count == 0) {
-        DEBUG(SSSDBG_TRACE_FUNC, ("No groups found.\n"));
-        ret = EOK;
-        goto done;
-    }
-
-    gids = talloc_zero_array(mem_ctx, gid_t, gid_count);
-    if (gids == NULL) {
-        DEBUG(SSSDBG_OP_FAILURE, ("talloc_array failed.\n"));
-        ret = ENOMEM;
-        goto done;
-    }
-
-
-    iter = new_hash_iter_context(gid_table);
-    if (iter == NULL) {
-        DEBUG(SSSDBG_OP_FAILURE, ("new_hash_iter_context failed.\n"));
-        ret = EIO;
-        goto done;
-    }
-
-    g = 0;
-    while ((entry = iter->next(iter)) != NULL) {
-        gids[g] = entry->key.ul;
-        g++;
-    }
-
-    if (gid_count != g) {
-        DEBUG(SSSDBG_OP_FAILURE, ("Number of hash entries and groups do not "
-                                  "match.\n"));
-        ret = EINVAL;
-        goto done;
-    }
-
-    ret = EOK;
-
-done:
-    if (ret != EOK) {
-        talloc_free(gids);
-    } else {
-        dom_grps->grp_dom = grp_dom;
-        dom_grps->gid_count = gid_count;
-        dom_grps->gids = gids;
-    }
-
-    return ret;
-}
-
-/**
- * Find all Posix GIDs from a PAC by searching for group SIDs from the local
- * domain and convert them to GIDs.
- */
-errno_t get_gids_from_pac(TALLOC_CTX *mem_ctx,
+errno_t get_sids_from_pac(TALLOC_CTX *mem_ctx,
                           struct pac_ctx *pac_ctx,
-                          struct local_mapping_ranges *range_map,
-                          struct dom_sid *domain_sid,
                           struct PAC_LOGON_INFO *logon_info,
-                          size_t *_gid_count, struct pac_dom_grps **_gids)
+                          char **_user_sid_str,
+                          char **_primary_group_sid_str,
+                          hash_table_t **_sid_table)
 {
     int ret;
-    size_t gid_count = 0;
     size_t s;
     struct netr_SamInfo3 *info3;
-    struct pac_dom_grps *gids = NULL;
-    struct sss_domain_info *grp_dom;
+    struct sss_domain_info *user_dom;
+    struct sss_domain_info *group_dom;
     char *sid_str = NULL;
+    char *user_dom_sid_str = NULL;
+    size_t user_dom_sid_str_len;
     enum idmap_error_code err;
-    struct dom_sid *grp_sid = NULL;
-    uint32_t id;
-    hash_table_t *gid_table;
+    hash_table_t *sid_table = NULL;
     hash_key_t key;
     hash_value_t value;
-    TALLOC_CTX *tmp_ctx = NULL;
+    char *rid_start;
+    struct ldb_result *msg;
+    char *user_sid_str = NULL;
+    char *primary_group_sid_str = NULL;
 
-    if (pac_ctx == NULL || range_map == NULL || domain_sid == NULL ||
-        logon_info == NULL || _gid_count == NULL || _gids == NULL) {
+    if (pac_ctx == NULL || logon_info == NULL || _sid_table == NULL) {
         DEBUG(SSSDBG_OP_FAILURE, ("Missing parameter.\n"));
         return EINVAL;
     }
 
     info3 = &logon_info->info3;
 
-    if (info3->sidcount == 0 && info3->base.groups.count == 0) {
-        DEBUG(SSSDBG_TRACE_ALL, ("No extra groups found.\n"));
-        ret = EOK;
+    ret = sss_hash_create(mem_ctx,
+                          info3->sidcount + info3->base.groups.count + 2,
+                          &sid_table);
+    if (ret != EOK) {
+        DEBUG(SSSDBG_OP_FAILURE, ("sss_hash_create failed.\n"));
         goto done;
     }
 
-    tmp_ctx = talloc_new(NULL);
-    if (tmp_ctx == NULL) {
-        DEBUG(SSSDBG_OP_FAILURE, ("talloc_new failed.\n"));
-        ret = ENOMEM;
+    key.type = HASH_KEY_STRING;
+    value.type = HASH_VALUE_ULONG;
+
+    err = sss_idmap_smb_sid_to_sid(pac_ctx->idmap_ctx, info3->base.domain_sid,
+                                   &user_dom_sid_str);
+    if (err != IDMAP_SUCCESS) {
+        DEBUG(SSSDBG_OP_FAILURE, ("sss_idmap_smb_sid_to_sid failed.\n"));
+        ret = EFAULT;
         goto done;
     }
 
-    /* Currently three group containers are allocated, one for the IPA domain, one
-     * for the trusted AD domain and an empty one to indicate the end of the
-     * list. */
-    gids = talloc_zero_array(tmp_ctx, struct pac_dom_grps, 3);
-    if (gids == NULL) {
-        DEBUG(SSSDBG_OP_FAILURE, ("talloc_zero_array failed.\n"));
-        ret = ENOMEM;
+    ret = responder_get_domain_by_id(pac_ctx->rctx, user_dom_sid_str,
+                                     &user_dom);
+    if (ret != EOK) {
+        DEBUG(SSSDBG_OP_FAILURE, ("responder_get_domain_by_id failed.\n"));
+        ret = EINVAL;
         goto done;
     }
 
-    ret = sss_hash_create(tmp_ctx, info3->sidcount, &gid_table);
-    if (ret != EOK) {
-        DEBUG(SSSDBG_OP_FAILURE, ("sss_hash_create failed.\n"));
+    user_dom_sid_str_len = strlen(user_dom_sid_str);
+    sid_str = talloc_zero_size(mem_ctx, user_dom_sid_str_len + 12);
+    if (sid_str == NULL) {
+        DEBUG(SSSDBG_OP_FAILURE, ("talloc_zero_size failed.\n"));
+        ret = ENOMEM;
         goto done;
     }
+    rid_start = sid_str + user_dom_sid_str_len;
 
-    key.type = HASH_KEY_ULONG;
-    value.type = HASH_VALUE_PTR;
+    memcpy(sid_str, user_dom_sid_str, user_dom_sid_str_len);
 
-    err = sss_idmap_smb_sid_to_sid(pac_ctx->idmap_ctx, domain_sid,
-                                   &sid_str);
-    if (err != IDMAP_SUCCESS) {
-        DEBUG(SSSDBG_OP_FAILURE, ("sss_idmap_smb_sid_to_sid failed.\n"));
-        ret = EFAULT;
+    memset(rid_start, '\0', 12);
+    ret = snprintf(rid_start, 12, "-%lu",
+                                  (unsigned long) info3->base.rid);
+    if (ret < 0 || ret > 12) {
+        DEBUG(SSSDBG_OP_FAILURE, ("snprintf failed.\n"));
+        ret = EIO;
         goto done;
     }
 
-    grp_dom =  find_domain_by_id(pac_ctx->rctx->domains, sid_str);
-    if (grp_dom == NULL) {
-        DEBUG(SSSDBG_OP_FAILURE, ("find_domain_by_id failed.\n"));
-        ret = EINVAL;
+    user_sid_str = talloc_strdup(mem_ctx, sid_str);
+    if (user_sid_str == NULL) {
+        DEBUG(SSSDBG_OP_FAILURE, ("talloc_strdup failed.\n"));
+        ret = ENOMEM;
         goto done;
     }
 
-    for(s = 0; s < info3->sidcount; s++) {
-        if (dom_sid_in_domain(domain_sid, info3->sids[s].sid)) {
-            ret = local_sid_to_id(range_map, info3->sids[s].sid,
-                                  &id);
-            if (ret != EOK) {
-                DEBUG(SSSDBG_OP_FAILURE, ("get_rid failed.\n"));
-                goto done;
-            }
-
-            key.ul = id;
-            value.ptr = grp_dom;
+    key.str = sid_str;
+    value.ul = 0;
 
-            ret = hash_enter(gid_table, &key, &value);
-            if (ret != HASH_SUCCESS) {
-                DEBUG(SSSDBG_OP_FAILURE, ("hash_enter failed [%d][%s].\n",
-                                          ret, hash_error_string(ret)));
-                ret = EIO;
-                goto done;
-            }
-
-            DEBUG(SSSDBG_TRACE_ALL, ("Found extra group with gid [%d].\n", id));
-        }
+    ret = sysdb_search_object_by_sid(mem_ctx, user_dom->sysdb, user_dom,
+                                     sid_str, NULL, &msg);
+    if (ret == EOK && msg->count == 1) {
+        value.ul = ldb_msg_find_attr_as_uint64(msg->msgs[0], SYSDB_UIDNUM, 0);
+        talloc_free(msg);
     }
 
-    ret = get_dom_grps_from_hash(gids, gid_table, grp_dom, &gids[0]);
-    if (ret != EOK) {
-        DEBUG(SSSDBG_OP_FAILURE, ("get_dom_grps_from_hash failed.\n"));
+    ret = hash_enter(sid_table, &key, &value);
+    if (ret != HASH_SUCCESS) {
+        DEBUG(SSSDBG_OP_FAILURE, ("hash_enter failed [%d][%s].\n",
+                                  ret, hash_error_string(ret)));
+        ret = EIO;
         goto done;
     }
-    gid_count += gids[0].gid_count;
 
-    talloc_free(gid_table);
-    ret = sss_hash_create(tmp_ctx, info3->base.groups.count, &gid_table);
-    if (ret != EOK) {
-        DEBUG(SSSDBG_OP_FAILURE, ("sss_hash_create failed.\n"));
+
+    memset(rid_start, '\0', 12);
+    ret = snprintf(rid_start, 12, "-%lu",
+                                  (unsigned long) info3->base.primary_gid);
+    if (ret < 0 || ret > 12) {
+        DEBUG(SSSDBG_OP_FAILURE, ("snprintf failed.\n"));
+        ret = EIO;
         goto done;
     }
 
-    talloc_zfree(sid_str);
-    err = sss_idmap_smb_sid_to_sid(pac_ctx->idmap_ctx, info3->base.domain_sid,
-                                   &sid_str);
-    if (err != IDMAP_SUCCESS) {
-        DEBUG(SSSDBG_OP_FAILURE, ("sss_idmap_smb_sid_to_sid failed.\n"));
-        ret = EFAULT;
+    primary_group_sid_str = talloc_strdup(mem_ctx, sid_str);
+    if (primary_group_sid_str == NULL) {
+        DEBUG(SSSDBG_OP_FAILURE, ("talloc_strdup failed.\n"));
+        ret = ENOMEM;
         goto done;
     }
 
-    grp_dom =  find_domain_by_id(pac_ctx->rctx->domains, sid_str);
-    if (grp_dom == NULL) {
-        DEBUG(SSSDBG_OP_FAILURE, ("find_domain_by_id failed.\n"));
-        ret = EINVAL;
-        goto done;
+    key.str = sid_str;
+    value.ul = 0;
+
+    ret = sysdb_search_object_by_sid(mem_ctx, user_dom->sysdb, user_dom,
+                                     sid_str, NULL, &msg);
+    if (ret == EOK && msg->count == 1) {
+        value.ul = ldb_msg_find_attr_as_uint64(msg->msgs[0], SYSDB_GIDNUM, 0);
+        talloc_free(msg);
     }
 
-    err = sss_idmap_sid_to_smb_sid(pac_ctx->idmap_ctx, sid_str, &grp_sid);
-    if (err != IDMAP_SUCCESS) {
-        DEBUG(SSSDBG_OP_FAILURE, ("sss_idmap_sid_to_smb_sid failed.\n"));
-        ret = EFAULT;
+    ret = hash_enter(sid_table, &key, &value);
+    if (ret != HASH_SUCCESS) {
+        DEBUG(SSSDBG_OP_FAILURE, ("hash_enter failed [%d][%s].\n",
+                                  ret, hash_error_string(ret)));
+        ret = EIO;
         goto done;
     }
 
-    grp_sid->num_auths++;
 
     for (s = 0; s < info3->base.groups.count; s++) {
-        grp_sid->sub_auths[grp_sid->num_auths - 1] =
-                                                info3->base.groups.rids[s].rid;
-        err = sss_idmap_smb_sid_to_unix(pac_ctx->idmap_ctx, grp_sid,
-                                        &id);
-        if (err != IDMAP_SUCCESS) {
-            DEBUG(SSSDBG_FATAL_FAILURE, ("sss_idmap_smb_sid_to_unix failed for"
-                                         "[%s] [%d].\n", sid_str,
-                                         info3->base.groups.rids[s].rid));
-            ret = ENOENT;
+        memset(rid_start, '\0', 12);
+        ret = snprintf(rid_start, 12, "-%lu",
+                                (unsigned long) info3->base.groups.rids[s].rid);
+        if (ret < 0 || ret > 12) {
+            DEBUG(SSSDBG_OP_FAILURE, ("snprintf failed.\n"));
+            ret = EIO;
             goto done;
         }
 
-        key.ul = id;
-        value.ptr = grp_dom;
+        key.str = sid_str;
+        value.ul = 0;
+
+        ret = sysdb_search_object_by_sid(mem_ctx, user_dom->sysdb, user_dom,
+                                         sid_str, NULL, &msg);
+        if (ret == EOK && msg->count == 1) {
+            value.ul = ldb_msg_find_attr_as_uint64(msg->msgs[0],
+                                                   SYSDB_GIDNUM, 0);
+            talloc_free(msg);
+        }
 
-        ret = hash_enter(gid_table, &key, &value);
+        ret = hash_enter(sid_table, &key, &value);
         if (ret != HASH_SUCCESS) {
             DEBUG(SSSDBG_OP_FAILURE, ("hash_enter failed [%d][%s].\n",
                                       ret, hash_error_string(ret)));
@@ -644,29 +228,60 @@ errno_t get_gids_from_pac(TALLOC_CTX *mem_ctx,
             goto done;
         }
 
-        DEBUG(SSSDBG_TRACE_ALL, ("Found extra group with gid [%d].\n", id));
     }
 
-    ret = get_dom_grps_from_hash(gids, gid_table, grp_dom, &gids[1]);
-    if (ret != EOK) {
-        DEBUG(SSSDBG_OP_FAILURE, ("get_dom_grps_from_hash failed.\n"));
-        goto done;
+    talloc_zfree(sid_str);
+
+    for(s = 0; s < info3->sidcount; s++) {
+        err = sss_idmap_smb_sid_to_sid(pac_ctx->idmap_ctx, info3->sids[s].sid,
+                                       &sid_str);
+        if (err != IDMAP_SUCCESS) {
+            DEBUG(SSSDBG_OP_FAILURE, ("sss_idmap_smb_sid_to_sid failed.\n"));
+            ret = EFAULT;
+            goto done;
+        }
+
+        key.str = sid_str;
+        value.ul = 0;
+
+        ret = responder_get_domain_by_id(pac_ctx->rctx, sid_str, &group_dom);
+        if (ret == EOK) {
+            ret = sysdb_search_object_by_sid(mem_ctx, group_dom->sysdb,
+                                             group_dom, sid_str, NULL, &msg);
+            if (ret == EOK && msg->count == 1 ) {
+                value.ul = ldb_msg_find_attr_as_uint64(msg->msgs[0],
+                                                       SYSDB_GIDNUM, 0);
+                talloc_free(msg);
+            }
+        }
+
+        ret = hash_enter(sid_table, &key, &value);
+        if (ret != HASH_SUCCESS) {
+            DEBUG(SSSDBG_OP_FAILURE, ("hash_enter failed [%d][%s].\n",
+                                      ret, hash_error_string(ret)));
+            ret = EIO;
+            goto done;
+        }
+
+        talloc_zfree(sid_str);
     }
-    gid_count += gids[1].gid_count;
 
     ret = EOK;
 
 done:
     talloc_free(sid_str);
-    talloc_free(grp_sid);
+    talloc_free(user_dom_sid_str);
 
     if (ret == EOK) {
-        *_gid_count = gid_count;
-        *_gids = talloc_steal(mem_ctx, gids);
+        *_sid_table = sid_table;
+        *_user_sid_str = user_sid_str;
+        *_primary_group_sid_str = primary_group_sid_str;
+    } else {
+        hash_destroy(sid_table);
+        talloc_free(user_sid_str);
+        talloc_free(primary_group_sid_str);
     }
 
-    talloc_free(tmp_ctx);
-
     return ret;
 }
 
@@ -724,8 +339,10 @@ errno_t get_data_from_pac(TALLOC_CTX *mem_ctx,
  * Fill up the passwd struct with data from the PAC logon info
  */
 errno_t get_pwd_from_pac(TALLOC_CTX *mem_ctx,
-                         struct pac_ctx *pac_ctx,
                          struct sss_domain_info *dom,
+                         char *user_sid_str,
+                         char *primary_group_sid_str,
+                         hash_table_t *sid_table,
                          struct PAC_LOGON_INFO *logon_info,
                          struct passwd **_pwd,
                          struct sysdb_attrs **_attrs)
@@ -737,6 +354,8 @@ errno_t get_pwd_from_pac(TALLOC_CTX *mem_ctx,
     char *lname;
     char *uc_realm;
     char *upn;
+    hash_key_t key;
+    hash_value_t value;
 
     pwd = talloc_zero(mem_ctx, struct passwd);
     if (pwd == NULL) {
@@ -765,22 +384,52 @@ errno_t get_pwd_from_pac(TALLOC_CTX *mem_ctx,
         ret = ENOMEM;
         goto done;
     }
-    pwd->pw_name = sss_tc_fqname(pwd, dom->names, dom, lname);
+
+    /* Subdomain use fully qualified names */
+    if (IS_SUBDOMAIN(dom)) {
+        pwd->pw_name = sss_tc_fqname(pwd, dom->names, dom, lname);
+    } else {
+        pwd->pw_name = talloc_strdup(pwd, lname);
+    }
     if (!pwd->pw_name) {
         DEBUG(SSSDBG_OP_FAILURE, ("talloc_sprintf failed.\n"));
         ret = ENOMEM;
         goto done;
     }
 
-    ret = domsid_rid_to_uid(pac_ctx, dom->sysdb, dom->name,
-                            base_info->domain_sid,
-                            base_info->rid, &pwd->pw_uid);
-    if (ret != EOK) {
-        DEBUG(SSSDBG_OP_FAILURE, ("domsid_rid_to_uid failed.\n"));
+    key.type = HASH_KEY_STRING;
+    key.str = user_sid_str;
+    ret = hash_lookup(sid_table, &key, &value);
+    if (ret != HASH_SUCCESS) {
+        DEBUG(SSSDBG_OP_FAILURE, ("hash_lookup failed.\n"));
+        ret = EIO;
         goto done;
     }
+    if (value.type != HASH_VALUE_ULONG) {
+        DEBUG(SSSDBG_OP_FAILURE, ("Wrong value type.\n"));
+        ret = EIO;
+        goto done;
+    }
+    pwd->pw_uid = value.ul;
 
-    pwd->pw_gid = 0; /* We use MPGs for sub-domains */
+    if (IS_SUBDOMAIN(dom) || dom->mpg) {
+        pwd->pw_gid = 0; /* We use MPGs for sub-domains */
+    } else {
+        key.type = HASH_KEY_STRING;
+        key.str = primary_group_sid_str;
+        ret = hash_lookup(sid_table, &key, &value);
+        if (ret != HASH_SUCCESS) {
+            DEBUG(SSSDBG_OP_FAILURE, ("hash_lookup failed.\n"));
+            ret = EIO;
+            goto done;
+        }
+        if (value.type != HASH_VALUE_ULONG) {
+            DEBUG(SSSDBG_OP_FAILURE, ("Wrong value type.\n"));
+            ret = EIO;
+            goto done;
+        }
+        pwd->pw_gid = value.ul;
+    }
 
     if (base_info->full_name.size != 0) {
         pwd->pw_gecos = talloc_strdup(pwd, base_info->full_name.string);
@@ -794,7 +443,9 @@ errno_t get_pwd_from_pac(TALLOC_CTX *mem_ctx,
                                   "gecos field will by empty.\n "));
     }
 
-    if (dom->subdomain_homedir) {
+    /* Check if there is a special homedir template for sub-domains. If not a
+     * fallback will be added by the NSS responder. */
+    if (IS_SUBDOMAIN(dom) && dom->subdomain_homedir) {
         pwd->pw_dir = expand_homedir_template(pwd, dom->subdomain_homedir,
                                               lname, pwd->pw_uid, NULL,
                                               dom->name, dom->flat_name);
@@ -841,213 +492,22 @@ errno_t get_pwd_from_pac(TALLOC_CTX *mem_ctx,
         goto done;
     }
 
-    *_pwd = pwd;
-    *_attrs = attrs;
-
-    ret = EOK;
-
-done:
+    ret = sysdb_attrs_add_string(attrs, SYSDB_SID_STR, user_sid_str);
     if (ret != EOK) {
-        talloc_free(pwd);
-    }
-
-    return ret;
-}
-
-errno_t diff_gid_lists(TALLOC_CTX *mem_ctx,
-                       size_t cur_grp_num,
-                       struct grp_info *cur_grp_list,
-                       size_t new_gid_num,
-                       struct pac_dom_grps *new_gid_list,
-                       size_t *_add_gid_num,
-                       struct pac_dom_grps **_add_gid_list,
-                       size_t *_del_grp_num,
-                       struct grp_info ***_del_grp_list)
-{
-    int ret;
-    size_t c;
-    size_t g;
-    hash_table_t *table;
-    hash_key_t key;
-    hash_value_t value;
-    size_t add_gid_num = 0;
-    struct pac_dom_grps *add_gid_list = NULL;
-    size_t del_grp_num = 0;
-    struct grp_info **del_grp_list = NULL;
-    TALLOC_CTX *tmp_ctx = NULL;
-    unsigned long value_count;
-    hash_value_t *values;
-    size_t new_dom_num = 0;
-
-    if ((cur_grp_num != 0 && cur_grp_list == NULL) ||
-        (new_gid_num != 0 && new_gid_list == NULL)) {
-        DEBUG(SSSDBG_OP_FAILURE, ("Missing group array.\n"));
-        return EINVAL;
-    }
-
-    if (cur_grp_num == 0 && new_gid_num == 0) {
-        ret = EOK;
-        goto done;
-    }
-
-    tmp_ctx = talloc_new(NULL);
-    if (tmp_ctx == NULL) {
-        DEBUG(SSSDBG_OP_FAILURE, ("talloc_new failed.\n"));
-        ret = ENOMEM;
-        goto done;
-    }
-
-    if (new_gid_num != 0) {
-        for (new_dom_num = 0; new_gid_list[new_dom_num].grp_dom != NULL;
-             new_dom_num++);
-    }
-
-    if (cur_grp_num == 0 && new_gid_num != 0) {
-        add_gid_num = new_gid_num;
-        add_gid_list = talloc_zero_array(tmp_ctx, struct pac_dom_grps,
-                                         new_dom_num + 1);
-        if (add_gid_list == NULL) {
-            DEBUG(SSSDBG_OP_FAILURE, ("talloc_array failed.\n"));
-            ret = ENOMEM;
-            goto done;
-        }
-
-        for (c = 0; c < new_dom_num; c++) {
-            add_gid_list[c].grp_dom = new_gid_list[c].grp_dom;
-            add_gid_list[c].gid_count = new_gid_list[c].gid_count;
-            if (new_gid_list[c].gid_count != 0) {
-                add_gid_list[c].gids = talloc_zero_array(add_gid_list, gid_t,
-                                                     new_gid_list[c].gid_count);
-                if (add_gid_list[c].gids == NULL) {
-                    DEBUG(SSSDBG_OP_FAILURE, ("talloc_zero_array failed.\n"));
-                    ret = ENOMEM;
-                    goto done;
-                }
-
-                for (g = 0; g < new_gid_list[c].gid_count; g++) {
-                    add_gid_list[c].gids[g] = new_gid_list[c].gids[g];
-                }
-            }
-        }
-
-        ret = EOK;
-        goto done;
-    }
-
-    if (cur_grp_num != 0 && new_gid_num == 0) {
-        del_grp_num = cur_grp_num;
-        del_grp_list = talloc_array(tmp_ctx, struct grp_info *, del_grp_num);
-        if (del_grp_list == NULL) {
-            DEBUG(SSSDBG_OP_FAILURE, ("talloc_array failed.\n"));
-            ret = ENOMEM;
-            goto done;
-        }
-
-        for (c = 0; c < del_grp_num; c++) {
-            del_grp_list[c] = &cur_grp_list[c];
-        }
-
-        ret = EOK;
-        goto done;
-    }
-
-    /* Add all current GIDs to a hash and then compare with the new ones in a
-     * single loop */
-    ret = sss_hash_create(tmp_ctx, cur_grp_num, &table);
-    if (ret != EOK) {
-        DEBUG(SSSDBG_OP_FAILURE, ("sss_hash_create failed.\n"));
-        goto done;
-    }
-
-    key.type = HASH_KEY_ULONG;
-    value.type = HASH_VALUE_PTR;
-    for (c = 0; c < cur_grp_num; c++) {
-        key.ul = (unsigned long) cur_grp_list[c].gid;
-        value.ptr = &cur_grp_list[c];
-
-        ret = hash_enter(table, &key, &value);
-        if (ret != HASH_SUCCESS) {
-            DEBUG(SSSDBG_OP_FAILURE, ("hash_enter failed.\n"));
-            ret = EIO;
-            goto done;
-        }
-    }
-
-    add_gid_list = talloc_zero_array(tmp_ctx, struct pac_dom_grps,
-                                     new_dom_num + 1);
-    if (add_gid_list == NULL) {
-        DEBUG(SSSDBG_OP_FAILURE, ("talloc_array failed.\n"));
-        ret = ENOMEM;
-        goto done;
-    }
-
-    for (c = 0; c < new_dom_num; c++) {
-        add_gid_list[c].grp_dom = new_gid_list[c].grp_dom;
-        add_gid_list[c].gid_count = 0;
-
-        for (g = 0; g < new_gid_list[c].gid_count; g++) {
-            key.ul = (unsigned long) new_gid_list[c].gids[g];
-
-            ret = hash_delete(table, &key);
-            if (ret == HASH_ERROR_KEY_NOT_FOUND) {
-                /* gid not found, must be added */
-                add_gid_list[c].gid_count++;
-                add_gid_list[c].gids = talloc_realloc(add_gid_list,
-                                                     add_gid_list,
-                                                     gid_t,
-                                                     add_gid_list[c].gid_count);
-                if (add_gid_list[c].gids == NULL) {
-                    DEBUG(SSSDBG_OP_FAILURE, ("talloc_realloc failed.\n"));
-                    ret = ENOMEM;
-                    goto done;
-                }
-
-                add_gid_list[c].gids[add_gid_list[c].gid_count - 1] =
-                                                        new_gid_list[c].gids[g];
-            } else if (ret != HASH_SUCCESS) {
-                DEBUG(SSSDBG_OP_FAILURE, ("hash_delete failed.\n"));
-                ret = EIO;
-                goto done;
-            }
-        }
-
-        add_gid_num += add_gid_list[c].gid_count;
-    }
-
-    /* the remaining entries in the hash are not in the new list anymore and
-     * must be deleted */
-    ret = hash_values(table, &value_count, &values);
-    if (ret != HASH_SUCCESS) {
-        DEBUG(SSSDBG_OP_FAILURE, ("hash_keys failed.\n"));
-        ret = EIO;
-        goto done;
-    }
-
-    del_grp_num = value_count;
-    del_grp_list = talloc_array(tmp_ctx, struct grp_info *, del_grp_num);
-    if (del_grp_list == NULL) {
-        DEBUG(SSSDBG_OP_FAILURE, ("talloc_array failed.\n"));
-        ret = ENOMEM;
+        DEBUG(SSSDBG_OP_FAILURE, ("sysdb_attrs_add_string failed.\n"));
         goto done;
     }
 
-    for (c = 0; c < del_grp_num; c++) {
-        del_grp_list[c] = (struct grp_info *) values[c].ptr;
-    }
+    *_pwd = pwd;
+    *_attrs = attrs;
 
     ret = EOK;
 
 done:
-
-    if (ret == EOK) {
-        *_add_gid_num = add_gid_num;
-        *_add_gid_list = talloc_steal(mem_ctx, add_gid_list);
-        *_del_grp_num = del_grp_num;
-        *_del_grp_list = talloc_steal(mem_ctx, del_grp_list);
+    if (ret != EOK) {
+        talloc_free(pwd);
     }
 
-    talloc_free(tmp_ctx);
-
     return ret;
 }
 
@@ -1071,14 +531,11 @@ bool new_and_cached_user_differs(struct passwd *pwd, struct ldb_message *msg)
         return true;
     }
 
-    if (!compare_string_with_attr(pwd->pw_name, msg, SYSDB_NAME)) {
+    if (!compare_string_with_attr(pwd->pw_name, msg, SYSDB_NAME) &&
+        !compare_string_with_attr(pwd->pw_name, msg, SYSDB_NAME_ALIAS)) {
         DEBUG(SSSDBG_TRACE_FUNC, ("Names differ."));
         return true;
     }
-    if (!compare_string_with_attr(pwd->pw_gecos, msg, SYSDB_GECOS)) {
-        DEBUG(SSSDBG_TRACE_FUNC, ("Gecos fields differ."));
-        return true;
-    }
 
     if (!compare_string_with_attr(pwd->pw_dir, msg, SYSDB_HOMEDIR)) {
         DEBUG(SSSDBG_TRACE_FUNC, ("Home directories differ."));