r11652: Reinstate the netsamlogon_cache in order to work

around failed query_user calls.  This fixes
logons to a member of a Samba domain as a user from a
trusted AD domain.

As per comments on samba-technical, I still need to add

(a) cache the PAC info as werll as NTLM net_user_info_3
(b) expire the cache when the SMB session goes away

Both Jeremy and Guenther have signed off on the idea.
(This used to be commit 0c2bb5ba7b92d9210e7fa9f7b70aa67dfe9faaf4)

4 files changed, 100 insertions, 0 deletions

diff --git a/source3/nsswitch/winbindd.c b/source3/nsswitch/winbindd.c
index 7f2f3d780e..60a4e2f6c0 100644
--- a/source3/nsswitch/winbindd.c
+++ b/source3/nsswitch/winbindd.c
@@ -1063,6 +1063,8 @@ int main(int argc, char **argv)
 	
 	poptFreeContext(pc);
 
+	netsamlogon_cache_init(); /* Non-critical */
+	
 	init_domain_list();
 
 	init_idmap_child();
diff --git a/source3/nsswitch/winbindd_cache.c b/source3/nsswitch/winbindd_cache.c
index 993e6d96e8..83ded01d4e 100644
--- a/source3/nsswitch/winbindd_cache.c
+++ b/source3/nsswitch/winbindd_cache.c
@@ -1073,6 +1073,18 @@ static NTSTATUS query_user(struct winbindd_domain *domain,
 
 	centry = wcache_fetch(cache, domain, "U/%s", sid_string_static(user_sid));
 	
+	/* If we have an access denied cache entry and a cached info3 in the
+           samlogon cache then do a query.  This will force the rpc back end
+           to return the info3 data. */
+
+	if (NT_STATUS_V(domain->last_status) == NT_STATUS_V(NT_STATUS_ACCESS_DENIED) &&
+	    netsamlogon_cache_have(user_sid)) {
+		DEBUG(10, ("query_user: cached access denied and have cached info3\n"));
+		domain->last_status = NT_STATUS_OK;
+		centry_free(centry);
+		goto do_query;
+	}
+	
 	if (!centry)
 		goto do_query;
 
@@ -1128,6 +1140,18 @@ static NTSTATUS lookup_usergroups(struct winbindd_domain *domain,
 
 	centry = wcache_fetch(cache, domain, "UG/%s", sid_to_string(sid_string, user_sid));
 	
+	/* If we have an access denied cache entry and a cached info3 in the
+           samlogon cache then do a query.  This will force the rpc back end
+           to return the info3 data. */
+
+	if (NT_STATUS_V(domain->last_status) == NT_STATUS_V(NT_STATUS_ACCESS_DENIED) &&
+	    netsamlogon_cache_have(user_sid)) {
+		DEBUG(10, ("query_user: cached access denied and have cached info3\n"));
+		domain->last_status = NT_STATUS_OK;
+		centry_free(centry);
+		goto do_query;
+	}
+	
 	if (!centry)
 		goto do_query;
 
@@ -1401,6 +1425,20 @@ static int traverse_fn(TDB_CONTEXT *the_tdb, TDB_DATA kbuf, TDB_DATA dbuf,
 	return 0;
 }
 
+/* Invalidate the getpwnam and getgroups entries for a winbindd domain */
+
+void wcache_invalidate_samlogon(struct winbindd_domain *domain, 
+				NET_USER_INFO_3 *info3)
+{
+	struct winbind_cache *cache;
+	
+	if (!domain)
+		return;
+
+	cache = get_cache(domain);
+	netsamlogon_clear_cached_user(cache->tdb, info3);
+}
+
 void wcache_invalidate_cache(void)
 {
 	struct winbindd_domain *domain;
diff --git a/source3/nsswitch/winbindd_pam.c b/source3/nsswitch/winbindd_pam.c
index 3571142c58..d398e41468 100644
--- a/source3/nsswitch/winbindd_pam.c
+++ b/source3/nsswitch/winbindd_pam.c
@@ -382,6 +382,9 @@ enum winbindd_result winbindd_dual_pam_auth(struct winbindd_domain *domain,
 	} while ( (attempts < 2) && retry );
 
 	if (NT_STATUS_IS_OK(result)) {
+		netsamlogon_cache_store(state->mem_ctx, name_user, &info3);
+		wcache_invalidate_samlogon(find_domain_from_name(name_domain), &info3);
+
 		/* Check if the user is in the right group */
 
 		if (!NT_STATUS_IS_OK(result = check_info3_in_group(state->mem_ctx, &info3,
@@ -664,6 +667,11 @@ enum winbindd_result winbindd_dual_pam_auth_crap(struct winbindd_domain *domain,
 	} while ( (attempts < 2) && retry );
 
 	if (NT_STATUS_IS_OK(result)) {
+		netsamlogon_cache_store(state->mem_ctx, name_user, &info3);
+		wcache_invalidate_samlogon(find_domain_from_name(name_domain), &info3);
+
+		/* Check if the user is in the right group */
+
 		if (!NT_STATUS_IS_OK(result = check_info3_in_group(state->mem_ctx, &info3,
 							state->request.data.auth_crap.require_membership_of_sid))) {
 			DEBUG(3, ("User %s is not in the required group (%s), so plaintext authentication is rejected\n",
diff --git a/source3/nsswitch/winbindd_rpc.c b/source3/nsswitch/winbindd_rpc.c
index b3bed2e0be..63e2487700 100644
--- a/source3/nsswitch/winbindd_rpc.c
+++ b/source3/nsswitch/winbindd_rpc.c
@@ -329,6 +329,7 @@ static NTSTATUS query_user(struct winbindd_domain *domain,
 	SAM_USERINFO_CTR *ctr;
 	fstring sid_string;
 	uint32 user_rid;
+	NET_USER_INFO_3 *user;
 	struct rpc_pipe_client *cli;
 
 	DEBUG(3,("rpc: query_user rid=%s\n",
@@ -337,6 +338,33 @@ static NTSTATUS query_user(struct winbindd_domain *domain,
 	if (!sid_peek_check_rid(&domain->sid, user_sid, &user_rid))
 		return NT_STATUS_UNSUCCESSFUL;
 	
+	/* try netsamlogon cache first */
+			
+	if ( (user = netsamlogon_cache_get( mem_ctx, user_sid )) != NULL ) 
+	{
+				
+		DEBUG(5,("query_user: Cache lookup succeeded for %s\n", 
+			sid_string_static(user_sid)));
+
+		sid_compose(&user_info->user_sid, &domain->sid, user_rid);
+		sid_compose(&user_info->group_sid, &domain->sid,
+			    user->group_rid);
+				
+		user_info->acct_name = unistr2_tdup(mem_ctx,
+						    &user->uni_user_name);
+		user_info->full_name = unistr2_tdup(mem_ctx,
+						    &user->uni_full_name);
+		
+		user_info->homedir = NULL;
+		user_info->shell = NULL;
+						
+		SAFE_FREE(user);
+				
+		return NT_STATUS_OK;
+	}
+	
+	/* no cache; hit the wire */
+		
 	result = cm_connect_sam(domain, mem_ctx, &cli, &dom_pol);
 	if (!NT_STATUS_IS_OK(result))
 		return result;
@@ -384,6 +412,7 @@ static NTSTATUS lookup_usergroups(struct winbindd_domain *domain,
 	unsigned int i;
 	fstring sid_string;
 	uint32 user_rid;
+	NET_USER_INFO_3 *user;
 	struct rpc_pipe_client *cli;
 
 	DEBUG(3,("rpc: lookup_usergroups sid=%s\n",
@@ -394,6 +423,29 @@ static NTSTATUS lookup_usergroups(struct winbindd_domain *domain,
 
 	*num_groups = 0;
 	*user_grpsids = NULL;
+
+	/* so lets see if we have a cached user_info_3 */
+	
+	if ( (user = netsamlogon_cache_get( mem_ctx, user_sid )) != NULL )
+	{
+		DEBUG(5,("query_user: Cache lookup succeeded for %s\n", 
+			sid_string_static(user_sid)));
+			
+		*num_groups = user->num_groups;
+				
+		(*user_grpsids) = TALLOC_ARRAY(mem_ctx, DOM_SID, *num_groups);
+		for (i=0;i<(*num_groups);i++) {
+			sid_copy(&((*user_grpsids)[i]), &domain->sid);
+			sid_append_rid(&((*user_grpsids)[i]),
+				       user->gids[i].g_rid);
+		}
+				
+		SAFE_FREE(user);
+				
+		return NT_STATUS_OK;
+	}
+
+	/* no cache; hit the wire */
 	
 	result = cm_connect_sam(domain, mem_ctx, &cli, &dom_pol);
 	if (!NT_STATUS_IS_OK(result))