s3-winbind: Fix schannel connections against trusted domain DCs

BUG: https://bugzilla.samba.org/show_bug.cgi?id=11830

Pair-Programmed-With: Andreas Schneider <asn@samba.org>
Signed-off-by: Guenther Deschner <gd@samba.org>
Signed-off-by: Andreas Schneider <asn@samba.org>
Reviewed-by: Alexander Bokovoy <ab@samba.org>

diff --git a/source3/winbindd/winbindd_cm.c b/source3/winbindd/winbindd_cm.c
index ff0e081fb08541bfb0ef0c410e34bbcce386d244..1de731a5ba8314f25739e90f1ce6003c3bd53f8a 100644 (file)
--- a/source3/winbindd/winbindd_cm.c
+++ b/source3/winbindd/winbindd_cm.c
@@ -903,6 +903,7 @@ static NTSTATUS get_trust_credentials(struct winbindd_domain *domain,
        struct cli_credentials *creds;
        NTSTATUS status;
        bool force_machine_account = false;
+       bool ok;
 
        /* If we are a DC and this is not our own domain */
 
@@ -947,7 +948,13 @@ static NTSTATUS get_trust_credentials(struct winbindd_domain *domain,
                                                   CRED_DONT_USE_KERBEROS);
        }
 
-       if (creds_domain != domain) {
+       /*
+        * When we contact our own domain and get a list of the trusted domain
+        * we have the information if we are able to contact the DC with
+        * with our machine account password.
+        */
+       ok = winbindd_can_contact_domain(domain);
+       if (!ok) {
                /*
                 * We can only use schannel against a direct trust
                 */
@@ -3284,6 +3291,8 @@ static NTSTATUS cm_connect_netlogon_transport(struct winbindd_domain *domain,
 
        sec_chan_type = cli_credentials_get_secure_channel_type(creds);
        if (sec_chan_type == SEC_CHAN_NULL) {
+               DBG_WARNING("get_secure_channel_type gave SEC_CHAN_NULL for %s\n",
+                           domain->name);
                return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
        }
 
@@ -3323,6 +3332,11 @@ static NTSTATUS cm_connect_netlogon_transport(struct winbindd_domain *domain,
        conn->netlogon_flags = netlogon_creds->negotiate_flags;
        TALLOC_FREE(netlogon_creds);
 
+       /*
+        * FIXME: Document in which case we are not able to contact
+        * a DC without schannel. Which information do we try to get
+        * from this DC?
+        */
        if (!(conn->netlogon_flags & NETLOGON_NEG_AUTHENTICATED_RPC)) {
                if (lp_winbind_sealed_pipes() || lp_require_strong_key()) {
                        result = NT_STATUS_DOWNGRADE_DETECTED;