s3:rpc_server/netlogon: if we require AES there's no need to remove the ARCFOUR flag

With SAMBA_WEAK_CRYPTO_DISALLOWED we will return DOWNGRADE_DETECTED with negotiate_flags = 0,
if AES was not negotiated...

And if AES was negotiated there's no harm in returning the ARCFOUR
flag...

BUG: https://bugzilla.samba.org/show_bug.cgi?id=15425

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>

diff --git a/source3/rpc_server/netlogon/srv_netlog_nt.c b/source3/rpc_server/netlogon/srv_netlog_nt.c
index f9d3dcca6b078d6eced033912e68e8c2fdcf2fe7..4a258874d16deaca1fd4417720bb8dce70f40080 100644 (file)
--- a/source3/rpc_server/netlogon/srv_netlog_nt.c
+++ b/source3/rpc_server/netlogon/srv_netlog_nt.c
@@ -927,6 +927,18 @@ NTSTATUS _netr_ServerAuthenticate3(struct pipes_struct *p,
                   NETLOGON_NEG_SUPPORTS_AES |
                   NETLOGON_NEG_SCHANNEL;
 
+       /*
+        * With SAMBA_WEAK_CRYPTO_DISALLOWED we will return DOWNGRADE_DETECTED
+        * with negotiate_flags = 0 below, if NETLOGON_NEG_SUPPORTS_AES was not
+        * negotiated...
+        *
+        * And if NETLOGON_NEG_SUPPORTS_AES was negotiated there's no harm in
+        * returning the NETLOGON_NEG_ARCFOUR flag too...
+        *
+        * So there's no reason to remove NETLOGON_NEG_ARCFOUR nor
+        * NETLOGON_NEG_STRONG_KEYS from srv_flgs...
+        */
+
        /*
         * Support authentication of trusted domains.
         *
@@ -940,13 +952,6 @@ NTSTATUS _netr_ServerAuthenticate3(struct pipes_struct *p,
                            NETLOGON_NEG_NEUTRALIZE_NT4_EMULATION;
        }
 
-       /*
-        * If weak crypto is disabled, do not announce that we support RC4.
-        */
-       if (lp_weak_crypto() == SAMBA_WEAK_CRYPTO_DISALLOWED) {
-               srv_flgs &= ~NETLOGON_NEG_ARCFOUR;
-       }
-
        neg_flags = in_neg_flags & srv_flgs;
 
        switch (dce_call->pkt.u.request.opnum) {