ksmbd: set NTLMSSP_NEGOTIATE_SEAL flag to challenge blob

If NTLMSSP_NEGOTIATE_SEAL flags is set in negotiate blob from client,
Set NTLMSSP_NEGOTIATE_SEAL flag to challenge blob.
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

fs/ksmbd/auth.c

@@ -424,6 +424,9 @@ ksmbd_build_ntlmssp_challenge_blob(struct challenge_message *chgblob,
 				   NTLMSSP_NEGOTIATE_56);
 	}
 
+	if (cflags & NTLMSSP_NEGOTIATE_SEAL && smb3_encryption_negotiated(conn))
+		flags |= NTLMSSP_NEGOTIATE_SEAL;
+
 	if (cflags & NTLMSSP_NEGOTIATE_ALWAYS_SIGN)
 		flags |= NTLMSSP_NEGOTIATE_ALWAYS_SIGN;
 

fs/ksmbd/smb2pdu.c

@@ -925,7 +925,7 @@ static void decode_encrypt_ctxt(struct ksmbd_conn *conn,
  *
  * Return:	true if connection should be encrypted, else false
  */
-static bool smb3_encryption_negotiated(struct ksmbd_conn *conn)
+bool smb3_encryption_negotiated(struct ksmbd_conn *conn)
 {
 	if (!conn->ops->generate_encryptionkey)
 		return false;

fs/ksmbd/smb2pdu.h

@@ -494,6 +494,7 @@ int smb3_decrypt_req(struct ksmbd_work *work);
 int smb3_encrypt_resp(struct ksmbd_work *work);
 bool smb3_11_final_sess_setup_resp(struct ksmbd_work *work);
 int smb2_set_rsp_credits(struct ksmbd_work *work);
+bool smb3_encryption_negotiated(struct ksmbd_conn *conn);
 
 /* smb2 misc functions */
 int ksmbd_smb2_check_message(struct ksmbd_work *work);