s3-dcerpc: avoid talloc_move on schannel creds in cli_rpc_pipe_open_schannel_with_key().

Initially, the schannel creds were talloc memduped, then, during the netlogon
creds client merge (baf7274fed) they were first
talloc_referenced and then later (53765c81f7)
talloc_moved.

The issue with using talloc_move here is that users of that function in winbind
will only be able to have two schanneled connections, as the cached schannel
credentials pointer from the netlogon pipe will be set to NULL. Do a deep copy
of the struct instead.

Guenther

libcli/auth/credentials.c

@@ -24,6 +24,7 @@
 #include "system/time.h"
 #include "../lib/crypto/crypto.h"
 #include "libcli/auth/libcli_auth.h"
+#include "../libcli/security/dom_sid.h"
 
 static void netlogon_creds_step_crypt(struct netlogon_creds_CredentialState *creds,
 				      const struct netr_Credential *in,
@@ -202,7 +203,7 @@ struct netlogon_creds_CredentialState *netlogon_creds_client_init(TALLOC_CTX *me
 								  struct netr_Credential *initial_credential,
 								  uint32_t negotiate_flags)
 {
-	struct netlogon_creds_CredentialState *creds = talloc(mem_ctx, struct netlogon_creds_CredentialState);
+	struct netlogon_creds_CredentialState *creds = talloc_zero(mem_ctx, struct netlogon_creds_CredentialState);
 	
 	if (!creds) {
 		return NULL;
@@ -454,3 +455,46 @@ void netlogon_creds_decrypt_samlogon(struct netlogon_creds_CredentialState *cred
 	}
 }	
 
+/*
+  copy a netlogon_creds_CredentialState struct
+*/
+
+struct netlogon_creds_CredentialState *netlogon_creds_copy(TALLOC_CTX *mem_ctx,
+							   struct netlogon_creds_CredentialState *creds_in)
+{
+	struct netlogon_creds_CredentialState *creds = talloc_zero(mem_ctx, struct netlogon_creds_CredentialState);
+
+	if (!creds) {
+		return NULL;
+	}
+
+	creds->sequence			= creds_in->sequence;
+	creds->negotiate_flags		= creds_in->negotiate_flags;
+	creds->secure_channel_type	= creds_in->secure_channel_type;
+
+	creds->computer_name = talloc_strdup(creds, creds_in->computer_name);
+	if (!creds->computer_name) {
+		talloc_free(creds);
+		return NULL;
+	}
+	creds->account_name = talloc_strdup(creds, creds_in->account_name);
+	if (!creds->account_name) {
+		talloc_free(creds);
+		return NULL;
+	}
+
+	if (creds_in->sid) {
+		creds->sid = dom_sid_dup(creds, creds_in->sid);
+		if (!creds->sid) {
+			talloc_free(creds);
+			return NULL;
+		}
+	}
+
+	memcpy(creds->session_key, creds_in->session_key, sizeof(creds->session_key));
+	memcpy(creds->seed.data, creds_in->seed.data, sizeof(creds->seed.data));
+	memcpy(creds->client.data, creds_in->client.data, sizeof(creds->client.data));
+	memcpy(creds->server.data, creds_in->server.data, sizeof(creds->server.data));
+
+	return creds;
+}

libcli/auth/proto.h

@@ -35,6 +35,8 @@ void netlogon_creds_client_authenticator(struct netlogon_creds_CredentialState *
 				struct netr_Authenticator *next);
 bool netlogon_creds_client_check(struct netlogon_creds_CredentialState *creds,
 			const struct netr_Credential *received_credentials);
+struct netlogon_creds_CredentialState *netlogon_creds_copy(TALLOC_CTX *mem_ctx,
+							   struct netlogon_creds_CredentialState *creds_in);
 
 /*****************************************************************
 The above functions are common to the client and server interface

source3/rpc_client/cli_pipe.c

@@ -2383,7 +2383,7 @@ NTSTATUS rpccli_schannel_bind_data(TALLOC_CTX *mem_ctx, const char *domain,
 	result->a_u.schannel_auth->state = SCHANNEL_STATE_START;
 	result->a_u.schannel_auth->seq_num = 0;
 	result->a_u.schannel_auth->initiator = true;
-	result->a_u.schannel_auth->creds = creds;
+	result->a_u.schannel_auth->creds = netlogon_creds_copy(result, creds);
 
 	*presult = result;
 	return NT_STATUS_OK;
@@ -3048,9 +3048,13 @@ NTSTATUS cli_rpc_pipe_open_schannel_with_key(struct cli_state *cli,
 
 	/*
 	 * The credentials on a new netlogon pipe are the ones we are passed
-	 * in - reference them in
+	 * in - copy them over
 	 */
-	result->dc = talloc_move(result, pdc);
+	result->dc = netlogon_creds_copy(result, *pdc);
+	if (result->dc == NULL) {
+		TALLOC_FREE(result);
+		return NT_STATUS_NO_MEMORY;
+	}
 
 	DEBUG(10,("cli_rpc_pipe_open_schannel_with_key: opened pipe %s to machine %s "
 		  "for domain %s and bound using schannel.\n",