Add POSIX support for transport remove

c/meterpreter/source/common/arch/posix/base_dispatch.c

@@ -250,6 +250,48 @@ BOOL remote_request_core_transport_prev(Remote* remote, Packet* packet, DWORD* r
 	return *result == ERROR_SUCCESS ? FALSE : TRUE;
 }
 
+DWORD remote_request_core_transport_remove(Remote* remote, Packet* packet)
+{
+	DWORD result = ERROR_SUCCESS;
+
+	// make sure we are not trying to remove the last transport
+	if (remote->transport == remote->transport->prev_transport) {
+		dprintf("[DISPATCH] Refusing to delete the last transport");
+		result = ERROR_INVALID_FUNCTION;
+	}
+	else {
+		Transport* found = NULL;
+		Transport* transport = remote->transport;
+		char* transportUrl = packet_get_tlv_value_string(packet, TLV_TYPE_TRANS_URL);
+
+		do {
+			if (strcmp(transportUrl, transport->url) == 0) {
+				found = transport;
+				break;
+			}
+
+			transport = transport->next_transport;
+		} while (transport != remote->transport);
+
+		if (found == NULL || found == remote->transport) {
+			dprintf("[DISPATCH] Transport not found, or attempting to remove current");
+			// if we don't have a valid transport, or they're trying to remove the
+			// existing one, then bomb out (that might come later)
+			result = ERROR_INVALID_PARAMETER;
+		}
+		else {
+			remote->trans_remove(remote, found);
+			dprintf("[DISPATCH] Transport removed");
+		}
+
+		SAFE_FREE(transportUrl);
+	}
+
+	packet_transmit_empty_response(remote, packet, result);
+	dprintf("[DISPATCH] Response sent.");
+	return result;
+}
+
 DWORD remote_request_core_transport_add(Remote* remote, Packet* packet)
 {
 	Transport* transport = NULL;

c/meterpreter/source/common/compat_types.h

@@ -207,6 +207,7 @@ typedef uint64_t	QWORD;
 #define ERROR_INVALID_PARAMETER	EINVAL
 #define ERROR_INVALID_HANDLE   	EINVAL
 #define ERROR_INVALID_DATA     	EINVAL
+#define ERROR_INVALID_FUNCTION 	EINVAL
 #define ERROR_UNSUPPORTED_COMPRESSION	EINVAL
 #define	ERROR_NOT_SUPPORTED	EOPNOTSUPP
 

c/meterpreter/source/server/server_setup_posix.c

@@ -1115,7 +1115,7 @@ static void append_transport(Transport** list, Transport* newTransport) {
 
 static void remove_transport(Remote* remote, Transport* oldTransport) {
 	// if we point to ourself, then we're the last one
-	if (remote->transport->next_transport == oldTransport) {
+	if (remote->transport->next_transport == remote->transport) {
 		remote->transport = NULL;
 	}
 	else {
@@ -1294,6 +1294,8 @@ DWORD server_setup(MetsrvConfig* config)
 
 	// Set up the transport creation function pointer
 	remote->trans_create = create_transport;
+	// Set up the transport removal function pointer
+	remote->trans_remove = remove_transport;
 	// and the config creation pointer
 	remote->config_create = config_create;