diff --git a/client/NetdClient.cpp b/client/NetdClient.cpp
index 3157d3a..392b0af 100644
--- a/client/NetdClient.cpp
+++ b/client/NetdClient.cpp
@@ -65,7 +65,7 @@
     }
     if (FwmarkClient::shouldSetFwmark(family)) {
         FwmarkCommand command = {FwmarkCommand::ON_ACCEPT, 0, 0};
-        if (int error = FwmarkClient().send(&command, sizeof(command), acceptedSocket)) {
+        if (int error = FwmarkClient().send(&command, acceptedSocket)) {
             return closeFdAndSetErrno(acceptedSocket, error);
         }
     }
@@ -75,7 +75,7 @@
 int netdClientConnect(int sockfd, const sockaddr* addr, socklen_t addrlen) {
     if (sockfd >= 0 && addr && FwmarkClient::shouldSetFwmark(addr->sa_family)) {
         FwmarkCommand command = {FwmarkCommand::ON_CONNECT, 0, 0};
-        if (int error = FwmarkClient().send(&command, sizeof(command), sockfd)) {
+        if (int error = FwmarkClient().send(&command, sockfd)) {
             errno = -error;
             return -1;
         }
@@ -185,7 +185,7 @@
         return -EBADF;
     }
     FwmarkCommand command = {FwmarkCommand::SELECT_NETWORK, netId, 0};
-    return FwmarkClient().send(&command, sizeof(command), socketFd);
+    return FwmarkClient().send(&command, socketFd);
 }
 
 extern "C" int setNetworkForProcess(unsigned netId) {
@@ -201,7 +201,7 @@
         return -EBADF;
     }
     FwmarkCommand command = {FwmarkCommand::PROTECT_FROM_VPN, 0, 0};
-    return FwmarkClient().send(&command, sizeof(command), socketFd);
+    return FwmarkClient().send(&command, socketFd);
 }
 
 extern "C" int setNetworkForUser(uid_t uid, int socketFd) {
@@ -209,5 +209,10 @@
         return -EBADF;
     }
     FwmarkCommand command = {FwmarkCommand::SELECT_FOR_USER, 0, uid};
-    return FwmarkClient().send(&command, sizeof(command), socketFd);
+    return FwmarkClient().send(&command, socketFd);
+}
+
+extern "C" int queryUserAccess(uid_t uid, unsigned netId) {
+    FwmarkCommand command = {FwmarkCommand::QUERY_USER_ACCESS, netId, uid};
+    return FwmarkClient().send(&command, -1);
 }