Add GetHostByAddrHandler to DnsProxyListener

Added functionality to handle gethostbyaddr
in DnsProxyListener. The functionality is
used by getnameinfo. The patch is part of the
work to have one dns cache for all process in
the system.

Change-Id: Ia7609160d2bd1d3bbe2b79956bd208d137a8a9ee

diff --git a/DnsProxyListener.cpp b/DnsProxyListener.cpp
index 36b78c8..b669e84 100644 (file)
--- a/DnsProxyListener.cpp
+++ b/DnsProxyListener.cpp
@@ -35,6 +35,7 @@
 DnsProxyListener::DnsProxyListener() :
                  FrameworkListener("dnsproxyd") {
     registerCmd(new GetAddrInfoCmd());
+    registerCmd(new GetHostByAddrCmd());
 }
 
 DnsProxyListener::GetAddrInfoHandler::~GetAddrInfoHandler() {
@@ -144,3 +145,79 @@ int DnsProxyListener::GetAddrInfoCmd::runCommand(SocketClient *cli,
 
     return 0;
 }
+
+/*******************************************************
+ *                  GetHostByAddr                       *
+ *******************************************************/
+DnsProxyListener::GetHostByAddrCmd::GetHostByAddrCmd() :
+        NetdCommand("gethostbyaddr") {
+}
+
+int DnsProxyListener::GetHostByAddrCmd::runCommand(SocketClient *cli,
+                                            int argc, char **argv) {
+    if (argc != 4) {
+        LOGW("Invalid number of arguments to gethostbyaddr");
+        return 0;
+    }
+
+    char* addr = argv[1];
+    addr = strdup(addr);
+
+    int addrLen = atoi(argv[2]);
+    int addrFamily = atoi(argv[3]);
+
+    DnsProxyListener::GetHostByAddrHandler* handler =
+            new DnsProxyListener::GetHostByAddrHandler(cli, addr, addrLen, addrFamily);
+    handler->start();
+
+    return 0;
+}
+
+DnsProxyListener::GetHostByAddrHandler::~GetHostByAddrHandler() {
+    free(mAddress);
+}
+
+void DnsProxyListener::GetHostByAddrHandler::start() {
+    pthread_create(&mThread, NULL,
+                   DnsProxyListener::GetHostByAddrHandler::threadStart, this);
+}
+
+void* DnsProxyListener::GetHostByAddrHandler::threadStart(void* obj) {
+    GetHostByAddrHandler* handler = reinterpret_cast<GetHostByAddrHandler*>(obj);
+    handler->run();
+    delete handler;
+    pthread_exit(NULL);
+    return NULL;
+}
+
+void DnsProxyListener::GetHostByAddrHandler::run() {
+    if (DBG) {
+        LOGD("DnsProxyListener::GetHostByAddrHandler::run\n");
+        if (mAddress) {
+            LOGD("mAdress %u.%u.%u.%u mAdressLen %d, mAddressFamily %d",
+                    mAddress[0], mAddress[1], mAddress[2], mAddress[3],
+                    mAddressLen, mAddressFamily);
+        }
+        else {
+            LOGD("mAddress = NULL");
+        }
+    }
+
+    struct hostent* hp;
+
+    hp = gethostbyaddr(mAddress, mAddressLen, mAddressFamily);
+
+    if (DBG) {
+        LOGD("GetHostByAddrHandler::run gethostbyaddr errno: %s hp->h_name = %s, name_len = %d\n",
+                hp ? "success" : strerror(errno),
+                (hp && hp->h_name) ? hp->h_name: "null",
+                (hp && hp->h_name) ? strlen(hp->h_name)+ 1 : 0);
+    }
+
+    bool success = sendLenAndData(mClient, (hp && hp->h_name) ? strlen(hp->h_name)+ 1 : 0,
+            (hp && hp->h_name) ? hp->h_name : "");
+
+    if (!success) {
+        LOGW("GetHostByAddrHandler: Error writing DNS result to client\n");
+    }
+}

diff --git a/DnsProxyListener.h b/DnsProxyListener.h
index 2d796d9..84ea6c7 100644 (file)
--- a/DnsProxyListener.h
+++ b/DnsProxyListener.h
@@ -59,6 +59,38 @@ private:
         char* mService; // owned
         struct addrinfo* mHints;  // owned
     };
+
+    /* ------ gethostbyaddr ------*/
+    class GetHostByAddrCmd : public NetdCommand {
+    public:
+        GetHostByAddrCmd();
+        virtual ~GetHostByAddrCmd() {}
+        int runCommand(SocketClient *c, int argc, char** argv);
+    };
+
+    class GetHostByAddrHandler {
+    public:
+        GetHostByAddrHandler(SocketClient *c,
+                            char* address,
+                            int   addressLen,
+                            int   addressFamily)
+            : mClient(c),
+              mAddress(address),
+              mAddressLen(addressLen),
+              mAddressFamily(addressFamily) {}
+        ~GetHostByAddrHandler();
+
+        static void* threadStart(void* handler);
+        void start();
+
+    private:
+        void run();
+        pthread_t mThread;
+        SocketClient* mClient;  // not owned
+        char* mAddress;    // address to lookup
+        int   mAddressLen; // length of address to look up
+        int   mAddressFamily;  // address family
+    };
 };
 
 #endif