Revert "Revert "Add NETLINK_ROUTE socket creation and event propagation""

This reverts commit 19fb0c4e5ec6a10473666a2d45267fbc8305ba85.

Conflicts:

	NetlinkManager.cpp

Brings back Stan Chesnutt's change related to adding NETLINK_ROUTE
socket creation and event propagation.

Change-Id: I8c0625a95b7996ef75b883ce764c3244dd553a47
Signed-off-by: Mike J. Chen <mjchen@google.com>
diff --git a/NetlinkManager.cpp b/NetlinkManager.cpp
index e7f0c7b..3e7a0a1 100644
--- a/NetlinkManager.cpp
+++ b/NetlinkManager.cpp
@@ -24,6 +24,7 @@
 #include <sys/un.h>
 
 #include <linux/netlink.h>
+#include <linux/rtnetlink.h>
 
 #define LOG_TAG "Netd"
 
@@ -47,7 +48,9 @@
 NetlinkManager::~NetlinkManager() {
 }
 
-int NetlinkManager::start() {
+NetlinkHandler *NetlinkManager::setupSocket(int *sock, int socketType,
+    int groups, int format) {
+
     struct sockaddr_nl nladdr;
     int sz = 64 * 1024;
     int on = 1;
@@ -55,47 +58,78 @@
     memset(&nladdr, 0, sizeof(nladdr));
     nladdr.nl_family = AF_NETLINK;
     nladdr.nl_pid = getpid();
-    nladdr.nl_groups = 0xffffffff;
+    nladdr.nl_groups = groups;
 
-    if ((mSock = socket(PF_NETLINK,
-                        SOCK_DGRAM,NETLINK_KOBJECT_UEVENT)) < 0) {
-        LOGE("Unable to create uevent socket: %s", strerror(errno));
-        return -1;
+    if ((*sock = socket(PF_NETLINK, SOCK_DGRAM, socketType)) < 0) {
+        LOGE("Unable to create netlink socket: %s", strerror(errno));
+        return NULL;
     }
 
-    if (setsockopt(mSock, SOL_SOCKET, SO_RCVBUFFORCE, &sz, sizeof(sz)) < 0) {
+    if (setsockopt(*sock, SOL_SOCKET, SO_RCVBUFFORCE, &sz, sizeof(sz)) < 0) {
         LOGE("Unable to set uevent socket SO_RCVBUFFORCE option: %s", strerror(errno));
-        return -1;
+        close(*sock);
+        return NULL;
     }
 
-    if (setsockopt(mSock, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on)) < 0) {
+    if (setsockopt(*sock, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on)) < 0) {
         SLOGE("Unable to set uevent socket SO_PASSCRED option: %s", strerror(errno));
-        return -1;
+        close(*sock);
+        return NULL;
     }
 
-    if (bind(mSock, (struct sockaddr *) &nladdr, sizeof(nladdr)) < 0) {
-        LOGE("Unable to bind uevent socket: %s", strerror(errno));
-        return -1;
+    if (bind(*sock, (struct sockaddr *) &nladdr, sizeof(nladdr)) < 0) {
+        LOGE("Unable to bind netlink socket: %s", strerror(errno));
+        close(*sock);
+        return NULL;
     }
 
-    mHandler = new NetlinkHandler(this, mSock);
-    if (mHandler->start()) {
+    NetlinkHandler *handler = new NetlinkHandler(this, *sock, format);
+    if (handler->start()) {
         LOGE("Unable to start NetlinkHandler: %s", strerror(errno));
+        close(*sock);
+        return NULL;
+    }
+
+    return handler;
+}
+
+int NetlinkManager::start() {
+    if ((mUeventHandler = setupSocket(&mUeventSock, NETLINK_KOBJECT_UEVENT,
+         0xffffffff, NetlinkListener::NETLINK_FORMAT_ASCII)) == NULL) {
+        return -1;
+    }
+
+    if ((mRouteHandler = setupSocket(&mRouteSock, NETLINK_ROUTE, RTMGRP_LINK,
+         NetlinkListener::NETLINK_FORMAT_BINARY)) == NULL) {
         return -1;
     }
     return 0;
 }
 
 int NetlinkManager::stop() {
-    if (mHandler->stop()) {
-        LOGE("Unable to stop NetlinkHandler: %s", strerror(errno));
-        return -1;
+    int status = 0;
+
+    if (mUeventHandler->stop()) {
+        LOGE("Unable to stop uevent NetlinkHandler: %s", strerror(errno));
+        status = -1;
     }
-    delete mHandler;
-    mHandler = NULL;
 
-    close(mSock);
-    mSock = -1;
+    delete mUeventHandler;
+    mUeventHandler = NULL;
 
-    return 0;
+    close(mUeventSock);
+    mUeventSock = -1;
+
+    if (mRouteHandler->stop()) {
+        LOGE("Unable to stop route NetlinkHandler: %s", strerror(errno));
+        status = -1;
+    }
+
+    delete mRouteHandler;
+    mRouteHandler = NULL;
+
+    close(mRouteSock);
+    mRouteSock = -1;
+
+    return status;
 }