Merge "Add NDK API for getprocnetwork" am: 37bc6b577c

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1722615

Change-Id: Id34d884a2c68f2c9df16f6cfc235cac9cb02ba6c
diff --git a/core/jni/Android.bp b/core/jni/Android.bp
index 382acc0..b236385 100644
--- a/core/jni/Android.bp
+++ b/core/jni/Android.bp
@@ -227,6 +227,7 @@
             shared_libs: [
                 "android.hardware.memtrack-V1-ndk_platform",
                 "libandroidicu",
+                "libandroid_net",
                 "libbpf_android",
                 "libnetdbpf",
                 "libnetdutils",
diff --git a/native/android/libandroid.map.txt b/native/android/libandroid.map.txt
index d56aa86..919fd81 100644
--- a/native/android/libandroid.map.txt
+++ b/native/android/libandroid.map.txt
@@ -274,6 +274,7 @@
     ATrace_endAsyncSection; # introduced=29
     ATrace_setCounter; # introduced=29
     android_getaddrinfofornetwork; # introduced=23
+    android_getprocnetwork; # introduced=31
     android_setprocnetwork; # introduced=23
     android_setsocknetwork; # introduced=23
     android_res_cancel; # introduced=29
diff --git a/native/android/libandroid_net.map.txt b/native/android/libandroid_net.map.txt
index 8d4e900..cc8dd72 100644
--- a/native/android/libandroid_net.map.txt
+++ b/native/android/libandroid_net.map.txt
@@ -14,6 +14,8 @@
     android_res_nquery; # llndk
     android_res_nresult; # llndk
     android_res_nsend; # llndk
+    # These functions have been part of the NDK since API 31.
+    android_getprocnetwork; # llndk
   local:
     *;
 };
diff --git a/native/android/net.c b/native/android/net.c
index a8104fc..d4b8888 100644
--- a/native/android/net.c
+++ b/native/android/net.c
@@ -22,12 +22,13 @@
 #include <stdlib.h>
 #include <sys/limits.h>
 
+// This value MUST be kept in sync with the corresponding value in
+// the android.net.Network#getNetworkHandle() implementation.
+static const uint32_t kHandleMagic = 0xcafed00d;
+static const uint32_t kHandleMagicSize = 32;
 
 static int getnetidfromhandle(net_handle_t handle, unsigned *netid) {
     static const uint32_t k32BitMask = 0xffffffff;
-    // This value MUST be kept in sync with the corresponding value in
-    // the android.net.Network#getNetworkHandle() implementation.
-    static const uint32_t kHandleMagic = 0xcafed00d;
 
     // Check for minimum acceptable version of the API in the low bits.
     if (handle != NETWORK_UNSPECIFIED &&
@@ -41,6 +42,12 @@
     return 1;
 }
 
+static net_handle_t gethandlefromnetid(unsigned netid) {
+    if (netid == NETID_UNSET) {
+        return NETWORK_UNSPECIFIED;
+    }
+    return (((net_handle_t) netid) << kHandleMagicSize) | kHandleMagic;
+}
 
 int android_setsocknetwork(net_handle_t network, int fd) {
     unsigned netid;
@@ -72,6 +79,17 @@
     return rval;
 }
 
+int android_getprocnetwork(net_handle_t *network) {
+    if (network == NULL) {
+        errno = EINVAL;
+        return -1;
+    }
+
+    unsigned netid = getNetworkForProcess();
+    *network = gethandlefromnetid(netid);
+    return 0;
+}
+
 int android_getaddrinfofornetwork(net_handle_t network,
         const char *node, const char *service,
         const struct addrinfo *hints, struct addrinfo **res) {