Merge "DeviceInfoUtils: add class and helper for three-part version number"
diff --git a/staticlibs/device/com/android/net/module/util/PacketBuilder.java b/staticlibs/device/com/android/net/module/util/PacketBuilder.java
index 8acb296..33e5bfa 100644
--- a/staticlibs/device/com/android/net/module/util/PacketBuilder.java
+++ b/staticlibs/device/com/android/net/module/util/PacketBuilder.java
@@ -26,6 +26,7 @@
 import static com.android.net.module.util.IpUtils.udpChecksum;
 import static com.android.net.module.util.NetworkStackConstants.IPV4_CHECKSUM_OFFSET;
 import static com.android.net.module.util.NetworkStackConstants.IPV4_LENGTH_OFFSET;
+import static com.android.net.module.util.NetworkStackConstants.IPV6_HEADER_LEN;
 import static com.android.net.module.util.NetworkStackConstants.IPV6_LEN_OFFSET;
 import static com.android.net.module.util.NetworkStackConstants.TCP_CHECKSUM_OFFSET;
 import static com.android.net.module.util.NetworkStackConstants.UDP_CHECKSUM_OFFSET;
@@ -100,9 +101,9 @@
      */
     public void writeL2Header(MacAddress srcMac, MacAddress dstMac, short etherType) throws
             IOException {
-        final EthernetHeader ethv4Header = new EthernetHeader(dstMac, srcMac, etherType);
+        final EthernetHeader ethHeader = new EthernetHeader(dstMac, srcMac, etherType);
         try {
-            ethv4Header.writeToByteBuffer(mBuffer);
+            ethHeader.writeToByteBuffer(mBuffer);
         } catch (IllegalArgumentException | BufferOverflowException e) {
             throw new IOException("Error writing to buffer: ", e);
         }
@@ -218,7 +219,7 @@
      */
     @NonNull
     public ByteBuffer finalizePacket() throws IOException {
-        // Finalize IPv4 or IPv6 header.
+        // [1] Finalize IPv4 or IPv6 header.
         int ipHeaderOffset = INVALID_OFFSET;
         if (mIpv4HeaderOffset != INVALID_OFFSET) {
             ipHeaderOffset = mIpv4HeaderOffset;
@@ -234,13 +235,14 @@
             ipHeaderOffset = mIpv6HeaderOffset;
 
             // Populate the IPv6 payloadLength field.
+            // The payload length doesn't include IPv6 header length. See rfc8200 section 3.
             mBuffer.putShort(mIpv6HeaderOffset + IPV6_LEN_OFFSET,
-                    (short) (mBuffer.position() - mIpv6HeaderOffset));
+                    (short) (mBuffer.position() - mIpv6HeaderOffset - IPV6_HEADER_LEN));
         } else {
             throw new IOException("Packet is missing neither IPv4 nor IPv6 header");
         }
 
-        // Finalize TCP or UDP header.
+        // [2] Finalize TCP or UDP header.
         if (mTcpHeaderOffset != INVALID_OFFSET) {
             // Populate the TCP header checksum field.
             mBuffer.putShort(mTcpHeaderOffset + TCP_CHECKSUM_OFFSET, tcpChecksum(mBuffer,
diff --git a/staticlibs/native/bpf_headers/include/bpf/BpfUtils.h b/staticlibs/native/bpf_headers/include/bpf/BpfUtils.h
index 7801c3e..3f06896 100644
--- a/staticlibs/native/bpf_headers/include/bpf/BpfUtils.h
+++ b/staticlibs/native/bpf_headers/include/bpf/BpfUtils.h
@@ -60,6 +60,9 @@
     // This is a temporary hack for network stats map swap on devices running
     // 4.9 kernels. The kernel code of socket release on pf_key socket will
     // explicitly call synchronize_rcu() which is exactly what we need.
+    //
+    // Linux 4.14/4.19/5.4/5.10/5.15 (and 5.18) still have this same behaviour.
+    // see net/key/af_key.c: pfkey_release() -> synchronize_rcu()
     int pfSocket = socket(AF_KEY, SOCK_RAW | SOCK_CLOEXEC, PF_KEY_V2);
 
     if (pfSocket < 0) {
diff --git a/staticlibs/tests/unit/src/com/android/net/module/util/PacketBuilderTest.java b/staticlibs/tests/unit/src/com/android/net/module/util/PacketBuilderTest.java
index 1a0752a..e40cd6b 100644
--- a/staticlibs/tests/unit/src/com/android/net/module/util/PacketBuilderTest.java
+++ b/staticlibs/tests/unit/src/com/android/net/module/util/PacketBuilderTest.java
@@ -24,7 +24,6 @@
 import static com.android.net.module.util.NetworkStackConstants.ETHER_TYPE_IPV4;
 import static com.android.net.module.util.NetworkStackConstants.ETHER_TYPE_IPV6;
 import static com.android.net.module.util.NetworkStackConstants.IPV4_HEADER_MIN_LEN;
-import static com.android.net.module.util.NetworkStackConstants.IPV6_HEADER_LEN;
 import static com.android.net.module.util.NetworkStackConstants.TCPHDR_ACK;
 import static com.android.net.module.util.NetworkStackConstants.TCP_HEADER_MIN_LEN;
 import static com.android.net.module.util.NetworkStackConstants.UDP_HEADER_LEN;
@@ -271,9 +270,8 @@
                 // packet = (scapy.Ether(src="11:22:33:44:55:66", dst="aa:bb:cc:dd:ee:ff",
                 //                     type='IPv6') /
                 //           scapy.IPv6(src="2001:db8::1", dst="2001:db8::2", tc=0x80,
-                //                      fl=0x515ca, plen=48, hlim=0x40) /
+                //                      fl=0x515ca, hlim=0x40) /
                 //           scapy.UDP(sport=9876, dport=433))
-                // Note that plen(48) = ipv6hdr(40) + udphdr(8).
                 // Ether header
                 (byte) 0xaa, (byte) 0xbb, (byte) 0xcc, (byte) 0xdd,
                 (byte) 0xee, (byte) 0xff, (byte) 0x11, (byte) 0x22,
@@ -281,7 +279,7 @@
                 (byte) 0x86, (byte) 0xdd,
                 // IP header
                 (byte) 0x68, (byte) 0x05, (byte) 0x15, (byte) 0xca,
-                (byte) 0x00, (byte) 0x30, (byte) 0x11, (byte) 0x40,
+                (byte) 0x00, (byte) 0x08, (byte) 0x11, (byte) 0x40,
                 (byte) 0x20, (byte) 0x01, (byte) 0x0d, (byte) 0xb8,
                 (byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
                 (byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
@@ -300,10 +298,9 @@
                 // packet = (scapy.Ether(src="11:22:33:44:55:66", dst="aa:bb:cc:dd:ee:ff",
                 //                       type='IPv6') /
                 //           scapy.IPv6(src="2001:db8::1", dst="2001:db8::2", tc=0x80,
-                //                      fl=0x515ca, plen=52, hlim=0x40) /
+                //                      fl=0x515ca, hlim=0x40) /
                 //           scapy.UDP(sport=9876, dport=433) /
                 //           b'\xde\xad\xbe\xef')
-                // Note that plen(52) = ipv6hdr(40) + udphdr(8) + data(4).
                 // Ether header
                 (byte) 0xaa, (byte) 0xbb, (byte) 0xcc, (byte) 0xdd,
                 (byte) 0xee, (byte) 0xff, (byte) 0x11, (byte) 0x22,
@@ -311,7 +308,7 @@
                 (byte) 0x86, (byte) 0xdd,
                 // IP header
                 (byte) 0x68, (byte) 0x05, (byte) 0x15, (byte) 0xca,
-                (byte) 0x00, (byte) 0x34, (byte) 0x11, (byte) 0x40,
+                (byte) 0x00, (byte) 0x0c, (byte) 0x11, (byte) 0x40,
                 (byte) 0x20, (byte) 0x01, (byte) 0x0d, (byte) 0xb8,
                 (byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
                 (byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
@@ -332,11 +329,10 @@
                 // packet = (scapy.Ether(src="11:22:33:44:55:66", dst="aa:bb:cc:dd:ee:ff",
                 //                       type='IPv6') /
                 //           scapy.IPv6(src="2001:db8::1", dst="2001:db8::2", tc=0x80,
-                //                      fl=0x515ca, plen=64, hlim=0x40) /
+                //                      fl=0x515ca, hlim=0x40) /
                 //           scapy.TCP(sport=9876, dport=433, seq=13579, ack=24680,
                 //                     flags='A', window=8192, urgptr=0) /
                 //           b'\xde\xad\xbe\xef')
-                // Note that plen(64) = ipv6hdr(40) + udphdr(20) + data(4).
                 // Ether header
                 (byte) 0xaa, (byte) 0xbb, (byte) 0xcc, (byte) 0xdd,
                 (byte) 0xee, (byte) 0xff, (byte) 0x11, (byte) 0x22,
@@ -344,7 +340,7 @@
                 (byte) 0x86, (byte) 0xdd,
                 // IPv6 header
                 (byte) 0x68, (byte) 0x05, (byte) 0x15, (byte) 0xca,
-                (byte) 0x00, (byte) 0x40, (byte) 0x06, (byte) 0x40,
+                (byte) 0x00, (byte) 0x18, (byte) 0x06, (byte) 0x40,
                 (byte) 0x20, (byte) 0x01, (byte) 0x0d, (byte) 0xb8,
                 (byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
                 (byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
@@ -368,10 +364,9 @@
                 // packet = (scapy.Ether(src="11:22:33:44:55:66", dst="aa:bb:cc:dd:ee:ff",
                 //                       type='IPv6') /
                 //           scapy.IPv6(src="2001:db8::1", dst="2001:db8::2", tc=0x80,
-                //                      fl=0x515ca, plen=60, hlim=0x40) /
+                //                      fl=0x515ca, hlim=0x40) /
                 //           scapy.TCP(sport=9876, dport=433, seq=13579, ack=24680,
                 //                     flags='A', window=8192, urgptr=0))
-                // Note that plen(60) = ipv6hdr(40) + udphdr(20).
                 // Ether header
                 (byte) 0xaa, (byte) 0xbb, (byte) 0xcc, (byte) 0xdd,
                 (byte) 0xee, (byte) 0xff, (byte) 0x11, (byte) 0x22,
@@ -379,7 +374,7 @@
                 (byte) 0x86, (byte) 0xdd,
                 // IPv6 header
                 (byte) 0x68, (byte) 0x05, (byte) 0x15, (byte) 0xca,
-                (byte) 0x00, (byte) 0x3c, (byte) 0x06, (byte) 0x40,
+                (byte) 0x00, (byte) 0x14, (byte) 0x06, (byte) 0x40,
                 (byte) 0x20, (byte) 0x01, (byte) 0x0d, (byte) 0xb8,
                 (byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
                 (byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
@@ -399,14 +394,13 @@
     private static final byte[] TEST_PACKET_IPV6HDR_TCPHDR_DATA =
             new byte[] {
                 // packet = (scapy.IPv6(src="2001:db8::1", dst="2001:db8::2", tc=0x80,
-                //                      fl=0x515ca, plen=64, hlim=0x40) /
+                //                      fl=0x515ca, hlim=0x40) /
                 //           scapy.TCP(sport=9876, dport=433, seq=13579, ack=24680,
                 //                     flags='A', window=8192, urgptr=0) /
                 //           b'\xde\xad\xbe\xef')
-                // Note that plen(64) = ipv6hdr(40) + udphdr(20) + data(4).
                 // IPv6 header
                 (byte) 0x68, (byte) 0x05, (byte) 0x15, (byte) 0xca,
-                (byte) 0x00, (byte) 0x40, (byte) 0x06, (byte) 0x40,
+                (byte) 0x00, (byte) 0x18, (byte) 0x06, (byte) 0x40,
                 (byte) 0x20, (byte) 0x01, (byte) 0x0d, (byte) 0xb8,
                 (byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
                 (byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
@@ -428,13 +422,12 @@
     private static final byte[] TEST_PACKET_IPV6HDR_TCPHDR =
             new byte[] {
                 // packet = (scapy.IPv6(src="2001:db8::1", dst="2001:db8::2", tc=0x80,
-                //                      fl=0x515ca, plen=60, hlim=0x40) /
+                //                      fl=0x515ca, hlim=0x40) /
                 //           scapy.TCP(sport=9876, dport=433, seq=13579, ack=24680,
                 //                     flags='A', window=8192, urgptr=0))
-                // Note that plen(60) = ipv6hdr(40) + udphdr(20).
                 // IPv6 header
                 (byte) 0x68, (byte) 0x05, (byte) 0x15, (byte) 0xca,
-                (byte) 0x00, (byte) 0x3c, (byte) 0x06, (byte) 0x40,
+                (byte) 0x00, (byte) 0x14, (byte) 0x06, (byte) 0x40,
                 (byte) 0x20, (byte) 0x01, (byte) 0x0d, (byte) 0xb8,
                 (byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
                 (byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
@@ -454,12 +447,11 @@
     private static final byte[] TEST_PACKET_IPV6HDR_UDPHDR =
             new byte[] {
                 // packet = (scapy.IPv6(src="2001:db8::1", dst="2001:db8::2", tc=0x80,
-                //                      fl=0x515ca, plen=48, hlim=0x40) /
+                //                      fl=0x515ca, hlim=0x40) /
                 //           scapy.UDP(sport=9876, dport=433))
-                // Note that plen(48) = ipv6hdr(40) + udphdr(8).
                 // IP header
                 (byte) 0x68, (byte) 0x05, (byte) 0x15, (byte) 0xca,
-                (byte) 0x00, (byte) 0x30, (byte) 0x11, (byte) 0x40,
+                (byte) 0x00, (byte) 0x08, (byte) 0x11, (byte) 0x40,
                 (byte) 0x20, (byte) 0x01, (byte) 0x0d, (byte) 0xb8,
                 (byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
                 (byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
@@ -476,13 +468,12 @@
     private static final byte[] TEST_PACKET_IPV6HDR_UDPHDR_DATA =
             new byte[] {
                 // packet = (scapy.IPv6(src="2001:db8::1", dst="2001:db8::2", tc=0x80,
-                //                      fl=0x515ca, plen=52, hlim=0x40) /
+                //                      fl=0x515ca, hlim=0x40) /
                 //           scapy.UDP(sport=9876, dport=433) /
                 //           b'\xde\xad\xbe\xef')
-                // Note that plen(52) = ipv6hdr(40) + udphdr(8) + data(4).
                 // IP header
                 (byte) 0x68, (byte) 0x05, (byte) 0x15, (byte) 0xca,
-                (byte) 0x00, (byte) 0x34, (byte) 0x11, (byte) 0x40,
+                (byte) 0x00, (byte) 0x0c, (byte) 0x11, (byte) 0x40,
                 (byte) 0x20, (byte) 0x01, (byte) 0x0d, (byte) 0xb8,
                 (byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
                 (byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
@@ -653,12 +644,10 @@
 
         final int dataLength = hasData ? DATA.limit() : 0;
         if (l4proto == IPPROTO_TCP) {
-            assertEquals(IPV6_HEADER_LEN + TCP_HEADER_MIN_LEN + dataLength,
-                    ipv6Header.payloadLength);
+            assertEquals(TCP_HEADER_MIN_LEN + dataLength, ipv6Header.payloadLength);
             assertEquals((byte) IPPROTO_TCP, ipv6Header.nextHeader);
         } else if (l4proto == IPPROTO_UDP) {
-            assertEquals(IPV6_HEADER_LEN + UDP_HEADER_LEN + dataLength,
-                    ipv6Header.payloadLength);
+            assertEquals(UDP_HEADER_LEN + dataLength, ipv6Header.payloadLength);
             assertEquals((byte) IPPROTO_UDP, ipv6Header.nextHeader);
         }
     }