Fix testApfFilterKeepaliveAck.

Apf program for TCP keep alive ACK also compares protocol field in IPv4
header and the total length of TCP keep alive ACK packet. Besides,
should set the ACK flag in the the TCP header of keep alive ACK packet.

Bug: 123992564
Test: atest NetworkStackTests
Change-Id: I997cd6807a33f7e1af25566226d803dcc2e257dd

1 files changed, 23 insertions, 19 deletions

diff --git a/tests/src/android/net/apf/ApfTest.java b/tests/src/android/net/apf/ApfTest.java
index a4a1000..af71ac5 100644
--- a/tests/src/android/net/apf/ApfTest.java
+++ b/tests/src/android/net/apf/ApfTest.java
@@ -22,6 +22,7 @@ import static android.system.OsConstants.ETH_P_ARP;
 import static android.system.OsConstants.ETH_P_IP;
 import static android.system.OsConstants.ETH_P_IPV6;
 import static android.system.OsConstants.IPPROTO_ICMPV6;
+import static android.system.OsConstants.IPPROTO_TCP;
 import static android.system.OsConstants.IPPROTO_UDP;
 import static android.system.OsConstants.SOCK_STREAM;
 
@@ -1017,6 +1018,7 @@ public class ApfTest {
     private static final int IPV4_TCP_SEQ_NUM_OFFSET = IPV4_TCP_HEADER_OFFSET + 4;
     private static final int IPV4_TCP_ACK_NUM_OFFSET = IPV4_TCP_HEADER_OFFSET + 8;
     private static final int IPV4_TCP_HEADER_LENGTH_OFFSET = IPV4_TCP_HEADER_OFFSET + 12;
+    private static final int IPV4_TCP_HEADER_FLAG_OFFSET = IPV4_TCP_HEADER_OFFSET + 13;
     private static final byte[] IPV4_BROADCAST_ADDRESS =
             {(byte) 255, (byte) 255, (byte) 255, (byte) 255};
 
@@ -1568,7 +1570,7 @@ public class ApfTest {
         // Verify IPv4 packet from another address is passed
         assertPass(program,
                 ipv4Packet(IPV4_ANOTHER_ADDR, IPV4_KEEPALIVE_SRC_ADDR, anotherSrcPort,
-                        anotherDstPort, anotherSeqNum, anotherAckNum));
+                        anotherDstPort, anotherSeqNum, anotherAckNum, 0 /* dataLength */));
 
         // Remove IPv4 keepalive filter
         apfFilter.removeKeepalivePacketFilter(slot1);
@@ -1613,15 +1615,15 @@ public class ApfTest {
             // dst: 10.0.0.5, port: 12345
             assertDrop(program,
                     ipv4Packet(IPV4_KEEPALIVE_DST_ADDR, IPV4_KEEPALIVE_SRC_ADDR,
-                            dstPort, srcPort, ackNum, seqNum + 1));
+                            dstPort, srcPort, ackNum, seqNum + 1, 0 /* dataLength */));
             // Verify IPv4 non-keepalive ack packet from the same source address is passed
             assertPass(program,
                     ipv4Packet(IPV4_KEEPALIVE_DST_ADDR, IPV4_KEEPALIVE_SRC_ADDR,
-                            dstPort, srcPort, ackNum + 100, seqNum));
+                            dstPort, srcPort, ackNum + 100, seqNum, 0 /* dataLength */));
             // Verify IPv4 packet from another address is passed
             assertPass(program,
                     ipv4Packet(IPV4_ANOTHER_ADDR, IPV4_KEEPALIVE_SRC_ADDR, anotherSrcPort,
-                            anotherDstPort, anotherSeqNum, anotherAckNum));
+                            anotherDstPort, anotherSeqNum, anotherAckNum, 0 /* dataLength */));
 
             // Verify IPv6 keepalive ack packet is dropped
             // src: 2404:0:0:0:0:0:faf2, port: 54321
@@ -1650,13 +1652,13 @@ public class ApfTest {
         // Verify IPv4, IPv6 packets are passed
         assertPass(program,
                 ipv4Packet(IPV4_KEEPALIVE_DST_ADDR, IPV4_KEEPALIVE_SRC_ADDR,
-                        dstPort, srcPort, ackNum, seqNum + 1));
+                        dstPort, srcPort, ackNum, seqNum + 1, 0 /* dataLength */));
         assertPass(program,
                 ipv6Packet(IPV6_KEEPALIVE_DST_ADDR, IPV6_KEEPALIVE_SRC_ADDR,
                         dstPort, srcPort, ackNum, seqNum + 1));
         assertPass(program,
                 ipv4Packet(IPV4_ANOTHER_ADDR, IPV4_KEEPALIVE_SRC_ADDR, srcPort,
-                        dstPort, anotherSeqNum, anotherAckNum));
+                        dstPort, anotherSeqNum, anotherAckNum, 0 /* dataLength */));
         assertPass(program,
                 ipv6Packet(IPV6_ANOTHER_ADDR, IPV6_KEEPALIVE_SRC_ADDR, srcPort,
                         dstPort, anotherSeqNum, anotherAckNum));
@@ -1664,28 +1666,30 @@ public class ApfTest {
         apfFilter.shutdown();
     }
 
-    private static byte[] ipv4Packet(byte[] sip, byte[] tip, int sport,
-            int dport, int seq, int ack) {
-        ByteBuffer packet = ByteBuffer.wrap(new byte[100]);
+    private static byte[] ipv4Packet(byte[] sip, byte[] dip, int sport,
+            int dport, int seq, int ack, int dataLength) {
+        final int totalLength = dataLength + IPV4_HEADER_LEN + IPV4_TCP_HEADER_LEN;
+
+        ByteBuffer packet = ByteBuffer.wrap(new byte[totalLength + ETH_HEADER_LEN]);
+
+        // ether type
         packet.putShort(ETH_ETHERTYPE_OFFSET, (short) ETH_P_IP);
+
+        // IPv4 header
         packet.put(IPV4_VERSION_IHL_OFFSET, (byte) 0x45);
+        packet.putShort(IPV4_TOTAL_LENGTH_OFFSET, (short) totalLength);
+        packet.put(IPV4_PROTOCOL_OFFSET, (byte) IPPROTO_TCP);
         put(packet, IPV4_SRC_ADDR_OFFSET, sip);
-        put(packet, IPV4_DEST_ADDR_OFFSET, tip);
+        put(packet, IPV4_DEST_ADDR_OFFSET, dip);
         packet.putShort(IPV4_TCP_SRC_PORT_OFFSET, (short) sport);
         packet.putShort(IPV4_TCP_DEST_PORT_OFFSET, (short) dport);
         packet.putInt(IPV4_TCP_SEQ_NUM_OFFSET, seq);
         packet.putInt(IPV4_TCP_ACK_NUM_OFFSET, ack);
-        return packet.array();
-    }
 
-    private static byte[] ipv4Packet(byte[] sip, byte[] tip, int sport,
-            int dport, int seq, int ack, int dataLength) {
-        final int totalLength = dataLength + IPV4_HEADER_LEN + IPV4_TCP_HEADER_LEN;
-
-        ByteBuffer packet = ByteBuffer.wrap(ipv4Packet(sip, tip, sport, dport, seq, ack));
-        packet.putShort(IPV4_TOTAL_LENGTH_OFFSET, (short) totalLength);
-        // TCP header length 5, reserved 3 bits, NS=0
+        // TCP header length 5(20 bytes), reserved 3 bits, NS=0
         packet.put(IPV4_TCP_HEADER_LENGTH_OFFSET, (byte) 0x50);
+        // TCP flags: ACK set
+        packet.put(IPV4_TCP_HEADER_FLAG_OFFSET, (byte) 0x10);
         return packet.array();
     }