More APF debuggability. (059e2bb3) · Commits · e / os / android_frameworks_base

services/net/java/android/net/apf/ApfFilter.java

+50 −18

Original line number	Diff line number	Diff line
		@@ -252,15 +252,22 @@ public class ApfFilter {
		long mLastSeen;

		// For debugging only. Offsets into the packet where PIOs are.
		private final ArrayList<Integer> mPrefixOptionOffsets;
		private final ArrayList<Integer> mPrefixOptionOffsets = new ArrayList<>();

		// For debugging only. Offsets into the packet where RDNSS options are.
		private final ArrayList<Integer> mRdnssOptionOffsets = new ArrayList<>();

		// For debugging only. How many times this RA was seen.
		int seenCount = 0;

		// For debugging only. Returns the hex representation of the last matching packet.
		String getLastMatchingPacket() {
		return HexDump.toHexString(mPacket.array(), 0, mPacket.capacity(), false /* lowercase */);
		return HexDump.toHexString(mPacket.array(), 0, mPacket.capacity(),
		false /* lowercase */);
		}

		// For debugging only. Returns the string representation of the IPv6 address starting at
		// position pos in the packet.
		private String IPv6AddresstoString(int pos) {
		try {
		byte[] array = mPacket.array();
		@@ -295,19 +302,37 @@ public class ApfFilter {
		return s & 0xffffffff;
		}

		private void prefixOptionToString(StringBuffer sb, int offset) {
		String prefix = IPv6AddresstoString(offset + 16);
		int length = uint8(mPacket.get(offset + 2));
		long valid = mPacket.getInt(offset + 4);
		long preferred = mPacket.getInt(offset + 8);
		sb.append(String.format("%s/%d %ds/%ds ", prefix, length, valid, preferred));
		}

		private void rdnssOptionToString(StringBuffer sb, int offset) {
		int optLen = uint8(mPacket.get(offset + 1)) * 8;
		if (optLen < 24) return; // Malformed or empty.
		long lifetime = uint32(mPacket.getInt(offset + 4));
		int numServers = (optLen - 8) / 16;
		sb.append("DNS ").append(lifetime).append("s");
		for (int server = 0; server < numServers; server++) {
		sb.append(" ").append(IPv6AddresstoString(offset + 8 + 16 * server));
		}
		}

		public String toString() {
		try {
		StringBuffer sb = new StringBuffer();
		sb.append(String.format("RA %s -> %s %d ",
		sb.append(String.format("RA %s -> %s %ds ",
		IPv6AddresstoString(IPV6_SRC_ADDR_OFFSET),
		IPv6AddresstoString(IPV6_DEST_ADDR_OFFSET),
		uint16(mPacket.getShort(ICMP6_RA_ROUTER_LIFETIME_OFFSET))));
		for (int i: mPrefixOptionOffsets) {
		String prefix = IPv6AddresstoString(i + 16);
		int length = uint8(mPacket.get(i + 2));
		long valid = mPacket.getInt(i + 4);
		long preferred = mPacket.getInt(i + 8);
		sb.append(String.format("%s/%d %d/%d ", prefix, length, valid, preferred));
		prefixOptionToString(sb, i);
		}
		for (int i: mRdnssOptionOffsets) {
		rdnssOptionToString(sb, i);
		}
		return sb.toString();
		} catch (BufferUnderflowException \| IndexOutOfBoundsException e) {
		@@ -352,8 +377,7 @@ public class ApfFilter {
		ICMP6_RA_ROUTER_LIFETIME_OFFSET,
		ICMP6_RA_ROUTER_LIFETIME_LEN);

		// Parse ICMPv6 options
		mPrefixOptionOffsets = new ArrayList<>();
		// Ensures that the RA is not truncated.
		mPacket.position(ICMP6_RA_OPTION_OFFSET);
		while (mPacket.hasRemaining()) {
		int optionType = ((int)mPacket.get(mPacket.position())) & 0xff;
		@@ -372,8 +396,10 @@ public class ApfFilter {
		break;
		// These three options have the same lifetime offset and size, so process
		// together:
		case ICMP6_ROUTE_INFO_OPTION_TYPE:
		case ICMP6_RDNSS_OPTION_TYPE:
		mRdnssOptionOffsets.add(mPacket.position());
		// Fall through.
		case ICMP6_ROUTE_INFO_OPTION_TYPE:
		case ICMP6_DNSSL_OPTION_TYPE:
		// Parse lifetime
		lastNonLifetimeStart = addNonLifetime(lastNonLifetimeStart,
		@@ -520,6 +546,10 @@ public class ApfFilter {
		@GuardedBy("this")
		private byte[] mLastInstalledProgram;

		// For debugging only. How many times the program was updated since we started.
		@GuardedBy("this")
		private int mNumProgramUpdates;

		/**
		* Generate filter code to process ARP packets. Execution of this code ends in either the
		* DROP_LABEL or PASS_LABEL and does not fall off the end.
		@@ -724,6 +754,8 @@ public class ApfFilter {
		mLastTimeInstalledProgram = curTime();
		mLastInstalledProgramMinLifetime = programMinLifetime;
		mLastInstalledProgram = program;
		mNumProgramUpdates++;

		if (VDBG) {
		hexDump("Installing filter: ", program, program.length);
		}
		@@ -865,19 +897,20 @@ public class ApfFilter {
		}

		public synchronized void dump(IndentingPrintWriter pw) {
		pw.println("APF caps: " + mApfCapabilities);
		pw.println("Capabilities: " + mApfCapabilities);
		pw.println("Receive thread: " + (mReceiveThread != null ? "RUNNING" : "STOPPED"));
		pw.println("Multicast filtering: " + mMulticastFilter);
		pw.println("Multicast: " + (mMulticastFilter ? "DROP" : "ALLOW"));
		try {
		pw.println("IPv4 address: " + InetAddress.getByAddress(mIPv4Address));
		pw.println("IPv4 address: " + InetAddress.getByAddress(mIPv4Address).getHostAddress());
		} catch (UnknownHostException\|NullPointerException e) {}

		if (mLastTimeInstalledProgram == 0) {
		pw.println("No program installed.");
		return;
		}

		pw.println("Program updates: " + mNumProgramUpdates);
		pw.println(String.format(
		"Last program length %d, installed %ds ago, lifetime %d",
		"Last program length %d, installed %ds ago, lifetime %ds",
		mLastInstalledProgram.length, curTime() - mLastTimeInstalledProgram,
		mLastInstalledProgramMinLifetime));

		@@ -896,6 +929,7 @@ public class ApfFilter {
		}
		pw.decreaseIndent();
		}
		pw.decreaseIndent();

		if (DBG) {
		pw.println("Last program:");
		@@ -903,7 +937,5 @@ public class ApfFilter {
		pw.println(HexDump.toHexString(mLastInstalledProgram, false /* lowercase */));
		pw.decreaseIndent();
		}

		pw.decreaseIndent();
		}
		}