Merge "Ignore the checksum when comparing RAs for equality." into nyc-dev (12dbbc22) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/connectivity/ApfFilter.java

+21 −1

Original line number	Diff line number	Diff line
		@@ -155,6 +155,9 @@ public class ApfFilter {

		// From RFC4861:
		private static final int ICMP6_RA_HEADER_LEN = 16;
		private static final int ICMP6_RA_CHECKSUM_OFFSET =
		ETH_HEADER_LEN + IPV6_HEADER_LEN + 2;
		private static final int ICMP6_RA_CHECKSUM_LEN = 2;
		private static final int ICMP6_RA_OPTION_OFFSET =
		ETH_HEADER_LEN + IPV6_HEADER_LEN + ICMP6_RA_HEADER_LEN;
		private static final int ICMP6_RA_ROUTER_LIFETIME_OFFSET =
		@@ -216,9 +219,16 @@ public class ApfFilter {
		mPacket.clear();
		mLastSeen = curTime();

		// Ignore the checksum.
		int lastNonLifetimeStart = addNonLifetime(0,
		ICMP6_RA_CHECKSUM_OFFSET,
		ICMP6_RA_CHECKSUM_LEN);

		// Parse router lifetime
		int lastNonLifetimeStart = addNonLifetime(0, ICMP6_RA_ROUTER_LIFETIME_OFFSET,
		lastNonLifetimeStart = addNonLifetime(lastNonLifetimeStart,
		ICMP6_RA_ROUTER_LIFETIME_OFFSET,
		ICMP6_RA_ROUTER_LIFETIME_LEN);

		// Parse ICMP6 options
		mPacket.position(ICMP6_RA_OPTION_OFFSET);
		while (mPacket.hasRemaining()) {
		@@ -282,6 +292,12 @@ public class ApfFilter {
		ByteBuffer byteBuffer = ByteBuffer.wrap(packet);
		for (int i = 0; (i + 1) < mNonLifetimes.size(); i++) {
		int offset = mNonLifetimes.get(i).first + mNonLifetimes.get(i).second;

		// The checksum is in mNonLifetimes, but it's not a lifetime.
		if (offset == ICMP6_RA_CHECKSUM_OFFSET) {
		continue;
		}

		int lifetimeLength = mNonLifetimes.get(i+1).first - offset;
		long val;
		switch (lifetimeLength) {
		@@ -329,6 +345,10 @@ public class ApfFilter {
		if ((i + 1) < mNonLifetimes.size()) {
		Pair<Integer, Integer> nextNonLifetime = mNonLifetimes.get(i + 1);
		int offset = nonLifetime.first + nonLifetime.second;
		// Skip the checksum.
		if (offset == ICMP6_RA_CHECKSUM_OFFSET) {
		continue;
		}
		int length = nextNonLifetime.first - offset;
		switch (length) {
		case 4: gen.addLoad32(Register.R0, offset); break;