Improve the resiliency of the packet deserialization code.
Packet deserializers now check for malformed input while reading the byte
stream. Deserializers are re-implemented as functions that take a byte array
and return a packet object. The old IPacket.deserialize(...) methods have been
deprecated with the goal of eventually moving to immutable packet objects.
Unit tests have been implemented for all Deserializer functions.
ONOS-1589
Change-Id: I9073d5e6e7991e15d43830cfd810989256b71c56
diff --git a/utils/misc/src/main/java/org/onlab/packet/IPv4.java b/utils/misc/src/main/java/org/onlab/packet/IPv4.java
index d1563eb..0d75245 100644
--- a/utils/misc/src/main/java/org/onlab/packet/IPv4.java
+++ b/utils/misc/src/main/java/org/onlab/packet/IPv4.java
@@ -25,6 +25,8 @@
import java.util.HashMap;
import java.util.Map;
+import static org.onlab.packet.PacketUtils.*;
+
/**
*
*/
@@ -32,19 +34,21 @@
public static final byte PROTOCOL_ICMP = 0x1;
public static final byte PROTOCOL_TCP = 0x6;
public static final byte PROTOCOL_UDP = 0x11;
- public static final Map<Byte, Class<? extends IPacket>> PROTOCOL_CLASS_MAP =
+ public static final Map<Byte, Deserializer<? extends IPacket>> PROTOCOL_DESERIALIZER_MAP =
new HashMap<>();
static {
- IPv4.PROTOCOL_CLASS_MAP.put(IPv4.PROTOCOL_ICMP, ICMP.class);
- IPv4.PROTOCOL_CLASS_MAP.put(IPv4.PROTOCOL_TCP, TCP.class);
- IPv4.PROTOCOL_CLASS_MAP.put(IPv4.PROTOCOL_UDP, UDP.class);
+ IPv4.PROTOCOL_DESERIALIZER_MAP.put(IPv4.PROTOCOL_ICMP, ICMP.deserializer());
+ IPv4.PROTOCOL_DESERIALIZER_MAP.put(IPv4.PROTOCOL_TCP, TCP.deserializer());
+ IPv4.PROTOCOL_DESERIALIZER_MAP.put(IPv4.PROTOCOL_UDP, UDP.deserializer());
}
private static final byte DSCP_MASK = 0x3f;
private static final byte DSCP_OFFSET = 2;
private static final byte ECN_MASK = 0x3;
+ private static final short HEADER_LENGTH = 20;
+
protected byte version;
protected byte headerLength;
protected byte diffServ;
@@ -414,7 +418,7 @@
@Override
public IPacket deserialize(final byte[] data, final int offset,
- final int length) {
+ final int length) {
final ByteBuffer bb = ByteBuffer.wrap(data, offset, length);
short sscratch;
@@ -439,29 +443,26 @@
bb.get(this.options);
}
- IPacket payload;
- if (IPv4.PROTOCOL_CLASS_MAP.containsKey(this.protocol)) {
- final Class<? extends IPacket> clazz = IPv4.PROTOCOL_CLASS_MAP
- .get(this.protocol);
- try {
- payload = clazz.newInstance();
- } catch (final Exception e) {
- throw new RuntimeException(
- "Error parsing payload for IPv4 packet", e);
- }
- } else {
- payload = new Data();
- }
- this.payload = payload.deserialize(data, bb.position(),
- bb.limit() - bb.position());
- this.payload.setParent(this);
-
if (this.totalLength != length) {
this.isTruncated = true;
} else {
this.isTruncated = false;
}
+ Deserializer<? extends IPacket> deserializer;
+ if (IPv4.PROTOCOL_DESERIALIZER_MAP.containsKey(this.protocol)) {
+ deserializer = IPv4.PROTOCOL_DESERIALIZER_MAP.get(this.protocol);
+ } else {
+ deserializer = Data.deserializer();
+ }
+ try {
+ this.payload = deserializer.deserialize(data, bb.position(),
+ bb.limit() - bb.position());
+ this.payload.setParent(this);
+ } catch (DeserializationException e) {
+ return this;
+ }
+
return this;
}
@@ -669,4 +670,60 @@
}
return true;
}
+
+ /**
+ * Deserializer function for IPv4 packets.
+ *
+ * @return deserializer function
+ */
+ public static Deserializer<IPv4> deserializer() {
+ return (data, offset, length) -> {
+ checkInput(data, offset, length, HEADER_LENGTH);
+
+ IPv4 ipv4 = new IPv4();
+
+ final ByteBuffer bb = ByteBuffer.wrap(data, offset, length);
+
+ byte versionByte = bb.get();
+ ipv4.headerLength = (byte) (versionByte & 0xf);
+ ipv4.setVersion((byte) (versionByte >> 4 & 0xf));
+ ipv4.setDiffServ(bb.get());
+ ipv4.totalLength = bb.getShort();
+ ipv4.identification = bb.getShort();
+ short flagsFragment = bb.getShort();
+ ipv4.flags = (byte) (flagsFragment >> 13 & 0x7);
+ ipv4.fragmentOffset = (short) (flagsFragment & 0x1fff);
+ ipv4.ttl = bb.get();
+ ipv4.protocol = bb.get();
+ ipv4.checksum = bb.getShort();
+ ipv4.sourceAddress = bb.getInt();
+ ipv4.destinationAddress = bb.getInt();
+
+ if (ipv4.headerLength > 5) {
+ checkHeaderLength(length, ipv4.headerLength * 4);
+
+ int optionsLength = (ipv4.headerLength - 5) * 4;
+ ipv4.options = new byte[optionsLength];
+ bb.get(ipv4.options);
+ }
+
+ Deserializer<? extends IPacket> deserializer;
+ if (IPv4.PROTOCOL_DESERIALIZER_MAP.containsKey(ipv4.protocol)) {
+ deserializer = IPv4.PROTOCOL_DESERIALIZER_MAP.get(ipv4.protocol);
+ } else {
+ deserializer = Data.deserializer();
+ }
+ ipv4.payload = deserializer.deserialize(data, bb.position(),
+ bb.limit() - bb.position());
+ ipv4.payload.setParent(ipv4);
+
+ if (ipv4.totalLength != length) {
+ ipv4.isTruncated = true;
+ } else {
+ ipv4.isTruncated = false;
+ }
+
+ return ipv4;
+ };
+ }
}