package org.opendaylight.controller.sal.packet;
-import java.net.InetAddress;
-import java.net.UnknownHostException;
+import java.util.Arrays;
import java.util.Map;
import java.util.Map.Entry;
* Abstract class which represents the generic network packet object It provides
* the basic methods which are common for all the packets, like serialize and
* deserialize
- *
- *
*/
public abstract class Packet {
protected Packet parent;
// The packet encapsulated by this packet
protected Packet payload;
+ // The unparsed raw payload carried by this packet
+ protected byte[] rawPayload;
// Bit coordinates of packet header fields
protected Map<String, Pair<Integer, Integer>> hdrFieldCoordMap;
// Header fields values: Map<FieldName,Value>
public Packet(boolean writeAccess) {
this.writeAccess = writeAccess;
- this.corrupted = false;
+ corrupted = false;
}
public Packet getParent() {
/**
* This method deserializes the data bits obtained from the wire into the
* respective header and payload which are of type Packet
- *
+ *
* @param byte[] data - data from wire to deserialize
* @param int bitOffset bit position where packet header starts in data
* array
* @return Packet
* @throws PacketException
*/
-
public Packet deserialize(byte[] data, int bitOffset, int size)
throws PacketException {
- String hdrField;
- Integer startOffset = 0, numBits = 0;
- byte[] hdrFieldBytes;
+ // Deserialize the header fields one by one
+ int startOffset = 0, numBits = 0;
for (Entry<String, Pair<Integer, Integer>> pairs : hdrFieldCoordMap
.entrySet()) {
- hdrField = pairs.getKey();
+ String hdrField = pairs.getKey();
startOffset = bitOffset + this.getfieldOffset(hdrField);
numBits = this.getfieldnumBits(hdrField);
+ byte[] hdrFieldBytes = null;
try {
hdrFieldBytes = BitBufferHelper.getBits(data, startOffset,
numBits);
} catch (BufferException e) {
throw new PacketException(e.getMessage());
}
+
/*
* Store the raw read value, checks the payload type and set the
* payloadClass accordingly
*/
+ this.setHeaderField(hdrField, hdrFieldBytes);
+
if (logger.isTraceEnabled()) {
- logger.trace("{}: {}: {} (offset {} bitsize {})",
- new Object[] { this.getClass().getSimpleName(), hdrField,
- HexEncode.bytesToHexString(hdrFieldBytes),
- startOffset, numBits });
+ logger.trace("{}: {}: {} (offset {} bitsize {})",
+ new Object[] { this.getClass().getSimpleName(), hdrField,
+ HexEncode.bytesToHexString(hdrFieldBytes),
+ startOffset, numBits });
}
-
- this.setHeaderField(hdrField, hdrFieldBytes);
}
- postDeserializeCustomOperation(data, startOffset);
-
+ // Deserialize the payload now
int payloadStart = startOffset + numBits;
- // int payloadSize = size - payloadStart;
int payloadSize = data.length * NetUtils.NumBitsInAByte - payloadStart;
if (payloadClass != null) {
payload.deserialize(data, payloadStart, payloadSize);
payload.setParent(this);
} else {
- // For now let's discard unparsable payload
+ /*
+ * The payload class was not set, it means no class for parsing
+ * this payload is present. Let's store the raw payload if any.
+ */
+ int start = payloadStart / NetUtils.NumBitsInAByte;
+ int stop = start + payloadSize / NetUtils.NumBitsInAByte;
+ rawPayload = Arrays.copyOfRange(data, start, stop);
}
+
+
+ // Take care of computation that can be done only after deserialization
+ postDeserializeCustomOperation(data, payloadStart - getHeaderSize());
+
return this;
}
/**
- * This method serializes the header and payload bytes from the respective
+ * This method serializes the header and payload from the respective
* packet class, into a single stream of bytes to be sent on the wire
- *
- * @return byte[] - serialized bytes
+ *
+ * @return The byte array representing the serialized Packet
* @throws PacketException
*/
-
public byte[] serialize() throws PacketException {
- byte[] payloadBytes = null;
- int payloadSize = 0;
- int headerSize = this.getHeaderSize();
- int payloadByteOffset = headerSize / NetUtils.NumBitsInAByte;
- int size = 0;
+ // Acquire or compute the serialized payload
+ byte[] payloadBytes = null;
if (payload != null) {
payloadBytes = payload.serialize();
- payloadSize = payloadBytes.length * NetUtils.NumBitsInAByte;
+ } else if (rawPayload != null) {
+ payloadBytes = rawPayload;
}
+ int payloadSize = (payloadBytes == null) ? 0 : payloadBytes.length;
- size = headerSize + payloadSize;
- int length = size / NetUtils.NumBitsInAByte;
- byte headerBytes[] = new byte[length];
-
- if (payload != null) {
- System.arraycopy(payloadBytes, 0, headerBytes, payloadByteOffset,
- payloadBytes.length);
+ // Allocate the buffer to contain the full (header + payload) packet
+ int headerSize = this.getHeaderSize() / NetUtils.NumBitsInAByte;
+ byte packetBytes[] = new byte[headerSize + payloadSize];
+ if (payloadBytes != null) {
+ System.arraycopy(payloadBytes, 0, packetBytes, headerSize, payloadSize);
}
- String field;
- byte[] fieldBytes;
- Integer startOffset, numBits;
-
+ // Serialize this packet header, field by field
for (Map.Entry<String, Pair<Integer, Integer>> pairs : hdrFieldCoordMap
.entrySet()) {
- field = pairs.getKey();
- fieldBytes = hdrFieldsMap.get(field);
+ String field = pairs.getKey();
+ byte[] fieldBytes = hdrFieldsMap.get(field);
// Let's skip optional fields when not set
if (fieldBytes != null) {
- startOffset = this.getfieldOffset(field);
- numBits = this.getfieldnumBits(field);
try {
- BitBufferHelper.setBytes(headerBytes, fieldBytes,
- startOffset, numBits);
+ BitBufferHelper.setBytes(packetBytes, fieldBytes,
+ getfieldOffset(field), getfieldnumBits(field));
} catch (BufferException e) {
throw new PacketException(e.getMessage());
}
}
}
- postSerializeCustomOperation(headerBytes);
+
+ // Perform post serialize operations (like checksum computation)
+ postSerializeCustomOperation(packetBytes);
if (logger.isTraceEnabled()) {
- logger.trace("{}: {}", this.getClass().getSimpleName(),
- HexEncode.bytesToHexString(headerBytes));
+ logger.trace("{}: {}", this.getClass().getSimpleName(),
+ HexEncode.bytesToHexString(packetBytes));
}
- return headerBytes;
+
+ return packetBytes;
}
/**
* byte stream which cannot be done or cannot be done efficiently during the
* normal Packet.serialize() path. An example is the checksum computation
* for IPv4
- *
+ *
* @param byte[] - serialized bytes
* @throws PacketException
*/
/**
* This method re-computes the checksum of the bits received on the wire and
* validates it with the checksum in the bits received Since the computation
- * of checksum varies based on the protocol, this method is overridden
- * Currently only IPv4 does checksum computation and validation TCP and UDP
- * need to implement these if required
- *
- * @param byte[] data
- * @param int endBitOffset
+ * of checksum varies based on the protocol, this method is overridden.
+ * Currently only IPv4 and ICMP do checksum computation and validation. TCP
+ * and UDP need to implement these if required.
+ *
+ * @param byte[] data The byte stream representing the Ethernet frame
+ * @param int startBitOffset The bit offset from where the byte array corresponding to this Packet starts in the frame
* @throws PacketException
*/
- protected void postDeserializeCustomOperation(byte[] data, int endBitOffset)
+ protected void postDeserializeCustomOperation(byte[] data, int startBitOffset)
throws PacketException {
// no op
}
/**
* Gets the header length in bits
- *
+ *
* @return int the header length in bits
*/
public int getHeaderSize() {
* This method fetches the start bit offset for header field specified by
* 'fieldname'. The offset is present in the hdrFieldCoordMap of the
* respective packet class
- *
+ *
* @param String
* fieldName
* @return Integer - startOffset of the requested field
*/
public int getfieldOffset(String fieldName) {
- return (((Pair<Integer, Integer>) hdrFieldCoordMap.get(fieldName))
- .getLeft());
+ return hdrFieldCoordMap.get(fieldName).getLeft();
}
/**
* This method fetches the number of bits for header field specified by
* 'fieldname'. The numBits are present in the hdrFieldCoordMap of the
* respective packet class
- *
+ *
* @param String
* fieldName
* @return Integer - number of bits of the requested field
*/
public int getfieldnumBits(String fieldName) {
- return (((Pair<Integer, Integer>) hdrFieldCoordMap.get(fieldName))
- .getRight());
+ return hdrFieldCoordMap.get(fieldName).getRight();
}
@Override
public String toString() {
- StringBuffer ret = new StringBuffer();
- for (Map.Entry<String, byte[]> entry : hdrFieldsMap.entrySet()) {
- ret.append(entry.getKey() + ": ");
- if (entry.getValue().length == 6) {
- ret.append(HexEncode.bytesToHexString(entry.getValue()) + " ");
- } else if (entry.getValue().length == 4) {
- try {
- ret.append(InetAddress.getByAddress(entry.getValue())
- .getHostAddress() + " ");
- } catch (UnknownHostException e) {
- logger.error("", e);
- }
- } else {
- ret.append(((Long) BitBufferHelper.getLong(entry.getValue()))
- .toString() + " ");
- }
+ StringBuilder ret = new StringBuilder();
+ ret.append(this.getClass().getSimpleName());
+ ret.append(": [");
+ for (String field : hdrFieldCoordMap.keySet()) {
+ byte[] value = hdrFieldsMap.get(field);
+ ret.append(field);
+ ret.append(": ");
+ ret.append(HexEncode.bytesToHexString(value));
+ ret.append(", ");
}
+ ret.replace(ret.length()-2, ret.length()-1, "]");
return ret.toString();
}
/**
- * Returns true if the packet is corrupted
- *
- * @return boolean
+ * Returns the raw payload carried by this packet in case payload was not
+ * parsed. Caller can call this function in case the getPaylod() returns null.
+ *
+ * @return The raw payload if not parsable as an array of bytes, null otherwise
+ */
+ public byte[] getRawPayload() {
+ return rawPayload;
+ }
+
+ /**
+ * Set a raw payload in the packet class
+ *
+ * @param payload The raw payload as byte array
+ */
+ public void setRawPayload(byte[] payload) {
+ this.rawPayload = Arrays.copyOf(payload, payload.length);
+ }
+
+ /**
+ * Return whether the deserialized packet is to be considered corrupted.
+ * This is the case when the checksum computed after reconstructing the
+ * packet received from wire is not equal to the checksum read from the
+ * stream. For the Packet class which do not have a checksum field, this
+ * function will always return false.
+ *
+ *
+ * @return true if the deserialized packet's recomputed checksum is not
+ * equal to the packet carried checksum
*/
- protected boolean isPacketCorrupted() {
+ public boolean isCorrupted() {
return corrupted;
}
+
+ @Override
+ public int hashCode() {
+ final int prime = 31;
+ int result = super.hashCode();
+ result = prime * result
+ + ((this.hdrFieldsMap == null) ? 0 : hdrFieldsMap.hashCode());
+ return result;
+ }
+
+ @Override
+ public boolean equals(Object obj) {
+ if (this == obj) {
+ return true;
+ }
+ if (getClass() != obj.getClass()) {
+ return false;
+ }
+ Packet other = (Packet) obj;
+ if (hdrFieldsMap == other.hdrFieldsMap) {
+ return true;
+ }
+ if (hdrFieldsMap == null || other.hdrFieldsMap == null) {
+ return false;
+ }
+ if (hdrFieldsMap != null && other.hdrFieldsMap != null) {
+ for (String field : hdrFieldsMap.keySet()) {
+ if (!Arrays.equals(hdrFieldsMap.get(field), other.hdrFieldsMap.get(field))) {
+ return false;
+ }
+ }
+ } else {
+ return false;
+ }
+ return true;
+ }
+
}
Code Review / controller.git / blobdiff