import org.jnetpcap.packet.JPacket; //导入依赖的package包/类
/**
 * In this function the packet is pseudonymization and checksums are recalculated as configured.
 *
 * @param packet the captured packet
 */
public void modifyPacket(JPacket packet) {
    if ((!DNS_ONLY) || isDns(packet)) {
        // If the original ip4 checksum is not valid, the checksum should not be modified.
        boolean originalChecksumValid = true;

        if (_pseudonymizerMap.containsKey(JProtocol.IP4) && packet.hasHeader(Ip4.ID)) {
            Ip4 ip4 = packet.getHeader(new Ip4());
            originalChecksumValid = ip4.isChecksumValid();
            pseudonymizeIP4(_pseudonymizerMap.get(JProtocol.IP4), ip4);
        } else if (_pseudonymizerMap.containsKey(JProtocol.IP6) && packet.hasHeader(Ip6.ID)) {
            Ip6 ip6 = packet.getHeader(new Ip6());
            pseudonymizeIP6(_pseudonymizerMap.get(JProtocol.IP6), ip6);
        }
        // Checksum updates.
        recalculateChecksums(packet, originalChecksumValid);
    }
}
 

import org.jnetpcap.packet.JPacket; //导入依赖的package包/类
/**
 * Recalculates the checksums as configured.
 *
 * @param packet the captured packet
 * @param originalChecksumValid boolean that holds whether the checksum was valid before modification.
 */
private void recalculateChecksums(final JPacket packet, final boolean originalChecksumValid) {
    for (int checksumType : _checksumList) {
        // The ip4 or ip6 checksum should be updated first.
        if (checksumType == Ip4.ID && originalChecksumValid) {
            if (packet.hasHeader(Ip4.ID)) {
                Ip4 ip4 = packet.getHeader(new Ip4());
                ip4.recalculateChecksum();
            }
        }
        if (checksumType == Udp.ID && packet.hasHeader(Udp.ID)) {
            recalulateUdpChecksum(packet);
        }
        if (checksumType == Tcp.ID && packet.hasHeader(Tcp.ID)) {
            Tcp tcp = packet.getHeader(new Tcp());
            tcp.recalculateChecksum();
        }
        if (checksumType == Icmp.ID && packet.hasHeader(Icmp.ID)) {
            Icmp icmp = packet.getHeader(new Icmp());
            icmp.recalculateChecksum();
        }
    }
}
 

import org.jnetpcap.packet.JPacket; //导入依赖的package包/类
/**
 * Bind2 http.
 * 
 * @param packet
 *          the packet
 * @param http
 *          the http
 * @return true, if successful
 */
@Bind(to = Http.class)
public static boolean bind2Http(JPacket packet, Http http) {
	Http.ContentType type = http.contentTypeEnum();
	switch (type) {
		case JPEG:
		case PNG:
		case GIF:
			return true;

		default:
			return false;
	}
}
 

import org.jnetpcap.packet.JPacket; //导入依赖的package包/类
/**
 * Check non static signature.
 * 
 * @param method
 *          the method
 */
private static void checkNonStaticSignature(final Method method) {

	final Class<?> declaringClass = method.getDeclaringClass();

	if (method.isAnnotationPresent(Bind.class) == false) {
		throw new AnnotatedMethodException(declaringClass,
		    "@Bind annotation missing for " + method.getName() + "()");
	}

	/*
	 * Now make sure it has the right signature of: <code>static int
	 * name(JBuffer, int)</code.
	 */
	final Class<?>[] sig = method.getParameterTypes();
	if (sig.length != 2 || sig[0] != JPacket.class
	    || sig[1].isAssignableFrom(JHeader.class)) {
		throw new AnnotatedMethodException(declaringClass,
		    "Invalid signature for " + method.getName() + "()");
	}

	if ((method.getModifiers() & Modifier.STATIC) != 0) {
		throw new AnnotatedMethodException(declaringClass, method.getName()
		    + "()" + " can not be declared static");
	}
}
 

import org.jnetpcap.packet.JPacket; //导入依赖的package包/类
public int analyzeFrame(JPacket packet, long referenceEpochTime){
	add("Frame "+Long.toString(packet.getFrameNumber()), 0);
	
	JCaptureHeader captureHeader = packet.getCaptureHeader();
	
	add("arrival time = "+new Timestamp(captureHeader.timestampInMillis()).toString(),1);
	
	double time= (double)(captureHeader.timestampInNanos())/1000000000.0;
	double timeSinceReference= (double)(captureHeader.timestampInNanos()-referenceEpochTime)/1000000000.0;
	add(String.format("epoch time = %1$.9f seconds",time),1);
	add(String.format("time since first frame = %1$.9f seconds",timeSinceReference),1);

	add("wire length = "+Integer.toString(captureHeader.wirelen()),1);
	add("capture length = "+Integer.toString(captureHeader.caplen()),1);
	
	return 1;
}
 

import org.jnetpcap.packet.JPacket; //导入依赖的package包/类
/**
 * Test j header is fragmented.
 */
public void testJHeaderIsFragmented() {
	JPacket packet = TestUtils.getPcapPacket(TestUtils.REASEMBLY, 1 - 1);
	Ethernet eth = new Ethernet();

	if (packet.hasHeader(eth)) {
		assertFalse(eth.isFragmented());
	}

	Ip4 ip = new Ip4();
	if (packet.hasHeader(ip)) {
		assertTrue(ip.isFragmented());
	}

	Icmp icmp = new Icmp();
	if (packet.hasHeader(icmp)) {
		assertTrue(ip.isFragmented());
	}

}
 

import org.jnetpcap.packet.JPacket; //导入依赖的package包/类
/**
 * Check signature.
 * 
 * @param method
 *          the method
 */
private static void checkSignature(final Method method) {

	final Class<?> declaringClass = method.getDeclaringClass();

	if (method.isAnnotationPresent(Bind.class) == false) {
		throw new AnnotatedMethodException(declaringClass,
		    "@Bind annotation missing for " + method.getName() + "()");
	}

	/*
	 * Now make sure it has the right signature of: <code>static int
	 * name(JBuffer, int)</code.
	 */
	final Class<?>[] sig = method.getParameterTypes();
	if (sig.length != 2 || sig[0] != JPacket.class
	    || sig[1].isAssignableFrom(JHeader.class)) {
		throw new AnnotatedMethodException(declaringClass,
		    "Invalid signature for " + method.getName() + "()");
	}

	if ((method.getModifiers() & Modifier.STATIC) == 0) {
		throw new AnnotatedMethodException(declaringClass, method.getName()
		    + "()" + " must be declared static");
	}
}
 

import org.jnetpcap.packet.JPacket; //导入依赖的package包/类
public int analyzePacket(JPacket packet, long referenceEpochTime){
	int maxLevel=analyzeFrame(packet, referenceEpochTime);
	
	final int headerCount = packet.getHeaderCount();
	for (int i=0;i<headerCount;++i){ 
		final int id = packet.getHeaderIdByIndex(i);
		final JHeader header = headerPool.getHeader(id);
		packet.getHeaderByIndex(i, header);
		
		int depth;
		if (id==JProtocol.PAYLOAD_ID){
			depth=analyzePayload(header);
		} else {
			depth=analyzeHeader(header);
		}
		
		if (depth>maxLevel){
			maxLevel=depth;
		}
	}
	
	return maxLevel;
}
 

import org.jnetpcap.packet.JPacket; //导入依赖的package包/类
/** 
 * @param packet
 * @param detail
 * @throws IOException
 * @see org.jnetpcap.packet.format.JFormatter#packetBefore(org.jnetpcap.packet.JPacket, org.jnetpcap.packet.format.JFormatter.Detail)
 */
@Override
public void packetBefore(JPacket packet, Detail detail) throws IOException {
	pad().format(LT + "packet");

	incLevel(PAD + PAD);

	pad().format("wirelen=\"%d\"", packet.getCaptureHeader().wirelen());
	pad().format("caplen=\"%d\"", packet.getCaptureHeader().caplen());

	if (frameIndex != -1) {
		pad().format("index=\"%d\"", frameIndex);
	}

	pad().format("timestamp=\"%s\"",
			new Timestamp(packet.getCaptureHeader().timestampInMillis()));
	pad().format("captureSeconds=\"%s\"", packet.getCaptureHeader().seconds());
	pad().format("captureNanoSeconds=\"%s\"" + GT,
			packet.getCaptureHeader().nanos());
	pad();

	decLevel();

	incLevel(PAD);
}
 

import org.jnetpcap.packet.JPacket; //导入依赖的package包/类
public void updateFrame_From_Packet(JPacket local_jPacket){
	
	IEC61850_GOOSE_Header goose_header = local_jPacket.getHeader( new IEC61850_GOOSE_Header());
	
	this.test = goose_header.test();
	this.ndsCom = goose_header.ndsCom();
	this.stNum = goose_header.stNum();
	this.sqNum = goose_header.sqNum();
	this.timeAllowedToLive = goose_header.timeAllowedToLive();
	
	// Reading the time in the header updates the time quality information
	this.utc_time = goose_header.utc();
	
	this.leapSecondsKnown = goose_header.leapSecondsKnown;
	this.clockFailure = goose_header.clockFailure;
	this.clockNotSynchronized = goose_header.clockNotSynchronized;
	this.timeAccuracy = goose_header.timeAccuracy;
	
	// We decode the data
	gooseData.decodeData(goose_header.gooseData());
}
 

import org.jnetpcap.packet.JPacket; //导入依赖的package包/类
/**
 * Within JNetPcap the UDP checksum recalculation does not work.
 * It is reimplemented here.
 *
 * @param packet packet to recalculate the udp checksum over.
 */
private void recalulateUdpChecksum(final JPacket packet) {
    final Udp udp = packet.getHeader(new Udp());
    udp.checksum(0); // The checksum is left out of the calculation but reset for correctness.
    final byte[] mergedBytes;
    if (packet.hasHeader(Ip4.ID)) {
        Ip4 ip4 = packet.getHeader(new Ip4());
        mergedBytes = constructIp4UdpChecksumByteArray(ip4, udp);
    } else {
        Ip6 ip6 = packet.getHeader(new Ip6());
        mergedBytes = constructIp6UdpChecksumByteArray(ip6, udp);
    }
    udp.checksum(ByteBuffer.wrap(calculateInternetChecksum(mergedBytes)).order(ByteOrder.BIG_ENDIAN).getShort());
}
 

import org.jnetpcap.packet.JPacket; //导入依赖的package包/类
/**
 * Check for DNS packets if required that only DNS packets should be handled.
 *
 * @param packet the captured packet.
 * @return true if the packet is a dns packet.
 */
private boolean isDns(final JPacket packet) {
    if (packet.hasHeader(Udp.ID)) {
        final Udp udp = packet.getHeader(new Udp());
        return (udp.source() == 53 || udp.destination() == 53);
    }
    else if (packet.hasHeader(Tcp.ID)) {
        final Tcp tcp = packet.getHeader(new Tcp());
        return (tcp.source() == 53 || tcp.destination() == 53);
    }
    return false;
}
 

import org.jnetpcap.packet.JPacket; //导入依赖的package包/类
public JPacket Generate_ArpReply(String MAC_SOURCE,String MAC_DESTINATION,String IP_SOURCE,String IP_DESTINATION){
	
	String Frame_WithoutCRC32=MAC_DESTINATION+MAC_SOURCE+DATA_TYPE+ARP_HEADER_REPLY+MAC_SOURCE+IP_SOURCE+MAC_DESTINATION+IP_DESTINATION+PADDING;
	
	JPacket arpRequest =new JMemoryPacket(JProtocol.ETHERNET_ID,Frame_WithoutCRC32);
	String CRC32=Integer.toHexString(Checksum.crc32IEEE802(arpRequest,0, arpRequest.size()));
	while(CRC32.length()<8){
		CRC32="0"+CRC32;
	}
	return new JMemoryPacket(JProtocol.ETHERNET_ID,Frame_WithoutCRC32+CRC32);
}
 

import org.jnetpcap.packet.JPacket; //导入依赖的package包/类
/**
 * Calculate checksum.
 * 
 * @return the long
 */
public int calculateChecksum() {
	if (getPostfixLength() < 4) {
		return 0;
	}

	final JPacket packet = getPacket();
	return Checksum.crc32IEEE802(packet, 0, getHeaderLength()
			+ getPayloadLength() + getPostfixLength() -4);
}
 

import org.jnetpcap.packet.JPacket; //导入依赖的package包/类
/**
 * Retrieves the header's checksum.
 * 
 * @return header's stored checksum
 */
@Field(length = 4 * BYTE, format = "%x", display = "FCS")
public int checksum() {
	if (getPostfixLength() < 4) {
		return 0;
	}

	final JPacket packet = getPacket();
	packet.order(ByteOrder.BIG_ENDIAN);
	return packet.getInt(packet.size() - 4);
}
 

import org.jnetpcap.packet.JPacket; //导入依赖的package包/类
/**
 * Retrieves the header's checksum.
 * 
 * @return header's stored checksum
 */
@Field(length = 4 * BYTE, format = "%x", display = "FCS")
public long checksum() {
	final JPacket packet = getPacket();
	packet.order(ByteOrder.BIG_ENDIAN);
	return packet.getUInt(getPostfixOffset());
}
 

import org.jnetpcap.packet.JPacket; //导入依赖的package包/类
/**
 * Calculates a checksum using protocol specification for a header. Checksums
 * for partial headers or fragmented packets (unless the protocol allows it)
 * are not calculated.
 * 
 * @return header's calculated checksum
 */
public long calculateChecksum() {
	if (getPostfixLength() < 4) {
		return 0L;
	}
	
	final JPacket packet = getPacket();
	return Checksum.crc32IEEE802(packet, 0, packet.size() - 4);
}
 

import org.jnetpcap.packet.JPacket; //导入依赖的package包/类
@Bind(to = Udp.class)
public static boolean bind2Udp(JPacket packet, Udp udp) {
	return udp.destination() == 1812 || udp.source() == 1812 // Server
			|| udp.destination() == 1813 || udp.source() == 1813 // Accounting
			|| udp.destination() == 3799 || udp.source() == 3799 // Authorization
			|| udp.destination() == 1646 || udp.source() == 1646; // Obsolete
}
 

import org.jnetpcap.packet.JPacket; //导入依赖的package包/类
/**
 * Formats a packet for output.
 * 
 * @param packet
 *          packet to format
 * @param detail
 *          detail level
 * @throws IOException
 *           any IO errors when sending data to default output device
 */
public void format(JPacket packet, Detail detail) throws IOException {

	if (packet == null) {
		packetNull(packet, detail);
		return;
	}

	packetBefore(packet, detail);

	final int count = packet.getHeaderCount();
	for (int i = 0; i < count; i++) {

		final int id = packet.getHeaderIdByIndex(i);
		if (id == JProtocol.PAYLOAD_ID && displayPayload == false) {
			continue;
		}

		try {
			final JHeader header = headers.getHeader(id);
			final Detail headerDetail =
					(detailsPerHeader[id] == null) ? detail : detailsPerHeader[id];

			packet.getHeaderByIndex(i, header);
			if (header.getLength() == 0) {
				continue;
			}

			format(header, headerDetail);
		} catch (UnregisteredHeaderException e) {
			throw new IllegalStateException(e); // Serious internal error
		}
	}

	packetAfter(packet, detail);
}
 

import org.jnetpcap.packet.JPacket; //导入依赖的package包/类
/** 
 * @param packet
 * @param detail
 * @throws IOException
 * @see org.jnetpcap.packet.format.JFormatter#packetAfter(org.jnetpcap.packet.JPacket, org.jnetpcap.packet.format.JFormatter.Detail)
 */
@Override
public void packetAfter(JPacket packet, Detail detail) throws IOException {

	decLevel();
	pad().format(LT + "/packet" + GT);

}