Package org.opennms.protocols.icmp

Class ErrorMessage

java.lang.Object

org.opennms.protocols.icmp.ICMPHeader

org.opennms.protocols.icmp.ErrorMessage

public class ErrorMessage
extends ICMPHeader

Defines the default error handler object for processing ICMP error messages. All error messages follow the same format. The first 8 bytes is the ICMP header. Immediantly after the ICMP header is the IP packet in error, including any option data. After the IP header is the first 8 bytes of protocol data. This is enough to hold a UDP header or the first 8 bytes of a TCP header.

Author:

Brian Weaver

Field Summary

Fields inherited from class org.opennms.protocols.icmp.ICMPHeader

CODE_BAD_IP_HEADER, CODE_COMMUNICATIONS_ADMIN_PROHIBITIED, CODE_DESTINATION_HOST_ADMIN_PROHIBITED, CODE_DESTINATION_HOST_UNKNOWN, CODE_DESTINATION_NETWORK_ADMIN_PROHIBITED, CODE_DESTINATION_NETWORK_UNKNOWN, CODE_FRAGMENTATION_NEEDED, CODE_HOST_PRECEDENCE_VIOLATION, CODE_HOST_UNREACHABLE, CODE_HOST_UNREACHABLE_FOR_TOS, CODE_NETWORK_UNREACHABLE, CODE_NETWORK_UNREACHABLE_FOR_TOS, CODE_PORT_UNREACHABLE, CODE_PRECEDENCE_CUTOFF_IN_EFFECT, CODE_PROTOCOL_UNREACHABLE, CODE_REDIRECT_FOR_HOST, CODE_REDIRECT_FOR_NETWORK, CODE_REDIRECT_FOR_TYPE_OF_SERVICE_AND_HOST, CODE_REDIRECT_FOR_TYPE_OF_SERVICE_AND_NETWORK, CODE_REQUIRED_OPTION_MISSING, CODE_SOURCE_HOST_ISOLATED, CODE_SOURCE_ROUTE_FAILED, CODE_TTL_EQ_ZERO_IN_REASSEMBLY, CODE_TTL_EQ_ZERO_IN_TRANSIT, TYPE_ADDRESS_MASK_REPLY, TYPE_ADDRESS_MASK_REQUEST, TYPE_DESTINATION_UNREACHABLE, TYPE_ECHO_REPLY, TYPE_ECHO_REQUEST, TYPE_INFORMATION_REPLY, TYPE_INFORMATION_REQUEST, TYPE_PARAMETER_PROBLEM, TYPE_REDIRECT, TYPE_ROUTER_ADVERTISEMENT, TYPE_ROUTER_SOLICITATION, TYPE_SOURCE_QUENCH, TYPE_TIME_EXCEEDED, TYPE_TIMESTAMP_REPLY, TYPE_TIMESTAMP_REQUEST

Constructor Summary

Constructors

Modifier	Constructor	Description
	ErrorMessage(byte[] buf, int offset)	Creates a new ICMP timestamp reply from the spcified data at the specific offset.
protected	ErrorMessage(byte type, byte code)	Creates a new ICMP Error Message object.

Method Summary

Modifier and Type	Method	Description
final IPHeader	getIPHeader()	Used to access the IP Header that caused the ICMP error message to be generated.
final byte[]	getProtocolData()	Retreives the 8 bytes of protocol data that caused the error.
final int	loadFromBuffer(byte[] buf, int offset)	Reads the ICMP Address Mask Reqeust from the specified buffer and sets the internal fields equal to the data.
protected void	setIPHeader(IPHeader hdr)	Sets the IP header in error.
protected void	setProtocolData(byte[] pd)	Sets the protocol data that caused the error.

Methods inherited from class org.opennms.protocols.icmp.ICMPHeader

byteToInt, byteToShort, computeChecksum, computeChecksum, getChecksum, getCode, getHeaderSize, getIdentity, getNetworkSize, getSequenceId, getType, isEchoReply, isEchoRequest, nextSequenceId, setChecksum, setCode, setIdentity, setNextSequenceId, setSequenceId, setType, storeToBuffer, toBytes

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

ErrorMessage

protected ErrorMessage(byte type,
 byte code)

Creates a new ICMP Error Message object.

Parameters:

type - The ICMP type.

code - The specific code for the message.

ErrorMessage

public ErrorMessage(byte[] buf,
 int offset)

Creates a new ICMP timestamp reply from the spcified data at the specific offset.

Parameters:

buf - The buffer containing the data.

offset - The start of the icmp data.

Throws:

IndexOutOfBoundsException - Thrown if there is not sufficent data in the buffer.

Method Details

loadFromBuffer

public final int loadFromBuffer(byte[] buf,
 int offset)

Reads the ICMP Address Mask Reqeust from the specified buffer and sets the internal fields equal to the data. If the buffer does not have sufficent data to restore the header then an IndexOutOfBoundsException is thrown by the method. If the buffer does not contain an address mask reqeust then an IllegalArgumentException is thrown.

Overrides:

loadFromBuffer in class ICMPHeader

Parameters:

buf - The buffer to read the data from.

offset - The offset to start reading data.

Returns:

The new offset after reading the data.

Throws:

IndexOutOfBoundsException - Thrown if there is not sufficent data in the buffer.

getIPHeader

public final IPHeader getIPHeader()

Used to access the IP Header that caused the ICMP error message to be generated.

Returns:

The IP Header in error.

setIPHeader

protected void setIPHeader(IPHeader hdr)

Sets the IP header in error.

Parameters:

hdr - The IP header in error

getProtocolData

public final byte[] getProtocolData()

Retreives the 8 bytes of protocol data that caused the error.

Returns:

The first 8 bytes of the packet in error.

setProtocolData

protected void setProtocolData(byte[] pd)

Sets the protocol data that caused the error.

Parameters:

pd - The 8 bytes of protocol data.

Throws:

IndexOutOfBoundsException - Thrown when pd.length is less than 8.

IllegalArgumentException - Thrown when pd.length is greater than 8.