87 lines
2.9 KiB
Ruby
87 lines
2.9 KiB
Ruby
# $Id: icmp.rb 14 2008-03-02 05:42:30Z warchild $
|
|
#
|
|
# Copyright (c) 2008, Jon Hart
|
|
# All rights reserved.
|
|
#
|
|
# Redistribution and use in source and binary forms, with or without
|
|
# modification, are permitted provided that the following conditions are met:
|
|
# * Redistributions of source code must retain the above copyright
|
|
# notice, this list of conditions and the following disclaimer.
|
|
# * Redistributions in binary form must reproduce the above copyright
|
|
# notice, this list of conditions and the following disclaimer in the
|
|
# documentation and/or other materials provided with the distribution.
|
|
# * Neither the name of the <organization> nor the
|
|
# names of its contributors may be used to endorse or promote products
|
|
# derived from this software without specific prior written permission.
|
|
#
|
|
# THIS SOFTWARE IS PROVIDED BY Jon Hart ``AS IS'' AND ANY
|
|
# EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
|
|
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
|
# DISCLAIMED. IN NO EVENT SHALL Jon Hart BE LIABLE FOR ANY
|
|
# DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
|
|
# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
|
|
# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
|
|
# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
|
|
# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
#
|
|
# Internet Control Message Protcol.
|
|
#
|
|
# RFC792 (http://www.faqs.org/rfcs/rfc792.html)
|
|
module Racket
|
|
class ICMP < RacketPart
|
|
ICMP_TYPE_ECHO_REPLY = 0
|
|
ICMP_TYPE_DESTINATION_UNREACHABLE = 3
|
|
ICMP_TYPE_SOURCE_QUENCH = 4
|
|
ICMP_TYPE_REDIRECT = 5
|
|
ICMP_TYPE_ECHO_REQUEST = 8
|
|
ICMP_TYPE_MOBILE_IP_ADVERTISEMENT = 9
|
|
ICMP_TYPE_ROUTER_SOLICITATION = 10
|
|
ICMP_TYPE_TIME_EXCEEDED = 11
|
|
ICMP_TYPE_PARAMETER_PROBLEM = 12
|
|
ICMP_TYPE_TIMESTAMP_REQUEST = 13
|
|
ICMP_TYPE_TIMESTAMP_REPLY = 14
|
|
ICMP_TYPE_INFO_REQUEST = 15
|
|
ICMP_TYPE_INFO_REPLY = 16
|
|
ICMP_TYPE_ADDRESS_MASK_REQUEST = 17
|
|
ICMP_TYPE_ADDRESS_MASK_REPLY = 18
|
|
|
|
# Type
|
|
unsigned :type, 8
|
|
# Code
|
|
unsigned :code, 8
|
|
# Checksum
|
|
unsigned :csum, 16
|
|
# ID
|
|
unsigned :id, 16
|
|
# Sequence number
|
|
unsigned :seq, 16
|
|
# Payload
|
|
rest :payload
|
|
|
|
# check the checksum for this ICMP packet
|
|
def checksum?
|
|
self.csum == compute_checksum
|
|
end
|
|
|
|
# compute and set the checksum for this ICMP packet
|
|
def checksum!
|
|
self.csum = compute_checksum
|
|
end
|
|
|
|
# 'fix' this ICMP packet up for sending.
|
|
# (really, just set the checksum)
|
|
def fix!
|
|
self.checksum!
|
|
end
|
|
|
|
private
|
|
def compute_checksum
|
|
# pseudo header used for checksum calculation as per RFC 768
|
|
pseudo = [ self.type, self.code, 0, self.id, self.seq, self.payload ]
|
|
L3::Misc.checksum(pseudo.pack("CCnnna*"))
|
|
end
|
|
end
|
|
end
|
|
# vim: set ts=2 et sw=2:
|