Sha256: c06997872d249089037e24d2ee1f5ff2355d7ce570d1a2587ab371898104e2fe
Contents?: true
Size: 1.81 KB
Versions: 17
Compression:
Stored size: 1.81 KB
Contents
# http://www.mudynamics.com
# http://labs.mudynamics.com
# http://www.pcapr.net
module Mu
class Pcap
class UDP < Packet
attr_accessor :src_port, :dst_port
def initialize src_port=0, dst_port=0
super()
@src_port = src_port
@dst_port = dst_port
end
def flow_id
return [:udp, @src_port, @dst_port]
end
FMT_nnnn = 'nnnn'
def self.from_bytes bytes
bytes_length = bytes.length
bytes_length >= 8 or
raise ParseError, "Truncated UDP header: expected 8 bytes, got #{bytes_length} bytes"
sport, dport, length, checksum = bytes.unpack(FMT_nnnn)
bytes_length >= length or
raise ParseError, "Truncated UDP packet: expected #{length} bytes, got #{bytes_length} bytes"
udp = UDP.new sport, dport
udp.payload_raw = bytes[8..-1]
udp.payload = bytes[8..length]
return udp
end
def write io, ip
length = @payload.length
length_8 = length + 8
if length_8 > 65535
Pcap.warning "UDP payload is too large"
end
pseudo_header = ip.pseudo_header length_8
header = [@src_port, @dst_port, length_8, 0] \
.pack FMT_nnnn
checksum = IP.checksum(pseudo_header + header + @payload)
header = [@src_port, @dst_port, length_8, checksum] \
.pack FMT_nnnn
io.write header
io.write @payload
end
def self.udp? packet
return packet.is_a?(Ethernet) &&
packet.payload.is_a?(IP) &&
packet.payload.payload.is_a?(UDP)
end
def to_s
return "udp(%d, %d, %s)" % [@src_port, @dst_port, @payload.inspect]
end
def == other
return super &&
self.src_port == other.src_port &&
self.dst_port == other.dst_port
end
end
end
end
Version data entries
17 entries across 17 versions & 2 rubygems