Class: Xlat::Pcap

Inherits:
Object
  • Object
show all
Defined in:
lib/xlat/pcap.rb

Constant Summary collapse

MAGIC =

nanosec timestamp

0xA1B23C4D
MAJOR = 
2
MINOR = 
4
LINKTYPE_RAW =

raw IP

101

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(io, snap_len: 0xffff) ⇒ Pcap

Returns a new instance of Pcap.



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# File 'lib/xlat/pcap.rb', line 7

def initialize(io, snap_len: 0xffff)
  @io = io
  @snap_len = snap_len

  write_header
end

Instance Attribute Details

#io ⇒ Object (readonly)

Returns the value of attribute io.



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# File 'lib/xlat/pcap.rb', line 5

def io
  @io
end

#snap_len ⇒ Object (readonly)

Returns the value of attribute snap_len.



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# File 'lib/xlat/pcap.rb', line 5

def snap_len
  @snap_len
end

Instance Method Details

#write(packet, ts: Time.now) ⇒ Object 



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# File 'lib/xlat/pcap.rb', line 33

def write(packet, ts: Time.now)
  caplen = [packet.size, @snap_len].min

  h = IO::Buffer.new(16)
  h.set_values(%i[u32 u32 u32 u32], 0, [
    ts.to_i,
    ts.nsec,
    caplen,
    packet.size,
  ])

  h.write(@io)
  packet.write(@io, caplen)
end