36 lines
696 B
Lua
36 lines
696 B
Lua
local pcap = {}
|
|
local function uint32(n)
|
|
s = ""
|
|
for i = 3, 0, -1 do
|
|
s=s..string.char((n>>(8*i))%256)
|
|
end
|
|
return s
|
|
end
|
|
local function uint16(n)
|
|
s = ""
|
|
for i = 1, 0, -1 do
|
|
s=s..string.char((n>>(8*i))%256)
|
|
end
|
|
return s
|
|
end
|
|
|
|
function pcap.header(type)
|
|
local s=uint32(0xa1b2c3d4) -- magic number
|
|
s=s..uint16(2) -- major version
|
|
s=s..uint16(4) -- minor version
|
|
s=s..uint32(0) -- timezone
|
|
s=s..uint32(0) -- accuracy
|
|
s=s..uint32(2^16) -- snaplen
|
|
s=s..uint32(type or 147)
|
|
return s
|
|
end
|
|
function pcap.packet(d)
|
|
local s = uint32(os.time()) -- timestamp
|
|
s=s..uint32(0) -- usec
|
|
s=s..uint32(d:len()) -- included length
|
|
s=s..uint32(d:len()) -- actual length
|
|
return s..d
|
|
end
|
|
|
|
return pcap
|