blob: 03cc21f2ba3d182e9d202034ab0c32d24e540240 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
|
#!/usr/bin/env dnsjit
local pcap_in = arg[2]
local pcap_out = arg[3]
if pcap_in == nil or pcap_out == nil then
print("usage: "..arg[1].." <pcap in> <pcap out>")
return
end
local object = require("dnsjit.core.objects")
local input = require("dnsjit.input.pcap").new()
local layer = require("dnsjit.filter.layer").new()
local dns = require("dnsjit.core.object.dns").new()
local output = require("dnsjit.output.pcap").new()
input:open_offline(pcap_in)
layer:producer(input)
local producer, ctx = layer:produce()
output:open(pcap_out, input:linktype(), input:snaplen())
local receiver, rctx = output:receive()
local n = 0
while true do
local obj = producer(ctx)
if obj == nil then break end
local pl = obj:cast()
if obj:type() == "payload" and pl.len > 0 then
local protocol = obj.obj_prev
while protocol ~= nil do
if protocol.obj_type == object.UDP or protocol.obj_type == object.TCP then
break
end
protocol = protocol.obj_prev
end
dns:reset()
if protocol ~= nil and protocol.obj_type == object.TCP then
dns.includes_dnslen = 1
end
dns.obj_prev = obj
if dns:parse_header() == 0 then
receiver(rctx, obj)
n = n + 1
end
end
end
output:close()
print(n, "DNS packets dumped")
|
