dnsjit/examples/replay.lua

#!/usr/bin/env dnsjit
local clock = require("dnsjit.lib.clock")
local log = require("dnsjit.core.log")
local getopt = require("dnsjit.lib.getopt").new({
    { "v", "verbose", 0, "Enable and increase verbosity for each time given", "?+" },
    { "R", "responses", false, "Wait for responses to the queries and print both", "?" },
    { "t", "tcp", false, "Use TCP instead of UDP", "?"},
    { "T", "tls", false, "Use TLS instead of UDP/TCP", "?"},
})
local pcap, host, port = unpack(getopt:parse())
if getopt:val("help") then
    getopt:usage()
    return
end
local v = getopt:val("v")
if v > 0 then
    log.enable("warning")
end
if v > 1 then
    log.enable("notice")
end
if v > 2 then
    log.enable("info")
end
if v > 3 then
    log.enable("debug")
end

if pcap == nil or host == nil or port == nil then
    print("usage: "..arg[1].." <pcap> <host> <port>")
    return
end

local ffi = require("ffi")

require("dnsjit.core.objects")
local input = require("dnsjit.input.mmpcap").new()
local layer = require("dnsjit.filter.layer").new()

input:open(pcap)
layer:producer(input)

local query = require("dnsjit.core.object.dns").new()
local response = require("dnsjit.core.object.dns").new()

local dnscli = require("dnsjit.output.dnscli")
local output
if getopt:val("t") then
    output = dnscli.new(dnscli.TCP)
    response.includes_dnslen = 1
elseif getopt:val("T") then
    output = dnscli.new(dnscli.TLS)
    response.includes_dnslen = 1
else
    output = dnscli.new(dnscli.UDP)
end
output:connect(host, port)

local printdns = false
if getopt:val("responses") then
    printdns = true
end

local prod, pctx = layer:produce()
local recv, rctx = output:receive()
local oprod, opctx = output:produce()
local start_sec, start_nsec = clock:monotonic()

while true do
    local obj = prod(pctx)
    if obj == nil then break end
    local pl = obj:cast()
    if obj:type() == "payload" and pl.len > 0 then
        query:reset()
        query.obj_prev = obj

        local trs = pl.obj_prev:cast()
        if trs:type() == "tcp" then
            query.includes_dnslen = 1
        else
            query.includes_dnslen = 0
        end

        if query:parse_header() == 0 and query.qr == 0 then
            recv(rctx, query:uncast())

            if printdns then
                print("query:")
                query:print()

                local pobj = oprod(opctx)
                if pobj == nil then
                    log.fatal("producer error")
                end
                local rpl = pobj:cast()
                if rpl.len == 0 then
                    print("timed out")
                else
                    response.obj_prev = pobj
                    print("response:")
                    response:print()
                end
            end
        end
    end
end

local end_sec, end_nsec = clock:monotonic()

local runtime = 0
if end_sec > start_sec then
    runtime = ((end_sec - start_sec) - 1) + ((1000000000 - start_nsec + end_nsec)/1000000000)
elseif end_sec == start_sec and end_nsec > start_nsec then
    runtime = (end_nsec - start_nsec) / 1000000000
end

print("runtime", runtime)
print("packets", input:packets(), input:packets()/runtime, "/pps")
print("queries", output:packets(), output:packets()/runtime, "/qps")
print("errors", output:errors())