🌴 Sync 2026-03-05 23:51:42

luci-app-tcpdump/luasrc/controller/tcpdump.lua

@@ -0,0 +1,356 @@
+--[[
+LuCI - Lua Configuration Interface
+
+
+Copyright 2013-2014 Diego Manas <diegomanas.dev@gmail.com>
+
+Copyright (C) 2019, KFERMercer <iMercer@yeah.net>
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+$Id$
+
+2019-07-12  modified by KFERMercer <iMercer@yeah.com>:
+	format code
+
+]] --
+module("luci.controller.tcpdump", package.seeall)
+
+tcpdump_root_folder = "/tmp/tcpdump/"
+tcpdump_cap_folder = tcpdump_root_folder .. "cap/"
+tcpdump_filter_folder = tcpdump_root_folder .. "filter/"
+pid_file = tcpdump_root_folder .. "tcpdump.pid"
+log_file = tcpdump_root_folder .. "tcpdump.log"
+out_file = tcpdump_root_folder .. "tcpdump.out"
+sleep_file = tcpdump_root_folder .. "tcpdump.sleep"
+
+function index()
+	template("myapp-mymodule/helloworld")
+	entry({"admin", "network", "tcpdump"}, template("tcpdump"), _ "Tcpdump", 70).dependent =
+		false
+
+	page = entry({"admin", "network", "tcpdump", "capture_start"},
+				 call("capture_start"), nil)
+	page.leaf = true
+
+	page = entry({"admin", "network", "tcpdump", "capture_stop"},
+				 call("capture_stop"), nil)
+	page.leaf = true
+
+	page = entry({"admin", "network", "tcpdump", "update"}, call("update"), nil)
+	page.leaf = true
+
+	page = entry({"admin", "network", "tcpdump", "capture_get"},
+				 call("capture_get"), nil)
+	page.leaf = true
+
+	page = entry({"admin", "network", "tcpdump", "capture_remove"},
+				 call("capture_remove"), nil)
+	page.leaf = true
+
+end
+
+function param_check(ifname, stop_value, stop_unit, filter)
+	local check = false
+	local message = {}
+	-- Check interface
+	-- Check for empty interface
+	if ifname == nil or ifname == '' then
+		table.insert(message, "Interface name is null or blank.")
+	end
+	-- Check for existing interface
+	local nixio = require "nixio"
+	for k, v in ipairs(nixio.getifaddrs()) do
+		if v.family == "packet" then
+			if ifname == v.name then
+				check = true
+				break
+			end
+		end
+	end
+	-- Check special interface name "any"
+	if iface == 'any' then check = true end
+	-- ERROR interface name not found
+	if not check then
+		table.insert(message, "Interface does not exist or is not valid.")
+	end
+	-- Check stop condition value
+	if tonumber(stop_value) == nil then
+		check = false
+		table.insert(message, "Capture length parameter must be a number.")
+	end
+	-- Check stop condition flag
+	if stop_unit == nil then
+		check = false
+		table.insert(message, "Capture unit is null or blank.")
+	else
+		stop_unit = string.upper(stop_unit)
+		if stop_unit ~= "T" and stop_unit ~= "P" then
+			check = false
+			table.insert(message, "Capture unit must be Time(T) or packet(P).")
+		end
+	end
+	return check, message
+end
+
+function capture_start(ifname, stop_value, stop_unit, filter)
+	local active, pid = capture_active()
+	local res = {}
+	local cmd = {}
+	if active then
+		cmd["ok"] = false
+		cmd["msg"] = {"Previous capture is still ongoing!"}
+	else
+		local check, msg = param_check(ifname, stop_value, stop_unit, filter)
+		if not check then
+			cmd["ok"] = false
+			cmd["msg"] = msg
+		else
+			-- Create temporal folders
+			os.execute("mkdir -p " .. tcpdump_cap_folder)
+			os.execute("mkdir -p " .. tcpdump_filter_folder)
+			local prefix = "capture_" .. os.date("%Y-%m-%d_%H.%M.%S")
+			local pcap_file = tcpdump_cap_folder .. prefix .. ".pcap"
+			local filter_file = tcpdump_filter_folder .. prefix .. ".filter"
+			string_to_file(filter_file, filter)
+			string_to_file(out_file, prefix)
+			tcpdump_start(ifname, stop_value, stop_unit, filter_file, pcap_file)
+			res["filter"] = filter
+			cmd["ok"] = true
+			cmd["msg"] = {"Capture in progress.."}
+		end
+	end
+	res["cmd"] = cmd
+	res["capture"] = capture()
+	res["list"] = list()
+	luci.http.prepare_content("application/json")
+	luci.http.write_json(res)
+end
+
+function string_to_file(file, data)
+	if data == nil then data = "" end
+	local f = io.open(file, "w")
+	f:write(data)
+	f:close()
+end
+
+function tcpdump_start(ifname, stop_value, stop_unit, filter_file, pcap_file)
+	local cmd = "tcpdump -i %s -F %s -w %s"
+	cmd = string.format(cmd, ifname, filter_file, pcap_file)
+	-- Packet limit if required
+	if tonumber(stop_value) ~= 0 and stop_unit == "P" then
+		cmd = cmd .. " -c " .. stop_value
+	end
+	-- Mute output and record PID on pid_file
+	cmd = string.format("%s &> %s & echo $! > %s", cmd, log_file, pid_file)
+	os.execute(cmd)
+	-- Time limit if required
+	if tonumber(stop_value) ~= 0 and stop_unit == "T" then
+		local f = io.open(pid_file, "r")
+		if f ~= nil then
+			local pid = f:read()
+			f:close()
+			local t_out =
+				string.format("sleep %s && kill %s &", stop_value, pid)
+			os.execute(t_out)
+		end
+	end
+end
+
+function capture_stop()
+	local res = {}
+	local cmd = {}
+	local _, active, pid = capture()
+	if active then
+		luci.sys.process.signal(pid, 9)
+		cmd["ok"] = true
+		cmd["msg"] = {"Capture has been terminated"}
+	else
+		cmd["ok"] = false
+		cmd["msg"] = {"There was not active capture!"}
+	end
+	capture_cleanup()
+	res["cmd"] = cmd
+	res["capture"] = capture()
+	res["list"] = list()
+	luci.http.prepare_content("application/json")
+	luci.http.write_json(res)
+end
+
+function capture_active()
+	local f = io.open(pid_file, "r")
+	if f ~= nil then
+		pid = f:read()
+		f:close()
+		-- Check it is a legal PID and still alive
+		if tonumber(pid) ~= nil and luci.sys.process.signal(pid, 0) then
+			return true, pid
+		end
+	end
+	return false, nil
+end
+
+function capture_log()
+	local log
+	local f = io.open(log_file, "r")
+	if f ~= nil then
+		log = f:read("*all")
+		f:close()
+	else
+		log = ""
+	end
+	return log
+end
+
+function capture_name()
+	local cap_name = nil
+	local f = io.open(out_file, "r")
+	if f ~= nil then
+		cap_name = f:read()
+		f:close()
+	end
+	return cap_name
+end
+
+function capture()
+	local fs = require "nixio.fs"
+	local res = {}
+	local active, pid = capture_active()
+	local msg
+	res["active"] = active
+	res["log"] = capture_log()
+	if active then
+		res["msg"] = "Capture in progress.."
+		res["cap_name"] = capture_name()
+	elseif fs.access(pid_file) then
+		capture_cleanup()
+		res["msg"] = "Process seems to be dead, removing pid file!"
+	else
+		res["msg"] = "No capture in progress"
+	end
+	return res, active, pid
+end
+
+function capture_cleanup()
+	-- Careless file removal
+	os.remove(pid_file)
+	os.remove(log_file)
+	os.remove(out_file)
+	local f = io.open(sleep_file, "r")
+	if f ~= nil then
+		pid = f:read()
+		f:close()
+		-- Kill sleep process if still alive
+		if tonumber(pid) ~= nil or not luci.sys.process.signal(pid, 0) then
+			luci.sys.process.signal(pid, 9)
+		end
+	end
+	-- Careless file removal
+	os.remove(sleep_file)
+end
+
+function list_entries(cap_name)
+	local fs = require "nixio.fs"
+	local entries = {}
+	local name
+	local size
+	local mtime
+	local filter
+	local glob_str
+	if cap_name == nil then
+		glob_str = tcpdump_cap_folder .. "*.pcap"
+	else
+		glob_str = tcpdump_cap_folder .. cap_name .. ".pcap"
+	end
+	for file in fs.glob(glob_str) do
+		name = string.sub(fs.basename(file), 1, -6)
+		size = fs.stat(file, "size")
+		mtime = fs.stat(file, "ctime")
+		-- Figure out if there's an associated filter
+		if fs.access(tcpdump_filter_folder .. name .. ".filter") then
+			filter = true
+		else
+			filter = false
+		end
+		table.insert(entries,
+					 {name = name, size = size, mtime = mtime, filter = filter})
+	end
+	return entries
+end
+
+function list(cap_name)
+	res = {}
+	res["entries"] = list_entries(cap_name)
+	res["update"] = (cap_name ~= nil)
+	return res
+end
+
+function update(cap_name)
+	local res = {}
+	local cmd = {}
+	cmd["ok"] = true
+	res["cmd"] = cmd
+	res["capture"] = capture()
+	res["list"] = list(cap_name)
+	-- Build response
+	luci.http.prepare_content("application/json")
+	luci.http.write_json(res)
+end
+
+function pump_file(file, mime_str)
+	local fh = io.open(file)
+	local reader = luci.ltn12.source.file(fh)
+	luci.http.header("Content-Disposition", "attachment; filename=\"" ..
+						 nixio.fs.basename(file) .. "\"")
+	if mime_str ~= nil then
+		luci.http.prepare_content(mime_str)
+	else
+		luci.http.prepare_content("application/octet-stream")
+	end
+	luci.ltn12.pump.all(reader, luci.http.write)
+	fh:close()
+end
+
+function capture_get(file_type, cap_name)
+	if file_type == "all" then
+		local system = require "luci.controller.admin.system"
+		local tar_captures_cmd = "tar -c " .. tcpdump_cap_folder ..
+									 "*.pcap 2>/dev/null"
+		local reader = system.ltn12_popen(tar_captures_cmd)
+		luci.http.header('Content-Disposition',
+						 'attachment; filename="captures-%s.tar"' %
+							 {os.date("%Y-%m-%d_%H.%M.%S")})
+		luci.http.prepare_content("application/x-tar")
+		luci.ltn12.pump.all(reader, luci.http.write)
+	elseif file_type == "pcap" then
+		local file = tcpdump_cap_folder .. cap_name .. '.pcap'
+		pump_file(file)
+	elseif file_type == "filter" then
+		local file = tcpdump_filter_folder .. cap_name .. '.filter'
+		pump_file(file, "text/plain")
+	else
+		-- TODO
+	end
+end
+
+function capture_remove(cap_name)
+	if cap_name == 'all' then
+		local fs = require "nixio.fs"
+		for file in fs.glob(tcpdump_cap_folder .. "*.pcap") do
+			os.remove(file)
+		end
+		for file in fs.glob(tcpdump_filter_folder .. "*.filter") do
+			os.remove(file)
+		end
+	else
+		-- Remove both, capture and filter file
+		os.remove(tcpdump_cap_folder .. cap_name .. ".pcap")
+		os.remove(tcpdump_filter_folder .. cap_name .. ".filter")
+	end
+	-- Return current status and list
+	update()
+end