From 7634edc3381bbea5a2035331e70a091bdeccf822 Mon Sep 17 00:00:00 2001
From: Christian Muehlhaeuser <muesli@gmail.com>
Date: Wed, 21 Feb 2018 07:31:13 +0100
Subject: [PATCH 1/2] Parse parameters and flags with lua_cliargs

---
 README.md         |  4 ++--
 frivpn_client.lua | 22 ++++++++++++++++++++--
 2 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/README.md b/README.md
index 2a13f2f..1d432aa 100644
--- a/README.md
+++ b/README.md
@@ -23,13 +23,13 @@ in the best possible VPN bandwidth and throughput.
 ### Debian (stretch)
 
 ```
-# apt install build-essential lua5.2 lua5.2-dev lua-posix lua-luaossl lua-cqueues libssl-dev liblzo2-dev
+# apt install build-essential lua5.2 lua5.2-dev lua-cliargs lua-posix lua-luaossl lua-cqueues libssl-dev liblzo2-dev
 ```
 
 ### Ubuntu 17.10
 
 ```
-# apt install build-essential lua liblua5.2-dev lua-posix lua-luaossl lua-cqueues libssl-dev liblzo2-dev
+# apt install build-essential lua liblua5.2-dev lua-cliargs lua-posix lua-luaossl lua-cqueues libssl-dev liblzo2-dev
 ```
 
 ## Build it
diff --git a/frivpn_client.lua b/frivpn_client.lua
index adac912..d6f843b 100755
--- a/frivpn_client.lua
+++ b/frivpn_client.lua
@@ -12,6 +12,7 @@ local x509 = require "openssl.x509"
 local castore = require "openssl.x509.store"
 local pkey = require "openssl.pkey"
 local posix = require "posix"
+local cli = require "cliargs"
 
 require "libfrivpn"
 require "utils"
@@ -464,6 +465,11 @@ function vpn:connect(host, port)
 	end
 end
 
+local function print_version()
+	print("frivpn_client: version 0.0.1")
+	os.exit(0)
+end
+
 function ssl_preload()
 	local a, b = csock.pair()
 	-- do a dummy checktls so cqueues socket loads & keeps the ossl module
@@ -475,13 +481,25 @@ end
 
 ssl_preload()
 
+-- cliargs handling
+cli:set_name("frivpn_client")
+cli:argument("CONFIG", "config module to load (e.g. configs/ipredator)")
+cli:flag("-v, --version", "print frivpn's version", print_version)
+cli:flag("--notun", "creates no tun device")
+
+local args, err = cli:parse(arg)
+if not args and err then
+	print(string.format('%s: %s', cli.name, err))
+	os.exit(1)
+end
+
 -- load config
-local config = require(arg[1])
+local config = require(args["CONFIG"])
 config.port = config.port or 1195
 
 local tun = nil
 
-if arg[2] ~= "notun" then
+if not args["notun"] then
 	local status, tun_fd, tun_dev = pcall(tun_create)
 	if status then
 		local tun_pipe, tun_pid = tun_fork(tun_dev, config.netmask, config.on_connected)

From e22a8b94dbb0da1b73d87a92aaccaf1b0fd22b6d Mon Sep 17 00:00:00 2001
From: Christian Muehlhaeuser <muesli@gmail.com>
Date: Wed, 21 Feb 2018 08:04:57 +0100
Subject: [PATCH 2/2] Handle invalid config module parameter a bit more
 gracefully

---
 frivpn_client.lua | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/frivpn_client.lua b/frivpn_client.lua
index d6f843b..5822be9 100755
--- a/frivpn_client.lua
+++ b/frivpn_client.lua
@@ -66,6 +66,14 @@ local syscalls = {
 
 }
 
+function prequire(...)
+    local status, lib = pcall(require, ...)
+        if status then
+            return lib
+        end
+    return nil
+end
+
 function lookup_ip(host)
 	local res = posix.getaddrinfo(host, 1195)
 	return res[1].addr
@@ -494,9 +502,13 @@ if not args and err then
 end
 
 -- load config
-local config = require(args["CONFIG"])
-config.port = config.port or 1195
+local config = prequire(args["CONFIG"])
+if not config then
+        print(string.format("Could not load config module %s", arg[1]))
+        os.exit(1)
+end
 
+config.port = config.port or 1195
 local tun = nil
 
 if not args["notun"] then