#!/usr/libexec/platform-python
# -*- mode: python; -*-
#
# Copyright (C) 2012 - 2013 Paul Wouters <pwouters@redhat.com>
#
# Based on old perl and shell code:
# Copyright (C) 2003 Sam Sgro <sam@freeswan.org>
# Copyright (C) 2005-2008 Michael Richardson <mcr@xelerance.com>
# Copyright (C) 2005-2009 Paul Wouters <paul@xelerance.com>
# Copyright (C) 2012-2014 Paul Wouters <paul@libreswan.org>
#
# Based on "verify" from the FreeS/WAN distribution, (C) 2001 Michael
# Richardson <mcr@freeswan.org>
#
# This program is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by the
# Free Software Foundation; either version 2 of the License, or (at your
# option) any later version.  See <https://www.gnu.org/licenses/gpl2.txt>.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
# or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
# for more details.

import os, sys, subprocess, glob, socket, locale
from shutil import which

retcode = 0

conffile = "/etc/ipsec.conf"
confdir = "/etc"
ipsecbin = "/usr/sbin/ipsec"
iptables = "true"
nftables = "false"

prefencoding = locale.getpreferredencoding(False)

if not os.path.isfile(ipsecbin):
	# hopefully somewhere in our path then
	ipsecbin = "ipsec"

if not os.path.isfile(conffile):
	if not os.path.isfile("%s/ipsec.conf"%confdir):
		# try some fall backs
		if os.path.isfile("/etc/ipsec.conf"):
			print("WARNING: ipsec.conf not found at compiled-in location '%s/ipsec.conf', using /etc/ipsec.conf instead" %confdir)
			confdir = "/etc/"
		elif os.path.isfile("/usr/local/etc/ipsec.conf"):
			print("WARNING: ipsec.conf not found at compiled-in location '%s/ipsec.conf', using /etc/ipsec.conf instead"%confdir)
			confdir = "/usr/local/etc/"
		else:
			sys.exit("Failed to find ipsec.conf - checked %s, /etc and /usr/local/etc"%confdir)

# Should we print in colour by default?
colour = 0
try:
	p = subprocess.Popen("consoletype", stdout=subprocess.PIPE, stderr=subprocess.PIPE)
	output, err = p.communicate()
	output = output.decode(prefencoding).strip()
	if output in ("vc","tty","pty"):
		colour = 1
except:
	try:
		p = subprocess.Popen("tput colors", stdout=subprocess.PIPE, stderr=subprocess.PIPE)
		output, err = p.communicate()
		if int(output) > 0:
			colour = 1
	except:
		pass


def printfun(text):
	# suppress newline
	sys.stdout.write("%-50s"%text)

def print_result(rcode, rtext):
	global colour
	global retcode
	OK = '\033[92m'
	WARN = '\033[93m'
	FAIL = '\033[91m'
	ENDC = '\033[0m'

	if rcode == "FAIL":
		retcode += 1
		if not rtext:
			rtext = "FAILED"
		if colour:
			print("\t[%s%s%s]"%(FAIL,rtext,ENDC))
		else:
			print("\t[%s]"%rtext)
	elif rcode == "WARN":
		if not rtext:
			rtext = "WARNING"
		if colour:
			print("\t[%s%s%s]"%(WARN,rtext,ENDC))
		else:
			print("\t[%s]"%rtext)
	elif rcode == "OK":
		if not rtext:
			rtext = "OK"
		if colour:
			print("\t[%s%s%s]"%(OK,rtext,ENDC))
		else:
			print("\t[%s]"%rtext)
	else:
		print("INTERNAL ERROR - unknown rcode:%s"%rcode)


def plutocheck():
	global retcode
	printfun("Checking that pluto is running")
	p = subprocess.Popen(["pidof", "pluto"], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
	output, err = p.communicate()
	if not output:
		retcode += 1
		print_result("FAIL","FAILED")
		return
	else:
		print_result("OK","OK")

	# only if pluto is running, do the listen tests and ipsec  secrets test
	udp500check()
	udp4500check()
	ipsecsecretcheck()

def rpfiltercheck():
	global retcode
	fail = 0
	printfun("Checking rp_filter")
	for dirname in glob.glob("/proc/sys/net/ipv4/conf/*"):
		val = open("%s/rp_filter"%dirname,"r").read().strip()
		if val == "1":
			if fail == 0:
				print_result("FAIL","ENABLED")
			fail = 1
			printfun(" %s/rp_filter"%dirname)
			print_result("FAIL","ENABLED")
			retcode += 1
	if fail == 0:
			print_result("OK","OK")
	else:
		print("  rp_filter is not fully aware of IPsec and should be disabled")

def cmdchecks():
	global retcode
	printfun("Checking 'ip' command")
	if not os.path.isfile("/sbin/ip") and not os.path.isfile("/usr/sbin/ip") \
	   and not os.path.isfile("/bin/ip"):
		print_result("FAIL","FAILED")
		retcode += 1
	p = subprocess.Popen(["ip", "xfrm"], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
	output, err = p.communicate()
	err = err.decode(prefencoding)
	if not "XFRM" in err:
		print_result("FAIL","IP XFRM BROKEN")
		retcode += 1
	else:
		print_result("OK","OK")

	if "true" in iptables:
		printfun("Checking 'iptables' command")

		if which("iptables"):
			print_result("OK","OK")
		else:
			print_result("WARN","MISSING")

	if "true" in nftables:
		printfun("Checking 'nft' command")
		nft = which("nft")
		if nft:
			print_result("OK","OK")
		else:
			print_result("WARN","MISSING")

	printfun("Checking 'prelink' command does not interfere with FIPS")
	if os.path.isfile("/sbin/prelink") or os.path.isfile("/usr/sbin/prelink"):
		if os.path.isfile("/etc/prelink.cache"):
			print_result("WARN","PRESENT")
		else:
			print_result("FAIL","IN USE")
			retcode += 1
	else:
		print_result("OK","OK")

def udp500check():
	global retcode
	printfun(" Pluto listening for IKE on udp 500")
	try:
		p = subprocess.Popen(["ss", "-n", "-a", "-u", "sport = :500"], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
		output, err = p.communicate()
		output = output.decode(prefencoding)
		if ":500" in output:
			print_result("OK","OK")
		else:
			print_result("FAIL","FAILED")
			retcode += 1
	except:
		print_result("FAIL","FAILED")
		retcode += 1

def udp4500check():
	global retcode
	global sscmd
	printfun(" Pluto listening for IKE/NAT-T on udp 4500")
	if not sscmd:
		print_result("WARN","UNKNOWN")
		print("(install the 'ss' command to activate this test)")
		return
	try:
		p = subprocess.Popen([sscmd, "-n", "-a", "-u", "sport = :4500"], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
		output, err = p.communicate()
		output = output.decode(prefencoding)
		if ":4500" in output:
			print_result("OK","OK")
		else:
			print_result("WARN","DISABLED")
	except:
		print_result("FAIL","DISABLED")
		retcode += 1

def installstartcheck():
	global retcode
	print("Verifying installed system and configuration files\n")
	printfun("Version check and ipsec on-path")
	try:
		p = subprocess.Popen(["ipsec", "--version"], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
		output, err = p.communicate()
		output = output.decode(prefencoding)
		if "swan" in output:
			print_result("OK","OK")
			print(output.replace("Linux","").strip())
		else:
			print_result("FAIL","FAILED")
	except:
		print_result("FAIL","FAILED")

	printfun("Checking for IPsec support in kernel")
	if not os.path.isfile("/proc/net/ipsec_eroute") and not os.path.isfile("/proc/sys/net/core/xfrm_acq_expires"):
		print_result("FAIL","FAILED")
		if "no kernel code presently loaded" in output:
			print("\n The ipsec service should be started before running 'ipsec verify'\n")
		return
	else:
		print_result("OK","OK")

	installchecknetkey()

def installchecknetkey():
	global retcode
	print(" NETKEY: Testing XFRM related proc values")
	for option in ( "send_redirects", "accept_redirects"):
		printfun("         ICMP default/%s"%option)
		try:
			redir = open("/proc/sys/net/ipv4/conf/default/%s"%option,"r").read().strip()
		except:
			print_result("FAIL","VERY BROKEN KERNEL")
			return
		if redir == "0":
			print_result("OK","OK")
		else:
			print_result("FAIL","NOT DISABLED")
			print("\n  Disable /proc/sys/net/ipv4/conf/*/%s or XFRM/NETKEY will act on or cause sending of bogus ICMP redirects!\n"%option)

	printfun("         XFRM larval drop")
	try:
		larval = open("/proc/sys/net/core/xfrm_larval_drop","r").read().strip()
	except:
		print_result("FAIL","OLD OR BROKEN KERNEL")
		return
	if larval == "1":
		print_result("OK","OK")
	else:
		print_result("FAIL","NOT ENABLED")

def ipsecsecretcheck():
	global retcode
	# we need to be root, because the only way to check is to reload them
	printfun(" Pluto ipsec.secret syntax")
	uid = os.getuid()
	if uid != 0:
		print_result("WARN","UNKNOWN")
		print(" (run ipsec verify as root to test ipsec.secrets)")
		return

	p = subprocess.Popen(["ipsec","secrets"], universal_newlines=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
	output, err = p.communicate()
	if "ERROR" in output:
		print_result("FAIL","PARSE ERROR")
		for line in output.split("\n"):
			line = line.strip()
			if line and "ERROR" in line:
				print("  %s"%line)
	elif "WARNING" in output:
		print_result("WARN","OBSOLETE")
		for line in output.split("\n"):
			line = line.strip()
			if line and "WARNING" in line:
				print("  %s"%line)
	else:
		print_result("OK","OK")

def ipsecconfcheck():
	global retcode
	printfun("Pluto ipsec.conf syntax")
	p = subprocess.Popen(["ipsec","addconn","--checkconfig"], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
	output, err = p.communicate()
	err = err.decode(prefencoding)
	if "syntax error" in err:
		print_result("FAIL","PARSE ERROR")
		print(err)
	else:
		print_result("OK","OK")

def configsetupcheck():
	global retcode
	p = subprocess.Popen(["ipsec","addconn","--configsetup"], universal_newlines=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
	configsetup, err = p.communicate()

	# grab obsolete settings
	printfun("Checking for obsolete ipsec.conf options")
	if not err:
		print_result("OK","OK")
	else:
		print_result("WARN","OBSOLETE KEYWORD")
		print(err[:-1])

def main():
	global retcode
	global sscmd
	if os.path.isfile("/usr/sbin/ss"):
		sscmd = "/usr/sbin/ss"
	elif os.path.isfile("/bin/ss"):
		sscmd = "/bin/ss"
	elif os.path.isfile("/sbin/ss"):
		sscmd = "/sbin/ss"

	installstartcheck()
	ipsecconfcheck()
	rpfiltercheck()
	plutocheck()
	cmdchecks()
	configsetupcheck()
	if retcode:
		plural = ""
		if retcode > 1:
			plural = "s"
		sys.stderr.write("\nipsec verify: encountered %s error%s - see 'man ipsec_verify' for help\n"%(retcode,plural))
		sys.exit(retcode)

if __name__ == "__main__":
	main()