#!/usr/bin/python3
#
#Copyright (c) 2006 Olivier Sessink
#All rights reserved.
#
#Redistribution and use in source and binary forms, with or without
#modification, are permitted provided that the following conditions 
#are met:
#  * Redistributions of source code must retain the above copyright 
#	notice, this list of conditions and the following disclaimer.
#  * Redistributions in binary form must reproduce the above 
#	copyright notice, this list of conditions and the following 
#	disclaimer in the documentation and/or other materials provided 
#	with the distribution.
#  * The names of its contributors may not be used to endorse or 
#	promote products derived from this software without specific 
#	prior written permission.
#
#THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
#"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
#LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 
#FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 
#COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 
#INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 
#BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 
#LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 
#CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 
#LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 
#ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
#POSSIBILITY OF SUCH DAMAGE.
#

from __future__ import print_function

import os
import getopt
import sys
import pwd
import string

users = {}

def getpwuid_cached(uid):
	if uid in users:
		return users[uid]
	else:
		user = pwd.getpwuid(uid)
		users[uid] = user
		return user

class ListResult:
	pid = None
	jail = None
	exe = None
	uid = None
	username = None
	cmdline = None
	
	
	def __init__(self, pid):
		self.pid = pid
		sb = os.stat('/proc/'+pid)
		self.uid = sb.st_uid
		pwdret = getpwuid_cached(sb.st_uid)
		self.username = pwdret[0]
		self.jail = os.readlink('/proc/'+pid+'/root')
		self.exe = os.readlink('/proc/'+pid+'/exe')
		fd = open('/proc/'+pid+'/cmdline')
		buf = fd.read(4096)
		self.cmdline = ' '.join(buf.split('\0')[1:])
		fd.close()
	
	def __cmp__(self, other):
		ret = cmp(self.jail, other.jail)
		if(ret ==0):
			ret = cmp(self.uid, other.uid)
			if(ret ==0):
				ret = cmp(self.pid, other.pid)
		return ret	 

	def optistr(self,usernamelen,jaillen,cmdlen):
		formatstring = '%%-06s %%-0%ds %%-0%ds %%-0%ds' % (usernamelen,jaillen,cmdlen)
		return formatstring % (self.pid, self.username[:usernamelen], self.jail[:jaillen], (self.exe+' '+self.cmdline)[:cmdlen])

	def __str__(self):
		return '%-06s %-05s %-011s %-019s %-019s' % (self.pid, self.username, self.jail, self.exe,self.cmdline)

def printResults(results,wide):
	if (len(results)==0):
		print('No jailed processes found')
		return
	results.sort()
	usernamelen=4 # User
	jaillen=4 # Jail
	cmdlen=7 #Command
	for result in results:
		usernamelen = max(usernamelen,len(result.username))
		jaillen = max(jaillen,len(result.jail))
		cmdlen = max(cmdlen,len(result.cmdline+' '+result.exe))

	if (not wide):
		cmdlen = min(cmdlen,80-5-usernamelen-jaillen-4)
	
	titleformat =  '%%-06s %%-0%ds %%-0%ds %%-0%ds' % (usernamelen,jaillen,min(cmdlen,80-5-usernamelen-jaillen-4))
	print(titleformat % ('Pid', 'User','Jail','Command'))
	for result in results:
		if (wide):
			mycmdlen = len(result.cmdline+' '+result.exe)
		else:
			mycmdlen = cmdlen
		print(result.optistr(usernamelen,jaillen,mycmdlen))


def runList(verbose,jail):
	# open /proc/
	results = []
	dirlist = os.listdir('/proc')
	try:
		for entry in dirlist:
			if (entry.isdigit()):
				# we have a process, now read the link root
					ret = os.readlink('/proc/'+entry+'/root')
					if (ret != '/'):
						results.append(ListResult(entry))
	except OSError as e:
		if (e.errno == 13):
			print('Permission denied')
	return results

def printusage():
	print("jk_list, lists pocesses running in a chroot jail")
	print("-h --help		print this message")
	print("-j --jail=/path  list only processes in this jail")
	print("-w --wide   print wide listing")

def main():
	try:
		opts, args = getopt.getopt(sys.argv[1:], "hwj:", ['wide', "help", "jail"])
	except getopt.GetoptError:
		printusage()
		sys.exit(1)
	verbose = 0
	jail = None
	wide = 0
	for o, a in opts:
		if o in ("-h", "--help"):
			printusage()
			sys.exit()
		if o in ("-j", "--jail"):
			jail = a
		if o in ("-v", "--verbose"):
			verbose = 1
		if o in ("-w", "--wide"):
			wide = 1
	results = runList(verbose,jail)
	printResults(results,wide)

if __name__ == "__main__":
	main()