#!/usr/bin/env python
# -*- coding: utf-8 -*-

import socket
import struct
import time
from hashlib import md5
import sys
import os
import random
import traceback

# CONFIG
server = "192.168.100.150"
username = ""
password = ""
host_name = "LIYUANYUAN"
host_os = "DrCOM"
host_ip = "10.30.22.17"
PRIMARY_DNS = "114.114.114.114"
dhcp_server = "0.0.0.0"
mac = 0xb888e3051680
CONTROLCHECKSTATUS = '\x20'
ADAPTERNUM = '\x01'
KEEP_ALIVE_VERSION = '\xdc\x02'
'''
AUTH_VERSION:
    unsigned char ClientVerInfoAndInternetMode;
    unsigned char DogVersion;
'''
AUTH_VERSION = '\x0a\x00'
IPDOG = '\x01'
ror_version = False
# CONFIG_END

nic_name = '' #Indicate your nic, e.g. 'eth0.2'.nic_name
bind_ip = '0.0.0.0'

class ChallengeException (Exception):
    def __init__(self):
        pass

class LoginException (Exception):
    def __init__(self):
        pass

def bind_nic():
    try:
        import fcntl
        def get_ip_address(ifname):
            s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
            return socket.inet_ntoa(fcntl.ioctl(
                s.fileno(),
                0x8915,  # SIOCGIFADDR
                struct.pack('256s', ifname[:15])
            )[20:24])
        return get_ip_address(nic_name)
    except ImportError as e:
        print('Indicate nic feature need to be run under Unix based system.')
        return '0.0.0.0'
    except IOError as e:
        print(nic_name + 'is unacceptable !')
        return '0.0.0.0'
    finally:
        return '0.0.0.0'

if nic_name != '':
    bind_ip = bind_nic()

s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
# s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
s.bind((bind_ip, 61440))

s.settimeout(3)
SALT = ''
IS_TEST = True
# specified fields based on version
CONF = "/etc/drcom.conf"
UNLIMITED_RETRY = True
EXCEPTION = False
DEBUG = False #log saves to file
LOG_PATH = '/var/log/drcom_client.log'
if IS_TEST:
    DEBUG = True
    LOG_PATH = 'drcom_client.log'


def log(*args, **kwargs):
    s = ' '.join(args)
    print s
    if DEBUG:
        with open(LOG_PATH,'a') as f:
            f.write(s + '\n')

def challenge(svr,ran):
    while True:
        t = struct.pack("<H", int(ran)%(0xFFFF))
        s.sendto("\x01\x04"+t+"\x2d"+"\x00"*15, (svr, 61440))
        try:
            data, address = s.recvfrom(1024)
            log('[challenge] recv',data.encode('hex'))
        except:
            log('[challenge] timeout, retrying...')
            continue

        if address == (svr, 61440):
            break
        else:
            continue
    log('[DEBUG] challenge:\n' + data.encode('hex'))
    if data[0] != '\x02':
        raise ChallengeException
    log('[challenge] challenge packet sent.')
    return data[4:8]

def md5sum(s):
    m = md5()
    m.update(s)
    return m.digest()

def dump(n):
    s = '%x' % n
    if len(s) & 1:
        s = '0' + s
    return s.decode('hex')

def ror(md5, pwd):
    ret = ''
    for i in range(len(pwd)):
        x = ord(md5[i]) ^ ord(pwd[i])
        ret += chr(((x<<3)&0xFF) + (x>>5))
    return ret

def keep_alive_package_builder(number,random,tail,type=1,first=False):
    data = '\x07'+ chr(number) + '\x28\x00\x0b' + chr(type)
    if first :
        data += '\x0f\x27'
    else:
        data += KEEP_ALIVE_VERSION
    data += '\x3c\x69' + '\x00' * 6
    data += tail
    data += '\x00' * 4
    #data += struct.pack("!H",0xdc02)
    if type == 3:
        foo = ''.join([chr(int(i)) for i in host_ip.split('.')]) # host_ip
        #CRC
        # edited on 2014/5/12, filled zeros to checksum
        # crc = packet_CRC(data+foo)
        crc = '\x00' * 4
        #data += struct.pack("!I",crc) + foo + '\x00' * 8
        data += crc + foo + '\x00' * 8
    else: #packet type = 1
        data += '\x00' * 16
    return data

# def packet_CRC(s):
#     ret = 0
#     for i in re.findall('..', s):
#         ret ^= struct.unpack('>h', i)[0]
#         ret &= 0xFFFF
#     ret = ret * 0x2c7
#     return ret

def keep_alive2(*args):
    #first keep_alive:
    #number = number (mod 7)
    #status = 1: first packet user sended
    #         2: first packet user recieved
    #         3: 2nd packet user sended
    #         4: 2nd packet user recieved
    #   Codes for test
    tail = ''
    packet = ''
    svr = server
    ran = random.randint(0,0xFFFF)
    ran += random.randint(1,10)
    # 2014/10/15 add by latyas, maybe svr sends back a file packet
    svr_num = 0
    packet = keep_alive_package_builder(svr_num,dump(ran),'\x00'*4,1,True)
    while True:
        log('[keep-alive2] send1',packet.encode('hex'))
        s.sendto(packet, (svr, 61440))
        data, address = s.recvfrom(1024)
        log('[keep-alive2] recv1',data.encode('hex'))
        if data.startswith('\x07\x00\x28\x00') or data.startswith('\x07' + chr(svr_num)  + '\x28\x00'):
            break
        elif data[0] == '\x07' and data[2] == '\x10':
            log('[keep-alive2] recv file, resending..')
            svr_num = svr_num + 1
            # packet = keep_alive_package_builder(svr_num,dump(ran),'\x00'*4,1, False)
            break
        else:
            log('[keep-alive2] recv1/unexpected',data.encode('hex'))
    #log('[keep-alive2] recv1',data.encode('hex'))

    ran += random.randint(1,10)
    packet = keep_alive_package_builder(svr_num, dump(ran),'\x00'*4,1,False)
    log('[keep-alive2] send2',packet.encode('hex'))
    s.sendto(packet, (svr, 61440))
    while True:
        data, address = s.recvfrom(1024)
        if data[0] == '\x07':
            svr_num = svr_num + 1
            break
        else:
            log('[keep-alive2] recv2/unexpected',data.encode('hex'))
    log('[keep-alive2] recv2',data.encode('hex'))
    tail = data[16:20]


    ran += random.randint(1,10)
    packet = keep_alive_package_builder(svr_num,dump(ran),tail,3,False)
    log('[keep-alive2] send3',packet.encode('hex'))
    s.sendto(packet, (svr, 61440))
    while True:
        data, address = s.recvfrom(1024)
        if data[0] == '\x07':
            svr_num = svr_num + 1
            break
        else:
            log('[keep-alive2] recv3/unexpected',data.encode('hex'))
    log('[keep-alive2] recv3',data.encode('hex'))
    tail = data[16:20]
    log("[keep-alive2] keep-alive2 loop was in daemon.")

    i = svr_num
    while True:
        try:
            time.sleep(20)
            keep_alive1(*args)
            ran += random.randint(1,10)
            packet = keep_alive_package_builder(i,dump(ran),tail,1,False)
            #log('DEBUG: keep_alive2,packet 4\n',packet.encode('hex'))
            log('[keep_alive2] send',str(i),packet.encode('hex'))
            s.sendto(packet, (svr, 61440))
            data, address = s.recvfrom(1024)
            log('[keep_alive2] recv',data.encode('hex'))
            tail = data[16:20]
            #log('DEBUG: keep_alive2,packet 4 return\n',data.encode('hex'))

            ran += random.randint(1,10)
            packet = keep_alive_package_builder(i+1,dump(ran),tail,3,False)
            #log('DEBUG: keep_alive2,packet 5\n',packet.encode('hex'))
            s.sendto(packet, (svr, 61440))
            log('[keep_alive2] send',str(i+1),packet.encode('hex'))
            data, address = s.recvfrom(1024)
            log('[keep_alive2] recv',data.encode('hex'))
            tail = data[16:20]
            #log('DEBUG: keep_alive2,packet 5 return\n',data.encode('hex'))
            i = (i+2) % 0xFF
        except:
            log('[keep_alive2] error', 'raise Exception to main()')
            raise

def checksum(s):
    ret = 1234
    x = 0
    for i in [x*4 for x in range(0, -(-len(s)//4))]:
        ret ^= int(s[i:i+4].ljust(4, '\x00')[::-1].encode('hex'), 16)
    ret = (1968 * ret) & 0xffffffff
    return struct.pack('<I', ret)

def mkpkt(salt, usr, pwd, mac):
    '''
	struct  _tagLoginPacket
	{
	    struct _tagDrCOMHeader Header;
	    unsigned char PasswordMd5[MD5_LEN];
	    char Account[ACCOUNT_MAX_LEN];
	    unsigned char ControlCheckStatus;
	    unsigned char AdapterNum;
	    unsigned char MacAddrXORPasswordMD5[MAC_LEN];
	    unsigned char PasswordMd5_2[MD5_LEN];
	    unsigned char HostIpNum;
	    unsigned int HostIPList[HOST_MAX_IP_NUM];
	    unsigned char HalfMD5[8];
	    unsigned char DogFlag;
	    unsigned int unkown2;
	    struct _tagHostInfo HostInfo;
	    unsigned char ClientVerInfoAndInternetMode;
	    unsigned char DogVersion;
	};
    '''
    data = '\x03\x01\x00' + chr(len(usr) + 20)
    data += md5sum('\x03\x01' + salt + pwd)
    data += usr.ljust(36, '\x00')
    data += CONTROLCHECKSTATUS
    data += ADAPTERNUM
    data += dump(int(data[4:10].encode('hex'),16)^mac).rjust(6, '\x00') #mac xor md51
    data += md5sum("\x01" + pwd + salt + '\x00' * 4) #md52
    data += '\x01' # number of ip
    data += ''.join([chr(int(i)) for i in host_ip.split('.')]) #x.x.x.x ->
    data += '\00' * 4 #your ipaddress 2
    data += '\00' * 4 #your ipaddress 3
    data += '\00' * 4 #your ipaddress 4
    data += md5sum(data + '\x14\x00\x07\x0B')[:8] #md53
    data += IPDOG
    data += '\x00'*4 # unknown2
    '''
	struct  _tagOSVERSIONINFO
	{
	    unsigned int OSVersionInfoSize;
	    unsigned int MajorVersion;
	    unsigned int MinorVersion;
	    unsigned int BuildNumber;
	    unsigned int PlatformID;
	    char ServicePack[128];
	};
	struct  _tagHostInfo
	{
	    char HostName[HOST_NAME_MAX_LEN];
	    unsigned int DNSIP1;
	    unsigned int DHCPServerIP;
	    unsigned int DNSIP2;
	    unsigned int WINSIP1;
	    unsigned int WINSIP2;
	    struct _tagDrCOM_OSVERSIONINFO OSVersion;
	};
    '''
    data += host_name.ljust(32, '\x00') # _tagHostInfo.HostName
    data += ''.join([chr(int(i)) for i in PRIMARY_DNS.split('.')]) # _tagHostInfo.DNSIP1
    data += ''.join([chr(int(i)) for i in dhcp_server.split('.')]) # _tagHostInfo.DHCPServerIP
    data += '\x00\x00\x00\x00' # _tagHostInfo.DNSIP2
    data += '\x00' * 4 # _tagHostInfo.WINSIP1
    data += '\x00' * 4 # _tagHostInfo.WINSIP2
    data += '\x94\x00\x00\x00' # _tagHostInfo.OSVersion.OSVersionInfoSize
    data += '\x05\x00\x00\x00' # _tagHostInfo.OSVersion.MajorVersion
    data += '\x01\x00\x00\x00' # _tagHostInfo.OSVersion.MinorVersion
    data += '\x28\x0A\x00\x00' # _tagHostInfo.OSVersion.BuildNumber
    data += '\x02\x00\x00\x00' # _tagHostInfo.OSVersion.PlatformID
    # _tagHostInfo.OSVersion.ServicePack
    #data += host_os.ljust(32, '\x00')
    data += '\x44\x72\x43\x4f\x4d\x00\x83\x00'
    #data += '\x00' * 96
    # END OF _tagHostInfo

    data += AUTH_VERSION
    if ror_version:
        '''
	struct  _tagLDAPAuth
	{
	    unsigned char Code;
	    unsigned char PasswordLen;
	    unsigned char Password[MD5_LEN];
	};
        '''
        data += '\x00' # _tagLDAPAuth.Code
        data += chr(len(pwd)) # _tagLDAPAuth.PasswordLen
        data += ror(md5sum('\x03\x01' + salt + pwd), pwd) # _tagLDAPAuth.Password
    '''
	struct  _tagDrcomAuthExtData
	{
	    unsigned char Code;
	    unsigned char Len;
	    unsigned long CRC;
	    unsigned short Option;
	    unsigned char AdapterAddress[MAC_LEN];
	};
    '''
    data += '\x02' # _tagDrcomAuthExtData.Code
    data += '\x0C' # _tagDrcomAuthExtData.Len
    data += checksum(data + '\x01\x26\x07\x11\x00\x00' + dump(mac)) # _tagDrcomAuthExtData.CRC
    data += '\x00\x00' # _tagDrcomAuthExtData.Option
    data += dump(mac) # _tagDrcomAuthExtData.AdapterAddress
    # END OF _tagDrcomAuthExtData
    if ror_version:
        data += '\x00' * (8 - len(pwd))
        if len(pwd)%2:
            data += '\x00'
    else:
        data += '\x00' # auto logout / default: False
        data += '\x00' # broadcast mode / default : False
    data += '\xE9\x13' #unknown, filled numbers randomly =w=

    log('[mkpkt]',data.encode('hex'))
    return data

def login(usr, pwd, svr):
    global SALT
    global AUTH_INFO

    i = 0
    timeoutcount = 0
    while True:
        salt = challenge(svr,time.time()+random.randint(0xF,0xFF))
        SALT = salt
        packet = mkpkt(salt, usr, pwd, mac)
        log('[login] send',packet.encode('hex'))
        s.sendto(packet, (svr, 61440))
        log('[login] packet sent.')
        try:
            data, address = s.recvfrom(1024)
            log('[login] recv',data.encode('hex'))
            if address == (svr, 61440) :
                if data[0] == '\x04':
                    log('[login] loged in')
                    AUTH_INFO = data[23:39]
                    break
                else:
                    log('[login] login failed.')
                    if IS_TEST:
                        time.sleep(3)
                    else:
                        time.sleep(30)
                    continue
            else:
                if i >= 5 and UNLIMITED_RETRY == False :
                    log('[login] exception occured.')
                    sys.exit(1)
                else:
                    i += 1
                    continue
        except socket.timeout as e:
            print(e)
            log('[login] recv timeout.')
            timeoutcount += 1
            if timeoutcount >= 5:
                log('[login] recv timeout exception occured 5 times.')
                sys.exit(1)
            else:
                continue

    log('[login] login sent')
    #0.8 changed:
    return data[23:39]
    #return data[-22:-6]

def logout(usr, pwd, svr, mac, auth_info):
    salt = challenge(svr, time.time()+random.randint(0xF, 0xFF))
    if salt:
        data = '\x06\x01\x00' + chr(len(usr) + 20)
        data += md5sum('\x03\x01' + salt + pwd)
        data += usr.ljust(36, '\x00')
        data += CONTROLCHECKSTATUS
        data += ADAPTERNUM
        data += dump(int(data[4:10].encode('hex'),16)^mac).rjust(6, '\x00')
        # data += '\x44\x72\x63\x6F' # Drco
        data += auth_info
        s.send(data)
        data, address = s.recvfrom(1024)
        if data[:1] == '\x04':
            log('[logout_auth] logouted.')

def keep_alive1(salt,tail,pwd,svr):
    foo = struct.pack('!H',int(time.time())%0xFFFF)
    data = '\xff' + md5sum('\x03\x01'+salt+pwd) + '\x00\x00\x00'
    data += tail
    data += foo + '\x00\x00\x00\x00'
    log('[keep_alive1] send',data.encode('hex'))

    s.sendto(data, (svr, 61440))
    while True:
        try:
            data, address = s.recvfrom(1024)
            if data[0] == '\x07':
                break
            else:
                log('[keep-alive1]recv/not expected',data.encode('hex'))
        except:
            log('[keep_alive1] error', 'raise Exception to main() or keep_alive2()')
            raise
    log('[keep-alive1] recv',data.encode('hex'))

def empty_socket_buffer():
#empty buffer for some fucking schools
    log('starting to empty socket buffer')
    try:
        while True:
            data, address = s.recvfrom(1024)
            log('recived sth unexpected',data.encode('hex'))
            if s == '':
                break
    except:
        # get exception means it has done.
        log('exception in empty_socket_buffer')
        pass
    log('emptyed')
def daemon():
    with open('/var/run/jludrcom.pid','w') as f:
        f.write(str(os.getpid()))

def main():
    if not IS_TEST:
        daemon()
        execfile(CONF, globals())
    log("auth svr: " + server + "\nusername: " + username + "\npassword: " + password + "\nmac: " + str(hex(mac))[:-1])
    log("bind ip: " + bind_ip)
    while True:
        try:
            package_tail = login(username, password, server)
        except LoginException:
            continue
        log('package_tail',package_tail.encode('hex'))
        #keep_alive1 is fucking bullshit!
        empty_socket_buffer()
        try:
            keep_alive1(SALT,package_tail,password,server)
            keep_alive2(SALT,package_tail,password,server)
        except Exception as e:
            print(e)
            log('[main] error', 'something was wrong in keep_alives, do everything again')
            log(traceback.format_exc())
            time.sleep(3)
            #empty socket buffer before relogin
            empty_socket_buffer()
            continue

if __name__ == "__main__":
    main()