Synnefo » snf-vncauthproxy

#

#

# Copyright (c) 2010 GRNET SA

#

# 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.

#

# 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.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA

# 02110-1301, USA.

import d3des

from struct import pack, unpack

RFB_AUTH_SUCCESS = 0

RFB_AUTH_ERROR = 1

RFB_AUTHTYPE_VNC = 2

RFB_AUTHTYPE_NONE = 1

RFB_AUTHTYPE_ERROR = 0

RFB_SUPPORTED_AUTHTYPES = [RFB_AUTHTYPE_NONE, RFB_AUTHTYPE_VNC]

RFB_VERSION_3_8 = "RFB 003.008"

RFB_VERSION_3_7 = "RFB 003.007"

RFB_VERSION_3_3 = "RFB 003.003"

RFB_VALID_VERSIONS = [

    RFB_VERSION_3_3,

#    RFB_VERSION_3_7,

    RFB_VERSION_3_8,

]

class RfbError(Exception):

    pass

def check_version(version):

    if version.strip()[:11] in RFB_VALID_VERSIONS:

        return version.strip()[:11]

    else:

        return None

def make_auth_request(*args, **kwargs):

    auth_methods = args

    version = kwargs['version']

    if version == RFB_VERSION_3_3:

        if len(auth_methods) != 1:

            raise RfbError("Only single authentication type may be specified for RFB 3.3")

    auth_methods = set(auth_methods)

    for method in auth_methods:

        if method not in RFB_SUPPORTED_AUTHTYPES:

            raise RfbError("Unsupported authentication type: %d" % method)

    if version == RFB_VERSION_3_3:

        return pack('>I', *auth_methods)

    else:

        return pack('B' + 'B' * len(auth_methods), len(auth_methods), *auth_methods)

def parse_auth_request(request):

    length = unpack('B', request[0])[0]

    if length == 0:

        return []

    return unpack('B' * length, request[1:])

def parse_client_authtype(authtype):

    return unpack('B', authtype[0])[0]

def from_u32(val):

    return unpack('>L', val)[0]

def to_u32(val):

    return pack('>L', val)

def from_u8(val):

    return unpack('B', val)[0]

def to_u8(val):

    return pack('B', val)

def check_password(challenge, response, password):

    return d3des.generate_response((password + '\0' * 8 )[:8],

                                   challenge) == response