Uploaded Test files

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Batuhan Berk Başoğlu 2020-11-12 11:05:57 -05:00
parent f584ad9d97
commit 2e81cb7d99
16627 changed files with 2065359 additions and 102444 deletions

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# defusedxml
#
# Copyright (c) 2013 by Christian Heimes <christian@python.org>
# Licensed to PSF under a Contributor Agreement.
# See https://www.python.org/psf/license for licensing details.
"""Defused xml.etree.ElementTree facade
"""
from __future__ import print_function, absolute_import
import sys
import warnings
from xml.etree.ElementTree import TreeBuilder as _TreeBuilder
from xml.etree.ElementTree import parse as _parse
from xml.etree.ElementTree import tostring
from .common import PY3
if PY3:
import importlib
else:
from xml.etree.ElementTree import XMLParser as _XMLParser
from xml.etree.ElementTree import iterparse as _iterparse
from xml.etree.ElementTree import ParseError
from .common import (
DTDForbidden,
EntitiesForbidden,
ExternalReferenceForbidden,
_generate_etree_functions,
)
__origin__ = "xml.etree.ElementTree"
def _get_py3_cls():
"""Python 3.3 hides the pure Python code but defusedxml requires it.
The code is based on test.support.import_fresh_module().
"""
pymodname = "xml.etree.ElementTree"
cmodname = "_elementtree"
pymod = sys.modules.pop(pymodname, None)
cmod = sys.modules.pop(cmodname, None)
sys.modules[cmodname] = None
pure_pymod = importlib.import_module(pymodname)
if cmod is not None:
sys.modules[cmodname] = cmod
else:
sys.modules.pop(cmodname)
sys.modules[pymodname] = pymod
_XMLParser = pure_pymod.XMLParser
_iterparse = pure_pymod.iterparse
ParseError = pure_pymod.ParseError
return _XMLParser, _iterparse, ParseError
if PY3:
_XMLParser, _iterparse, ParseError = _get_py3_cls()
_sentinel = object()
class DefusedXMLParser(_XMLParser):
def __init__(
self,
html=_sentinel,
target=None,
encoding=None,
forbid_dtd=False,
forbid_entities=True,
forbid_external=True,
):
# Python 2.x old style class
_XMLParser.__init__(self, target=target, encoding=encoding)
if html is not _sentinel:
# the 'html' argument has been deprecated and ignored in all
# supported versions of Python. Python 3.8 finally removed it.
if html:
raise TypeError("'html=True' is no longer supported.")
else:
warnings.warn(
"'html' keyword argument is no longer supported. Pass "
"in arguments as keyword arguments.",
category=DeprecationWarning,
)
self.forbid_dtd = forbid_dtd
self.forbid_entities = forbid_entities
self.forbid_external = forbid_external
if PY3:
parser = self.parser
else:
parser = self._parser
if self.forbid_dtd:
parser.StartDoctypeDeclHandler = self.defused_start_doctype_decl
if self.forbid_entities:
parser.EntityDeclHandler = self.defused_entity_decl
parser.UnparsedEntityDeclHandler = self.defused_unparsed_entity_decl
if self.forbid_external:
parser.ExternalEntityRefHandler = self.defused_external_entity_ref_handler
def defused_start_doctype_decl(self, name, sysid, pubid, has_internal_subset):
raise DTDForbidden(name, sysid, pubid)
def defused_entity_decl(
self, name, is_parameter_entity, value, base, sysid, pubid, notation_name
):
raise EntitiesForbidden(name, value, base, sysid, pubid, notation_name)
def defused_unparsed_entity_decl(self, name, base, sysid, pubid, notation_name):
# expat 1.2
raise EntitiesForbidden(name, None, base, sysid, pubid, notation_name) # pragma: no cover
def defused_external_entity_ref_handler(self, context, base, sysid, pubid):
raise ExternalReferenceForbidden(context, base, sysid, pubid)
# aliases
# XMLParse is a typo, keep it for backwards compatibility
XMLTreeBuilder = XMLParse = XMLParser = DefusedXMLParser
parse, iterparse, fromstring = _generate_etree_functions(
DefusedXMLParser, _TreeBuilder, _parse, _iterparse
)
XML = fromstring
__all__ = [
"ParseError",
"XML",
"XMLParse",
"XMLParser",
"XMLTreeBuilder",
"fromstring",
"iterparse",
"parse",
"tostring",
]

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# defusedxml
#
# Copyright (c) 2013 by Christian Heimes <christian@python.org>
# Licensed to PSF under a Contributor Agreement.
# See https://www.python.org/psf/license for licensing details.
"""Defuse XML bomb denial of service vulnerabilities
"""
from __future__ import print_function, absolute_import
from .common import (
DefusedXmlException,
DTDForbidden,
EntitiesForbidden,
ExternalReferenceForbidden,
NotSupportedError,
_apply_defusing,
)
def defuse_stdlib():
"""Monkey patch and defuse all stdlib packages
:warning: The monkey patch is an EXPERIMETNAL feature.
"""
defused = {}
from . import cElementTree
from . import ElementTree
from . import minidom
from . import pulldom
from . import sax
from . import expatbuilder
from . import expatreader
from . import xmlrpc
xmlrpc.monkey_patch()
defused[xmlrpc] = None
for defused_mod in [
cElementTree,
ElementTree,
minidom,
pulldom,
sax,
expatbuilder,
expatreader,
]:
stdlib_mod = _apply_defusing(defused_mod)
defused[defused_mod] = stdlib_mod
return defused
__version__ = "0.6.0"
__all__ = [
"DefusedXmlException",
"DTDForbidden",
"EntitiesForbidden",
"ExternalReferenceForbidden",
"NotSupportedError",
]

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# defusedxml
#
# Copyright (c) 2013 by Christian Heimes <christian@python.org>
# Licensed to PSF under a Contributor Agreement.
# See https://www.python.org/psf/license for licensing details.
"""Defused xml.etree.cElementTree
"""
from __future__ import absolute_import
from xml.etree.cElementTree import TreeBuilder as _TreeBuilder
from xml.etree.cElementTree import parse as _parse
from xml.etree.cElementTree import tostring
# iterparse from ElementTree!
from xml.etree.ElementTree import iterparse as _iterparse
from .ElementTree import DefusedXMLParser
from .common import _generate_etree_functions
__origin__ = "xml.etree.cElementTree"
# XMLParse is a typo, keep it for backwards compatibility
XMLTreeBuilder = XMLParse = XMLParser = DefusedXMLParser
parse, iterparse, fromstring = _generate_etree_functions(
DefusedXMLParser, _TreeBuilder, _parse, _iterparse
)
XML = fromstring
__all__ = [
"XML",
"XMLParse",
"XMLParser",
"XMLTreeBuilder",
"fromstring",
"iterparse",
"parse",
"tostring",
]

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# defusedxml
#
# Copyright (c) 2013 by Christian Heimes <christian@python.org>
# Licensed to PSF under a Contributor Agreement.
# See https://www.python.org/psf/license for licensing details.
"""Common constants, exceptions and helpe functions
"""
import sys
import xml.parsers.expat
PY3 = sys.version_info[0] == 3
# Fail early when pyexpat is not installed correctly
if not hasattr(xml.parsers.expat, "ParserCreate"):
raise ImportError("pyexpat") # pragma: no cover
class DefusedXmlException(ValueError):
"""Base exception
"""
def __repr__(self):
return str(self)
class DTDForbidden(DefusedXmlException):
"""Document type definition is forbidden
"""
def __init__(self, name, sysid, pubid):
super(DTDForbidden, self).__init__()
self.name = name
self.sysid = sysid
self.pubid = pubid
def __str__(self):
tpl = "DTDForbidden(name='{}', system_id={!r}, public_id={!r})"
return tpl.format(self.name, self.sysid, self.pubid)
class EntitiesForbidden(DefusedXmlException):
"""Entity definition is forbidden
"""
def __init__(self, name, value, base, sysid, pubid, notation_name):
super(EntitiesForbidden, self).__init__()
self.name = name
self.value = value
self.base = base
self.sysid = sysid
self.pubid = pubid
self.notation_name = notation_name
def __str__(self):
tpl = "EntitiesForbidden(name='{}', system_id={!r}, public_id={!r})"
return tpl.format(self.name, self.sysid, self.pubid)
class ExternalReferenceForbidden(DefusedXmlException):
"""Resolving an external reference is forbidden
"""
def __init__(self, context, base, sysid, pubid):
super(ExternalReferenceForbidden, self).__init__()
self.context = context
self.base = base
self.sysid = sysid
self.pubid = pubid
def __str__(self):
tpl = "ExternalReferenceForbidden(system_id='{}', public_id={})"
return tpl.format(self.sysid, self.pubid)
class NotSupportedError(DefusedXmlException):
"""The operation is not supported
"""
def _apply_defusing(defused_mod):
assert defused_mod is sys.modules[defused_mod.__name__]
stdlib_name = defused_mod.__origin__
__import__(stdlib_name, {}, {}, ["*"])
stdlib_mod = sys.modules[stdlib_name]
stdlib_names = set(dir(stdlib_mod))
for name, obj in vars(defused_mod).items():
if name.startswith("_") or name not in stdlib_names:
continue
setattr(stdlib_mod, name, obj)
return stdlib_mod
def _generate_etree_functions(DefusedXMLParser, _TreeBuilder, _parse, _iterparse):
"""Factory for functions needed by etree, dependent on whether
cElementTree or ElementTree is used."""
def parse(source, parser=None, forbid_dtd=False, forbid_entities=True, forbid_external=True):
if parser is None:
parser = DefusedXMLParser(
target=_TreeBuilder(),
forbid_dtd=forbid_dtd,
forbid_entities=forbid_entities,
forbid_external=forbid_external,
)
return _parse(source, parser)
def iterparse(
source,
events=None,
parser=None,
forbid_dtd=False,
forbid_entities=True,
forbid_external=True,
):
if parser is None:
parser = DefusedXMLParser(
target=_TreeBuilder(),
forbid_dtd=forbid_dtd,
forbid_entities=forbid_entities,
forbid_external=forbid_external,
)
return _iterparse(source, events, parser)
def fromstring(text, forbid_dtd=False, forbid_entities=True, forbid_external=True):
parser = DefusedXMLParser(
target=_TreeBuilder(),
forbid_dtd=forbid_dtd,
forbid_entities=forbid_entities,
forbid_external=forbid_external,
)
parser.feed(text)
return parser.close()
return parse, iterparse, fromstring

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# defusedxml
#
# Copyright (c) 2013 by Christian Heimes <christian@python.org>
# Licensed to PSF under a Contributor Agreement.
# See https://www.python.org/psf/license for licensing details.
"""Defused xml.dom.expatbuilder
"""
from __future__ import print_function, absolute_import
from xml.dom.expatbuilder import ExpatBuilder as _ExpatBuilder
from xml.dom.expatbuilder import Namespaces as _Namespaces
from .common import DTDForbidden, EntitiesForbidden, ExternalReferenceForbidden
__origin__ = "xml.dom.expatbuilder"
class DefusedExpatBuilder(_ExpatBuilder):
"""Defused document builder"""
def __init__(
self, options=None, forbid_dtd=False, forbid_entities=True, forbid_external=True
):
_ExpatBuilder.__init__(self, options)
self.forbid_dtd = forbid_dtd
self.forbid_entities = forbid_entities
self.forbid_external = forbid_external
def defused_start_doctype_decl(self, name, sysid, pubid, has_internal_subset):
raise DTDForbidden(name, sysid, pubid)
def defused_entity_decl(
self, name, is_parameter_entity, value, base, sysid, pubid, notation_name
):
raise EntitiesForbidden(name, value, base, sysid, pubid, notation_name)
def defused_unparsed_entity_decl(self, name, base, sysid, pubid, notation_name):
# expat 1.2
raise EntitiesForbidden(name, None, base, sysid, pubid, notation_name) # pragma: no cover
def defused_external_entity_ref_handler(self, context, base, sysid, pubid):
raise ExternalReferenceForbidden(context, base, sysid, pubid)
def install(self, parser):
_ExpatBuilder.install(self, parser)
if self.forbid_dtd:
parser.StartDoctypeDeclHandler = self.defused_start_doctype_decl
if self.forbid_entities:
# if self._options.entities:
parser.EntityDeclHandler = self.defused_entity_decl
parser.UnparsedEntityDeclHandler = self.defused_unparsed_entity_decl
if self.forbid_external:
parser.ExternalEntityRefHandler = self.defused_external_entity_ref_handler
class DefusedExpatBuilderNS(_Namespaces, DefusedExpatBuilder):
"""Defused document builder that supports namespaces."""
def install(self, parser):
DefusedExpatBuilder.install(self, parser)
if self._options.namespace_declarations:
parser.StartNamespaceDeclHandler = self.start_namespace_decl_handler
def reset(self):
DefusedExpatBuilder.reset(self)
self._initNamespaces()
def parse(file, namespaces=True, forbid_dtd=False, forbid_entities=True, forbid_external=True):
"""Parse a document, returning the resulting Document node.
'file' may be either a file name or an open file object.
"""
if namespaces:
build_builder = DefusedExpatBuilderNS
else:
build_builder = DefusedExpatBuilder
builder = build_builder(
forbid_dtd=forbid_dtd, forbid_entities=forbid_entities, forbid_external=forbid_external
)
if isinstance(file, str):
fp = open(file, "rb")
try:
result = builder.parseFile(fp)
finally:
fp.close()
else:
result = builder.parseFile(file)
return result
def parseString(
string, namespaces=True, forbid_dtd=False, forbid_entities=True, forbid_external=True
):
"""Parse a document from a string, returning the resulting
Document node.
"""
if namespaces:
build_builder = DefusedExpatBuilderNS
else:
build_builder = DefusedExpatBuilder
builder = build_builder(
forbid_dtd=forbid_dtd, forbid_entities=forbid_entities, forbid_external=forbid_external
)
return builder.parseString(string)

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# defusedxml
#
# Copyright (c) 2013 by Christian Heimes <christian@python.org>
# Licensed to PSF under a Contributor Agreement.
# See https://www.python.org/psf/license for licensing details.
"""Defused xml.sax.expatreader
"""
from __future__ import print_function, absolute_import
from xml.sax.expatreader import ExpatParser as _ExpatParser
from .common import DTDForbidden, EntitiesForbidden, ExternalReferenceForbidden
__origin__ = "xml.sax.expatreader"
class DefusedExpatParser(_ExpatParser):
"""Defused SAX driver for the pyexpat C module."""
def __init__(
self,
namespaceHandling=0,
bufsize=2 ** 16 - 20,
forbid_dtd=False,
forbid_entities=True,
forbid_external=True,
):
_ExpatParser.__init__(self, namespaceHandling, bufsize)
self.forbid_dtd = forbid_dtd
self.forbid_entities = forbid_entities
self.forbid_external = forbid_external
def defused_start_doctype_decl(self, name, sysid, pubid, has_internal_subset):
raise DTDForbidden(name, sysid, pubid)
def defused_entity_decl(
self, name, is_parameter_entity, value, base, sysid, pubid, notation_name
):
raise EntitiesForbidden(name, value, base, sysid, pubid, notation_name)
def defused_unparsed_entity_decl(self, name, base, sysid, pubid, notation_name):
# expat 1.2
raise EntitiesForbidden(name, None, base, sysid, pubid, notation_name) # pragma: no cover
def defused_external_entity_ref_handler(self, context, base, sysid, pubid):
raise ExternalReferenceForbidden(context, base, sysid, pubid)
def reset(self):
_ExpatParser.reset(self)
parser = self._parser
if self.forbid_dtd:
parser.StartDoctypeDeclHandler = self.defused_start_doctype_decl
if self.forbid_entities:
parser.EntityDeclHandler = self.defused_entity_decl
parser.UnparsedEntityDeclHandler = self.defused_unparsed_entity_decl
if self.forbid_external:
parser.ExternalEntityRefHandler = self.defused_external_entity_ref_handler
def create_parser(*args, **kwargs):
return DefusedExpatParser(*args, **kwargs)

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# defusedxml
#
# Copyright (c) 2013 by Christian Heimes <christian@python.org>
# Licensed to PSF under a Contributor Agreement.
# See https://www.python.org/psf/license for licensing details.
"""DEPRECATED Example code for lxml.etree protection
The code has NO protection against decompression bombs.
"""
from __future__ import print_function, absolute_import
import threading
import warnings
from lxml import etree as _etree
from .common import DTDForbidden, EntitiesForbidden, NotSupportedError
LXML3 = _etree.LXML_VERSION[0] >= 3
__origin__ = "lxml.etree"
tostring = _etree.tostring
warnings.warn(
"defusedxml.lxml is no longer supported and will be removed in a " "future release.",
category=DeprecationWarning,
stacklevel=2,
)
class RestrictedElement(_etree.ElementBase):
"""A restricted Element class that filters out instances of some classes
"""
__slots__ = ()
# blacklist = (etree._Entity, etree._ProcessingInstruction, etree._Comment)
blacklist = _etree._Entity
def _filter(self, iterator):
blacklist = self.blacklist
for child in iterator:
if isinstance(child, blacklist):
continue
yield child
def __iter__(self):
iterator = super(RestrictedElement, self).__iter__()
return self._filter(iterator)
def iterchildren(self, tag=None, reversed=False):
iterator = super(RestrictedElement, self).iterchildren(tag=tag, reversed=reversed)
return self._filter(iterator)
def iter(self, tag=None, *tags):
iterator = super(RestrictedElement, self).iter(tag=tag, *tags)
return self._filter(iterator)
def iterdescendants(self, tag=None, *tags):
iterator = super(RestrictedElement, self).iterdescendants(tag=tag, *tags)
return self._filter(iterator)
def itersiblings(self, tag=None, preceding=False):
iterator = super(RestrictedElement, self).itersiblings(tag=tag, preceding=preceding)
return self._filter(iterator)
def getchildren(self):
iterator = super(RestrictedElement, self).__iter__()
return list(self._filter(iterator))
def getiterator(self, tag=None):
iterator = super(RestrictedElement, self).getiterator(tag)
return self._filter(iterator)
class GlobalParserTLS(threading.local):
"""Thread local context for custom parser instances
"""
parser_config = {
"resolve_entities": False,
# 'remove_comments': True,
# 'remove_pis': True,
}
element_class = RestrictedElement
def createDefaultParser(self):
parser = _etree.XMLParser(**self.parser_config)
element_class = self.element_class
if self.element_class is not None:
lookup = _etree.ElementDefaultClassLookup(element=element_class)
parser.set_element_class_lookup(lookup)
return parser
def setDefaultParser(self, parser):
self._default_parser = parser
def getDefaultParser(self):
parser = getattr(self, "_default_parser", None)
if parser is None:
parser = self.createDefaultParser()
self.setDefaultParser(parser)
return parser
_parser_tls = GlobalParserTLS()
getDefaultParser = _parser_tls.getDefaultParser
def check_docinfo(elementtree, forbid_dtd=False, forbid_entities=True):
"""Check docinfo of an element tree for DTD and entity declarations
The check for entity declarations needs lxml 3 or newer. lxml 2.x does
not support dtd.iterentities().
"""
docinfo = elementtree.docinfo
if docinfo.doctype:
if forbid_dtd:
raise DTDForbidden(docinfo.doctype, docinfo.system_url, docinfo.public_id)
if forbid_entities and not LXML3:
# lxml < 3 has no iterentities()
raise NotSupportedError("Unable to check for entity declarations " "in lxml 2.x")
if forbid_entities:
for dtd in docinfo.internalDTD, docinfo.externalDTD:
if dtd is None:
continue
for entity in dtd.iterentities():
raise EntitiesForbidden(entity.name, entity.content, None, None, None, None)
def parse(source, parser=None, base_url=None, forbid_dtd=False, forbid_entities=True):
if parser is None:
parser = getDefaultParser()
elementtree = _etree.parse(source, parser, base_url=base_url)
check_docinfo(elementtree, forbid_dtd, forbid_entities)
return elementtree
def fromstring(text, parser=None, base_url=None, forbid_dtd=False, forbid_entities=True):
if parser is None:
parser = getDefaultParser()
rootelement = _etree.fromstring(text, parser, base_url=base_url)
elementtree = rootelement.getroottree()
check_docinfo(elementtree, forbid_dtd, forbid_entities)
return rootelement
XML = fromstring
def iterparse(*args, **kwargs):
raise NotSupportedError("defused lxml.etree.iterparse not available")

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# defusedxml
#
# Copyright (c) 2013 by Christian Heimes <christian@python.org>
# Licensed to PSF under a Contributor Agreement.
# See https://www.python.org/psf/license for licensing details.
"""Defused xml.dom.minidom
"""
from __future__ import print_function, absolute_import
from xml.dom.minidom import _do_pulldom_parse
from . import expatbuilder as _expatbuilder
from . import pulldom as _pulldom
__origin__ = "xml.dom.minidom"
def parse(
file, parser=None, bufsize=None, forbid_dtd=False, forbid_entities=True, forbid_external=True
):
"""Parse a file into a DOM by filename or file object."""
if parser is None and not bufsize:
return _expatbuilder.parse(
file,
forbid_dtd=forbid_dtd,
forbid_entities=forbid_entities,
forbid_external=forbid_external,
)
else:
return _do_pulldom_parse(
_pulldom.parse,
(file,),
{
"parser": parser,
"bufsize": bufsize,
"forbid_dtd": forbid_dtd,
"forbid_entities": forbid_entities,
"forbid_external": forbid_external,
},
)
def parseString(
string, parser=None, forbid_dtd=False, forbid_entities=True, forbid_external=True
):
"""Parse a file into a DOM from a string."""
if parser is None:
return _expatbuilder.parseString(
string,
forbid_dtd=forbid_dtd,
forbid_entities=forbid_entities,
forbid_external=forbid_external,
)
else:
return _do_pulldom_parse(
_pulldom.parseString,
(string,),
{
"parser": parser,
"forbid_dtd": forbid_dtd,
"forbid_entities": forbid_entities,
"forbid_external": forbid_external,
},
)

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# defusedxml
#
# Copyright (c) 2013 by Christian Heimes <christian@python.org>
# Licensed to PSF under a Contributor Agreement.
# See https://www.python.org/psf/license for licensing details.
"""Defused xml.dom.pulldom
"""
from __future__ import print_function, absolute_import
from xml.dom.pulldom import parse as _parse
from xml.dom.pulldom import parseString as _parseString
from .sax import make_parser
__origin__ = "xml.dom.pulldom"
def parse(
stream_or_string,
parser=None,
bufsize=None,
forbid_dtd=False,
forbid_entities=True,
forbid_external=True,
):
if parser is None:
parser = make_parser()
parser.forbid_dtd = forbid_dtd
parser.forbid_entities = forbid_entities
parser.forbid_external = forbid_external
return _parse(stream_or_string, parser, bufsize)
def parseString(
string, parser=None, forbid_dtd=False, forbid_entities=True, forbid_external=True
):
if parser is None:
parser = make_parser()
parser.forbid_dtd = forbid_dtd
parser.forbid_entities = forbid_entities
parser.forbid_external = forbid_external
return _parseString(string, parser)

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# defusedxml
#
# Copyright (c) 2013 by Christian Heimes <christian@python.org>
# Licensed to PSF under a Contributor Agreement.
# See https://www.python.org/psf/license for licensing details.
"""Defused xml.sax
"""
from __future__ import print_function, absolute_import
from xml.sax import InputSource as _InputSource
from xml.sax import ErrorHandler as _ErrorHandler
from . import expatreader
__origin__ = "xml.sax"
def parse(
source,
handler,
errorHandler=_ErrorHandler(),
forbid_dtd=False,
forbid_entities=True,
forbid_external=True,
):
parser = make_parser()
parser.setContentHandler(handler)
parser.setErrorHandler(errorHandler)
parser.forbid_dtd = forbid_dtd
parser.forbid_entities = forbid_entities
parser.forbid_external = forbid_external
parser.parse(source)
def parseString(
string,
handler,
errorHandler=_ErrorHandler(),
forbid_dtd=False,
forbid_entities=True,
forbid_external=True,
):
from io import BytesIO
if errorHandler is None:
errorHandler = _ErrorHandler()
parser = make_parser()
parser.setContentHandler(handler)
parser.setErrorHandler(errorHandler)
parser.forbid_dtd = forbid_dtd
parser.forbid_entities = forbid_entities
parser.forbid_external = forbid_external
inpsrc = _InputSource()
inpsrc.setByteStream(BytesIO(string))
parser.parse(inpsrc)
def make_parser(parser_list=[]):
return expatreader.create_parser()

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# defusedxml
#
# Copyright (c) 2013 by Christian Heimes <christian@python.org>
# Licensed to PSF under a Contributor Agreement.
# See https://www.python.org/psf/license for licensing details.
"""Defused xmlrpclib
Also defuses gzip bomb
"""
from __future__ import print_function, absolute_import
import io
from .common import DTDForbidden, EntitiesForbidden, ExternalReferenceForbidden, PY3
if PY3:
__origin__ = "xmlrpc.client"
from xmlrpc.client import ExpatParser
from xmlrpc import client as xmlrpc_client
from xmlrpc import server as xmlrpc_server
from xmlrpc.client import gzip_decode as _orig_gzip_decode
from xmlrpc.client import GzipDecodedResponse as _OrigGzipDecodedResponse
else:
__origin__ = "xmlrpclib"
from xmlrpclib import ExpatParser
import xmlrpclib as xmlrpc_client
xmlrpc_server = None
from xmlrpclib import gzip_decode as _orig_gzip_decode
from xmlrpclib import GzipDecodedResponse as _OrigGzipDecodedResponse
try:
import gzip
except ImportError: # pragma: no cover
gzip = None
# Limit maximum request size to prevent resource exhaustion DoS
# Also used to limit maximum amount of gzip decoded data in order to prevent
# decompression bombs
# A value of -1 or smaller disables the limit
MAX_DATA = 30 * 1024 * 1024 # 30 MB
def defused_gzip_decode(data, limit=None):
"""gzip encoded data -> unencoded data
Decode data using the gzip content encoding as described in RFC 1952
"""
if not gzip: # pragma: no cover
raise NotImplementedError
if limit is None:
limit = MAX_DATA
f = io.BytesIO(data)
gzf = gzip.GzipFile(mode="rb", fileobj=f)
try:
if limit < 0: # no limit
decoded = gzf.read()
else:
decoded = gzf.read(limit + 1)
except IOError: # pragma: no cover
raise ValueError("invalid data")
f.close()
gzf.close()
if limit >= 0 and len(decoded) > limit:
raise ValueError("max gzipped payload length exceeded")
return decoded
class DefusedGzipDecodedResponse(gzip.GzipFile if gzip else object):
"""a file-like object to decode a response encoded with the gzip
method, as described in RFC 1952.
"""
def __init__(self, response, limit=None):
# response doesn't support tell() and read(), required by
# GzipFile
if not gzip: # pragma: no cover
raise NotImplementedError
self.limit = limit = limit if limit is not None else MAX_DATA
if limit < 0: # no limit
data = response.read()
self.readlength = None
else:
data = response.read(limit + 1)
self.readlength = 0
if limit >= 0 and len(data) > limit:
raise ValueError("max payload length exceeded")
self.stringio = io.BytesIO(data)
gzip.GzipFile.__init__(self, mode="rb", fileobj=self.stringio)
def read(self, n):
if self.limit >= 0:
left = self.limit - self.readlength
n = min(n, left + 1)
data = gzip.GzipFile.read(self, n)
self.readlength += len(data)
if self.readlength > self.limit:
raise ValueError("max payload length exceeded")
return data
else:
return gzip.GzipFile.read(self, n)
def close(self):
gzip.GzipFile.close(self)
self.stringio.close()
class DefusedExpatParser(ExpatParser):
def __init__(self, target, forbid_dtd=False, forbid_entities=True, forbid_external=True):
ExpatParser.__init__(self, target)
self.forbid_dtd = forbid_dtd
self.forbid_entities = forbid_entities
self.forbid_external = forbid_external
parser = self._parser
if self.forbid_dtd:
parser.StartDoctypeDeclHandler = self.defused_start_doctype_decl
if self.forbid_entities:
parser.EntityDeclHandler = self.defused_entity_decl
parser.UnparsedEntityDeclHandler = self.defused_unparsed_entity_decl
if self.forbid_external:
parser.ExternalEntityRefHandler = self.defused_external_entity_ref_handler
def defused_start_doctype_decl(self, name, sysid, pubid, has_internal_subset):
raise DTDForbidden(name, sysid, pubid)
def defused_entity_decl(
self, name, is_parameter_entity, value, base, sysid, pubid, notation_name
):
raise EntitiesForbidden(name, value, base, sysid, pubid, notation_name)
def defused_unparsed_entity_decl(self, name, base, sysid, pubid, notation_name):
# expat 1.2
raise EntitiesForbidden(name, None, base, sysid, pubid, notation_name) # pragma: no cover
def defused_external_entity_ref_handler(self, context, base, sysid, pubid):
raise ExternalReferenceForbidden(context, base, sysid, pubid)
def monkey_patch():
xmlrpc_client.FastParser = DefusedExpatParser
xmlrpc_client.GzipDecodedResponse = DefusedGzipDecodedResponse
xmlrpc_client.gzip_decode = defused_gzip_decode
if xmlrpc_server:
xmlrpc_server.gzip_decode = defused_gzip_decode
def unmonkey_patch():
xmlrpc_client.FastParser = None
xmlrpc_client.GzipDecodedResponse = _OrigGzipDecodedResponse
xmlrpc_client.gzip_decode = _orig_gzip_decode
if xmlrpc_server:
xmlrpc_server.gzip_decode = _orig_gzip_decode