codekingpro/portable-devtools

1# defusedxml2#3# Copyright (c) 2013 by Christian Heimes <christian@python.org>4# Licensed to PSF under a Contributor Agreement.5# See https://www.python.org/psf/license for licensing details.6"""Defused xml.dom.expatbuilder7"""8from __future__ import print_function, absolute_import9 10from xml.dom.expatbuilder import ExpatBuilder as _ExpatBuilder11from xml.dom.expatbuilder import Namespaces as _Namespaces12 13from .common import DTDForbidden, EntitiesForbidden, ExternalReferenceForbidden14 15__origin__ = "xml.dom.expatbuilder"16 17 18class DefusedExpatBuilder(_ExpatBuilder):19    """Defused document builder"""20 21    def __init__(22        self, options=None, forbid_dtd=False, forbid_entities=True, forbid_external=True23    ):24        _ExpatBuilder.__init__(self, options)25        self.forbid_dtd = forbid_dtd26        self.forbid_entities = forbid_entities27        self.forbid_external = forbid_external28 29    def defused_start_doctype_decl(self, name, sysid, pubid, has_internal_subset):30        raise DTDForbidden(name, sysid, pubid)31 32    def defused_entity_decl(33        self, name, is_parameter_entity, value, base, sysid, pubid, notation_name34    ):35        raise EntitiesForbidden(name, value, base, sysid, pubid, notation_name)36 37    def defused_unparsed_entity_decl(self, name, base, sysid, pubid, notation_name):38        # expat 1.239        raise EntitiesForbidden(name, None, base, sysid, pubid, notation_name)  # pragma: no cover40 41    def defused_external_entity_ref_handler(self, context, base, sysid, pubid):42        raise ExternalReferenceForbidden(context, base, sysid, pubid)43 44    def install(self, parser):45        _ExpatBuilder.install(self, parser)46 47        if self.forbid_dtd:48            parser.StartDoctypeDeclHandler = self.defused_start_doctype_decl49        if self.forbid_entities:50            # if self._options.entities:51            parser.EntityDeclHandler = self.defused_entity_decl52            parser.UnparsedEntityDeclHandler = self.defused_unparsed_entity_decl53        if self.forbid_external:54            parser.ExternalEntityRefHandler = self.defused_external_entity_ref_handler55 56 57class DefusedExpatBuilderNS(_Namespaces, DefusedExpatBuilder):58    """Defused document builder that supports namespaces."""59 60    def install(self, parser):61        DefusedExpatBuilder.install(self, parser)62        if self._options.namespace_declarations:63            parser.StartNamespaceDeclHandler = self.start_namespace_decl_handler64 65    def reset(self):66        DefusedExpatBuilder.reset(self)67        self._initNamespaces()68 69 70def parse(file, namespaces=True, forbid_dtd=False, forbid_entities=True, forbid_external=True):71    """Parse a document, returning the resulting Document node.72 73    'file' may be either a file name or an open file object.74    """75    if namespaces:76        build_builder = DefusedExpatBuilderNS77    else:78        build_builder = DefusedExpatBuilder79    builder = build_builder(80        forbid_dtd=forbid_dtd, forbid_entities=forbid_entities, forbid_external=forbid_external81    )82 83    if isinstance(file, str):84        fp = open(file, "rb")85        try:86            result = builder.parseFile(fp)87        finally:88            fp.close()89    else:90        result = builder.parseFile(file)91    return result92 93 94def parseString(95    string, namespaces=True, forbid_dtd=False, forbid_entities=True, forbid_external=True96):97    """Parse a document from a string, returning the resulting98    Document node.99    """100    if namespaces:101        build_builder = DefusedExpatBuilderNS102    else:103        build_builder = DefusedExpatBuilder104    builder = build_builder(105        forbid_dtd=forbid_dtd, forbid_entities=forbid_entities, forbid_external=forbid_external106    )107    return builder.parseString(string)108