Esempio n. 1
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 def FormatAsHexStringTest(self):
   self.assertEqual(utils.FormatAsHexString(10), "0x1b")
   self.assertEqual(utils.FormatAsHexString(10, 4), "0x001b")
   self.assertEqual(utils.FormatAsHexString(10, 16), "0x000000000000001b")
   # No trailing "L".
   self.assertEqual(utils.FormatAsHexString(int(1e19)), "0x8ac7230489e80000")
   self.assertEqual(
       utils.FormatAsHexString(int(1e19), 5), "0x8ac7230489e80000")
Esempio n. 2
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class RekallResponseConverter(ExportConverter):
    """Export converter for RekallResponse objects."""

    input_rdf_type = "RekallResponse"

    OUTPUT_CLASSES = {}

    OBJECT_RENDERERS = {
        "_EPROCESS": RekallEProcessRenderer,
        "Address": lambda x: utils.FormatAsHexString(x["value"]),
        "AddressSpace": lambda x: x["name"],
        "BaseObject": lambda x: "@%s" % utils.FormatAsHexString(x["offset"]),
        "Enumeration": lambda x: "%s (%s)" % (x["enum"], x["value"]),
        "Instruction": lambda x: utils.SmartStr(x["value"]),
        "Literal": lambda x: utils.SmartStr(x["value"]),
        "NativeType": lambda x: utils.SmartStr(x["value"]),
        "NoneObject": lambda x: "-",
        "Pointer": lambda x: utils.FormatAsHexString(x["target"], 14),
        "PaddedAddress": lambda x: utils.FormatAsHexString(x["value"], 14),
        "str": RekallStringRenderer,
        "Struct": lambda x: utils.FormatAsHexString(x["offset"]),
        "UnixTimeStamp": lambda x: utils.FormatAsTimestamp(x["epoch"])
    }

    def _RenderObject(self, obj):
        """Renders a single object - i.e. a table cell."""

        if not hasattr(obj, "iteritems"):
            # Maybe we have to deal with legacy strings, ecnoded as lists with first
            # element being "+" for base64 strings and "*" for unicode strings -
            # check it.
            if isinstance(obj,
                          list) and len(obj) == 2 and obj[0] in ["*", "+"]:
                return utils.SmartStr(obj[1])

            return utils.SmartStr(obj)

        if "string_value" in obj:
            return obj["string_value"]

        if "mro" in obj:
            obj_mro = obj["mro"]
            if isinstance(obj_mro, basestring):
                obj_mro = obj_mro.split(":")

            for mro_type in obj_mro:
                if mro_type in self.OBJECT_RENDERERS:
                    return self.OBJECT_RENDERERS[mro_type](obj)

        return utils.SmartStr(obj)

    def _GenerateOutputClass(self, class_name, tables):
        """Generates output class with a given name for a given set of tables."""

        output_class = type(utils.SmartStr(class_name),
                            (rdfvalue.RDFProtoStruct, ), {})

        if not tables:
            raise RuntimeError(
                "Can't generate output class without Rekall table "
                "definition.")

        field_number = 1
        output_class.AddDescriptor(
            structs.ProtoEmbedded(name="metadata",
                                  field_number=field_number,
                                  nested=rdfvalue.ExportedMetadata))

        field_number += 1
        output_class.AddDescriptor(
            structs.ProtoString(name="section_name",
                                field_number=field_number))

        field_number += 1
        output_class.AddDescriptor(
            structs.ProtoString(name="text", field_number=field_number))

        # All the tables are merged into one. This is done so that if plugin
        # outputs multiple tables, we get all possible columns in the output
        # RDFValue.
        used_names = set()
        for table in tables:
            for column_header in table:
                column_name = None
                try:
                    column_name = column_header["cname"]
                except KeyError:
                    pass

                if not column_name:
                    column_name = column_header["name"]

                if not column_name:
                    raise RuntimeError(
                        "Can't determine column name in table header.")

                if column_name in used_names:
                    continue

                field_number += 1
                used_names.add(column_name)
                output_class.AddDescriptor(
                    structs.ProtoString(name=column_name,
                                        field_number=field_number))

        return output_class

    def _GetOutputClass(self, plugin_name, tables):
        output_class_name = "RekallExport_" + plugin_name

        try:
            return RekallResponseConverter.OUTPUT_CLASSES[output_class_name]
        except KeyError:
            output_class = self._GenerateOutputClass(output_class_name, tables)
            RekallResponseConverter.OUTPUT_CLASSES[
                output_class_name] = output_class
            return output_class

    def _HandleTableRow(self, metadata, context_dict, message, output_class):
        """Handles a single row in one of the tables in RekallResponse."""
        attrs = {}
        for key, value in message[1].iteritems():
            if hasattr(output_class, key):
                # ProtoString expects a unicode object, so let's convert
                # everything to unicode strings.
                attrs[key] = utils.SmartUnicode(self._RenderObject(value))

        result = output_class(**attrs)
        result.metadata = metadata

        try:
            result.section_name = self._RenderObject(context_dict["s"]["name"])
        except KeyError:
            pass

        return result

    def Convert(self, metadata, rekall_response, token=None):
        """Convert a single RekallResponse."""
        if rekall_response.HasField("json_context_messages"):
            parsed_context_messages = json.loads(
                rekall_response.json_context_messages)
        else:
            parsed_context_messages = []

        context_dict = dict(parsed_context_messages)
        if "t" in context_dict:
            tables = [context_dict["t"]]
        else:
            tables = []

        parsed_messages = json.loads(rekall_response.json_messages)

        # First scan all the messages and find all table definitions there.
        for message in parsed_messages:
            # We do not decode lexicon-based responses. If there's non empty
            # lexicon in the message, we ignore the whole response altogether.
            if message[0] == "l" and message[1]:
                logging.warn("Non-empty lexicon found. Client %s is too old.",
                             rekall_response.client_urn)
                break

            if message[0] == "t":
                tables.append(message[1])

        # Generate output class based on all table definitions.
        output_class = self._GetOutputClass(rekall_response.plugin, tables)

        # Fill generated output class instances with values from every row.
        for message in parsed_messages:
            if message[0] in ["s", "t"]:
                context_dict[message[0]] = message[1]

            if message[0] == "r":
                yield self._HandleTableRow(metadata, context_dict, message,
                                           output_class)

    def BatchConvert(self, metadata_value_pairs, token=None):
        """Convert batch of RekallResponses."""

        for metadata, rekall_response in metadata_value_pairs:
            for result in self.Convert(metadata, rekall_response):
                yield result
Esempio n. 3
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class RekallResponseConverter(ExportConverter):
    """Export converter for RekallResponse objects."""

    input_rdf_type = "RekallResponse"

    OUTPUT_CLASSES = {}

    OBJECT_RENDERERS = {
        "Address": lambda x: utils.FormatAsHexString(x["value"]),
        "Pointer": lambda x: utils.FormatAsHexString(x["target"], 14),
        "PaddedAddress": lambda x: utils.FormatAsHexString(x["value"], 14),
        "AddressSpace": lambda x: x["name"],
        "Enumeration": lambda x: "%s (%s)" % (x["enum"], x["value"]),
        "Literal": lambda x: utils.SmartStr(x["value"]),
        "NativeType": lambda x: utils.SmartStr(x["value"]),
        "NoneObject": lambda x: "-",
        "BaseObject": lambda x: "@%s" % utils.FormatAsHexString(x["offset"]),
        "Struct": lambda x: utils.FormatAsHexString(x["offset"]),
        "UnixTimeStamp": lambda x: utils.FormatAsTimestamp(x["epoch"]),
        "_EPROCESS": lambda x: "%s (%s)" %
        (x["Cybox"]["Name"], x["Cybox"]["PID"])
    }

    def _RenderObject(self, obj):
        """Renders a single object - i.e. a table cell."""

        if not hasattr(obj, "iteritems"):
            return utils.SmartStr(obj)

        if "string_value" in obj:
            return obj["string_value"]

        if "mro" in obj:
            for mro_type in obj["mro"]:
                if mro_type in self.OBJECT_RENDERERS:
                    return self.OBJECT_RENDERERS[mro_type](obj)

        return utils.SmartStr(obj)

    def _ParseJsonMessages(self, messages):
        """Parses json messages using Rekall DataExportRenderer."""

        json_data = json.loads(messages)
        for message in json_data:
            if len(message) >= 1:
                object_renderer = json_renderer.JsonObjectRenderer(
                    renderer="DataExportRenderer")
                try:
                    message = [
                        object_renderer.DecodeFromJsonSafe(s, {})
                        for s in message
                    ]
                except AttributeError as e:
                    # Old clients may still return lexicon-encoded data, just ignore them.
                    if "has no attribute 'lexicon'" in str(e):
                        continue
                    else:
                        raise

            yield message

    def _GenerateOutputClass(self, class_name, context_dict):
        """Generates output class with a given name for a given context."""

        output_class = type(utils.SmartStr(class_name),
                            (rdfvalue.RDFProtoStruct, ), {})

        if "t" not in context_dict:
            raise RuntimeError(
                "Can't generate output class without Rekall table "
                "definition.")

        field_number = 1
        output_class.AddDescriptor(
            structs.ProtoEmbedded(name="metadata",
                                  field_number=field_number,
                                  nested=rdfvalue.ExportedMetadata))

        field_number += 1
        output_class.AddDescriptor(
            structs.ProtoString(name="section_name",
                                field_number=field_number))

        field_number += 1
        output_class.AddDescriptor(
            structs.ProtoString(name="text", field_number=field_number))

        for column_header in context_dict["t"]:
            field_number += 1

            column_name = None
            try:
                column_name = column_header["cname"]
            except KeyError:
                pass

            if not column_name:
                column_name = column_header["name"]

            if not column_name:
                raise RuntimeError(
                    "Can't determine column name in table header.")

            output_class.AddDescriptor(
                structs.ProtoString(name=column_name,
                                    field_number=field_number))

        return output_class

    def _GetOutputClass(self, plugin_name, context_dict):
        output_class_name = "RekallExport_" + plugin_name

        try:
            return RekallResponseConverter.OUTPUT_CLASSES[output_class_name]
        except KeyError:
            output_class = self._GenerateOutputClass(output_class_name,
                                                     context_dict)
            RekallResponseConverter.OUTPUT_CLASSES[
                output_class_name] = output_class
            return output_class

    def _HandleTableRow(self, metadata, plugin_name, context_dict, message):
        """Handles a single row in one of the tables in RekallResponse."""

        output_class = self._GetOutputClass(plugin_name, context_dict)
        attrs = {}
        for key, value in message[1].iteritems():
            if hasattr(output_class, key):
                attrs[key] = self._RenderObject(value)

        result = output_class(**attrs)
        result.metadata = metadata

        try:
            result.section_name = context_dict["s"]["name"]
        except KeyError:
            pass

        return result

    def Convert(self, metadata, rekall_response, token=None):
        """Convert a single RekallResponse."""
        if rekall_response.HasField("json_context_messages"):
            parsed_context_messages = list(
                self._ParseJsonMessages(rekall_response.json_context_messages))
        else:
            parsed_context_messages = []

        context_dict = dict(parsed_context_messages)

        for message in self._ParseJsonMessages(rekall_response.json_messages):
            if message[0] in ["s", "t"]:
                context_dict[message[0]] = message[1]

            if message[0] == "r":
                yield self._HandleTableRow(metadata, rekall_response.plugin,
                                           context_dict, message)

    def BatchConvert(self, metadata_value_pairs, token=None):
        """Convert batch of RekallResponses."""

        for metadata, rekall_response in metadata_value_pairs:
            for result in self.Convert(metadata, rekall_response):
                yield result