744 lines
27 KiB
Python
744 lines
27 KiB
Python
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"""
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Multi-part parsing for file uploads.
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Exposes one class, ``MultiPartParser``, which feeds chunks of uploaded data to
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file upload handlers for processing.
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"""
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import base64
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import binascii
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import collections
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import html
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from django.conf import settings
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from django.core.exceptions import (
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RequestDataTooBig,
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SuspiciousMultipartForm,
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TooManyFieldsSent,
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TooManyFilesSent,
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)
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from django.core.files.uploadhandler import SkipFile, StopFutureHandlers, StopUpload
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from django.utils.datastructures import MultiValueDict
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from django.utils.encoding import force_str
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from django.utils.http import parse_header_parameters
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from django.utils.regex_helper import _lazy_re_compile
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__all__ = ("MultiPartParser", "MultiPartParserError", "InputStreamExhausted")
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class MultiPartParserError(Exception):
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pass
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class InputStreamExhausted(Exception):
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"""
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No more reads are allowed from this device.
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"""
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pass
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RAW = "raw"
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FILE = "file"
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FIELD = "field"
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FIELD_TYPES = frozenset([FIELD, RAW])
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class MultiPartParser:
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"""
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An RFC 7578 multipart/form-data parser.
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``MultiValueDict.parse()`` reads the input stream in ``chunk_size`` chunks
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and returns a tuple of ``(MultiValueDict(POST), MultiValueDict(FILES))``.
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"""
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boundary_re = _lazy_re_compile(r"[ -~]{0,200}[!-~]")
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def __init__(self, META, input_data, upload_handlers, encoding=None):
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"""
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Initialize the MultiPartParser object.
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:META:
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The standard ``META`` dictionary in Django request objects.
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:input_data:
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The raw post data, as a file-like object.
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:upload_handlers:
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A list of UploadHandler instances that perform operations on the
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uploaded data.
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:encoding:
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The encoding with which to treat the incoming data.
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"""
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# Content-Type should contain multipart and the boundary information.
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content_type = META.get("CONTENT_TYPE", "")
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if not content_type.startswith("multipart/"):
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raise MultiPartParserError("Invalid Content-Type: %s" % content_type)
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try:
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content_type.encode("ascii")
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except UnicodeEncodeError:
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raise MultiPartParserError(
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"Invalid non-ASCII Content-Type in multipart: %s"
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% force_str(content_type)
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)
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# Parse the header to get the boundary to split the parts.
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_, opts = parse_header_parameters(content_type)
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boundary = opts.get("boundary")
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if not boundary or not self.boundary_re.fullmatch(boundary):
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raise MultiPartParserError(
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"Invalid boundary in multipart: %s" % force_str(boundary)
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)
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# Content-Length should contain the length of the body we are about
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# to receive.
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try:
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content_length = int(META.get("CONTENT_LENGTH", 0))
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except (ValueError, TypeError):
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content_length = 0
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if content_length < 0:
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# This means we shouldn't continue...raise an error.
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raise MultiPartParserError("Invalid content length: %r" % content_length)
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self._boundary = boundary.encode("ascii")
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self._input_data = input_data
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# For compatibility with low-level network APIs (with 32-bit integers),
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# the chunk size should be < 2^31, but still divisible by 4.
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possible_sizes = [x.chunk_size for x in upload_handlers if x.chunk_size]
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self._chunk_size = min([2**31 - 4] + possible_sizes)
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self._meta = META
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self._encoding = encoding or settings.DEFAULT_CHARSET
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self._content_length = content_length
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self._upload_handlers = upload_handlers
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def parse(self):
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# Call the actual parse routine and close all open files in case of
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# errors. This is needed because if exceptions are thrown the
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# MultiPartParser will not be garbage collected immediately and
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# resources would be kept alive. This is only needed for errors because
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# the Request object closes all uploaded files at the end of the
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# request.
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try:
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return self._parse()
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except Exception:
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if hasattr(self, "_files"):
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for _, files in self._files.lists():
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for fileobj in files:
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fileobj.close()
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raise
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def _parse(self):
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"""
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Parse the POST data and break it into a FILES MultiValueDict and a POST
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MultiValueDict.
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Return a tuple containing the POST and FILES dictionary, respectively.
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"""
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from django.http import QueryDict
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encoding = self._encoding
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handlers = self._upload_handlers
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# HTTP spec says that Content-Length >= 0 is valid
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# handling content-length == 0 before continuing
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if self._content_length == 0:
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return QueryDict(encoding=self._encoding), MultiValueDict()
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# See if any of the handlers take care of the parsing.
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# This allows overriding everything if need be.
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for handler in handlers:
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result = handler.handle_raw_input(
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self._input_data,
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self._meta,
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self._content_length,
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self._boundary,
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encoding,
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)
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# Check to see if it was handled
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if result is not None:
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return result[0], result[1]
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# Create the data structures to be used later.
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self._post = QueryDict(mutable=True)
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self._files = MultiValueDict()
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# Instantiate the parser and stream:
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stream = LazyStream(ChunkIter(self._input_data, self._chunk_size))
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# Whether or not to signal a file-completion at the beginning of the loop.
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old_field_name = None
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counters = [0] * len(handlers)
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# Number of bytes that have been read.
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num_bytes_read = 0
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# To count the number of keys in the request.
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num_post_keys = 0
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# To count the number of files in the request.
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num_files = 0
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# To limit the amount of data read from the request.
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read_size = None
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# Whether a file upload is finished.
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uploaded_file = True
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try:
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for item_type, meta_data, field_stream in Parser(stream, self._boundary):
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if old_field_name:
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# We run this at the beginning of the next loop
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# since we cannot be sure a file is complete until
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# we hit the next boundary/part of the multipart content.
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self.handle_file_complete(old_field_name, counters)
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old_field_name = None
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uploaded_file = True
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if (
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item_type in FIELD_TYPES
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and settings.DATA_UPLOAD_MAX_NUMBER_FIELDS is not None
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):
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# Avoid storing more than DATA_UPLOAD_MAX_NUMBER_FIELDS.
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num_post_keys += 1
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# 2 accounts for empty raw fields before and after the
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# last boundary.
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if settings.DATA_UPLOAD_MAX_NUMBER_FIELDS + 2 < num_post_keys:
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raise TooManyFieldsSent(
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"The number of GET/POST parameters exceeded "
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"settings.DATA_UPLOAD_MAX_NUMBER_FIELDS."
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)
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try:
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disposition = meta_data["content-disposition"][1]
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field_name = disposition["name"].strip()
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except (KeyError, IndexError, AttributeError):
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continue
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transfer_encoding = meta_data.get("content-transfer-encoding")
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if transfer_encoding is not None:
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transfer_encoding = transfer_encoding[0].strip()
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field_name = force_str(field_name, encoding, errors="replace")
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if item_type == FIELD:
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# Avoid reading more than DATA_UPLOAD_MAX_MEMORY_SIZE.
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if settings.DATA_UPLOAD_MAX_MEMORY_SIZE is not None:
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read_size = (
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settings.DATA_UPLOAD_MAX_MEMORY_SIZE - num_bytes_read
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)
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# This is a post field, we can just set it in the post
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if transfer_encoding == "base64":
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raw_data = field_stream.read(size=read_size)
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num_bytes_read += len(raw_data)
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try:
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data = base64.b64decode(raw_data)
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except binascii.Error:
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data = raw_data
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else:
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data = field_stream.read(size=read_size)
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num_bytes_read += len(data)
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# Add two here to make the check consistent with the
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# x-www-form-urlencoded check that includes '&='.
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num_bytes_read += len(field_name) + 2
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if (
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settings.DATA_UPLOAD_MAX_MEMORY_SIZE is not None
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and num_bytes_read > settings.DATA_UPLOAD_MAX_MEMORY_SIZE
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):
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raise RequestDataTooBig(
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"Request body exceeded "
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"settings.DATA_UPLOAD_MAX_MEMORY_SIZE."
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)
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self._post.appendlist(
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field_name, force_str(data, encoding, errors="replace")
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)
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elif item_type == FILE:
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# Avoid storing more than DATA_UPLOAD_MAX_NUMBER_FILES.
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num_files += 1
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if (
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settings.DATA_UPLOAD_MAX_NUMBER_FILES is not None
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and num_files > settings.DATA_UPLOAD_MAX_NUMBER_FILES
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):
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raise TooManyFilesSent(
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"The number of files exceeded "
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"settings.DATA_UPLOAD_MAX_NUMBER_FILES."
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)
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# This is a file, use the handler...
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file_name = disposition.get("filename")
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if file_name:
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file_name = force_str(file_name, encoding, errors="replace")
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file_name = self.sanitize_file_name(file_name)
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if not file_name:
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continue
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content_type, content_type_extra = meta_data.get(
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"content-type", ("", {})
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)
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content_type = content_type.strip()
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charset = content_type_extra.get("charset")
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try:
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content_length = int(meta_data.get("content-length")[0])
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except (IndexError, TypeError, ValueError):
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content_length = None
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counters = [0] * len(handlers)
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uploaded_file = False
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try:
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for handler in handlers:
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try:
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handler.new_file(
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field_name,
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file_name,
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content_type,
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content_length,
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charset,
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content_type_extra,
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)
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except StopFutureHandlers:
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break
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for chunk in field_stream:
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if transfer_encoding == "base64":
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# We only special-case base64 transfer encoding
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# We should always decode base64 chunks by
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# multiple of 4, ignoring whitespace.
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stripped_chunk = b"".join(chunk.split())
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remaining = len(stripped_chunk) % 4
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while remaining != 0:
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over_chunk = field_stream.read(4 - remaining)
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if not over_chunk:
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break
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stripped_chunk += b"".join(over_chunk.split())
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remaining = len(stripped_chunk) % 4
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try:
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chunk = base64.b64decode(stripped_chunk)
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except Exception as exc:
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# Since this is only a chunk, any error is
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# an unfixable error.
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raise MultiPartParserError(
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"Could not decode base64 data."
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) from exc
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for i, handler in enumerate(handlers):
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chunk_length = len(chunk)
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chunk = handler.receive_data_chunk(chunk, counters[i])
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counters[i] += chunk_length
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if chunk is None:
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# Don't continue if the chunk received by
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# the handler is None.
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break
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except SkipFile:
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self._close_files()
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# Just use up the rest of this file...
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exhaust(field_stream)
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else:
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# Handle file upload completions on next iteration.
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old_field_name = field_name
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else:
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# If this is neither a FIELD nor a FILE, exhaust the field
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# stream. Note: There could be an error here at some point,
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# but there will be at least two RAW types (before and
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# after the other boundaries). This branch is usually not
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# reached at all, because a missing content-disposition
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# header will skip the whole boundary.
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exhaust(field_stream)
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except StopUpload as e:
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self._close_files()
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if not e.connection_reset:
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exhaust(self._input_data)
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else:
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if not uploaded_file:
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for handler in handlers:
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handler.upload_interrupted()
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# Make sure that the request data is all fed
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exhaust(self._input_data)
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# Signal that the upload has completed.
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# any() shortcircuits if a handler's upload_complete() returns a value.
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any(handler.upload_complete() for handler in handlers)
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self._post._mutable = False
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return self._post, self._files
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def handle_file_complete(self, old_field_name, counters):
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"""
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Handle all the signaling that takes place when a file is complete.
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"""
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for i, handler in enumerate(self._upload_handlers):
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file_obj = handler.file_complete(counters[i])
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if file_obj:
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# If it returns a file object, then set the files dict.
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self._files.appendlist(
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force_str(old_field_name, self._encoding, errors="replace"),
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file_obj,
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)
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break
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def sanitize_file_name(self, file_name):
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"""
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Sanitize the filename of an upload.
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Remove all possible path separators, even though that might remove more
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|
|
than actually required by the target system. Filenames that could
|
||
|
|
potentially cause problems (current/parent dir) are also discarded.
|
||
|
|
|
||
|
|
It should be noted that this function could still return a "filepath"
|
||
|
|
like "C:some_file.txt" which is handled later on by the storage layer.
|
||
|
|
So while this function does sanitize filenames to some extent, the
|
||
|
|
resulting filename should still be considered as untrusted user input.
|
||
|
|
"""
|
||
|
|
file_name = html.unescape(file_name)
|
||
|
|
file_name = file_name.rsplit("/")[-1]
|
||
|
|
file_name = file_name.rsplit("\\")[-1]
|
||
|
|
# Remove non-printable characters.
|
||
|
|
file_name = "".join([char for char in file_name if char.isprintable()])
|
||
|
|
|
||
|
|
if file_name in {"", ".", ".."}:
|
||
|
|
return None
|
||
|
|
return file_name
|
||
|
|
|
||
|
|
IE_sanitize = sanitize_file_name
|
||
|
|
|
||
|
|
def _close_files(self):
|
||
|
|
# Free up all file handles.
|
||
|
|
# FIXME: this currently assumes that upload handlers store the file as 'file'
|
||
|
|
# We should document that...
|
||
|
|
# (Maybe add handler.free_file to complement new_file)
|
||
|
|
for handler in self._upload_handlers:
|
||
|
|
if hasattr(handler, "file"):
|
||
|
|
handler.file.close()
|
||
|
|
|
||
|
|
|
||
|
|
class LazyStream:
|
||
|
|
"""
|
||
|
|
The LazyStream wrapper allows one to get and "unget" bytes from a stream.
|
||
|
|
|
||
|
|
Given a producer object (an iterator that yields bytestrings), the
|
||
|
|
LazyStream object will support iteration, reading, and keeping a "look-back"
|
||
|
|
variable in case you need to "unget" some bytes.
|
||
|
|
"""
|
||
|
|
|
||
|
|
def __init__(self, producer, length=None):
|
||
|
|
"""
|
||
|
|
Every LazyStream must have a producer when instantiated.
|
||
|
|
|
||
|
|
A producer is an iterable that returns a string each time it
|
||
|
|
is called.
|
||
|
|
"""
|
||
|
|
self._producer = producer
|
||
|
|
self._empty = False
|
||
|
|
self._leftover = b""
|
||
|
|
self.length = length
|
||
|
|
self.position = 0
|
||
|
|
self._remaining = length
|
||
|
|
self._unget_history = []
|
||
|
|
|
||
|
|
def tell(self):
|
||
|
|
return self.position
|
||
|
|
|
||
|
|
def read(self, size=None):
|
||
|
|
def parts():
|
||
|
|
remaining = self._remaining if size is None else size
|
||
|
|
# do the whole thing in one shot if no limit was provided.
|
||
|
|
if remaining is None:
|
||
|
|
yield b"".join(self)
|
||
|
|
return
|
||
|
|
|
||
|
|
# otherwise do some bookkeeping to return exactly enough
|
||
|
|
# of the stream and stashing any extra content we get from
|
||
|
|
# the producer
|
||
|
|
while remaining != 0:
|
||
|
|
assert remaining > 0, "remaining bytes to read should never go negative"
|
||
|
|
|
||
|
|
try:
|
||
|
|
chunk = next(self)
|
||
|
|
except StopIteration:
|
||
|
|
return
|
||
|
|
else:
|
||
|
|
emitting = chunk[:remaining]
|
||
|
|
self.unget(chunk[remaining:])
|
||
|
|
remaining -= len(emitting)
|
||
|
|
yield emitting
|
||
|
|
|
||
|
|
return b"".join(parts())
|
||
|
|
|
||
|
|
def __next__(self):
|
||
|
|
"""
|
||
|
|
Used when the exact number of bytes to read is unimportant.
|
||
|
|
|
||
|
|
Return whatever chunk is conveniently returned from the iterator.
|
||
|
|
Useful to avoid unnecessary bookkeeping if performance is an issue.
|
||
|
|
"""
|
||
|
|
if self._leftover:
|
||
|
|
output = self._leftover
|
||
|
|
self._leftover = b""
|
||
|
|
else:
|
||
|
|
output = next(self._producer)
|
||
|
|
self._unget_history = []
|
||
|
|
self.position += len(output)
|
||
|
|
return output
|
||
|
|
|
||
|
|
def close(self):
|
||
|
|
"""
|
||
|
|
Used to invalidate/disable this lazy stream.
|
||
|
|
|
||
|
|
Replace the producer with an empty list. Any leftover bytes that have
|
||
|
|
already been read will still be reported upon read() and/or next().
|
||
|
|
"""
|
||
|
|
self._producer = []
|
||
|
|
|
||
|
|
def __iter__(self):
|
||
|
|
return self
|
||
|
|
|
||
|
|
def unget(self, bytes):
|
||
|
|
"""
|
||
|
|
Place bytes back onto the front of the lazy stream.
|
||
|
|
|
||
|
|
Future calls to read() will return those bytes first. The
|
||
|
|
stream position and thus tell() will be rewound.
|
||
|
|
"""
|
||
|
|
if not bytes:
|
||
|
|
return
|
||
|
|
self._update_unget_history(len(bytes))
|
||
|
|
self.position -= len(bytes)
|
||
|
|
self._leftover = bytes + self._leftover
|
||
|
|
|
||
|
|
def _update_unget_history(self, num_bytes):
|
||
|
|
"""
|
||
|
|
Update the unget history as a sanity check to see if we've pushed
|
||
|
|
back the same number of bytes in one chunk. If we keep ungetting the
|
||
|
|
same number of bytes many times (here, 50), we're mostly likely in an
|
||
|
|
infinite loop of some sort. This is usually caused by a
|
||
|
|
maliciously-malformed MIME request.
|
||
|
|
"""
|
||
|
|
self._unget_history = [num_bytes] + self._unget_history[:49]
|
||
|
|
number_equal = len(
|
||
|
|
[
|
||
|
|
current_number
|
||
|
|
for current_number in self._unget_history
|
||
|
|
if current_number == num_bytes
|
||
|
|
]
|
||
|
|
)
|
||
|
|
|
||
|
|
if number_equal > 40:
|
||
|
|
raise SuspiciousMultipartForm(
|
||
|
|
"The multipart parser got stuck, which shouldn't happen with"
|
||
|
|
" normal uploaded files. Check for malicious upload activity;"
|
||
|
|
" if there is none, report this to the Django developers."
|
||
|
|
)
|
||
|
|
|
||
|
|
|
||
|
|
class ChunkIter:
|
||
|
|
"""
|
||
|
|
An iterable that will yield chunks of data. Given a file-like object as the
|
||
|
|
constructor, yield chunks of read operations from that object.
|
||
|
|
"""
|
||
|
|
|
||
|
|
def __init__(self, flo, chunk_size=64 * 1024):
|
||
|
|
self.flo = flo
|
||
|
|
self.chunk_size = chunk_size
|
||
|
|
|
||
|
|
def __next__(self):
|
||
|
|
try:
|
||
|
|
data = self.flo.read(self.chunk_size)
|
||
|
|
except InputStreamExhausted:
|
||
|
|
raise StopIteration()
|
||
|
|
if data:
|
||
|
|
return data
|
||
|
|
else:
|
||
|
|
raise StopIteration()
|
||
|
|
|
||
|
|
def __iter__(self):
|
||
|
|
return self
|
||
|
|
|
||
|
|
|
||
|
|
class InterBoundaryIter:
|
||
|
|
"""
|
||
|
|
A Producer that will iterate over boundaries.
|
||
|
|
"""
|
||
|
|
|
||
|
|
def __init__(self, stream, boundary):
|
||
|
|
self._stream = stream
|
||
|
|
self._boundary = boundary
|
||
|
|
|
||
|
|
def __iter__(self):
|
||
|
|
return self
|
||
|
|
|
||
|
|
def __next__(self):
|
||
|
|
try:
|
||
|
|
return LazyStream(BoundaryIter(self._stream, self._boundary))
|
||
|
|
except InputStreamExhausted:
|
||
|
|
raise StopIteration()
|
||
|
|
|
||
|
|
|
||
|
|
class BoundaryIter:
|
||
|
|
"""
|
||
|
|
A Producer that is sensitive to boundaries.
|
||
|
|
|
||
|
|
Will happily yield bytes until a boundary is found. Will yield the bytes
|
||
|
|
before the boundary, throw away the boundary bytes themselves, and push the
|
||
|
|
post-boundary bytes back on the stream.
|
||
|
|
|
||
|
|
The future calls to next() after locating the boundary will raise a
|
||
|
|
StopIteration exception.
|
||
|
|
"""
|
||
|
|
|
||
|
|
def __init__(self, stream, boundary):
|
||
|
|
self._stream = stream
|
||
|
|
self._boundary = boundary
|
||
|
|
self._done = False
|
||
|
|
# rollback an additional six bytes because the format is like
|
||
|
|
# this: CRLF<boundary>[--CRLF]
|
||
|
|
self._rollback = len(boundary) + 6
|
||
|
|
|
||
|
|
# Try to use mx fast string search if available. Otherwise
|
||
|
|
# use Python find. Wrap the latter for consistency.
|
||
|
|
unused_char = self._stream.read(1)
|
||
|
|
if not unused_char:
|
||
|
|
raise InputStreamExhausted()
|
||
|
|
self._stream.unget(unused_char)
|
||
|
|
|
||
|
|
def __iter__(self):
|
||
|
|
return self
|
||
|
|
|
||
|
|
def __next__(self):
|
||
|
|
if self._done:
|
||
|
|
raise StopIteration()
|
||
|
|
|
||
|
|
stream = self._stream
|
||
|
|
rollback = self._rollback
|
||
|
|
|
||
|
|
bytes_read = 0
|
||
|
|
chunks = []
|
||
|
|
for bytes in stream:
|
||
|
|
bytes_read += len(bytes)
|
||
|
|
chunks.append(bytes)
|
||
|
|
if bytes_read > rollback:
|
||
|
|
break
|
||
|
|
if not bytes:
|
||
|
|
break
|
||
|
|
else:
|
||
|
|
self._done = True
|
||
|
|
|
||
|
|
if not chunks:
|
||
|
|
raise StopIteration()
|
||
|
|
|
||
|
|
chunk = b"".join(chunks)
|
||
|
|
boundary = self._find_boundary(chunk)
|
||
|
|
|
||
|
|
if boundary:
|
||
|
|
end, next = boundary
|
||
|
|
stream.unget(chunk[next:])
|
||
|
|
self._done = True
|
||
|
|
return chunk[:end]
|
||
|
|
else:
|
||
|
|
# make sure we don't treat a partial boundary (and
|
||
|
|
# its separators) as data
|
||
|
|
if not chunk[:-rollback]: # and len(chunk) >= (len(self._boundary) + 6):
|
||
|
|
# There's nothing left, we should just return and mark as done.
|
||
|
|
self._done = True
|
||
|
|
return chunk
|
||
|
|
else:
|
||
|
|
stream.unget(chunk[-rollback:])
|
||
|
|
return chunk[:-rollback]
|
||
|
|
|
||
|
|
def _find_boundary(self, data):
|
||
|
|
"""
|
||
|
|
Find a multipart boundary in data.
|
||
|
|
|
||
|
|
Should no boundary exist in the data, return None. Otherwise, return
|
||
|
|
a tuple containing the indices of the following:
|
||
|
|
* the end of current encapsulation
|
||
|
|
* the start of the next encapsulation
|
||
|
|
"""
|
||
|
|
index = data.find(self._boundary)
|
||
|
|
if index < 0:
|
||
|
|
return None
|
||
|
|
else:
|
||
|
|
end = index
|
||
|
|
next = index + len(self._boundary)
|
||
|
|
# backup over CRLF
|
||
|
|
last = max(0, end - 1)
|
||
|
|
if data[last : last + 1] == b"\n":
|
||
|
|
end -= 1
|
||
|
|
last = max(0, end - 1)
|
||
|
|
if data[last : last + 1] == b"\r":
|
||
|
|
end -= 1
|
||
|
|
return end, next
|
||
|
|
|
||
|
|
|
||
|
|
def exhaust(stream_or_iterable):
|
||
|
|
"""Exhaust an iterator or stream."""
|
||
|
|
try:
|
||
|
|
iterator = iter(stream_or_iterable)
|
||
|
|
except TypeError:
|
||
|
|
iterator = ChunkIter(stream_or_iterable, 16384)
|
||
|
|
collections.deque(iterator, maxlen=0) # consume iterator quickly.
|
||
|
|
|
||
|
|
|
||
|
|
def parse_boundary_stream(stream, max_header_size):
|
||
|
|
"""
|
||
|
|
Parse one and exactly one stream that encapsulates a boundary.
|
||
|
|
"""
|
||
|
|
# Stream at beginning of header, look for end of header
|
||
|
|
# and parse it if found. The header must fit within one
|
||
|
|
# chunk.
|
||
|
|
chunk = stream.read(max_header_size)
|
||
|
|
|
||
|
|
# 'find' returns the top of these four bytes, so we'll
|
||
|
|
# need to munch them later to prevent them from polluting
|
||
|
|
# the payload.
|
||
|
|
header_end = chunk.find(b"\r\n\r\n")
|
||
|
|
|
||
|
|
if header_end == -1:
|
||
|
|
# we find no header, so we just mark this fact and pass on
|
||
|
|
# the stream verbatim
|
||
|
|
stream.unget(chunk)
|
||
|
|
return (RAW, {}, stream)
|
||
|
|
|
||
|
|
header = chunk[:header_end]
|
||
|
|
|
||
|
|
# here we place any excess chunk back onto the stream, as
|
||
|
|
# well as throwing away the CRLFCRLF bytes from above.
|
||
|
|
stream.unget(chunk[header_end + 4 :])
|
||
|
|
|
||
|
|
TYPE = RAW
|
||
|
|
outdict = {}
|
||
|
|
|
||
|
|
# Eliminate blank lines
|
||
|
|
for line in header.split(b"\r\n"):
|
||
|
|
# This terminology ("main value" and "dictionary of
|
||
|
|
# parameters") is from the Python docs.
|
||
|
|
try:
|
||
|
|
main_value_pair, params = parse_header_parameters(line.decode())
|
||
|
|
name, value = main_value_pair.split(":", 1)
|
||
|
|
params = {k: v.encode() for k, v in params.items()}
|
||
|
|
except ValueError: # Invalid header.
|
||
|
|
continue
|
||
|
|
|
||
|
|
if name == "content-disposition":
|
||
|
|
TYPE = FIELD
|
||
|
|
if params.get("filename"):
|
||
|
|
TYPE = FILE
|
||
|
|
|
||
|
|
outdict[name] = value, params
|
||
|
|
|
||
|
|
if TYPE == RAW:
|
||
|
|
stream.unget(chunk)
|
||
|
|
|
||
|
|
return (TYPE, outdict, stream)
|
||
|
|
|
||
|
|
|
||
|
|
class Parser:
|
||
|
|
def __init__(self, stream, boundary):
|
||
|
|
self._stream = stream
|
||
|
|
self._separator = b"--" + boundary
|
||
|
|
|
||
|
|
def __iter__(self):
|
||
|
|
boundarystream = InterBoundaryIter(self._stream, self._separator)
|
||
|
|
for sub_stream in boundarystream:
|
||
|
|
# Iterate over each part
|
||
|
|
yield parse_boundary_stream(sub_stream, 1024)
|