2025-12-25 upload
This commit is contained in:
23
venv/Lib/site-packages/hpack/__init__.py
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23
venv/Lib/site-packages/hpack/__init__.py
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"""
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HTTP/2 header encoding for Python.
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"""
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from __future__ import annotations
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from .exceptions import HPACKDecodingError, HPACKError, InvalidTableIndex, InvalidTableIndexError, InvalidTableSizeError, OversizedHeaderListError
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from .hpack import Decoder, Encoder
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from .struct import HeaderTuple, NeverIndexedHeaderTuple
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__all__ = [
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"Decoder",
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"Encoder",
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"HPACKDecodingError",
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"HPACKError",
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"HeaderTuple",
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"InvalidTableIndex",
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"InvalidTableIndexError",
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"InvalidTableSizeError",
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"NeverIndexedHeaderTuple",
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"OversizedHeaderListError",
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]
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__version__ = "4.1.0"
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53
venv/Lib/site-packages/hpack/exceptions.py
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53
venv/Lib/site-packages/hpack/exceptions.py
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"""
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Exceptions used in hpack.
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"""
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from __future__ import annotations
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class HPACKError(Exception):
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"""
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The base class for all ``hpack`` exceptions.
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"""
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class HPACKDecodingError(HPACKError):
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"""
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An error has been encountered while performing HPACK decoding.
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"""
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class InvalidTableIndexError(HPACKDecodingError):
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"""
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An invalid table index was received.
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.. versionadded:: 4.1.0
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"""
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class InvalidTableIndex(InvalidTableIndexError): # noqa: N818
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"""
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An invalid table index was received.
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.. deprecated:: 4.1.0
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Renamed to :class:`InvalidTableIndexError`, use it instead.
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"""
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class OversizedHeaderListError(HPACKDecodingError):
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"""
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A header list that was larger than we allow has been received. This may be
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a DoS attack.
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.. versionadded:: 2.3.0
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"""
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class InvalidTableSizeError(HPACKDecodingError):
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"""
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An attempt was made to change the decoder table size to a value larger than
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allowed, or the list was shrunk and the remote peer didn't shrink their
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table size.
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.. versionadded:: 3.0.0
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"""
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654
venv/Lib/site-packages/hpack/hpack.py
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654
venv/Lib/site-packages/hpack/hpack.py
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"""
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Implements the HPACK header compression algorithm as detailed by RFC 7541.
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"""
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from __future__ import annotations
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import logging
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from typing import TYPE_CHECKING, Any
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from .exceptions import HPACKDecodingError, InvalidTableSizeError, OversizedHeaderListError
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from .huffman import HuffmanEncoder
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from .huffman_constants import REQUEST_CODES, REQUEST_CODES_LENGTH
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from .huffman_table import decode_huffman
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from .struct import HeaderTuple, HeaderWeaklyTyped, NeverIndexedHeaderTuple
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from .table import HeaderTable, table_entry_size
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if TYPE_CHECKING:
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from collections.abc import Iterable # pragma: no cover
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log = logging.getLogger(__name__)
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INDEX_NONE = b"\x00"
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INDEX_NEVER = b"\x10"
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INDEX_INCREMENTAL = b"\x40"
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# Precompute 2^i for 1-8 for use in prefix calcs.
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# Zero index is not used but there to save a subtraction
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# as prefix numbers are not zero indexed.
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_PREFIX_BIT_MAX_NUMBERS = [(2 ** i) - 1 for i in range(9)]
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# We default the maximum header list we're willing to accept to 64kB. That's a
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# lot of headers, but if applications want to raise it they can do.
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DEFAULT_MAX_HEADER_LIST_SIZE = 2 ** 16
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def _unicode_if_needed(header: HeaderWeaklyTyped, raw: bool) -> HeaderTuple:
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"""
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Provides a header as a unicode string if raw is False, otherwise returns
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it as a bytestring.
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"""
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name = bytes(header[0]) # type: ignore
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value = bytes(header[1]) # type: ignore
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if not raw:
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return header.__class__(name.decode("utf-8"), value.decode("utf-8")) # type: ignore
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return header.__class__(name, value) # type: ignore
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def encode_integer(integer: int, prefix_bits: int) -> bytearray:
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"""
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Encodes an integer according to the wacky integer encoding rules
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defined in the HPACK spec.
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"""
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log.debug("Encoding %d with %d bits", integer, prefix_bits)
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if integer < 0:
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msg = f"Can only encode positive integers, got {integer}"
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raise ValueError(msg)
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if prefix_bits < 1 or prefix_bits > 8:
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msg = f"Prefix bits must be between 1 and 8, got {prefix_bits}"
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raise ValueError(msg)
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max_number = _PREFIX_BIT_MAX_NUMBERS[prefix_bits]
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if integer < max_number:
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return bytearray([integer]) # Seriously?
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elements = [max_number]
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integer -= max_number
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while integer >= 128:
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elements.append((integer & 127) + 128)
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integer >>= 7
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elements.append(integer)
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return bytearray(elements)
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def decode_integer(data: bytes, prefix_bits: int) -> tuple[int, int]:
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"""
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Decodes an integer according to the wacky integer encoding rules
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defined in the HPACK spec. Returns a tuple of the decoded integer and the
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number of bytes that were consumed from ``data`` in order to get that
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integer.
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"""
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if prefix_bits < 1 or prefix_bits > 8:
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msg = f"Prefix bits must be between 1 and 8, got {prefix_bits}"
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raise ValueError(msg)
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max_number = _PREFIX_BIT_MAX_NUMBERS[prefix_bits]
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index = 1
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shift = 0
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mask = (0xFF >> (8 - prefix_bits))
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try:
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number = data[0] & mask
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if number == max_number:
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while True:
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next_byte = data[index]
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index += 1
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if next_byte >= 128:
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number += (next_byte - 128) << shift
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else:
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number += next_byte << shift
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break
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shift += 7
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except IndexError as err:
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msg = f"Unable to decode HPACK integer representation from {data!r}"
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raise HPACKDecodingError(msg) from err
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log.debug("Decoded %d, consumed %d bytes", number, index)
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return number, index
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def _dict_to_iterable(header_dict: dict[bytes | str, bytes | str]) \
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-> Iterable[tuple[bytes | str, bytes | str]]:
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"""
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Converts a dictionary to an iterable of key-value tuples. This is a
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HPACK-specific function because it pulls "special-headers" out first and
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then emits them.
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"""
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if not isinstance(header_dict, dict): # pragma: no cover
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msg = f"header_dict not a dict, but {type(header_dict)}"
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raise TypeError(msg)
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keys = sorted(
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header_dict.keys(),
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key=lambda k: not _to_bytes(k).startswith(b":"),
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)
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for key in keys:
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yield key, header_dict[key]
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def _to_bytes(value: bytes | str | Any) -> bytes:
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"""
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Convert anything to bytes through a UTF-8 encoded string
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"""
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t = type(value)
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if t is bytes:
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return value # type: ignore
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if t is not str:
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value = str(value)
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return value.encode("utf-8") # type: ignore
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class Encoder:
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"""
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An HPACK encoder object. This object takes HTTP headers and emits encoded
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HTTP/2 header blocks.
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"""
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def __init__(self) -> None:
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self.header_table = HeaderTable()
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self.huffman_coder = HuffmanEncoder(
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REQUEST_CODES, REQUEST_CODES_LENGTH,
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)
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self.table_size_changes: list[int] = []
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@property
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def header_table_size(self) -> int:
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"""
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Controls the size of the HPACK header table.
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"""
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return self.header_table.maxsize
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@header_table_size.setter
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def header_table_size(self, value: int) -> None:
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self.header_table.maxsize = value
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if self.header_table.resized:
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self.table_size_changes.append(value)
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def encode(self,
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headers: Iterable[\
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HeaderTuple | \
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tuple[bytes | str, bytes | str] | \
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tuple[bytes | str, bytes | str, bool | None]] | \
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dict[bytes | str, bytes | str],
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huffman: bool = True) -> bytes:
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"""
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Takes a set of headers and encodes them into a HPACK-encoded header
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block.
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:param headers: The headers to encode. Must be either an iterable of
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tuples, an iterable of :class:`HeaderTuple
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<hpack.HeaderTuple>`, or a ``dict``.
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If an iterable of tuples, the tuples may be either
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two-tuples or three-tuples. If they are two-tuples, the
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tuples must be of the format ``(name, value)``. If they
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are three-tuples, they must be of the format
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``(name, value, sensitive)``, where ``sensitive`` is a
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boolean value indicating whether the header should be
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added to header tables anywhere. If not present,
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``sensitive`` defaults to ``False``.
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If an iterable of :class:`HeaderTuple
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<hpack.HeaderTuple>`, the tuples must always be
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two-tuples. Instead of using ``sensitive`` as a third
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tuple entry, use :class:`NeverIndexedHeaderTuple
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<hpack.NeverIndexedHeaderTuple>` to request that
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the field never be indexed.
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.. warning:: HTTP/2 requires that all special headers
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(headers whose names begin with ``:`` characters)
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appear at the *start* of the header block. While
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this method will ensure that happens for ``dict``
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subclasses, callers using any other iterable of
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tuples **must** ensure they place their special
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headers at the start of the iterable.
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For efficiency reasons users should prefer to use
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iterables of two-tuples: fixing the ordering of
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dictionary headers is an expensive operation that
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should be avoided if possible.
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:param huffman: (optional) Whether to Huffman-encode any header sent as
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a literal value. Except for use when debugging, it is
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recommended that this be left enabled.
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:returns: A bytestring containing the HPACK-encoded header block.
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"""
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# Transforming the headers into a header block is a procedure that can
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# be modeled as a chain or pipe. First, the headers are encoded. This
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# encoding can be done a number of ways. If the header name-value pair
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# are already in the header table we can represent them using the
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# indexed representation: the same is true if they are in the static
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# table. Otherwise, a literal representation will be used.
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header_block = []
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# Before we begin, if the header table size has been changed we need
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# to signal all changes since last emission appropriately.
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if self.header_table.resized:
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header_block.append(self._encode_table_size_change())
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self.header_table.resized = False
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if isinstance(headers, dict):
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# Turn the headers into a list of tuples if possible. This is the
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# natural way to interact with them in HPACK. Because dictionaries are
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# un-ordered, we need to make sure we grab the "special" headers first.
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hpack_headers = _dict_to_iterable(headers)
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else:
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"""
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Assume headers is an iterable of HeaderTuples, or plain 2-tuples, or plain 3-tuples:
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examples:
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[
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HeaderTuple(':method', 'GET'),
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NeverIndexedHeaderTuple('customkey', 'sensitiveinfo'),
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]
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or
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[
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(':method', 'GET'),
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('customkey', 'some-data'),
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]
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or
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[
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(':method', 'GET', True),
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('customkey', 'sensitiveinfo', True),
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]
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"""
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hpack_headers = iter(headers) # type: ignore
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# Add each header to the header block
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for header in hpack_headers:
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sensitive = False
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if isinstance(header, HeaderTuple):
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# HeaderTuple implies it's a 2-tuple with the sensitive information stored as instance attribute
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sensitive = not header.indexable
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elif len(header) > 2:
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sensitive = header[2]
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new_header = (_to_bytes(header[0]), _to_bytes(header[1]))
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header_block.append(self.add(new_header, sensitive, huffman))
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encoded = b"".join(header_block)
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log.debug("Encoded header block to %s", encoded)
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return encoded
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def add(self, to_add: tuple[bytes, bytes], sensitive: bool, huffman: bool = False) -> bytes:
|
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"""
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Serializes a header key-value tuple.
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"""
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log.debug(
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"Adding %s to the header table, sensitive:%s, huffman:%s",
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to_add,
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sensitive,
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huffman,
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)
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name, value = to_add
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# Set our indexing mode
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indexbit = INDEX_INCREMENTAL if not sensitive else INDEX_NEVER
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# Search for a matching header in the header table.
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match = self.header_table.search(name, value)
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if match is None:
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# Not in the header table. Encode using the literal syntax,
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# and add it to the header table.
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encoded = self._encode_literal(name, value, indexbit, huffman)
|
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if not sensitive:
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self.header_table.add(name, value)
|
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return encoded
|
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|
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# The header is in the table, break out the values. If we matched
|
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# perfectly, we can use the indexed representation: otherwise we
|
||||
# can use the indexed literal.
|
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index, name, perfect = match
|
||||
|
||||
if perfect:
|
||||
# Indexed representation.
|
||||
encoded = self._encode_indexed(index)
|
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else:
|
||||
# Indexed literal. We are going to add header to the
|
||||
# header table unconditionally. It is a future todo to
|
||||
# filter out headers which are known to be ineffective for
|
||||
# indexing since they just take space in the table and
|
||||
# pushed out other valuable headers.
|
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encoded = self._encode_indexed_literal(
|
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index, value, indexbit, huffman,
|
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)
|
||||
if not sensitive:
|
||||
self.header_table.add(name, value)
|
||||
|
||||
return encoded
|
||||
|
||||
def _encode_indexed(self, index: int) -> bytes:
|
||||
"""
|
||||
Encodes a header using the indexed representation.
|
||||
"""
|
||||
field = encode_integer(index, 7)
|
||||
field[0] |= 0x80 # we set the top bit
|
||||
return bytes(field)
|
||||
|
||||
def _encode_literal(self, name: bytes, value: bytes, indexbit: bytes, huffman: bool = False) -> bytes:
|
||||
"""
|
||||
Encodes a header with a literal name and literal value. If ``indexing``
|
||||
is True, the header will be added to the header table: otherwise it
|
||||
will not.
|
||||
"""
|
||||
if huffman:
|
||||
name = self.huffman_coder.encode(name)
|
||||
value = self.huffman_coder.encode(value)
|
||||
|
||||
name_len = encode_integer(len(name), 7)
|
||||
value_len = encode_integer(len(value), 7)
|
||||
|
||||
if huffman:
|
||||
name_len[0] |= 0x80
|
||||
value_len[0] |= 0x80
|
||||
|
||||
return b"".join(
|
||||
[indexbit, bytes(name_len), name, bytes(value_len), value],
|
||||
)
|
||||
|
||||
def _encode_indexed_literal(self, index: int, value: bytes, indexbit: bytes, huffman: bool = False) -> bytes:
|
||||
"""
|
||||
Encodes a header with an indexed name and a literal value and performs
|
||||
incremental indexing.
|
||||
"""
|
||||
if indexbit != INDEX_INCREMENTAL:
|
||||
prefix = encode_integer(index, 4)
|
||||
else:
|
||||
prefix = encode_integer(index, 6)
|
||||
|
||||
prefix[0] |= ord(indexbit)
|
||||
|
||||
if huffman:
|
||||
value = self.huffman_coder.encode(value)
|
||||
|
||||
value_len = encode_integer(len(value), 7)
|
||||
|
||||
if huffman:
|
||||
value_len[0] |= 0x80
|
||||
|
||||
return b"".join([bytes(prefix), bytes(value_len), value])
|
||||
|
||||
def _encode_table_size_change(self) -> bytes:
|
||||
"""
|
||||
Produces the encoded form of all header table size change context
|
||||
updates.
|
||||
"""
|
||||
block = b""
|
||||
for size_bytes in self.table_size_changes:
|
||||
b = encode_integer(size_bytes, 5)
|
||||
b[0] |= 0x20
|
||||
block += bytes(b)
|
||||
self.table_size_changes = []
|
||||
return block
|
||||
|
||||
|
||||
class Decoder:
|
||||
"""
|
||||
An HPACK decoder object.
|
||||
|
||||
.. versionchanged:: 2.3.0
|
||||
Added ``max_header_list_size`` argument.
|
||||
|
||||
:param max_header_list_size: The maximum decompressed size we will allow
|
||||
for any single header block. This is a protection against DoS attacks
|
||||
that attempt to force the application to expand a relatively small
|
||||
amount of data into a really large header list, allowing enormous
|
||||
amounts of memory to be allocated.
|
||||
|
||||
If this amount of data is exceeded, a `OversizedHeaderListError
|
||||
<hpack.OversizedHeaderListError>` exception will be raised. At this
|
||||
point the connection should be shut down, as the HPACK state will no
|
||||
longer be usable.
|
||||
|
||||
Defaults to 64kB.
|
||||
:type max_header_list_size: ``int``
|
||||
"""
|
||||
|
||||
def __init__(self, max_header_list_size: int = DEFAULT_MAX_HEADER_LIST_SIZE) -> None:
|
||||
self.header_table = HeaderTable()
|
||||
|
||||
#: The maximum decompressed size we will allow for any single header
|
||||
#: block. This is a protection against DoS attacks that attempt to
|
||||
#: force the application to expand a relatively small amount of data
|
||||
#: into a really large header list, allowing enormous amounts of memory
|
||||
#: to be allocated.
|
||||
#:
|
||||
#: If this amount of data is exceeded, a `OversizedHeaderListError
|
||||
#: <hpack.OversizedHeaderListError>` exception will be raised. At this
|
||||
#: point the connection should be shut down, as the HPACK state will no
|
||||
#: longer be usable.
|
||||
#:
|
||||
#: Defaults to 64kB.
|
||||
#:
|
||||
#: .. versionadded:: 2.3.0
|
||||
self.max_header_list_size = max_header_list_size
|
||||
|
||||
#: Maximum allowed header table size.
|
||||
#:
|
||||
#: A HTTP/2 implementation should set this to the most recent value of
|
||||
#: SETTINGS_HEADER_TABLE_SIZE that it sent *and has received an ACK
|
||||
#: for*. Once this setting is set, the actual header table size will be
|
||||
#: checked at the end of each decoding run and whenever it is changed,
|
||||
#: to confirm that it fits in this size.
|
||||
self.max_allowed_table_size = self.header_table.maxsize
|
||||
|
||||
@property
|
||||
def header_table_size(self) -> int:
|
||||
"""
|
||||
Controls the size of the HPACK header table.
|
||||
"""
|
||||
return self.header_table.maxsize
|
||||
|
||||
@header_table_size.setter
|
||||
def header_table_size(self, value: int) -> None:
|
||||
self.header_table.maxsize = value
|
||||
|
||||
def decode(self, data: bytes, raw: bool = False) -> Iterable[HeaderTuple]:
|
||||
"""
|
||||
Takes an HPACK-encoded header block and decodes it into a header set.
|
||||
|
||||
:param data: A bytestring representing a complete HPACK-encoded header
|
||||
block.
|
||||
:param raw: (optional) Whether to return the headers as tuples of raw
|
||||
byte strings or to decode them as UTF-8 before returning
|
||||
them. The default value is False, which returns tuples of
|
||||
Unicode strings
|
||||
:returns: A list of two-tuples of ``(name, value)`` representing the
|
||||
HPACK-encoded headers, in the order they were decoded.
|
||||
:raises HPACKDecodingError: If an error is encountered while decoding
|
||||
the header block.
|
||||
"""
|
||||
log.debug("Decoding %s", data)
|
||||
|
||||
data_mem = memoryview(data)
|
||||
headers: list[HeaderTuple] = []
|
||||
data_len = len(data)
|
||||
inflated_size = 0
|
||||
current_index = 0
|
||||
|
||||
while current_index < data_len:
|
||||
# Work out what kind of header we're decoding.
|
||||
# If the high bit is 1, it's an indexed field.
|
||||
current = data[current_index]
|
||||
indexed = bool(current & 0x80)
|
||||
|
||||
# Otherwise, if the second-highest bit is 1 it's a field that does
|
||||
# alter the header table.
|
||||
literal_index = bool(current & 0x40)
|
||||
|
||||
# Otherwise, if the third-highest bit is 1 it's an encoding context
|
||||
# update.
|
||||
encoding_update = bool(current & 0x20)
|
||||
|
||||
if indexed:
|
||||
header, consumed = self._decode_indexed(
|
||||
data_mem[current_index:],
|
||||
)
|
||||
elif literal_index:
|
||||
# It's a literal header that does affect the header table.
|
||||
header, consumed = self._decode_literal_index(
|
||||
data_mem[current_index:],
|
||||
)
|
||||
elif encoding_update:
|
||||
# It's an update to the encoding context. These are forbidden
|
||||
# in a header block after any actual header.
|
||||
if headers:
|
||||
msg = "Table size update not at the start of the block"
|
||||
raise HPACKDecodingError(msg)
|
||||
consumed = self._update_encoding_context(
|
||||
data_mem[current_index:],
|
||||
)
|
||||
header = None
|
||||
else:
|
||||
# It's a literal header that does not affect the header table.
|
||||
header, consumed = self._decode_literal_no_index(
|
||||
data_mem[current_index:],
|
||||
)
|
||||
|
||||
if header:
|
||||
headers.append(header)
|
||||
inflated_size += table_entry_size(header[0], header[1])
|
||||
|
||||
if inflated_size > self.max_header_list_size:
|
||||
msg = f"A header list larger than {self.max_header_list_size} has been received"
|
||||
raise OversizedHeaderListError(msg)
|
||||
|
||||
current_index += consumed
|
||||
|
||||
# Confirm that the table size is lower than the maximum. We do this
|
||||
# here to ensure that we catch when the max has been *shrunk* and the
|
||||
# remote peer hasn't actually done that.
|
||||
self._assert_valid_table_size()
|
||||
|
||||
try:
|
||||
return [_unicode_if_needed(h, raw) for h in headers]
|
||||
except UnicodeDecodeError as err:
|
||||
msg = "Unable to decode headers as UTF-8"
|
||||
raise HPACKDecodingError(msg) from err
|
||||
|
||||
def _assert_valid_table_size(self) -> None:
|
||||
"""
|
||||
Check that the table size set by the encoder is lower than the maximum
|
||||
we expect to have.
|
||||
"""
|
||||
if self.header_table_size > self.max_allowed_table_size:
|
||||
msg = "Encoder did not shrink table size to within the max"
|
||||
raise InvalidTableSizeError(msg)
|
||||
|
||||
def _update_encoding_context(self, data: bytes) -> int:
|
||||
"""
|
||||
Handles a byte that updates the encoding context.
|
||||
"""
|
||||
# We've been asked to resize the header table.
|
||||
new_size, consumed = decode_integer(data, 5)
|
||||
if new_size > self.max_allowed_table_size:
|
||||
msg = "Encoder exceeded max allowable table size"
|
||||
raise InvalidTableSizeError(msg)
|
||||
self.header_table_size = new_size
|
||||
return consumed
|
||||
|
||||
def _decode_indexed(self, data: bytes) -> tuple[HeaderTuple, int]:
|
||||
"""
|
||||
Decodes a header represented using the indexed representation.
|
||||
"""
|
||||
index, consumed = decode_integer(data, 7)
|
||||
header = HeaderTuple(*self.header_table.get_by_index(index))
|
||||
log.debug("Decoded %s, consumed %d", header, consumed)
|
||||
return header, consumed
|
||||
|
||||
def _decode_literal_no_index(self, data: bytes) -> tuple[HeaderTuple, int]:
|
||||
return self._decode_literal(data, should_index=False)
|
||||
|
||||
def _decode_literal_index(self, data: bytes) -> tuple[HeaderTuple, int]:
|
||||
return self._decode_literal(data, should_index=True)
|
||||
|
||||
def _decode_literal(self, data: bytes, should_index: bool) -> tuple[HeaderTuple, int]:
|
||||
"""
|
||||
Decodes a header represented with a literal.
|
||||
"""
|
||||
total_consumed = 0
|
||||
|
||||
# When should_index is true, if the low six bits of the first byte are
|
||||
# nonzero, the header name is indexed.
|
||||
# When should_index is false, if the low four bits of the first byte
|
||||
# are nonzero the header name is indexed.
|
||||
if should_index:
|
||||
indexed_name = data[0] & 0x3F
|
||||
name_len = 6
|
||||
not_indexable = False
|
||||
else:
|
||||
high_byte = data[0]
|
||||
indexed_name = high_byte & 0x0F
|
||||
name_len = 4
|
||||
not_indexable = bool(high_byte & 0x10)
|
||||
|
||||
if indexed_name:
|
||||
# Indexed header name.
|
||||
index, consumed = decode_integer(data, name_len)
|
||||
name = self.header_table.get_by_index(index)[0]
|
||||
|
||||
total_consumed = consumed
|
||||
length = 0
|
||||
else:
|
||||
# Literal header name. The first byte was consumed, so we need to
|
||||
# move forward.
|
||||
data = data[1:]
|
||||
|
||||
length, consumed = decode_integer(data, 7)
|
||||
name = data[consumed:consumed + length]
|
||||
if len(name) != length:
|
||||
msg = "Truncated header block"
|
||||
raise HPACKDecodingError(msg)
|
||||
|
||||
if data[0] & 0x80:
|
||||
name = decode_huffman(name)
|
||||
total_consumed = consumed + length + 1 # Since we moved forward 1.
|
||||
|
||||
data = data[consumed + length:]
|
||||
|
||||
# The header value is definitely length-based.
|
||||
length, consumed = decode_integer(data, 7)
|
||||
value = data[consumed:consumed + length]
|
||||
if len(value) != length:
|
||||
msg = "Truncated header block"
|
||||
raise HPACKDecodingError(msg)
|
||||
|
||||
if data[0] & 0x80:
|
||||
value = decode_huffman(value)
|
||||
|
||||
# Updated the total consumed length.
|
||||
total_consumed += length + consumed
|
||||
|
||||
# If we have been told never to index the header field, encode that in
|
||||
# the tuple we use.
|
||||
header: HeaderTuple
|
||||
if not_indexable:
|
||||
header = NeverIndexedHeaderTuple(name, value)
|
||||
else:
|
||||
header = HeaderTuple(name, value)
|
||||
|
||||
# If we've been asked to index this, add it to the header table.
|
||||
if should_index:
|
||||
self.header_table.add(name, value)
|
||||
|
||||
log.debug(
|
||||
"Decoded %s, total consumed %d bytes, indexed %s",
|
||||
header,
|
||||
total_consumed,
|
||||
should_index,
|
||||
)
|
||||
|
||||
return header, total_consumed
|
||||
64
venv/Lib/site-packages/hpack/huffman.py
Normal file
64
venv/Lib/site-packages/hpack/huffman.py
Normal file
@@ -0,0 +1,64 @@
|
||||
"""
|
||||
An implementation of a bitwise prefix tree specially built for decoding
|
||||
Huffman-coded content where we already know the Huffman table.
|
||||
"""
|
||||
from __future__ import annotations
|
||||
|
||||
|
||||
class HuffmanEncoder:
|
||||
"""
|
||||
Encodes a string according to the Huffman encoding table defined in the
|
||||
HPACK specification.
|
||||
"""
|
||||
|
||||
def __init__(self, huffman_code_list: list[int], huffman_code_list_lengths: list[int]) -> None:
|
||||
self.huffman_code_list = huffman_code_list
|
||||
self.huffman_code_list_lengths = huffman_code_list_lengths
|
||||
|
||||
def encode(self, bytes_to_encode: bytes | None) -> bytes:
|
||||
"""
|
||||
Given a string of bytes, encodes them according to the HPACK Huffman
|
||||
specification.
|
||||
"""
|
||||
# If handed the empty string, just immediately return.
|
||||
if not bytes_to_encode:
|
||||
return b""
|
||||
|
||||
final_num = 0
|
||||
final_int_len = 0
|
||||
|
||||
# Turn each byte into its huffman code. These codes aren't necessarily
|
||||
# octet aligned, so keep track of how far through an octet we are. To
|
||||
# handle this cleanly, just use a single giant integer.
|
||||
for byte in bytes_to_encode:
|
||||
bin_int_len = self.huffman_code_list_lengths[byte]
|
||||
bin_int = self.huffman_code_list[byte] & (
|
||||
2 ** (bin_int_len + 1) - 1
|
||||
)
|
||||
final_num <<= bin_int_len
|
||||
final_num |= bin_int
|
||||
final_int_len += bin_int_len
|
||||
|
||||
# Pad out to an octet with ones.
|
||||
bits_to_be_padded = (8 - (final_int_len % 8)) % 8
|
||||
final_num <<= bits_to_be_padded
|
||||
final_num |= (1 << bits_to_be_padded) - 1
|
||||
|
||||
# Convert the number to hex and strip off the leading '0x' and the
|
||||
# trailing 'L', if present.
|
||||
s = hex(final_num)[2:].rstrip("L")
|
||||
|
||||
# If this is odd, prepend a zero.
|
||||
s = "0" + s if len(s) % 2 != 0 else s
|
||||
|
||||
# This number should have twice as many digits as bytes. If not, we're
|
||||
# missing some leading zeroes. Work out how many bytes we want and how
|
||||
# many digits we have, then add the missing zero digits to the front.
|
||||
total_bytes = (final_int_len + bits_to_be_padded) // 8
|
||||
expected_digits = total_bytes * 2
|
||||
|
||||
if len(s) != expected_digits:
|
||||
missing_digits = expected_digits - len(s)
|
||||
s = ("0" * missing_digits) + s
|
||||
|
||||
return bytes.fromhex(s)
|
||||
285
venv/Lib/site-packages/hpack/huffman_constants.py
Normal file
285
venv/Lib/site-packages/hpack/huffman_constants.py
Normal file
@@ -0,0 +1,285 @@
|
||||
"""
|
||||
Defines the constant Huffman table. This takes up an upsetting amount of space,
|
||||
but c'est la vie.
|
||||
"""
|
||||
# flake8: noqa
|
||||
|
||||
REQUEST_CODES = [
|
||||
0x1ff8,
|
||||
0x7fffd8,
|
||||
0xfffffe2,
|
||||
0xfffffe3,
|
||||
0xfffffe4,
|
||||
0xfffffe5,
|
||||
0xfffffe6,
|
||||
0xfffffe7,
|
||||
0xfffffe8,
|
||||
0xffffea,
|
||||
0x3ffffffc,
|
||||
0xfffffe9,
|
||||
0xfffffea,
|
||||
0x3ffffffd,
|
||||
0xfffffeb,
|
||||
0xfffffec,
|
||||
0xfffffed,
|
||||
0xfffffee,
|
||||
0xfffffef,
|
||||
0xffffff0,
|
||||
0xffffff1,
|
||||
0xffffff2,
|
||||
0x3ffffffe,
|
||||
0xffffff3,
|
||||
0xffffff4,
|
||||
0xffffff5,
|
||||
0xffffff6,
|
||||
0xffffff7,
|
||||
0xffffff8,
|
||||
0xffffff9,
|
||||
0xffffffa,
|
||||
0xffffffb,
|
||||
0x14,
|
||||
0x3f8,
|
||||
0x3f9,
|
||||
0xffa,
|
||||
0x1ff9,
|
||||
0x15,
|
||||
0xf8,
|
||||
0x7fa,
|
||||
0x3fa,
|
||||
0x3fb,
|
||||
0xf9,
|
||||
0x7fb,
|
||||
0xfa,
|
||||
0x16,
|
||||
0x17,
|
||||
0x18,
|
||||
0x0,
|
||||
0x1,
|
||||
0x2,
|
||||
0x19,
|
||||
0x1a,
|
||||
0x1b,
|
||||
0x1c,
|
||||
0x1d,
|
||||
0x1e,
|
||||
0x1f,
|
||||
0x5c,
|
||||
0xfb,
|
||||
0x7ffc,
|
||||
0x20,
|
||||
0xffb,
|
||||
0x3fc,
|
||||
0x1ffa,
|
||||
0x21,
|
||||
0x5d,
|
||||
0x5e,
|
||||
0x5f,
|
||||
0x60,
|
||||
0x61,
|
||||
0x62,
|
||||
0x63,
|
||||
0x64,
|
||||
0x65,
|
||||
0x66,
|
||||
0x67,
|
||||
0x68,
|
||||
0x69,
|
||||
0x6a,
|
||||
0x6b,
|
||||
0x6c,
|
||||
0x6d,
|
||||
0x6e,
|
||||
0x6f,
|
||||
0x70,
|
||||
0x71,
|
||||
0x72,
|
||||
0xfc,
|
||||
0x73,
|
||||
0xfd,
|
||||
0x1ffb,
|
||||
0x7fff0,
|
||||
0x1ffc,
|
||||
0x3ffc,
|
||||
0x22,
|
||||
0x7ffd,
|
||||
0x3,
|
||||
0x23,
|
||||
0x4,
|
||||
0x24,
|
||||
0x5,
|
||||
0x25,
|
||||
0x26,
|
||||
0x27,
|
||||
0x6,
|
||||
0x74,
|
||||
0x75,
|
||||
0x28,
|
||||
0x29,
|
||||
0x2a,
|
||||
0x7,
|
||||
0x2b,
|
||||
0x76,
|
||||
0x2c,
|
||||
0x8,
|
||||
0x9,
|
||||
0x2d,
|
||||
0x77,
|
||||
0x78,
|
||||
0x79,
|
||||
0x7a,
|
||||
0x7b,
|
||||
0x7ffe,
|
||||
0x7fc,
|
||||
0x3ffd,
|
||||
0x1ffd,
|
||||
0xffffffc,
|
||||
0xfffe6,
|
||||
0x3fffd2,
|
||||
0xfffe7,
|
||||
0xfffe8,
|
||||
0x3fffd3,
|
||||
0x3fffd4,
|
||||
0x3fffd5,
|
||||
0x7fffd9,
|
||||
0x3fffd6,
|
||||
0x7fffda,
|
||||
0x7fffdb,
|
||||
0x7fffdc,
|
||||
0x7fffdd,
|
||||
0x7fffde,
|
||||
0xffffeb,
|
||||
0x7fffdf,
|
||||
0xffffec,
|
||||
0xffffed,
|
||||
0x3fffd7,
|
||||
0x7fffe0,
|
||||
0xffffee,
|
||||
0x7fffe1,
|
||||
0x7fffe2,
|
||||
0x7fffe3,
|
||||
0x7fffe4,
|
||||
0x1fffdc,
|
||||
0x3fffd8,
|
||||
0x7fffe5,
|
||||
0x3fffd9,
|
||||
0x7fffe6,
|
||||
0x7fffe7,
|
||||
0xffffef,
|
||||
0x3fffda,
|
||||
0x1fffdd,
|
||||
0xfffe9,
|
||||
0x3fffdb,
|
||||
0x3fffdc,
|
||||
0x7fffe8,
|
||||
0x7fffe9,
|
||||
0x1fffde,
|
||||
0x7fffea,
|
||||
0x3fffdd,
|
||||
0x3fffde,
|
||||
0xfffff0,
|
||||
0x1fffdf,
|
||||
0x3fffdf,
|
||||
0x7fffeb,
|
||||
0x7fffec,
|
||||
0x1fffe0,
|
||||
0x1fffe1,
|
||||
0x3fffe0,
|
||||
0x1fffe2,
|
||||
0x7fffed,
|
||||
0x3fffe1,
|
||||
0x7fffee,
|
||||
0x7fffef,
|
||||
0xfffea,
|
||||
0x3fffe2,
|
||||
0x3fffe3,
|
||||
0x3fffe4,
|
||||
0x7ffff0,
|
||||
0x3fffe5,
|
||||
0x3fffe6,
|
||||
0x7ffff1,
|
||||
0x3ffffe0,
|
||||
0x3ffffe1,
|
||||
0xfffeb,
|
||||
0x7fff1,
|
||||
0x3fffe7,
|
||||
0x7ffff2,
|
||||
0x3fffe8,
|
||||
0x1ffffec,
|
||||
0x3ffffe2,
|
||||
0x3ffffe3,
|
||||
0x3ffffe4,
|
||||
0x7ffffde,
|
||||
0x7ffffdf,
|
||||
0x3ffffe5,
|
||||
0xfffff1,
|
||||
0x1ffffed,
|
||||
0x7fff2,
|
||||
0x1fffe3,
|
||||
0x3ffffe6,
|
||||
0x7ffffe0,
|
||||
0x7ffffe1,
|
||||
0x3ffffe7,
|
||||
0x7ffffe2,
|
||||
0xfffff2,
|
||||
0x1fffe4,
|
||||
0x1fffe5,
|
||||
0x3ffffe8,
|
||||
0x3ffffe9,
|
||||
0xffffffd,
|
||||
0x7ffffe3,
|
||||
0x7ffffe4,
|
||||
0x7ffffe5,
|
||||
0xfffec,
|
||||
0xfffff3,
|
||||
0xfffed,
|
||||
0x1fffe6,
|
||||
0x3fffe9,
|
||||
0x1fffe7,
|
||||
0x1fffe8,
|
||||
0x7ffff3,
|
||||
0x3fffea,
|
||||
0x3fffeb,
|
||||
0x1ffffee,
|
||||
0x1ffffef,
|
||||
0xfffff4,
|
||||
0xfffff5,
|
||||
0x3ffffea,
|
||||
0x7ffff4,
|
||||
0x3ffffeb,
|
||||
0x7ffffe6,
|
||||
0x3ffffec,
|
||||
0x3ffffed,
|
||||
0x7ffffe7,
|
||||
0x7ffffe8,
|
||||
0x7ffffe9,
|
||||
0x7ffffea,
|
||||
0x7ffffeb,
|
||||
0xffffffe,
|
||||
0x7ffffec,
|
||||
0x7ffffed,
|
||||
0x7ffffee,
|
||||
0x7ffffef,
|
||||
0x7fffff0,
|
||||
0x3ffffee,
|
||||
0x3fffffff,
|
||||
]
|
||||
|
||||
REQUEST_CODES_LENGTH = [
|
||||
13, 23, 28, 28, 28, 28, 28, 28, 28, 24, 30, 28, 28, 30, 28, 28,
|
||||
28, 28, 28, 28, 28, 28, 30, 28, 28, 28, 28, 28, 28, 28, 28, 28,
|
||||
6, 10, 10, 12, 13, 6, 8, 11, 10, 10, 8, 11, 8, 6, 6, 6,
|
||||
5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 7, 8, 15, 6, 12, 10,
|
||||
13, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
|
||||
7, 7, 7, 7, 7, 7, 7, 7, 8, 7, 8, 13, 19, 13, 14, 6,
|
||||
15, 5, 6, 5, 6, 5, 6, 6, 6, 5, 7, 7, 6, 6, 6, 5,
|
||||
6, 7, 6, 5, 5, 6, 7, 7, 7, 7, 7, 15, 11, 14, 13, 28,
|
||||
20, 22, 20, 20, 22, 22, 22, 23, 22, 23, 23, 23, 23, 23, 24, 23,
|
||||
24, 24, 22, 23, 24, 23, 23, 23, 23, 21, 22, 23, 22, 23, 23, 24,
|
||||
22, 21, 20, 22, 22, 23, 23, 21, 23, 22, 22, 24, 21, 22, 23, 23,
|
||||
21, 21, 22, 21, 23, 22, 23, 23, 20, 22, 22, 22, 23, 22, 22, 23,
|
||||
26, 26, 20, 19, 22, 23, 22, 25, 26, 26, 26, 27, 27, 26, 24, 25,
|
||||
19, 21, 26, 27, 27, 26, 27, 24, 21, 21, 26, 26, 28, 27, 27, 27,
|
||||
20, 24, 20, 21, 22, 21, 21, 23, 22, 22, 25, 25, 24, 24, 26, 23,
|
||||
26, 27, 26, 26, 27, 27, 27, 27, 27, 28, 27, 27, 27, 27, 27, 26,
|
||||
30,
|
||||
]
|
||||
4741
venv/Lib/site-packages/hpack/huffman_table.py
Normal file
4741
venv/Lib/site-packages/hpack/huffman_table.py
Normal file
File diff suppressed because it is too large
Load Diff
0
venv/Lib/site-packages/hpack/py.typed
Normal file
0
venv/Lib/site-packages/hpack/py.typed
Normal file
50
venv/Lib/site-packages/hpack/struct.py
Normal file
50
venv/Lib/site-packages/hpack/struct.py
Normal file
@@ -0,0 +1,50 @@
|
||||
"""
|
||||
Contains structures for representing header fields with associated metadata.
|
||||
"""
|
||||
from __future__ import annotations
|
||||
|
||||
from typing import TYPE_CHECKING, Any
|
||||
|
||||
if TYPE_CHECKING:
|
||||
from typing_extensions import Self, TypeAlias # pragma: no cover
|
||||
|
||||
|
||||
class HeaderTuple(tuple[bytes, bytes]):
|
||||
"""
|
||||
A data structure that stores a single header field.
|
||||
|
||||
HTTP headers can be thought of as tuples of ``(field name, field value)``.
|
||||
A single header block is a sequence of such tuples.
|
||||
|
||||
In HTTP/2, however, certain bits of additional information are required for
|
||||
compressing these headers: in particular, whether the header field can be
|
||||
safely added to the HPACK compression context.
|
||||
|
||||
This class stores a header that can be added to the compression context. In
|
||||
all other ways it behaves exactly like a tuple.
|
||||
"""
|
||||
|
||||
__slots__ = ()
|
||||
|
||||
indexable = True
|
||||
|
||||
def __new__(cls, *args: Any) -> Self:
|
||||
return tuple.__new__(cls, args)
|
||||
|
||||
|
||||
class NeverIndexedHeaderTuple(HeaderTuple):
|
||||
"""
|
||||
A data structure that stores a single header field that cannot be added to
|
||||
a HTTP/2 header compression context.
|
||||
"""
|
||||
|
||||
__slots__ = ()
|
||||
|
||||
indexable = False
|
||||
|
||||
def __new__(cls, *args: Any) -> Self:
|
||||
return tuple.__new__(cls, args)
|
||||
|
||||
|
||||
Header: TypeAlias = "HeaderTuple | NeverIndexedHeaderTuple | tuple[bytes, bytes]"
|
||||
HeaderWeaklyTyped: TypeAlias = "HeaderTuple | NeverIndexedHeaderTuple | tuple[bytes | str, bytes | str]"
|
||||
237
venv/Lib/site-packages/hpack/table.py
Normal file
237
venv/Lib/site-packages/hpack/table.py
Normal file
@@ -0,0 +1,237 @@
|
||||
# flake8: noqa
|
||||
from collections import deque
|
||||
import logging
|
||||
from typing import Optional
|
||||
|
||||
from .exceptions import InvalidTableIndex
|
||||
|
||||
log = logging.getLogger(__name__)
|
||||
|
||||
|
||||
def table_entry_size(name: bytes, value: bytes) -> int:
|
||||
"""
|
||||
Calculates the size of a single entry
|
||||
|
||||
This size is mostly irrelevant to us and defined
|
||||
specifically to accommodate memory management for
|
||||
lower level implementations. The 32 extra bytes are
|
||||
considered the "maximum" overhead that would be
|
||||
required to represent each entry in the table.
|
||||
|
||||
See RFC7541 Section 4.1
|
||||
"""
|
||||
return 32 + len(name) + len(value)
|
||||
|
||||
|
||||
class HeaderTable:
|
||||
"""
|
||||
Implements the combined static and dynamic header table
|
||||
|
||||
The name and value arguments for all the functions
|
||||
should ONLY be byte strings (b'') however this is not
|
||||
strictly enforced in the interface.
|
||||
|
||||
See RFC7541 Section 2.3
|
||||
"""
|
||||
#: Default maximum size of the dynamic table. See
|
||||
#: RFC7540 Section 6.5.2.
|
||||
DEFAULT_SIZE = 4096
|
||||
|
||||
#: Constant list of static headers. See RFC7541 Section
|
||||
#: 2.3.1 and Appendix A
|
||||
STATIC_TABLE = (
|
||||
(b':authority' , b'' ), # noqa
|
||||
(b':method' , b'GET' ), # noqa
|
||||
(b':method' , b'POST' ), # noqa
|
||||
(b':path' , b'/' ), # noqa
|
||||
(b':path' , b'/index.html' ), # noqa
|
||||
(b':scheme' , b'http' ), # noqa
|
||||
(b':scheme' , b'https' ), # noqa
|
||||
(b':status' , b'200' ), # noqa
|
||||
(b':status' , b'204' ), # noqa
|
||||
(b':status' , b'206' ), # noqa
|
||||
(b':status' , b'304' ), # noqa
|
||||
(b':status' , b'400' ), # noqa
|
||||
(b':status' , b'404' ), # noqa
|
||||
(b':status' , b'500' ), # noqa
|
||||
(b'accept-charset' , b'' ), # noqa
|
||||
(b'accept-encoding' , b'gzip, deflate'), # noqa
|
||||
(b'accept-language' , b'' ), # noqa
|
||||
(b'accept-ranges' , b'' ), # noqa
|
||||
(b'accept' , b'' ), # noqa
|
||||
(b'access-control-allow-origin' , b'' ), # noqa
|
||||
(b'age' , b'' ), # noqa
|
||||
(b'allow' , b'' ), # noqa
|
||||
(b'authorization' , b'' ), # noqa
|
||||
(b'cache-control' , b'' ), # noqa
|
||||
(b'content-disposition' , b'' ), # noqa
|
||||
(b'content-encoding' , b'' ), # noqa
|
||||
(b'content-language' , b'' ), # noqa
|
||||
(b'content-length' , b'' ), # noqa
|
||||
(b'content-location' , b'' ), # noqa
|
||||
(b'content-range' , b'' ), # noqa
|
||||
(b'content-type' , b'' ), # noqa
|
||||
(b'cookie' , b'' ), # noqa
|
||||
(b'date' , b'' ), # noqa
|
||||
(b'etag' , b'' ), # noqa
|
||||
(b'expect' , b'' ), # noqa
|
||||
(b'expires' , b'' ), # noqa
|
||||
(b'from' , b'' ), # noqa
|
||||
(b'host' , b'' ), # noqa
|
||||
(b'if-match' , b'' ), # noqa
|
||||
(b'if-modified-since' , b'' ), # noqa
|
||||
(b'if-none-match' , b'' ), # noqa
|
||||
(b'if-range' , b'' ), # noqa
|
||||
(b'if-unmodified-since' , b'' ), # noqa
|
||||
(b'last-modified' , b'' ), # noqa
|
||||
(b'link' , b'' ), # noqa
|
||||
(b'location' , b'' ), # noqa
|
||||
(b'max-forwards' , b'' ), # noqa
|
||||
(b'proxy-authenticate' , b'' ), # noqa
|
||||
(b'proxy-authorization' , b'' ), # noqa
|
||||
(b'range' , b'' ), # noqa
|
||||
(b'referer' , b'' ), # noqa
|
||||
(b'refresh' , b'' ), # noqa
|
||||
(b'retry-after' , b'' ), # noqa
|
||||
(b'server' , b'' ), # noqa
|
||||
(b'set-cookie' , b'' ), # noqa
|
||||
(b'strict-transport-security' , b'' ), # noqa
|
||||
(b'transfer-encoding' , b'' ), # noqa
|
||||
(b'user-agent' , b'' ), # noqa
|
||||
(b'vary' , b'' ), # noqa
|
||||
(b'via' , b'' ), # noqa
|
||||
(b'www-authenticate' , b'' ), # noqa
|
||||
) # noqa
|
||||
|
||||
STATIC_TABLE_LENGTH = len(STATIC_TABLE)
|
||||
|
||||
STATIC_TABLE_MAPPING: dict[bytes, tuple[int, dict[bytes, int]]]
|
||||
|
||||
def __init__(self) -> None:
|
||||
self._maxsize = HeaderTable.DEFAULT_SIZE
|
||||
self._current_size = 0
|
||||
self.resized = False
|
||||
self.dynamic_entries: deque[tuple[bytes, bytes]] = deque()
|
||||
|
||||
def get_by_index(self, index: int) -> tuple[bytes, bytes]:
|
||||
"""
|
||||
Returns the entry specified by index
|
||||
|
||||
Note that the table is 1-based ie an index of 0 is
|
||||
invalid. This is due to the fact that a zero value
|
||||
index signals that a completely unindexed header
|
||||
follows.
|
||||
|
||||
The entry will either be from the static table or
|
||||
the dynamic table depending on the value of index.
|
||||
"""
|
||||
original_index = index
|
||||
index -= 1
|
||||
if 0 <= index:
|
||||
if index < HeaderTable.STATIC_TABLE_LENGTH:
|
||||
return HeaderTable.STATIC_TABLE[index]
|
||||
|
||||
index -= HeaderTable.STATIC_TABLE_LENGTH
|
||||
if index < len(self.dynamic_entries):
|
||||
return self.dynamic_entries[index]
|
||||
|
||||
raise InvalidTableIndex("Invalid table index %d" % original_index)
|
||||
|
||||
def __repr__(self) -> str:
|
||||
return "HeaderTable(%d, %s, %r)" % (
|
||||
self._maxsize,
|
||||
self.resized,
|
||||
self.dynamic_entries
|
||||
)
|
||||
|
||||
def add(self, name: bytes, value: bytes) -> None:
|
||||
"""
|
||||
Adds a new entry to the table
|
||||
|
||||
We reduce the table size if the entry will make the
|
||||
table size greater than maxsize.
|
||||
"""
|
||||
# We just clear the table if the entry is too big
|
||||
size = table_entry_size(name, value)
|
||||
if size > self._maxsize:
|
||||
self.dynamic_entries.clear()
|
||||
self._current_size = 0
|
||||
else:
|
||||
# Add new entry
|
||||
self.dynamic_entries.appendleft((name, value))
|
||||
self._current_size += size
|
||||
self._shrink()
|
||||
|
||||
def search(self, name: bytes, value: bytes) -> Optional[tuple[int, bytes, Optional[bytes]]]:
|
||||
"""
|
||||
Searches the table for the entry specified by name
|
||||
and value
|
||||
|
||||
Returns one of the following:
|
||||
- ``None``, no match at all
|
||||
- ``(index, name, None)`` for partial matches on name only.
|
||||
- ``(index, name, value)`` for perfect matches.
|
||||
"""
|
||||
partial = None
|
||||
|
||||
header_name_search_result = HeaderTable.STATIC_TABLE_MAPPING.get(name)
|
||||
if header_name_search_result:
|
||||
index = header_name_search_result[1].get(value)
|
||||
if index is not None:
|
||||
return index, name, value
|
||||
else:
|
||||
partial = (header_name_search_result[0], name, None)
|
||||
|
||||
offset = HeaderTable.STATIC_TABLE_LENGTH + 1
|
||||
for (i, (n, v)) in enumerate(self.dynamic_entries):
|
||||
if n == name:
|
||||
if v == value:
|
||||
return i + offset, n, v
|
||||
elif partial is None:
|
||||
partial = (i + offset, n, None)
|
||||
return partial
|
||||
|
||||
@property
|
||||
def maxsize(self) -> int:
|
||||
return self._maxsize
|
||||
|
||||
@maxsize.setter
|
||||
def maxsize(self, newmax: int) -> None:
|
||||
newmax = int(newmax)
|
||||
log.debug("Resizing header table to %d from %d", newmax, self._maxsize)
|
||||
oldmax = self._maxsize
|
||||
self._maxsize = newmax
|
||||
self.resized = (newmax != oldmax)
|
||||
if newmax <= 0:
|
||||
self.dynamic_entries.clear()
|
||||
self._current_size = 0
|
||||
elif oldmax > newmax:
|
||||
self._shrink()
|
||||
|
||||
def _shrink(self) -> None:
|
||||
"""
|
||||
Shrinks the dynamic table to be at or below maxsize
|
||||
"""
|
||||
cursize = self._current_size
|
||||
while cursize > self._maxsize:
|
||||
name, value = self.dynamic_entries.pop()
|
||||
cursize -= table_entry_size(name, value)
|
||||
log.debug("Evicting %s: %s from the header table", name, value)
|
||||
self._current_size = cursize
|
||||
|
||||
|
||||
def _build_static_table_mapping() -> dict[bytes, tuple[int, dict[bytes, int]]]:
|
||||
"""
|
||||
Build static table mapping from header name to tuple with next structure:
|
||||
(<minimal index of header>, <mapping from header value to it index>).
|
||||
|
||||
static_table_mapping used for hash searching.
|
||||
"""
|
||||
static_table_mapping: dict[bytes, tuple[int, dict[bytes, int]]] = {}
|
||||
for index, (name, value) in enumerate(HeaderTable.STATIC_TABLE, 1):
|
||||
header_name_search_result = static_table_mapping.setdefault(name, (index, {}))
|
||||
header_name_search_result[1][value] = index
|
||||
return static_table_mapping
|
||||
|
||||
|
||||
HeaderTable.STATIC_TABLE_MAPPING = _build_static_table_mapping()
|
||||
Reference in New Issue
Block a user