updates

Backend/venv/lib/python3.12/site-packages/cryptography/hazmat/primitives/padding.py

@@ -5,19 +5,19 @@
 from __future__ import annotations
 
 import abc
-import typing
 
 from cryptography import utils
-from cryptography.exceptions import AlreadyFinalized
 from cryptography.hazmat.bindings._rust import (
-    check_ansix923_padding,
-    check_pkcs7_padding,
+    ANSIX923PaddingContext,
+    ANSIX923UnpaddingContext,
+    PKCS7PaddingContext,
+    PKCS7UnpaddingContext,
 )
 
 
 class PaddingContext(metaclass=abc.ABCMeta):
     @abc.abstractmethod
-    def update(self, data: bytes) -> bytes:
+    def update(self, data: utils.Buffer) -> bytes:
         """
         Pads the provided bytes and returns any available data as bytes.
         """
@@ -37,131 +37,20 @@ def _byte_padding_check(block_size: int) -> None:
         raise ValueError("block_size must be a multiple of 8.")
 
 
-def _byte_padding_update(
-    buffer_: typing.Optional[bytes], data: bytes, block_size: int
-) -> typing.Tuple[bytes, bytes]:
-    if buffer_ is None:
-        raise AlreadyFinalized("Context was already finalized.")
-
-    utils._check_byteslike("data", data)
-
-    buffer_ += bytes(data)
-
-    finished_blocks = len(buffer_) // (block_size // 8)
-
-    result = buffer_[: finished_blocks * (block_size // 8)]
-    buffer_ = buffer_[finished_blocks * (block_size // 8) :]
-
-    return buffer_, result
-
-
-def _byte_padding_pad(
-    buffer_: typing.Optional[bytes],
-    block_size: int,
-    paddingfn: typing.Callable[[int], bytes],
-) -> bytes:
-    if buffer_ is None:
-        raise AlreadyFinalized("Context was already finalized.")
-
-    pad_size = block_size // 8 - len(buffer_)
-    return buffer_ + paddingfn(pad_size)
-
-
-def _byte_unpadding_update(
-    buffer_: typing.Optional[bytes], data: bytes, block_size: int
-) -> typing.Tuple[bytes, bytes]:
-    if buffer_ is None:
-        raise AlreadyFinalized("Context was already finalized.")
-
-    utils._check_byteslike("data", data)
-
-    buffer_ += bytes(data)
-
-    finished_blocks = max(len(buffer_) // (block_size // 8) - 1, 0)
-
-    result = buffer_[: finished_blocks * (block_size // 8)]
-    buffer_ = buffer_[finished_blocks * (block_size // 8) :]
-
-    return buffer_, result
-
-
-def _byte_unpadding_check(
-    buffer_: typing.Optional[bytes],
-    block_size: int,
-    checkfn: typing.Callable[[bytes], int],
-) -> bytes:
-    if buffer_ is None:
-        raise AlreadyFinalized("Context was already finalized.")
-
-    if len(buffer_) != block_size // 8:
-        raise ValueError("Invalid padding bytes.")
-
-    valid = checkfn(buffer_)
-
-    if not valid:
-        raise ValueError("Invalid padding bytes.")
-
-    pad_size = buffer_[-1]
-    return buffer_[:-pad_size]
-
-
 class PKCS7:
     def __init__(self, block_size: int):
         _byte_padding_check(block_size)
         self.block_size = block_size
 
     def padder(self) -> PaddingContext:
-        return _PKCS7PaddingContext(self.block_size)
+        return PKCS7PaddingContext(self.block_size)
 
     def unpadder(self) -> PaddingContext:
-        return _PKCS7UnpaddingContext(self.block_size)
+        return PKCS7UnpaddingContext(self.block_size)
 
 
-class _PKCS7PaddingContext(PaddingContext):
-    _buffer: typing.Optional[bytes]
-
-    def __init__(self, block_size: int):
-        self.block_size = block_size
-        # TODO: more copies than necessary, we should use zero-buffer (#193)
-        self._buffer = b""
-
-    def update(self, data: bytes) -> bytes:
-        self._buffer, result = _byte_padding_update(
-            self._buffer, data, self.block_size
-        )
-        return result
-
-    def _padding(self, size: int) -> bytes:
-        return bytes([size]) * size
-
-    def finalize(self) -> bytes:
-        result = _byte_padding_pad(
-            self._buffer, self.block_size, self._padding
-        )
-        self._buffer = None
-        return result
-
-
-class _PKCS7UnpaddingContext(PaddingContext):
-    _buffer: typing.Optional[bytes]
-
-    def __init__(self, block_size: int):
-        self.block_size = block_size
-        # TODO: more copies than necessary, we should use zero-buffer (#193)
-        self._buffer = b""
-
-    def update(self, data: bytes) -> bytes:
-        self._buffer, result = _byte_unpadding_update(
-            self._buffer, data, self.block_size
-        )
-        return result
-
-    def finalize(self) -> bytes:
-        result = _byte_unpadding_check(
-            self._buffer, self.block_size, check_pkcs7_padding
-        )
-        self._buffer = None
-        return result
+PaddingContext.register(PKCS7PaddingContext)
+PaddingContext.register(PKCS7UnpaddingContext)
 
 
 class ANSIX923:
@@ -170,56 +59,11 @@ class ANSIX923:
         self.block_size = block_size
 
     def padder(self) -> PaddingContext:
-        return _ANSIX923PaddingContext(self.block_size)
+        return ANSIX923PaddingContext(self.block_size)
 
     def unpadder(self) -> PaddingContext:
-        return _ANSIX923UnpaddingContext(self.block_size)
+        return ANSIX923UnpaddingContext(self.block_size)
 
 
-class _ANSIX923PaddingContext(PaddingContext):
-    _buffer: typing.Optional[bytes]
-
-    def __init__(self, block_size: int):
-        self.block_size = block_size
-        # TODO: more copies than necessary, we should use zero-buffer (#193)
-        self._buffer = b""
-
-    def update(self, data: bytes) -> bytes:
-        self._buffer, result = _byte_padding_update(
-            self._buffer, data, self.block_size
-        )
-        return result
-
-    def _padding(self, size: int) -> bytes:
-        return bytes([0]) * (size - 1) + bytes([size])
-
-    def finalize(self) -> bytes:
-        result = _byte_padding_pad(
-            self._buffer, self.block_size, self._padding
-        )
-        self._buffer = None
-        return result
-
-
-class _ANSIX923UnpaddingContext(PaddingContext):
-    _buffer: typing.Optional[bytes]
-
-    def __init__(self, block_size: int):
-        self.block_size = block_size
-        # TODO: more copies than necessary, we should use zero-buffer (#193)
-        self._buffer = b""
-
-    def update(self, data: bytes) -> bytes:
-        self._buffer, result = _byte_unpadding_update(
-            self._buffer, data, self.block_size
-        )
-        return result
-
-    def finalize(self) -> bytes:
-        result = _byte_unpadding_check(
-            self._buffer,
-            self.block_size,
-            check_ansix923_padding,
-        )
-        self._buffer = None
-        return result
+PaddingContext.register(ANSIX923PaddingContext)
+PaddingContext.register(ANSIX923UnpaddingContext)