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Diffstat (limited to 'frozen_deps/Cryptodome/Hash/BLAKE2b.py')
| -rw-r--r-- | frozen_deps/Cryptodome/Hash/BLAKE2b.py | 247 |
1 files changed, 247 insertions, 0 deletions
diff --git a/frozen_deps/Cryptodome/Hash/BLAKE2b.py b/frozen_deps/Cryptodome/Hash/BLAKE2b.py new file mode 100644 index 0000000..d7e968f --- /dev/null +++ b/frozen_deps/Cryptodome/Hash/BLAKE2b.py @@ -0,0 +1,247 @@ +# =================================================================== +# +# Copyright (c) 2014, Legrandin <helderijs@gmail.com> +# All rights reserved. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions +# are met: +# +# 1. Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# 2. Redistributions in binary form must reproduce the above copyright +# notice, this list of conditions and the following disclaimer in +# the documentation and/or other materials provided with the +# distribution. +# +# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS +# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE +# COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, +# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, +# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; +# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER +# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN +# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +# POSSIBILITY OF SUCH DAMAGE. +# =================================================================== + +from binascii import unhexlify + +from Cryptodome.Util.py3compat import bord, tobytes + +from Cryptodome.Random import get_random_bytes +from Cryptodome.Util._raw_api import (load_pycryptodome_raw_lib, + VoidPointer, SmartPointer, + create_string_buffer, + get_raw_buffer, c_size_t, + c_uint8_ptr) + +_raw_blake2b_lib = load_pycryptodome_raw_lib("Cryptodome.Hash._BLAKE2b", + """ + int blake2b_init(void **state, + const uint8_t *key, + size_t key_size, + size_t digest_size); + int blake2b_destroy(void *state); + int blake2b_update(void *state, + const uint8_t *buf, + size_t len); + int blake2b_digest(const void *state, + uint8_t digest[64]); + int blake2b_copy(const void *src, void *dst); + """) + + +class BLAKE2b_Hash(object): + """A BLAKE2b hash object. + Do not instantiate directly. Use the :func:`new` function. + + :ivar oid: ASN.1 Object ID + :vartype oid: string + + :ivar block_size: the size in bytes of the internal message block, + input to the compression function + :vartype block_size: integer + + :ivar digest_size: the size in bytes of the resulting hash + :vartype digest_size: integer + """ + + # The internal block size of the hash algorithm in bytes. + block_size = 64 + + def __init__(self, data, key, digest_bytes, update_after_digest): + + # The size of the resulting hash in bytes. + self.digest_size = digest_bytes + + self._update_after_digest = update_after_digest + self._digest_done = False + + # See https://tools.ietf.org/html/rfc7693 + if digest_bytes in (20, 32, 48, 64) and not key: + self.oid = "1.3.6.1.4.1.1722.12.2.1." + str(digest_bytes) + + state = VoidPointer() + result = _raw_blake2b_lib.blake2b_init(state.address_of(), + c_uint8_ptr(key), + c_size_t(len(key)), + c_size_t(digest_bytes) + ) + if result: + raise ValueError("Error %d while instantiating BLAKE2b" % result) + self._state = SmartPointer(state.get(), + _raw_blake2b_lib.blake2b_destroy) + if data: + self.update(data) + + + def update(self, data): + """Continue hashing of a message by consuming the next chunk of data. + + Args: + data (bytes/bytearray/memoryview): The next chunk of the message being hashed. + """ + + if self._digest_done and not self._update_after_digest: + raise TypeError("You can only call 'digest' or 'hexdigest' on this object") + + result = _raw_blake2b_lib.blake2b_update(self._state.get(), + c_uint8_ptr(data), + c_size_t(len(data))) + if result: + raise ValueError("Error %d while hashing BLAKE2b data" % result) + return self + + + def digest(self): + """Return the **binary** (non-printable) digest of the message that has been hashed so far. + + :return: The hash digest, computed over the data processed so far. + Binary form. + :rtype: byte string + """ + + bfr = create_string_buffer(64) + result = _raw_blake2b_lib.blake2b_digest(self._state.get(), + bfr) + if result: + raise ValueError("Error %d while creating BLAKE2b digest" % result) + + self._digest_done = True + + return get_raw_buffer(bfr)[:self.digest_size] + + + def hexdigest(self): + """Return the **printable** digest of the message that has been hashed so far. + + :return: The hash digest, computed over the data processed so far. + Hexadecimal encoded. + :rtype: string + """ + + return "".join(["%02x" % bord(x) for x in tuple(self.digest())]) + + + def verify(self, mac_tag): + """Verify that a given **binary** MAC (computed by another party) + is valid. + + Args: + mac_tag (bytes/bytearray/memoryview): the expected MAC of the message. + + Raises: + ValueError: if the MAC does not match. It means that the message + has been tampered with or that the MAC key is incorrect. + """ + + secret = get_random_bytes(16) + + mac1 = new(digest_bits=160, key=secret, data=mac_tag) + mac2 = new(digest_bits=160, key=secret, data=self.digest()) + + if mac1.digest() != mac2.digest(): + raise ValueError("MAC check failed") + + + def hexverify(self, hex_mac_tag): + """Verify that a given **printable** MAC (computed by another party) + is valid. + + Args: + hex_mac_tag (string): the expected MAC of the message, as a hexadecimal string. + + Raises: + ValueError: if the MAC does not match. It means that the message + has been tampered with or that the MAC key is incorrect. + """ + + self.verify(unhexlify(tobytes(hex_mac_tag))) + + + def new(self, **kwargs): + """Return a new instance of a BLAKE2b hash object. + See :func:`new`. + """ + + if "digest_bytes" not in kwargs and "digest_bits" not in kwargs: + kwargs["digest_bytes"] = self.digest_size + + return new(**kwargs) + + +def new(**kwargs): + """Create a new hash object. + + Args: + data (bytes/bytearray/memoryview): + Optional. The very first chunk of the message to hash. + It is equivalent to an early call to :meth:`BLAKE2b_Hash.update`. + digest_bytes (integer): + Optional. The size of the digest, in bytes (1 to 64). Default is 64. + digest_bits (integer): + Optional and alternative to ``digest_bytes``. + The size of the digest, in bits (8 to 512, in steps of 8). + Default is 512. + key (bytes/bytearray/memoryview): + Optional. The key to use to compute the MAC (1 to 64 bytes). + If not specified, no key will be used. + update_after_digest (boolean): + Optional. By default, a hash object cannot be updated anymore after + the digest is computed. When this flag is ``True``, such check + is no longer enforced. + + Returns: + A :class:`BLAKE2b_Hash` hash object + """ + + data = kwargs.pop("data", None) + update_after_digest = kwargs.pop("update_after_digest", False) + + digest_bytes = kwargs.pop("digest_bytes", None) + digest_bits = kwargs.pop("digest_bits", None) + if None not in (digest_bytes, digest_bits): + raise TypeError("Only one digest parameter must be provided") + if (None, None) == (digest_bytes, digest_bits): + digest_bytes = 64 + if digest_bytes is not None: + if not (1 <= digest_bytes <= 64): + raise ValueError("'digest_bytes' not in range 1..64") + else: + if not (8 <= digest_bits <= 512) or (digest_bits % 8): + raise ValueError("'digest_bytes' not in range 8..512, " + "with steps of 8") + digest_bytes = digest_bits // 8 + + key = kwargs.pop("key", b"") + if len(key) > 64: + raise ValueError("BLAKE2s key cannot exceed 64 bytes") + + if kwargs: + raise TypeError("Unknown parameters: " + str(kwargs)) + + return BLAKE2b_Hash(data, key, digest_bytes, update_after_digest) |