Add google-endpoints to third_party/.

third_party/google-endpoints/Crypto/Hash/SHA256.py

+# -*- coding: utf-8 -*-
+#
+# ===================================================================
+# The contents of this file are dedicated to the public domain.  To
+# the extent that dedication to the public domain is not available,
+# everyone is granted a worldwide, perpetual, royalty-free,
+# non-exclusive license to exercise all rights associated with the
+# contents of this file for any purpose whatsoever.
+# No rights are reserved.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+# BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+# ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+# ===================================================================
+
+"""SHA-256 cryptographic hash algorithm.
+
+SHA-256 belongs to the SHA-2_ family of cryptographic hashes.
+It produces the 256 bit digest of a message.
+
+    >>> from Crypto.Hash import SHA256
+    >>>
+    >>> h = SHA256.new()
+    >>> h.update(b'Hello')
+    >>> print h.hexdigest()
+
+*SHA* stands for Secure Hash Algorithm.
+
+.. _SHA-2: http://csrc.nist.gov/publications/fips/fips180-2/fips180-2.pdf
+"""
+
+_revision__ = "$Id$"
+
+__all__ = ['new', 'digest_size', 'SHA256Hash' ]
+
+from Crypto.Util.py3compat import *
+from Crypto.Hash.hashalgo import HashAlgo
+
+try:
+    import hashlib
+    hashFactory = hashlib.sha256
+
+except ImportError:
+    from Crypto.Hash import _SHA256
+    hashFactory = _SHA256
+
+class SHA256Hash(HashAlgo):
+    """Class that implements a SHA-256 hash
+    
+    :undocumented: block_size
+    """
+
+    #: ASN.1 Object identifier (OID)::
+    #:
+    #:  id-sha256    OBJECT IDENTIFIER ::= {
+    #:      joint-iso-itu-t(2) country(16) us(840) organization(1)
+    #:       gov(101) csor(3) nistalgorithm(4) hashalgs(2) 1
+    #:  }
+    #:
+    #: This value uniquely identifies the SHA-256 algorithm.
+    oid = b('\x06\x09\x60\x86\x48\x01\x65\x03\x04\x02\x01')
+
+    digest_size = 32
+    block_size = 64
+
+    def __init__(self, data=None):
+        HashAlgo.__init__(self, hashFactory, data)
+
+    def new(self, data=None):
+        return SHA256Hash(data)
+
+def new(data=None):
+    """Return a fresh instance of the hash object.
+
+    :Parameters:
+       data : byte string
+        The very first chunk of the message to hash.
+        It is equivalent to an early call to `SHA256Hash.update()`.
+        Optional.
+
+    :Return: A `SHA256Hash` object
+    """
+    return SHA256Hash().new(data)
+
+#: The size of the resulting hash in bytes.
+digest_size = SHA256Hash.digest_size
+
+#: The internal block size of the hash algorithm in bytes.
+block_size = SHA256Hash.block_size
+