ref: e64efe273fcb921a61bf27d33b230c4e64fcd425
dir: /sys/lib/python/hashlib.py/
# $Id: hashlib.py 52533 2006-10-29 18:01:12Z georg.brandl $ # # Copyright (C) 2005 Gregory P. Smith (greg@electricrain.com) # Licensed to PSF under a Contributor Agreement. # __doc__ = """hashlib module - A common interface to many hash functions. new(name, string='') - returns a new hash object implementing the given hash function; initializing the hash using the given string data. Named constructor functions are also available, these are much faster than using new(): md5(), sha1(), sha224(), sha256(), sha384(), and sha512() More algorithms may be available on your platform but the above are guaranteed to exist. Choose your hash function wisely. Some have known collision weaknesses. sha384 and sha512 will be slow on 32 bit platforms. Hash objects have these methods: - update(arg): Update the hash object with the string arg. Repeated calls are equivalent to a single call with the concatenation of all the arguments. - digest(): Return the digest of the strings passed to the update() method so far. This may contain non-ASCII characters, including NUL bytes. - hexdigest(): Like digest() except the digest is returned as a string of double length, containing only hexadecimal digits. - copy(): Return a copy (clone) of the hash object. This can be used to efficiently compute the digests of strings that share a common initial substring. For example, to obtain the digest of the string 'Nobody inspects the spammish repetition': >>> import hashlib >>> m = hashlib.md5() >>> m.update("Nobody inspects") >>> m.update(" the spammish repetition") >>> m.digest() '\xbbd\x9c\x83\xdd\x1e\xa5\xc9\xd9\xde\xc9\xa1\x8d\xf0\xff\xe9' More condensed: >>> hashlib.sha224("Nobody inspects the spammish repetition").hexdigest() 'a4337bc45a8fc544c03f52dc550cd6e1e87021bc896588bd79e901e2' """ try: import _sechash md5 = _sechash.md5 sha1 = _sechash.sha1 sha224 = _sechash.sha224 sha256 = _sechash.sha256 sha384 = _sechash.sha384 sha512 = _sechash.sha512 except ImportError: import _hashlib md5 = _hashlib.openssl_md5 sha1 = _hashlib.openssl_sha1 sha224 = _hashlib.openssl_sha224 sha256 = _hashlib.openssl_sha256 sha384 = _hashlib.openssl_sha384 sha512 = _hashlib.openssl_sha512 algs = dict() for a in [md5, sha1, sha224, sha256, sha384, sha512]: algs[a().name.lower()] = a def new(name, string=''): """new(name, string='') - Return a new hashing object using the named algorithm; optionally initialized with a string. """ a = algs[name.lower()] if a != None: return a(string) raise ValueError, "unsupported hash type"