diff options
Diffstat (limited to 'Lib/hmac.py')
| -rw-r--r-- | Lib/hmac.py | 53 |
1 files changed, 29 insertions, 24 deletions
diff --git a/Lib/hmac.py b/Lib/hmac.py index 890eaba08e..b769876e6f 100644 --- a/Lib/hmac.py +++ b/Lib/hmac.py @@ -1,4 +1,4 @@ -"""HMAC (Keyed-Hashing for Message Authentication) Python module. +"""HMAC (Keyed-Hashing for Message Authentication) module. Implements the HMAC algorithm as described by RFC 2104. """ @@ -30,23 +30,25 @@ class HMAC: """ blocksize = 64 # 512-bit HMAC; can be changed in subclasses. - def __init__(self, key, msg = None, digestmod = None): + def __init__(self, key, msg=None, digestmod=''): """Create a new HMAC object. - key: key for the keyed hash object. - msg: Initial input for the hash, if provided. - digestmod: Required. A module supporting PEP 247. *OR* - A hashlib constructor returning a new hash object. *OR* - A hash name suitable for hashlib.new(). + key: bytes or buffer, key for the keyed hash object. + msg: bytes or buffer, Initial input for the hash or None. + digestmod: A hash name suitable for hashlib.new(). *OR* + A hashlib constructor returning a new hash object. *OR* + A module supporting PEP 247. - Note: key and msg must be a bytes or bytearray objects. + Required as of 3.8, despite its position after the optional + msg argument. Passing it as a keyword argument is + recommended, though not required for legacy API reasons. """ if not isinstance(key, (bytes, bytearray)): raise TypeError("key: expected bytes or bytearray, but got %r" % type(key).__name__) - if digestmod is None: - raise ValueError('`digestmod` is required.') + if not digestmod: + raise TypeError("Missing required parameter 'digestmod'.") if callable(digestmod): self.digest_cons = digestmod @@ -90,8 +92,7 @@ class HMAC: return "hmac-" + self.inner.name def update(self, msg): - """Update this hashing object with the string msg. - """ + """Feed data from msg into this hashing object.""" self.inner.update(msg) def copy(self): @@ -119,7 +120,7 @@ class HMAC: def digest(self): """Return the hash value of this hashing object. - This returns a string containing 8-bit data. The object is + This returns the hmac value as bytes. The object is not altered in any way by this function; you can continue updating the object after calling this function. """ @@ -132,30 +133,34 @@ class HMAC: h = self._current() return h.hexdigest() -def new(key, msg = None, digestmod = None): +def new(key, msg=None, digestmod=''): """Create a new hashing object and return it. - key: The starting key for the hash. - msg: if available, will immediately be hashed into the object's starting - state. + key: bytes or buffer, The starting key for the hash. + msg: bytes or buffer, Initial input for the hash, or None. + digestmod: A hash name suitable for hashlib.new(). *OR* + A hashlib constructor returning a new hash object. *OR* + A module supporting PEP 247. + + Required as of 3.8, despite its position after the optional + msg argument. Passing it as a keyword argument is + recommended, though not required for legacy API reasons. - You can now feed arbitrary strings into the object using its update() + You can now feed arbitrary bytes into the object using its update() method, and can ask for the hash value at any time by calling its digest() - method. + or hexdigest() methods. """ return HMAC(key, msg, digestmod) def digest(key, msg, digest): - """Fast inline implementation of HMAC + """Fast inline implementation of HMAC. - key: key for the keyed hash object. - msg: input message + key: bytes or buffer, The key for the keyed hash object. + msg: bytes or buffer, Input message. digest: A hash name suitable for hashlib.new() for best performance. *OR* A hashlib constructor returning a new hash object. *OR* A module supporting PEP 247. - - Note: key and msg must be a bytes or bytearray objects. """ if (_hashopenssl is not None and isinstance(digest, str) and digest in _openssl_md_meths): |