bpo-32433: Optimized HMAC digest #5023
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Doc/library/hmac.rst
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| Return digest of *msg* for given secret *key* and *digestmod*. The | ||
| function is equivalent to ``HMAC(key, msg, digestmod).digest()``, but | ||
| uses an optimized C or inline implementation, which is faster for messages | ||
| that fit into memory. The parameters *key*, *msg*, and *digestmod* have |
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I realize digestmod matches the parameter name in hmac.new, but it is an antiquated name from the days when the only two hash functions were top level modules. how about just calling it digest on the new API?
Are there any hash function modules with a new method left anywhere that anyone actually uses? Why continue to support that old idiom in new APIs?
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I though about it but then decided to keep the new function compatible to the old PEP.
Since you also dislike the old name, let's use digest in the new function.
Lib/test/test_hmac.py
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| hmac.digest(key, data, digestmod='md5'), | ||
| binascii.unhexlify(digest) | ||
| ) | ||
| orig = hmac._openssl_md_meths |
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from unittest import mock
...
with mock.patch('hmac._openssl_md_meths', {}):
...
tiran
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@gpshead Are you ok with the new code? I'd like to get the feature into 3.7. |
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| def digest(key, msg, digest): | ||
| """Fast inline implementation of HMAC |
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describe the parameters so that interactive users doing help(hmac.digest) see something useful.
| @@ -0,0 +1,2 @@ | |||
| The hmac module now has hmac.digest(), which provides an optimized HMAC | |||
| digest for short messages. | |||
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Is the "for short messages" part true? does anything care how long the message is? I'd just trim those words from the sentence. :)
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"short" for some arbitrary measurement. After all the message has to fit into memory. Anything up to 64kB should be fine. :p
The hmac module now has hmac.digest(), which provides an optimized HMAC digest for short messages. hmac.digest() is up to three times faster than hmac.HMAC().digest(). Signed-off-by: Christian Heimes <christian@python.org>
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@tiran: Please replace |
The hmac module now has hmac.digest(), which provides an optimized HMAC
digest for short messages. hmac.digest() is up to three times faster
than hmac.HMAC().digest().
Signed-off-by: Christian Heimes christian@python.org
https://bugs.python.org/issue32433