Issue 12059: hashlib does not handle missing hash functions correctly (original) (raw)

If one of the hash functions isn't defined in _hashlib, the code suggests it should just be skipped

=== # this one has no builtin implementation, don't define it pass

This doesn't happen however; due to ImportError not being caught the module decides the whole _hashlib module isn't available and tries to fall back to the older individual libraries. You then get thrown an unrelated error about _md5 being unavailable

You can easily replicate this

$ python Python 2.6.6 (r266:84292, Dec 26 2010, 22:31:48) [GCC 4.4.5] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> def foo(): ... raise ValueError ... >>> import _hashlib >>> _hashlib.openssl_sha224 = foo >>> import hashlib Traceback (most recent call last): File "", line 1, in File "/usr/lib/python2.6/hashlib.py", line 136, in md5 = __get_builtin_constructor('md5') File "/usr/lib/python2.6/hashlib.py", line 63, in __get_builtin_constructor import _md5 ImportError: No module named _md5 >>>

I think the solution is to catch the ImportError in __get_builtin_constructor and, if caught, consider the hash function unsupported