| 1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586878889909192 |
- from __future__ import absolute_import
- import hashlib
- from pip.exceptions import HashMismatch, HashMissing, InstallationError
- from pip.utils import read_chunks
- from pip._vendor.six import iteritems, iterkeys, itervalues
- # The recommended hash algo of the moment. Change this whenever the state of
- # the art changes; it won't hurt backward compatibility.
- FAVORITE_HASH = 'sha256'
- # Names of hashlib algorithms allowed by the --hash option and ``pip hash``
- # Currently, those are the ones at least as collision-resistant as sha256.
- STRONG_HASHES = ['sha256', 'sha384', 'sha512']
- class Hashes(object):
- """A wrapper that builds multiple hashes at once and checks them against
- known-good values
- """
- def __init__(self, hashes=None):
- """
- :param hashes: A dict of algorithm names pointing to lists of allowed
- hex digests
- """
- self._allowed = {} if hashes is None else hashes
- def check_against_chunks(self, chunks):
- """Check good hashes against ones built from iterable of chunks of
- data.
- Raise HashMismatch if none match.
- """
- gots = {}
- for hash_name in iterkeys(self._allowed):
- try:
- gots[hash_name] = hashlib.new(hash_name)
- except (ValueError, TypeError):
- raise InstallationError('Unknown hash name: %s' % hash_name)
- for chunk in chunks:
- for hash in itervalues(gots):
- hash.update(chunk)
- for hash_name, got in iteritems(gots):
- if got.hexdigest() in self._allowed[hash_name]:
- return
- self._raise(gots)
- def _raise(self, gots):
- raise HashMismatch(self._allowed, gots)
- def check_against_file(self, file):
- """Check good hashes against a file-like object
- Raise HashMismatch if none match.
- """
- return self.check_against_chunks(read_chunks(file))
- def check_against_path(self, path):
- with open(path, 'rb') as file:
- return self.check_against_file(file)
- def __nonzero__(self):
- """Return whether I know any known-good hashes."""
- return bool(self._allowed)
- def __bool__(self):
- return self.__nonzero__()
- class MissingHashes(Hashes):
- """A workalike for Hashes used when we're missing a hash for a requirement
- It computes the actual hash of the requirement and raises a HashMissing
- exception showing it to the user.
- """
- def __init__(self):
- """Don't offer the ``hashes`` kwarg."""
- # Pass our favorite hash in to generate a "gotten hash". With the
- # empty list, it will never match, so an error will always raise.
- super(MissingHashes, self).__init__(hashes={FAVORITE_HASH: []})
- def _raise(self, gots):
- raise HashMissing(gots[FAVORITE_HASH].hexdigest())
|
