https://hg.python.org/cpython/rev/70be1f9c9255 changeset: 98890:70be1f9c9255 branch: 3.5 parent: 98887:0e0f3f5195f8 user: Benjamin Peterson <benjamin@python.org> date: Thu Oct 29 20:38:04 2015 -0700 summary: always use os.urandom for the uuid4 algorithm (closes #25515) files: Lib/uuid.py | 26 ++++++-------------------- Misc/NEWS | 2 ++ 2 files changed, 8 insertions(+), 20 deletions(-) diff --git a/Lib/uuid.py b/Lib/uuid.py --- a/Lib/uuid.py +++ b/Lib/uuid.py @@ -44,6 +44,8 @@ UUID('00010203-0405-0607-0809-0a0b0c0d0e0f') """ +import os + __author__ = 'Ka-Ping Yee <ping@zesty.ca>' RESERVED_NCS, RFC_4122, RESERVED_MICROSOFT, RESERVED_FUTURE = [ @@ -456,7 +458,7 @@ # If ctypes is available, use it to find system routines for UUID generation. # XXX This makes the module non-thread-safe! -_uuid_generate_random = _uuid_generate_time = _UuidCreate = None +_uuid_generate_time = _UuidCreate = None try: import ctypes, ctypes.util import sys @@ -471,12 +473,9 @@ lib = ctypes.CDLL(ctypes.util.find_library(libname)) except Exception: continue - if hasattr(lib, 'uuid_generate_random'): - _uuid_generate_random = lib.uuid_generate_random if hasattr(lib, 'uuid_generate_time'): _uuid_generate_time = lib.uuid_generate_time - if _uuid_generate_random is not None: - break # found everything we were looking for + break del _libnames # The uuid_generate_* functions are broken on MacOS X 10.5, as noted @@ -489,7 +488,7 @@ if sys.platform == 'darwin': import os if int(os.uname().release.split('.')[0]) >= 9: - _uuid_generate_random = _uuid_generate_time = None + _uuid_generate_time = None # On Windows prior to 2000, UuidCreate gives a UUID containing the # hardware address. On Windows 2000 and later, UuidCreate makes a @@ -600,20 +599,7 @@ def uuid4(): """Generate a random UUID.""" - - # When the system provides a version-4 UUID generator, use it. - if _uuid_generate_random: - _buffer = ctypes.create_string_buffer(16) - _uuid_generate_random(_buffer) - return UUID(bytes=bytes_(_buffer.raw)) - - # Otherwise, get randomness from urandom or the 'random' module. - try: - import os - return UUID(bytes=os.urandom(16), version=4) - except Exception: - import random - return UUID(int=random.getrandbits(128), version=4) + return UUID(bytes=os.urandom(16), version=4) def uuid5(namespace, name): """Generate a UUID from the SHA-1 hash of a namespace UUID and a name.""" diff --git a/Misc/NEWS b/Misc/NEWS --- a/Misc/NEWS +++ b/Misc/NEWS @@ -48,6 +48,8 @@ - Issue #25503: Fixed inspect.getdoc() for inherited docstrings of properties. Original patch by John Mark Vandenberg. +- Issue #25515: Always use os.urandom as a source of randomness in uuid.uuid4. + - Issue #21827: Fixed textwrap.dedent() for the case when largest common whitespace is a substring of smallest leading whitespace. Based on patch by Robert Li. -- Repository URL: https://hg.python.org/cpython