Issue #21207: Detect when the os.urandom cached fd has been closed or replaced, and open it anew.

This commit is contained in:
Antoine Pitrou 2014-04-26 14:33:03 +02:00
parent 86fe53e976
commit e472aeafc3
3 changed files with 85 additions and 10 deletions

View file

@ -1070,6 +1070,49 @@ class URandomTests(unittest.TestCase):
"""
assert_python_ok('-c', code)
def test_urandom_fd_closed(self):
# Issue #21207: urandom() should reopen its fd to /dev/urandom if
# closed.
code = """if 1:
import os
import sys
os.urandom(4)
os.closerange(3, 256)
sys.stdout.buffer.write(os.urandom(4))
"""
rc, out, err = assert_python_ok('-Sc', code)
def test_urandom_fd_reopened(self):
# Issue #21207: urandom() should detect its fd to /dev/urandom
# changed to something else, and reopen it.
with open(support.TESTFN, 'wb') as f:
f.write(b"x" * 256)
self.addCleanup(os.unlink, support.TESTFN)
code = """if 1:
import os
import sys
os.urandom(4)
for fd in range(3, 256):
try:
os.close(fd)
except OSError:
pass
else:
# Found the urandom fd (XXX hopefully)
break
os.closerange(3, 256)
with open({TESTFN!r}, 'rb') as f:
os.dup2(f.fileno(), fd)
sys.stdout.buffer.write(os.urandom(4))
sys.stdout.buffer.write(os.urandom(4))
""".format(TESTFN=support.TESTFN)
rc, out, err = assert_python_ok('-Sc', code)
self.assertEqual(len(out), 8)
self.assertNotEqual(out[0:4], out[4:8])
rc, out2, err2 = assert_python_ok('-Sc', code)
self.assertEqual(len(out2), 8)
self.assertNotEqual(out2, out)
@contextlib.contextmanager
def _execvpe_mockup(defpath=None):