From 0ae1a0aa54b009ff52e20fb0a43ea9104de799ce Mon Sep 17 00:00:00 2001 From: "Nathaniel J. Smith" Date: Fri, 21 Sep 2018 21:44:12 -0700 Subject: [PATCH] bpo-34759: Fix error handling in ssl 'unwrap()' (GH-9468) OpenSSL follows the convention that whenever you call a function, it returns an error indicator value; and if this value is negative, then you need to go look at the actual error code to see what happened. Commit c6fd1c1c3a introduced a small mistake in _ssl__SSLSocket_shutdown_impl: instead of checking whether the error indicator was negative, it started checking whether the actual error code was negative, and it turns out that the error codes are never negative. So the effect was that 'unwrap()' lost the ability to raise SSL errors. https://bugs.python.org/issue34759 (cherry picked from commit c0da582b227f311126e278b5553a7fa89c79b054) Co-authored-by: Nathaniel J. Smith --- Lib/test/test_ssl.py | 41 +++++++++++++++++++++++++++++++++++++++++ Modules/_ssl.c | 4 ++-- 2 files changed, 43 insertions(+), 2 deletions(-) diff --git a/Lib/test/test_ssl.py b/Lib/test/test_ssl.py index 49a4d7295422950..4d5925a9355ec0f 100644 --- a/Lib/test/test_ssl.py +++ b/Lib/test/test_ssl.py @@ -1735,6 +1735,47 @@ def test_private_init(self): with self.assertRaisesRegex(TypeError, "public constructor"): ssl.SSLObject(bio, bio) + def test_unwrap(self): + client_ctx, server_ctx, hostname = testing_context() + c_in = ssl.MemoryBIO() + c_out = ssl.MemoryBIO() + s_in = ssl.MemoryBIO() + s_out = ssl.MemoryBIO() + client = client_ctx.wrap_bio(c_in, c_out, server_hostname=hostname) + server = server_ctx.wrap_bio(s_in, s_out, server_side=True) + + # Loop on the handshake for a bit to get it settled + for _ in range(5): + try: + client.do_handshake() + except ssl.SSLWantReadError: + pass + if c_out.pending: + s_in.write(c_out.read()) + try: + server.do_handshake() + except ssl.SSLWantReadError: + pass + if s_out.pending: + c_in.write(s_out.read()) + # Now the handshakes should be complete (don't raise WantReadError) + client.do_handshake() + server.do_handshake() + + # Now if we unwrap one side unilaterally, it should send close-notify + # and raise WantReadError: + with self.assertRaises(ssl.SSLWantReadError): + client.unwrap() + + # But server.unwrap() does not raise, because it reads the client's + # close-notify: + s_in.write(c_out.read()) + server.unwrap() + + # And now that the client gets the server's close-notify, it doesn't + # raise either. + c_in.write(s_out.read()) + client.unwrap() class SimpleBackgroundTests(unittest.TestCase): """Tests that connect to a simple server running in the background""" diff --git a/Modules/_ssl.c b/Modules/_ssl.c index 7ff616eacdce66a..faca3a27c562d83 100644 --- a/Modules/_ssl.c +++ b/Modules/_ssl.c @@ -2584,9 +2584,9 @@ _ssl__SSLSocket_shutdown_impl(PySSLSocket *self) break; } - if (err.ssl < 0) { + if (ret < 0) { Py_XDECREF(sock); - return PySSL_SetError(self, err.ssl, __FILE__, __LINE__); + return PySSL_SetError(self, ret, __FILE__, __LINE__); } if (sock) /* It's already INCREF'ed */