File 2293.patch of Package python-cryptography.3244
From 9578e4cadb09f4bca86d66c8f5d7a9370f5bf41e Mon Sep 17 00:00:00 2001
From: Paul Kehrer <paul.l.kehrer@gmail.com>
Date: Mon, 24 Aug 2015 08:00:10 -0500
Subject: [PATCH 1/2] make engine addition idempotent
Weird threading issues keep cropping up. ENGINE_add already
acquires a lock at the C layer via CRYPTO_w_lock (provided you
have registered the locking callbacks) so let's just use that
---
src/cryptography/hazmat/bindings/openssl/binding.py | 19 ++++++++++++++-----
tests/hazmat/bindings/test_openssl.py | 4 ++--
2 files changed, 16 insertions(+), 7 deletions(-)
Index: cryptography-1.0/src/cryptography/hazmat/bindings/openssl/binding.py
===================================================================
--- cryptography-1.0.orig/src/cryptography/hazmat/bindings/openssl/binding.py
+++ cryptography-1.0/src/cryptography/hazmat/bindings/openssl/binding.py
@@ -65,10 +65,6 @@ class Binding(object):
@classmethod
def _register_osrandom_engine(cls):
assert cls.lib.ERR_peek_error() == 0
- looked_up_engine = cls.lib.ENGINE_by_id(cls._osrandom_engine_id)
- if looked_up_engine != ffi.NULL:
- raise RuntimeError("osrandom engine already registered")
-
cls.lib.ERR_clear_error()
engine = cls.lib.ENGINE_new()
@@ -81,7 +77,20 @@ class Binding(object):
result = cls.lib.ENGINE_set_RAND(engine, cls._osrandom_method)
assert result == 1
result = cls.lib.ENGINE_add(engine)
- assert result == 1
+ if result != 1:
+ # Engine already added. Clear the error stack.
+ errors = []
+ while True:
+ code = cls.lib.ERR_get_error()
+ if code == 0:
+ break
+
+ errors.append(code)
+
+ # the following error code corresponds to "conflicting engine
+ # id" in ENGINE_LIST_ADD
+ assert 638025831 in errors
+
finally:
result = cls.lib.ENGINE_free(engine)
assert result == 1
@@ -133,3 +142,6 @@ class Binding(object):
mode, n, file, line
)
)
+
+# init the static locks so we have a locking callback in C for engine init
+Binding.init_static_locks()
Index: cryptography-1.0/tests/hazmat/bindings/test_openssl.py
===================================================================
--- cryptography-1.0.orig/tests/hazmat/bindings/test_openssl.py
+++ cryptography-1.0/tests/hazmat/bindings/test_openssl.py
@@ -89,8 +89,8 @@ class TestOpenSSL(object):
def test_add_engine_more_than_once(self):
b = Binding()
- with pytest.raises(RuntimeError):
- b._register_osrandom_engine()
+ b._register_osrandom_engine()
+ assert b.lib.ERR_get_error() == 0
def test_ssl_ctx_options(self):
# Test that we're properly handling 32-bit unsigned on all platforms.
