From ca92d13436944090faa79ffc25378c45ec564a4d Mon Sep 17 00:00:00 2001
From: Alex Gaynor <alex.gaynor@gmail.com>
Date: Wed, 14 Dec 2022 01:50:06 -0500
Subject: [PATCH] Adapt for OpenSSL RSA bleichenbacher mitigation (#7895)

Attempt to work-around wycheproof tests
---
 src/_cffi_src/openssl/rsa.py        |  8 ++++++++
 tests/hazmat/primitives/test_rsa.py |  5 +++--
 tests/wycheproof/test_rsa.py        | 20 +++++++++++++++-----
 3 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/src/_cffi_src/openssl/rsa.py b/src/_cffi_src/openssl/rsa.py
index 5d1e163b1..2682ea1e4 100644
--- a/src/_cffi_src/openssl/rsa.py
+++ b/src/_cffi_src/openssl/rsa.py
@@ -18,6 +18,8 @@ static const int RSA_F4;
 
 static const int Cryptography_HAS_RSA_OAEP_MD;
 static const int Cryptography_HAS_RSA_OAEP_LABEL;
+
+static const int Cryptography_HAS_IMPLICIT_RSA_REJECTION;
 """
 
 FUNCTIONS = """
@@ -57,4 +59,10 @@ int (*EVP_PKEY_CTX_set_rsa_oaep_md)(EVP_PKEY_CTX *, EVP_MD *) = NULL;
 int (*EVP_PKEY_CTX_set0_rsa_oaep_label)(EVP_PKEY_CTX *, unsigned char *,
                                         int) = NULL;
 #endif
+
+#if defined(EVP_PKEY_CTRL_RSA_IMPLICIT_REJECTION)
+static const int Cryptography_HAS_IMPLICIT_RSA_REJECTION = 1;
+#else
+static const int Cryptography_HAS_IMPLICIT_RSA_REJECTION = 0;
+#endif
 """
diff --git a/tests/hazmat/primitives/test_rsa.py b/tests/hazmat/primitives/test_rsa.py
index 4fb205db4..0315489dc 100644
--- a/tests/hazmat/primitives/test_rsa.py
+++ b/tests/hazmat/primitives/test_rsa.py
@@ -1551,8 +1551,9 @@ class TestRSADecryption(object):
             private_key.decrypt(b"0" * 256, DummyAsymmetricPadding())
 
     @pytest.mark.supported(
-        only_if=lambda backend: backend.rsa_padding_supported(
-            padding.PKCS1v15()
+        only_if=lambda backend: (
+            backend.rsa_padding_supported(padding.PKCS1v15())
+            and not backend._lib.Cryptography_HAS_IMPLICIT_RSA_REJECTION
         ),
         skip_message="Does not support PKCS1v1.5.",
     )
diff --git a/tests/wycheproof/test_rsa.py b/tests/wycheproof/test_rsa.py
index 79fd682b7..e6bd8af8a 100644
--- a/tests/wycheproof/test_rsa.py
+++ b/tests/wycheproof/test_rsa.py
@@ -245,8 +245,18 @@ def test_rsa_pkcs1_encryption(backend, wycheproof):
         )
         assert pt == binascii.unhexlify(wycheproof.testcase["msg"])
     else:
-        with pytest.raises(ValueError):
-            key.decrypt(
-                binascii.unhexlify(wycheproof.testcase["ct"]),
-                padding.PKCS1v15(),
-            )
+        if backend._lib.Cryptography_HAS_IMPLICIT_RSA_REJECTION:
+            try:
+                assert key.decrypt(
+                    binascii.unhexlify(wycheproof.testcase["ct"]),
+                    padding.PKCS1v15(),
+                ) != binascii.unhexlify(wycheproof.testcase["ct"])
+            except ValueError:
+                # Some raise ValueError due to length mismatch.
+                pass
+        else:
+            with pytest.raises(ValueError):
+                key.decrypt(
+                    binascii.unhexlify(wycheproof.testcase["ct"]),
+                    padding.PKCS1v15(),
+                )
-- 
2.40.1