Added handling for OpenSSL "xts duplicated keys" error. (#6085)

* Added handling for OpenSSL "xts duplicated keys" error.

Closes #5998

This error value was added pre-OpenSSL 1.1.1d here:
https://github.com/openssl/openssl/commit/2a5f63c9a61be7582620c4b5da202bb3fd7e4138

and refined to only cover encryption shortly after:
https://github.com/openssl/openssl/commit/58ae5a47da1e4843b0cd1846eb297b341d0e7201

* test_aes: Remove unnecessary assignment

* xts: Update duplicated keys check for OpenSSL 3 providers

Also, change the exception message slightly:

- Now matches the tense used by openssl
- Turns out decryption *is* checked for duplicate keys by
  OpenSSL 3 when in FIPS mode

4 files changed, 32 insertions, 1 deletions

diff --git a/src/_cffi_src/openssl/cryptography.py b/src/_cffi_src/openssl/cryptography.py
index e9a9a522e..802a72acb 100644
--- a/src/_cffi_src/openssl/cryptography.py
+++ b/src/_cffi_src/openssl/cryptography.py
@@ -41,6 +41,8 @@ INCLUDES = """
 
 #define CRYPTOGRAPHY_OPENSSL_110F_OR_GREATER \
     (OPENSSL_VERSION_NUMBER >= 0x1010006f && !CRYPTOGRAPHY_IS_LIBRESSL)
+#define CRYPTOGRAPHY_OPENSSL_111D_OR_GREATER \
+    (OPENSSL_VERSION_NUMBER >= 0x10101040 && !CRYPTOGRAPHY_IS_LIBRESSL)
 #define CRYPTOGRAPHY_OPENSSL_300_OR_GREATER \
     (OPENSSL_VERSION_NUMBER >= 0x30000000 && !CRYPTOGRAPHY_IS_LIBRESSL)
 
@@ -62,6 +64,7 @@ INCLUDES = """
 
 TYPES = """
 static const int CRYPTOGRAPHY_OPENSSL_110F_OR_GREATER;
+static const int CRYPTOGRAPHY_OPENSSL_111D_OR_GREATER;
 static const int CRYPTOGRAPHY_OPENSSL_300_OR_GREATER;
 
 static const int CRYPTOGRAPHY_OPENSSL_LESS_THAN_111;
diff --git a/src/_cffi_src/openssl/err.py b/src/_cffi_src/openssl/err.py
index 8cfeaf5ba..54dd1e44c 100644
--- a/src/_cffi_src/openssl/err.py
+++ b/src/_cffi_src/openssl/err.py
@@ -15,6 +15,7 @@ static const int EVP_R_UNSUPPORTED_PRIVATE_KEY_ALGORITHM;
 static const int PKCS12_R_PKCS12_CIPHERFINAL_ERROR;
 static const int PEM_R_UNSUPPORTED_ENCRYPTION;
 static const int EVP_R_UNKNOWN_PBE_ALGORITHM;
+static const int EVP_R_XTS_DUPLICATED_KEYS;
 
 static const int ERR_LIB_EVP;
 static const int ERR_LIB_PEM;
@@ -51,4 +52,8 @@ CUSTOMIZATIONS = """
 #ifndef ERR_LIB_PROV
 #define ERR_LIB_PROV 0
 #endif
+
+#if !CRYPTOGRAPHY_OPENSSL_111D_OR_GREATER
+static const int EVP_R_XTS_DUPLICATED_KEYS = 0;
+#endif
 """
diff --git a/src/_cffi_src/openssl/provider.py b/src/_cffi_src/openssl/provider.py
index d7d659ea5..d741ad7e4 100644
--- a/src/_cffi_src/openssl/provider.py
+++ b/src/_cffi_src/openssl/provider.py
@@ -17,6 +17,7 @@ typedef ... OSSL_PROVIDER;
 typedef ... OSSL_LIB_CTX;
 
 static const long PROV_R_BAD_DECRYPT;
+static const long PROV_R_XTS_DUPLICATED_KEYS;
 static const long PROV_R_WRONG_FINAL_BLOCK_LENGTH;
 """
 
@@ -33,6 +34,7 @@ static const long Cryptography_HAS_PROVIDERS = 0;
 typedef void OSSL_PROVIDER;
 typedef void OSSL_LIB_CTX;
 static const long PROV_R_BAD_DECRYPT = 0;
+static const long PROV_R_XTS_DUPLICATED_KEYS = 0;
 static const long PROV_R_WRONG_FINAL_BLOCK_LENGTH = 0;
 OSSL_PROVIDER *(*OSSL_PROVIDER_load)(OSSL_LIB_CTX *, const char *) = NULL;
 int (*OSSL_PROVIDER_unload)(OSSL_PROVIDER *) = NULL;
diff --git a/src/cryptography/hazmat/backends/openssl/ciphers.py b/src/cryptography/hazmat/backends/openssl/ciphers.py
index eb302e44f..ec272e04d 100644
--- a/src/cryptography/hazmat/backends/openssl/ciphers.py
+++ b/src/cryptography/hazmat/backends/openssl/ciphers.py
@@ -112,7 +112,28 @@ class _CipherContext(object):
             iv_nonce,
             operation,
         )
-        self._backend.openssl_assert(res != 0)
+
+        # Check for XTS mode duplicate keys error
+        errors = self._backend._consume_errors()
+        lib = self._backend._lib
+        if res == 0 and (
+            (
+                lib.CRYPTOGRAPHY_OPENSSL_111D_OR_GREATER
+                and errors[0]._lib_reason_match(
+                    lib.ERR_LIB_EVP, lib.EVP_R_XTS_DUPLICATED_KEYS
+                )
+            )
+            or (
+                lib.Cryptography_HAS_PROVIDERS
+                and errors[0]._lib_reason_match(
+                    lib.ERR_LIB_PROV, lib.PROV_R_XTS_DUPLICATED_KEYS
+                )
+            )
+        ):
+            raise ValueError("In XTS mode duplicated keys are not allowed")
+
+        self._backend.openssl_assert(res != 0, errors=errors)
+
         # We purposely disable padding here as it's handled higher up in the
         # API.
         self._backend._lib.EVP_CIPHER_CTX_set_padding(ctx, 0)