/// <summary> /// Decrypts the symmetric key and saves it in metadata. /// </summary> internal static void DecryptSymmetricKey(SqlTceCipherInfoEntry sqlTceCipherInfoEntry, out SqlClientSymmetricKey sqlClientSymmetricKey, out SqlEncryptionKeyInfo encryptionkeyInfoChosen, SqlConnection connection, SqlCommand command) { Debug.Assert(sqlTceCipherInfoEntry is not null, "sqlTceCipherInfoEntry should not be null in DecryptSymmetricKey."); Debug.Assert(sqlTceCipherInfoEntry.ColumnEncryptionKeyValues is not null, "sqlTceCipherInfoEntry.ColumnEncryptionKeyValues should not be null in DecryptSymmetricKey."); sqlClientSymmetricKey = null; encryptionkeyInfoChosen = null; Exception lastException = null; SqlSymmetricKeyCache globalCekCache = SqlSymmetricKeyCache.GetInstance(); foreach (SqlEncryptionKeyInfo keyInfo in sqlTceCipherInfoEntry.ColumnEncryptionKeyValues) { try { sqlClientSymmetricKey = ShouldUseInstanceLevelProviderFlow(keyInfo.keyStoreName, connection, command) ? GetKeyFromLocalProviders(keyInfo, connection, command) : globalCekCache.GetKey(keyInfo, connection, command); encryptionkeyInfoChosen = keyInfo; break; } catch (Exception e) { lastException = e; } } if (sqlClientSymmetricKey is null) { Debug.Assert(lastException is not null, "CEK decryption failed without raising exceptions"); throw lastException; } Debug.Assert(encryptionkeyInfoChosen is not null, "encryptionkeyInfoChosen must have a value."); }
/// <summary> /// <para> Decrypts the symmetric key and saves it in metadata. /// </summary> internal static void DecryptSymmetricKey(SqlTceCipherInfoEntry?sqlTceCipherInfoEntry, string serverName, out SqlClientSymmetricKey sqlClientSymmetricKey, out SqlEncryptionKeyInfo?encryptionkeyInfoChosen) { Debug.Assert(serverName != null, @"serverName should not be null in DecryptSymmetricKey."); Debug.Assert(sqlTceCipherInfoEntry.HasValue, "sqlTceCipherInfoEntry should not be null in DecryptSymmetricKey."); Debug.Assert(sqlTceCipherInfoEntry.Value.ColumnEncryptionKeyValues != null, "sqlTceCipherInfoEntry.ColumnEncryptionKeyValues should not be null in DecryptSymmetricKey."); sqlClientSymmetricKey = null; encryptionkeyInfoChosen = null; Exception lastException = null; SqlSymmetricKeyCache cache = SqlSymmetricKeyCache.GetInstance(); foreach (SqlEncryptionKeyInfo keyInfo in sqlTceCipherInfoEntry.Value.ColumnEncryptionKeyValues) { try { if (cache.GetKey(keyInfo, serverName, out sqlClientSymmetricKey)) { encryptionkeyInfoChosen = keyInfo; break; } } catch (Exception e) { lastException = e; } } if (null == sqlClientSymmetricKey) { Debug.Assert(null != lastException, "CEK decryption failed without raising exceptions"); throw lastException; } Debug.Assert(encryptionkeyInfoChosen.HasValue, "encryptionkeyInfoChosen must have a value."); }