Exemple illustrant l’utilisation du fournisseur Azure Key Vault avec Always Encrypted activé avec des enclaves sécurisées

S’applique à : SQL Server 2019 (15.x) et versions ultérieures - Windows uniquement Azure SQL Database

S'applique à : .NET Framework .NET .NET Standard

Cet exemple vous montre comment utiliser le fournisseur Azure Key Vault avec Always Encrypted avec enclaves sécurisées. Le script crée une clé principale de colonne dans la base de données en fonction de l’URL d’Azure Key Vault. Ensuite, une clé de chiffrement de colonne est créée. Une fois les clés créées, une table avec des colonnes chiffrées est créée, quelques enregistrements sont insérés et lus à nouveau à partir de la table.

AzureKeyVaultProvider version 2.0 ou ultérieure

using System.Collections.Generic;
using System.Security.Cryptography;
using System.Threading.Tasks;
using Azure.Identity;
using Microsoft.Data.SqlClient;
using Microsoft.Data.SqlClient.AlwaysEncrypted.AzureKeyVaultProvider;

namespace AKVEnclaveExample
{
    class Program
    {
        static readonly string s_algorithm = "RSA_OAEP";

        // ********* Provide details here ***********
        static readonly string s_akvUrl = "https://{KeyVaultName}.vault.azure.net/keys/{Key}/{KeyIdentifier}";
        static readonly string s_connectionString = "Server={Server}; Database={database}; Integrated Security=true; Column Encryption Setting=Enabled; Attestation Protocol=HGS; Enclave Attestation Url = {attestation_url_for_HGS};";
        // ******************************************

        static void Main(string[] args)
        {
            // Initialize Token Credential instance using InteractiveBrowserCredential. For other authentication options,
            // see classes derived from TokenCredential: https://docs.microsoft.com/dotnet/api/azure.core.tokencredential
            InteractiveBrowserCredential interactiveBrowserCredential = new InteractiveBrowserCredential();
            
            // Initialize AKV provider
            SqlColumnEncryptionAzureKeyVaultProvider akvProvider = new SqlColumnEncryptionAzureKeyVaultProvider(interactiveBrowserCredential);

            // Register AKV provider
            SqlConnection.RegisterColumnEncryptionKeyStoreProviders(customProviders: new Dictionary<string, SqlColumnEncryptionKeyStoreProvider>(capacity: 1, comparer: StringComparer.OrdinalIgnoreCase)
                {
                    { SqlColumnEncryptionAzureKeyVaultProvider.ProviderName, akvProvider}
                });
            Console.WriteLine("AKV provider Registered");

            // Create connection to database
            using (SqlConnection sqlConnection = new SqlConnection(s_connectionString))
            {
                string cmkName = "CMK_WITH_AKV";
                string cekName = "CEK_WITH_AKV";
                string tblName = "AKV_TEST_TABLE";

                CustomerRecord customer = new CustomerRecord(1, @"Microsoft", @"Corporation");

                try
                {
                    sqlConnection.Open();

                    // Drop Objects if exists
                    dropObjects(sqlConnection, cmkName, cekName, tblName);

                    // Create Column Master Key with AKV Url
                    createCMK(sqlConnection, cmkName, akvProvider);
                    Console.WriteLine("Column Master Key created.");

                    // Create Column Encryption Key
                    createCEK(sqlConnection, cmkName, cekName, akvProvider);
                    Console.WriteLine("Column Encryption Key created.");

                    // Create Table with Encrypted Columns
                    createTbl(sqlConnection, cekName, tblName);
                    Console.WriteLine("Table created with Encrypted columns.");

                    // Insert Customer Record in table
                    insertData(sqlConnection, tblName, customer);
                    Console.WriteLine("Encryted data inserted.");

                    // Read data from table
                    verifyData(sqlConnection, tblName, customer);
                    Console.WriteLine("Data validated successfully.");
                }
                finally
                {
                    // Drop table and keys
                    dropObjects(sqlConnection, cmkName, cekName, tblName);
                    Console.WriteLine("Dropped Table, CEK and CMK");
                }

                Console.WriteLine("Completed AKV provider Sample.");
            }
        }

        private static void createCMK(SqlConnection sqlConnection, string cmkName, SqlColumnEncryptionAzureKeyVaultProvider sqlColumnEncryptionAzureKeyVaultProvider)
        {
            string KeyStoreProviderName = SqlColumnEncryptionAzureKeyVaultProvider.ProviderName;

            byte[] cmkSign = sqlColumnEncryptionAzureKeyVaultProvider.SignColumnMasterKeyMetadata(s_akvUrl, true);
            string cmkSignStr = string.Concat("0x", BitConverter.ToString(cmkSign).Replace("-", string.Empty));

            string sql =
                $@"CREATE COLUMN MASTER KEY [{cmkName}]
                    WITH (
                        KEY_STORE_PROVIDER_NAME = N'{KeyStoreProviderName}',
                        KEY_PATH = N'{s_akvUrl}',
                        ENCLAVE_COMPUTATIONS (SIGNATURE = {cmkSignStr})
                    );";

            using (SqlCommand command = sqlConnection.CreateCommand())
            {
                command.CommandText = sql;
                command.ExecuteNonQuery();
            }
        }

        private static void createCEK(SqlConnection sqlConnection, string cmkName, string cekName, SqlColumnEncryptionAzureKeyVaultProvider sqlColumnEncryptionAzureKeyVaultProvider)
        {
            string sql =
                    $@"CREATE COLUMN ENCRYPTION KEY [{cekName}] 
                        WITH VALUES (
                            COLUMN_MASTER_KEY = [{cmkName}],
                            ALGORITHM = '{s_algorithm}', 
                            ENCRYPTED_VALUE = {GetEncryptedValue(sqlColumnEncryptionAzureKeyVaultProvider)}
                        )";

            using (SqlCommand command = sqlConnection.CreateCommand())
            {
                command.CommandText = sql;
                command.ExecuteNonQuery();
            }
        }

        private static string GetEncryptedValue(SqlColumnEncryptionAzureKeyVaultProvider sqlColumnEncryptionAzureKeyVaultProvider)
        {
            byte[] plainTextColumnEncryptionKey = new byte[32];
            RandomNumberGenerator rng = RandomNumberGenerator.Create();
            rng.GetBytes(plainTextColumnEncryptionKey);

            byte[] encryptedColumnEncryptionKey = sqlColumnEncryptionAzureKeyVaultProvider.EncryptColumnEncryptionKey(s_akvUrl, s_algorithm, plainTextColumnEncryptionKey);
            string EncryptedValue = string.Concat("0x", BitConverter.ToString(encryptedColumnEncryptionKey).Replace("-", string.Empty));
            return EncryptedValue;
        }

        private static void createTbl(SqlConnection sqlConnection, string cekName, string tblName)
        {
            string ColumnEncryptionAlgorithmName = @"AEAD_AES_256_CBC_HMAC_SHA_256";

            string sql =
                    $@"CREATE TABLE [dbo].[{tblName}]
                (
                    [CustomerId] [int] ENCRYPTED WITH (COLUMN_ENCRYPTION_KEY = [{cekName}], ENCRYPTION_TYPE = RANDOMIZED, ALGORITHM = '{ColumnEncryptionAlgorithmName}'),
                    [FirstName] [nvarchar](50) COLLATE Latin1_General_BIN2 ENCRYPTED WITH (COLUMN_ENCRYPTION_KEY = [{cekName}], ENCRYPTION_TYPE = RANDOMIZED, ALGORITHM = '{ColumnEncryptionAlgorithmName}'),
                    [LastName] [nvarchar](50) COLLATE Latin1_General_BIN2 ENCRYPTED WITH (COLUMN_ENCRYPTION_KEY = [{cekName}], ENCRYPTION_TYPE = RANDOMIZED, ALGORITHM = '{ColumnEncryptionAlgorithmName}')
                )";

            using (SqlCommand command = sqlConnection.CreateCommand())
            {
                command.CommandText = sql;
                command.ExecuteNonQuery();
            }
        }

        private static void insertData(SqlConnection sqlConnection, string tblName, CustomerRecord customer)
        {
            string insertSql = $"INSERT INTO [{tblName}] (CustomerId, FirstName, LastName) VALUES (@CustomerId, @FirstName, @LastName);";

            using (SqlTransaction sqlTransaction = sqlConnection.BeginTransaction())
            using (SqlCommand sqlCommand = new SqlCommand(insertSql,
            connection: sqlConnection, transaction: sqlTransaction,
            columnEncryptionSetting: SqlCommandColumnEncryptionSetting.Enabled))
            {
                sqlCommand.Parameters.AddWithValue(@"CustomerId", customer.Id);
                sqlCommand.Parameters.AddWithValue(@"FirstName", customer.FirstName);
                sqlCommand.Parameters.AddWithValue(@"LastName", customer.LastName);

                sqlCommand.ExecuteNonQuery();
                sqlTransaction.Commit();
            }
        }

        private static void verifyData(SqlConnection sqlConnection, string tblName, CustomerRecord customer)
        {
            // Test INPUT parameter on an encrypted parameter
            using (SqlCommand sqlCommand = new SqlCommand($"SELECT CustomerId, FirstName, LastName FROM [{tblName}] WHERE FirstName = @firstName", sqlConnection))
            {
                SqlParameter customerFirstParam = sqlCommand.Parameters.AddWithValue(@"firstName", @"Microsoft");
                customerFirstParam.Direction = System.Data.ParameterDirection.Input;
                customerFirstParam.ForceColumnEncryption = true;

                using (SqlDataReader sqlDataReader = sqlCommand.ExecuteReader())
                {
                    ValidateResultSet(sqlDataReader);
                }
            }
        }

        private static void ValidateResultSet(SqlDataReader sqlDataReader)
        {
            Console.WriteLine(" * Row available: " + sqlDataReader.HasRows);

            while (sqlDataReader.Read())
            {
                if (sqlDataReader.GetInt32(0) == 1)
                {
                    Console.WriteLine(" * Employee Id received as sent: " + sqlDataReader.GetInt32(0));
                }
                else
                {
                    Console.WriteLine("Employee Id didn't match");
                }

                if (sqlDataReader.GetString(1) == @"Microsoft")
                {
                    Console.WriteLine(" * Employee Firstname received as sent: " + sqlDataReader.GetString(1));
                }
                else
                {
                    Console.WriteLine("Employee FirstName didn't match.");
                }

                if (sqlDataReader.GetString(2) == @"Corporation")
                {
                    Console.WriteLine(" * Employee LastName received as sent: " + sqlDataReader.GetString(2));
                }
                else
                {
                    Console.WriteLine("Employee LastName didn't match.");
                }
            }
        }

        private static void dropObjects(SqlConnection sqlConnection, string cmkName, string cekName, string tblName)
        {
            using (SqlCommand cmd = sqlConnection.CreateCommand())
            {
                cmd.CommandText = $@"IF EXISTS (select * from sys.objects where name = '{tblName}') BEGIN DROP TABLE [{tblName}] END";
                cmd.ExecuteNonQuery();
                cmd.CommandText = $@"IF EXISTS (select * from sys.column_encryption_keys where name = '{cekName}') BEGIN DROP COLUMN ENCRYPTION KEY [{cekName}] END";
                cmd.ExecuteNonQuery();
                cmd.CommandText = $@"IF EXISTS (select * from sys.column_master_keys where name = '{cmkName}') BEGIN DROP COLUMN MASTER KEY [{cmkName}] END";
                cmd.ExecuteNonQuery();
            }
        }

        private class CustomerRecord
        {
            internal int Id { get; set; }
            internal string FirstName { get; set; }
            internal string LastName { get; set; }

            public CustomerRecord(int id, string fName, string lName)
            {
                Id = id;
                FirstName = fName;
                LastName = lName;
            }
        }
    }
}

AzureKeyVaultProvider version 1.x

using System.Collections.Generic;
using System.Security.Cryptography;
using System.Threading.Tasks;
using Microsoft.Data.SqlClient;
using Microsoft.Data.SqlClient.AlwaysEncrypted.AzureKeyVaultProvider;
using Microsoft.IdentityModel.Clients.ActiveDirectory;

namespace AKVEnclaveExample
{
    class Program
    {
        static readonly string s_algorithm = "RSA_OAEP";

        // ********* Provide details here ***********
        static readonly string s_akvUrl = "https://{KeyVaultName}.vault.azure.net/keys/{Key}/{KeyIdentifier}";
        static readonly string s_clientId = "{Application_Client_ID}";
        static readonly string s_clientSecret = "{Application_Client_Secret}";
        static readonly string s_connectionString = "Server={Server}; Database={database}; Integrated Security=true; Column Encryption Setting=Enabled; Attestation Protocol=HGS; Enclave Attestation Url = {attestation_url_for_HGS};";
        // ******************************************

        static void Main(string[] args)
        {
            // Initialize AKV provider
            SqlColumnEncryptionAzureKeyVaultProvider sqlColumnEncryptionAzureKeyVaultProvider = new SqlColumnEncryptionAzureKeyVaultProvider(AzureActiveDirectoryAuthenticationCallback);

            // Register AKV provider
            SqlConnection.RegisterColumnEncryptionKeyStoreProviders(customProviders: new Dictionary<string, SqlColumnEncryptionKeyStoreProvider>(capacity: 1, comparer: StringComparer.OrdinalIgnoreCase)
                {
                    { SqlColumnEncryptionAzureKeyVaultProvider.ProviderName, sqlColumnEncryptionAzureKeyVaultProvider}
                });
            Console.WriteLine("AKV provider Registered");

            // Create connection to database
            using (SqlConnection sqlConnection = new SqlConnection(s_connectionString))
            {
                string cmkName = "CMK_WITH_AKV";
                string cekName = "CEK_WITH_AKV";
                string tblName = "AKV_TEST_TABLE";

                CustomerRecord customer = new CustomerRecord(1, @"Microsoft", @"Corporation");

                try
                {
                    sqlConnection.Open();

                    // Drop Objects if exists
                    dropObjects(sqlConnection, cmkName, cekName, tblName);

                    // Create Column Master Key with AKV Url
                    createCMK(sqlConnection, cmkName, sqlColumnEncryptionAzureKeyVaultProvider);
                    Console.WriteLine("Column Master Key created.");

                    // Create Column Encryption Key
                    createCEK(sqlConnection, cmkName, cekName, sqlColumnEncryptionAzureKeyVaultProvider);
                    Console.WriteLine("Column Encryption Key created.");

                    // Create Table with Encrypted Columns
                    createTbl(sqlConnection, cekName, tblName);
                    Console.WriteLine("Table created with Encrypted columns.");

                    // Insert Customer Record in table
                    insertData(sqlConnection, tblName, customer);
                    Console.WriteLine("Encryted data inserted.");

                    // Read data from table
                    verifyData(sqlConnection, tblName, customer);
                    Console.WriteLine("Data validated successfully.");
                }
                finally
                {
                    // Drop table and keys
                    dropObjects(sqlConnection, cmkName, cekName, tblName);
                    Console.WriteLine("Dropped Table, CEK and CMK");
                }

                Console.WriteLine("Completed AKV provider Sample.");

                Console.ReadKey();
            }
        }

        public static async Task<string> AzureActiveDirectoryAuthenticationCallback(string authority, string resource, string scope)
        {
            var authContext = new AuthenticationContext(authority);
            ClientCredential clientCred = new ClientCredential(s_clientId, s_clientSecret);
            AuthenticationResult result = await authContext.AcquireTokenAsync(resource, clientCred);
            if (result == null)
            {
                throw new InvalidOperationException($"Failed to retrieve an access token for {resource}");
            }

            return result.AccessToken;
        }

        private static void createCMK(SqlConnection sqlConnection, string cmkName, SqlColumnEncryptionAzureKeyVaultProvider sqlColumnEncryptionAzureKeyVaultProvider)
        {
            string KeyStoreProviderName = SqlColumnEncryptionAzureKeyVaultProvider.ProviderName;

            byte[] cmkSign = sqlColumnEncryptionAzureKeyVaultProvider.SignColumnMasterKeyMetadata(s_akvUrl, true);
            string cmkSignStr = string.Concat("0x", BitConverter.ToString(cmkSign).Replace("-", string.Empty));

            string sql =
                $@"CREATE COLUMN MASTER KEY [{cmkName}]
                    WITH (
                        KEY_STORE_PROVIDER_NAME = N'{KeyStoreProviderName}',
                        KEY_PATH = N'{s_akvUrl}',
                        ENCLAVE_COMPUTATIONS (SIGNATURE = {cmkSignStr})
                    );";

            using (SqlCommand command = sqlConnection.CreateCommand())
            {
                command.CommandText = sql;
                command.ExecuteNonQuery();
            }
        }

        private static void createCEK(SqlConnection sqlConnection, string cmkName, string cekName, SqlColumnEncryptionAzureKeyVaultProvider sqlColumnEncryptionAzureKeyVaultProvider)
        {
            string sql =
                $@"CREATE COLUMN ENCRYPTION KEY [{cekName}] 
                    WITH VALUES (
                        COLUMN_MASTER_KEY = [{cmkName}],
                        ALGORITHM = '{s_algorithm}', 
                        ENCRYPTED_VALUE = {GetEncryptedValue(sqlColumnEncryptionAzureKeyVaultProvider)}
                    )";

            using (SqlCommand command = sqlConnection.CreateCommand())
            {
                command.CommandText = sql;
                command.ExecuteNonQuery();
            }
        }

        private static string GetEncryptedValue(SqlColumnEncryptionAzureKeyVaultProvider sqlColumnEncryptionAzureKeyVaultProvider)
        {
            byte[] plainTextColumnEncryptionKey = new byte[32];
            RandomNumberGenerator rng = RandomNumberGenerator.Create();
            rng.GetBytes(plainTextColumnEncryptionKey);

            byte[] encryptedColumnEncryptionKey = sqlColumnEncryptionAzureKeyVaultProvider.EncryptColumnEncryptionKey(s_akvUrl, s_algorithm, plainTextColumnEncryptionKey);
            string EncryptedValue = string.Concat("0x", BitConverter.ToString(encryptedColumnEncryptionKey).Replace("-", string.Empty));
            return EncryptedValue;
        }

        private static void createTbl(SqlConnection sqlConnection, string cekName, string tblName)
        {
            string ColumnEncryptionAlgorithmName = @"AEAD_AES_256_CBC_HMAC_SHA_256";

            string sql =
                    $@"CREATE TABLE [dbo].[{tblName}]
                (
                    [CustomerId] [int] ENCRYPTED WITH (COLUMN_ENCRYPTION_KEY = [{cekName}], ENCRYPTION_TYPE = RANDOMIZED, ALGORITHM = '{ColumnEncryptionAlgorithmName}'),
                    [FirstName] [nvarchar](50) COLLATE Latin1_General_BIN2 ENCRYPTED WITH (COLUMN_ENCRYPTION_KEY = [{cekName}], ENCRYPTION_TYPE = RANDOMIZED, ALGORITHM = '{ColumnEncryptionAlgorithmName}'),
                    [LastName] [nvarchar](50) COLLATE Latin1_General_BIN2 ENCRYPTED WITH (COLUMN_ENCRYPTION_KEY = [{cekName}], ENCRYPTION_TYPE = RANDOMIZED, ALGORITHM = '{ColumnEncryptionAlgorithmName}')
                )";

            using (SqlCommand command = sqlConnection.CreateCommand())
            {
                command.CommandText = sql;
                command.ExecuteNonQuery();
            }
        }

        private static void insertData(SqlConnection sqlConnection, string tblName, CustomerRecord customer)
        {
            string insertSql = $"INSERT INTO [{tblName}] (CustomerId, FirstName, LastName) VALUES (@CustomerId, @FirstName, @LastName);";

            using (SqlTransaction sqlTransaction = sqlConnection.BeginTransaction())
            using (SqlCommand sqlCommand = new SqlCommand(insertSql,
            connection: sqlConnection, transaction: sqlTransaction,
            columnEncryptionSetting: SqlCommandColumnEncryptionSetting.Enabled))
            {
                sqlCommand.Parameters.AddWithValue(@"CustomerId", customer.Id);
                sqlCommand.Parameters.AddWithValue(@"FirstName", customer.FirstName);
                sqlCommand.Parameters.AddWithValue(@"LastName", customer.LastName);

                sqlCommand.ExecuteNonQuery();
                sqlTransaction.Commit();
            }
        }

        private static void verifyData(SqlConnection sqlConnection, string tblName, CustomerRecord customer)
        {
            // Test INPUT parameter on an encrypted parameter
            using (SqlCommand sqlCommand = new SqlCommand($"SELECT CustomerId, FirstName, LastName FROM [{tblName}] WHERE FirstName = @firstName",
                                                            sqlConnection))
            {
                SqlParameter customerFirstParam = sqlCommand.Parameters.AddWithValue(@"firstName", @"Microsoft");
                customerFirstParam.Direction = System.Data.ParameterDirection.Input;
                customerFirstParam.ForceColumnEncryption = true;

                using (SqlDataReader sqlDataReader = sqlCommand.ExecuteReader())
                {
                    ValidateResultSet(sqlDataReader);
                }
            }
        }

        private static void ValidateResultSet(SqlDataReader sqlDataReader)
        {
            Console.WriteLine(" * Row available: " + sqlDataReader.HasRows);

            while (sqlDataReader.Read())
            {
                if (sqlDataReader.GetInt32(0) == 1)
                {
                    Console.WriteLine(" * Employee Id received as sent: " + sqlDataReader.GetInt32(0));
                }
                else
                {
                    Console.WriteLine("Employee Id didn't match");
                }

                if (sqlDataReader.GetString(1) == @"Microsoft")
                {
                    Console.WriteLine(" * Employee Firstname received as sent: " + sqlDataReader.GetString(1));
                }
                else
                {
                    Console.WriteLine("Employee FirstName didn't match.");
                }

                if (sqlDataReader.GetString(2) == @"Corporation")
                {
                    Console.WriteLine(" * Employee LastName received as sent: " + sqlDataReader.GetString(2));
                }
                else
                {
                    Console.WriteLine("Employee LastName didn't match.");
                }
            }
        }

        private static void dropObjects(SqlConnection sqlConnection, string cmkName, string cekName, string tblName)
        {
            using (SqlCommand cmd = sqlConnection.CreateCommand())
            {
                cmd.CommandText = $@"IF EXISTS (select * from sys.objects where name = '{tblName}') BEGIN DROP TABLE [{tblName}] END";
                cmd.ExecuteNonQuery();
                cmd.CommandText = $@"IF EXISTS (select * from sys.column_encryption_keys where name = '{cekName}') BEGIN DROP COLUMN ENCRYPTION KEY [{cekName}] END";
                cmd.ExecuteNonQuery();
                cmd.CommandText = $@"IF EXISTS (select * from sys.column_master_keys where name = '{cmkName}') BEGIN DROP COLUMN MASTER KEY [{cmkName}] END";
                cmd.ExecuteNonQuery();
            }
        }

        private class CustomerRecord
        {
            internal int Id { get; set; }
            internal string FirstName { get; set; }
            internal string LastName { get; set; }

            public CustomerRecord(int id, string fName, string lName)
            {
                Id = id;
                FirstName = fName;
                LastName = lName;
            }
        }
    }
}

Notes

  • Pour utiliser Always Encrypted avec des enclaves sécurisées pour l’application .NET Standard, Microsoft.Data.SqlClient version 2.1.0 ou ultérieure est requis. La version de .NET Standard prise en charge est 2.1 ou une version ultérieure.

  • Pour utiliser Always Encrypted avec des enclaves sécurisées sur Linux et macOS, Microsoft.Data.SqlClient version 2.1.0 ou ultérieure est requis.

  • Pour utiliser Always Encrypted avec des enclaves VBS sans attestation, Microsoft.Data.SqlClient version 4.1.0 ou ultérieure est nécessaire.

Voir aussi