Always Encrypted: Securing Your SQL Server Data for the Future

Introduction

In today’s digital landscape, data security is a top priority for businesses and organizations of all sizes. With the rise of cyber threats and data breaches, it’s crucial to implement robust security measures to protect sensitive information. One of the most effective ways to achieve this is through database encryption.

SQL Server Always Encrypted is a powerful feature in Microsoft’s SQL Server that provides enhanced security for sensitive data stored in databases. In this blog, we’ll dive deep into the background of Always Encrypted, the challenges and opportunities it presents, best practices for implementation, future outlook, and more.

Background

Database encryption has been around for decades, but it has traditionally been a complex and challenging process to implement. Older encryption techniques require complex key management and can impact performance. Moreover, encryption is typically applied at the server level, making it vulnerable to insider attacks or unauthorized access by administrators.

SQL Server Always Encrypted was introduced in SQL Server 2016 as a response to these challenges. Always Encrypted uses client-side encryption to protect sensitive data stored in databases. With client-side encryption, data is encrypted on the client side before being sent to the server, so the server doesn’t have access to the unencrypted data.

Challenges and Opportunities

One of the most significant challenges of database encryption is balancing security with performance. Encryption can cause a significant impact on database performance, especially when dealing with large volumes of data. Always Encrypted addresses this challenge by using client-side encryption, which ensures that encryption and decryption are handled by the client, not the server.

Always Encrypted also presents a unique opportunity for businesses and organizations to secure sensitive data in a way that was previously difficult or impossible to achieve. For example, in the healthcare industry, Always Encrypted can be used to protect patient data stored in electronic health records (EHRs). Similarly, in the financial industry, Always Encrypted can be used to secure sensitive financial data such as credit card numbers, social security numbers, and bank account information.

Best Practices

Implementing Always Encrypted in SQL Server requires careful planning and execution. Here are some best practices to keep in mind:

Use the latest version of SQL Server: Always Encrypted was first introduced in SQL Server 2016, and subsequent versions have improved on the feature. Always use the latest version of SQL Server to take advantage of the latest security enhancements.

Use column-level encryption: Always Encrypted allows for column-level encryption, which means you can selectively encrypt only the columns that contain sensitive data. This reduces the performance impact of encryption and makes it easier to manage encrypted data.

Use a key management system: Always Encrypted relies on key management to encrypt and decrypt data. Use a key management system to securely store and manage encryption keys.

Test performance before deployment: Always Encrypted can impact database performance, especially when dealing with large volumes of data. Before deploying Always Encrypted, test its performance in a test environment to ensure it won’t cause issues in production.

Future Outlook

As cyber threats continue to evolve, the need for advanced database encryption techniques like Always Encrypted will only increase. Microsoft is continually working to enhance the security features of SQL Server, and Always Encrypted is no exception. In the future, we can expect to see more enhancements to Always Encrypted, such as support for additional encryption algorithms and key management systems.

Conclusion

SQL Server Always Encrypted is a powerful feature that provides enhanced security for sensitive data stored in databases. With client-side encryption, data is encrypted before being sent to the server, ensuring that the server never has access to the unencrypted data. Implementing Always Encrypted requires careful planning and execution, but it provides significant benefits in terms of data security. SQL Server Always Encrypted is an essential feature for organizations that need to protect sensitive data stored in their SQL Server databases. While there are challenges to implementing the feature, following best practices and ensuring compatibility with all applications and tools can help organizations successfully implement SQL Server Always Encrypted and improve their data security.

Thank You,
Vivek Janakiraman

Disclaimer:
The views expressed on this blog are mine alone and do not reflect the views of my company or anyone else. All postings on this blog are provided “AS IS” with no warranties, and confers no rights.

Connect to SQL Server with PowerShell and Azure key Vault

-> Requirement will be to query an Azure SQL Database via PowerShell and display the results. We will not list the SQL Server Instance, Username and password as clear text in PowerShell script, instead we use the secret from Azure Key Vault to achieve this.

Create an Azure SQL Database

-> Complete tabs “Networking”, “Security”, “Additional settings” and “Tags” as appropriate.

Create an Azure Key Vault

-> Complete tabs “Access policy”, “Networking” and “Tags” as appropriate.

-> Get into Azure Key Vault “sqlcon-key-vault-eastus”. Click on “Secrets” and then “Generate/Import”,

-> Value as mentioned in above screenshot is as below,

Server=tcp:jbdw.database.windows.net,1433;Initial Catalog=prod-jbsqldb01;Persist Security Info=False;User ID=<username>;Password=<Password>;MultipleActiveResultSets=False;Encrypt=True;TrustServerCertificate=False;Connection Timeout=30;

-> Click Create.

Get the required Data using PowerShell

##Script to display database names available## 
## Version 1.0 
##Author : Vivek Janakiraman## 
##cls ##Clearing Screen 

Connect-AzAccount

##Key in the correct Subscription below##
Set-AzContext -Subscription "00000000-0000-0000-0000-000000000000"

$keyvault = "sqlcon-key-vault-eastus" ##Provide the Azure key Vault name##
$ConnectionString = "prod-jbsqldb01-connection-string" ##Provide the the name of the secret created within Azure key Vault##


$Vault = get-azkeyvault -VaultName $keyvault
$Secret = get-azkeyvaultsecret -Name $ConnectionString -VaultName $keyvault
$SecretValue = $Secret.SecretValue 
$ConnectionString = [System.Runtime.InteropServices.Marshal]::PtrToStringAuto([System.Runtime.InteropServices.Marshal]::SecureStringToBSTR($SecretValue))

$tsqlcommand = "select name from sys.databases"; 

#SQL Connection - connection to SQL server 
$sqlConnection = new-object System.Data.SqlClient.SqlConnection; 
$sqlConnection.ConnectionString = $connectionString; 

#SQL Command - set up the SQL call 
$sqlCommand = New-Object System.Data.SqlClient.SqlCommand; 
$sqlCommand.Connection = $sqlConnection; 
$sqlCommand.CommandText = $tsqlcommand; 

#SQL Adapter - get the results using the SQL Command 
$sqlAdapter = new-object System.Data.SqlClient.SqlDataAdapter 
$sqlAdapter.SelectCommand = $sqlCommand 
$dataSet = new-object System.Data.Dataset 
$recordCount = $sqlAdapter.Fill($dataSet) 

#Close SQL Connection 
$sqlConnection.Close(); 

#Get single table from dataset 
$data = $dataSet.Tables[0] 
$data

-> Below is the output,

-> There is a possibility of below error while executing the script,

Exception calling "SecureStringToBSTR" with "1" argument(s): "Value cannot be null.
Parameter name: s"
At C:\temp\Connection_Template_Working.ps1:16 char:1
+ $ConnectionString = [System.Runtime.InteropServices.Marshal]::PtrToSt ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (:) [], MethodInvocationException
    + FullyQualifiedErrorId : ArgumentNullException
 
Exception setting "ConnectionString": "Format of the initialization string does not conform to specification starting at index 0."
At C:\temp\Connection_Template_Working.ps1:22 char:1
+ $sqlConnection.ConnectionString = $connectionString;
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (:) [], SetValueInvocationException
    + FullyQualifiedErrorId : ExceptionWhenSetting
 
Exception calling "Fill" with "1" argument(s): "The ConnectionString property has not been initialized."
At C:\temp\Connection_Template_Working.ps1:33 char:1
+ $recordCount = $sqlAdapter.Fill($dataSet)
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (:) [], MethodInvocationException
    + FullyQualifiedErrorId : InvalidOperationException

Exception calling “SecureStringToBSTR” with “1” argument(s): “Value cannot be null.

-> This error occurs when parameter $ConnectionString is wrong. It should be same as what is seen in below screenshot in Azure key Vault,

Thank You,
Vivek Janakiraman

Disclaimer:
The views expressed on this blog are mine alone and do not reflect the views of my company or anyone else. All postings on this blog are provided “AS IS” with no warranties, and confers no rights.