Accessing Azure Storage Tables with Access Keys

This document outlines how to use account access keys to authenticate and authorize access to your Azure Storage Tables data. Access keys provide powerful access to your storage account and should be managed securely.

Understanding Access Keys

Each Azure Storage account comes with two account access keys. These keys are essentially shared secrets that grant full access to all operations on your storage account, including:

Because of their privileged nature, it is crucial to treat these keys as you would any sensitive credential.

Retrieving Access Keys

You can retrieve your access keys through the Azure portal or programmatically using Azure SDKs or the Azure CLI.

Azure Portal

  1. Navigate to your storage account in the Azure portal.
  2. In the left-hand navigation pane, under Security + networking, select Access keys.
  3. The portal will display your two keys (key1 and key2) and their corresponding connection strings.
  4. You can click the "Show keys" button to reveal them.
  5. For security reasons, it's recommended to copy the keys and store them securely, then hide them again.

Azure CLI

You can use the following Azure CLI command to list the access keys for your storage account:

az storage account keys list --account-name  --resource-group

Replace <your-storage-account-name> and <your-resource-group-name> with your actual values.

Using Access Keys for Authentication

When interacting with Azure Storage Tables, you can use the access key in several ways:

1. Connection String

The connection string is a convenient way to package the account name and one of its access keys. It's often used in application configuration files.

DefaultEndpointsProtocol=https;AccountName=;AccountKey=;EndpointSuffix=core.windows.net

You can find the full connection strings in the Azure portal under the "Access keys" section.

2. Direct Key Usage

Many SDKs allow you to provide the account name and the access key directly.

Example (Conceptual - using a placeholder SDK method):


const { TableServiceClient } = require("@azure/data-tables");

const accountName = "";
const accountKey = "";
const tableName = "MySampleTable";

const credentials = { accountName: accountName, accountKey: accountKey };
const tableServiceClient = new TableServiceClient(`https://${accountName}.table.core.windows.net`, credentials);

async function createTable() {
    try {
        const result = await tableServiceClient.createTable(tableName);
        console.log(`Table ${tableName} created successfully.`);
    } catch (error) {
        console.error("Error creating table:", error);
    }
}

createTable();

Security Best Practices

Security Warning: Managing Access Keys

Account access keys grant full control over your storage account. Never embed them directly in client-side code (like browser JavaScript) or in public repositories. Use them judiciously and consider alternative authentication methods like Shared Access Signatures (SAS) or Azure AD authentication for more granular and secure access.

Key Rotation

It's a good security practice to periodically rotate your storage account access keys. Azure provides functionality to regenerate keys, which effectively invalidates the old ones. Ensure you update your applications and services with the new keys promptly after regeneration.

Use of Shared Access Signatures (SAS)

For scenarios where you need to grant limited access to specific resources (e.g., a single table or entity) for a limited time, consider using Shared Access Signatures (SAS). SAS tokens provide a more secure and flexible way to delegate access without sharing account keys.

Conclusion

Access keys are a fundamental method for authenticating with Azure Storage Tables. By understanding how to retrieve and use them, and by adhering to security best practices, you can effectively manage access to your storage data.