Working with keys - AWS Key Management Service

Working with keys

The examples in this topic use the AWS KMS API to create, view, enable, and disable AWS KMS customer master keys (CMKs), and to generate data keys.

Creating a customer master key

To create a customer master key (CMK), use the CreateKey operation. The examples in this section create a symmetric CMK. The Description parameter used in these examples is optional.

In languages that require a client object, these examples use the AWS KMS client object that you created in Creating a client.

For help with creating CMKs in the AWS KMS console, see Creating keys.

Java

For details, see the createKey method in the AWS SDK for Java API Reference.

// Create a CMK // String desc = "Key for protecting critical data"; CreateKeyRequest req = new CreateKeyRequest().withDescription(desc); CreateKeyResult result = kmsClient.createKey(req);
C#

For details, see the CreateKey method in the AWS SDK for .NET.

// Create a CMK // String desc = "Key for protecting critical data"; CreateKeyRequest req = new CreateKeyRequest() { Description = desc }; CreateKeyResponse response = kmsClient.CreateKey(req);
Python

For details, see the create_key method in the AWS SDK for Python (Boto3).

# Create a CMK desc = 'Key for protecting critical data' response = kms_client.create_key( Description=desc )
Ruby

For details, see the create_key instance method in the AWS SDK for Ruby.

# Create a CMK desc = 'Key for protecting critical data' response = kmsClient.create_key({ description: desc })
PHP

For details, see the CreateKey method in the AWS SDK for PHP.

// Create a CMK // $desc = "Key for protecting critical data"; $result = $KmsClient->createKey([ 'Description' => $desc ]);
Node.js

For details, see the createKey property in the AWS SDK for JavaScript in Node.js.

// Create a CMK // const Description = 'Key for protecting critical data'; kmsClient.createKey({ Description }, (err, data) => { ... });
PowerShell

To create a CMK in PowerShell, use the New-KmsKey cmdlet.

# Create a CMK $desc = 'Key for protecting critical data' New-KmsKey -Description $desc

To use the AWS KMS PowerShell cmdlets, install the AWS.Tools.KeyManagementService module. For more information, see the AWS Tools for Windows PowerShell User Guide.

Generating a data key

To generate a symmetric data key, use the GenerateDataKey operation. This operation takes a symmetric CMK and returns a plaintext data key and a copy of that data key encrypted under the CMK that you specified. You must specify either a KeySpec or NumberOfBytes (but not both) in each command.

In languages that require a client object, these examples use the AWS KMS client object that you created in Creating a client.

Java

For details, see the generateDataKey method in the AWS SDK for Java API Reference.

// Generate a data key // // Replace the following example key ARN with any valid key identfier String keyId = "arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab"; GenerateDataKeyRequest dataKeyRequest = new GenerateDataKeyRequest(); dataKeyRequest.setKeyId(keyId); dataKeyRequest.setKeySpec("AES_256"); GenerateDataKeyResult dataKeyResult = kmsClient.generateDataKey(dataKeyRequest); ByteBuffer plaintextKey = dataKeyResult.getPlaintext(); ByteBuffer encryptedKey = dataKeyResult.getCiphertextBlob();
C#

For details, see the GenerateDataKey method in the AWS SDK for .NET.

// Generate a data key // // Replace the following example key ARN with any valid key identfier String keyId = "arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab"; GenerateDataKeyRequest dataKeyRequest = new GenerateDataKeyRequest() { KeyId = keyId, KeySpec = DataKeySpec.AES_256 }; GenerateDataKeyResponse dataKeyResponse = kmsClient.GenerateDataKey(dataKeyRequest); MemoryStream plaintextKey = dataKeyResponse.Plaintext; MemoryStream encryptedKey = dataKeyResponse.CiphertextBlob;
Python

For details, see the generate_data_key method in the AWS SDK for Python (Boto3).

# Generate a data key # Replace the following example key ARN with any valid key identfier key_id = 'arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab' response = kms_client.generate_data_key( KeyId=key_id, KeySpec='AES_256' ) plaintext_key = response['Plaintext'] encrypted_key = response['CiphertextBlob']
Ruby

For details, see the generate_data_key instance method in the AWS SDK for Ruby.

# Generate a data key # Replace the following example key ARN with any valid key identfier key_id = 'arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab' response = kmsClient.generate_data_key({ key_id: key_id, key_spec: 'AES_256' }) plaintext_key = response.plaintext encrypted_key = response.ciphertext_blob
PHP

For details, see the GenerateDataKey method in the AWS SDK for PHP.

// Generate a data key // // Replace the following example key ARN with any valid key identfier $keyId = 'arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab'; $keySpec = 'AES_256'; $result = $KmsClient->generateDataKey([ 'KeyId' => $keyId, 'KeySpec' => $keySpec, ]); $plaintextKey = $result['Plaintext']; $encryptedKey = $result['CiphertextBlob'];
Node.js

For details, see the generateDataKey property in the AWS SDK for JavaScript in Node.js.

// Generate a data key // // Replace the following example key ARN with any valid key identfier const KeyId = 'arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab'; const KeySpec = 'AES_256'; kmsClient.generateDataKey({ KeyId, KeySpec }, (err, data) => { if (err) console.log(err, err.stack); else { const { CiphertextBlob, Plaintext } = data; ... } });
PowerShell

To generate a symmetric data key, use the New-KMSDataKey cmdlet.

In the output, the plaintext key (in the Plaintext property) and the encrypted key (in the CiphertextBlob property) are MemoryStream objects. To convert them to strings, use the methods of the MemoryStream class, or a cmdlet or function that converts MemoryStream objects to strings, such as the ConvertFrom-MemoryStream and ConvertFrom-Base64 functions in the Convert module.

# Generate a data key # Replace the following example key ARN with any valid key identfier $keyId = 'arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab' $keySpec = 'AES_256' $response = New-KmsDataKey -KeyId $keyId -KeySpec $keySpec $plaintextKey = $response.Plaintext $encryptedKey = $response.CiphertextBlob

To use the AWS KMS PowerShell cmdlets, install the AWS.Tools.KeyManagementService module. For more information, see the AWS Tools for Windows PowerShell User Guide.

Viewing a customer master key

To get detailed information about a customer master key (CMK), including the CMK ARN and key state, use the DescribeKey operation.

DescribeKey does not get aliases. To get aliases, use the ListAliases operation. For examples, see Working with aliases.

In languages that require a client object, these examples use the AWS KMS client object that you created in Creating a client.

For help with viewing CMKs in the AWS KMS console, see Viewing keys.

Java

For details, see the describeKey method in the AWS SDK for Java API Reference.

// Describe a CMK // // Replace the following example key ARN with any valid key identfier String keyId = "arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab"; DescribeKeyRequest req = new DescribeKeyRequest().withKeyId(keyId); DescribeKeyResult result = kmsClient.describeKey(req);
C#

For details, see the DescribeKey method in the AWS SDK for .NET.

// Describe a CMK // // Replace the following example key ARN with any valid key identfier String keyId = "arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab"; DescribeKeyRequest describeKeyRequest = new DescribeKeyRequest() { KeyId = keyId }; DescribeKeyResponse describeKeyResponse = kmsClient.DescribeKey(describeKeyRequest);
Python

For details, see the describe_key method in the AWS SDK for Python (Boto3).

# Describe a CMK # Replace the following example key ARN with any valid key identfier key_id = 'arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab' response = kms_client.describe_key( KeyId=key_id )
Ruby

For details, see the describe_key instance method in the AWS SDK for Ruby.

# Describe a CMK # Replace the following example key ARN with any valid key identfier key_id = 'arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab' response = kmsClient.describe_key({ key_id: key_id })
PHP

For details, see the DescribeKey method in the AWS SDK for PHP.

// Describe a CMK // // Replace the following example key ARN with any valid key identfier $keyId = 'arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab'; $result = $KmsClient->describeKey([ 'KeyId' => $keyId, ]);
Node.js

For details, see the describeKey property in the AWS SDK for JavaScript in Node.js.

// Describe a CMK // // Replace the following example key ARN with any valid key identfier const KeyId = 'arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab'; kmsClient.describeKey({ KeyId }, (err, data) => { ... });
PowerShell

To get detailed information about a CMK, use the Get-KmsKey cmdlet.

# Describe a CMK # Replace the following example key ARN with any valid key identfier $keyId = 'arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab' Get-KmsKey -KeyId $keyId

To use the AWS KMS PowerShell cmdlets, install the AWS.Tools.KeyManagementService module. For more information, see the AWS Tools for Windows PowerShell User Guide.

Getting key IDs and key ARNs of CMKs

To get the key IDs and key ARNs of the customer master keys, use the ListKeys operation. These examples use the optional Limit parameter, which sets the maximum number of CMKs returned in each call. For help identifying a CMK in an AWS KMS operations, see Key identifiers (KeyId).

In languages that require a client object, these examples use the AWS KMS client object that you created in Creating a client.

For help with finding key IDs and key ARNs in the AWS KMS console, see Finding the key ID and ARN.

Java

For details, see the listKeys method in the AWS SDK for Java API Reference.

// List CMKs in this account // Integer limit = 10; ListKeysRequest req = new ListKeysRequest().withLimit(limit); ListKeysResult result = kmsClient.listKeys(req);
C#

For details, see the ListKeys method in the AWS SDK for .NET.

// List CMKs in this account // int limit = 10; ListKeysRequest listKeysRequest = new ListKeysRequest() { Limit = limit }; ListKeysResponse listKeysResponse = kmsClient.ListKeys(listKeysRequest);
Python

For details, see the list_keys method in the AWS SDK for Python (Boto3).

# List CMKs in this account response = kms_client.list_keys( Limit=10 )
Ruby

For details, see the list_keys instance method in the AWS SDK for Ruby.

# List CMKS in this account response = kmsClient.list_keys({ limit: 10 })
PHP

For details, see the ListKeys method in the AWS SDK for PHP.

// List CMKs in this account // $limit = 10; $result = $KmsClient->listKeys([ 'Limit' => $limit, ]);
Node.js

For details, see the listKeys property in the AWS SDK for JavaScript in Node.js.

// List CMKs in this account // const Limit = 10; kmsClient.listKeys({ Limit }, (err, data) => { ... });
PowerShell

To get the key ID and key ARN of all CMKs in the account and Region, use the Get-KmsKeyList cmdlet.

To limit the number of output objects, this example uses the Select-Object cmdlet, instead of the Limit parameter, which is being deprecated in list cmdlets. For help with paginating output in AWS Tools for PowerShell, see Output Pagination with AWS Tools for PowerShell.

# List CMKs in this account $limit = 10 Get-KmsKeyList | Select-Object -First $limit

To use the AWS KMS PowerShell cmdlets, install the AWS.Tools.KeyManagementService module. For more information, see the AWS Tools for Windows PowerShell User Guide.

Enabling customer master keys

To enable a disabled customer master key (CMK), use the EnableKey operation.

In languages that require a client object, these examples use the AWS KMS client object that you created in Creating a client.

For help with enabling and disabling CMKs in the AWS KMS console, see Enabling and disabling keys.

Java

For details about the Java implementation, see the enableKey method in the AWS SDK for Java API Reference.

// Enable a CMK // // Replace the following example key ARN with a valid key ID or key ARN String keyId = "arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab"; EnableKeyRequest req = new EnableKeyRequest().withKeyId(keyId); kmsClient.enableKey(req);
C#

For details, see the EnableKey method in the AWS SDK for .NET.

// Enable a CMK // // Replace the following example key ARN with a valid key ID or key ARN String keyId = "arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab"; EnableKeyRequest enableKeyRequest = new EnableKeyRequest() { KeyId = keyId }; kmsClient.EnableKey(enableKeyRequest);
Python

For details, see the enable_key method in the AWS SDK for Python (Boto3).

# Enable a CMK # Replace the following example key ARN with a valid key ID or key ARN key_id = 'arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab' response = kms_client.enable_key( KeyId=key_id )
Ruby

For details, see the enable_key instance method in the AWS SDK for Ruby.

# Enable a CMK # Replace the following example key ARN with a valid key ID or key ARN key_id = 'arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab' response = kmsClient.enable_key({ key_id: key_id })
PHP

For details, see the EnableKey method in the AWS SDK for PHP.

// Enable a CMK // // Replace the following example key ARN with a valid key ID or key ARN $keyId = 'arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab'; $result = $KmsClient->enableKey([ 'KeyId' => $keyId, ]);
Node.js

For details, see the enableKey property in the AWS SDK for JavaScript in Node.js.

// Enable a CMK // // Replace the following example key ARN with a valid key ID or key ARN const KeyId = 'arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab'; kmsClient.enableKey({ KeyId }, (err, data) => { ... });
PowerShell

To enable a CMK, use the Enable-KmsKey cmdlet.

# Enable a CMK # Replace the following example key ARN with a valid key ID or key ARN $keyId = 'arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab' Enable-KmsKey -KeyId $keyId

To use the AWS KMS PowerShell cmdlets, install the AWS.Tools.KeyManagementService module. For more information, see the AWS Tools for Windows PowerShell User Guide.

Disabling customer master keys

To disable a CMK, use the DisableKey operation. Disabling a CMK prevents it from being used in cryptographic operations.

In languages that require a client object, these examples use the AWS KMS client object that you created in Creating a client.

For help with enabling and disabling CMKs in the AWS KMS console, see Enabling and disabling keys.

Java

For details, see the disableKey method in the AWS SDK for Java API Reference.

// Disable a CMK // // Replace the following example key ARN with a valid key ID or key ARN String keyId = "arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab"; DisableKeyRequest req = new DisableKeyRequest().withKeyId(keyId); kmsClient.disableKey(req);
C#

For details, see the DisableKey method in the AWS SDK for .NET.

// Disable a CMK // // Replace the following example key ARN with a valid key ID or key ARN String keyId = "arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab"; DisableKeyRequest disableKeyRequest = new DisableKeyRequest() { KeyId = keyId }; kmsClient.DisableKey(disableKeyRequest);
Python

For details, see the disable_key method in the AWS SDK for Python (Boto3).

# Disable a CMK # Replace the following example key ARN with a valid key ID or key ARN key_id = 'arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab' response = kms_client.disable_key( KeyId=key_id )
Ruby

For details, see the disable_key instance method in the AWS SDK for Ruby.

# Disable a CMK # Replace the following example key ARN with a valid key ID or key ARN key_id = 'arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab' response = kmsClient.disable_key({ key_id: key_id })
PHP

For details, see the DisableKey method in the AWS SDK for PHP.

// Disable a CMK // // Replace the following example key ARN with a valid key ID or key ARN $keyId = 'arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab'; $result = $KmsClient->disableKey([ 'KeyId' => $keyId, ]);
Node.js

For details, see the disableKey property in the AWS SDK for JavaScript in Node.js.

// Disable a CMK // // Replace the following example key ARN with a valid key ID or key ARN const KeyId = 'arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab'; kmsClient.disableKey({ KeyId }, (err, data) => { ... });
PowerShell

To disable a CMK, use the Disable-KmsKey cmdlet.

# Disable a CMK # Replace the following example key ARN with a valid key ID or key ARN $keyId = 'arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab' Disable-KmsKey -KeyId $keyId

To use the AWS KMS PowerShell cmdlets, install the AWS.Tools.KeyManagementService module. For more information, see the AWS Tools for Windows PowerShell User Guide.