KMS Providers

Overview

Learn about the Key Management System (KMS) providers In-Use Encryption supports.

Reasons to Use a Remote Key Management System

Using a remote Key Management System to manage your Customer Master Key has the following advantages over using your local filesystem to host it:

Secure storage of the key with access auditing
Reduced risk of access permission issues
Availability and distribution of the key to remote clients
Automated key backup and recovery
Centralized encryption key lifecycle management

Additionally, for the following KMS providers, your KMS remotely encrypts and decrypts your Data Encryption Key, ensuring your Customer Master Key is never exposed to your Queryable Encryption or CSFLE enabled application:

Amazon Web Services KMS
Azure Key Vault
Google Cloud KMS

Key Management System Tasks

In In-Use Encryption, your Key Management System:

Creates and encrypts the Customer Master Key
Encrypts the Data Encryption Keys created by your application
Decrypts Data Encryption Keys

To learn more about Customer Master Keys and Data Encryption Keys, see Encryption Keys and Key Vaults.

Create and Store your Customer Master Key

To create a Customer Master Key, configure your Key Management System to generate your Customer Master Key as follows:

To view a tutorial that demonstrates how to create and store a CMK in your preferred KMS, see the Queryable Encryption Automatic Encryption Tutorial or CSFLE Automatic Encryption Tutorial.

Create and Encrypt a Data Encryption Key

To create a Data Encryption Key:

Instantiate a ClientEncryption instance in your Queryable Encryption or CSFLE enabled application:
- Provide a kmsProviders object that specifies the credentials your application uses to authenticate with your KMS provider.
Create a Data Encryption Key with the CreateDataKey method of the ClientEncryption object in your application.
- Provide a dataKeyOpts object that specifies with which key your KMS should encrypt your new Data Encryption Key.

To view a tutorial demonstrating how to create and encrypt a Data Encryption Key, see the following resources:

To view the structure of kmsProviders and dataKeyOpts objects for all supported KMS providers, see Supported Key Management Services.

Supported Key Management Services

The following sections of this page present the following information for all Key Management System providers:

Architecture of In-Use Encryption enabled client
Structure of kmsProviders objects
Structure of dataKeyOpts objects

Both Queryable Encryption and CSFLE support the following Key Management System providers:

Amazon Web Services KMS

This section provides information related to using AWS Key Management Service in your Queryable Encryption or CSFLE enabled application.

To view a tutorial demonstrating how to use AWS KMS in your application, see Overview: Enable Queryable Encryption or Use Automatic Client-Side Field Level Encryption with AWS.

Architecture

The following diagram describes the architecture of a Queryable Encryption enabled application using AWS KMS.

Note

Client Can't Access Customer Master Key

When using the preceding Key Management System, your Queryable Encryption enabled application does not have access to your Customer Master Key.

kmsProviders Object

The following table presents the structure of a kmsProviders object for AWS KMS:

Field	Required for IAM User	Required for IAM Role	Description
Access Key ID	Yes	Yes	Identifies the account user.
Secret Access Key	Yes	Yes	Contains the authentication credentials of the account user.
Session Token	No	Yes	Contains a token obtained from AWS Security Token Service (STS).

dataKeyOpts Object

The following table presents the structure of a dataKeyOpts object for AWS KMS:

Field	Required	Description
key	Yes	Amazon Resource Number (ARN) of the master key.
region	No	AWS region of your master key, e.g. "us-west-2"; required only if not specified in your ARN.
endpoint	No	Custom hostname for the AWS endpoint if configured for your account.

Azure Key Vault

This section provides information related to using Azure Key Vault in your Queryable Encryption or CSFLE enabled application.

To view a tutorial demonstrating how to use Azure Key Vault in your application, see Overview: Enable Queryable Encryption or Use Automatic Client-Side Field Level Encryption with Azure.

Architecture

The following diagram describes the architecture of a Queryable Encryption enabled application using Azure Key Vault.

Note

Client Can't Access Customer Master Key

When using the preceding Key Management System, your Queryable Encryption enabled application does not have access to your Customer Master Key.

kmsProviders Object

The following table presents the structure of a kmsProviders object for Azure Key Vault:

Field	Required	Description
azure.tenantId	Yes	Identifies the organization of the account.
azure.clientId	Yes	Identifies the clientId to authenticate your registered application.
azure.clientSecret	Yes	Used to authenticate your registered application.
azure.identityPlatformEndpoint	No	Specifies a hostname and port number for the authentication server. Defaults to login.microsoftonline.com and is only needed for non-commercial Azure instances such as a government or China account.

dataKeyOpts Object

The following table presents the structure of a dataKeyOpts object for Azure Key Vault:

Field	Required	Description
keyName	Yes	Name of the master key
keyVersion	No, but strongly recommended	Version of the master key
keyVaultEndpoint	Yes	URL of the key vault. E.g. myVaultName.vault.azure.net

Warning

If you do not include a keyVersion field, Azure Key Vault attempts to decrypt Data Encryption Keys using the latest Customer Master Key. If you rotate the CMK but do not rewrap the Data Encryption Keys with the new master key, attempting to decrypt an existing DEK fails, since the DEK is encrypted with the previous version of the CMK.

Google Cloud Platform KMS

This section provides information related to using Google Cloud Key Management in your Queryable Encryption or CSFLE enabled application.

To view a tutorial demonstrating how to use GCP KMS in your application, see Overview: Enable Queryable Encryption or Use Automatic Client-Side Field Level Encryption with GCP.

Architecture

The following diagram describes the architecture of a Queryable Encryption enabled application using GCP KMS.

Note

Client Can't Access Customer Master Key

When using the preceding Key Management System, your Queryable Encryption enabled application does not have access to your Customer Master Key.

kmsProviders Object

The following table presents the structure of a kmsProviders object for GCP KMS:

Field

Required

Description

Yes

Identifies your service account email address.

privateKey

Yes

Identifies your service account private key in either
base64 string or
Binary subtype 0
format without the prefix and suffix markers.

Suppose your service account private key value is as follows:

-----BEGIN PRIVATE KEY-----\nyour-private-key\n-----END PRIVATE KEY-----\n

The value you would specify for this field is:

your-private-key

If you have a user-key.json credential file, you can extract the string by executing the following command in a bash or similar shell. The following command requires that you install OpenSSL :

cat user-key.json | jq -r .private_key | openssl pkcs8 -topk8 -nocrypt -inform PEM -outform DER | base64 -w 0

endpoint

Specifies a hostname and port number for the authentication server. Defaults to oauth2.googleapis.com.

dataKeyOpts Object

The following table presents the structure of a dataKeyOpts object for GCP KMS:

Field	Required	Description
projectId	Yes	Identifier for your project in which you created the key.
location	Yes	Region specified for your key.
keyRing	Yes	Identifier for the group of keys your key belongs to.
keyName	Yes	Identifier for the symmetric master key.
keyVersion	No	Specifies the version of the named key. If not specified, the default version of the key is used.
endpoint	No	Specifies the host and optional port of the Cloud KMS. The default is `cloudkms.googleapis.com`.

KMIP

This section provides information related to using a KMIP compliant Key Management System in your Queryable Encryption or CSFLE enabled application.

To learn how to set up KMIP with HashiCorp Vault, see the How to Set Up HashiCorp Vault KMIP Secrets Engine with MongoDB CSFLE or Queryable Encryption blog post.

Architecture

The following diagram describes the architecture of a Queryable Encryption enabled application using a KMIP-compliant key provider.

Important

Client Accesses Customer Master Key

When your Queryable Encryption enabled application uses a KMIP-compliant key provider without specifying the delegated option, your application directly accesses your Customer Master Key. To avoid directly accessing your CMK, you can set the delegated option to true in your dataKeyOpts object.

kmsProviders Object

The following table presents the structure of a kmsProviders object for a KMIP compliant Key Management System:

Note

Authenticate through TLS/SSL

Your Queryable Encryption enabled application authenticates through TLS/SSL when using KMIP.

Field	Required	Description
endpoint	Yes	Specifies a hostname and port number for the authentication server.

dataKeyOpts Object

The following table presents the structure of a dataKeyOpts object for a KMIP compliant Key Management System:

Field	Required	Description
keyId	No	The `keyId` field of a 96 byte Secret Data managed object stored in your KMIP-compliant key provider. If you do not specify the `keyId` field in the `masterKey` document you send to your KMIP-compliant key provider, the driver creates a new 96 Byte Secret Data managed object in your KMIP-compliant key provider to act as your master key.
endpoint	Yes	The URI of your KMIP-compliant key provider.
delegated	No	Set this option to `true` to delegate the encryption and decryption of your DEK to your KMIP-compliant key provider. Delegating these to the KMIP-compliant key provider ensures that you never have direct access to the CMK. If you do not set the `delegated` option to `true`, your application directly accesses and transports your Customer Master Key from the KMIP provider. IMPORTANT: The `delegated` option is not available in the Ruby or Go drivers.

Local Key Provider

This section provides information related to using a Local Key Provider in your Queryable Encryption or CSFLE enabled application.

Warning

Secure your Local Key File in Production

We recommend storing your Customer Master Keys in a remote Key Management System (KMS). To learn how to use a remote KMS in your Queryable Encryption implementation, see the Queryable Encryption Tutorials guide.

If you choose to use a local key provider in production, exercise great caution and do not store it on the file system. Consider injecting the key into your client application using a sidecar process, or use another approach that keeps the key secure.

To view a tutorial demonstrating how to use a Local Key Provider for testing Queryable Encryption, see the Queryable Encryption Quick Start or CSFLE Quick Start.

Architecture

When you use a Local Key Provider for testing, your application retrieves your Customer Master Key from the computer it runs on. To use a Local Key Provider in production, use an approach that doesn't store the key on the file system. For example, you can inject the key into the client process via a sidecar.

The following diagram describes the architecture of a Queryable Encryption-enabled application using a Local Key Provider.

Local Key Provider architecture diagram.

kmsProviders Object

The following table presents the structure of a kmsProviders object for a Local Key Provider:

Field	Required	Description
key	Yes	The master key used to encrypt/decrypt data keys. The master key is passed as a base64 encoded string.

dataKeyOpts Object

When you use a Local Key Provider, you specify your Customer Master Key through your kmsProviders object.