Database Manual / Reference / mongosh Methods / In-Use Encryption

ClientEncryption.decrypt() (mongosh method)

ClientEncryption.decrypt(encryptedValue)

ClientEncryption.decrypt() decrypts the encryptionValue if the current database connection was configured with access to the Key Management Service (KMS) and key vault used to encrypt encryptionValue.

Returns:	The decrypted value.

Compatibility

This command is available in deployments hosted in the following environments:

MongoDB Atlas: The fully managed service for MongoDB deployments in the cloud

MongoDB Enterprise: The subscription-based, self-managed version of MongoDB
MongoDB Community: The source-available, free-to-use, and self-managed version of MongoDB

Syntax

ClientEncryption.decrypt has the following syntax:

clientEncryption = db.getMongo().getClientEncryption()

clientEncryption.decrypt(encryptedValue)

The encryptedValue must be a binary data object with subtype 6 created using client-side field level encryption.

Behavior

Read operations issued from a database connection configured with access to the correct Key Management Service (KMS) and Key Vault can automatically decrypt field values encrypted using ClientEncryption.encrypt(). Clients only need to use decrypt() to decrypt Binary subtype 6 values not stored within a document field.

Enable Client-Side Field Level Encryption on Database Connection

The mongosh ClientEncryption methods require a database connection with in-use encryption enabled. If the current database connection was not initiated with in-use encryption enabled, either:

Use the Mongo() constructor from the mongosh to establish a connection with the required in-use encryption options. The Mongo() method supports the following Key Management Service (KMS) providers for Customer Master Key (CMK) management:
or
Use the mongosh command line options to establish a connection with the required options. The command line options only support the Amazon Web Services KMS provider for CMK management.

Example

The following example uses a locally managed KMS for the client-side field level encryption configuration.

Create Your Encrypted Connection

Start mongosh

Run:
```
mongosh --nodb
```
--nodb means don't connect to a database.

Generate a Key String

Generate a base 64 96-byte string:

const TEST_LOCAL_KEY = require("crypto").randomBytes(96).toString("base64")

Create an Encryption Options Object

To create a client-side field level encryption options object, use the TEST_LOCAL_KEY string from the previous step:

   var autoEncryptionOpts = {
      "keyVaultNamespace" : "encryption.__dataKeys",
      "kmsProviders" : {
         "local" : {
            "key" : BinData(0, TEST_LOCAL_KEY)
         }
      }
   }

Create an Encrypted Client Object

To create an encrypted client object, use the Mongo() constructor. Replace the mongodb://myMongo.example.net URI with the connection string URI for the target cluster. For example:
```
encryptedClient = Mongo(
   "mongodb://myMongo.example.net:27017/?replSetName=myMongo",
   autoEncryptionOpts
)
```

Decrypt Your Data

Retrieve the ClientEncryption object and use the ClientEncryption.decrypt() method to decrypt a value encrypted by ClientEncryption.encrypt().

clientEncryption = encryptedClient.getClientEncryption();

clientEncryption.decrypt(BinData(6,"AmTi2H3xaEk8u9+jlFNaLLkC3Q/+kmwDbbWrq+h9nuv9W+u7A5a0UnpULBNZH+Q21fAztPpU09wpKPrju9dKfpN1Afpj1/ZhFcH6LYZOWSBBOAuUNjPLxMNSYOOuITuuYWo="))

Example Results

If successful, decrypt() returns the decrypted value:

"123-45-6789"

Learn More

For complete documentation on initiating MongoDB connections with client-side field level encryption enabled, see Mongo().

Back

ClientEncryption.encryptExpression

getClientEncryption