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ClientEncryption.decrypt()

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New in version 4.2.

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.

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 client-side field level encryption methods require a database connection with client-side field level encryption enabled. If the current database connection was not initiated with client-side field level encryption enabled, either:

Example

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

1

Create Your Encrypted Connection

1

Start mongosh

Start the mongosh client.

mongosh --nodb
2

Generate Your Key

To configure client-side field level encryption for a locally managed key, generate a base64-encoded 96-byte string with no line breaks.

const TEST_LOCAL_KEY = require("crypto").randomBytes(96).toString("base64")
3

Create the Client-Side Field Level Encryption Options

Create the client-side field level encryption options using the generated local key string:

 var autoEncryptionOpts = {
   "keyVaultNamespace" : "encryption.__dataKeys",
   "kmsProviders" : {
     "local" : {
       "key" : BinData(0, TEST_LOCAL_KEY)
     }
   }
 }
4

Create Your Encrypted Client

Use the Mongo() constructor with the client-side field level encryption options configured to create a database connection. Replace the mongodb://myMongo.example.net URI with the connection string URI of the target cluster.

encryptedClient = Mongo(
  "mongodb://myMongo.example.net:27017/?replSetName=myMongo",
   autoEncryptionOpts
)
2

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().