getClientEncryption()

New in version 4.2.

beta

Client-Side Field Level Encryption is available as a beta. The contentsof this page may change during the beta period.

• getClientEncryption()
• Returns the ClientEncryption object for the current database collection.The ClientEncryption object supports explicit (manual) encryptionand decryption of field values forClient-Side field level encryption.

getClientEncryption() has the following syntax:

db.getMongo().getClientEncryption();

Use the ClientEncryption object to access the followingexplicit encryption methods:

• encrypt()
• decrypt()

Behavior

Enable Client-Side Field Level Encryption on Database Connection

The mongo client-side field level encrytion methodsrequire a database connection with client-side field level encryptionenabled. If the current database connection was not initiated withclient-side field level encryption enabled, either:

• Use the Mongo() constructor from the mongoshell to establish a connection with the required client-side fieldlevel encryption options. The Mongo() method supports bothAmazon Web Services and Local Key Management Service (KMS) providersfor Customer Master Key (CMK) management.

or

• Use the mongo shell command line options to establish aconnection with the required options. The command line options onlysupport the AWS KMS provider for CMK management.

Example

The getKeyVault() method automatically creates aunique index on the keyAltNames fieldwith a partial index filter for onlydocuments where keyAltNames exists. getKeyVault()creates this index in the key vault collection. This prevents any twodata encryption keys in the same key vault from having the same keyalternative name and therefore avoids ambiguity around which dataencryption key is appropriate for encryption/decryption.

Warning

Do not drop the unique index created by getKeyVault().Client-side field level encryption operations depend onserver-enforced uniqueness of keyAltNames. Removing the indexmay lead to unexpected or unpredictable behavior.

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

Configuring client-side field level encryption for a locallymanaged key requires specifying a base64-encoded 96-bytestring with no line breaks. The following operation generatesa key that meets the stated requirements and loads it intothe mongo shell:

TEST_LOCAL_KEY=$(echo "$(head -c 96 /dev/urandom | base64 | tr -d '\n')")
 
mongo --nodb --shell --eval "var TEST_LOCAL_KEY='$TEST_LOCAL_KEY'"

Create the client-side field level encryption object using thegenerated local key string:

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

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

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

Use the getClientEncryption() method toretrieve the client encryption object:

clientEncryption = encryptedClient.getClientEncryption()

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