org.apache.iceberg.encryption

Interface KmsClient

All Superinterfaces:

java.io.Serializable

public interface KmsClient
extends java.io.Serializable

A minimum client interface to connect to a key management service (KMS).

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	KmsClient.KeyGenerationResult For KMS systems that support key generation, this class keeps the key generation result - the raw secret key, and its wrap.

Method Summary

Modifier and Type	Method and Description
default KmsClient.KeyGenerationResult	generateKey(java.lang.String wrappingKeyId) Generate a new secret key in the KMS server, and wrap it using a wrapping/master key which is stored in KMS and referenced by an ID.
void	initialize(java.util.Map<java.lang.String,java.lang.String> properties) Initialize the KMS client with given properties
default boolean	supportsKeyGeneration() Some KMS systems support generation of secret keys inside the KMS server.
java.nio.ByteBuffer	unwrapKey(java.lang.String wrappedKey, java.lang.String wrappingKeyId) Unwrap a secret key, using a wrapping/master key which is stored in KMS and referenced by an ID.
java.lang.String	wrapKey(java.nio.ByteBuffer key, java.lang.String wrappingKeyId) Wrap a secret key, using a wrapping/master key which is stored in KMS and referenced by an ID.

Method Detail

wrapKey

java.lang.String wrapKey(java.nio.ByteBuffer key,
                         java.lang.String wrappingKeyId)

Wrap a secret key, using a wrapping/master key which is stored in KMS and referenced by an ID. Wrapping means encryption of the secret key with the master key, and adding optional KMS-specific metadata that allows the KMS to decrypt the secret key in an unwrapping call.

Parameters:

key - a secret key being wrapped

wrappingKeyId - a key ID that represents a wrapping key stored in KMS

Returns:

wrapped key material

supportsKeyGeneration

default boolean supportsKeyGeneration()

Some KMS systems support generation of secret keys inside the KMS server.

Returns:

true if KMS server supports key generation and KmsClient implementation is interested to leverage this capability. Otherwise, return false - Iceberg will then generate secret keys locally (using the SecureRandom mechanism) and call wrapKey(ByteBuffer, String) to wrap them in KMS.

generateKey

default KmsClient.KeyGenerationResult generateKey(java.lang.String wrappingKeyId)

Generate a new secret key in the KMS server, and wrap it using a wrapping/master key which is stored in KMS and referenced by an ID. This method will be called only if supportsKeyGeneration returns true.

Parameters:

wrappingKeyId - a key ID that represents a wrapping key stored in KMS

Returns:

key in two forms: raw, and wrapped with the given wrappingKeyId

unwrapKey

java.nio.ByteBuffer unwrapKey(java.lang.String wrappedKey,
                              java.lang.String wrappingKeyId)

Unwrap a secret key, using a wrapping/master key which is stored in KMS and referenced by an ID.

Parameters:

wrappedKey - wrapped key material (encrypted key and optional KMS metadata, returned by the wrapKey method)

wrappingKeyId - a key ID that represents a wrapping key stored in KMS

Returns:

raw key bytes

initialize

void initialize(java.util.Map<java.lang.String,java.lang.String> properties)

Initialize the KMS client with given properties

Parameters:

properties - kms client properties