org.bouncycastle.cms.bc

Class BcCMSContentEncryptorBuilder

java.lang.Object

org.bouncycastle.cms.bc.BcCMSContentEncryptorBuilder

public class BcCMSContentEncryptorBuilder
extends java.lang.Object

Lightweight builder for the content encryptor used in CMS EnvelopedData, AuthEnvelopedData and EncryptedData structures — i.e. it encrypts the actual transmitted (or stored) content.

The no-arg build() call generates a fresh content-encryption key internally, which is the right behaviour for EnvelopedData where the CEK is freshly drawn per message and wrapped per recipient. Callers that already have a key — e.g. building an EncryptedData blob over a long-lived locally-stored key (no recipients, no intermediate key wrap) — should use build(byte[]) or build(KeyParameter) instead.

Constructor Summary

Constructors

Constructor and Description
BcCMSContentEncryptorBuilder(org.bouncycastle.asn1.ASN1ObjectIdentifier encryptionOID)
BcCMSContentEncryptorBuilder(org.bouncycastle.asn1.ASN1ObjectIdentifier encryptionOID, int keySize)

Method Summary

Modifier and Type	Method and Description
OutputEncryptor	build() Build the OutputEncryptor with an internally generated key.
OutputEncryptor	build(byte[] rawEncKey) Build the OutputEncryptor using a pre-generated key.
OutputEncryptor	build(org.bouncycastle.crypto.params.KeyParameter encKey) Build the OutputEncryptor using a pre-generated key in lightweight KeyParameter form.
BcCMSContentEncryptorBuilder	setSecureRandom(java.security.SecureRandom random)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

BcCMSContentEncryptorBuilder

public BcCMSContentEncryptorBuilder(org.bouncycastle.asn1.ASN1ObjectIdentifier encryptionOID)

BcCMSContentEncryptorBuilder

public BcCMSContentEncryptorBuilder(org.bouncycastle.asn1.ASN1ObjectIdentifier encryptionOID,
                                    int keySize)

Method Detail

setSecureRandom

public BcCMSContentEncryptorBuilder setSecureRandom(java.security.SecureRandom random)

build

public OutputEncryptor build()
                      throws CMSException

Build the OutputEncryptor with an internally generated key.

Returns:

an OutputEncryptor configured to use an internal key.

Throws:

CMSException

build

public OutputEncryptor build(byte[] rawEncKey)
                      throws CMSException

Build the OutputEncryptor using a pre-generated key.

Parameters:

rawEncKey - a raw byte encoding of the key to be used for encryption.

Returns:

an OutputEncryptor configured to use rawEncKey.

Throws:

CMSException

build

public OutputEncryptor build(org.bouncycastle.crypto.params.KeyParameter encKey)
                      throws CMSException

Build the OutputEncryptor using a pre-generated key in lightweight KeyParameter form. The lightweight peer of JceCMSContentEncryptorBuilder.build(SecretKey); useful when the caller already holds a KeyParameter (e.g. derived via HKDFBytesGenerator or returned by another BC lightweight key agreement) and would otherwise round-trip the key through byte[] for no reason.

Parameters:

encKey - the pre-generated key to use for content encryption.

Returns:

an OutputEncryptor configured to use encKey.

Throws:

CMSException