Introduction

JOSE is a set of high quality specifications that specify how data payloads can be signed/validated and/or encrypted/decrypted with the cryptographic properties set in the JSON-formatted metadata (headers). The data to be secured can be in JSON or some other format (plain text, XML, binary data).

JOSE is a key piece of the advanced OAuth2-based applications such as OpenIdConnect but can also be successfully used for securing the regular HTTP web service communications.

CXF 3.1.x and 3.2.0 provides a complete implementation of JOSE.

Maven Dependencies

Having the following dependency will let the developers write JOSE code: creating and securing JSON Web Tokens (JWT), and securing the arbitrary data (not only JSON)

<dependency>
  <groupId>org.apache.cxf</groupId>
  <artifactId>cxf-rt-rs-security-jose</artifactId>
  <version>3.1.7</version>
</dependency>

Having the following dependency will let the developers use JAX-RS JOSE filters which will transparently sign and/or encrypt the data streams, and decrypt or/and validate the incoming JOSE sequences and make the original data available for the processing.

<dependency>
  <groupId>org.apache.cxf</groupId>
  <artifactId>cxf-rt-rs-security-jose-jaxrs</artifactId>
  <version>3.1.7</version>
</dependency>

JOSE Overview

JOSE consists of the following key parts:

• JWA - JSON Web Algorithms where all supported signature and encryption algorithms are listed
• JWK - JSON Web Keys - introduces a JSON format for describing the public and private keys used by JWA algorithms
• JWS - JSON Web Signature - describes how the data can be signed or validated and introduces compact and JSON JWS formats for representing the signed data
• JWE - JSON Web Encryption - describes how the data can be encrypted or decrypted and introduces compact and JSON JWE formats for representing the encrypted data  

Additionally, JWT (JSON Web Token), while technically not part of JOSE, is often used as an input material to JWS and JWE processors, especially in OAuth2 flows (example: OAuth2 access tokens can be represented internally as JWT, OpenIdConnect IdToken and UserInfo are effectively JWTs). JWT describes how a set of claims in a JSON format can be either JWS-signed or JWE-enctypted. 

JWA Algorithms

All JOSE signature and encryption algorithms are grouped and described in JSON Web Algorithms (JWA) specification.

The algorithms are split into 3 categories: signature algorithms (MAC, RS, ES), algorithms for supporting the encryption of content encryption keys (RSA-OAEP, Aes Key Wrap, etc),

and algorithms for encrypting the actual content (AES GCM, etc).

All encryption algorithms produce authentication tags which provide the protection against manipulating the already encrypted content.

Please refer to this specification to get all the information needed (with the follow up links to the corresponding RFC when applicable) about a particular signature or encryption

algorithm: the properties, recommended key sizes, other security considerations related to all of or some specific algorithms.

CXF offers the utility support for working with JWA algorithms in this package.

JWK Keys

JSON Web Key (JWK) is a JSON document describing the cryptographic key properties. JWKs are very flexible and light-weight (in most cases) and one can expect JWKs becoming one of the major mechanisms for representing and storing cryptographic keys. What is important is that one does not have to use a JWK in order to sign or encrypt the document, working directly with Java JCA secret and asymmetric key representations is sufficient but JWK is a first class citizen in JOSE with all of JOSE examples using JWK representations.

Here is

CXF offers a utility support for reading and writing JWK keys and key sets and for working with the encrypted inlined and standalone JWK stores in this package. Support for the pluggable strategies for loading JWKs is on the map.

JWS Signature

JSON Web Signature (JWS) document describes how a document content can be signed. For example, Appendix A1 shows how the content can be signed with a MAC key.

Here is one of the ways you can do it in CXF, where a Json Web Token (JWT, see one of the next sections) is signed by a MAC key:
 

// sign
JoseHeaders headers = new JoseHeaders();
headers.setAlgorithm(SignatureAlgorithm.HS256.getJwaName());

JwtClaims claims = new JwtClaims();
claims.setIssuer("joe");
claims.setExpiryTime(1300819380L);
claims.setClaim("http://example.com/is_root", Boolean.TRUE);
JwtToken token = new JwtToken(headers, claims);

JwsCompactProducer jws = new JwsJwtCompactProducer(token);

jws.signWith(new HmacJwsSignatureProvider(ENCODED_MAC_KEY, SignatureAlgorithm.HS256));
assertEquals(ENCODED_TOKEN_SIGNED_BY_MAC, jws.getSignedEncodedJws());

// validate
JwsJwtCompactConsumer jws = new JwsJwtCompactConsumer(ENCODED_TOKEN_SIGNED_BY_MAC);
assertTrue(jws.verifySignatureWith(new HmacJwsSignatureVerifier(ENCODED_MAC_KEY,
                                      SignatureAlgorithm.HS256)));
JwtToken token = jws.getJwtToken();
JoseHeaders headers = token.getHeaders();
assertEquals(SignatureAlgorithm.HS256.getJwaName(), headers.getAlgorithm());
validateClaims(token.getClaims());

CXF ships JWS related classes in this package and offers a support for all of JWA signature algorithms.

JwsSignatureProvider supports signing the content, JwsSignatureVerifier - validating the signatures. Providers and verifiers supporting RSA, HMac and Elliptic Curve signature algorithms are shipped.

JwsCompactConsumer and JwsCompactProducer offer a utility support for creating and validating JWS compact serialization and accept keys in a variety of formats

(as JWKs, JCA representations, created out of band and wrapped in either JwsSignatureProvider or JwsSignatureVerifier).

JwsJwtCompactConsumer and JwsJwtCompactProducer are JwsCompactConsumer and JwsCompactProducer specializations that offer a utility support for signing Json Web Tokens in a compact format.

JwsJsonConsumer and JwsJsonProducer support JWS JSON (full) serialization.

JwsOutputStream and JwsJsonOutputStream are specialized output streams that can be used in conjunction with JWS JAX-RS filters (see one of the next sections)

to support the best effort at streaming the content while signing it.  These classes will use JwsSignature  optionally returned from JwsSignatureProvider

instead of working with the consumer utility classes which deal with the signature process completely in memory.

Many more examples will be added here.

JWE Encryption

JSON Web Signature (JWE) document describes how a document content, and, when applicable, a content encryption key, can be encrypted. For example, Appendix A1 shows how the content can be encrypted

with a secret key using Aes Gcm with the actual content encryption key encrypted/wrapped using RSA-OAEP.

Here is the example for doing Aes Cbc HMac and Aes Key Wrap in CXF:

final String specPlainText = "Live long and prosper.";
        
byte[] cekEncryptionKey = Base64UrlUtility.decode(KEY_ENCRYPTION_KEY_A3);
        
AesWrapKeyEncryptionAlgorithm keyEncryption = new AesWrapKeyEncryptionAlgorithm(cekEncryptionKey, KeyAlgorithm.A128KW);
JweEncryptionProvider encryption = new AesCbcHmacJweEncryption(ContentAlgorithm.A128CBC_HS256,
                                                               CONTENT_ENCRYPTION_KEY_A3, 
                                                               INIT_VECTOR_A3,
                                                               keyEncryption);
String jweContent = encryption.encrypt(specPlainText.getBytes("UTF-8"), null);
assertEquals(JWE_OUTPUT_A3, jweContent);
        
AesWrapKeyDecryptionAlgorithm keyDecryption = new AesWrapKeyDecryptionAlgorithm(cekEncryptionKey);
JweDecryptionProvider decryption = new AesCbcHmacJweDecryption(keyDecryption);
String decryptedText = decryption.decrypt(jweContent).getContentText();
assertEquals(specPlainText, decryptedText);

CXF ships JWE related classes in this package and offers a support for all of JWA encryption algorithms.

JweEncryptionProvider supports encrypting the content, JweDecryptionProvider - decrypting the content. Encryptors and Decryptors for all of JWE algorithms are shipped.

JweCompactConsumer and JweCompactProducer offer a utility support for creating and validating JWE compact serialization and accept keys in a variety of formats

(as JWKs, JCA representations, created out of band and wrapped in either JweEncryptionProvider or JweDecryptionProvider).

JweJwtCompactConsumer and JweJwtCompactProducer are JweCompactConsumer and JweCompactProducer specializations that offer a utility support for encrypting Json Web Tokens in a compact format.

JweJsonConsumer and JweJsonProducer support JWE JSON (full) serialization.

JweOutputStream is a specialized output stream that can be used in conjunction with JWE JAX-RS filters (see one of the next sections)

to support the best effort at streaming the content while encrypting it.  These classes will use JweEncryptionOutput  optionally returned from JweEncryptionProvider

instead of working with the consumer utility classes which deal with the encryption process completely in memory.

Many more examples will be added here.

JSON Web Tokens

JSON Web Token (JWT) is a collection of claims in JSON format. It offers a standard JSON container for representing various properties or claims.

JWT can be signed and or encrypted, i.e, serve as a JOSE signature or encryption input like any other data structure.

JWT has been primarily used in OAuth2 applications to represent self-contained access tokens but can also be used in other contexts.

CXF offers an initial JWT support in this package.

Linking JWT authentications to JWS or JWE content

Add more...

JOSE JAX-RS Filters

JWE

JWS

Configuration

Configuration that applies to both encryption and signature

Configuration that applies to signature only

Configuration that applies to encryption only

Configuration that applies to JWT tokens only

Encrypting JWK stores

JAX-RS filters can read the keys from encrypted JWK stores. The stores are encrypted inline or in separate storages (files). By default the filters expect that the stores has been encrypted using

a password based PBES2 algorithm. The filters will check a registered password provider.

OAuth2 and Jose

CXF OAuth2 module depends on its JOSE module. This will be used to support OAuth2 POP tokens. Authorization code JOSE requests can already be processed. Utility support for validating JWT-based access tokens is provided.

Add more...

OIDC and Jose

OIDC heavily depends on JOSE. CXF OIDC module utilizes a JOSE module to support OIDC RP and IDP code. Add more...

Future Work

OAuth2, WebCrypto, OIDC, etc

Third-Party Alternatives

Jose4J is a top project from Brian Campbell.  CXF users are encouraged to experiment with Jose4J (or indeed with other 3rd party implementations) if they prefer.

TODO: describe how Jose4J can be integrated with CXF filters if preferred.