Nested Tokens

JWT can be signed or encrypted and both. A nested token is a signed token enclosed in an encrypted one. This order is very important: signed then encrypted.
The NestedTokenLoader and NestedTokenBuilder classes will help you to create nested tokens with ease. Just instal the package web-token/jwt-nested-token. It contains all the classes and dependencies will be directly managed by composer. You can install it if needed.
Nested Token Loading
To instantiate the NestedTokenLoader, you need a JWSLoader and a JWELoader.
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use Jose\Component\NestedToken\NestedTokenLoader;
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​
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$nestedTokenLoader = new NestedTokenLoader($jweLoader, $jwsLoader);
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Its use is very straightforward, you just have to call the method load using the token, the encryption and signature key sets.
The last argument ($signature in the following example) will represents the signature index of the verified signature. This is only useful when multiple signature support is used.
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$jws = $nestedTokenLoader->load($token, $encryptionKeySet, $signatureKeySet, $signature);
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Nested Token Building
To instantiate the NestedTokenBuilder, you will need the following components:
a JWSBuilder,
a JWEBuilder, 
a JWESerializerManager,
a JWSSerializerManager
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use Jose\Component\NestedToken\NestedTokenBuilder;
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​
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$nestedTokenBuilder = new NestedTokenBuilder($jweLoader, $jweSerializerManager, $jwsLoader, $jwsSerializerManager);
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Its use is a bit more complicated than the loading as the nested token may be designed for several recipients or may have several signatures.
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$token = $builder->create(
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    $payload,                                     // The payload to protect
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    [[                                            // A list of signatures. 'key' is mandatory and at least one of 'protected_header'/'header' has to be set.
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        'key'              => $signature_key,     // The key used to sign. Mandatory.
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        'protected_header' => ['alg' => 'PS256'], // The protected header. Optional.
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        'header'           => ['foo' => 'bar'],   // The unprotected header. Optional.
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    ]],
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    'jws_json_flattened',                         // The serialization mode for the JWS
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    ['alg' => 'RSA-OAEP', 'enc' => 'A128GCM'],    // The shared protected header. Optional.
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    ['foo' => 'bar'],                             // The shared unprotected header. Optional.
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    [[                                            // A list of recipients. 'key' is mandatory.
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        'key'    => $encryption_key,              // The recipient key.
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        'header' => ['bar' => 'foo'],             // The recipient unprotected header.
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    ]],
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    'jwe_json_flattened'                          // The serialization mode for the JWE.
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    '1, 2, 3, 4'                                  // Additional Authenticated Data (AAD). Optional.
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);
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As a reminder, if one of the following parameter is set, the compact serialization mode cannot be used:
signature unprotected header,
JWE shared unprotected header,
recipient unprotected header,
Additional Authenticated Data.
Symfony Bundle
Configuration
Hereafter an example of a Symfony application configuration:
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jose:
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    nested_token:
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        loaders:
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            loader_1:
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                signature_algorithms: ['PS256']
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                key_encryption_algorithms: ['RSA-OAEP']
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                content_encryption_algorithms: ['A128GCM']
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                jws_serializers: ['jws_compact']
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                jws_header_checkers: [...]
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                jwe_serializers: ['jwe_compact']
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                jwe_header_checkers: [...]
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                is_public: true
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        builders:
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            builder_1:
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                signature_algorithms: ['PS256']
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                key_encryption_algorithms: ['RSA-OAEP']
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                content_encryption_algorithms: ['A128GCM']
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                jws_serializers: ['jws_compact']
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                jwe_serializers: ['jwe_compact']
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                is_public: true
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This configuration will create two public services:
jose.nested_token_loader.loader_1
jose.nested_token_builder.builder_1
These services can be called from the container (unless private) or injected in your services.
Configuration Helper
As any other services, you can create a nested token loader or builder from another bundle extension. The following bundle extension class will create the same configuration and services as above.
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class AcmeExtension extends Extension implements PrependExtensionInterface
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{
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    ...
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​
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    public function prepend(ContainerBuilder $container)
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    {
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        ConfigurationHelper::addNestedTokenLoader($container, 'loader_1', ['jwe_compact'], ['RSA-OAEP'], ['A128GCM'], ['DEF'], [], ['jws_compact'], ['PS256'], [], true, []);
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        ConfigurationHelper::addNestedTokenBuilder($container, 'builder_1', ['jwe_compact'], ['RSA-OAEP'], ['A128GCM'], ['DEF'], ['jws_compact'], ['PS256'], true, []);
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    }
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}
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Contents

Nested Token Loading

Nested Token Building

Symfony Bundle

Configuration

Configuration Helper