JWT
A simple library to work with JSON Web Token and JSON Web Signature (requires PHP 5.5+). The implementation is based on the current draft.
Installation
Package is available on Packagist, you can install it using Composer.
composer require lcobucci/jwt
Dependencies
- PHP 5.5+
- OpenSSL Extension
Basic usage
Creating
Just use the builder to create a new JWT/JWS tokens:
use Lcobucci\JWT\Builder;
$token = (new Builder())->setIssuer('http://example.com') // Configures the issuer (iss claim)
->setAudience('http://example.org') // Configures the audience (aud claim)
->setId('4f1g23a12aa', true) // Configures the id (jti claim), replicating as a header item
->setIssuedAt(time()) // Configures the time that the token was issue (iat claim)
->setNotBefore(time() + 60) // Configures the time that the token can be used (nbf claim)
->setExpiration(time() + 3600) // Configures the expiration time of the token (exp claim)
->set('uid', 1) // Configures a new claim, called "uid"
->getToken(); // Retrieves the generated token
$token->getHeaders(); // Retrieves the token headers
$token->getClaims(); // Retrieves the token claims
echo $token->getHeader('jti'); // will print "4f1g23a12aa"
echo $token->getClaim('iss'); // will print "http://example.com"
echo $token->getClaim('uid'); // will print "1"
echo $token; // The string representation of the object is a JWT string (pretty easy, right?)
Parsing from strings
Use the parser to create a new token from a JWT string (using the previous token as example):
use Lcobucci\JWT\Parser;
$token = (new Parser())->parse((string) $token); // Parses from a string
$token->getHeaders(); // Retrieves the token header
$token->getClaims(); // Retrieves the token claims
echo $token->getHeader('jti'); // will print "4f1g23a12aa"
echo $token->getClaim('iss'); // will print "http://example.com"
echo $token->getClaim('uid'); // will print "1"
Validating
We can easily validate if the token is valid (using the previous token as example):
use Lcobucci\JWT\ValidationData;
$data = new ValidationData(); // It will use the current time to validate (iat, nbf and exp)
$data->setIssuer('http://example.com');
$data->setAudience('http://example.org');
$data->setId('4f1g23a12aa');
var_dump($token->validate($data)); // true, because validation information is equals to data contained on the token
$data->setCurrentTime(time() + 4000); // changing the validation time to future
var_dump($token->validate($data)); // false, because token is expired since current time is greater than exp
Important
- You have to configure
ValidationData
informing all claims you want to validate the token. - If
ValidationData
contains claims that are not being used in token or token has claims that are not configured inValidationData
they will be ignored byToken::validate()
. exp
,nbf
andiat
claims are configured by default inValidationData::__construct()
with the current UNIX time (time()
).
Token signature
We can use signatures to be able to verify if the token was not modified after its generation. This library implements Hmac, RSA and ECDSA signatures (using 256, 384 and 512).
Hmac
Hmac signatures are really simple to be used:
use Lcobucci\JWT\Builder;
use Lcobucci\JWT\Signer\Hmac\Sha256;
$signer = new Sha256();
$token = (new Builder())->setIssuer('http://example.com') // Configures the issuer (iss claim)
->setAudience('http://example.org') // Configures the audience (aud claim)
->setId('4f1g23a12aa', true) // Configures the id (jti claim), replicating as a header item
->setIssuedAt(time()) // Configures the time that the token was issue (iat claim)
->setNotBefore(time() + 60) // Configures the time that the token can be used (nbf claim)
->setExpiration(time() + 3600) // Configures the expiration time of the token (exp claim)
->set('uid', 1) // Configures a new claim, called "uid"
->sign($signer, 'testing') // creates a signature using "testing" as key
->getToken(); // Retrieves the generated token
var_dump($token->verify($signer, 'testing 1')); // false, because the key is different
var_dump($token->verify($signer, 'testing')); // true, because the key is the same
RSA and ECDSA
RSA and ECDSA signatures are based on public and private keys so you have to generate using the private key and verify using the public key:
use Lcobucci\JWT\Builder;
use Lcobucci\JWT\Signer\Keychain; // just to make our life simpler
use Lcobucci\JWT\Signer\Rsa\Sha256; // you can use Lcobucci\JWT\Signer\Ecdsa\Sha256 if you're using ECDSA keys
$signer = new Sha256();
$keychain = new Keychain();
$token = (new Builder())->setIssuer('http://example.com') // Configures the issuer (iss claim)
->setAudience('http://example.org') // Configures the audience (aud claim)
->setId('4f1g23a12aa', true) // Configures the id (jti claim), replicating as a header item
->setIssuedAt(time()) // Configures the time that the token was issue (iat claim)
->setNotBefore(time() + 60) // Configures the time that the token can be used (nbf claim)
->setExpiration(time() + 3600) // Configures the expiration time of the token (exp claim)
->set('uid', 1) // Configures a new claim, called "uid"
->sign($signer, $keychain->getPrivateKey('file://{path to your private key}')) // creates a signature using your private key
->getToken(); // Retrieves the generated token
var_dump($token->verify($signer, $keychain->getPublicKey('file://{path to your public key}'))); // true when the public key was generated by the private one =)
It's important to say that if you're using RSA keys you shouldn't invoke ECDSA signers (and vice-versa), otherwise sign()
and verify()
will raise an exception!