node-jose
A JavaScript implementation of the JSON Object Signing and Encryption (JOSE) for current web browsers and node.js-based servers. This library implements (wherever possible) all algorithms, formats, and options in JWS, JWE, JWK, and JWA and uses native cryptographic support (WebCrypto API or node.js' "crypto" module) where feasible.
Installing
To install the latest from NPM:
npm install node-jose
Or to install a specific release:
npm install node-jose@0.3.0
Alternatively, the latest unpublished code can be installed directly from the repository:
npm install git+ssh://git@github.com:cisco/node-jose.git
Basics
Require the library as normal:
var jose = require('node-jose');
This library uses Promises for nearly every operation.
This library supports Browserify. To use in a web browser, require('node-jose') and bundle with the rest of your app.
The content to be signed/encrypted or returned from being verified/decrypted are Buffer objects.
Keys and Key Stores
The jose.JWK namespace deals with JWK and JWK-sets.
jose.JWK.Keyis a logical representation of a JWK, and is the "raw" entry point for various cryptographic operations (e.g., sign, verify, encrypt, decrypt).jose.JWK.KeyStorerepresents a collection of Keys.
Creating a JWE or JWS ultimately require one or more explicit Key objects.
Processing a JWE or JWS relies on a KeyStore.
Obtaining a KeyStore
To create an empty keystore:
keystore = jose.JWK.createKeyStore();
To import a JWK-set as a keystore:
// {input} is a String or JSON object representing the JWK-set
jose.JWK.asKeyStore(input).
then(function(result) {
// {result} is a jose.JWK.KeyStore
keystore = result;
});
Exporting a KeyStore
To export the public keys of a keystore as a JWK-set:
output = keystore.toJSON();
To export all the keys of a keystore:
output = keystore.toJSON(true);
Retrieving Keys
To retrieve a key from a keystore:
// by 'kid'
key = keystore.get(kid);
This retrieves the first key that matches the given {kid}. If multiple keys have the same {kid}, you can further narrow what to retrieve:
// ... and by 'kty'
key = keystore.get(kid, { kty: 'RSA' });
// ... and by 'use'
key = keystore.get(kid, { use: 'enc' });
// ... and by 'alg'
key = keystore.get(kid, { use: 'RSA-OAEP' });
// ... and by 'kty' and 'use'
key = keystore.get(kid, { kty: 'RSA', use: 'enc' });
// same as above, but with a single {props} argument
key = keystore.get({ kid: kid, kty: 'RSA', use: 'enc' });
Searching for Keys
To retrieve all the keys from a keystore:
everything = keystore.all();
all() can be filtered much like get():
// filter by 'kid'
everything = keystore.all({ kid: kid });
// filter by 'kty'
everything = keystore.all({ kty: 'RSA' });
// filter by 'use'
everything = keystore.all({ use: 'enc' });
// filter by 'alg'
everything = keystore.all({ alg: 'RSA-OAEP' });
// filter by 'kid' + 'kty' + 'alg'
everything = keystore.all({ kid: kid, kty: 'RSA', alg: 'RSA-OAEP' });
Managing Keys
To import an existing Key (as a JSON object or Key instance):
// input is either a:
// * jose.JWK.Key to copy from; or
// * JSON object representing a JWK; or
keystore.add(input).
then(function(result) {
// {result} is a jose.JWK.Key
key = result;
});
To import and existing Key from a PEM or DER:
// input is either a:
// * String serialization of a JSON JWK/(base64-encoded) PEM/(binary-encoded) DER
// * Buffer of a JSON JWK/(base64-encoded) PEM/(binary-encoded) DER
// form is either a:
// * "json" for a JSON stringified JWK
// * "private" for a DER encoded 'raw' private key
// * "pkcs8" for a DER encoded (unencrypted!) PKCS8 private key
// * "public" for a DER encoded SPKI public key (alternate to 'spki')
// * "spki" for a DER encoded SPKI public key
// * "pkix" for a DER encoded PKIX X.509 certificate
// * "x509" for a DER encoded PKIX X.509 certificate
// * "pem" for a PEM encoded of PKCS8 / SPKI / PKIX
keystore.add(input, form).
then(function(result) {
// {result} is a jose.JWK.Key
});
To generate a new Key:
// first argument is the key type (kty)
// second is the key size (in bits) or named curve ('crv') for "EC"
keystore.generate("oct", 256).
then(function(result) {
// {result} is a jose.JWK.Key
key = result;
});
// ... with properties
var props = {
kid: 'gBdaS-G8RLax2qgObTD94w',
alg: 'A256GCM',
use: 'enc'
};
keystore.generate("oct", 256, props).
then(function(result) {
// {result} is a jose.JWK.Key
key = result;
});
To remove a Key from its Keystore:
kestyore.remove(key);
// NOTE: key.keystore does not change!!
Importing and Exporting a Single Key
To import a single Key:
// where input is either a:
// * jose.JWK.Key instance
// * JSON Object representation of a JWK
jose.JWK.asKey(input).
then(function(result) {
// {result} is a jose.JWK.Key
// {result.keystore} is a unique jose.JWK.KeyStore
});
// where input is either a:
// * String serialization of a JSON JWK/(base64-encoded) PEM/(binary-encoded) DER
// * Buffer of a JSON JWK/(base64-encoded) PEM/(binary-encoded) DER
// form is either a:
// * "json" for a JSON stringified JWK
// * "pkcs8" for a DER encoded (unencrypted!) PKCS8 private key
// * "spki" for a DER encoded SPKI public key
// * "pkix" for a DER encoded PKIX X.509 certificate
// * "x509" for a DER encoded PKIX X.509 certificate
// * "pem" for a PEM encoded of PKCS8 / SPKI / PKIX
jose.JWK.asKey(input, form).
then(function(result) {
// {result} is a jose.JWK.Key
// {result.keystore} is a unique jose.JWK.KeyStore
});
To export the public portion of a Key as a JWK:
var output = key.toJSON();
To export the public and private portions of a Key:
var output = key.toJSON(true);
Obtaining a Key's Thumbprint
To get or calculate a RFC 7638 thumbprint for a key:
// where hash is a supported algorithm, currently one of:
// * SHA-1
// * SHA-256
// * SHA-384
// * SHA-512
key.thumbprint(hash).
then(function(print) {
// {print} is a Buffer containing the thumbprint binary value
});
When importing or generating a key that does not have a "kid" defined, a "SHA-256" thumbprint is calculated and used as the "kid".
Signatures
Signing Content
At its simplest, to create a JWS:
// {input} is a Buffer
jose.JWS.createSign(key).
update(input).
final().
then(function(result) {
// {result} is a JSON object -- JWS using the JSON General Serialization
});
The JWS is signed using the preferred algorithm appropriate for the given Key. The preferred algorithm is the first item returned by key.algorithms("sign").
To create a JWS using another serialization format:
jose.JWS.createSign({ format: 'flattened' }, key).
update(input).
final().
then(function(result) {
// {result} is a JSON object -- JWS using the JSON Flattened Serialization
});
jose.JWS.createSign({ format: 'compact' }, key).
update(input).
final().
then(function(result) {
// {result} is a String -- JWS using the Compact Serialization
});
To create a JWS using a specific algorithm:
jose.JWS.createSign({ alg: 'PS256' }, key).
update(input).
final().
then(function(result) {
// ....
});
To create a JWS for a specified content type:
jose.JWS.createSign({ fields: { cty: 'jwk+json' } }, key).
update(input).
final().
then(function(result) {
// ....
});
To create a JWS from String content:
jose.JWS.createSign(key).
update(input, "utf8").
final().
then(function(result) {
// ....
});
To create a JWS with multiple signatures:
// {keys} is an Array of jose.JWK.Key instances
jose.JWS.createSign(keys).
update(input).
final().
then(function(result) {
// ....
});
Verifying a JWS
To verify a JWS, and retrieve the payload:
jose.JWS.createVerify(keystore).
verify(input).
then(function(result) {
// {result} is a Object with:
// * header: the combined 'protected' and 'unprotected' header members
// * payload: Buffer of the signed content
// * signature: Buffer of the verified signature
// * key: The key used to verify the signature
});
To verify using an implied Key:
// {key} can be:
// * jose.JWK.Key
// * JSON object representing a JWK
jose.JWS.createVerify(key).
verify(input).
then(function(result) {
// ...
});
Encryption
Encrypting Content
At its simplest, to create a JWE:
// {input} is a Buffer
jose.JWE.createEncrypt(key).
update(input).
final().
then(function(result) {
// {result} is a JSON Object -- JWE using the JSON General Serialization
});
How the JWE content is encrypted depends on the provided Key.
- If the Key only supports content encryption algorithms, then the preferred algorithm is used to encrypt the content and the key encryption algorithm (i.e., the "alg" member) is set to "dir". The preferred algorithm is the first item returned by
key.algorithms("encrypt"). - If the Key supports key management algorithms, then the JWE content is encrypted using "A128CBC-HS256" by default, and the Content Encryption Key is encrypted using the preferred algorithms for the given Key. The preferred algorithm is the first item returned by
key.algorithms("wrap").
To create a JWE using a different serialization format:
jose.JWE.createEncrypt({ format: 'compact' }, key).
update(input).
final().
then(function(result) {
// {result} is a String -- JWE using the Compact Serialization
});
jose.JWE.createEncrypt({ format: 'flattened' }, key).
update(input).
final().
then(function(result) {
// {result} is a JSON Object -- JWE using the JSON Flattened Serialization
});
To create a JWE and compressing the content before encrypting:
jose.JWE.createEncrypt({ zip: true }, key).
update(input).
final().
then(function(result) {
// ....
});
To create a JWE for a specific content type:
jose.JWE.createEncrypt({ fields: { cty : 'jwk+json' } }, key).
update(input).
final().
then(function(result) {
// ....
});
To create a JWE with multiple recipients:
// {keys} is an Array of jose.JWK.Key instances
jose.JWE.createEncrypt(keys).
update(input).
final().
then(function(result) {
// ....
});
Decrypting a JWE
To decrypt a JWE, and retrieve the plaintext:
jose.JWE.createDecrypt(keystore).
decrypt(input).
then(function(result) {
// {result} is a Object with:
// * header: the combined 'protected' and 'unprotected' header members
// * key: Key used to decrypt
// * payload: Buffer of the decrypted content
// * plaintext: Buffer of the decrypted content (alternate)
});
To decrypt a JWE using an implied key:
jose.JWE.createDecrypt(key).
decrypt(input).
then(function(result) {
// ....
});
Useful Utilities
Converting to Buffer
To convert a Typed Array, ArrayBuffer, or Array of Numbers to a Buffer:
buff = jose.util.asBuffer(input);
URI-Safe Base64
This exposes urlsafe-base64's encode and decode methods as encode and decode (respectively).
To convert from a Buffer to a base64uri-encoded String:
var output = jose.util.base64url.encode(input);
To convert a String to a base64uri-encoded String:
// explicit encoding
output = jose.util.base64url.encode(input, "utf8");
// implied "utf8" encoding
output = jose.util.base64url.encode(input);
To convert a base64uri-encoded String to a Buffer:
var output = jose.util.base64url.decode(input);
Random Bytes
To generate a Buffer of octets, regardless of platform:
// argument is size (in bytes)
var rnd = jose.util.randomBytes(32);
This function uses:
crypto.randomBytes()on node.jscrypto.getRandomValues()on modern browsers- A PRNG based on AES and SHA-1 for older platforms