v1.0.1: export and update docs

README.md

@@ -30,11 +30,19 @@ and [Rasha.js (RSA)](https://git.coolaj86.com/coolaj86/rasha.js/).
 A brief (albeit somewhat nonsensical) introduction to the APIs:
 
 ```
-Keypairs.generate().then(function (jwk) {
-  return Keypairs.export({ jwk: jwk }).then(function (pem) {
+Keypairs.generate().then(function (pair) {
+  return Keypairs.export({ jwk: pair.private }).then(function (pem) {
     return Keypairs.import({ pem: pem }).then(function (jwk) {
       return Keypairs.thumbprint({ jwk: jwk }).then(function (thumb) {
         console.log(thumb);
+        return Keypairs.signJwt({
+          jwk: keypair.private
+        , claims: {
+            iss: 'https://example.com'
+          , sub: 'jon.doe@gmail.com'
+          , exp: Math.round(Date.now()/1000) + (3 * 24 * 60 * 60)
+          }
+        });
       });
     });
   });
@@ -44,36 +52,94 @@ Keypairs.generate().then(function (jwk) {
 By default ECDSA keys will be used since they've had native support in node
 _much_ longer than RSA has, and they're smaller, and faster to generate.
 
-## API
+## API Overview
 
-Each of these return a Promise.
+#### Keypairs.generate(options)
 
-* `Keypairs.generate(options)`
-  * options example `{ kty: 'RSA', modulusLength: 2048 }`
-  * options example `{ kty: 'ECDSA', namedCurve: 'P-256' }`
-* `Keypairs.import(options)`
-  * options example `{ pem: '...' }`
-* `Keypairs.export(options)`
-  * options example `{ jwk: jwk }`
-  * options example `{ jwk: jwk, public: true }`
-* `Keypairs.thumbprint({ jwk: jwk })`
+Generates a public/private pair of JWKs as `{ private, public }`
 
-<!--
+Option examples:
 
-* `Keypairs.jws.sign(options)`
-  * options example `{ keypair, header, protected, payload }`
-* `Keypairs.csr.generate(options)`
-  * options example `{ keypair, [ 'example.com' ] }`
+  * RSA `{ kty: 'RSA', modulusLength: 2048 }`
+  * ECDSA `{ kty: 'ECDSA', namedCurve: 'P-256' }`
 
--->
+When no options are supplied EC P-256 (also known as `prime256v1` and `secp256r1`) is used by default.
 
-# Full Documentation
+#### Keypairs.import({ pem: '...' }
 
-Keypairs.js provides a 1-to-1 mapping to the Rasha.js and Eckles.js APIs.
+Takes a PEM in pretty much any format (PKCS1, SEC1, PKCS8, SPKI) and returns a JWK.
 
-The full RSA documentation is at [Rasha.js](https://git.coolaj86.com/coolaj86/rasha.js/)
+#### Keypairs.export(options)
 
-The full ECDSA documentation is at [Eckles.js](https://git.coolaj86.com/coolaj86/eckles.js/)
+Exports a JWK as a PEM.
 
-Any option you pass to Keypairs will be passed directly to the corresponding API
+Exports PEM in PKCS8 (private) or SPKI (public) by default.
+
+Options
+
+```js
+{ jwk: jwk
+, public: true
+, encoding: 'pem' // or 'der'
+, format: 'pkcs8' // or 'ssh', 'pkcs1', 'sec1', 'spki'
+}
+```
+
+#### Keypairs.thumbprint({ jwk: jwk })
+
+Promises a JWK-spec thumbprint: URL Base64-encoded sha256
+
+#### Keypairs.signJwt({ jwk, header, claims })
+
+Returns a JWT (otherwise known as a protected JWS in "compressed" format).
+
+```js
+{ jwk: jwk
+, claims: {
+  }
+}
+```
+
+Header defaults:
+
+```js
+{ kid: thumbprint
+, alg: 'xS256'
+, typ: 'JWT'
+}
+```
+
+Payload notes:
+
+* `iat: now` is added by default (set `false` to disable)
+* `exp` must be set (set `false` to disable)
+* `iss` should be the base URL for JWK lookup (i.e. via OIDC, Auth0)
+
+Notes:
+
+`header` is actually the JWS `protected` value, as all JWTs use protected headers (yay!)
+and `claims` are really the JWS `payload`.
+
+#### Keypairs.signJws({ jwk, header, protected, payload })
+
+This is provided for APIs like ACME (Let's Encrypt) that use uncompressed JWS (instead of JWT, which is compressed).
+
+Options:
+
+* `header` not what you think. Leave undefined unless you need this for the spec you're following.
+* `protected` is the typical JWT-style header
+  * `kid` and `alg` will be added by default (these are almost always required), set `false` explicitly to disable
+* `payload` can be JSON, a string, or even a buffer (which gets URL Base64 encoded)
+  * you must set this to something, even if it's an empty string, object, or Buffer
+
+# Additional Documentation
+
+Keypairs.js provides a 1-to-1 mapping to the Rasha.js and Eckles.js APIs,
+but it also includes the additional convenience methods `signJwt` and `signJws`.
+
+That is to say that any option you pass to Keypairs will be passed directly to the corresponding API
 of either Rasha or Eckles.
+
+* See ECDSA documentation at [Eckles.js](https://git.coolaj86.com/coolaj86/eckles.js/)
+* See RSA documentation at [Rasha.js](https://git.coolaj86.com/coolaj86/rasha.js/)
+

example.js

@@ -0,0 +1,33 @@
+'use strict';
+
+var Keypairs = require('./keypairs.js');
+var Keyfetch = require('keyfetch');
+
+Keypairs.generate().then(function (keypair) {
+  return Keypairs.thumbprint({ jwk: keypair.public }).then(function (thumb) {
+    var iss = 'https://coolaj86.com/';
+
+    // shim so that no http request is necessary
+    keypair.private.kid = thumb;
+    Keyfetch._setCache(iss, { thumbprint: thumb, jwk: keypair.private });
+
+    return Keypairs.signJwt({
+      jwk: keypair.private
+    , claims: {
+        iss: iss
+      , sub: 'coolaj86@gmail.com'
+      , exp: Math.round(Date.now()/1000) + (3 * 24 * 60 * 60)
+      }
+    });
+  });
+}).then(function (jwt) {
+  console.log(jwt);
+  return Keyfetch.verify({ jwt: jwt }).then(function (ok) {
+    if (!ok) {
+      throw new Error("SANITY: did not verify (should have failed)");
+    }
+    console.log("Verified token");
+  });
+}).catch(function (err) {
+  console.error(err);
+});

keypairs.js

@@ -2,7 +2,8 @@
 
 var Eckles = require('eckles');
 var Rasha = require('rasha');
-var Keypairs = {};
+var Enc = {};
+var Keypairs = module.exports;
 
 /*global Promise*/
 
@@ -40,3 +41,120 @@ Keypairs.thumbprint = function (opts) {
     }
   });
 };
+
+// JWT a.k.a. JWS with Claims using Compact Serialization
+Keypairs.signJwt = function (opts) {
+  return Keypairs.thumbprint({ jwk: opts.jwk }).then(function (thumb) {
+    var header = opts.header || {};
+    var claims = JSON.parse(JSON.stringify(opts.claims || {}));
+    header.typ = 'JWT';
+    if (!header.kid) {
+      header.kid = thumb;
+    }
+    if (false === claims.iat) {
+      claims.iat = undefined;
+    } else if (!claims.iat) {
+      claims.iat = Math.round(Date.now()/1000);
+    }
+    if (false === claims.exp) {
+      claims.exp = undefined;
+    } else if (!claims.exp) {
+      throw new Error("opts.claims.exp should be the expiration date (as seconds since the Unix epoch) or false");
+    }
+    if (false === claims.iss) {
+      claims.iss = undefined;
+    } else if (!claims.iss) {
+      throw new Error("opts.claims.iss should be in the form of https://example.com/, a secure OIDC base url");
+    }
+
+    return Keypairs.signJws({
+      jwk: opts.jwk
+    , pem: opts.pem
+    , protected: header
+    , header: undefined
+    , payload: claims
+    }).then(function (jws) {
+      return [ jws.protected, jws.payload, jws.signature ].join('.');
+    });
+  });
+};
+
+Keypairs.signJws = function (opts) {
+  return Keypairs.thumbprint(opts).then(function (thumb) {
+
+    function alg() {
+      if (!opts.jwk) {
+        throw new Error("opts.jwk must exist and must declare 'typ'");
+      }
+      return ('RSA' === opts.jwk.typ) ? "RS256" : "ES256";
+    }
+
+    function sign(pem) {
+      var header = opts.header;
+      var protect = opts.protected;
+      var payload = opts.payload;
+
+      // Compute JWS signature
+      var protectedHeader = "";
+      // Because unprotected headers are allowed, regrettably...
+      // https://stackoverflow.com/a/46288694
+      if (false !== protect) {
+        if (!protect) { protect = {}; }
+        if (!protect.alg) { protect.alg = alg(); }
+        // There's a particular request where Let's Encrypt explicitly doesn't use a kid
+        if (!protect.kid && false !== protect.kid) { protect.kid = thumb; }
+        protectedHeader = JSON.stringify(protect);
+      }
+
+      // Convert payload to Buffer
+      if ('string' !== typeof payload && !Buffer.isBuffer(payload)) {
+        if (!payload) {
+          throw new Error("opts.payload should be JSON, string, or Buffer (it may be empty, but that must be explicit)");
+        }
+        payload = JSON.stringify(payload);
+      }
+      if ('string' === typeof payload) {
+        payload = Buffer.from(payload, 'binary');
+      }
+
+      // node specifies RSA-SHAxxx even whet it's actually ecdsa (it's all encoded x509 shasums anyway)
+      var nodeAlg = "RSA-SHA" + (((protect||header).alg||'').replace(/^[^\d]+/, '')||'256');
+      var protected64 = Enc.strToUrlBase64(protectedHeader);
+      var payload64 = Enc.bufToUrlBase64(payload);
+      var sig = require('crypto')
+        .createSign(nodeAlg)
+        .update(protect ? (protected64 + "." + payload64) : payload64)
+        .sign(pem, 'base64')
+        .replace(/\+/g, '-')
+        .replace(/\//g, '_')
+        .replace(/=/g, '')
+      ;
+
+      return {
+        header: header
+      , protected: protected64 || undefined
+      , payload: payload64
+      , signature: sig
+      };
+    }
+
+    if (opts.pem && opts.jwk) {
+      return sign(opts.pem);
+    } else {
+      return Keypairs.export({ jwk: opts.jwk }).then(sign);
+    }
+  });
+};
+
+Enc.strToUrlBase64 = function (str) {
+  // node automatically can tell the difference
+  // between uc2 (utf-8) strings and binary strings
+  // so we don't have to re-encode the strings
+  return Buffer.from(str).toString('base64')
+    .replace(/\+/g, '-').replace(/\//g, '_').replace(/=/g, '');
+};
+Enc.bufToUrlBase64 = function (buf) {
+  // allow for Uint8Array as a Buffer
+  return Buffer.from(buf).toString('base64')
+    .replace(/\+/g, '-').replace(/\//g, '_').replace(/=/g, '');
+};

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "keypairs",
-  "version": "1.0.0",
+  "version": "1.0.1",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {

package.json

@@ -1,6 +1,6 @@
 {
   "name": "keypairs",
-  "version": "1.0.0",
+  "version": "1.0.1",
   "description": "Lightweight RSA/ECDSA keypair generation and JWK <-> PEM",
   "main": "keypairs.js",
   "files": [],