117 lines
		
	
	
		
			3.7 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			117 lines
		
	
	
		
			3.7 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| 'use strict';
 | |
| 
 | |
| var crypto = require('crypto');
 | |
| var PromiseA = require('bluebird');
 | |
| var OpErr = PromiseA.OperationalError;
 | |
| var makeB64UrlSafe = require('./common').makeB64UrlSafe;
 | |
| 
 | |
| function thumbprint(jwk) {
 | |
|   // To produce a thumbprint we need to create a JSON string with only the required keys for
 | |
|   // the key type, with the keys sorted lexicographically and no white space. We then need
 | |
|   // run it through a SHA-256 and encode the result in url safe base64.
 | |
|   // https://stackoverflow.com/questions/42588786/how-to-fingerprint-a-jwk
 | |
|   var keys;
 | |
|   if (jwk.kty === 'EC') {
 | |
|     keys = ['crv', 'x', 'y'];
 | |
|   } else if (jwk.kty === 'RSA') {
 | |
|     keys = ['e', 'n'];
 | |
|   } else {
 | |
|     return PromiseA.reject(new Error('invalid JWK key type ' + jwk.kty));
 | |
|   }
 | |
|   keys.push('kty');
 | |
|   keys.sort();
 | |
| 
 | |
|   var missing = keys.filter(function (name) { return !jwk.hasOwnProperty(name); });
 | |
|   if (missing.length > 0) {
 | |
|     return PromiseA.reject(new Error('JWK of type '+jwk.kty+' missing fields ' + missing));
 | |
|   }
 | |
| 
 | |
|   // I'm not 100% sure this behavior is guaranteed by a real standard, but when we use an array
 | |
|   // as the replacer argument the keys are always in the order they appeared in the array.
 | |
|   var jwkStr = JSON.stringify(jwk, keys);
 | |
|   var hash = crypto.createHash('sha256').update(jwkStr).digest('base64');
 | |
|   return PromiseA.resolve(makeB64UrlSafe(hash));
 | |
| }
 | |
| 
 | |
| function sanitizeJwk(jwk) {
 | |
|   // We need to sanitize the key to make sure we don't deliver any private keys fields if
 | |
|   // we were given a key we could use to sign tokens on behalf of the user. We also don't
 | |
|   // want to deliver the sub or any other PPIDs.
 | |
|   var whitelist = ['kty', 'alg', 'kid', 'use'];
 | |
|   if (jwk.kty === 'EC') {
 | |
|     whitelist = whitelist.concat(['crv', 'x', 'y']);
 | |
|   } else if (jwk.kty === 'RSA') {
 | |
|     whitelist = whitelist.concat(['e', 'n']);
 | |
|   }
 | |
| 
 | |
|   var result = {};
 | |
|   whitelist.forEach(function (key) {
 | |
|     result[key] = jwk[key];
 | |
|   });
 | |
|   return result;
 | |
| }
 | |
| 
 | |
| function create(app) {
 | |
|   var restful = {};
 | |
| 
 | |
|   async function getRawKey(req) {
 | |
|     var store = await req.getSiteStore();
 | |
| 
 | |
|     if (req.params.kid === req.experienceId) {
 | |
|       return store.IssuerOauth3OrgPrivateKeys.get(req.experienceId);
 | |
|     }
 | |
| 
 | |
|     // The keys are stored by the issuer PPID, but the sub we have might be a different PPID
 | |
|     // for a 3rd party.
 | |
|     var issuerSub;
 | |
|     try {
 | |
|       issuerSub = await require('./common').getPrimarySub(store.IssuerOauth3OrgGrants, req.params.sub);
 | |
|     } catch (err) {
 | |
|       if (/collision/.test(err.message)) {
 | |
|         err.message = 'PPID collision - unable to safely retrieve keys';
 | |
|       }
 | |
|       throw err;
 | |
|     }
 | |
| 
 | |
|     if (!issuerSub) {
 | |
|       throw new OpErr("unknown PPID '" + req.params.sub + "'");
 | |
|     }
 | |
|     return store.IssuerOauth3OrgJwks.get(issuerSub + '/' + req.params.kid);
 | |
|   }
 | |
| 
 | |
|   restful.get = function (req, res) {
 | |
|     var promise = PromiseA.resolve(getRawKey(req)).then(function (jwk) {
 | |
|       if (!jwk) {
 | |
|         throw new OpErr("no keys stored with kid '"+req.params.kid+"' for PPID "+req.params.sub);
 | |
|       }
 | |
|       return sanitizeJwk(jwk);
 | |
|     });
 | |
| 
 | |
|     app.handlePromise(req, res, promise, "[issuer@oauth3.org] retrieve JWK");
 | |
|   };
 | |
|   restful.saveNew = function (req, res) {
 | |
|     var jwk = req.body;
 | |
|     var promise = thumbprint(jwk).then(function (kid) {
 | |
|       if (jwk.kid && jwk.kid !== kid) {
 | |
|         throw new OpErr('provided kid "'+jwk.kid+'" does not match calculated "'+kid+'"');
 | |
|       }
 | |
|       jwk.kid = kid;
 | |
|       jwk.sub = req.params.sub;
 | |
| 
 | |
|       return req.Store.upsert(jwk.sub+'/'+jwk.kid, jwk);
 | |
|     }).then(function () {
 | |
|       return { success: true };
 | |
|     });
 | |
| 
 | |
|     app.handlePromise(req, res, promise, "[issuer@oauth3.org] save JWK");
 | |
|   };
 | |
| 
 | |
|   return {
 | |
|     thumbprint: thumbprint,
 | |
|     restful: restful,
 | |
|   };
 | |
| }
 | |
| 
 | |
| module.exports.thumbprint = thumbprint;
 | |
| module.exports.create = create;
 |