v1.4.0: add jwk thumbprinting

README.md

@@ -12,6 +12,7 @@ ECDSA (elliptic curve) tools. Lightweight. Zero Dependencies. Universal compatib
 * [x] Fast and Easy EC Key Generation
 * [x] PEM-to-JWK
 * [x] JWK-to-PEM
+* [x] JWK thumbprint
 * [x] SSH "pub" format
 * [x] CLI
   * See [Eckles CLI](https://git.coolaj86.com/coolaj86/eckles-cli.js)
@@ -176,6 +177,14 @@ rMjgyCokrnjDft6Y/YnA4A50yZe7CnFsqeDcpnPbubP6cpYiVcnevNIYyg==
 -----END PUBLIC KEY-----
 ```
 
+## JWK Thumbprint
+
+```js
+Eckles.thumbprint({ jwk: jwk }).then(function (thumbprint) {
+  console.log(thumbprint);
+});
+```
+
 Testing
 -------
 

bin/eckles.js

@@ -39,7 +39,16 @@ try {
   // ignore
 }
 
+var thumbprint = ('thumbprint' === format);
+if (thumbprint) {
+  format = 'public';
+}
+
 if ('string' === typeof key) {
+  if (thumbprint) {
+    Eckles.thumbprint({ pem: key }).then(console.log);
+    return;
+  }
   var pub = (-1 !== [ 'public', 'spki', 'pkix' ].indexOf(format));
   Eckles.import({ pem: key, public: (pub || format) }).then(function (jwk) {
     console.log(JSON.stringify(jwk, null, 2));
@@ -48,6 +57,10 @@ if ('string' === typeof key) {
     process.exit(1);
   });
 } else {
+  if (thumbprint) {
+    Eckles.thumbprint({ jwk: key }).then(console.log);
+    return;
+  }
   Eckles.export({ jwk: key, format: format }).then(function (pem) {
     console.log(pem);
   }).catch(function (err) {

lib/eckles.js

@@ -224,4 +224,27 @@ EC.pack = function (opts) {
   });
 };
 
+EC.__thumbprint = function (jwk) {
+  var buf = require('crypto').createHash('sha256')
+    // alphabetically sorted keys [ 'crv', 'kty', 'x', 'y' ]
+    .update('{"crv":"' + jwk.crv + '","kty":"EC","x":"' + jwk.x + '","y":"' + jwk.y + '"}')
+    .digest()
+  ;
+  return Enc.bufToUrlBase64(buf);
+};
+
+EC.thumbprint = function (opts) {
+  return Promise.resolve().then(function () {
+    var jwk;
+    if ('EC' === opts.kty) {
+      jwk = opts;
+    } else if (opts.jwk) {
+      jwk = opts.jwk;
+    } else {
+      jwk = EC.importSync(opts);
+    }
+    return EC.__thumbprint(jwk);
+  });
+};
+
 EC.toPem = EC.export = EC.pack;

package.json

@@ -1,6 +1,6 @@
 {
   "name": "eckles",
-  "version": "1.3.3",
+  "version": "1.4.0",
   "description": "💯 PEM-to-JWK and JWK-to-PEM (and SSH) for ECDSA keys in a lightweight, zero-dependency library focused on perfect universal compatibility.",
   "homepage": "https://git.coolaj86.com/coolaj86/eckles.js",
   "main": "index.js",

test.sh

@@ -118,6 +118,12 @@ node bin/eckles.js pkcs8 > /dev/null
 node bin/eckles.js ssh #> /dev/null
 echo "PASS"
 
+echo ""
+echo "Testing Thumbprints"
+node bin/eckles.js ./fixtures/privkey-ec-p256.sec1.pem thumbprint
+node bin/eckles.js ./fixtures/pub-ec-p256.jwk.json thumbprint
+echo "PASS"
+
 rm *.2