v1.0.0: parse SSH public keys in the browser

5 years ago · 86ee62e0d3
5 changed files with 327 additions and 0 deletions
--- a/README.md
+++ b/README.md
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+# Bluecrypt&trade SSH to JWK (for Browsers)
+
+A minimal library to parse an SSH public key (`id_rsa.pub`)
+and convert it into a public JWK using Vanilla JS.
+
+Works for RSA and ECDSA public keys.
+
+# Features
+
+&lt; 150 lines of code | 1.0kb gzipped | 2.4kb minified | 3.7kb with comments
+
+* [x] SSH Public Keys
+* [x] RSA Public Keys
+* [x] EC Public Keys
+  * P-256 (prime256v1, secp256r1)
+  * P-384 (secp384r1)
+* [x] node.js version
+  * [ssh-to-jwk.js](https://git.coolaj86.com/coolaj86/ssh-to-jwk.js)
+
+### Need SSH Private Keys?
+
+SSH private keys (`id_rsa`) are just normal PEM files,
+so you can use Eckles or Rasha, as mentioned above.
+
+# Web Demo
+
+<https://coolaj86.com/demos/ssh-to-jwk/>
+
+```bash
+git clone https://git.coolaj86.com/coolaj86/bluecrypt-ssh-to-jwk.js
+pushd bluecrypt-ssh-to-jwk.js/
+```
+
+```bash
+open index.html
+```
+
+# Usage
+
+You can also use it as a library:
+
+```html
+<script src="https://git.coolaj86.com/coolaj86/bluecrypt-ssh-to-jwk.js/raw/branch/master/ssh-to-jwk.js"></script>
+```
+
+```js
+var pub = 'ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBCE9Uli8bGnD4hOWdeo5KKQJ/P/vOazI4MgqJK54w37emP2JwOAOdMmXuwpxbKng3KZz27mz+nKWIlXJ3rzSGMo= root@localhost';
+
+var ssh = SSH.parse(pub);
+
+console.info(ssh.jwk);
+```
+
+# Other Tools in the Bluecrypt Suite
+
+* [Bluecrypt JWK to SSH](https://git.coolaj86.com/coolaj86/jwk-to-ssh.js) (RSA, EC, SSH)
+* [Bluecrypt ASN.1 decoder](https://git.coolaj86.com/coolaj86/asn1-parser.js) (x509, RSA, EC, etc)
+* [Bluecrypt ASN.1 builder](https://git.coolaj86.com/coolaj86/asn1-packer.js) (x509, RSA, EC, etc)
+
+# Legal
+
+[ssh-to-jwk.js](https://git.coolaj86.com/coolaj86/ssh-to-jwk.js) |
+MPL-2.0 |
+[Terms of Use](https://therootcompany.com/legal/#terms) |
+[Privacy Policy](https://therootcompany.com/legal/#privacy)
--- a/index.html
+++ b/index.html
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+<!DOCTYPE html>
+<html>
+<head>
+  <title>SSH Pub Parser - Bluecrypt</title>
+  <style>
+    textarea {
+      width: 42em;
+      height: 10em;
+    }
+  </style>
+</head>
+<body>
+  <h1>Bluecrypt SSH Public Key Parser</h1>
+
+  <textarea class="js-input" placeholder="Paste id_rsa.pub (or other SSH public key) here">ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCba21UHE+VbDTpmYYFZUOV+OQ8AngOCdjROsPC0KiEfMvEaEM3NQl58u6QL7G7QsErKViiNPm9OTFo6HF5JijfWzK7haHFuRMEsgI4VwIYyhvqlJDfw/wt0AiVvSmoMfEQn1p1aiaO4V/RJSE3Vw/uz2bxiT22uSkSqOyShyfYE6dMHnuoBkzr4jvSifT+INmbv6Nyo4+AAMCZtYeHLrsFeSTjLL9jMPjI4ZkVdlw2n3Xn9NbltF3/8Ao8dQfElqw+LIQWqU0oFHYNIP4ttfl5ObMKHaKSvBMyNruZR0El/ZsrcHLkAHRCLj07KRQJ81l5CUTPtQ02P1Eamz/nT4I3 root@localhost</textarea>
+
+  <pre><code class="js-hex"> </code></pre>
+
+  <pre><code class="js-jwk"> </code></pre>
+
+  <br>
+  <p>Made with <a href="https://git.coolaj86.com/coolaj86/bluecrypt-ssh-to-jwk.js/">ssh-to-jwk.js</a></p>
+
+  <script src="./ssh-to-jwk.js"></script>
+  <script>
+    'use strict';
+    Enc.bufToHex = function toHex(u8) {
+      var hex = [];
+      var i, h;
+      var len = (u8.byteLength || u8.length);
+
+      for (i = 0; i < len; i += 1) {
+        h = u8[i].toString(16);
+        if (h.length % 2) { h = '0' + h; }
+        hex.push(h);
+      }
+
+      return hex.join('').toLowerCase();
+    };
+
+    var $input = document.querySelector('.js-input');
+
+    function convert() {
+      console.log('keyup');
+      var ssh;
+
+      try {
+        var text = document.querySelector('.js-input').value.trim();
+        ssh = SSH.parse(text);
+        document.querySelector('.js-hex').innerText = ssh.elements.map(function (hex) {
+          return Enc.bufToHex(hex)
+            .match(/.{2}/g).join(' ')
+            .match(/.{1,24}/g).join(' ')
+            .match(/.{1,50}/g).join('\n');
+        }).join('\n\n')
+        document.querySelector('.js-jwk').innerText = JSON.stringify(ssh.jwk, null, 2);
+      } catch(e) {
+        ssh = { error: { message: e.message } };
+        document.querySelector('.js-hex').innerText = '';
+        document.querySelector('.js-jwk').innerText = JSON.stringify(ssh, null, 2);
+      }
+    }
+
+    $input.addEventListener('keyup', convert);
+    convert();
+  </script>
+</body>
+</html>
--- a/package.json
+++ b/package.json
@ -0,0 +1,28 @@
+{
+  "name": "bluecrypt-ssh-to-jwk",
+  "version": "1.0.0",
+  "description": "SSH to JWK in < 150 lines of VanillaJS.",
+  "homepage": "https://git.coolaj86.com/coolaj86/bluecrypt-ssh-to-jwk.js",
+  "main": "ssh-to-jwk.js",
+  "scripts": {
+    "prepare": "uglifyjs ssh-to-jwk.js > ssh-to-jwk.min.js"
+  },
+  "directories": {
+    "lib": "lib"
+  },
+  "repository": {
+    "type": "git",
+    "url": "https://git.coolaj86.com/coolaj86/bluecrypt-ssh-to-jwk.js"
+  },
+  "keywords": [
+    "zero-dependency",
+    "SSH-to-JWK",
+    "RSA",
+    "EC",
+    "SSH",
+    "JWK",
+    "ECDSA"
+  ],
+  "author": "AJ ONeal <coolaj86@gmail.com> (https://coolaj86.com/)",
+  "license": "MPL-2.0"
+}
--- a/ssh-to-jwk.js
+++ b/ssh-to-jwk.js
@ -0,0 +1,165 @@
+;(function (exports) {
+'use strict';
+
+if (!exports.Enc) { exports.Enc = {}; }
+if (!exports.SSH) { exports.SSH = {}; }
+
+var Enc = exports.Enc;
+var SSH = exports.SSH;
+
+SSH.parse = function (ssh) {
+  ssh = SSH.parseBlock(ssh);
+  ssh = SSH.parseElements(ssh);
+  //delete ssh.bytes;
+  return SSH.parsePublicKey(ssh);
+};
+
+SSH.parseBlock = function (ssh) {
+  ssh = ssh.split(/\s+/g);
+
+  return {
+    type: ssh[0]
+  , bytes: Enc.base64ToBuf(ssh[1])
+  , comment: ssh[2]
+  };
+};
+
+SSH.parseElements = function (ssh) {
+  var buf = ssh.bytes;
+  var fulllen = buf.byteLength || buf.length;
+  var offset = (buf.byteOffset || 0);
+  var i = 0;
+  var index = 0;
+  // using dataview to be browser-compatible (I do want _some_ code reuse)
+  var dv = new DataView(buf.buffer.slice(offset, offset + fulllen));
+  var els = [];
+  var el;
+  var len;
+
+  while (index < fulllen) {
+    i += 1;
+    if (i > 15) { throw new Error("15+ elements, probably not a public ssh key"); }
+    len = dv.getUint32(index, false);
+    index += 4;
+    el = buf.slice(index, index + len);
+    // remove BigUInt '00' prefix
+    if (0x00 === el[0]) {
+      el = el.slice(1);
+    }
+    els.push(el);
+    index += len;
+  }
+  if (fulllen !== index) {
+    throw new Error("invalid ssh public key length \n" + els.map(function (b) {
+      return Enc.bufToHex(b);
+    }).join('\n'));
+  }
+
+  ssh.elements = els;
+  return ssh;
+};
+
+SSH.parsePublicKey = function (ssh) {
+  var els = ssh.elements;
+  var typ = Enc.bufToBin(els[0]);
+  var len;
+
+  // RSA keys are all the same
+  if (SSH.types.rsa === typ) {
+    ssh.jwk = {
+      kty: 'RSA'
+    , n: Enc.bufToUrlBase64(els[2])
+    , e: Enc.bufToUrlBase64(els[1])
+    };
+    return ssh;
+  }
+
+  // EC keys are each different
+  if (SSH.types.p256 === typ) {
+    len = 32;
+    ssh.jwk = { kty: 'EC', crv: 'P-256' };
+  } else if (SSH.types.p384 === typ) {
+    len = 48;
+    ssh.jwk = { kty: 'EC', crv: 'P-384' };
+  } else {
+    throw new Error("Unsupported ssh public key type: "
+      + Enc.bufToBin(els[0]));
+  }
+
+  // els[1] is just a repeat of a subset of els[0]
+  var x = els[2].slice(1, 1 + len);
+  var y = els[2].slice(1 + len, 1 + len + len);
+
+  // I don't think EC keys use 0x00 padding, but just in case
+  if (0x00 === x[0]) { x = x.slice(1); }
+  if (0x00 === y[0]) { y = y.slice(1); }
+
+  ssh.jwk.x = Enc.bufToUrlBase64(x);
+  ssh.jwk.y = Enc.bufToUrlBase64(y);
+
+  return ssh;
+};
+
+SSH.types = {
+  // 19 '00000013'
+  // e c d s a - s h a 2 - n i s t p 2 5 6
+  // 65636473612d736861322d6e69737470323536
+  // 6e69737470323536
+  p256: 'ecdsa-sha2-nistp256'
+
+  // 19 '00000013'
+  // e c d s a - s h a 2 - n i s t p 3 8 4
+  // 65636473612d736861322d6e69737470333834
+  // 6e69737470323536
+, p384: 'ecdsa-sha2-nistp384'
+
+  // 7 '00000007'
+  // s s h - r s a
+  // 7373682d727361
+, rsa: 'ssh-rsa'
+};
+
+Enc.base64ToBuf = function (b64) {
+  return Enc.binToBuf(atob(b64));
+};
+
+Enc.binToBuf = function (bin) {
+  var arr = bin.split('').map(function (ch) {
+    return ch.charCodeAt(0);
+  });
+  return 'undefined' !== typeof Uint8Array ? new Uint8Array(arr) : arr;
+};
+
+Enc.bufToBase64 = function (u8) {
+  var bin = '';
+  u8.forEach(function (i) {
+    bin += String.fromCharCode(i);
+  });
+  return btoa(bin);
+};
+
+Enc.bufToBin = function (buf) {
+  var bin = '';
+  // cannot use .map() because Uint8Array would return only 0s
+  buf.forEach(function (ch) {
+    bin += String.fromCharCode(ch);
+  });
+  return bin;
+};
+
+Enc.bufToUrlBase64 = function (u8) {
+  return Enc.bufToBase64(u8)
+    .replace(/\+/g, '-').replace(/\//g, '_').replace(/=/g, '');
+};
+
+Enc.urlBase64ToBase64 = function urlsafeBase64ToBase64(str) {
+  var r = str % 4;
+  if (2 === r) {
+    str += '==';
+  } else if (3 === r) {
+    str += '=';
+  }
+  return str.replace(/-/g, '+').replace(/_/g, '/');
+};
+
+}('undefined' !== typeof window ? window : module.exports));
--- a/ssh-to-jwk.min.js
+++ b/ssh-to-jwk.min.js
@ -0,0 +1 @@
+(function(exports){"use strict";if(!exports.Enc){exports.Enc={}}if(!exports.SSH){exports.SSH={}}var Enc=exports.Enc;var SSH=exports.SSH;SSH.parse=function(ssh){ssh=SSH.parseBlock(ssh);ssh=SSH.parseElements(ssh);return SSH.parsePublicKey(ssh)};SSH.parseBlock=function(ssh){ssh=ssh.split(/\s+/g);return{type:ssh[0],bytes:Enc.base64ToBuf(ssh[1]),comment:ssh[2]}};SSH.parseElements=function(ssh){var buf=ssh.bytes;var fulllen=buf.byteLength||buf.length;var offset=buf.byteOffset||0;var i=0;var index=0;var dv=new DataView(buf.buffer.slice(offset,offset+fulllen));var els=[];var el;var len;while(index<fulllen){i+=1;if(i>15){throw new Error("15+ elements, probably not a public ssh key")}len=dv.getUint32(index,false);index+=4;el=buf.slice(index,index+len);if(0===el[0]){el=el.slice(1)}els.push(el);index+=len}if(fulllen!==index){throw new Error("invalid ssh public key length \n"+els.map(function(b){return Enc.bufToHex(b)}).join("\n"))}ssh.elements=els;return ssh};SSH.parsePublicKey=function(ssh){var els=ssh.elements;var typ=Enc.bufToBin(els[0]);var len;if(SSH.types.rsa===typ){ssh.jwk={kty:"RSA",n:Enc.bufToUrlBase64(els[2]),e:Enc.bufToUrlBase64(els[1])};return ssh}if(SSH.types.p256===typ){len=32;ssh.jwk={kty:"EC",crv:"P-256"}}else if(SSH.types.p384===typ){len=48;ssh.jwk={kty:"EC",crv:"P-384"}}else{throw new Error("Unsupported ssh public key type: "+Enc.bufToBin(els[0]))}var x=els[2].slice(1,1+len);var y=els[2].slice(1+len,1+len+len);if(0===x[0]){x=x.slice(1)}if(0===y[0]){y=y.slice(1)}ssh.jwk.x=Enc.bufToUrlBase64(x);ssh.jwk.y=Enc.bufToUrlBase64(y);return ssh};SSH.types={p256:"ecdsa-sha2-nistp256",p384:"ecdsa-sha2-nistp384",rsa:"ssh-rsa"};Enc.base64ToBuf=function(b64){return Enc.binToBuf(atob(b64))};Enc.binToBuf=function(bin){var arr=bin.split("").map(function(ch){return ch.charCodeAt(0)});return"undefined"!==typeof Uint8Array?new Uint8Array(arr):arr};Enc.bufToBase64=function(u8){var bin="";u8.forEach(function(i){bin+=String.fromCharCode(i)});return btoa(bin)};Enc.bufToBin=function(buf){var bin="";buf.forEach(function(ch){bin+=String.fromCharCode(ch)});return bin};Enc.bufToUrlBase64=function(u8){return Enc.bufToBase64(u8).replace(/\+/g,"-").replace(/\//g,"_").replace(/=/g,"")};Enc.urlBase64ToBase64=function urlsafeBase64ToBase64(str){var r=str%4;if(2===r){str+="=="}else if(3===r){str+="="}return str.replace(/-/g,"+").replace(/_/g,"/")}})("undefined"!==typeof window?window:module.exports);
			`@ -0,0 +1 @@`
			(function(exports){"use strict";if(!exports.Enc){exports.Enc={}}if(!exports.SSH){exports.SSH={}}var Enc=exports.Enc;var SSH=exports.SSH;SSH.parse=function(ssh){ssh=SSH.parseBlock(ssh);ssh=SSH.parseElements(ssh);return SSH.parsePublicKey(ssh)};SSH.parseBlock=function(ssh){ssh=ssh.split(/\s+/g);return{type:ssh[0],bytes:Enc.base64ToBuf(ssh[1]),comment:ssh[2]}};SSH.parseElements=function(ssh){var buf=ssh.bytes;var fulllen=buf.byteLength\|\|buf.length;var offset=buf.byteOffset\|\|0;var i=0;var index=0;var dv=new DataView(buf.buffer.slice(offset,offset+fulllen));var els=[];var el;var len;while(index<fulllen){i+=1;if(i>15){throw new Error("15+ elements, probably not a public ssh key")}len=dv.getUint32(index,false);index+=4;el=buf.slice(index,index+len);if(0===el[0]){el=el.slice(1)}els.push(el);index+=len}if(fulllen!==index){throw new Error("invalid ssh public key length \n"+els.map(function(b){return Enc.bufToHex(b)}).join("\n"))}ssh.elements=els;return ssh};SSH.parsePublicKey=function(ssh){var els=ssh.elements;var typ=Enc.bufToBin(els[0]);var len;if(SSH.types.rsa===typ){ssh.jwk={kty:"RSA",n:Enc.bufToUrlBase64(els[2]),e:Enc.bufToUrlBase64(els[1])};return ssh}if(SSH.types.p256===typ){len=32;ssh.jwk={kty:"EC",crv:"P-256"}}else if(SSH.types.p384===typ){len=48;ssh.jwk={kty:"EC",crv:"P-384"}}else{throw new Error("Unsupported ssh public key type: "+Enc.bufToBin(els[0]))}var x=els[2].slice(1,1+len);var y=els[2].slice(1+len,1+len+len);if(0===x[0]){x=x.slice(1)}if(0===y[0]){y=y.slice(1)}ssh.jwk.x=Enc.bufToUrlBase64(x);ssh.jwk.y=Enc.bufToUrlBase64(y);return ssh};SSH.types={p256:"ecdsa-sha2-nistp256",p384:"ecdsa-sha2-nistp384",rsa:"ssh-rsa"};Enc.base64ToBuf=function(b64){return Enc.binToBuf(atob(b64))};Enc.binToBuf=function(bin){var arr=bin.split("").map(function(ch){return ch.charCodeAt(0)});return"undefined"!==typeof Uint8Array?new Uint8Array(arr):arr};Enc.bufToBase64=function(u8){var bin="";u8.forEach(function(i){bin+=String.fromCharCode(i)});return btoa(bin)};Enc.bufToBin=function(buf){var bin="";buf.forEach(function(ch){bin+=String.fromCharCode(ch)});return bin};Enc.bufToUrlBase64=function(u8){return Enc.bufToBase64(u8).replace(/\+/g,"-").replace(/\//g,"_").replace(/=/g,"")};Enc.urlBase64ToBase64=function urlsafeBase64ToBase64(str){var r=str%4;if(2===r){str+="=="}else if(3===r){str+="="}return str.replace(/-/g,"+").replace(/_/g,"/")}})("undefined"!==typeof window?window:module.exports);