This is a little utility, which parses OpenSSH RSA public keys in pure javascript and returns modulus n and exponent e.
It can be applied to parse public keys generated for example by the ssh-keygen command line tool:
ssh-keygen -t rsa -b 4096 -C "some comment"
The implementation is based on http://blog.oddbit.com/2011/05/08/converting-openssh-public-keys/ and https://github.com/PatrickRoumanoff/js-keygen
Simply install the npm package:
npm i opensshpubkeyparser
and require the module:
var parser = require('opensshpubkeyparser');
An example can be found in node_sample.js.
Before running it, make sure to execute npm install in the root directory containing package.json to resolve required devDependencies.
To run the example, simply execute npm start.
For in-browser use, simply import the parser.js file from html and remove the first line from the parser.js file:
module.exports = {parsePublicKey};
An example can be found in index.html.