Got 'undefined' when using this library.

[hustshawn]

Hi, I tried your library, and used your example code, but got undefined result instead of a JWK.

I want a JWK only contains my Public key, so I runned your code as

var fs = require('fs');
var rsaPemToJWK = require('rsa-pem-to-jwk');

var pem = fs.readFileSync('pubk.pem');
var JWK = rsaPemToJWK(pem, {use: 'sig'}, 'public');
console.log(JWK)  // undefined

Here is my PUBLIC key(the content of pubk.pem).

-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAwp6e3ABsGZGTjqmUWIGP
99cXucPOoM0sbc2wxdxrXCahlqKRvxcjl+QyCQOZC3Ff3BKI0B7PF+XiU1gcbqXE
r942MlVs6GIbohPF98BIxaUX/nJFDziABfDAQ/EDTpsSJIaE/UhhoWdTjU/XG5nz
4dQZWTKaw7SdD2EvjH+4uG1KbyOavLeeqjrItItIEedHeaXYSIy7P+6N+yZ6qYkW
ALnpm+Lqi0sxrPZDuiQ5Bq4bdYvaKOMBxbHzah5FOZF3bxPLVBjzOH0PtxvUdgLk
9sQ1Hl3k5LbEPrbG709ssEjO5pKJZwx21M6yrxAIZJjLLz6t81s/e0Lx55kTu4h9
QwIDAQAB
-----END PUBLIC KEY-----

Any ideas about this ?

[modu]

I am facing exactly the same issue. I tried using 'private' in place of 'public' for generating var JWK. Same issue.

[hustshawn]

Hey @modu, I found another Python package to generate JWK and it works.
http://jwcrypto.readthedocs.io/en/latest/jwk.html#examples

[abalmos]

This library only supports the RSAPublicKey format. More info can be found here https://github.com/OADA/rsa-pem-to-jwk/blob/master/README.md#pem-format

You should think about using a better implementation as this project uses a quick hack. Since we wrote this pem-jwk was released. It uses asn1.js to read pem files with more success. We now use pem-jwk in our projects.

[steowens]

Yea this project is broken.

[mattbrictson]

Make sure there is a newline at the end of your PEM block. It took a few tries but that seemed to be the trick. This works for me:

const rsaPemToJwk = require("rsa-pem-to-jwk");
const pem = `-----BEGIN RSA PRIVATE KEY-----
...
...
...
-----END RSA PRIVATE KEY-----
`;
rsaPemToJwk(pem, {use: "sig"}, "public");
// => { kty: 'RSA', use: 'sig', ... }

[tncowart]

Instead of -----BEGIN PUBLIC KEY----- and -----END PUBLIC KEY----- you have to have -----BEGIN RSA PUBLIC KEY----- and -----END RSA PUBLIC KEY-----

[ghost]

Fixed in #6.

[DamianGuilisasti]

A possible solution could be to add a new line at the end of the PEM file:

  const privateKey = fs.readFileSync(`${__dirname}/../../certs/private.pem`);

  const certString = privateKey.toString("binary"); //Convert from buffer to string

  const cert = certString + "\n"; //Add a new line at the end of the file

  const jwk = rsaPemToJwk(cert, { use: "sig" }, "public");

console.log(jwk);

[jasonycw]

Seems like this library is using a very old outdated package (https://www.npmjs.com/package/rsa-unpack)
And the expected private key must start with ----BEGIN RSA (PRIVATE|PUBLIC) KEY-----
I made this library works with private key generated with

ssh-keygen -t rsa -b 2048 -m PEM -f private.pem

But not with openssl, since the key started with -----BEGIN PRIVATE KEY----- or -----BEGIN ENCRYPTED PRIVATE KEY-----

[mfechner]

This library only supports the RSAPublicKey format. More info can be found here https://github.com/OADA/rsa-pem-to-jwk/blob/master/README.md#pem-format

You should think about using a better implementation as this project uses a quick hack. Since we wrote this pem-jwk was released. It uses asn1.js to read pem files with more success. We now use pem-jwk in our projects.

You should maybe make this clear in the README.md that it is better to use pem-jwk then this lib. This will save many people a lot of time.