Convert x509 DER encoded to PEM

[jfromaniello]

Hi, I am looking for a way to convert from DER to PEM, the equivalent of

openssl x509 -in test.der -inform DER -pubkey -subject

[dlongley]

Using the public key specific API (which will set the appropriate PEM headers for you), the code looks about like this:

var forge = require('forge');
var fs = require('fs');

var der = fs.readFileSync('/publickey.der', {encoding: 'binary'});
var asn1 = forge.asn1.fromDer(der);
var publicKey = forge.pki.publicKeyFromAsn1(asn1);
var pem = forge.pki.publicKeyToPem(publicKey);

Doing generic DER to PEM, where you must set the PEM headers, etc.:

var forge = require('forge');
var fs = require('fs');

var der = fs.readFileSync('/publickey.der', {encoding: 'binary'});

var msg = {
  type: 'PUBLIC KEY', // you specify this header for the data
  body: der
};
var pem = forge.pem.encode(msg);

[jfromaniello]

Thank you very much, it works like a charm!

[dlongley]

Sure :)