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Translate between JOSE and ASN.1/DER encodings for ECDSA signatures


npm install ecdsa-sig-formatter --save


var format = require('ecdsa-sig-formatter');

var derSignature = '..'; // asn.1/DER encoded ecdsa signature

var joseSignature = format.derToJose(derSignature);


.derToJose(Buffer|String signature, String alg) -> String

Convert the ASN.1/DER encoded signature to a JOSE-style concatenated signature. Returns a base64 url encoded String.

.joseToDer(Buffer|String signature, String alg) -> Buffer

Convert the JOSE-style concatenated signature to an ASN.1/DER encoded signature. Returns a Buffer


  1. Fork the repository. Committing directly against this repository is highly discouraged.

  2. Make your modifications in a branch, updating and writing new unit tests as necessary in the spec directory.

  3. Ensure that all tests pass with npm test

  4. rebase your changes against master. Do not merge.

  5. Submit a pull request to this repository. Wait for tests to run and someone to chime in.

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