Dart Requires Chilkat v11.0.0+

Generate ECDSA Key and Get Details as XML

See more ECC Examples

Demonstrates how to generate an ECDSA key and gets the parts as XML. Dart

import 'package:chilkat/chilkat.dart';

void main() {
  // This requires the Chilkat API to have been previously unlocked.
  // See Global Unlock Sample for sample code.

  final ecc = CkEcc();

  // Generate a random ECC private key on the secp256k1 curve.
  // Chilkat also supports other curves, such as secp384r1, secp521r1, and secp256r1.

  // Create a Fortuna PRNG and seed it with system entropy.
  // This will be our source of random data for generating the ECC private key.
  final fortuna = CkPrng();
  final entropy = fortuna.getEntropy(32, 'base64');
  fortuna.addEntropy(entropy, 'base64');

  final privKey = CkPrivateKey();
  try {
    ecc.genKey('secp256k1', fortuna, privKey);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // An EC private key has this ASN.1
  // ECPrivateKey ::= SEQUENCE {
  //     version        INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1),
  //     privateKey     OCTET STRING,
  //     parameters [0] ECParameters {{ NamedCurve }} OPTIONAL,
  //     publicKey  [1] BIT STRING OPTIONAL (This is the ANSI X9.63 public key format.)

  final asn = CkAsn();
  try {
    asn.loadEncoded(privKey.getPkcs1ENC('base64'), 'base64');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  final xml = CkXml();
  xml.loadXml(asn.asnToXml());

  print(xml.getXml());

  // The XML looks like this:
  // <?xml version="1.0" encoding="utf-8" ?>
  // <sequence>
  //     <int>01</int>
  //     <octets>JgJvBG+3wletkJab8iXAkpz0O8/AgWZSpkYVcB7SpnU=</octets>
  //     <contextSpecific tag="0" constructed="1">
  //         <oid>1.3.132.0.10</oid>
  //     </contextSpecific>
  // </sequence>

  // The 32-byte private key is in the octets..
  // Get it as hex.
  final crypt = CkCrypt2();
  final privKeyHex = crypt.reEncode(xml.getChildContent('octets'), 'base64', 'hex');

  print('EC private key as hex = $privKeyHex');
}