adds support for brainpoolP256r1

[robertboeser]

Target branch: 4.2.x

• It is a Bug fix
• It is a New feature
• It is related to dependencies

Includes:

• Breaks BC
• Deprecations

I needed support for the brainpool curve, so I added support for it. Maybe it is useful for somebody else, too.

[Spomky]

Thank you.
Please let me have some time to review it carefully.

[Spomky]

Hi @robertboeser,

Please fix the issues I spotted.
Also, would you mind adding some tests to confirm:

• BP-256 key creation
• PEM import/export to check the OID
• OpenSSL compatibility

Many thanks.
Regards.

[Spomky]

This is not correct as the OID is different for BP public keys

[Spomky]

Should be as follows:

  private static function bp256PublicKey(): string
  {
      return pack(
          'H*',
          '305a' // SEQUENCE, length 90
          . '3014' // SEQUENCE, length 20
          . '0607' // OID, length 7
          . '2a8648ce3d0201' // 1.2.840.10045.2.1 = EC Public Key
          . '0609' // OID, length 9
          . '2b2403030208010107' // 1.3.36.3.3.2.8.1.1.7 = brainpoolP256r1
          . '0342' // BIT STRING, length 66
          . '00' // prepend with NUL
      );
  }

[Spomky]

Same here. The OID is different for BP private keys

[Spomky]

Should be as follows:

  private static function bp256PrivateKey(JWK $jwk): string
  {
      $d = $jwk->get('d');
      if (!is_string($d)) {
          throw new InvalidArgumentException('Unable to get the private key');
      }
      $d = unpack('H*', str_pad(Base64UrlSafe::decodeNoPadding($d), 32, "\0", STR_PAD_LEFT));
      if (!is_array($d) || !isset($d[1])) {
          throw new InvalidArgumentException('Unable to get the private key');
      }

      return pack(
          'H*',
          '3078' // SEQUENCE, length 120
          . '020101' // INTEGER, 1
          . '0420' // OCTET STRING, length 32
          . $d[1]
          . 'a00b' // TAGGED OBJECT #0, length 11
          . '0609' // OID, length 9
          . '2b2403030208010107' // 1.3.36.3.3.2.8.1.1.7
          . 'a144' // TAGGED OBJECT #1, length 68
          . '0342' // BIT STRING, length 66
          . '00'
      );
  }