signature is not canonical

[t3ran13]

is it woking, did you check? blockchain tells it is not canonical

[ldudzsim]

If you talking about this and forcing to use smaller s value in signature, we do not have it, because our lib is strict elliptic math, without implementation focused on bitcoin/blockchain or something. But if you need that, you can check this

<?php

require_once("vendor/autoload.php");

use Elliptic\EC;
use Elliptic\EC\Signature;

function getNegativeSignature($ec, $sig) {
    $res = new Signature($sig);
    $res->s = $res->s->neg()->add($ec->n);
    return $res;
}

$ec = new EC('secp256k1');
$key = $ec->genKeyPair();
$msg = 'ab4c3451';
$signature = $key->sign($msg);
$negativeSignature = getNegativeSignature($ec, $signature);

echo "Normal signature:   " . $signature->toDER('hex') . "\n";
echo "Negative signature: " . $negativeSignature->toDER('hex') . "\n";

echo "Verify normal:   " . (($key->verify($msg, $signature) == TRUE) ? "true" : "false") . "\n";
echo "Verify negative: " . (($key->verify($msg, $negativeSignature) == TRUE) ? "true" : "false") . "\n";

if ($signature->s->cmp($negativeSignature->s) < 0) {
    echo "Normal is canonical\n";
}
else {
    echo "Negative is canonical\n";
}

[t3ran13]

sorry, it is work correct, i forgot make hash of message #21

canonical sign can be checked with DER

    public static function isSignatureCanonical($der)
    {
        $buffer = new ByteBuffer();
        $buffer->write($der);
        $lenR = $buffer->readInt8(3);
        $lenS = $buffer->readInt8(5 + $lenR);

        return $lenR === 32 && $lenS === 32;
    }

run sign one more time in loop if it is not canonical

[ldudzsim]

ok