private static void secp256k1_ecdsa_recoverable_signature_save(secp256k1_ecdsa_recoverable_signature sig, secp256k1_scalar r, secp256k1_scalar s, byte recid)
{
if (secp256k1_scalar.Size == 32)
{
Util.Memcpy(r.d, 0, sig.data, 0, 32); // memcpy(&sig.data[0], r, 32);
Util.Memcpy(s.d, 0, sig.data, 32, 32); // memcpy(&sig->data[32], s, 32);
}
else
{
Scalar.secp256k1_scalar_get_b32(sig.data, 0, r);
Scalar.secp256k1_scalar_get_b32(sig.data, 32, s);
}
sig.data[64] = recid;
}
private static bool secp256k1_ecdsa_sign_recoverable(secp256k1_context ctx, secp256k1_ecdsa_recoverable_signature signature,
byte[] msg32, byte[] seckey, secp256k1_nonce_function noncefp, byte[] noncedata)
{
if (ctx == null || msg32 == null || signature == null || seckey == null)
{
throw new NullReferenceException();
}
if (!ECMultGen.secp256k1_ecmult_gen_context_is_built(ctx.ecmult_gen_ctx))
{
throw new ArithmeticException();
}
if (noncefp == null)
{
noncefp = Secp256k1.secp256k1_nonce_function_default;
}
secp256k1_scalar r, s;
secp256k1_scalar sec, non, msg;
byte recid = 1;
bool ret = false;
var overflow = false;
sec = new secp256k1_scalar();
Scalar.secp256k1_scalar_set_b32(sec, seckey, ref overflow);
r = new secp256k1_scalar();
s = new secp256k1_scalar();
/* Fail if the secret key is invalid. */
if (!overflow && !Scalar.secp256k1_scalar_is_zero(sec))
{
var nonce32 = new byte[32];
uint count = 0;
msg = new secp256k1_scalar();
Scalar.secp256k1_scalar_set_b32(msg, msg32);
non = new secp256k1_scalar();
while (true)
{
ret = noncefp(nonce32, msg32, seckey, null, noncedata, count);
if (!ret)
{
break;
}
Scalar.secp256k1_scalar_set_b32(non, nonce32, ref overflow);
if (!Scalar.secp256k1_scalar_is_zero(non) && !overflow)
{
if (secp256k1_ecdsa_sig_sign(ctx.ecmult_gen_ctx, r, s, sec, msg, non, out recid))
{
break;
}
}
count++;
}
Util.MemSet(nonce32, 0, 32); //memset(nonce32, 0, 32);
Scalar.secp256k1_scalar_clear(msg);
Scalar.secp256k1_scalar_clear(non);
Scalar.secp256k1_scalar_clear(sec);
}
if (ret)
{
secp256k1_ecdsa_recoverable_signature_save(signature, r, s, recid);
}
else
{
Util.MemSet(signature.data, 0, secp256k1_ecdsa_recoverable_signature.Size); //memset(signature, 0, sizeof(* signature));
}
return(ret);
}