public void Ed25519_precompile_can_verify_correct_sig()
{
HashProvider hashProvider = new HashProvider(HashingAlgorithm.GetAlgorithmMetadata("blake2b-256"));
FfiWrapper cryptoContext = new FfiWrapper();
IPrivateKey signingPrivateKey = cryptoContext.GeneratePrivateKey();
var signingPublicKeyBytes = signingPrivateKey.GetPublicKey().Bytes;
var byteCode = PrepareEd25519PrecompileCall(hashProvider, cryptoContext, signingPrivateKey, signingPrivateKey);
GethLikeTxTracer txTracer = RunVirtualMachine(byteCode);
EthereumJsonSerializer serializer = new EthereumJsonSerializer();
GethLikeTxTrace trace = txTracer.BuildResult();
TestContext.WriteLine(serializer.Serialize(trace, true));
trace.Entries.Last().Stack.First().Should().Be("0000000000000000000000000000000000000000000000000000000000000001");
trace.Entries.Last().Memory.First().Should().StartWith("01");
}
private byte[] PrepareEd25519PrecompileCall(HashProvider hashProvider, FfiWrapper cryptoContext, IPrivateKey signingPrivateKey, IPrivateKey otherPrivateKey)
{
var data = Encoding.UTF8.GetBytes("Testing testing 1 2 3");
var message = hashProvider.ComputeMultiHash(data).Digest;
var signingContext = Encoding.UTF8.GetBytes("Testing testing 1 2 3 context");
var context = hashProvider.ComputeMultiHash(signingContext).Digest;
ISignature signature = cryptoContext.Sign(signingPrivateKey, message, context);
var signatureBytes = signature.SignatureBytes;
var publicKeyBytes = otherPrivateKey.GetPublicKey().Bytes;
// below verify check is not needed but allows for greater confidence for any person in the future
// that would approach and debug test when it goes wrong
// =====================================================
cryptoContext.Verify(signature, message, context)
.Should().BeTrue("signature generated with private key should verify with corresponding public key");
// =====================================================
// save message hash in memory at position 0x00
string pushToMemoryAt0 = "7f" + message.ToHexString(false) + "600052";
// save first 32 bytes of the sig in memory starting from position 0x20
string pushToMemoryAt32 = "7f" + signatureBytes.AsSpan(0, 32).ToHexString(false) + "602052";
// save remaining 32 bytes of the sig in memory starting from position 0x40
string pushToMemoryAt64 = "7f" + signatureBytes.AsSpan(32, 32).ToHexString(false) + "604052";
// save context bytes in memory starting from position 0x60 (but this should be changed if context is smaller)
string pushToMemoryAt96 = "7f" + context.ToHexString(false) + "606052";
// save public key bytes in memory starting from position 0x80 (but this should be changed if context is smaller)
string pushToMemoryAt128 = "7f" + publicKeyBytes.ToHexString(false) + "608052";
// address of the precompile within Catalyst
string addressCode = GetEd25519PrecompileAddressAsHex();
var byteCode = Bytes.FromHexString(
pushToMemoryAt0 +
pushToMemoryAt32 +
pushToMemoryAt64 +
pushToMemoryAt96 +
pushToMemoryAt128 +
// PUSH1 32 PUSH1 0 PUSH1 160 PUSH1 0 PUSH20 address GAS STATICCALL
// make a call to precompile and pass [0,160) bytes of memory as an input
// and store result at [0,1) of memory array
// allow precompile to use all the gas required
"6001600060a0600073" +
addressCode +
"45fa00");
TestContext.WriteLine(byteCode.ToHexString());
return(byteCode);
}