/// <summary>
/// Create a blinded commitment of messages for use in producing a blinded BBS+ signature
/// </summary>
/// <param name="request">Request for producing the blinded commitment</param>
/// <returns></returns>
public static BlindedCommitment CreateBlindedCommitment(CreateBlindedCommitmentRequest request)
{
using var context = new UnmanagedMemoryContext();
var handle = Native.bbs_blind_commitment_context_init(out var error);
context.ThrowIfNeeded(error);
foreach (var item in request.Messages)
{
Native.bbs_blind_commitment_context_add_message_string(handle, item.Index, item.Message, out error);
context.ThrowIfNeeded(error);
}
Native.bbs_blind_commitment_context_set_nonce_string(handle, request.Nonce, out error);
context.ThrowIfNeeded(error);
Native.bbs_blind_commitment_context_set_public_key(handle, context.ToBuffer(request.PublicKey), out error);
context.ThrowIfNeeded(error);
Native.bbs_blind_commitment_context_finish(handle, out var commitment, out var outContext, out var blindingFactor, out error);
context.ThrowIfNeeded(error);
return(new BlindedCommitment(context.ToByteArray(outContext), context.ToByteArray(blindingFactor), context.ToByteArray(commitment)));
}
/// <summary>
/// Creates the proof asynchronous.
/// </summary>
/// <param name="myKey">My key.</param>
/// <param name="nonce">The nonce.</param>
/// <param name="messages">The messages.</param>
/// <returns></returns>
public static byte[] CreateProof(CreateProofRequest proofRequest)
{
using var context = new UnmanagedMemoryContext();
var handle = Native.bbs_create_proof_context_init(out var error);
context.ThrowIfNeeded(error);
foreach (var message in proofRequest.Messages)
{
Native.bbs_create_proof_context_add_proof_message_string(handle, message.Message, message.ProofType, context.ToBuffer(proofRequest.BlindingFactor ?? Array.Empty <byte>()), out error);
context.ThrowIfNeeded(error);
}
Native.bbs_create_proof_context_set_nonce_string(handle, proofRequest.Nonce, out error);
context.ThrowIfNeeded(error);
Native.bbs_create_proof_context_set_public_key(handle, context.ToBuffer(proofRequest.PublicKey), out error);
context.ThrowIfNeeded(error);
Native.bbs_create_proof_context_set_signature(handle, context.ToBuffer(proofRequest.Signature), out error);
context.ThrowIfNeeded(error);
Native.bbs_create_proof_context_finish(handle, out var proof, out error);
context.ThrowIfNeeded(error);
return(context.ToByteArray(proof));
}
/// <summary>
/// Signs a set of messages featuring both known and blinded messages to the signer and produces a BBS+ signature
/// </summary>
/// <param name="keyPair">The signing key containing the secret BLS key.</param>
/// <param name="commitment">The commitment.</param>
/// <param name="messages">The messages.</param>
/// <returns></returns>
public static byte[] BlindSign(BlindSignRequest request)
{
using var context = new UnmanagedMemoryContext();
var handle = Native.bbs_blind_sign_context_init(out var error);
context.ThrowIfNeeded(error);
foreach (var item in request.Messages)
{
Native.bbs_blind_sign_context_add_message_string(handle, item.Index, item.Message, out error);
context.ThrowIfNeeded(error);
}
Native.bbs_blind_sign_context_set_public_key(handle, context.ToBuffer(request.PublicKey), out error);
context.ThrowIfNeeded(error);
Native.bbs_blind_sign_context_set_secret_key(handle, context.ToBuffer(request.SecretKey.SecretKey.ToArray()), out error);
context.ThrowIfNeeded(error);
Native.bbs_blind_sign_context_set_commitment(handle, context.ToBuffer(request.Commitment), out error);
context.ThrowIfNeeded(error);
Native.bbs_blind_sign_context_finish(handle, out var blindedSignature, out error);
context.ThrowIfNeeded(error);
return(context.ToByteArray(blindedSignature));
}
/// <summary>
/// Signs a set of messages with a BBS key pair and produces a BBS signature
/// </summary>
/// <param name="signRequest">Request for the sign operation</param>
/// <returns>The raw signature value</returns>
/// <exception cref="BbsException">
/// Secret key not found
/// or
/// Messages cannot be null
/// </exception>
public static byte[] Sign(SignRequest signRequest)
{
if (signRequest?.KeyPair?.SecretKey is null) throw new BbsException("Secret key not found");
if (signRequest?.Messages is null) throw new BbsException("Messages cannot be null");
var bbsKeyPair = signRequest.KeyPair.GeyBbsKeyPair((uint)signRequest.Messages.Length);
using var context = new UnmanagedMemoryContext();
var handle = Native.bbs_sign_context_init(out var error);
context.ThrowIfNeeded(error);
foreach (var message in signRequest.Messages)
{
Native.bbs_sign_context_add_message_string(handle, message, out error);
context.ThrowIfNeeded(error);
}
Native.bbs_sign_context_set_public_key(handle, context.ToBuffer(bbsKeyPair.PublicKey), out error);
context.ThrowIfNeeded(error);
Native.bbs_sign_context_set_secret_key(handle, context.ToBuffer(signRequest.KeyPair.SecretKey!), out error);
context.ThrowIfNeeded(error);
Native.bbs_sign_context_finish(handle, out var signature, out error);
context.ThrowIfNeeded(error);
return context.ToByteArray(signature);
}
/// <summary>
/// Unblinds the signature asynchronous.
/// </summary>
/// <param name="request">Unbling signature request</param>
/// <returns></returns>
public static byte[] UnblindSignature(UnblindSignatureRequest request)
{
using var context = new UnmanagedMemoryContext();
Native.bbs_unblind_signature(context.ToBuffer(request.BlindedSignature), context.ToBuffer(request.BlindingFactor), out var unblindedSignature, out var error);
context.ThrowIfNeeded(error);
return(context.ToByteArray(unblindedSignature));
}
/// <summary>
/// Generates new BBS+ public key from the current BLS12-381
/// </summary>
/// <param name="messageCount">The message count.</param>
/// <returns></returns>
public BbsKeyPair GeyBbsKeyPair(uint messageCount)
{
using var context = new UnmanagedMemoryContext();
if (SecretKey is null)
{
Native.bls_public_key_to_bbs_key(context.ToBuffer(PublicKey), messageCount, out var publicKey, out var error);
context.ThrowIfNeeded(error);
return(new BbsKeyPair(context.ToByteArray(publicKey), messageCount));
}
else
{
Native.bls_secret_key_to_bbs_key(context.ToBuffer(SecretKey), messageCount, out var publicKey, out var error);
context.ThrowIfNeeded(error);
return(new BbsKeyPair(context.ToByteArray(publicKey), messageCount));
}
}
