/// <summary>
/// Unpack and verify signed data before casting it to the supplied type.
/// </summary>
/// <typeparam name="T">Type in which to cast the result to.</typeparam>
/// <param name="decorator">Signature decorator to unpack and verify</param>
/// <returns>Resulting data cast to type T.</returns>
public static T UnpackAndVerifyData <T>(SignatureDecorator decorator)
{
var sigDataBytes = decorator.SignatureData.GetBytesFromBase64();
var sigDataString = sigDataBytes.Skip(8).ToArray().GetUTF8String();
return(JsonConvert.DeserializeObject <T>(sigDataString));
}
/// <summary>
/// Unpack and verify signed data before casting it to the supplied type.
/// </summary>
/// <typeparam name="T">Type in which to cast the result to.</typeparam>
/// <param name="decorator">Signature decorator to unpack and verify</param>
/// <returns>Resulting data cast to type T.</returns>
public static async Task <T> UnpackAndVerifyAsync <T>(SignatureDecorator decorator)
{
if (await Crypto.VerifyAsync(
theirVk: decorator.Signer,
message: decorator.SignatureData.GetBytesFromBase64(),
signature: decorator.Signature.GetBytesFromBase64()))
{
var sigDataBytes = decorator.SignatureData.GetBytesFromBase64();
var sigDataString = sigDataBytes.Skip(8).ToArray().GetUTF8String();
return(sigDataString.ToObject <T>());
}
throw new AriesFrameworkException(ErrorCode.InvalidMessage, "The signed payload was invalid");
}
/// <summary>
/// Sign data supplied and return a signature decorator.
/// </summary>
/// <typeparam name="T">Data object type to sign.</typeparam>
/// <param name="agentContext">Agent context.</param>
/// <param name="data">Data to sign.</param>
/// <param name="signerKey">Signers verkey.</param>
/// <returns>Async signature decorator.</returns>
public static async Task <SignatureDecorator> SignData <T>(IAgentContext agentContext, T data, string signerKey)
{
var dataJson = JsonConvert.SerializeObject(data);
var epocData = new byte[8]; //TODO actually put the epoc representation in here
var sigData = epocData.Concat(dataJson.GetUTF8Bytes()).ToArray();
var sig = await Crypto.SignAsync(agentContext.Wallet, signerKey, sigData);
var sigDecorator = new SignatureDecorator
{
SignatureType = DefaultSignatureType,
SignatureData = sigData.ToBase64UrlString(),
Signature = sig.ToBase64UrlString(),
Signer = signerKey
};
return(sigDecorator);
}
/// <summary>
/// Sign data supplied and return a signature decorator.
/// </summary>
/// <typeparam name="T">Data object type to sign.</typeparam>
/// <param name="agentContext">Agent context.</param>
/// <param name="data">Data to sign.</param>
/// <param name="signerKey">Signers verkey.</param>
/// <returns>Async signature decorator.</returns>
public static async Task <SignatureDecorator> SignDataAsync <T>(IAgentContext agentContext, T data, string signerKey)
{
var dataJson = data.ToJson();
var epochData = BitConverter.GetBytes(DateTimeOffset.UtcNow.ToUnixTimeSeconds());
var sigData = epochData.Concat(dataJson.GetUTF8Bytes()).ToArray();
var sig = await Crypto.SignAsync(agentContext.Wallet, signerKey, sigData);
var sigDecorator = new SignatureDecorator
{
SignatureType = DefaultSignatureType,
SignatureData = sigData.ToBase64UrlString(),
Signature = sig.ToBase64UrlString(),
Signer = signerKey
};
return(sigDecorator);
}
