private static void ValidateExtendedSignParams(RawSignedModel model, SignParams @params)
{
ValidateSignParams(model, @params.SignerPrivateKey);
if (@params.Signer == null)
{
throw new ArgumentException($"{nameof(@params.Signer)} property is mandatory");
}
}
private static void ThrowExceptionIfSignatureExists(SignParams @params, IList <RawSignature> signatures)
{
if (signatures != null &&
((List <RawSignature>)signatures).Exists(
s => s.Signer == @params.Signer))
{
throw new VirgilException("The model already has this signature.");
}
}
/// <summary>
/// Adds signature to the specified <see cref="RawSignedModel"/> using specified signer
/// parameters included private key, signer type and additional raw bytes.
/// </summary>
/// <param name="model"> the instance of <see cref="RawSignedModel"/> to be signed.</param>
/// <param name="@params"> the instance of <see cref="SignParams"/> to sign with.</param>
/// <param name="signatureSnapshot"> Some additional raw bytes to be signed with model.</param>
public void Sign(RawSignedModel model, SignParams @params, byte[] signatureSnapshot = null)
{
ValidateExtendedSignParams(model, @params);
ThrowExceptionIfSignatureExists(@params, model.Signatures);
var extendedSnapshot = signatureSnapshot != null?
Bytes.Combine(model.ContentSnapshot, signatureSnapshot)
: model.ContentSnapshot;
var signatureBytes = Crypto.GenerateSignature(extendedSnapshot, @params.SignerPrivateKey);
var signature = new RawSignature
{
Signer = @params.Signer,
Signature = signatureBytes,
Snapshot = signatureSnapshot
};
model.Signatures.Add(signature);
}
/// <summary>
/// Adds signature to the specified <see cref="RawSignedModel"/> using specified signer
/// parameters included private key, signer type and dictionary with additional data.
/// </summary>
/// <param name="model"> the instance of <see cref="RawSignedModel"/> to be signed.</param>
/// <param name="@params"> the instance of <see cref="SignParams"/> to sign with.</param>
/// <param name="extraFields"> Dictionary with additional data to be signed with model.</param>
public void Sign(RawSignedModel model, SignParams @params, Dictionary <string, string> ExtraFields)
{
Sign(model, @params,
(ExtraFields != null) ? SnapshotUtils.TakeSnapshot(ExtraFields) : null
);
}