using Org.BouncyCastle.Utilities; using System; namespace Org.BouncyCastle.Asn1.Nist { public class KMacWithShake256Params : Asn1Encodable { private static readonly byte[] EMPTY_STRING = new byte[0]; private static readonly int DEF_LENGTH = 512; private readonly int outputLength; private readonly byte[] customizationString; public int OutputLength => outputLength; public byte[] CustomizationString => Arrays.Clone(customizationString); public KMacWithShake256Params(int outputLength) { this.outputLength = outputLength; customizationString = EMPTY_STRING; } public KMacWithShake256Params(int outputLength, byte[] customizationString) { this.outputLength = outputLength; this.customizationString = Arrays.Clone(customizationString); } public static KMacWithShake256Params GetInstance(object o) { if (o is KMacWithShake256Params) return (KMacWithShake256Params)o; if (o != null) return new KMacWithShake256Params(Asn1Sequence.GetInstance(o)); return null; } private KMacWithShake256Params(Asn1Sequence seq) { if (seq.Count > 2) throw new InvalidOperationException("sequence size greater than 2"); if (seq.Count == 2) { outputLength = DerInteger.GetInstance(seq[0]).IntValueExact; customizationString = Arrays.Clone(Asn1OctetString.GetInstance(seq[1]).GetOctets()); } else if (seq.Count == 1) { DerInteger derInteger = seq[0] as DerInteger; if (derInteger != null) { outputLength = derInteger.IntValueExact; customizationString = EMPTY_STRING; } else { outputLength = DEF_LENGTH; customizationString = Arrays.Clone(Asn1OctetString.GetInstance(seq[0]).GetOctets()); } } else { outputLength = DEF_LENGTH; customizationString = EMPTY_STRING; } } public override Asn1Object ToAsn1Object() { Asn1EncodableVector asn1EncodableVector = new Asn1EncodableVector(2); if (outputLength != DEF_LENGTH) asn1EncodableVector.Add(new DerInteger(outputLength)); if (customizationString.Length != 0) asn1EncodableVector.Add(new DerOctetString(CustomizationString)); return new DerSequence(asn1EncodableVector); } } }