using Org.BouncyCastle.Asn1.Oiw; using Org.BouncyCastle.Asn1.X509; using Org.BouncyCastle.Utilities; using System; namespace Org.BouncyCastle.Asn1.Pkcs { public class RsaesOaepParameters : Asn1Encodable { private AlgorithmIdentifier hashAlgorithm; private AlgorithmIdentifier maskGenAlgorithm; private AlgorithmIdentifier pSourceAlgorithm; public static readonly AlgorithmIdentifier DefaultHashAlgorithm = new AlgorithmIdentifier(OiwObjectIdentifiers.IdSha1, DerNull.Instance); public static readonly AlgorithmIdentifier DefaultMaskGenFunction = new AlgorithmIdentifier(PkcsObjectIdentifiers.IdMgf1, DefaultHashAlgorithm); public static readonly AlgorithmIdentifier DefaultPSourceAlgorithm = new AlgorithmIdentifier(PkcsObjectIdentifiers.IdPSpecified, new DerOctetString(new byte[0])); public AlgorithmIdentifier HashAlgorithm => hashAlgorithm; public AlgorithmIdentifier MaskGenAlgorithm => maskGenAlgorithm; public AlgorithmIdentifier PSourceAlgorithm => pSourceAlgorithm; public static RsaesOaepParameters GetInstance(object obj) { if (obj is RsaesOaepParameters) return (RsaesOaepParameters)obj; if (obj is Asn1Sequence) return new RsaesOaepParameters((Asn1Sequence)obj); throw new ArgumentException("Unknown object in factory: " + Platform.GetTypeName(obj), "obj"); } public RsaesOaepParameters() : this(DefaultHashAlgorithm, DefaultMaskGenFunction, DefaultPSourceAlgorithm) { } public RsaesOaepParameters(AlgorithmIdentifier hashAlgorithm, AlgorithmIdentifier maskGenAlgorithm) : this(hashAlgorithm, maskGenAlgorithm, DefaultPSourceAlgorithm) { } public RsaesOaepParameters(AlgorithmIdentifier hashAlgorithm, AlgorithmIdentifier maskGenAlgorithm, AlgorithmIdentifier pSourceAlgorithm) { this.hashAlgorithm = hashAlgorithm; this.maskGenAlgorithm = maskGenAlgorithm; this.pSourceAlgorithm = pSourceAlgorithm; } public RsaesOaepParameters(Asn1Sequence seq) { hashAlgorithm = DefaultHashAlgorithm; maskGenAlgorithm = DefaultMaskGenFunction; pSourceAlgorithm = DefaultPSourceAlgorithm; for (int i = 0; i != seq.Count; i++) { Asn1TaggedObject asn1TaggedObject = (Asn1TaggedObject)seq[i]; switch (asn1TaggedObject.TagNo) { case 0: hashAlgorithm = AlgorithmIdentifier.GetInstance(asn1TaggedObject, true); break; case 1: maskGenAlgorithm = AlgorithmIdentifier.GetInstance(asn1TaggedObject, true); break; case 2: pSourceAlgorithm = AlgorithmIdentifier.GetInstance(asn1TaggedObject, true); break; default: throw new ArgumentException("unknown tag"); } } } public override Asn1Object ToAsn1Object() { Asn1EncodableVector asn1EncodableVector = new Asn1EncodableVector(3); if (!hashAlgorithm.Equals(DefaultHashAlgorithm)) asn1EncodableVector.Add(new DerTaggedObject(true, 0, hashAlgorithm)); if (!maskGenAlgorithm.Equals(DefaultMaskGenFunction)) asn1EncodableVector.Add(new DerTaggedObject(true, 1, maskGenAlgorithm)); if (!pSourceAlgorithm.Equals(DefaultPSourceAlgorithm)) asn1EncodableVector.Add(new DerTaggedObject(true, 2, pSourceAlgorithm)); return new DerSequence(asn1EncodableVector); } } }