RsaDigestSigner
using Org.BouncyCastle.Asn1;
using Org.BouncyCastle.Asn1.Nist;
using Org.BouncyCastle.Asn1.Pkcs;
using Org.BouncyCastle.Asn1.TeleTrust;
using Org.BouncyCastle.Asn1.X509;
using Org.BouncyCastle.Crypto.Encodings;
using Org.BouncyCastle.Crypto.Engines;
using Org.BouncyCastle.Crypto.Parameters;
using Org.BouncyCastle.Security;
using Org.BouncyCastle.Utilities;
using Org.BouncyCastle.Utilities.Collections;
using System;
using System.Collections.Generic;
namespace Org.BouncyCastle.Crypto.Signers
{
public class RsaDigestSigner : ISigner
{
private readonly IAsymmetricBlockCipher rsaEngine;
private readonly AlgorithmIdentifier algId;
private readonly IDigest digest;
private bool forSigning;
private static readonly IDictionary<string, DerObjectIdentifier> OidMap;
public virtual string AlgorithmName => digest.AlgorithmName + "withRSA";
static RsaDigestSigner()
{
OidMap = new Dictionary<string, DerObjectIdentifier>(StringComparer.OrdinalIgnoreCase);
OidMap["RIPEMD128"] = TeleTrusTObjectIdentifiers.RipeMD128;
OidMap["RIPEMD160"] = TeleTrusTObjectIdentifiers.RipeMD160;
OidMap["RIPEMD256"] = TeleTrusTObjectIdentifiers.RipeMD256;
OidMap["SHA-1"] = X509ObjectIdentifiers.IdSha1;
OidMap["SHA-224"] = NistObjectIdentifiers.IdSha224;
OidMap["SHA-256"] = NistObjectIdentifiers.IdSha256;
OidMap["SHA-384"] = NistObjectIdentifiers.IdSha384;
OidMap["SHA-512"] = NistObjectIdentifiers.IdSha512;
OidMap["SHA-512/224"] = NistObjectIdentifiers.IdSha512_224;
OidMap["SHA-512/256"] = NistObjectIdentifiers.IdSha512_256;
OidMap["SHA3-224"] = NistObjectIdentifiers.IdSha3_224;
OidMap["SHA3-256"] = NistObjectIdentifiers.IdSha3_256;
OidMap["SHA3-384"] = NistObjectIdentifiers.IdSha3_384;
OidMap["SHA3-512"] = NistObjectIdentifiers.IdSha3_512;
OidMap["MD2"] = PkcsObjectIdentifiers.MD2;
OidMap["MD4"] = PkcsObjectIdentifiers.MD4;
OidMap["MD5"] = PkcsObjectIdentifiers.MD5;
}
public RsaDigestSigner(IDigest digest)
: this(digest, CollectionUtilities.GetValueOrNull(OidMap, digest.AlgorithmName))
{
}
public RsaDigestSigner(IDigest digest, DerObjectIdentifier digestOid)
: this(digest, new AlgorithmIdentifier(digestOid, DerNull.Instance))
{
}
public RsaDigestSigner(IDigest digest, AlgorithmIdentifier algId)
: this(new RsaCoreEngine(), digest, algId)
{
}
public RsaDigestSigner(IRsa rsa, IDigest digest, DerObjectIdentifier digestOid)
: this(rsa, digest, new AlgorithmIdentifier(digestOid, DerNull.Instance))
{
}
public RsaDigestSigner(IRsa rsa, IDigest digest, AlgorithmIdentifier algId)
: this(new RsaBlindedEngine(rsa), digest, algId)
{
}
public RsaDigestSigner(IAsymmetricBlockCipher rsaEngine, IDigest digest, AlgorithmIdentifier algId)
{
this.rsaEngine = new Pkcs1Encoding(rsaEngine);
this.digest = digest;
this.algId = algId;
}
public virtual void Init(bool forSigning, ICipherParameters parameters)
{
this.forSigning = forSigning;
ParametersWithRandom parametersWithRandom = parameters as ParametersWithRandom;
AsymmetricKeyParameter asymmetricKeyParameter = (parametersWithRandom == null) ? ((AsymmetricKeyParameter)parameters) : ((AsymmetricKeyParameter)parametersWithRandom.Parameters);
if (forSigning && !asymmetricKeyParameter.IsPrivate)
throw new InvalidKeyException("Signing requires private key.");
if (!forSigning && asymmetricKeyParameter.IsPrivate)
throw new InvalidKeyException("Verification requires public key.");
Reset();
rsaEngine.Init(forSigning, parameters);
}
public virtual void Update(byte input)
{
digest.Update(input);
}
public virtual void BlockUpdate(byte[] input, int inOff, int inLen)
{
digest.BlockUpdate(input, inOff, inLen);
}
public virtual void BlockUpdate(ReadOnlySpan<byte> input)
{
digest.BlockUpdate(input);
}
public virtual int GetMaxSignatureSize()
{
return rsaEngine.GetOutputBlockSize();
}
public virtual byte[] GenerateSignature()
{
if (!forSigning)
throw new InvalidOperationException("RsaDigestSigner not initialised for signature generation.");
byte[] array = new byte[digest.GetDigestSize()];
digest.DoFinal(array, 0);
byte[] array2 = DerEncode(array);
return rsaEngine.ProcessBlock(array2, 0, array2.Length);
}
public virtual bool VerifySignature(byte[] signature)
{
if (forSigning)
throw new InvalidOperationException("RsaDigestSigner not initialised for verification");
byte[] array = new byte[digest.GetDigestSize()];
digest.DoFinal(array, 0);
byte[] array2;
byte[] array3;
try {
array2 = rsaEngine.ProcessBlock(signature, 0, signature.Length);
array3 = DerEncode(array);
} catch (Exception) {
return false;
}
if (array2.Length == array3.Length)
return Arrays.FixedTimeEquals(array2, array3);
if (array2.Length == array3.Length - 2) {
int num = array2.Length - array.Length - 2;
int num2 = array3.Length - array.Length - 2;
array3[1] -= 2;
array3[3] -= 2;
int num3 = 0;
for (int i = 0; i < array.Length; i++) {
num3 |= (array2[num + i] ^ array3[num2 + i]);
}
for (int j = 0; j < num; j++) {
num3 |= (array2[j] ^ array3[j]);
}
return num3 == 0;
}
return false;
}
public virtual void Reset()
{
digest.Reset();
}
private byte[] DerEncode(byte[] hash)
{
if (algId == null)
return hash;
return new DigestInfo(algId, hash).GetDerEncoded();
}
}
}