C# HashAlgorithm.ToString方法代码示例

		//private bool VerifySignature (ASN1 cs, byte[] calculatedMessageDigest, string hashName) 
		private bool VerifySignature (PKCS7.SignedData sd, byte[] calculatedMessageDigest, HashAlgorithm ha) 
		{
			string contentType = null;
			ASN1 messageDigest = null;
//			string spcStatementType = null;
//			string spcSpOpusInfo = null;

			for (int i=0; i < sd.SignerInfo.AuthenticatedAttributes.Count; i++) {
				ASN1 attr = (ASN1) sd.SignerInfo.AuthenticatedAttributes [i];
				string oid = ASN1Convert.ToOid (attr[0]);
				switch (oid) {
					case "1.2.840.113549.1.9.3":
						// contentType
						contentType = ASN1Convert.ToOid (attr[1][0]);
						break;
					case "1.2.840.113549.1.9.4":
						// messageDigest
						messageDigest = attr[1][0];
						break;
					case "1.3.6.1.4.1.311.2.1.11":
						// spcStatementType (Microsoft code signing)
						// possible values
						// - individualCodeSigning (1 3 6 1 4 1 311 2 1 21)
						// - commercialCodeSigning (1 3 6 1 4 1 311 2 1 22)
//						spcStatementType = ASN1Convert.ToOid (attr[1][0][0]);
						break;
					case "1.3.6.1.4.1.311.2.1.12":
						// spcSpOpusInfo (Microsoft code signing)
/*						try {
							spcSpOpusInfo = System.Text.Encoding.UTF8.GetString (attr[1][0][0][0].Value);
						}
						catch (NullReferenceException) {
							spcSpOpusInfo = null;
						}*/
						break;
					default:
						break;
				}
			}
			if (contentType != spcIndirectDataContext)
				return false;

			// verify message digest
			if (messageDigest == null)
				return false;
			if (!messageDigest.CompareValue (calculatedMessageDigest))
				return false;

			// verify signature
			string hashOID = CryptoConfig.MapNameToOID (ha.ToString ());
			
			// change to SET OF (not [0]) as per PKCS #7 1.5
			ASN1 aa = new ASN1 (0x31);
			foreach (ASN1 a in sd.SignerInfo.AuthenticatedAttributes)
				aa.Add (a);
			ha.Initialize ();
			byte[] p7hash = ha.ComputeHash (aa.GetBytes ());

			byte[] signature = sd.SignerInfo.Signature;
			// we need to find the specified certificate
			string issuer = sd.SignerInfo.IssuerName;
			byte[] serial = sd.SignerInfo.SerialNumber;
			foreach (X509Certificate x509 in coll) {
				if (CompareIssuerSerial (issuer, serial, x509)) {
					// don't verify is key size don't match
					if (x509.PublicKey.Length > (signature.Length >> 3)) {
						// return the signing certificate even if the signature isn't correct
						// (required behaviour for 2.0 support)
						signingCertificate = x509;
						RSACryptoServiceProvider rsa = (RSACryptoServiceProvider) x509.RSA;
						if (rsa.VerifyHash (p7hash, hashOID, signature)) {
							signerChain.LoadCertificates (coll);
							trustedRoot = signerChain.Build (x509);
							break; 
						}
					}
				}
			}

			// timestamp signature is optional
			if (sd.SignerInfo.UnauthenticatedAttributes.Count == 0) {
				trustedTimestampRoot = true;
			}  else {
				for (int i = 0; i < sd.SignerInfo.UnauthenticatedAttributes.Count; i++) {
					ASN1 attr = (ASN1) sd.SignerInfo.UnauthenticatedAttributes[i];
					string oid = ASN1Convert.ToOid (attr[0]);
					switch (oid) {
					case PKCS7.Oid.countersignature:
						// SEQUENCE {
						//   OBJECT IDENTIFIER
						//     countersignature (1 2 840 113549 1 9 6)
						//   SET {
						PKCS7.SignerInfo cs = new PKCS7.SignerInfo (attr[1]);
						trustedTimestampRoot = VerifyCounterSignature (cs, signature);
						break;
					default:
						// we don't support other unauthenticated attributes
						break;
					}
//.........这里部分代码省略.........

		public virtual void Create () 
		{
			// Note: These tests will only be valid without a "machine.config" file
			// or a "machine.config" file that do not modify the default algorithm
			// configuration.
// FIXME: Change namespace when (or if) classes are moved into corlib
			const string defaultSHA224 = "Mono.Security.Cryptography.SHA224Managed";

			// try to build the default implementation
			SHA224 hash = SHA224.Create ();
			Assert.AreEqual (hash.ToString (), defaultSHA224, "SHA224.Create()");

			// try to build, in every way, a SHA224 implementation
			hash = SHA224.Create ("SHA224");
			Assert.AreEqual (hash.ToString (), defaultSHA224, "SHA224.Create('SHA224')");
			hash = SHA224.Create ("SHA-224");
			Assert.AreEqual (hash.ToString (), defaultSHA224, "SHA224.Create('SHA-224')");
		}

		// PKCS #1 v.2.1, Section 9.2
		// EMSA-PKCS1-v1_5-Encode
		public static byte[] Encode_v15 (HashAlgorithm hash, byte[] hashValue, int emLength) 
		{
			if (hashValue.Length != (hash.HashSize >> 3))
				throw new CryptographicException ("bad hash length for " + hash.ToString ());

			// DigestInfo ::= SEQUENCE {
			//	digestAlgorithm AlgorithmIdentifier,
			//	digest OCTET STRING
			// }
		
			byte[] t = null;

			string oid = CryptoConfig.MapNameToOID (hash.ToString ());
			if (oid != null)
			{
				ASN1 digestAlgorithm = new ASN1 (0x30);
				digestAlgorithm.Add (new ASN1 (CryptoConfig.EncodeOID (oid)));
				digestAlgorithm.Add (new ASN1 (0x05));		// NULL
				ASN1 digest = new ASN1 (0x04, hashValue);
				ASN1 digestInfo = new ASN1 (0x30);
				digestInfo.Add (digestAlgorithm);
				digestInfo.Add (digest);

				t = digestInfo.GetBytes ();
			}
			else
			{
				// There are no valid OID, in this case t = hashValue
				// This is the case of the MD5SHA hash algorithm
				t = hashValue;
			}

			Buffer.BlockCopy (hashValue, 0, t, t.Length - hashValue.Length, hashValue.Length);
	
			int PSLength = System.Math.Max (8, emLength - t.Length - 3);
			// PS = PSLength of 0xff
	
			// EM = 0x00 | 0x01 | PS | 0x00 | T
			byte[] EM = new byte [PSLength + t.Length + 3];
			EM [1] = 0x01;
			for (int i=2; i < PSLength + 2; i++)
				EM[i] = 0xff;
			Buffer.BlockCopy (t, 0, EM, PSLength + 3, t.Length);
	
			return EM;
		}

 protected byte GetHashAlgorithmCode(HashAlgorithm value)
 {
     switch (value)
     {
         case HashAlgorithm.Crc32:
             return Crc32HashAlgorithm;
         case HashAlgorithm.MD5:
             return MD5HashAlgorithm;
         case HashAlgorithm.Sha1:
             return Sha1HashAlgorithm;
         case HashAlgorithm.TwosComplement:
             return TwosComplementHashAlgorithm;
         case HashAlgorithm.Xor:
             return XorHashAlgorithm;
         default:
             throw new ArgumentOutOfRangeException("Value not recognized as a valid constant (value = " + value.ToString() + ").");
     }
 }