//新加授权程序


using System.Security.Cryptography;

namespace Common
{
    public abstract class AlgHelper
    {
        public static byte[] Decrypt(string publicKey, byte[] data)
        {
            using (RSACryptoServiceProvider cryptoServiceProvider = new RSACryptoServiceProvider())
            {
                cryptoServiceProvider.FromXmlString(publicKey);
                return cryptoServiceProvider.Decrypt(data, false);
            }
        }

        public static void GenerateKey(out string publicKey, out string privateKey)
        {
            using (RSACryptoServiceProvider cryptoServiceProvider = new RSACryptoServiceProvider(1024))
            {
                privateKey = cryptoServiceProvider.ToXmlString(true);
                publicKey = cryptoServiceProvider.ToXmlString(false);
            }
        }

        public static byte[] Encrypt(string privateKey, byte[] data)
        {
            using (RSACryptoServiceProvider cryptoServiceProvider = new RSACryptoServiceProvider())
            {
                cryptoServiceProvider.FromXmlString(privateKey);
                return cryptoServiceProvider.Encrypt(data, false);
            }
        }

        public static byte[] SignatureData(string privateKey, byte[] data)
        {
            using (RSACryptoServiceProvider cryptoServiceProvider = new RSACryptoServiceProvider())
            {
                cryptoServiceProvider.FromXmlString(privateKey);
                RSAPKCS1SignatureFormatter signatureFormatter = new RSAPKCS1SignatureFormatter((AsymmetricAlgorithm)cryptoServiceProvider);
                signatureFormatter.SetHashAlgorithm("SHA1");
                return signatureFormatter.CreateSignature(SHA1.Create().ComputeHash(data));
            }
        }

        public static bool VerifySignature(string publicKey, byte[] rgbSignature, byte[] rgbToBeHash)
        {
            using (RSACryptoServiceProvider cryptoServiceProvider = new RSACryptoServiceProvider())
            {
                cryptoServiceProvider.FromXmlString(publicKey);
                RSAPKCS1SignatureDeformatter signatureDeformatter = new RSAPKCS1SignatureDeformatter((AsymmetricAlgorithm)cryptoServiceProvider);
                signatureDeformatter.SetHashAlgorithm("SHA1");
                return signatureDeformatter.VerifySignature(SHA1.Create().ComputeHash(rgbToBeHash), rgbSignature);
            }
        }
    }
}