MARKUS

using NetSparkleUpdater.AppCastGenerator;

using Org.BouncyCastle.Crypto;

using Org.BouncyCastle.Crypto.Generators;

using Org.BouncyCastle.Crypto.Parameters;

using Org.BouncyCastle.Security;

using System;

using System.IO;

using System.Linq;

using Xunit;

namespace NetSparkle.Tests.AppCastGenerator

{

    public class SignatureManagerTests

    {

        private SignatureManager GetSignatureManager()

        {

            var manager = new SignatureManager();

            // make sure we don't overwrite user's NetSparkle keys!!

            manager.SetStorageDirectory(Path.Combine(Path.GetTempPath(), "netsparkle-tests"));

            return manager;

        }

        [Fact]

        public void TestKeysExist()

        {

            var manager = GetSignatureManager();

            manager.Generate(true);

            Assert.True(manager.KeysExist());

        }

        [Fact]

        public void CanGenerateKeys()

        {

            var manager = GetSignatureManager();

            manager.Generate(true);

            var publicKey = manager.GetPublicKey();

            Assert.NotNull(publicKey);

            Assert.NotEmpty(publicKey);

            var privateKey = manager.GetPrivateKey();

            Assert.NotNull(privateKey);

            Assert.NotEmpty(privateKey);

        }

        // https://stackoverflow.com/a/1344242/3938401

        private static string RandomString(int length)

        {

            Random random = new SecureRandom();

            const string chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";

            return new string(Enumerable.Repeat(chars, length)

              .Select(s => s[random.Next(s.Length)]).ToArray());

        }

        [Fact]

        public void CanGetAndVerifySignature()

        {

            // create tmp file 

            var tempData = RandomString(1024);

            var path = Path.GetTempFileName();

            File.WriteAllText(path, tempData);

            Assert.True(File.Exists(path));

            Assert.Equal(tempData, File.ReadAllText(path));

            // get signature of file

            var manager = GetSignatureManager();

            manager.Generate(true);

            var signature = manager.GetSignatureForFile(path);

            // verify signature

            Assert.True(manager.VerifySignature(path, signature));

            // get rid of temp file

            File.Delete(path);

        }

        [Fact]

        public void CanGetAndVerifySignatureFromEnvironment()

        {

            // create tmp file 

            var tempData = RandomString(1024);

            var path = Path.GetTempFileName();

            File.WriteAllText(path, tempData);

            Assert.True(File.Exists(path));

            Assert.Equal(tempData, File.ReadAllText(path));

            // create keys

            var Random = new SecureRandom();

            Ed25519KeyPairGenerator kpg = new Ed25519KeyPairGenerator();

            kpg.Init(new Ed25519KeyGenerationParameters(Random));

            AsymmetricCipherKeyPair kp = kpg.GenerateKeyPair();

            Ed25519PrivateKeyParameters privateKey = (Ed25519PrivateKeyParameters)kp.Private;

            Ed25519PublicKeyParameters publicKey = (Ed25519PublicKeyParameters)kp.Public;

            var privKeyBase64 = Convert.ToBase64String(privateKey.GetEncoded());

            var pubKeyBase64 = Convert.ToBase64String(publicKey.GetEncoded());

            var manager = GetSignatureManager();

            Environment.SetEnvironmentVariable(SignatureManager.PrivateKeyEnvironmentVariable, privKeyBase64);

            Environment.SetEnvironmentVariable(SignatureManager.PublicKeyEnvironmentVariable, pubKeyBase64);

            // get signature of file

            var signature = manager.GetSignatureForFile(path);

            manager.Generate(true); // force regeneration of keys to "prove" that we are using environment

            // verify signature

            Assert.True(manager.VerifySignature(path, signature));

            // get rid of temp file

            File.Delete(path);

        }

    }

}