Client,Network,Services: add TorClient

This commit aims to introduce a simple API for end users.

Working with network especially Tor routers is flaky and
delegating retry logic implementation to users causes NOnion to
be unreliable in CI and in normal use, this commit introduces
retry logic in some places where it's needed the most. This
should hopefully make NOnion more reliable.

NOnion.Tests/HiddenServicesTests.cs

@@ -16,6 +16,7 @@
 using NOnion.Network;
 using NOnion.Http;
 using NOnion.Cells.Relay;
+using NOnion.Client;
 using NOnion.Directory;
 using NOnion.Tests.Utility;
 using NOnion.Services;
@@ -24,6 +25,23 @@ namespace NOnion.Tests
 {
     public class HiddenServicesTests
     {
+        [OneTimeSetUp]
+        public void Init()
+        {
+            cachePath =
+                new DirectoryInfo(
+                    Path.Combine(
+                        Path.GetTempPath(),
+                        Path.GetFileNameWithoutExtension(
+                            Path.GetRandomFileName()
+                        )
+                    )
+                );
+            cachePath.Create();
+        }
+
+        private DirectoryInfo cachePath = null;
+
         /* It's possible that the router returned by GetRandomFallbackDirectory or
          * GetRandomRoutersForDirectoryBrowsing be inaccessable so we need to continue
          * retrying if an exceptions happened to make sure the issues are not related
@@ -33,11 +51,8 @@ public class HiddenServicesTests
 
         private async Task CreateIntroductionCircuit()
         {
-            var node = (CircuitNodeDetail.Create)(await CircuitHelper.GetRandomRoutersForDirectoryBrowsingWithRetry()).First();
-            using TorGuard guard = await TorGuard.NewClientAsync(node.EndPoint);
-            var circuit = new TorCircuit(guard);
-
-            await circuit.CreateAsync(CircuitNodeDetail.FastCreate);
+            using TorClient torClient = await TorClient.BootstrapWithGithubAsync(cachePath);
+            var circuit = await torClient.CreateCircuitAsync(1, CircuitPurpose.Unknown, FSharpOption<CircuitNodeDetail>.None);
             await circuit.RegisterAsIntroductionPointAsync(FSharpOption<AsymmetricCipherKeyPair>.None, StubCallback, DisconnectionCallback);
         }
 
@@ -61,12 +76,8 @@ private async Task CreateRendezvousCircuit()
             var array = new byte[Constants.RendezvousCookieLength];
             RandomNumberGenerator.Create().GetNonZeroBytes(array);
 
-            var nodes = await CircuitHelper.GetRandomRoutersForDirectoryBrowsingWithRetry(2);
-            using TorGuard guard = await TorGuard.NewClientAsync(((CircuitNodeDetail.Create)nodes[0]).EndPoint);
-            var circuit = new TorCircuit(guard);
-
-            await circuit.CreateAsync(nodes[0]);
-            await circuit.ExtendAsync(nodes[1]);
+            using TorClient torClient = await TorClient.BootstrapWithGithubAsync(cachePath);
+            var circuit = await torClient.CreateCircuitAsync(2, CircuitPurpose.Unknown, FSharpOption<CircuitNodeDetail>.None);
             await circuit.RegisterAsRendezvousPointAsync(array);
         }
 
@@ -92,10 +103,10 @@ private async Task<int> ReadExact(TorStream stream, byte[] buffer, int off, int
 
         public async Task BrowseFacebookOverHS()
         {
-            TorDirectory directory = await TorDirectory.BootstrapAsync(FallbackDirectorySelector.GetRandomFallbackDirectory(), new DirectoryInfo(Path.GetTempPath()));
+            using TorClient torClient = await TorClient.BootstrapWithGithubAsync(cachePath);
 
-            var client = await TorServiceClient.ConnectAsync(directory, "facebookwkhpilnemxj7asaniu7vnjjbiltxjqhye3mhbshg7kx5tfyd.onion");
-            var httpClient = new TorHttpClient(client.GetStream(), "facebookwkhpilnemxj7asaniu7vnjjbiltxjqhye3mhbshg7kx5tfyd.onion");
+            var serviceClient = await TorServiceClient.ConnectAsync(torClient, "facebookwkhpilnemxj7asaniu7vnjjbiltxjqhye3mhbshg7kx5tfyd.onion");
+            var httpClient = new TorHttpClient(serviceClient.GetStream(), "facebookwkhpilnemxj7asaniu7vnjjbiltxjqhye3mhbshg7kx5tfyd.onion");
 
             try
             {
@@ -117,11 +128,11 @@ public void CanBrowseFacebookOverHS()
 
         public async Task BrowseFacebookOverHSWithTLS()
         {
-            TorDirectory directory = await TorDirectory.BootstrapAsync(FallbackDirectorySelector.GetRandomFallbackDirectory(), new DirectoryInfo(Path.GetTempPath()));
-
-            var client = await TorServiceClient.ConnectAsync(directory, "facebookwkhpilnemxj7asaniu7vnjjbiltxjqhye3mhbshg7kx5tfyd.onion:443");
+            using TorClient torClient = await TorClient.BootstrapWithGithubAsync(cachePath);
+            
+            var serviceClient = await TorServiceClient.ConnectAsync(torClient, "facebookwkhpilnemxj7asaniu7vnjjbiltxjqhye3mhbshg7kx5tfyd.onion:443");
 
-            var sslStream = new SslStream(client.GetStream(), true, (sender, cert, chain, sslPolicyErrors) => true);
+            var sslStream = new SslStream(serviceClient.GetStream(), true, (sender, cert, chain, sslPolicyErrors) => true);
             await sslStream.AuthenticateAsClientAsync(string.Empty, null, SslProtocols.Tls12, false);
 
             var httpClientOverSslStream = new TorHttpClient(sslStream, "www.facebookwkhpilnemxj7asaniu7vnjjbiltxjqhye3mhbshg7kx5tfyd.onion");
@@ -147,18 +158,16 @@ public void CanBrowseFacebookOverHSWithTLS()
 
         public async Task EstablishAndCommunicateOverHSConnectionOnionStyle()
         {
-            int descriptorUploadRetryLimit = 2;
-
-            TorDirectory directory = await TorDirectory.BootstrapAsync(FallbackDirectorySelector.GetRandomFallbackDirectory(), new DirectoryInfo(Path.GetTempPath()));
-
+            using TorClient torClient = await TorClient.BootstrapWithGithubAsync(cachePath);
+
             TorLogger.Log("Finished bootstraping");
 
             SecureRandom random = new SecureRandom();
             Ed25519KeyPairGenerator kpGen = new Ed25519KeyPairGenerator();
             kpGen.Init(new Ed25519KeyGenerationParameters(random));
             Ed25519PrivateKeyParameters masterPrivateKey = (Ed25519PrivateKeyParameters)kpGen.GenerateKeyPair().Private;
 
-            TorServiceHost host = new TorServiceHost(directory, descriptorUploadRetryLimit, TestsRetryCount, FSharpOption<Ed25519PrivateKeyParameters>.Some(masterPrivateKey));
+            TorServiceHost host = new TorServiceHost(torClient, FSharpOption<Ed25519PrivateKeyParameters>.Some(masterPrivateKey));
             await host.StartAsync();
 
             TorLogger.Log("Finished starting HS host");
@@ -175,8 +184,8 @@ public async Task EstablishAndCommunicateOverHSConnectionOnionStyle()
 
             var clientSide =
                 Task.Run(async () => {
-                    var client = await TorServiceClient.ConnectAsync(directory, host.ExportUrl());
-                    var stream = client.GetStream();
+                    var serviceClient = await TorServiceClient.ConnectAsync(torClient, host.ExportUrl());
+                    var stream = serviceClient.GetStream();
                     var lengthBytes = new byte[sizeof(int)];
                     await ReadExact(stream, lengthBytes, 0, lengthBytes.Length);
                     var length = BitConverter.ToInt32(lengthBytes);

NOnion.Tests/TorClientTests.cs

@@ -0,0 +1,47 @@
+using Microsoft.FSharp.Core;
+using System.IO;
+using System.Threading.Tasks;
+
+using NUnit.Framework;
+
+using NOnion.Client;
+
+namespace NOnion.Tests
+{
+    public class TorClientTests
+    {
+        private async Task BootstrapWithGithub()
+        {
+            await TorClient.BootstrapWithGithubAsync(FSharpOption<DirectoryInfo>.None);
+        }
+
+        [Test]
+        public void CanBootstrapWithGithub()
+        {
+            Assert.DoesNotThrowAsync(BootstrapWithGithub);
+        }
+
+        private async Task BootstrapWithEmbeddedList()
+        {
+            await TorClient.BootstrapWithEmbeddedListAsync(FSharpOption<DirectoryInfo>.None);
+        }
+
+        [Test]
+        public void CanBootstrapWithEmbeddedList()
+        {
+            Assert.DoesNotThrowAsync(BootstrapWithEmbeddedList);
+        }
+
+        private async Task CreateCircuit()
+        {
+            using TorClient client = await TorClient.BootstrapWithEmbeddedListAsync(FSharpOption<DirectoryInfo>.None);
+            await client.CreateCircuitAsync(3, CircuitPurpose.Unknown, FSharpOption<Network.CircuitNodeDetail>.None);
+        }
+
+        [Test]
+        public void CanCreateCircuit()
+        {
+            Assert.DoesNotThrowAsync(CreateCircuit);
+        }
+    }
+}