From da7336406d13c75d1257f05cdd9f1769921c621a Mon Sep 17 00:00:00 2001
From: Afshin Arani <afshin@arani.dev>
Date: Sun, 23 Apr 2023 22:34:08 +0330
Subject: [PATCH] Client,Services,Tests: TorClient exit circuit

---
 NOnion.Tests/TorClientTests.cs      |  2 +-
 NOnion/Client/TorClient.fs          | 21 ++++++++++++++++++---
 NOnion/Services/TorServiceClient.fs |  1 +
 NOnion/Services/TorServiceHost.fs   |  5 ++++-
 4 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/NOnion.Tests/TorClientTests.cs b/NOnion.Tests/TorClientTests.cs
index e544a6d8..04cab67a 100644
--- a/NOnion.Tests/TorClientTests.cs
+++ b/NOnion.Tests/TorClientTests.cs
@@ -18,7 +18,7 @@ public class TorClientTests
         private async Task CreateCircuit()
         {
             var client = await TorClient.BootstrapWithEmbeddedListAsync();
-            await client.CreateCircuitAsync(3, FSharpOption<Network.CircuitNodeDetail>.None);
+            await client.CreateCircuitAsync(3, CircuitPurpose.Unknown, FSharpOption<Network.CircuitNodeDetail>.None);
         }
 
         [Test]
diff --git a/NOnion/Client/TorClient.fs b/NOnion/Client/TorClient.fs
index d074efac..851ef3a2 100644
--- a/NOnion/Client/TorClient.fs
+++ b/NOnion/Client/TorClient.fs
@@ -11,6 +11,10 @@ open NOnion.Utility
 open NOnion
 open NOnion.Network
 
+type CircuitPurpose =
+    | Unknown
+    | Exit
+
 type TorClient internal (directory: TorDirectory) =
     static let maximumBootstrapTries = 5
 
@@ -99,6 +103,7 @@ type TorClient internal (directory: TorDirectory) =
 
     member __.CreateCircuit
         (hopsCount: int)
+        (purpose: CircuitPurpose)
         (extendByNodeOpt: Option<CircuitNodeDetail>)
         =
         async {
@@ -145,8 +150,17 @@ type TorClient internal (directory: TorDirectory) =
                                         let rec findUnusedNode() =
                                             async {
                                                 let! _ipEndPoint, nodeDetail =
-                                                    directory.GetRouter
-                                                        RouterType.Normal
+                                                    if numHopsToExtend = 1 then
+                                                        match purpose with
+                                                        | Unknown ->
+                                                            directory.GetRouter
+                                                                RouterType.Normal
+                                                        | Exit ->
+                                                            directory.GetRouter
+                                                                RouterType.Exit
+                                                    else
+                                                        directory.GetRouter
+                                                            RouterType.Normal
 
                                                 if (List.contains
                                                         nodeDetail
@@ -208,9 +222,10 @@ type TorClient internal (directory: TorDirectory) =
     member self.CreateCircuitAsync
         (
             hopsCount: int,
+            purpse: CircuitPurpose,
             extendByNode: Option<CircuitNodeDetail>
         ) =
-        self.CreateCircuit hopsCount extendByNode |> Async.StartAsTask
+        self.CreateCircuit hopsCount purpse extendByNode |> Async.StartAsTask
 
 
     interface IDisposable with
diff --git a/NOnion/Services/TorServiceClient.fs b/NOnion/Services/TorServiceClient.fs
index 22104904..669d5207 100644
--- a/NOnion/Services/TorServiceClient.fs
+++ b/NOnion/Services/TorServiceClient.fs
@@ -76,6 +76,7 @@ type TorServiceClient =
                                         let! circuit =
                                             torClient.CreateCircuit
                                                 2
+                                                CircuitPurpose.Unknown
                                                 (Some hsDirectoryNode)
 
                                         use dirStream = new TorStream(circuit)
diff --git a/NOnion/Services/TorServiceHost.fs b/NOnion/Services/TorServiceHost.fs
index 0c41f558..9e7207fa 100644
--- a/NOnion/Services/TorServiceHost.fs
+++ b/NOnion/Services/TorServiceHost.fs
@@ -383,7 +383,10 @@ type TorServiceHost
                     use torClient = new TorClient(directory)
 
                     let! circuit =
-                        torClient.CreateCircuit 2 (Some hsDirectoryNode)
+                        torClient.CreateCircuit
+                            2
+                            CircuitPurpose.Unknown
+                            (Some hsDirectoryNode)
 
                     use dirStream = new TorStream(circuit)
                     do! dirStream.ConnectToDirectory() |> Async.Ignore