From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Sat, 21 Aug 2021 23:16:59 +0000 (+0100)
Subject: introduce MayRoute (loop prevention)
X-Git-Tag: hippotat/1.0.0~122
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ian/git?a=commitdiff_plain;h=c88fd455f807912f4780179a49b2630ca4bdea1b;p=hippotat.git

introduce MayRoute (loop prevention)

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
---

diff --git a/server/server.rs b/server/server.rs
index cfceef6..3093684 100644
--- a/server/server.rs
+++ b/server/server.rs
@@ -38,10 +38,21 @@ pub struct RoutedPacket {
 // not MIME data, valid SLIP (checked)
 pub type RoutedPacketData = Box<[u8]>;
 
+// loop prevention
+mod may_route {
+  #[derive(Clone,Debug)]
+  pub struct MayRoute(());
+  impl MayRoute {
+    pub fn came_from_outside_hippotatd() -> Self { Self(()) }
+  }
+}
+pub use may_route::MayRoute;
+
 #[throws(PacketError)]
 pub async fn route_packet(global: &Global,
                           conn: &str, source: Option<&ClientName>,
-                          packet: RoutedPacketData, daddr: IpAddr)
+                          packet: RoutedPacketData, daddr: IpAddr,
+                          _may_route: MayRoute)
 {
   let c = &global.config;
   let len = packet.len();
diff --git a/server/suser.rs b/server/suser.rs
index dec1a5a..5b7ab0f 100644
--- a/server/suser.rs
+++ b/server/suser.rs
@@ -66,7 +66,7 @@ pub async fn run(global: Arc<Global>,
         let WebRequest {
           initial, initial_remaining, length_hint, mut body,
           boundary_finder,
-          reply_to, conn, mut warnings,
+          reply_to, conn, mut warnings, may_route,
         } = req.ok_or_else(|| anyhow!("webservers all shut down!"))?;
 
         match async {
@@ -142,7 +142,8 @@ pub async fn run(global: Arc<Global>,
               let daddr = ip_packet_addr::<true>(header)?;
               Ok(daddr)
             }, |(daddr,packet)| route_packet(
-              &global, &conn, Some(&ic.link.client), daddr,packet
+              &global, &conn, Some(&ic.link.client), daddr,
+              packet, may_route.clone(),
             ),
               |e| Ok::<_,SlipFramesError<_>>({ warnings.add(&e)?; })
             ).await?;
diff --git a/server/sweb.rs b/server/sweb.rs
index 157261a..d4e825e 100644
--- a/server/sweb.rs
+++ b/server/sweb.rs
@@ -19,6 +19,7 @@ pub struct WebRequest {
   pub reply_to: oneshot::Sender<WebResponse>,
   pub warnings: Warnings,
   pub conn: Arc<String>,
+  pub may_route: MayRoute,
 }
 
 /// Reply from client task to hyper worker pool task
@@ -188,6 +189,7 @@ pub async fn handle(
       warnings: mem::take(&mut warnings),
       reply_to,
       conn: conn.clone(),
+      may_route: MayRoute::came_from_outside_hippotatd(),
     };
 
     client.web.try_send(wreq)