Add option to allow/disallow h1 half closures

The default is set to allow, thus reverting a change made in 3.11.1

Signed-off-by: Thales Fragoso <thales.fragoso@axiros.com>

actix-http/CHANGES.md

@@ -2,7 +2,9 @@
 
 ## Unreleased
 
-- Properly wake Payload receivers when feeding errors or EOF
+- Properly wake Payload receivers when feeding errors or EOF.
+- Add `ServiceConfigBuilder` type to facilitate future configuration extensions.
+- Add a configuration option to allow/disallow half closed connections in HTTP/1. This defaults to allow, reverting the change made in 3.11.1.
 
 ## 3.11.1
 

actix-http/src/builder.rs

@@ -19,6 +19,7 @@ pub struct HttpServiceBuilder<T, S, X = ExpectHandler, U = UpgradeHandler> {
     client_disconnect_timeout: Duration,
     secure: bool,
     local_addr: Option<net::SocketAddr>,
+    h1_allow_half_closed: bool,
     expect: X,
     upgrade: Option<U>,
     on_connect_ext: Option<Rc<ConnectCallback<T>>>,
@@ -40,6 +41,7 @@ where
             client_disconnect_timeout: Duration::ZERO,
             secure: false,
             local_addr: None,
+            h1_allow_half_closed: true,
 
             // dispatcher parts
             expect: ExpectHandler,
@@ -124,6 +126,18 @@ where
         self.client_disconnect_timeout(dur)
     }
 
+    /// Sets whether HTTP/1 connections should support half-closures.
+    ///
+    /// Clients can choose to shutdown their writer-side of the connection after completing their
+    /// request and while waiting for the server response. Setting this to `false` will cause the
+    /// server to abort the connection handling as soon as it detects an EOF from the client.
+    ///
+    /// The default behavior is to allow, i.e. `true`
+    pub fn h1_allow_half_closed(mut self, allow: bool) -> Self {
+        self.h1_allow_half_closed = allow;
+        self
+    }
+
     /// Provide service for `EXPECT: 100-Continue` support.
     ///
     /// Service get called with request that contains `EXPECT` header.
@@ -142,6 +156,7 @@ where
             client_disconnect_timeout: self.client_disconnect_timeout,
             secure: self.secure,
             local_addr: self.local_addr,
+            h1_allow_half_closed: self.h1_allow_half_closed,
             expect: expect.into_factory(),
             upgrade: self.upgrade,
             on_connect_ext: self.on_connect_ext,
@@ -166,6 +181,7 @@ where
             client_disconnect_timeout: self.client_disconnect_timeout,
             secure: self.secure,
             local_addr: self.local_addr,
+            h1_allow_half_closed: self.h1_allow_half_closed,
             expect: self.expect,
             upgrade: Some(upgrade.into_factory()),
             on_connect_ext: self.on_connect_ext,
@@ -201,6 +217,7 @@ where
             .client_disconnect_timeout(self.client_disconnect_timeout)
             .secure(self.secure)
             .local_addr(self.local_addr)
+            .h1_allow_half_closed(self.h1_allow_half_closed)
             .build();
 
         H1Service::with_config(cfg, service.into_factory())
@@ -226,6 +243,7 @@ where
             .client_disconnect_timeout(self.client_disconnect_timeout)
             .secure(self.secure)
             .local_addr(self.local_addr)
+            .h1_allow_half_closed(self.h1_allow_half_closed)
             .build();
 
         crate::h2::H2Service::with_config(cfg, service.into_factory())
@@ -248,6 +266,7 @@ where
             .client_disconnect_timeout(self.client_disconnect_timeout)
             .secure(self.secure)
             .local_addr(self.local_addr)
+            .h1_allow_half_closed(self.h1_allow_half_closed)
             .build();
 
         HttpService::with_config(cfg, service.into_factory())

actix-http/src/config.rs

@@ -23,6 +23,7 @@ impl ServiceConfigBuilder {
     /// - 0 seconds for the client shutdown timeout
     /// - secure value of `false`
     /// - [`None`] for the local address setting
+    /// - Allow for half closed HTTP/1 connections
     pub fn new() -> Self {
         Self::default()
     }
@@ -58,6 +59,16 @@ impl ServiceConfigBuilder {
         self
     }
 
+    /// Sets whether HTTP/1 connections should support half-closures.
+    ///
+    /// Clients can choose to shutdown their writer-side of the connection after completing their
+    /// request and while waiting for the server response. Setting this to `false` will cause the
+    /// server to abort the connection handling as soon as it detects an EOF from the client
+    pub fn h1_allow_half_closed(mut self, allow: bool) -> Self {
+        self.inner.h1_allow_half_closed = allow;
+        self
+    }
+
     /// Builds a [`ServiceConfig`] from this [`ServiceConfigBuilder`] instance
     pub fn build(self) -> ServiceConfig {
         ServiceConfig(Rc::new(self.inner))
@@ -84,6 +95,7 @@ struct Inner {
     secure: bool,
     local_addr: Option<SocketAddr>,
     date_service: DateService,
+    h1_allow_half_closed: bool,
 }
 
 impl Default for Inner {
@@ -95,6 +107,7 @@ impl Default for Inner {
             secure: false,
             local_addr: None,
             date_service: DateService::new(),
+            h1_allow_half_closed: true,
         }
     }
 }
@@ -121,6 +134,7 @@ impl ServiceConfig {
             secure,
             local_addr,
             date_service: DateService::new(),
+            h1_allow_half_closed: true,
         }))
     }
 
@@ -171,6 +185,15 @@ impl ServiceConfig {
         (timeout != Duration::ZERO).then(|| self.now() + timeout)
     }
 
+    /// Whether HTTP/1 connections should support half-closures.
+    ///
+    /// Clients can choose to shutdown their writer-side of the connection after completing their
+    /// request and while waiting for the server response. If this configuration is `false`, the
+    /// server will abort the connection handling as soon as it detects an EOF from the client
+    pub fn h1_allow_half_closed(&self) -> bool {
+        self.0.h1_allow_half_closed
+    }
+
     pub(crate) fn now(&self) -> Instant {
         self.0.date_service.now()
     }

actix-http/src/h1/dispatcher.rs

@@ -1181,8 +1181,16 @@ where
                     let inner_p = inner.as_mut().project();
                     let state_is_none = inner_p.state.is_none();
 
-                    // read half is closed; we do not process any responses
-                    if inner_p.flags.contains(Flags::READ_DISCONNECT) {
+                    // If the read-half is closed, we start the shutdown procedure if either is
+                    // true:
+                    //
+                    // - state is [`State::None`], which means that we're done with request
+                    //   processing, so if the client closed its writer-side it means that it won't
+                    //   send more requests.
+                    // - The user requested to not allow half-closures
+                    if inner_p.flags.contains(Flags::READ_DISCONNECT)
+                        && (!inner_p.config.h1_allow_half_closed() || state_is_none)
+                    {
                         trace!("read half closed; start shutdown");
                         inner_p.flags.insert(Flags::SHUTDOWN);
                     }

actix-web/src/server.rs

@@ -31,6 +31,7 @@ struct Config {
     keep_alive: KeepAlive,
     client_request_timeout: Duration,
     client_disconnect_timeout: Duration,
+    h1_allow_half_closed: bool,
     #[allow(dead_code)] // only dead when no TLS features are enabled
     tls_handshake_timeout: Option<Duration>,
 }
@@ -116,6 +117,7 @@ where
                 keep_alive: KeepAlive::default(),
                 client_request_timeout: Duration::from_secs(5),
                 client_disconnect_timeout: Duration::from_secs(1),
+                h1_allow_half_closed: true,
                 tls_handshake_timeout: None,
             })),
             backlog: 1024,
@@ -257,6 +259,18 @@ where
         self.client_disconnect_timeout(Duration::from_millis(dur))
     }
 
+    /// Sets whether HTTP/1 connections should support half-closures.
+    ///
+    /// Clients can choose to shutdown their writer-side of the connection after completing their
+    /// request and while waiting for the server response. Setting this to `false` will cause the
+    /// server to abort the connection handling as soon as it detects an EOF from the client.
+    ///
+    /// The default behavior is to allow, i.e. `true`
+    pub fn h1_allow_half_closed(self, allow: bool) -> Self {
+        self.config.lock().unwrap().h1_allow_half_closed = allow;
+        self
+    }
+
     /// Sets function that will be called once before each connection is handled.
     ///
     /// It will receive a `&std::any::Any`, which contains underlying connection type and an
@@ -558,6 +572,7 @@ where
                         .keep_alive(cfg.keep_alive)
                         .client_request_timeout(cfg.client_request_timeout)
                         .client_disconnect_timeout(cfg.client_disconnect_timeout)
+                        .h1_allow_half_closed(cfg.h1_allow_half_closed)
                         .local_addr(addr);
 
                     if let Some(handler) = on_connect_fn.clone() {
@@ -602,6 +617,7 @@ where
                         .keep_alive(cfg.keep_alive)
                         .client_request_timeout(cfg.client_request_timeout)
                         .client_disconnect_timeout(cfg.client_disconnect_timeout)
+                        .h1_allow_half_closed(cfg.h1_allow_half_closed)
                         .local_addr(addr);
 
                     if let Some(handler) = on_connect_fn.clone() {
@@ -677,6 +693,7 @@ where
                     let svc = HttpService::build()
                         .keep_alive(c.keep_alive)
                         .client_request_timeout(c.client_request_timeout)
+                        .h1_allow_half_closed(c.h1_allow_half_closed)
                         .client_disconnect_timeout(c.client_disconnect_timeout);
 
                     let svc = if let Some(handler) = on_connect_fn.clone() {
@@ -728,6 +745,7 @@ where
                     let svc = HttpService::build()
                         .keep_alive(c.keep_alive)
                         .client_request_timeout(c.client_request_timeout)
+                        .h1_allow_half_closed(c.h1_allow_half_closed)
                         .client_disconnect_timeout(c.client_disconnect_timeout);
 
                     let svc = if let Some(handler) = on_connect_fn.clone() {
@@ -794,6 +812,7 @@ where
                     let svc = HttpService::build()
                         .keep_alive(c.keep_alive)
                         .client_request_timeout(c.client_request_timeout)
+                        .h1_allow_half_closed(c.h1_allow_half_closed)
                         .client_disconnect_timeout(c.client_disconnect_timeout);
 
                     let svc = if let Some(handler) = on_connect_fn.clone() {
@@ -860,6 +879,7 @@ where
                     let svc = HttpService::build()
                         .keep_alive(c.keep_alive)
                         .client_request_timeout(c.client_request_timeout)
+                        .h1_allow_half_closed(c.h1_allow_half_closed)
                         .client_disconnect_timeout(c.client_disconnect_timeout);
 
                     let svc = if let Some(handler) = on_connect_fn.clone() {
@@ -927,6 +947,7 @@ where
                         .keep_alive(c.keep_alive)
                         .client_request_timeout(c.client_request_timeout)
                         .client_disconnect_timeout(c.client_disconnect_timeout)
+                        .h1_allow_half_closed(c.h1_allow_half_closed)
                         .local_addr(addr);
 
                     let svc = if let Some(handler) = on_connect_fn.clone() {
@@ -995,6 +1016,7 @@ where
                         .keep_alive(c.keep_alive)
                         .client_request_timeout(c.client_request_timeout)
                         .client_disconnect_timeout(c.client_disconnect_timeout)
+                        .h1_allow_half_closed(c.h1_allow_half_closed)
                         .finish(map_config(fac, move |_| config.clone())),
                 )
             },
@@ -1036,6 +1058,7 @@ where
                 let mut svc = HttpService::build()
                     .keep_alive(c.keep_alive)
                     .client_request_timeout(c.client_request_timeout)
+                    .h1_allow_half_closed(c.h1_allow_half_closed)
                     .client_disconnect_timeout(c.client_disconnect_timeout);
 
                 if let Some(handler) = on_connect_fn.clone() {