feat: do not use host header on http2 for guard (#3525)

* feat(guard): do not use host header on http2 for guard

* docs: update changelog

---------

Co-authored-by: Rob Ede <robjtede@icloud.com>

Author: joelwurtz

actix-web/CHANGES.md

@@ -6,6 +6,7 @@
 - Improve handling of non-UTF-8 header values in `Logger` middleware.
 - Add `HttpServer::shutdown_signal()` method.
 - Mark `HttpServer` as `#[must_use]`.
+- Ignore `Host` header in `Host` guard when connection protocol is HTTP/2.
 - Re-export `mime` dependency.
 - Update `brotli` dependency to `8`.
 

actix-web/src/guard/host.rs

@@ -1,4 +1,4 @@
-use actix_http::{header, uri::Uri, RequestHead};
+use actix_http::{header, uri::Uri, RequestHead, Version};
 
 use super::{Guard, GuardContext};
 
@@ -66,6 +66,7 @@ fn get_host_uri(req: &RequestHead) -> Option<Uri> {
     req.headers
         .get(header::HOST)
         .and_then(|host_value| host_value.to_str().ok())
+        .filter(|_| req.version < Version::HTTP_2)
         .or_else(|| req.uri.host())
         .and_then(|host| host.parse().ok())
 }
@@ -123,6 +124,38 @@ mod tests {
     use super::*;
     use crate::test::TestRequest;
 
+    #[test]
+    fn host_not_from_header_if_http2() {
+        let req = TestRequest::default()
+            .uri("www.rust-lang.org")
+            .insert_header((
+                header::HOST,
+                header::HeaderValue::from_static("www.example.com"),
+            ))
+            .to_srv_request();
+
+        let host = Host("www.example.com");
+        assert!(host.check(&req.guard_ctx()));
+
+        let host = Host("www.rust-lang.org");
+        assert!(!host.check(&req.guard_ctx()));
+
+        let req = TestRequest::default()
+            .version(actix_http::Version::HTTP_2)
+            .uri("www.rust-lang.org")
+            .insert_header((
+                header::HOST,
+                header::HeaderValue::from_static("www.example.com"),
+            ))
+            .to_srv_request();
+
+        let host = Host("www.example.com");
+        assert!(!host.check(&req.guard_ctx()));
+
+        let host = Host("www.rust-lang.org");
+        assert!(host.check(&req.guard_ctx()));
+    }
+
     #[test]
     fn host_from_header() {
         let req = TestRequest::default()