PoC of introducing SpoofableValue

PoC to check which solution to pick for https://github.com/tokio-rs/axum/issues/2998

axum-extra/src/extract/host.rs

@@ -1,4 +1,7 @@
-use super::rejection::{FailedToResolveHost, HostRejection};
+use super::{
+    rejection::{FailedToResolveHost, HostRejection},
+    SpoofableValue,
+};
 use axum::extract::FromRequestParts;
 use http::{
     header::{HeaderMap, FORWARDED},
@@ -18,7 +21,7 @@ const X_FORWARDED_HOST_HEADER_KEY: &str = "X-Forwarded-Host";
 /// Note that user agents can set `X-Forwarded-Host` and `Host` headers to arbitrary values so make
 /// sure to validate them to avoid security issues.
 #[derive(Debug, Clone)]
-pub struct Host(pub String);
+pub struct Host(pub SpoofableValue);
 
 impl<S> FromRequestParts<S> for Host
 where
@@ -28,7 +31,7 @@ where
 
     async fn from_request_parts(parts: &mut Parts, _state: &S) -> Result<Self, Self::Rejection> {
         if let Some(host) = parse_forwarded(&parts.headers) {
-            return Ok(Host(host.to_owned()));
+            return Ok(Host(SpoofableValue::new(host.to_owned())));
         }
 
         if let Some(host) = parts
@@ -36,7 +39,7 @@ where
             .get(X_FORWARDED_HOST_HEADER_KEY)
             .and_then(|host| host.to_str().ok())
         {
-            return Ok(Host(host.to_owned()));
+            return Ok(Host(SpoofableValue::new(host.to_owned())));
         }
 
         if let Some(host) = parts
@@ -44,11 +47,11 @@ where
             .get(http::header::HOST)
             .and_then(|host| host.to_str().ok())
         {
-            return Ok(Host(host.to_owned()));
+            return Ok(Host(SpoofableValue::new(host.to_owned())));
         }
 
         if let Some(host) = parts.uri.host() {
-            return Ok(Host(host.to_owned()));
+            return Ok(Host(SpoofableValue::new(host.to_owned())));
         }
 
         Err(HostRejection::FailedToResolveHost(FailedToResolveHost))
@@ -81,7 +84,7 @@ mod tests {
 
     fn test_client() -> TestClient {
         async fn host_as_body(Host(host): Host) -> String {
-            host
+            host.spoofable_value()
         }
 
         TestClient::new(Router::new().route("/", get(host_as_body)))

axum-extra/src/extract/mod.rs

@@ -63,3 +63,16 @@ pub use crate::json_lines::JsonLines;
 #[cfg(feature = "typed-header")]
 #[doc(no_inline)]
 pub use crate::typed_header::TypedHeader;
+
+#[derive(Debug, Clone)]
+pub struct SpoofableValue(String);
+
+impl SpoofableValue {
+    pub fn new(value: String) -> Self {
+        Self(value)
+    }
+
+    pub fn spoofable_value(self) -> String {
+        self.0
+    }
+}

axum-extra/src/extract/scheme.rs

@@ -9,6 +9,8 @@ use http::{
     header::{HeaderMap, FORWARDED},
     request::Parts,
 };
+
+use super::SpoofableValue;
 const X_FORWARDED_PROTO_HEADER_KEY: &str = "X-Forwarded-Proto";
 
 /// Extractor that resolves the scheme / protocol of a request.
@@ -21,7 +23,7 @@ const X_FORWARDED_PROTO_HEADER_KEY: &str = "X-Forwarded-Proto";
 /// Note that user agents can set the `X-Forwarded-Proto` header to arbitrary values so make
 /// sure to validate them to avoid security issues.
 #[derive(Debug, Clone)]
-pub struct Scheme(pub String);
+pub struct Scheme(pub SpoofableValue);
 
 /// Rejection type used if the [`Scheme`] extractor is unable to
 /// resolve a scheme.
@@ -43,7 +45,7 @@ where
     async fn from_request_parts(parts: &mut Parts, _state: &S) -> Result<Self, Self::Rejection> {
         // Within Forwarded header
         if let Some(scheme) = parse_forwarded(&parts.headers) {
-            return Ok(Scheme(scheme.to_owned()));
+            return Ok(Scheme(SpoofableValue::new(scheme.to_owned())));
         }
 
         // X-Forwarded-Proto
@@ -52,12 +54,12 @@ where
             .get(X_FORWARDED_PROTO_HEADER_KEY)
             .and_then(|scheme| scheme.to_str().ok())
         {
-            return Ok(Scheme(scheme.to_owned()));
+            return Ok(Scheme(SpoofableValue::new(scheme.to_owned())));
         }
 
         // From parts of an HTTP/2 request
         if let Some(scheme) = parts.uri.scheme_str() {
-            return Ok(Scheme(scheme.to_owned()));
+            return Ok(Scheme(SpoofableValue::new(scheme.to_owned())));
         }
 
         Err(SchemeMissing)
@@ -89,7 +91,7 @@ mod tests {
 
     fn test_client() -> TestClient {
         async fn scheme_as_body(Scheme(scheme): Scheme) -> String {
-            scheme
+            scheme.spoofable_value()
         }
 
         TestClient::new(Router::new().route("/", get(scheme_as_body)))

examples/tls-graceful-shutdown/src/main.rs

@@ -122,7 +122,7 @@ where
     }
 
     let redirect = move |Host(host): Host, uri: Uri| async move {
-        match make_https(host, uri, ports) {
+        match make_https(host.spoofable_value(), uri, ports) {
             Ok(uri) => Ok(Redirect::permanent(&uri.to_string())),
             Err(error) => {
                 tracing::warn!(%error, "failed to convert URI to HTTPS");

examples/tls-rustls/src/main.rs

@@ -88,7 +88,7 @@ async fn redirect_http_to_https(ports: Ports) {
     }
 
     let redirect = move |Host(host): Host, uri: Uri| async move {
-        match make_https(host, uri, ports) {
+        match make_https(host.spoofable_value(), uri, ports) {
             Ok(uri) => Ok(Redirect::permanent(&uri.to_string())),
             Err(error) => {
                 tracing::warn!(%error, "failed to convert URI to HTTPS");