add support for rfc7239 forwarded

Cargo.lock

@@ -827,6 +827,15 @@ dependencies = [
  "winapi 0.3.9",
 ]
 
+[[package]]
+name = "rfc7239"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "087317b3cf7eb481f13bd9025d729324b7cd068d6f470e2d76d049e191f5ba47"
+dependencies = [
+ "uncased",
+]
+
 [[package]]
 name = "ryu"
 version = "1.0.5"
@@ -1101,6 +1110,15 @@ version = "1.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "373c8a200f9e67a0c95e62a4f52fbf80c23b4381c05a17845531982fa99e6b33"
 
+[[package]]
+name = "uncased"
+version = "0.9.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "369fa7fd7969c5373541d3c9a40dc1b76ce676fc87aba30d87c0ad3b97fad179"
+dependencies = [
+ "version_check",
+]
+
 [[package]]
 name = "unicase"
 version = "2.6.0"
@@ -1204,8 +1222,9 @@ dependencies = [
 
 [[package]]
 name = "warp-real-ip"
-version = "0.1.0"
+version = "0.1.1"
 dependencies = [
+ "rfc7239",
  "tokio",
  "warp",
 ]

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "warp-real-ip"
 description = "Warp filter to get the \"real ip\" of the remote client"
-version = "0.1.0"
+version = "0.1.1"
 authors = ["Robin Appelman <robin@icewind.nl>"]
 edition = "2018"
 keywords = ["warp"]
@@ -12,6 +12,7 @@ documentation = "https://docs.rs/warp-real-ip"
 
 [dependencies]
 warp = { version = "0.2" }
+rfc7239 = "0.1"
 
 [dev-dependencies]
 tokio = { version = "0.2", features = ["macros"] }

src/lib.rs

@@ -1,3 +1,4 @@
+use rfc7239::{parse, Forwarded, NodeIdentifier, NodeName};
 use std::convert::Infallible;
 use std::iter::once;
 use std::net::{IpAddr, SocketAddr};
@@ -48,25 +49,47 @@ pub fn real_ip(
 /// Creates a `Filter` that extracts the ip addresses from the the "forwarded for" chain
 pub fn get_forwarded_for() -> impl Filter<Extract = (Vec<IpAddr>,), Error = Infallible> + Clone {
     warp::header("x-forwarded-for")
-        .map(|list: IpList| list.0)
+        .map(|list: CommaSeparated<IpAddr>| list.into_inner())
         .or(warp::header("x-real-ip").map(|ip| vec![ip]))
         .unify()
+        .or(warp::header("forwarded").map(|header: String| {
+            parse(&header)
+                .filter_map(|forward| match forward {
+                    Ok(Forwarded {
+                        forwarded_for:
+                            Some(NodeIdentifier {
+                                name: NodeName::Ip(ip),
+                                ..
+                            }),
+                        ..
+                    }) => Some(ip),
+                    _ => None,
+                })
+                .collect::<Vec<_>>()
+        }))
+        .unify()
         .or(warp::any().map(|| vec![]))
         .unify()
 }
 
 /// Newtype so we can implement FromStr
-struct IpList(Vec<IpAddr>);
+struct CommaSeparated<T>(Vec<T>);
 
-impl FromStr for IpList {
-    type Err = <IpAddr as FromStr>::Err;
+impl<T> CommaSeparated<T> {
+    pub fn into_inner(self) -> Vec<T> {
+        self.0
+    }
+}
+
+impl<T: FromStr> FromStr for CommaSeparated<T> {
+    type Err = T::Err;
 
     fn from_str(s: &str) -> Result<Self, Self::Err> {
         let vec = s
             .split(',')
             .map(str::trim)
-            .map(IpAddr::from_str)
+            .map(T::from_str)
             .collect::<Result<Vec<_>, _>>()?;
-        Ok(IpList(vec))
+        Ok(CommaSeparated(vec))
     }
 }

tests/tests.rs

@@ -61,3 +61,25 @@ async fn test_nested_allowed() {
         .await;
     assert_eq!(res.body(), "11.11.11.11");
 }
+
+#[tokio::test]
+async fn test_trusted_forwarded() {
+    let remote: IpAddr = [1, 2, 3, 4].into();
+    let res = warp::test::request()
+        .remote_addr((remote, 80).into())
+        .header("forwarded", "for=10.10.10.10")
+        .reply(&serve(vec![remote]))
+        .await;
+    assert_eq!(res.body(), "10.10.10.10");
+}
+
+#[tokio::test]
+async fn test_trusted_forwarded_no_for() {
+    let remote: IpAddr = [1, 2, 3, 4].into();
+    let res = warp::test::request()
+        .remote_addr((remote, 80).into())
+        .header("forwarded", "by=11.11.11.11")
+        .reply(&serve(vec![remote]))
+        .await;
+    assert_eq!(res.body(), "1.2.3.4");
+}