Compression

5 files changed, 384 insertions, 69 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 9f5b314..a094835 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3,6 +3,16 @@
 version = 3
 
 [[package]]
+name = "accept-encoding-fork"
+version = "0.2.0-alpha.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "104af0beedb34a7590b5cd62c3965e89a405dfc4ac88f9704ebbeaf8b0db4597"
+dependencies = [
+ "failure",
+ "http 0.2.5",
+]
+
+[[package]]
 name = "acme-micro"
 version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -20,6 +30,21 @@ dependencies = [
 ]
 
 [[package]]
+name = "addr2line"
+version = "0.17.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b9ecd88a8c8378ca913a680cd98f0f13ac67383d35993f86c90a70e3f137816b"
+dependencies = [
+ "gimli",
+]
+
+[[package]]
+name = "adler"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f26201604c87b1e01bd3d98f8d5d9a8fcbb815e8cedb41ffccbeb4bf593a35fe"
+
+[[package]]
 name = "aho-corasick"
 version = "0.7.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -29,6 +54,21 @@ dependencies = [
 ]
 
 [[package]]
+name = "alloc-no-stdlib"
+version = "2.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "35ef4730490ad1c4eae5c4325b2a95f521d023e5c885853ff7aca0a6a1631db3"
+
+[[package]]
+name = "alloc-stdlib"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "697ed7edc0f1711de49ce108c541623a0af97c6c60b2f6e2b65229847ac843c2"
+dependencies = [
+ "alloc-no-stdlib",
+]
+
+[[package]]
 name = "ansi_term"
 version = "0.12.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -44,6 +84,22 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8b26702f315f53b6071259e15dd9d64528213b44d61de1ec926eca7715d62203"
 
 [[package]]
+name = "async-compression"
+version = "0.3.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5443ccbb270374a2b1055fc72da40e1f237809cd6bb0e97e66d264cd138473a6"
+dependencies = [
+ "brotli",
+ "flate2",
+ "futures-core",
+ "memchr",
+ "pin-project-lite",
+ "tokio 1.14.0",
+ "zstd",
+ "zstd-safe",
+]
+
+[[package]]
 name = "atty"
 version = "0.2.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -61,6 +117,21 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "cdb031dd78e28731d87d56cc8ffef4a8f36ca26c38fe2de700543e627f8a464a"
 
 [[package]]
+name = "backtrace"
+version = "0.3.63"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "321629d8ba6513061f26707241fa9bc89524ff1cd7a915a97ef0c62c666ce1b6"
+dependencies = [
+ "addr2line",
+ "cc",
+ "cfg-if 1.0.0",
+ "libc",
+ "miniz_oxide",
+ "object",
+ "rustc-demangle",
+]
+
+[[package]]
 name = "base-x"
 version = "0.2.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -79,6 +150,27 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
 
 [[package]]
+name = "brotli"
+version = "3.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "71cb90ade945043d3d53597b2fc359bb063db8ade2bcffe7997351d0756e9d50"
+dependencies = [
+ "alloc-no-stdlib",
+ "alloc-stdlib",
+ "brotli-decompressor",
+]
+
+[[package]]
+name = "brotli-decompressor"
+version = "2.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "59ad2d4653bf5ca36ae797b1f4bb4dbddb60ce49ca4aed8a2ce4829f60425b80"
+dependencies = [
+ "alloc-no-stdlib",
+ "alloc-stdlib",
+]
+
+[[package]]
 name = "bumpalo"
 version = "3.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -112,6 +204,9 @@ name = "cc"
 version = "1.0.72"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "22a9137b95ea06864e018375b72adfb7db6e6f68cfc8df5a04d00288050485ee"
+dependencies = [
+ "jobserver",
+]
 
 [[package]]
 name = "cfg-if"
@@ -219,6 +314,15 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5827cebf4670468b8772dd191856768aedcb1b0278a04f989f7766351917b9dc"
 
 [[package]]
+name = "crc32fast"
+version = "1.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "738c290dfaea84fc1ca15ad9c168d083b05a714e1efddd8edaab678dc28d2836"
+dependencies = [
+ "cfg-if 1.0.0",
+]
+
+[[package]]
 name = "crossbeam-deque"
 version = "0.7.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -310,6 +414,40 @@ dependencies = [
 ]
 
 [[package]]
+name = "failure"
+version = "0.1.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d32e9bd16cc02eae7db7ef620b392808b89f6a5e16bb3497d159c6b92a0f4f86"
+dependencies = [
+ "backtrace",
+ "failure_derive",
+]
+
+[[package]]
+name = "failure_derive"
+version = "0.1.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "aa4da3c766cd7a0db8242e326e9e4e081edd567072893ed320008189715366a4"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+ "synstructure",
+]
+
+[[package]]
+name = "flate2"
+version = "1.0.22"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1e6988e897c1c9c485f43b47a529cef42fde0547f9d8d41a7062518f1d8fc53f"
+dependencies = [
+ "cfg-if 1.0.0",
+ "crc32fast",
+ "libc",
+ "miniz_oxide",
+]
+
+[[package]]
 name = "fnv"
 version = "1.0.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -473,6 +611,12 @@ dependencies = [
 ]
 
 [[package]]
+name = "gimli"
+version = "0.26.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "78cc372d058dcf6d5ecd98510e7fbc9e5aec4d21de70f65fea8fecebcd881bd4"
+
+[[package]]
 name = "glob"
 version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -742,6 +886,15 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b71991ff56294aa922b450139ee08b3bfc70982c6b2c7562771375cf73542dd4"
 
 [[package]]
+name = "jobserver"
+version = "0.1.24"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "af25a77299a7f711a01975c35a6a424eb6862092cc2d6c72c4ed6cbc56dfc1fa"
+dependencies = [
+ "libc",
+]
+
+[[package]]
 name = "js-sys"
 version = "0.3.55"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -824,6 +977,16 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2a60c7ce501c71e03a9c9c0d35b861413ae925bd979cc7a4e30d060069aaac8d"
 
 [[package]]
+name = "miniz_oxide"
+version = "0.4.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a92518e98c078586bc6c934028adcca4c92a53d6a958196de835170a01d84e4b"
+dependencies = [
+ "adler",
+ "autocfg",
+]
+
+[[package]]
 name = "mio"
 version = "0.6.23"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -944,6 +1107,15 @@ dependencies = [
 ]
 
 [[package]]
+name = "object"
+version = "0.27.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "67ac1d3f9a1d3616fd9a60c8d74296f22406a238b6a72f5cc1e6f314df4ffbf9"
+dependencies = [
+ "memchr",
+]
+
+[[package]]
 name = "once_cell"
 version = "1.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1276,6 +1448,12 @@ dependencies = [
 ]
 
 [[package]]
+name = "rustc-demangle"
+version = "0.1.21"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7ef03e0a2b150c7a90d01faf6254c9c48a41e95fb2a8c2ac1c6f0d2b9aefc342"
+
+[[package]]
 name = "rustc_version"
 version = "0.2.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1608,6 +1786,18 @@ dependencies = [
 ]
 
 [[package]]
+name = "synstructure"
+version = "0.12.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f36bdaa60a83aca3921b5259d5400cbf5e90fc51931376a9bd4a0eb79aa7210f"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+ "unicode-xid",
+]
+
+[[package]]
 name = "tempfile"
 version = "3.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1929,8 +2119,10 @@ dependencies = [
 name = "tricot"
 version = "0.1.0"
 dependencies = [
+ "accept-encoding-fork",
  "acme-micro",
  "anyhow",
+ "async-compression",
  "bytes 1.1.0",
  "chrono",
  "envy",
@@ -1941,7 +2133,6 @@ dependencies = [
  "hyper 0.14.15",
  "hyper-reverse-proxy",
  "hyper-rustls",
- "lazy_static",
  "log",
  "pretty_env_logger",
  "rcgen",
@@ -1954,7 +2145,7 @@ dependencies = [
  "structopt",
  "tokio 1.14.0",
  "tokio-rustls",
- "unicase",
+ "tokio-util",
 ]
 
 [[package]]
@@ -2262,3 +2453,32 @@ checksum = "e262a29d0e61ccf2b6190d7050d4b237535fc76ce4c1210d9caa316f71dffa75"
 dependencies = [
  "chrono",
 ]
+
+[[package]]
+name = "zstd"
+version = "0.7.0+zstd.1.4.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9428752481d8372e15b1bf779ea518a179ad6c771cca2d2c60e4fbff3cc2cd52"
+dependencies = [
+ "zstd-safe",
+]
+
+[[package]]
+name = "zstd-safe"
+version = "3.1.0+zstd.1.4.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5aa1926623ad7fe406e090555387daf73db555b948134b4d73eac5eb08fb666d"
+dependencies = [
+ "libc",
+ "zstd-sys",
+]
+
+[[package]]
+name = "zstd-sys"
+version = "1.5.0+zstd.1.4.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4e6c094340240369025fc6b731b054ee2a834328fa584310ac96aa4baebdc465"
+dependencies = [
+ "cc",
+ "libc",
+]
diff --git a/Cargo.toml b/Cargo.toml
index 2130197..9ed93c0 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -28,8 +28,9 @@ tokio-rustls = "0.23"
 hyper-rustls = "0.23"
 http = "0.2"
 hyper-reverse-proxy = "0.4"
-unicase = "2"
-lazy_static = "1.4"
 structopt = "0.3"
 glob = "0.3"
 rcgen = "0.8"
+accept-encoding-fork = "0.2.0-alpha.3"
+async-compression = { version = "0.3", features = ["tokio", "gzip", "zstd", "deflate", "brotli"] }
+tokio-util = { version = "0.6", features = ["io"] }
diff --git a/src/https.rs b/src/https.rs
index a389e72..1b467c0 100644
--- a/src/https.rs
+++ b/src/https.rs
@@ -1,44 +1,56 @@
+use std::convert::Infallible;
 use std::net::SocketAddr;
 use std::sync::{atomic::Ordering, Arc};
 
 use anyhow::Result;
 use log::*;
 
-use futures::FutureExt;
+use accept_encoding_fork::Encoding;
+use async_compression::tokio::bufread::*;
+use futures::TryStreamExt;
 use http::header::{HeaderName, HeaderValue};
 use hyper::server::conn::Http;
 use hyper::service::service_fn;
-use hyper::{Body, Request, Response, StatusCode};
+use hyper::{header, Body, Request, Response, StatusCode};
 use tokio::net::TcpListener;
 use tokio::sync::watch;
 use tokio_rustls::TlsAcceptor;
+use tokio_util::io::{ReaderStream, StreamReader};
 
 use crate::cert_store::{CertStore, StoreResolver};
 use crate::proxy_config::ProxyConfig;
 use crate::reverse_proxy;
 
+pub struct HttpsConfig {
+	pub bind_addr: SocketAddr,
+	pub enable_compression: bool,
+	pub compress_mime_types: Vec<String>,
+}
+
 pub async fn serve_https(
-	bind_addr: SocketAddr,
+	config: HttpsConfig,
 	cert_store: Arc<CertStore>,
-	proxy_config: watch::Receiver<Arc<ProxyConfig>>,
+	rx_proxy_config: watch::Receiver<Arc<ProxyConfig>>,
 ) -> Result<()> {
-	let mut cfg = rustls::ServerConfig::builder()
+	let config = Arc::new(config);
+
+	let mut tls_cfg = rustls::ServerConfig::builder()
 		.with_safe_defaults()
 		.with_no_client_auth()
 		.with_cert_resolver(Arc::new(StoreResolver(cert_store)));
 
-	cfg.alpn_protocols = vec![b"h2".to_vec(), b"http/1.1".to_vec()];
-	let tls_cfg = Arc::new(cfg);
-	let tls_acceptor = Arc::new(TlsAcceptor::from(tls_cfg));
+	tls_cfg.alpn_protocols = vec![b"h2".to_vec(), b"http/1.1".to_vec()];
+	let tls_acceptor = Arc::new(TlsAcceptor::from(Arc::new(tls_cfg)));
 
-	info!("Starting to serve on https://{}.", bind_addr);
+	info!("Starting to serve on https://{}.", config.bind_addr);
 
-	let tcp = TcpListener::bind(bind_addr).await?;
+	let tcp = TcpListener::bind(config.bind_addr).await?;
 	loop {
 		let (socket, remote_addr) = tcp.accept().await?;
 
-		let proxy_config = proxy_config.clone();
+		let rx_proxy_config = rx_proxy_config.clone();
 		let tls_acceptor = tls_acceptor.clone();
+		let config = config.clone();
 
 		tokio::spawn(async move {
 			match tls_acceptor.accept(socket).await {
@@ -48,17 +60,10 @@ pub async fn serve_https(
 						.serve_connection(
 							stream,
 							service_fn(move |req: Request<Body>| {
-								let proxy_config: Arc<ProxyConfig> = proxy_config.borrow().clone();
-								handle(remote_addr, req, proxy_config).map(|res| match res {
-									Err(e) => {
-										warn!("Handler error: {}", e);
-										Response::builder()
-											.status(StatusCode::INTERNAL_SERVER_ERROR)
-											.body(Body::from(format!("{}", e)))
-											.map_err(Into::into)
-									}
-									x => x,
-								})
+								let https_config = config.clone();
+								let proxy_config: Arc<ProxyConfig> =
+									rx_proxy_config.borrow().clone();
+								handle_outer(remote_addr, req, https_config, proxy_config)
 							}),
 						)
 						.await;
@@ -72,11 +77,30 @@ pub async fn serve_https(
 	}
 }
 
+async fn handle_outer(
+	remote_addr: SocketAddr,
+	req: Request<Body>,
+	https_config: Arc<HttpsConfig>,
+	proxy_config: Arc<ProxyConfig>,
+) -> Result<Response<Body>, Infallible> {
+	match handle(remote_addr, req, https_config, proxy_config).await {
+		Err(e) => {
+			warn!("Handler error: {}", e);
+			Ok(Response::builder()
+				.status(StatusCode::INTERNAL_SERVER_ERROR)
+				.body(Body::from(format!("{}", e)))
+				.unwrap())
+		}
+		Ok(r) => Ok(r),
+	}
+}
+
 // Custom echo service, handling two different routes and a
 // catch-all 404 responder.
 async fn handle(
 	remote_addr: SocketAddr,
 	req: Request<Body>,
+	https_config: Arc<HttpsConfig>,
 	proxy_config: Arc<ProxyConfig>,
 ) -> Result<Response<Body>, anyhow::Error> {
 	let method = req.method().clone();
@@ -91,6 +115,7 @@ async fn handle(
 			.to_str()?
 	};
 	let path = req.uri().path();
+	let accept_encoding = accept_encoding_fork::parse(req.headers()).unwrap_or(None);
 
 	let best_match = proxy_config
 		.entries
@@ -137,7 +162,11 @@ async fn handle(
 		trace!("Response: {:?}", response);
 		info!("{} {} {}", method, response.status().as_u16(), uri);
 
-		Ok(response)
+		if https_config.enable_compression {
+			try_compress(response, accept_encoding, &https_config)
+		} else {
+			Ok(response)
+		}
 	} else {
 		debug!("{}{} -> NOT FOUND", host, path);
 		info!("{} 404 {}", method, uri);
@@ -147,3 +176,61 @@ async fn handle(
 			.body(Body::from("No matching proxy entry"))?)
 	}
 }
+
+fn try_compress(
+	response: Response<Body>,
+	accept_encoding: Option<Encoding>,
+	https_config: &HttpsConfig,
+) -> Result<Response<Body>> {
+	// Check if a compression encoding is accepted
+	let encoding = match accept_encoding {
+		None | Some(Encoding::Identity) => return Ok(response),
+		Some(enc) => enc,
+	};
+
+	// If already compressed, return as is
+	if response.headers().get(header::CONTENT_ENCODING).is_some() {
+		return Ok(response);
+	}
+
+	// If content type not in mime types for which to compress, return as is
+	match response.headers().get(header::CONTENT_TYPE) {
+		Some(ct) => {
+			let ct_str = ct.to_str()?;
+			if !https_config.compress_mime_types.iter().any(|x| x == ct_str) {
+				return Ok(response);
+			}
+		}
+		None => return Ok(response),
+	};
+
+	debug!("Compressing response body as {:?}", encoding);
+
+	let (mut head, body) = response.into_parts();
+	let body_rd =
+		StreamReader::new(body.map_err(|e| std::io::Error::new(std::io::ErrorKind::Other, e)));
+	let compressed_body = match encoding {
+		Encoding::Gzip => {
+			head.headers
+				.insert(header::CONTENT_ENCODING, "gzip".parse()?);
+			Body::wrap_stream(ReaderStream::new(GzipEncoder::new(body_rd)))
+		}
+		Encoding::Brotli => {
+			head.headers.insert(header::CONTENT_ENCODING, "br".parse()?);
+			Body::wrap_stream(ReaderStream::new(BrotliEncoder::new(body_rd)))
+		}
+		Encoding::Deflate => {
+			head.headers
+				.insert(header::CONTENT_ENCODING, "deflate".parse()?);
+			Body::wrap_stream(ReaderStream::new(DeflateEncoder::new(body_rd)))
+		}
+		Encoding::Zstd => {
+			head.headers
+				.insert(header::CONTENT_ENCODING, "zstd".parse()?);
+			Body::wrap_stream(ReaderStream::new(ZstdEncoder::new(body_rd)))
+		}
+		_ => unreachable!(),
+	};
+
+	Ok(Response::from_parts(head, compressed_body))
+}
diff --git a/src/main.rs b/src/main.rs
index 61fc747..febe540 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -58,6 +58,18 @@ struct Opt {
 	/// E-mail address for Let's Encrypt certificate requests
 	#[structopt(long = "letsencrypt-email", env = "TRICOT_LETSENCRYPT_EMAIL")]
 	pub letsencrypt_email: String,
+
+	/// Enable compression of responses
+	#[structopt(long = "enable-compression", env = "TRICOT_ENABLE_COMPRESSION")]
+	pub enable_compression: bool,
+
+	/// Mime types for which to enable compression (comma-separated list)
+	#[structopt(
+		long = "compress-mime-types",
+		env = "TRICOT_COMPRESS_MIME_TYPES",
+		default_value = "text/html,text/plain,text/css,text/javascript,application/javascript,image/svg+xml"
+	)]
+	pub compress_mime_types: String,
 }
 
 #[tokio::main(flavor = "multi_thread", worker_threads = 10)]
@@ -87,13 +99,19 @@ async fn main() {
 	);
 
 	tokio::spawn(http::serve_http(opt.http_bind_addr, consul.clone()).map_err(exit_on_err));
+
+	let https_config = https::HttpsConfig {
+		bind_addr: opt.https_bind_addr,
+		enable_compression: opt.enable_compression,
+		compress_mime_types: opt
+			.compress_mime_types
+			.split(",")
+			.map(|x| x.to_string())
+			.collect(),
+	};
 	tokio::spawn(
-		https::serve_https(
-			opt.https_bind_addr,
-			cert_store.clone(),
-			rx_proxy_config.clone(),
-		)
-		.map_err(exit_on_err),
+		https::serve_https(https_config, cert_store.clone(), rx_proxy_config.clone())
+			.map_err(exit_on_err),
 	);
 
 	while rx_proxy_config.changed().await.is_ok() {
diff --git a/src/reverse_proxy.rs b/src/reverse_proxy.rs
index 72644b7..445f6ef 100644
--- a/src/reverse_proxy.rs
+++ b/src/reverse_proxy.rs
@@ -12,33 +12,25 @@ use log::*;
 
 use http::header::HeaderName;
 use hyper::header::{HeaderMap, HeaderValue};
-use hyper::{Body, Client, Request, Response, Uri};
-use lazy_static::lazy_static;
+use hyper::{header, Body, Client, Request, Response, Uri};
 use rustls::client::{ServerCertVerified, ServerCertVerifier};
 use rustls::{Certificate, ServerName};
 
 use crate::tls_util::HttpsConnectorFixedDnsname;
 
-fn is_hop_header(name: &str) -> bool {
-	use unicase::Ascii;
-
-	// A list of the headers, using `unicase` to help us compare without
-	// worrying about the case, and `lazy_static!` to prevent reallocation
-	// of the vector.
-	lazy_static! {
-		static ref HOP_HEADERS: Vec<Ascii<&'static str>> = vec![
-			Ascii::new("Connection"),
-			Ascii::new("Keep-Alive"),
-			Ascii::new("Proxy-Authenticate"),
-			Ascii::new("Proxy-Authorization"),
-			Ascii::new("Te"),
-			Ascii::new("Trailers"),
-			Ascii::new("Transfer-Encoding"),
-			Ascii::new("Upgrade"),
-		];
-	}
-
-	HOP_HEADERS.iter().any(|h| h == &name)
+const HOP_HEADERS: &[HeaderName] = &[
+	header::CONNECTION,
+	//header::KEEP_ALIVE,
+	header::PROXY_AUTHENTICATE,
+	header::PROXY_AUTHORIZATION,
+	header::TE,
+	header::TRAILER,
+	header::TRANSFER_ENCODING,
+	header::UPGRADE,
+];
+
+fn is_hop_header(name: &HeaderName) -> bool {
+	HOP_HEADERS.iter().any(|h| h == name)
 }
 
 /// Returns a clone of the headers without the [hop-by-hop headers].
@@ -47,7 +39,7 @@ fn is_hop_header(name: &str) -> bool {
 fn remove_hop_headers(headers: &HeaderMap<HeaderValue>) -> HeaderMap<HeaderValue> {
 	let mut result = HeaderMap::new();
 	for (k, v) in headers.iter() {
-		if !is_hop_header(k.as_str()) {
+		if !is_hop_header(&k) {
 			result.append(k.clone(), v.clone());
 		}
 	}
@@ -80,10 +72,7 @@ fn create_proxied_request<B>(
 	*builder.headers_mut().unwrap() = remove_hop_headers(request.headers());
 
 	// If request does not have host header, add it from original URI authority
-	let host_header_name = "host";
-	if let hyper::header::Entry::Vacant(entry) =
-		builder.headers_mut().unwrap().entry(host_header_name)
-	{
+	if let header::Entry::Vacant(entry) = builder.headers_mut().unwrap().entry(header::HOST) {
 		if let Some(authority) = request.uri().authority() {
 			entry.insert(authority.as_str().parse()?);
 		}
@@ -96,11 +85,11 @@ fn create_proxied_request<B>(
 		.unwrap()
 		.entry(x_forwarded_for_header_name)
 	{
-		hyper::header::Entry::Vacant(entry) => {
+		header::Entry::Vacant(entry) => {
 			entry.insert(client_ip.to_string().parse()?);
 		}
 
-		hyper::header::Entry::Occupied(mut entry) => {
+		header::Entry::Occupied(mut entry) => {
 			let addr = format!("{}, {}", entry.get().to_str()?, client_ip);
 			entry.insert(addr.parse()?);
 		}
@@ -112,17 +101,17 @@ fn create_proxied_request<B>(
 	);
 
 	// Proxy upgrade requests properly
-	if let Some(conn) = request.headers().get("connection") {
+	if let Some(conn) = request.headers().get(header::CONNECTION) {
 		if conn.to_str()?.to_lowercase() == "upgrade" {
-			if let Some(upgrade) = request.headers().get("upgrade") {
-				builder.headers_mut().unwrap().insert(
-					HeaderName::from_bytes(b"connection")?,
-					"Upgrade".try_into()?,
-				);
+			if let Some(upgrade) = request.headers().get(header::UPGRADE) {
+				builder
+					.headers_mut()
+					.unwrap()
+					.insert(header::CONNECTION, "Upgrade".try_into()?);
 				builder
 					.headers_mut()
 					.unwrap()
-					.insert(HeaderName::from_bytes(b"upgrade")?, upgrade.clone());
+					.insert(header::UPGRADE, upgrade.clone());
 			}
 		}
 	}