Repository: algesten/ureq (rust)

Issue:
header: disallow white space between field name and colon
https://tools.ietf.org/html/rfc7230#section-3.2.4
>    No whitespace is allowed between the header field-name and colon.  In
   the past, differences in the handling of such whitespace have led to
   security vulnerabilities in request routing and response handling.  A
   server MUST reject any received request message that contains
   whitespace between a header field-name and colon with a response code
   of 400 (Bad Request).  A proxy MUST remove any such whitespace from a
   response message before forwarding the message downstream.

Pull request:
Validate header field names.
This rejects spaces after field names as well as various other invalid
characters.

Fixes #96 

Patch:
diff --git a/Cargo.toml b/Cargo.toml
index 408b9ce..5e082fe 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -33,7 +33,7 @@ url = "2"
 socks = { version = "0.3.2", optional = true }
 rustls = { version = "0.17", optional = true, features = [] }
 webpki = { version = "0.21", optional = true }
-webpki-roots = { version = "0.19", optional = true }
+webpki-roots = { version = "0.20", optional = true }
 rustls-native-certs = { version = "0.3", optional = true }
 serde = { version = "1", optional = true }
 serde_json = { version = "1", optional = true }
diff --git a/src/header.rs b/src/header.rs
index 056a4b8..719ccb9 100644
--- a/src/header.rs
+++ b/src/header.rs
@@ -2,9 +2,15 @@ use crate::error::Error;
 use std::str::FromStr;
 
 #[derive(Clone)]
-/// Wrapper type for a header line.
+/// Wrapper type for a header field.
+/// https://tools.ietf.org/html/rfc7230#section-3.2
 pub struct Header {
+    // Line contains the unmodified bytes of single header field.
+    // It does not contain the final CRLF.
     line: String,
+    // Index is the position of the colon within the header field.
+    // Invariant: index > 0
+    // Invariant: index + 1 < line.len()
     index: usize,
 }
 
@@ -82,6 +88,29 @@ pub fn add_header(headers: &mut Vec<Header>, header: Header) {
     headers.push(header);
 }
 
+// https://tools.ietf.org/html/rfc7230#section-3.2.3
+// Each header field consists of a case-insensitive field name followed
+// by a colon (":"), optional leading whitespace, the field value, and
+// optional trailing whitespace.
+// field-name     = token
+// token = 1*tchar
+// tchar = "!" / "#" / "$" / "%" / "&" / "'" / "*" / "+" / "-" / "." /
+// "^" / "_" / "`" / "|" / "~" / DIGIT / ALPHA
+fn valid_name(name: &str) -> bool {
+    name.len() > 0 && name.bytes().all(is_tchar)
+}
+
+#[inline]
+fn is_tchar(b: u8) -> bool {
+    match b {
+        b'!' | b'#' | b'$' | b'%' | b'&' => true,
+        b'\'' | b'*' | b'+' | b'-' | b'.' => true,
+        b'^' | b'_' | b'`' | b'|' | b'~' => true,
+        b if b.is_ascii_alphanumeric() => true,
+        _ => false,
+    }
+}
+
 impl FromStr for Header {
     type Err = Error;
     fn from_str(s: &str) -> Result<Self, Self::Err> {
@@ -94,16 +123,43 @@ impl FromStr for Header {
             return Err(Error::BadHeader);
         }
 
-        // https://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.2
-        // The field value MAY be preceded by any amount of LWS, though a single SP is preferred.
-        let value_from = &s[index..];
-        let voff = match value_from.find(|c: char| !c.is_whitespace()) {
-            Some(n) => n,
-            None => 0,
-        };
-
-        let index = index + voff;
+        if !valid_name(&line[0..index]) {
+            return Err(Error::BadHeader);
+        }
 
         Ok(Header { line, index })
     }
 }
+
+#[test]
+fn test_valid_name() {
+    assert!(valid_name("example"));
+    assert!(valid_name("Content-Type"));
+    assert!(valid_name("h-123456789"));
+    assert!(!valid_name("Content-Type:"));
+    assert!(!valid_name("Content-Type "));
+    assert!(!valid_name(" some-header"));
+    assert!(!valid_name("\"invalid\""));
+    assert!(!valid_name("Gödel"));
+}
+
+#[test]
+fn test_parse_invalid_name() {
+    let h = "Content-Type   :".parse::<Header>();
+    match h {
+        Err(Error::BadHeader) => {}
+        h => assert!(false, "expected BadHeader error, got {:?}", h),
+    }
+}
+
+#[test]
+fn empty_value() {
+    let h = "foo:".parse::<Header>().unwrap();
+    assert_eq!(h.value(), "");
+}
+
+#[test]
+fn value_with_whitespace() {
+    let h = "foo:      bar    ".parse::<Header>().unwrap();
+    assert_eq!(h.value(), "bar");
+}


Test patch:
diff --git a/src/test/agent_test.rs b/src/test/agent_test.rs
index 55934b9..66356cd 100644
--- a/src/test/agent_test.rs
+++ b/src/test/agent_test.rs
@@ -1,6 +1,7 @@
 use crate::test;
-use std::io::{BufRead, BufReader, Read, Write};
-use std::thread;
+use crate::test::testserver::{read_headers, TestServer};
+use std::io::{self, Write};
+use std::net::TcpStream;
 use std::time::Duration;
 
 use super::super::*;
@@ -56,47 +57,25 @@ fn agent_cookies() {
     agent.get("test://host/agent_cookies").call();
 }
 
-// Start a test server on an available port, that times out idle connections at 2 seconds.
-// Return the port this server is listening on.
-fn start_idle_timeout_server() -> u16 {
-    let listener = std::net::TcpListener::bind("localhost:0").unwrap();
-    let port = listener.local_addr().unwrap().port();
-    thread::spawn(move || {
-        for stream in listener.incoming() {
-            thread::spawn(move || {
-                let stream = stream.unwrap();
-                stream
-                    .set_read_timeout(Some(Duration::from_secs(2)))
-                    .unwrap();
-                let mut write_stream = stream.try_clone().unwrap();
-                for line in BufReader::new(stream).lines() {
-                    let line = match line {
-                        Ok(x) => x,
-                        Err(_) => return,
-                    };
-                    if line == "" {
-                        write_stream
-                            .write_all(b"HTTP/1.1 200 OK\r\nContent-Length: 8\r\n\r\nresponse")
-                            .unwrap();
-                    }
-                }
-            });
-        }
-    });
-    port
+// Handler that answers with a simple HTTP response, and times
+// out idle connections after 2 seconds.
+fn idle_timeout_handler(mut stream: TcpStream) -> io::Result<()> {
+    read_headers(&stream);
+    stream.write_all(b"HTTP/1.1 200 OK\r\nContent-Length: 8\r\n\r\nresponse")?;
+    stream.set_read_timeout(Some(Duration::from_secs(2)))?;
+    Ok(())
 }
 
 #[test]
 fn connection_reuse() {
-    let port = start_idle_timeout_server();
-    let url = format!("http://localhost:{}", port);
+    let testserver = TestServer::new(idle_timeout_handler);
+    let url = format!("http://localhost:{}", testserver.port);
     let agent = Agent::default().build();
     let resp = agent.get(&url).call();
 
     // use up the connection so it gets returned to the pool
     assert_eq!(resp.status(), 200);
-    let mut buf = vec![];
-    resp.into_reader().read_to_end(&mut buf).unwrap();
+    resp.into_string().unwrap();
 
     {
         let mut guard_state = agent.state.lock().unwrap();
diff --git a/src/test/mod.rs b/src/test/mod.rs
index 2baa08f..801b7c9 100644
--- a/src/test/mod.rs
+++ b/src/test/mod.rs
@@ -14,6 +14,7 @@ mod query_string;
 mod range;
 mod redirect;
 mod simple;
+mod testserver;
 mod timeout;
 
 type RequestHandler = dyn Fn(&Unit) -> Result<Stream, Error> + Send + 'static;
diff --git a/src/test/testserver.rs b/src/test/testserver.rs
new file mode 100644
index 0000000..7c563a1
--- /dev/null
+++ b/src/test/testserver.rs
@@ -0,0 +1,50 @@
+use std::io::{self, BufRead, BufReader};
+use std::net::{TcpListener, TcpStream};
+use std::sync::atomic::{AtomicBool, Ordering};
+use std::sync::Arc;
+use std::thread;
+
+pub struct TestServer {
+    pub port: u16,
+    pub done: Arc<AtomicBool>,
+}
+
+// Read a stream until reaching a blank line, in order to consume
+// request headers.
+pub fn read_headers(stream: &TcpStream) {
+    for line in BufReader::new(stream).lines() {
+        if line.unwrap() == "" {
+            break;
+        }
+    }
+}
+
+impl TestServer {
+    pub fn new(handler: fn(TcpStream) -> io::Result<()>) -> Self {
+        let listener = TcpListener::bind("localhost:0").unwrap();
+        let port = listener.local_addr().unwrap().port();
+        let done = Arc::new(AtomicBool::new(false));
+        let done_clone = done.clone();
+        thread::spawn(move || {
+            for stream in listener.incoming() {
+                thread::spawn(move || handler(stream.unwrap()));
+                if done.load(Ordering::Relaxed) {
+                    break;
+                }
+            }
+            println!("testserver on {} exiting", port);
+        });
+        TestServer {
+            port,
+            done: done_clone,
+        }
+    }
+}
+
+impl Drop for TestServer {
+    fn drop(&mut self) {
+        self.done.store(true, Ordering::Relaxed);
+        // Connect once to unblock the listen loop.
+        TcpStream::connect(format!("localhost:{}", self.port)).unwrap();
+    }
+}
diff --git a/src/test/timeout.rs b/src/test/timeout.rs
index 4e14df5..0ccafca 100644
--- a/src/test/timeout.rs
+++ b/src/test/timeout.rs
@@ -1,4 +1,5 @@
-use std::io::{self, BufRead, BufReader, Read, Write};
+use crate::test::testserver::*;
+use std::io::{self, Write};
 use std::net::TcpStream;
 use std::thread;
 use std::time::Duration;
@@ -7,7 +8,8 @@ use super::super::*;
 
 // Send an HTTP response on the TcpStream at a rate of two bytes every 10
 // milliseconds, for a total of 600 bytes.
-fn dribble_body_respond(stream: &mut TcpStream) -> io::Result<()> {
+fn dribble_body_respond(mut stream: TcpStream) -> io::Result<()> {
+    read_headers(&stream);
     let contents = [b'a'; 300];
     let headers = format!(
         "HTTP/1.1 200 OK\r\nContent-Length: {}\r\n\r\n",
@@ -23,49 +25,12 @@ fn dribble_body_respond(stream: &mut TcpStream) -> io::Result<()> {
     Ok(())
 }
 
-// Read a stream until reaching a blank line, in order to consume
-// request headers.
-fn read_headers(stream: &TcpStream) {
-    for line in BufReader::new(stream).lines() {
-        let line = match line {
-            Ok(x) => x,
-            Err(_) => return,
-        };
-        if line == "" {
-            break;
-        }
-    }
-}
-
-// Start a test server on an available port, that dribbles out a response at 1 write per 10ms.
-// Return the port this server is listening on.
-fn start_dribble_body_server() -> u16 {
-    let listener = std::net::TcpListener::bind("localhost:0").unwrap();
-    let port = listener.local_addr().unwrap().port();
-    let dribble_handler = |mut stream: TcpStream| {
-        read_headers(&stream);
-        if let Err(e) = dribble_body_respond(&mut stream) {
-            eprintln!("sending dribble repsonse: {}", e);
-        }
-    };
-    thread::spawn(move || {
-        for stream in listener.incoming() {
-            thread::spawn(move || dribble_handler(stream.unwrap()));
-        }
-    });
-    port
-}
-
 fn get_and_expect_timeout(url: String) {
     let agent = Agent::default().build();
     let timeout = Duration::from_millis(500);
     let resp = agent.get(&url).timeout(timeout).call();
 
-    let mut reader = resp.into_reader();
-    let mut bytes = vec![];
-    let result = reader.read_to_end(&mut bytes);
-
-    match result {
+    match resp.into_string() {
         Err(io_error) => match io_error.kind() {
             io::ErrorKind::WouldBlock => Ok(()),
             io::ErrorKind::TimedOut => Ok(()),
@@ -78,15 +43,15 @@ fn get_and_expect_timeout(url: String) {
 
 #[test]
 fn overall_timeout_during_body() {
-    let port = start_dribble_body_server();
-    let url = format!("http://localhost:{}/", port);
-
+    // Start a test server on an available port, that dribbles out a response at 1 write per 10ms.
+    let server = TestServer::new(dribble_body_respond);
+    let url = format!("http://localhost:{}/", server.port);
     get_and_expect_timeout(url);
 }
 
 // Send HTTP headers on the TcpStream at a rate of one header every 100
 // milliseconds, for a total of 30 headers.
-fn dribble_headers_respond(stream: &mut TcpStream) -> io::Result<()> {
+fn dribble_headers_respond(mut stream: TcpStream) -> io::Result<()> {
     stream.write_all(b"HTTP/1.1 200 OK\r\nContent-Length: 0\r\n")?;
     for _ in 0..30 {
         stream.write_all(b"a: b\n")?;
@@ -96,28 +61,10 @@ fn dribble_headers_respond(stream: &mut TcpStream) -> io::Result<()> {
     Ok(())
 }
 
-// Start a test server on an available port, that dribbles out response *headers* at 1 write per 10ms.
-// Return the port this server is listening on.
-fn start_dribble_headers_server() -> u16 {
-    let listener = std::net::TcpListener::bind("localhost:0").unwrap();
-    let port = listener.local_addr().unwrap().port();
-    let dribble_handler = |mut stream: TcpStream| {
-        read_headers(&stream);
-        if let Err(e) = dribble_headers_respond(&mut stream) {
-            eprintln!("sending dribble repsonse: {}", e);
-        }
-    };
-    thread::spawn(move || {
-        for stream in listener.incoming() {
-            thread::spawn(move || dribble_handler(stream.unwrap()));
-        }
-    });
-    port
-}
-
 #[test]
 fn overall_timeout_during_headers() {
-    let port = start_dribble_headers_server();
-    let url = format!("http://localhost:{}/", port);
+    // Start a test server on an available port, that dribbles out a response at 1 write per 10ms.
+    let server = TestServer::new(dribble_headers_respond);
+    let url = format!("http://localhost:{}/", server.port);
     get_and_expect_timeout(url);
 }