correctly adhere to spec in most request cases

README.md

@@ -63,6 +63,19 @@ Note: This sets the user to `nobody` and the group to `nobody` as well. This
 naming scheme is not consistent for all Unix systems... Try changing the group
 name to `nogroup` if the software fails to start.
 
+Testing
+-------
+
+As you may have spotted, I did not get around to write a test suite for this.
+The server's behavior can be tested using the
+[gemini-diagnostics](https://github.com/michael-lazar/gemini-diagnostics) suite
+by michael-lazar. It passes all "important" tests (some malformed requests
+are still handled). Most importantly: the URLDotEscape tests fails. This does
+not mean you can successfully a URL escape attack against this, rather the URL
+library I use already parses out any superfluous ..'s.
+e.g. "localhost/../../../etc/passwd" already became "localhost/etc/passwd" once
+I receive the parsed URL from the library.
+
 Why "Sheldon Director"?
 -----------------------
 

doc/sheldond.conf

@@ -5,8 +5,8 @@ default_host = localhost
 gem_root = ./doc
 
 # you can define as many of these as you like
-listen = [::1]:1965
-listen = 127.0.0.1:1965
+listen = 0.0.0.0:1965
+listen = [::]:1965
 
 # privilege level for the server to drop to after initializing
 user = nobody

src/server/handler.rs

@@ -20,11 +20,10 @@ fn send_header(stream: &mut SslStream<TcpStream>, header: &response::Header) {
 }
 
 pub fn handle_request(config: &ServerConfig, mut stream: SslStream<TcpStream>) {
-    let mut buffer = [0; 1026];
+    let mut buffer = [0; 1024];
     match stream.ssl_read(&mut buffer) {
         Ok(s) => {
-            if s == 0 {
-                println!("received empty request buffer");
+            if s == 0 || s > 1025 {
                 send_header(&mut stream, &response::bad_request());
                 return;
             }
@@ -47,7 +46,11 @@ pub fn handle_request(config: &ServerConfig, mut stream: SslStream<TcpStream>) {
 
     let location = match Url::parse(&request) {
         Ok(url) => url,
-        Err(_) => config.default_host.join(&request).unwrap(),
+        Err(_) => {
+            println!("received invalid request url");
+            send_header(&mut stream, &response::bad_request());
+            return;
+        },
     };
 
     handle_response(config, location, &mut stream);
@@ -69,25 +72,39 @@ fn write_line<T: Write>(line: &[u8], stream: &mut BufWriter<T>) -> Result<(), Er
 fn handle_response(config: &ServerConfig, url: Url, mut stream: &mut SslStream<TcpStream>) {
     println!("responding for: {}", url);
 
-    if url.scheme() != "gemini" {
-        send_header(&mut stream, &response::permanent_failure());
+    // url scheme must be either "gemini://" or "//" (empty)
+    if url.scheme() != "gemini" && url.scheme() != "" {
+        send_header(&mut stream, &response::proxy_request_refused());
         return;
     }
 
+    // url request host must match
     if url.host() != config.default_host.host() {
         send_header(&mut stream, &response::proxy_request_refused());
         return;
     }
 
+    // TODO: also drop on incorrect port in request
+
     let rel_path = match Path::new(url.path()).strip_prefix("/") {
         Ok(path) => path,
         Err(_) => {
-            Path::new("")
+            // empty path, gemini spec says to redirect client to root
+            send_header(&mut stream, &response::redirect_permanent(
+                config.default_host.as_str(),
+            ));
+            return;
         }
     };
 
     let path = gen_path_index(&config.gem_root.join(rel_path));
 
+    // make sure we can't escape gem_root
+    if !path.starts_with(&config.gem_root) {
+        send_header(&mut stream, &response::bad_request());
+        return;
+    }
+
     let file = match File::open(&path) {
         Ok(file) => file,
         Err(_) => {

src/server/mod.rs

@@ -24,7 +24,7 @@ pub struct ServerConfig {
 impl ServerConfig {
     pub fn new() -> ServerConfig {
         ServerConfig {
-            default_host: Url::parse("gemini://localhost").unwrap(),
+            default_host: Url::parse("gemini://localhost/").unwrap(),
             gem_root: PathBuf::from(""),
             addrs: Vec::new(),
             user: unistd::getuid(),
@@ -35,7 +35,7 @@ impl ServerConfig {
     }
 
     pub fn set_default_host(&mut self, default_host: String) {
-        let mut url = Url::parse("gemini://default").unwrap();
+        let mut url = Url::parse("gemini://default/").unwrap();
 
         match url.set_host(Some(default_host.as_str())) {
             Ok(_) => {}

src/server/response.rs

@@ -3,6 +3,7 @@ use std::vec::Vec;
 #[derive(Copy, Clone)]
 pub enum Status {
     Success = 20,
+    RedirectPermanent = 31,
     PermanentFailure = 50,
     NotFound = 51,
     ProxyRequestRefused = 53,
@@ -31,6 +32,10 @@ impl Header {
     }
 }
 
+pub fn redirect_permanent(meta: &str) -> Header {
+    Header::new(Status::RedirectPermanent, meta)
+}
+
 pub fn permanent_failure() -> Header {
     Header::new(Status::PermanentFailure, "permanent failure")
 }
@@ -46,3 +51,4 @@ pub fn proxy_request_refused() -> Header {
 pub fn bad_request() -> Header {
     Header::new(Status::BadRequest, "bad request")
 }
+