Async handshake

Cargo.lock

@@ -29,6 +29,12 @@ dependencies = [
  "generic-array",
 ]
 
+[[package]]
+name = "bytes"
+version = "1.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b35204fbdc0b3f4446b89fc1ac2cf84a8a68971995d0bf2e925ec7cd960f9cb3"
+
 [[package]]
 name = "cfg-if"
 version = "1.0.4"
@@ -189,6 +195,23 @@ version = "2.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f8ca58f447f06ed17d5fc4043ce1b10dd205e060fb3ce5b979b8ed8e59ff3f79"
 
+[[package]]
+name = "mio"
+version = "1.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a69bcab0ad47271a0234d9422b131806bf3968021e5dc9328caf2d4cd58557fc"
+dependencies = [
+ "libc",
+ "wasi",
+ "windows-sys 0.61.2",
+]
+
+[[package]]
+name = "pin-project-lite"
+version = "0.2.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3b3cff922bd51709b605d9ead9aa71031d81447142d828eb4a6eba76fe619f9b"
+
 [[package]]
 name = "prettyplease"
 version = "0.2.37"
@@ -297,6 +320,7 @@ dependencies = [
  "serde",
  "serde_json",
  "sha1",
+ "tokio",
 ]
 
 [[package]]
@@ -310,6 +334,16 @@ dependencies = [
  "digest",
 ]
 
+[[package]]
+name = "socket2"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "17129e116933cf371d018bb80ae557e889637989d8638274fb25622827b03881"
+dependencies = [
+ "libc",
+ "windows-sys 0.60.2",
+]
+
 [[package]]
 name = "syn"
 version = "2.0.116"
@@ -321,6 +355,20 @@ dependencies = [
  "unicode-ident",
 ]
 
+[[package]]
+name = "tokio"
+version = "1.49.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "72a2903cd7736441aac9df9d7688bd0ce48edccaadf181c3b90be801e81d3d86"
+dependencies = [
+ "bytes",
+ "libc",
+ "mio",
+ "pin-project-lite",
+ "socket2",
+ "windows-sys 0.61.2",
+]
+
 [[package]]
 name = "typenum"
 version = "1.19.0"
@@ -345,6 +393,12 @@ version = "0.9.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0b928f33d975fc6ad9f86c8f283853ad26bdd5b10b7f1542aa2fa15e2289105a"
 
+[[package]]
+name = "wasi"
+version = "0.11.1+wasi-snapshot-preview1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ccf3ec651a847eb01de73ccad15eb7d99f80485de043efb2f370cd654f4ea44b"
+
 [[package]]
 name = "wasip2"
 version = "1.0.2+wasi-0.2.9"
@@ -397,6 +451,95 @@ dependencies = [
  "semver",
 ]
 
+[[package]]
+name = "windows-link"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f0805222e57f7521d6a62e36fa9163bc891acd422f971defe97d64e70d0a4fe5"
+
+[[package]]
+name = "windows-sys"
+version = "0.60.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f2f500e4d28234f72040990ec9d39e3a6b950f9f22d3dba18416c35882612bcb"
+dependencies = [
+ "windows-targets",
+]
+
+[[package]]
+name = "windows-sys"
+version = "0.61.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ae137229bcbd6cdf0f7b80a31df61766145077ddf49416a728b02cb3921ff3fc"
+dependencies = [
+ "windows-link",
+]
+
+[[package]]
+name = "windows-targets"
+version = "0.53.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4945f9f551b88e0d65f3db0bc25c33b8acea4d9e41163edf90dcd0b19f9069f3"
+dependencies = [
+ "windows-link",
+ "windows_aarch64_gnullvm",
+ "windows_aarch64_msvc",
+ "windows_i686_gnu",
+ "windows_i686_gnullvm",
+ "windows_i686_msvc",
+ "windows_x86_64_gnu",
+ "windows_x86_64_gnullvm",
+ "windows_x86_64_msvc",
+]
+
+[[package]]
+name = "windows_aarch64_gnullvm"
+version = "0.53.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a9d8416fa8b42f5c947f8482c43e7d89e73a173cead56d044f6a56104a6d1b53"
+
+[[package]]
+name = "windows_aarch64_msvc"
+version = "0.53.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b9d782e804c2f632e395708e99a94275910eb9100b2114651e04744e9b125006"
+
+[[package]]
+name = "windows_i686_gnu"
+version = "0.53.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "960e6da069d81e09becb0ca57a65220ddff016ff2d6af6a223cf372a506593a3"
+
+[[package]]
+name = "windows_i686_gnullvm"
+version = "0.53.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fa7359d10048f68ab8b09fa71c3daccfb0e9b559aed648a8f95469c27057180c"
+
+[[package]]
+name = "windows_i686_msvc"
+version = "0.53.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1e7ac75179f18232fe9c285163565a57ef8d3c89254a30685b57d83a38d326c2"
+
+[[package]]
+name = "windows_x86_64_gnu"
+version = "0.53.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9c3842cdd74a865a8066ab39c8a7a473c0778a3f29370b5fd6b4b9aa7df4a499"
+
+[[package]]
+name = "windows_x86_64_gnullvm"
+version = "0.53.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0ffa179e2d07eee8ad8f57493436566c7cc30ac536a3379fdf008f47f6bb7ae1"
+
+[[package]]
+name = "windows_x86_64_msvc"
+version = "0.53.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d6bbff5f0aada427a1e5a6da5f1f98158182f26556f345ac9e04d36d0ebed650"
+
 [[package]]
 name = "wit-bindgen"
 version = "0.51.0"

Cargo.toml

@@ -9,3 +9,4 @@ rand = "0.10.0"
 serde = "1.0.228"
 serde_json = "1.0.149"
 sha1 = "0.10.6"
+tokio = { version = "1.49.0", features = ["io-util", "net"] }

src/handshake.rs

@@ -0,0 +1,77 @@
+use tokio::{
+    io::{AsyncBufReadExt, AsyncWriteExt, BufReader},
+    net::TcpStream,
+};
+
+pub async fn handle_websocket_handshake(stream: &mut TcpStream) -> std::io::Result<()> {
+    let (read_half, mut write_half) = stream.split();
+    let mut reader = BufReader::new(read_half);
+
+    let mut request_line = String::new();
+    reader.read_line(&mut request_line).await?;
+    let request_line = request_line.trim_end();
+
+    if request_line.starts_with("HEAD") {
+        write_half
+            .write_all(b"HTTP/1.1 200 OK\r\nContent-Length: 0\r\n\r\n")
+            .await?;
+        return Ok(());
+    }
+
+    if !request_line.starts_with("GET") {
+        return Err(std::io::Error::new(
+            std::io::ErrorKind::InvalidData,
+            "Invalid HTTP method",
+        ));
+    }
+
+    use std::collections::HashMap;
+    let mut headers = HashMap::new();
+    let mut line = String::new();
+
+    loop {
+        line.clear();
+        reader.read_line(&mut line).await?;
+        if line == "\r\n" {
+            break;
+        }
+        if let Some((k, v)) = line.split_once(':') {
+            headers.insert(k.trim().to_lowercase(), v.trim().to_string());
+        }
+    }
+
+    if headers
+        .get("upgrade")
+        .map(|v| !v.eq_ignore_ascii_case("websocket"))
+        .unwrap_or(true)
+    {
+        write_half
+            .write_all(b"HTTP/1.1 200 OK\r\nContent-Length: 2\r\n\r\nOK")
+            .await?;
+        return Ok(());
+    }
+
+    let key = headers
+        .get("sec-websocket-key")
+        .ok_or_else(|| std::io::Error::new(std::io::ErrorKind::InvalidData, "Missing key"))?;
+
+    use base64::Engine;
+    use base64::engine::general_purpose::STANDARD as Base64;
+    use sha1::{Digest, Sha1};
+
+    let mut hasher = Sha1::new();
+    hasher.update(key.as_bytes());
+    hasher.update(b"258EAFA5-E914-47DA-95CA-C5AB0DC85B11");
+    let accept = Base64.encode(hasher.finalize());
+
+    let response = format!(
+        "HTTP/1.1 101 Switching Protocols\r\n\
+         Upgrade: websocket\r\n\
+         Connection: Upgrade\r\n\
+         Sec-WebSocket-Accept: {}\r\n\r\n",
+        accept
+    );
+
+    write_half.write_all(response.as_bytes()).await?;
+    Ok(())
+}

src/lib.rs

@@ -1,3 +1,4 @@
+pub mod handshake;
 pub mod server;
 pub mod session;
 

src/session.rs

@@ -8,124 +8,12 @@ use serde::{Deserialize, Serialize};
 
 use crate::SessionMessage;
 
-pub mod handshake {
-    use base64::Engine;
-    use base64::engine::general_purpose::STANDARD as Base64;
-    use sha1::{Digest, Sha1};
-    use std::collections::HashMap;
-    use std::io::{BufRead, BufReader, Write};
-    use std::net::TcpStream;
-
-    const WS_GUID: &str = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
-
-    pub fn handle_websocket_handshake(stream: &mut TcpStream) -> std::io::Result<()> {
-        let mut reader = BufReader::new(stream.try_clone()?);
-        let mut request_line = String::new();
-        reader.read_line(&mut request_line)?;
-
-        // Trim CRLF to make sure comparisons are clean
-        let request_line = request_line.trim_end();
-
-        // Allow HEAD (used by Render for health checks)
-        if request_line.starts_with("HEAD") {
-            let response = "HTTP/1.1 200 OK\r\nContent-Length: 0\r\n\r\n";
-            stream.write_all(response.as_bytes())?;
-            stream.flush()?;
-            return Ok(());
-        }
-
-        // Only proceed if it’s a GET
-        if !request_line.starts_with("GET") {
-            return Err(std::io::Error::new(
-                std::io::ErrorKind::InvalidData,
-                format!("Invalid HTTP method: {request_line}"),
-            ));
-        }
-
-        // Read headers
-        let mut headers = HashMap::new();
-        let mut line = String::new();
-        loop {
-            line.clear();
-            let bytes = reader.read_line(&mut line)?;
-            if bytes == 0 || line == "\r\n" {
-                break;
-            }
-            if let Some((k, v)) = line.split_once(':') {
-                headers.insert(k.trim().to_lowercase(), v.trim().to_string());
-            }
-        }
-
-        // Check if it's actually a WebSocket upgrade request
-        let is_websocket_upgrade = headers
-            .get("upgrade")
-            .map(|v| v.eq_ignore_ascii_case("websocket"))
-            .unwrap_or(false);
-
-        if !is_websocket_upgrade {
-            // Not a WebSocket request — probably a normal HTTP GET (e.g. health check)
-            let response =
-                "HTTP/1.1 200 OK\r\nContent-Type: text/plain\r\nContent-Length: 2\r\n\r\nOK";
-            stream.write_all(response.as_bytes())?;
-            stream.flush()?;
-            return Ok(());
-        }
-
-        // Validate "Connection: Upgrade"
-        if !headers
-            .get("connection")
-            .map(|v| v.to_lowercase().contains("upgrade"))
-            .unwrap_or(false)
-        {
-            return Err(std::io::Error::new(
-                std::io::ErrorKind::InvalidData,
-                "Missing or invalid Connection header",
-            ));
-        }
-
-        // Validate WebSocket key
-        let key = headers.get("sec-websocket-key").ok_or_else(|| {
-            std::io::Error::new(std::io::ErrorKind::InvalidData, "Missing Sec-WebSocket-Key")
-        })?;
-
-        // Validate version
-        if let Some(ver) = headers.get("sec-websocket-version") {
-            if ver.trim() != "13" {
-                return Err(std::io::Error::new(
-                    std::io::ErrorKind::InvalidData,
-                    format!("Unsupported Sec-WebSocket-Version: {}", ver),
-                ));
-            }
-        }
-
-        // Compute accept key
-        let mut hasher = Sha1::new();
-        hasher.update(key.as_bytes());
-        hasher.update(WS_GUID.as_bytes());
-        let hash = hasher.finalize();
-        let accept_key = Base64.encode(hash);
-
-        // Send response
-        let response = format!(
-            "HTTP/1.1 101 Switching Protocols\r\n\
-             Upgrade: websocket\r\n\
-             Connection: Upgrade\r\n\
-             Sec-WebSocket-Accept: {}\r\n\r\n",
-            accept_key
-        );
-
-        stream.write_all(response.as_bytes())?;
-        stream.flush()?;
-        Ok(())
-    }
-}
-
 pub struct Session(TcpStream, u64);
 
 impl Session {
     /// Create a client
     pub fn new(mut stream: TcpStream) -> crate::Result<Self> {
-        handshake::handle_websocket_handshake(&mut stream)?;
+        crate::handshake::handle_websocket_handshake(&mut stream)?;
         stream.set_read_timeout(Some(std::time::Duration::from_secs(10)))?;
         stream.set_write_timeout(Some(std::time::Duration::from_secs(10)))?;
         Ok(Session(stream, rand::random()))