Cargo.lock

@@ -111,6 +111,7 @@ dependencies = [
  "criterion",
  "env_logger",
  "exitcode",
+ "httparse",
  "ipnetwork",
  "libc",
  "log",
@@ -289,6 +290,12 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "httparse"
+version = "1.7.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "496ce29bb5a52785b44e0f7ca2847ae0bb839c9bd28f69acac9b99d461c0c04c"
+
 [[package]]
 name = "humantime"
 version = "2.1.0"

Cargo.toml

@@ -25,6 +25,9 @@ tempfile = "3.3"
 [dev-dependencies]
 criterion = "0.3"
 
+# examples/tls
+httparse = "1"
+
 [[bench]]
 name = "clone3"
 harness = false

examples/tls/http.rs

@@ -0,0 +1,61 @@
+use std::fs;
+use std::io::{Read, Write};
+use std::net::TcpStream;
+use std::path::PathBuf;
+
+pub(super) fn handler(mut stream: TcpStream) -> i32 {
+    println!("entered http handler");
+
+    let mut buf = Vec::new();
+    loop {
+        let buf_len = buf.len();
+        buf.resize_with(buf_len + 1024, Default::default);
+
+        if stream.read(&mut buf[buf_len..]).unwrap() == 0 {
+            break;
+        }
+
+        let mut headers = [httparse::EMPTY_HEADER; 64];
+        let mut req = httparse::Request::new(&mut headers);
+        let result = req.parse(&buf).unwrap();
+
+        if result.is_partial() {
+            continue;
+        }
+
+        let filename = if req.method != Some("GET") {
+            None
+        } else {
+            req.path
+        };
+
+        let status_line = if filename.is_some() {
+            "HTTP/1.1 200 OK"
+        } else {
+            "HTTP/1.1 404 NOT FOUND"
+        };
+
+        let contents = if let Some(filename) = filename {
+            fs::read_to_string(
+                PathBuf::from("/var/www/html/")
+                    .join(filename.strip_prefix('/').unwrap_or(filename)),
+            )
+            .unwrap()
+        } else {
+            "content not found\n".to_string()
+        };
+
+        let response_header = format!(
+            "{}\r\nContent-Length: {}\r\n\r\n",
+            status_line,
+            contents.len(),
+        );
+
+        stream.write_all(response_header.as_bytes()).unwrap();
+        stream.write_all(contents.as_bytes()).unwrap();
+
+        break;
+    }
+
+    exitcode::OK
+}

examples/tls/main.rs

@@ -0,0 +1,109 @@
+mod http;
+
+use std::fs::File;
+use std::net::{TcpListener, TcpStream};
+
+fn main() {
+    let mut args = std::env::args();
+
+    let _bin = args.next();
+    let entrypoint = args.next();
+
+    match entrypoint {
+        Some(s) => match s.as_str() {
+            "connection_listener" => connection_listener_entrypoint(),
+            "http_handler" => http_handler_entrypoint(),
+
+            _ => unimplemented!(),
+        },
+        None => unimplemented!(),
+    }
+}
+
+fn connection_listener_entrypoint() {
+    // imports
+    use std::os::unix::io::{FromRawFd, RawFd};
+
+    // argument parsing
+    let mut args = std::env::args();
+
+    let _bin = args.next();
+    let _entrypoint = args.next();
+
+    let http_handler_trigger = args.next();
+    let http_handler_trigger: RawFd = http_handler_trigger
+        .expect("request handler required")
+        .parse()
+        .expect("tcp listener should be a file descriptor");
+    let http_handler_trigger = unsafe { File::from_raw_fd(http_handler_trigger) };
+
+    let tcp_listener = args.next();
+    let tcp_listener: RawFd = tcp_listener
+        .expect("tcp listener required")
+        .parse()
+        .expect("tcp listener should be a file descriptor");
+    let tcp_listener = unsafe { TcpListener::from_raw_fd(tcp_listener) };
+
+    // actual function body
+    fn connection_listener(http_handler_trigger: File, tcp_listener: TcpListener) -> i32 {
+        println!("connection_listener entered");
+
+        // handle incoming connections
+        for stream in tcp_listener.incoming() {
+            let stream = match stream {
+                Ok(s) => s,
+                Err(e) => {
+                    println!("connection listener: error: {}", e);
+                    return 1;
+                }
+            };
+
+            println!("received a new connection");
+            http_handler(&http_handler_trigger, stream);
+        }
+
+        exitcode::OK
+    }
+
+    // run function
+    std::process::exit(connection_listener(http_handler_trigger, tcp_listener));
+}
+
+fn http_handler(trigger_socket: &File, stream: TcpStream) {
+    // imports
+    use nix::sys::socket::{sendmsg, ControlMessage, MsgFlags};
+    use std::os::unix::io::AsRawFd;
+
+    // send file descriptor(s)
+    let sockfd = trigger_socket.as_raw_fd();
+    let fds = [stream.as_raw_fd()];
+
+    sendmsg::<()>(
+        sockfd,
+        &[],
+        &[ControlMessage::ScmRights(&fds)],
+        MsgFlags::empty(),
+        None,
+    )
+    .unwrap();
+}
+
+fn http_handler_entrypoint() {
+    // imports
+    use std::os::unix::io::{FromRawFd, RawFd};
+
+    // argument parsing
+    let mut args = std::env::args();
+
+    let _bin = args.next();
+    let _entrypoint = args.next();
+
+    let stream = args.next();
+    let stream: RawFd = stream
+        .expect("request stream required")
+        .parse()
+        .expect("request stream should be a file descriptor");
+    let stream = unsafe { TcpStream::from_raw_fd(stream) };
+
+    std::process::exit(http::handler(stream));
+}

examples/tls/spec.json

@@ -0,0 +1,76 @@
+{
+    "entrypoints": {
+        "connection_listener": {
+            "args": [
+                "BinaryName",
+                "Entrypoint",
+                {
+                    "FileSocket": {
+                        "Tx": "http"
+                    }
+                },
+                {
+                    "TcpListener": {
+                        "addr": "0.0.0.0:8443"
+                    }
+                }
+            ],
+            "environment": [
+                {
+                    "Filesystem": {
+                        "host_path": "/lib/x86_64-linux-gnu/libgcc_s.so.1",
+                        "environment_path": "/lib/libgcc_s.so.1"
+                    }
+                },
+                {
+                    "Filesystem": {
+                        "host_path": "/lib/x86_64-linux-gnu/libc.so.6",
+                        "environment_path": "/lib/libc.so.6"
+                    }
+                },
+                {
+                    "Filesystem": {
+                        "host_path": "/lib64/ld-linux-x86-64.so.2",
+                        "environment_path": "/lib64/ld-linux-x86-64.so.2"
+                    }
+                }
+            ]
+        },
+        "http_handler": {
+            "trigger": {
+                "FileSocket": "http"
+            },
+            "args": [
+                "BinaryName",
+                "Entrypoint",
+                "Trigger"
+            ],
+            "environment": [
+                {
+                    "Filesystem": {
+                        "host_path": "/var/www/html",
+                        "environment_path": "/var/www/html"
+                    }
+                },
+                {
+                    "Filesystem": {
+                        "host_path": "/lib/x86_64-linux-gnu/libgcc_s.so.1",
+                        "environment_path": "/lib/libgcc_s.so.1"
+                    }
+                },
+                {
+                    "Filesystem": {
+                        "host_path": "/lib/x86_64-linux-gnu/libc.so.6",
+                        "environment_path": "/lib/libc.so.6"
+                    }
+                },
+                {
+                    "Filesystem": {
+                        "host_path": "/lib64/ld-linux-x86-64.so.2",
+                        "environment_path": "/lib64/ld-linux-x86-64.so.2"
+                    }
+                }
+            ]
+        }
+    }
+}

src/void.rs

@@ -135,14 +135,6 @@ impl VoidBuilder {
         }
 
         debug!("cloned child: {}", child);
-
-        // Leak the child function's resources in the parent process.
-        // This avoids closing files that have been "moved" into the child.
-        // It is also an over-approximation, and may cause actual memory leaks.
-        // As the spawning process is normally short lived, this shouldn't
-        // be a problem.
-        std::mem::forget(child_fn);
-
         Ok(VoidHandle { pid: child })
     }