Timeout in tcpd

This commit is contained in:
Jeremy Soller 2017-04-09 08:36:14 -06:00
parent c4d652b1de
commit 3d683e080a

View file

@ -16,10 +16,25 @@ use std::rc::Rc;
use event::EventQueue;
use netutils::{n16, n32, Ipv4, Ipv4Addr, Ipv4Header, Tcp, TcpHeader, Checksum, TCP_FIN, TCP_SYN, TCP_RST, TCP_PSH, TCP_ACK};
use syscall::data::{Packet, TimeSpec};
use syscall::error::{Error, Result, EACCES, EADDRINUSE, EBADF, EIO, EINVAL, EISCONN, EMSGSIZE, ENOTCONN, EWOULDBLOCK};
use syscall::flag::{EVENT_READ, F_GETFL, F_SETFL, O_ACCMODE, O_CREAT, O_RDWR, O_NONBLOCK};
use syscall::error::{Error, Result, EACCES, EADDRINUSE, EBADF, EIO, EINVAL, EISCONN, EMSGSIZE, ENOTCONN, ETIMEDOUT, EWOULDBLOCK};
use syscall::flag::{CLOCK_MONOTONIC, EVENT_READ, F_GETFL, F_SETFL, O_ACCMODE, O_CREAT, O_RDWR, O_NONBLOCK};
use syscall::scheme::SchemeMut;
fn add_time(a: &TimeSpec, b: &TimeSpec) -> TimeSpec {
let mut secs = a.tv_sec + b.tv_sec;
let mut nsecs = a.tv_nsec + b.tv_nsec;
while nsecs >= 1000000000 {
nsecs -= 1000000000;
secs += 1;
}
TimeSpec {
tv_sec: secs,
tv_nsec: nsecs
}
}
fn parse_socket(socket: &str) -> (Ipv4Addr, u16) {
let mut socket_parts = socket.split(":");
let host = Ipv4Addr::from_str(socket_parts.next().unwrap_or(""));
@ -55,8 +70,8 @@ struct TcpHandle {
ack: u32,
data: VecDeque<(Ipv4, Tcp)>,
todo_dup: VecDeque<Packet>,
todo_read: VecDeque<Packet>,
todo_write: VecDeque<Packet>,
todo_read: VecDeque<(Option<TimeSpec>, Packet)>,
todo_write: VecDeque<(Option<TimeSpec>, Packet)>,
}
impl TcpHandle {
@ -131,6 +146,7 @@ enum Handle {
struct Tcpd {
scheme_file: File,
tcp_file: File,
time_file: File,
ports: BTreeMap<u16, usize>,
next_id: usize,
handles: BTreeMap<usize, Handle>,
@ -138,10 +154,11 @@ struct Tcpd {
}
impl Tcpd {
fn new(scheme_file: File, tcp_file: File) -> Self {
fn new(scheme_file: File, tcp_file: File, time_file: File) -> Self {
Tcpd {
scheme_file: scheme_file,
tcp_file: tcp_file,
time_file: time_file,
ports: BTreeMap::new(),
next_id: 1,
handles: BTreeMap::new(),
@ -156,6 +173,9 @@ impl Tcpd {
break;
}
let mut time = TimeSpec::default();
syscall::clock_gettime(CLOCK_MONOTONIC, &mut time).map_err(|err| io::Error::from_raw_os_error(err.errno))?;
let a = packet.a;
self.handle(&mut packet);
if packet.a == (-EWOULDBLOCK) as usize {
@ -168,11 +188,31 @@ impl Tcpd {
},
syscall::number::SYS_READ => {
packet.a = a;
handle.todo_read.push_back(packet);
let timeout = match handle.read_timeout {
Some(read_timeout) => {
let timeout = add_time(&time, &read_timeout);
self.time_file.write(&timeout)?;
Some(timeout)
},
None => None
};
handle.todo_read.push_back((timeout, packet));
},
syscall::number::SYS_WRITE => {
packet.a = a;
handle.todo_write.push_back(packet);
let timeout = match handle.write_timeout {
Some(write_timeout) => {
let timeout = add_time(&time, &write_timeout);
self.time_file.write(&timeout)?;
Some(timeout)
},
None => None
};
handle.todo_write.push_back((timeout, packet));
},
_ => {
self.scheme_file.write(&packet)?;
@ -271,7 +311,7 @@ impl Tcpd {
}
while ! handle.todo_read.is_empty() && (! handle.data.is_empty() || handle.read_closed()) {
let mut packet = handle.todo_read.pop_front().unwrap();
let (_timeout, mut packet) = handle.todo_read.pop_front().unwrap();
let buf = unsafe { slice::from_raw_parts_mut(packet.c as *mut u8, packet.d) };
if let Some((_ip, tcp)) = handle.data.pop_front() {
let mut i = 0;
@ -288,7 +328,7 @@ impl Tcpd {
}
if ! handle.todo_write.is_empty() && handle.state == State::Established {
let mut packet = handle.todo_write.pop_front().unwrap();
let (_timeout, mut packet) = handle.todo_write.pop_front().unwrap();
let buf = unsafe { slice::from_raw_parts(packet.c as *const u8, packet.d) };
let tcp = handle.create_tcp(TCP_ACK | TCP_PSH, buf.to_vec());
@ -404,6 +444,49 @@ impl Tcpd {
Ok(())
}
fn time_event(&mut self) -> io::Result<()> {
let mut time = TimeSpec::default();
if self.time_file.read(&mut time)? < mem::size_of::<TimeSpec>() {
return Err(io::Error::from_raw_os_error(EINVAL));
}
for (_id, handle) in self.handles.iter_mut() {
if let Handle::Tcp(ref mut handle) = *handle {
let mut i = 0;
while i < handle.todo_read.len() {
if let Some(timeout) = handle.todo_read.get(i).map(|e| e.0.clone()).unwrap_or(None) {
if time.tv_sec > timeout.tv_sec || (time.tv_sec == timeout.tv_sec && time.tv_nsec >= timeout.tv_nsec) {
let (_timeout, mut packet) = handle.todo_read.remove(i).unwrap();
packet.a = (-ETIMEDOUT) as usize;
self.scheme_file.write(&packet)?;
} else {
i += 1;
}
} else {
i += 1;
}
}
let mut i = 0;
while i < handle.todo_write.len() {
if let Some(timeout) = handle.todo_write.get(i).map(|e| e.0.clone()).unwrap_or(None) {
if time.tv_sec > timeout.tv_sec || (time.tv_sec == timeout.tv_sec && time.tv_nsec >= timeout.tv_nsec) {
let (_timeout, mut packet) = handle.todo_write.remove(i).unwrap();
packet.a = (-ETIMEDOUT) as usize;
self.scheme_file.write(&packet)?;
} else {
i += 1;
}
} else {
i += 1;
}
}
}
}
Ok(())
}
}
impl SchemeMut for Tcpd {
@ -785,14 +868,21 @@ impl SchemeMut for Tcpd {
}
}
fn daemon(tcp_fd: usize, scheme_fd: usize) {
let tcp_file = unsafe { File::from_raw_fd(tcp_fd) };
fn daemon(scheme_fd: usize, tcp_fd: usize, time_fd: usize) {
let scheme_file = unsafe { File::from_raw_fd(scheme_fd) };
let tcp_file = unsafe { File::from_raw_fd(tcp_fd) };
let time_file = unsafe { File::from_raw_fd(time_fd) };
let tcpd = Rc::new(RefCell::new(Tcpd::new(scheme_file, tcp_file)));
let tcpd = Rc::new(RefCell::new(Tcpd::new(scheme_file, tcp_file, time_file)));
let mut event_queue = EventQueue::<()>::new().expect("tcpd: failed to create event queue");
let time_tcpd = tcpd.clone();
event_queue.add(time_fd, move |_count: usize| -> io::Result<Option<()>> {
time_tcpd.borrow_mut().time_event()?;
Ok(None)
}).expect("tcpd: failed to listen to events on time:");
let tcp_tcpd = tcpd.clone();
event_queue.add(tcp_fd, move |_count: usize| -> io::Result<Option<()>> {
tcp_tcpd.borrow_mut().tcp_event()?;
@ -810,23 +900,32 @@ fn daemon(tcp_fd: usize, scheme_fd: usize) {
}
fn main() {
match syscall::open("ip:6", O_RDWR | O_NONBLOCK) {
Ok(tcp_fd) => {
// Daemonize
if unsafe { syscall::clone(0).unwrap() } == 0 {
match syscall::open(":tcp", O_RDWR | O_CREAT | O_NONBLOCK) {
Ok(scheme_fd) => {
daemon(tcp_fd, scheme_fd);
},
Err(err) => {
println!("tcpd: failed to create tcp scheme: {}", err);
process::exit(1);
let time_path = format!("time:{}", CLOCK_MONOTONIC);
match syscall::open(&time_path, O_RDWR) {
Ok(time_fd) => {
match syscall::open("ip:6", O_RDWR | O_NONBLOCK) {
Ok(tcp_fd) => {
// Daemonize
if unsafe { syscall::clone(0).unwrap() } == 0 {
match syscall::open(":tcp", O_RDWR | O_CREAT | O_NONBLOCK) {
Ok(scheme_fd) => {
daemon(scheme_fd, tcp_fd, time_fd);
},
Err(err) => {
println!("tcpd: failed to create tcp scheme: {}", err);
process::exit(1);
}
}
}
},
Err(err) => {
println!("tcpd: failed to open ip:6: {}", err);
process::exit(1);
}
}
},
Err(err) => {
println!("tcpd: failed to open ip:6: {}", err);
println!("tcpd: failed to open {}: {}", time_path, err);
process::exit(1);
}
}