net: move tuntap from std example to separate crate. (#1737)

examples/std/Cargo.toml

@@ -9,7 +9,7 @@ embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["lo
 embassy-executor = { version = "0.2.0", path = "../../embassy-executor", features = ["arch-std", "executor-thread", "log", "nightly", "integrated-timers"] }
 embassy-time = { version = "0.1.2", path = "../../embassy-time", features = ["log", "std", "nightly"] }
 embassy-net = { version = "0.1.0", path = "../../embassy-net", features=[ "std", "nightly", "log", "medium-ethernet", "tcp", "udp", "dns", "dhcpv4", "unstable-traits", "proto-ipv6"] }
-embassy-net-driver = { version = "0.1.0", path = "../../embassy-net-driver" }
+embassy-net-tuntap = { version = "0.1.0", path = "../../embassy-net-tuntap" }
 embedded-io = { version = "0.4.0", features = ["async", "std", "futures"] }
 critical-section = { version = "1.1", features = ["std"] }
 
@@ -18,7 +18,6 @@ env_logger = "0.9.0"
 futures = { version = "0.3.17" }
 log = "0.4.14"
 nix = "0.26.2"
-libc = "0.2.101"
 clap = { version = "3.0.0-beta.5", features = ["derive"] }
 rand_core = { version = "0.6.3", features = ["std"] }
 heapless = { version = "0.7.5", default-features = false }

examples/std/src/bin/net.rs

@@ -6,6 +6,7 @@ use clap::Parser;
 use embassy_executor::{Executor, Spawner};
 use embassy_net::tcp::TcpSocket;
 use embassy_net::{Config, Ipv4Address, Ipv4Cidr, Stack, StackResources};
+use embassy_net_tuntap::TunTapDevice;
 use embassy_time::Duration;
 use embedded_io::asynch::Write;
 use heapless::Vec;
@@ -13,10 +14,6 @@ use log::*;
 use rand_core::{OsRng, RngCore};
 use static_cell::{make_static, StaticCell};
 
-#[path = "../tuntap.rs"]
-mod tuntap;
-
-use crate::tuntap::TunTapDevice;
 #[derive(Parser)]
 #[clap(version = "1.0")]
 struct Opts {

examples/std/src/bin/net_dns.rs

@@ -6,15 +6,12 @@ use clap::Parser;
 use embassy_executor::{Executor, Spawner};
 use embassy_net::dns::DnsQueryType;
 use embassy_net::{Config, Ipv4Address, Ipv4Cidr, Stack, StackResources};
+use embassy_net_tuntap::TunTapDevice;
 use heapless::Vec;
 use log::*;
 use rand_core::{OsRng, RngCore};
 use static_cell::{make_static, StaticCell};
 
-#[path = "../tuntap.rs"]
-mod tuntap;
-
-use crate::tuntap::TunTapDevice;
 #[derive(Parser)]
 #[clap(version = "1.0")]
 struct Opts {

examples/std/src/bin/net_udp.rs

@@ -4,15 +4,12 @@ use clap::Parser;
 use embassy_executor::{Executor, Spawner};
 use embassy_net::udp::{PacketMetadata, UdpSocket};
 use embassy_net::{Config, Ipv4Address, Ipv4Cidr, Stack, StackResources};
+use embassy_net_tuntap::TunTapDevice;
 use heapless::Vec;
 use log::*;
 use rand_core::{OsRng, RngCore};
 use static_cell::{make_static, StaticCell};
 
-#[path = "../tuntap.rs"]
-mod tuntap;
-
-use crate::tuntap::TunTapDevice;
 #[derive(Parser)]
 #[clap(version = "1.0")]
 struct Opts {

examples/std/src/bin/tcp_accept.rs

@@ -7,6 +7,7 @@ use clap::Parser;
 use embassy_executor::{Executor, Spawner};
 use embassy_net::tcp::TcpSocket;
 use embassy_net::{Config, Ipv4Address, Ipv4Cidr, Stack, StackResources};
+use embassy_net_tuntap::TunTapDevice;
 use embassy_time::{Duration, Timer};
 use embedded_io::asynch::Write as _;
 use heapless::Vec;
@@ -14,10 +15,6 @@ use log::*;
 use rand_core::{OsRng, RngCore};
 use static_cell::{make_static, StaticCell};
 
-#[path = "../tuntap.rs"]
-mod tuntap;
-
-use crate::tuntap::TunTapDevice;
 #[derive(Parser)]
 #[clap(version = "1.0")]
 struct Opts {

examples/std/src/tuntap.rs

@@ -1,224 +0,0 @@
-use std::io;
-use std::io::{Read, Write};
-use std::os::unix::io::{AsRawFd, RawFd};
-use std::task::Context;
-
-use async_io::Async;
-use embassy_net_driver::{self, Capabilities, Driver, HardwareAddress, LinkState};
-use log::*;
-
-pub const SIOCGIFMTU: libc::c_ulong = 0x8921;
-pub const _SIOCGIFINDEX: libc::c_ulong = 0x8933;
-pub const _ETH_P_ALL: libc::c_short = 0x0003;
-pub const TUNSETIFF: libc::c_ulong = 0x400454CA;
-pub const _IFF_TUN: libc::c_int = 0x0001;
-pub const IFF_TAP: libc::c_int = 0x0002;
-pub const IFF_NO_PI: libc::c_int = 0x1000;
-
-const ETHERNET_HEADER_LEN: usize = 14;
-
-#[repr(C)]
-#[derive(Debug)]
-struct ifreq {
-    ifr_name: [libc::c_char; libc::IF_NAMESIZE],
-    ifr_data: libc::c_int, /* ifr_ifindex or ifr_mtu */
-}
-
-fn ifreq_for(name: &str) -> ifreq {
-    let mut ifreq = ifreq {
-        ifr_name: [0; libc::IF_NAMESIZE],
-        ifr_data: 0,
-    };
-    for (i, byte) in name.as_bytes().iter().enumerate() {
-        ifreq.ifr_name[i] = *byte as libc::c_char
-    }
-    ifreq
-}
-
-fn ifreq_ioctl(lower: libc::c_int, ifreq: &mut ifreq, cmd: libc::c_ulong) -> io::Result<libc::c_int> {
-    unsafe {
-        let res = libc::ioctl(lower, cmd as _, ifreq as *mut ifreq);
-        if res == -1 {
-            return Err(io::Error::last_os_error());
-        }
-    }
-
-    Ok(ifreq.ifr_data)
-}
-
-#[derive(Debug)]
-pub struct TunTap {
-    fd: libc::c_int,
-    mtu: usize,
-}
-
-impl AsRawFd for TunTap {
-    fn as_raw_fd(&self) -> RawFd {
-        self.fd
-    }
-}
-
-impl TunTap {
-    pub fn new(name: &str) -> io::Result<TunTap> {
-        unsafe {
-            let fd = libc::open(
-                "/dev/net/tun\0".as_ptr() as *const libc::c_char,
-                libc::O_RDWR | libc::O_NONBLOCK,
-            );
-            if fd == -1 {
-                return Err(io::Error::last_os_error());
-            }
-
-            let mut ifreq = ifreq_for(name);
-            ifreq.ifr_data = IFF_TAP | IFF_NO_PI;
-            ifreq_ioctl(fd, &mut ifreq, TUNSETIFF)?;
-
-            let socket = libc::socket(libc::AF_INET, libc::SOCK_DGRAM, libc::IPPROTO_IP);
-            if socket == -1 {
-                return Err(io::Error::last_os_error());
-            }
-
-            let ip_mtu = ifreq_ioctl(socket, &mut ifreq, SIOCGIFMTU);
-            libc::close(socket);
-            let ip_mtu = ip_mtu? as usize;
-
-            // SIOCGIFMTU returns the IP MTU (typically 1500 bytes.)
-            // smoltcp counts the entire Ethernet packet in the MTU, so add the Ethernet header size to it.
-            let mtu = ip_mtu + ETHERNET_HEADER_LEN;
-
-            Ok(TunTap { fd, mtu })
-        }
-    }
-}
-
-impl Drop for TunTap {
-    fn drop(&mut self) {
-        unsafe {
-            libc::close(self.fd);
-        }
-    }
-}
-
-impl io::Read for TunTap {
-    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
-        let len = unsafe { libc::read(self.fd, buf.as_mut_ptr() as *mut libc::c_void, buf.len()) };
-        if len == -1 {
-            Err(io::Error::last_os_error())
-        } else {
-            Ok(len as usize)
-        }
-    }
-}
-
-impl io::Write for TunTap {
-    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
-        let len = unsafe { libc::write(self.fd, buf.as_ptr() as *mut libc::c_void, buf.len()) };
-        if len == -1 {
-            Err(io::Error::last_os_error())
-        } else {
-            Ok(len as usize)
-        }
-    }
-
-    fn flush(&mut self) -> io::Result<()> {
-        Ok(())
-    }
-}
-
-pub struct TunTapDevice {
-    device: Async<TunTap>,
-}
-
-impl TunTapDevice {
-    pub fn new(name: &str) -> io::Result<TunTapDevice> {
-        Ok(Self {
-            device: Async::new(TunTap::new(name)?)?,
-        })
-    }
-}
-
-impl Driver for TunTapDevice {
-    type RxToken<'a> = RxToken where Self: 'a;
-    type TxToken<'a> = TxToken<'a> where Self: 'a;
-
-    fn receive(&mut self, cx: &mut Context) -> Option<(Self::RxToken<'_>, Self::TxToken<'_>)> {
-        let mut buf = vec![0; self.device.get_ref().mtu];
-        loop {
-            match self.device.get_mut().read(&mut buf) {
-                Ok(n) => {
-                    buf.truncate(n);
-                    return Some((
-                        RxToken { buffer: buf },
-                        TxToken {
-                            device: &mut self.device,
-                        },
-                    ));
-                }
-                Err(e) if e.kind() == io::ErrorKind::WouldBlock => {
-                    if !self.device.poll_readable(cx).is_ready() {
-                        return None;
-                    }
-                }
-                Err(e) => panic!("read error: {:?}", e),
-            }
-        }
-    }
-
-    fn transmit(&mut self, _cx: &mut Context) -> Option<Self::TxToken<'_>> {
-        Some(TxToken {
-            device: &mut self.device,
-        })
-    }
-
-    fn capabilities(&self) -> Capabilities {
-        let mut caps = Capabilities::default();
-        caps.max_transmission_unit = self.device.get_ref().mtu;
-        caps
-    }
-
-    fn link_state(&mut self, _cx: &mut Context) -> LinkState {
-        LinkState::Up
-    }
-
-    fn hardware_address(&self) -> HardwareAddress {
-        HardwareAddress::Ethernet([0x02, 0x03, 0x04, 0x05, 0x06, 0x07])
-    }
-}
-
-#[doc(hidden)]
-pub struct RxToken {
-    buffer: Vec<u8>,
-}
-
-impl embassy_net_driver::RxToken for RxToken {
-    fn consume<R, F>(mut self, f: F) -> R
-    where
-        F: FnOnce(&mut [u8]) -> R,
-    {
-        f(&mut self.buffer)
-    }
-}
-
-#[doc(hidden)]
-pub struct TxToken<'a> {
-    device: &'a mut Async<TunTap>,
-}
-
-impl<'a> embassy_net_driver::TxToken for TxToken<'a> {
-    fn consume<R, F>(self, len: usize, f: F) -> R
-    where
-        F: FnOnce(&mut [u8]) -> R,
-    {
-        let mut buffer = vec![0; len];
-        let result = f(&mut buffer);
-
-        // todo handle WouldBlock with async
-        match self.device.get_mut().write(&buffer) {
-            Ok(_) => {}
-            Err(e) if e.kind() == io::ErrorKind::WouldBlock => info!("transmit WouldBlock"),
-            Err(e) => panic!("transmit error: {:?}", e),
-        }
-
-        result
-    }
-}