1 files changed, 302 insertions, 5 deletions

diff --git a/embassy-net/src/lib.rs b/embassy-net/src/lib.rs
index e18e819cb..afe0d6da0 100644
--- a/embassy-net/src/lib.rs
+++ b/embassy-net/src/lib.rs
@@ -9,16 +9,28 @@
 pub(crate) mod fmt;
 
 pub mod device;
-mod stack;
-
-pub use stack::{Config, ConfigStrategy, Stack, StackResources};
-
 #[cfg(feature = "tcp")]
 pub mod tcp;
-
 #[cfg(feature = "udp")]
 pub mod udp;
 
+use core::cell::RefCell;
+use core::future::{poll_fn, Future};
+use core::task::{Context, Poll};
+
+use embassy_sync::waitqueue::WakerRegistration;
+use embassy_time::{Instant, Timer};
+use futures::pin_mut;
+use heapless::Vec;
+#[cfg(feature = "dhcpv4")]
+use smoltcp::iface::SocketHandle;
+use smoltcp::iface::{Interface, InterfaceBuilder, SocketSet, SocketStorage};
+#[cfg(feature = "medium-ethernet")]
+use smoltcp::iface::{Neighbor, NeighborCache, Route, Routes};
+#[cfg(feature = "medium-ethernet")]
+use smoltcp::phy::Medium;
+#[cfg(feature = "dhcpv4")]
+use smoltcp::socket::dhcpv4;
 // smoltcp reexports
 pub use smoltcp::time::{Duration as SmolDuration, Instant as SmolInstant};
 #[cfg(feature = "medium-ethernet")]
@@ -28,3 +40,288 @@ pub use smoltcp::wire::{IpAddress, IpCidr, Ipv4Address, Ipv4Cidr};
 pub use smoltcp::wire::{Ipv6Address, Ipv6Cidr};
 #[cfg(feature = "udp")]
 pub use smoltcp::{socket::udp::PacketMetadata, wire::IpListenEndpoint};
+
+use crate::device::{Device, DeviceAdapter, LinkState};
+
+const LOCAL_PORT_MIN: u16 = 1025;
+const LOCAL_PORT_MAX: u16 = 65535;
+
+pub struct StackResources<const ADDR: usize, const SOCK: usize, const NEIGHBOR: usize> {
+    addresses: [IpCidr; ADDR],
+    sockets: [SocketStorage<'static>; SOCK],
+
+    #[cfg(feature = "medium-ethernet")]
+    routes: [Option<(IpCidr, Route)>; 1],
+    #[cfg(feature = "medium-ethernet")]
+    neighbor_cache: [Option<(IpAddress, Neighbor)>; NEIGHBOR],
+}
+
+impl<const ADDR: usize, const SOCK: usize, const NEIGHBOR: usize> StackResources<ADDR, SOCK, NEIGHBOR> {
+    pub fn new() -> Self {
+        Self {
+            addresses: [IpCidr::new(Ipv4Address::UNSPECIFIED.into(), 32); ADDR],
+            sockets: [SocketStorage::EMPTY; SOCK],
+            #[cfg(feature = "medium-ethernet")]
+            routes: [None; 1],
+            #[cfg(feature = "medium-ethernet")]
+            neighbor_cache: [None; NEIGHBOR],
+        }
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct Config {
+    pub address: Ipv4Cidr,
+    pub gateway: Option<Ipv4Address>,
+    pub dns_servers: Vec<Ipv4Address, 3>,
+}
+
+pub enum ConfigStrategy {
+    Static(Config),
+    #[cfg(feature = "dhcpv4")]
+    Dhcp,
+}
+
+pub struct Stack<D: Device> {
+    pub(crate) socket: RefCell<SocketStack>,
+    inner: RefCell<Inner<D>>,
+}
+
+struct Inner<D: Device> {
+    device: D,
+    link_up: bool,
+    config: Option<Config>,
+    #[cfg(feature = "dhcpv4")]
+    dhcp_socket: Option<SocketHandle>,
+}
+
+pub(crate) struct SocketStack {
+    pub(crate) sockets: SocketSet<'static>,
+    pub(crate) iface: Interface<'static>,
+    pub(crate) waker: WakerRegistration,
+    next_local_port: u16,
+}
+
+impl<D: Device + 'static> Stack<D> {
+    pub fn new<const ADDR: usize, const SOCK: usize, const NEIGH: usize>(
+        mut device: D,
+        config: ConfigStrategy,
+        resources: &'static mut StackResources<ADDR, SOCK, NEIGH>,
+        random_seed: u64,
+    ) -> Self {
+        #[cfg(feature = "medium-ethernet")]
+        let medium = device.capabilities().medium;
+
+        #[cfg(feature = "medium-ethernet")]
+        let ethernet_addr = if medium == Medium::Ethernet {
+            device.ethernet_address()
+        } else {
+            [0, 0, 0, 0, 0, 0]
+        };
+
+        let mut b = InterfaceBuilder::new();
+        b = b.ip_addrs(&mut resources.addresses[..]);
+        b = b.random_seed(random_seed);
+
+        #[cfg(feature = "medium-ethernet")]
+        if medium == Medium::Ethernet {
+            b = b.hardware_addr(HardwareAddress::Ethernet(EthernetAddress(ethernet_addr)));
+            b = b.neighbor_cache(NeighborCache::new(&mut resources.neighbor_cache[..]));
+            b = b.routes(Routes::new(&mut resources.routes[..]));
+        }
+
+        let iface = b.finalize(&mut DeviceAdapter {
+            inner: &mut device,
+            cx: None,
+        });
+
+        let sockets = SocketSet::new(&mut resources.sockets[..]);
+
+        let next_local_port = (random_seed % (LOCAL_PORT_MAX - LOCAL_PORT_MIN) as u64) as u16 + LOCAL_PORT_MIN;
+
+        let mut inner = Inner {
+            device,
+            link_up: false,
+            config: None,
+            #[cfg(feature = "dhcpv4")]
+            dhcp_socket: None,
+        };
+        let mut socket = SocketStack {
+            sockets,
+            iface,
+            waker: WakerRegistration::new(),
+            next_local_port,
+        };
+
+        match config {
+            ConfigStrategy::Static(config) => inner.apply_config(&mut socket, config),
+            #[cfg(feature = "dhcpv4")]
+            ConfigStrategy::Dhcp => {
+                let handle = socket.sockets.add(smoltcp::socket::dhcpv4::Socket::new());
+                inner.dhcp_socket = Some(handle);
+            }
+        }
+
+        Self {
+            socket: RefCell::new(socket),
+            inner: RefCell::new(inner),
+        }
+    }
+
+    fn with<R>(&self, f: impl FnOnce(&SocketStack, &Inner<D>) -> R) -> R {
+        f(&*self.socket.borrow(), &*self.inner.borrow())
+    }
+
+    fn with_mut<R>(&self, f: impl FnOnce(&mut SocketStack, &mut Inner<D>) -> R) -> R {
+        f(&mut *self.socket.borrow_mut(), &mut *self.inner.borrow_mut())
+    }
+
+    pub fn ethernet_address(&self) -> [u8; 6] {
+        self.with(|_s, i| i.device.ethernet_address())
+    }
+
+    pub fn is_link_up(&self) -> bool {
+        self.with(|_s, i| i.link_up)
+    }
+
+    pub fn is_config_up(&self) -> bool {
+        self.with(|_s, i| i.config.is_some())
+    }
+
+    pub fn config(&self) -> Option<Config> {
+        self.with(|_s, i| i.config.clone())
+    }
+
+    pub async fn run(&self) -> ! {
+        poll_fn(|cx| {
+            self.with_mut(|s, i| i.poll(cx, s));
+            Poll::<()>::Pending
+        })
+        .await;
+        unreachable!()
+    }
+}
+
+impl SocketStack {
+    #[allow(clippy::absurd_extreme_comparisons)]
+    pub fn get_local_port(&mut self) -> u16 {
+        let res = self.next_local_port;
+        self.next_local_port = if res >= LOCAL_PORT_MAX { LOCAL_PORT_MIN } else { res + 1 };
+        res
+    }
+}
+
+impl<D: Device + 'static> Inner<D> {
+    fn apply_config(&mut self, s: &mut SocketStack, config: Config) {
+        #[cfg(feature = "medium-ethernet")]
+        let medium = self.device.capabilities().medium;
+
+        debug!("Acquired IP configuration:");
+
+        debug!("   IP address:      {}", config.address);
+        self.set_ipv4_addr(s, config.address);
+
+        #[cfg(feature = "medium-ethernet")]
+        if medium == Medium::Ethernet {
+            if let Some(gateway) = config.gateway {
+                debug!("   Default gateway: {}", gateway);
+                s.iface.routes_mut().add_default_ipv4_route(gateway).unwrap();
+            } else {
+                debug!("   Default gateway: None");
+                s.iface.routes_mut().remove_default_ipv4_route();
+            }
+        }
+        for (i, s) in config.dns_servers.iter().enumerate() {
+            debug!("   DNS server {}:    {}", i, s);
+        }
+
+        self.config = Some(config)
+    }
+
+    #[allow(unused)] // used only with dhcp
+    fn unapply_config(&mut self, s: &mut SocketStack) {
+        #[cfg(feature = "medium-ethernet")]
+        let medium = self.device.capabilities().medium;
+
+        debug!("Lost IP configuration");
+        self.set_ipv4_addr(s, Ipv4Cidr::new(Ipv4Address::UNSPECIFIED, 0));
+        #[cfg(feature = "medium-ethernet")]
+        if medium == Medium::Ethernet {
+            s.iface.routes_mut().remove_default_ipv4_route();
+        }
+        self.config = None
+    }
+
+    fn set_ipv4_addr(&mut self, s: &mut SocketStack, cidr: Ipv4Cidr) {
+        s.iface.update_ip_addrs(|addrs| {
+            let dest = addrs.iter_mut().next().unwrap();
+            *dest = IpCidr::Ipv4(cidr);
+        });
+    }
+
+    fn poll(&mut self, cx: &mut Context<'_>, s: &mut SocketStack) {
+        s.waker.register(cx.waker());
+
+        let timestamp = instant_to_smoltcp(Instant::now());
+        let mut smoldev = DeviceAdapter {
+            cx: Some(cx),
+            inner: &mut self.device,
+        };
+        if s.iface.poll(timestamp, &mut smoldev, &mut s.sockets).is_err() {
+            // If poll() returns error, it may not be done yet, so poll again later.
+            cx.waker().wake_by_ref();
+            return;
+        }
+
+        // Update link up
+        let old_link_up = self.link_up;
+        self.link_up = self.device.link_state(cx) == LinkState::Up;
+
+        // Print when changed
+        if old_link_up != self.link_up {
+            info!("link_up = {:?}", self.link_up);
+        }
+
+        #[cfg(feature = "dhcpv4")]
+        if let Some(dhcp_handle) = self.dhcp_socket {
+            let socket = s.sockets.get_mut::<dhcpv4::Socket>(dhcp_handle);
+
+            if self.link_up {
+                match socket.poll() {
+                    None => {}
+                    Some(dhcpv4::Event::Deconfigured) => self.unapply_config(s),
+                    Some(dhcpv4::Event::Configured(config)) => {
+                        let config = Config {
+                            address: config.address,
+                            gateway: config.router,
+                            dns_servers: config.dns_servers,
+                        };
+                        self.apply_config(s, config)
+                    }
+                }
+            } else if old_link_up {
+                socket.reset();
+                self.unapply_config(s);
+            }
+        }
+        //if old_link_up || self.link_up {
+        //    self.poll_configurator(timestamp)
+        //}
+
+        if let Some(poll_at) = s.iface.poll_at(timestamp, &mut s.sockets) {
+            let t = Timer::at(instant_from_smoltcp(poll_at));
+            pin_mut!(t);
+            if t.poll(cx).is_ready() {
+                cx.waker().wake_by_ref();
+            }
+        }
+    }
+}
+
+fn instant_to_smoltcp(instant: Instant) -> SmolInstant {
+    SmolInstant::from_millis(instant.as_millis() as i64)
+}
+
+fn instant_from_smoltcp(instant: SmolInstant) -> Instant {
+    Instant::from_millis(instant.total_millis() as u64)
+}