Add TCP-based NAL implementation (#24)

* Adding TCP-based NAL implementation

* Updating NAL dependency

* Updating connect to handle network errors

* Adding support for getting IP and MAC, allowing transparent access to the W5500 in the interface.

* Fixing TCP connect when not in INIT

* Adding wait after reset

* Reverting changes

* More delta reductions

* Fixing format

* Updating changelog

* Fixing docs

* Updating NAL version

* Adding debug derive

* fixing TCP write

* Updating RX receive size to allow less than 8 bytes

* Fixing clippy lints

CHANGELOG.md

@@ -1,3 +1,8 @@
+# Unreleased
+
+### Added
+- Added TCP client support
+
 # 0.3.0 (June 10, 2020)
 
 ### Breaking changes

Cargo.toml

@@ -1,9 +1,9 @@
 [package]
 name = "w5500"
 version = "0.3.0"
-authors = ["Michael Watzko <michael@watzko.de>", "Jonah Dahlquist <hi@jonah.name>"]
+authors = ["Michael Watzko <michael@watzko.de>", "Jonah Dahlquist <hi@jonah.name>", "Ryan Summers <ryan.summers@vertigo-designs.com"]
 repository = "https://github.com/kellerkindt/w5500.git"
-description = "W5500 IoT Controller implementation. Currently UDP sending and receiving is working. WIP"
+description = "W5500 IoT Controller implementation."
 keywords = ["embedded", "w5500", "iot", "arm", "embedded-hal-driver"]
 categories = ["embedded", "hardware-support", "no-std", "network-programming"]
 license = "MIT OR Apache-2.0"
@@ -13,9 +13,10 @@ edition = "2018"
 [dependencies]
 byteorder = { version = "1.3.4", default-features = false }
 embedded-hal = "0.2.4"
-embedded-nal = "0.4.0"
+embedded-nal = "0.6.0"
 bit_field = "0.10.1"
+derive-try-from-primitive = "1"
 nb = "1.0.0"
 
 [features]
-no-chip-version-assertion = []
+no-chip-version-assertion = []

README.md

@@ -77,5 +77,5 @@ Usage of borrowed SPI-Bus and previously initialized `Device`:
 
 In no particular order, things to do to improve this driver.
 
-* Add support for TCP
+* Add support for TCP server implementations
 * Add support for DHCP

src/lib.rs

@@ -1,6 +1,6 @@
 #![no_std]
 #![allow(unused)]
-#![deny(broken_intra_doc_links)]
+#![deny(rustdoc::broken_intra_doc_links)]
 
 pub mod bus;
 mod device;
@@ -8,6 +8,7 @@ mod host;
 pub mod net;
 pub mod register;
 mod socket;
+pub mod tcp;
 pub mod udp;
 mod uninitialized_device;
 
@@ -34,8 +35,8 @@ pub enum OnPingRequest {
     Ignore = 0b00010000,
 }
 
-/// Use [TransmissionMode::PPoE] when talking
+/// Use [ConnectionType::PPoE] when talking
-/// to an ADSL modem. Otherwise use [TransmissionMode::Ethernet]
+/// to an ADSL modem. Otherwise use [ConnectionType::Ethernet]
 #[repr(u8)]
 #[derive(Copy, Clone, PartialOrd, PartialEq)]
 pub enum ConnectionType {

src/register.rs

@@ -159,19 +159,25 @@ pub const SOCKET7_BUFFER_TX: u8 = 0b000_11110;
 pub const SOCKET7_BUFFER_RX: u8 = 0b000_11111;
 
 pub mod socketn {
+    use derive_try_from_primitive::TryFromPrimitive;
+
     pub const MODE: u16 = 0x00;
     #[repr(u8)]
     pub enum Protocol {
-        Udp = 0b10u8,
+        Closed = 0b00,
-        Closed = 0u8,
+        Tcp = 0b01,
+        Udp = 0b10,
     }
     pub const COMMAND: u16 = 0x01;
     #[repr(u8)]
     pub enum Command {
         Open = 0x01,
+        Listen = 0x02,
+        Connect = 0x04,
+        Discon = 0x08,
+        Close = 0x10,
         Send = 0x20,
         Receive = 0x40,
-        Close = 0x10,
     }
 
     pub const INTERRUPT: u16 = 0x02;
@@ -183,12 +189,35 @@ pub mod socketn {
         Receive = 0b00100u8,
     }
 
+    pub const STATUS: u16 = 0x03;
+    #[repr(u8)]
+    #[derive(TryFromPrimitive)]
+    pub enum Status {
+        Closed = 0x00,
+        Init = 0x13,
+        Listen = 0x14,
+        Established = 0x17,
+        CloseWait = 0x1c,
+        Udp = 0x22,
+        MacRaw = 0x42,
+
+        // Transient states.
+        SynSent = 0x15,
+        SynRecv = 0x16,
+        FinWait = 0x18,
+        Closing = 0x1a,
+        TimeWait = 0x1b,
+        LastAck = 0x1d,
+    }
+
     pub const SOURCE_PORT: u16 = 0x04;
 
     pub const DESTINATION_IP: u16 = 0x0C;
 
     pub const DESTINATION_PORT: u16 = 0x10;
 
+    pub const TX_FREE_SIZE: u16 = 0x20;
+
     pub const TX_DATA_READ_POINTER: u16 = 0x22;
 
     pub const TX_DATA_WRITE_POINTER: u16 = 0x24;

src/socket.rs

@@ -50,6 +50,12 @@ impl Socket {
         Ok(())
     }
 
+    pub fn get_status<SpiBus: Bus>(&self, bus: &mut SpiBus) -> Result<u8, SpiBus::Error> {
+        let mut data = [0u8];
+        bus.read_frame(self.register(), socketn::STATUS, &mut data)?;
+        Ok(data[0])
+    }
+
     pub fn reset_interrupt<SpiBus: Bus>(
         &self,
         bus: &mut SpiBus,
@@ -178,9 +184,15 @@ impl Socket {
             bus.read_frame(self.register(), socketn::RECEIVED_SIZE, &mut sample_0)?;
             let mut sample_1 = [0u8; 2];
             bus.read_frame(self.register(), socketn::RECEIVED_SIZE, &mut sample_1)?;
-            if sample_0 == sample_1 && sample_0[0] >= 8 {
+            if sample_0 == sample_1 {
                 break Ok(u16::from_be_bytes(sample_0));
             }
         }
     }
+
+    pub fn get_tx_free_size<SpiBus: Bus>(&self, bus: &mut SpiBus) -> Result<u16, SpiBus::Error> {
+        let mut data = [0; 2];
+        bus.read_frame(self.register(), socketn::TX_FREE_SIZE, &mut data)?;
+        Ok(u16::from_be_bytes(data))
+    }
 }

src/tcp.rs

@@ -0,0 +1,300 @@
+use crate::{
+    bus::Bus,
+    device::{Device, DeviceRefMut},
+    host::Host,
+    register::socketn,
+    socket::Socket,
+};
+
+use embedded_nal::{nb, IpAddr, Ipv4Addr, SocketAddr, SocketAddrV4, TcpClientStack};
+
+use core::convert::TryFrom;
+
+#[derive(Debug)]
+pub enum TcpSocketError<E: core::fmt::Debug> {
+    NoMoreSockets,
+    NotReady,
+    UnsupportedAddress,
+    Other(E),
+    UnsupportedMode,
+}
+
+impl<E: core::fmt::Debug> From<E> for TcpSocketError<E> {
+    fn from(e: E) -> Self {
+        TcpSocketError::Other(e)
+    }
+}
+
+pub struct TcpSocket {
+    socket: Socket,
+}
+
+impl TcpSocket {
+    fn reopen<B: Bus>(&mut self, bus: &mut B) -> Result<(), TcpSocketError<B::Error>> {
+        self.socket.command(bus, socketn::Command::Close)?;
+        self.socket.reset_interrupt(bus, socketn::Interrupt::All)?;
+        self.socket.set_mode(bus, socketn::Protocol::Tcp)?;
+
+        self.socket.set_interrupt_mask(
+            bus,
+            socketn::Interrupt::SendOk as u8 & socketn::Interrupt::Timeout as u8,
+        )?;
+
+        self.socket.command(bus, socketn::Command::Open)?;
+        Ok(())
+    }
+    fn open<B: Bus>(
+        &mut self,
+        bus: &mut B,
+        local_port: u16,
+    ) -> Result<(), TcpSocketError<B::Error>> {
+        self.socket.command(bus, socketn::Command::Close)?;
+        self.socket.reset_interrupt(bus, socketn::Interrupt::All)?;
+        self.socket.set_source_port(bus, local_port)?;
+        self.socket.set_mode(bus, socketn::Protocol::Tcp)?;
+
+        self.socket.set_interrupt_mask(
+            bus,
+            socketn::Interrupt::SendOk as u8 & socketn::Interrupt::Timeout as u8,
+        )?;
+
+        self.socket.command(bus, socketn::Command::Open)?;
+        Ok(())
+    }
+
+    fn close<B: Bus>(&self, bus: &mut B) -> Result<(), TcpSocketError<B::Error>> {
+        self.socket.set_mode(bus, socketn::Protocol::Closed)?;
+        self.socket.command(bus, socketn::Command::Close)?;
+        Ok(())
+    }
+
+    fn connect<B: Bus>(
+        &mut self,
+        bus: &mut B,
+        remote: SocketAddrV4,
+    ) -> Result<(), TcpSocketError<B::Error>> {
+        // Ensure the socket is open and ready before we attempt to connect it.
+        match socketn::Status::try_from(self.socket.get_status(bus)?) {
+            // Happy case: Nothing to do.
+            Ok(socketn::Status::Init) => {}
+
+            // If the socket is in the wrong mode, we can't use it. The user needs to re-open it.
+            Err(_) | Ok(socketn::Status::MacRaw) | Ok(socketn::Status::Udp) => {
+                return Err(TcpSocketError::UnsupportedMode)
+            }
+
+            // All other cases are transient TCP states. For these, we need to reset the TCP
+            // machinery to return to the INIT state.
+            Ok(_) => {
+                self.close(bus)?;
+                self.reopen(bus)?;
+            }
+        }
+
+        // Write the remote port and IP
+        self.socket.set_destination_ip(bus, *remote.ip())?;
+        self.socket.set_destination_port(bus, remote.port())?;
+
+        // Connect the socket.
+        self.socket.command(bus, socketn::Command::Connect)?;
+
+        // Wait for the socket to connect or encounter an error.
+        loop {
+            match socketn::Status::try_from(self.socket.get_status(bus)?) {
+                Ok(socketn::Status::Established) => return Ok(()),
+
+                // The socket is closed if a timeout (ARP or SYN-ACK) or if the TCP socket receives
+                // a RST packet. In this case, the client will need to re-attempt to connect.
+
+                // TODO: Due to limitations of the embedded-nal, we currently still return the
+                // socket (since we cannot inform the user of the connection failure). The returned
+                // socket will not actually be connected.
+                Ok(socketn::Status::Closed) => {
+                    // For now, always return an open socket so that the user can re-connect with
+                    // it in the future.
+                    self.close(bus)?;
+                    return self.reopen(bus);
+                }
+
+                // The socket is still in some transient state. Wait for it to connect or for the
+                // connection to fail.
+                _ => {}
+            }
+        }
+    }
+
+    pub fn is_connected<B: Bus>(&self, bus: &mut B) -> Result<bool, TcpSocketError<B::Error>> {
+        Ok(self.socket.get_status(bus)? == socketn::Status::Established as u8)
+    }
+
+    fn send<B: Bus>(
+        &mut self,
+        bus: &mut B,
+        data: &[u8],
+    ) -> Result<usize, TcpSocketError<B::Error>> {
+        if !self.is_connected(bus)? {
+            return Err(TcpSocketError::NotReady);
+        }
+
+        let max_size = self.socket.get_tx_free_size(bus)? as usize;
+
+        let write_data = if data.len() < max_size {
+            data
+        } else {
+            &data[..max_size]
+        };
+
+        // Append the data to the write buffer after the current write pointer.
+        let write_pointer = self.socket.get_tx_write_pointer(bus)?;
+
+        // Write data into the buffer and update the writer pointer.
+        bus.write_frame(self.socket.tx_buffer(), write_pointer, write_data)?;
+        self.socket
+            .set_tx_write_pointer(bus, write_pointer.wrapping_add(write_data.len() as u16))?;
+
+        // Send the data.
+        self.socket.command(bus, socketn::Command::Send)?;
+
+        // Wait until the send command completes.
+        while !self.socket.has_interrupt(bus, socketn::Interrupt::SendOk)? {}
+        self.socket
+            .reset_interrupt(bus, socketn::Interrupt::SendOk)?;
+
+        Ok(write_data.len())
+    }
+
+    fn receive<B: Bus>(
+        &mut self,
+        bus: &mut B,
+        data: &mut [u8],
+    ) -> Result<usize, TcpSocketError<B::Error>> {
+        if !self.is_connected(bus)? {
+            return Err(TcpSocketError::NotReady);
+        }
+
+        // Check if we've received data.
+        if !self
+            .socket
+            .has_interrupt(bus, socketn::Interrupt::Receive)?
+        {
+            return Ok(0);
+        }
+
+        let rx_size = self.socket.get_receive_size(bus)? as usize;
+
+        let read_buffer = if rx_size > data.len() {
+            data
+        } else {
+            &mut data[..rx_size]
+        };
+
+        // Read from the RX ring buffer.
+        let read_pointer = self.socket.get_rx_read_pointer(bus)?;
+        bus.read_frame(self.socket.rx_buffer(), read_pointer, read_buffer)?;
+        self.socket
+            .set_rx_read_pointer(bus, read_pointer.wrapping_add(read_buffer.len() as u16))?;
+
+        // Register the reception as complete.
+        self.socket.command(bus, socketn::Command::Receive)?;
+        self.socket
+            .reset_interrupt(bus, socketn::Interrupt::Receive)?;
+
+        Ok(read_buffer.len())
+    }
+}
+
+impl<SpiBus: Bus, HostImpl: Host> TcpClientStack for DeviceRefMut<'_, SpiBus, HostImpl> {
+    type TcpSocket = TcpSocket;
+    type Error = TcpSocketError<SpiBus::Error>;
+
+    fn socket(&mut self) -> Result<TcpSocket, Self::Error> {
+        match self.take_socket() {
+            Some(socket) => Ok(TcpSocket { socket }),
+            None => Err(TcpSocketError::NoMoreSockets),
+        }
+    }
+
+    fn connect(
+        &mut self,
+        socket: &mut Self::TcpSocket,
+        remote: SocketAddr,
+    ) -> nb::Result<(), Self::Error> {
+        if let SocketAddr::V4(remote) = remote {
+            // TODO dynamically select a random port
+            socket.open(&mut self.bus, 49849 + u16::from(socket.socket.index))?; // chosen by fair dice roll.
+            socket.connect(&mut self.bus, remote)?;
+
+            Ok(())
+        } else {
+            Err(nb::Error::Other(Self::Error::UnsupportedAddress))
+        }
+    }
+
+    fn is_connected(&mut self, socket: &Self::TcpSocket) -> Result<bool, Self::Error> {
+        socket.is_connected(&mut self.bus)
+    }
+
+    fn send(
+        &mut self,
+        socket: &mut Self::TcpSocket,
+        buffer: &[u8],
+    ) -> nb::Result<usize, Self::Error> {
+        let len = socket.send(&mut self.bus, buffer)?;
+        Ok(len)
+    }
+
+    fn receive(
+        &mut self,
+        socket: &mut Self::TcpSocket,
+        buffer: &mut [u8],
+    ) -> nb::Result<usize, Self::Error> {
+        Ok(socket.receive(&mut self.bus, buffer)?)
+    }
+
+    fn close(&mut self, socket: Self::TcpSocket) -> Result<(), Self::Error> {
+        socket.close(&mut self.bus)?;
+        self.release_socket(socket.socket);
+        Ok(())
+    }
+}
+
+impl<SpiBus: Bus, HostImpl: Host> TcpClientStack for Device<SpiBus, HostImpl> {
+    type TcpSocket = TcpSocket;
+    type Error = TcpSocketError<SpiBus::Error>;
+
+    fn socket(&mut self) -> Result<TcpSocket, Self::Error> {
+        self.as_mut().socket()
+    }
+
+    fn connect(
+        &mut self,
+        socket: &mut Self::TcpSocket,
+        remote: SocketAddr,
+    ) -> nb::Result<(), Self::Error> {
+        self.as_mut().connect(socket, remote)
+    }
+
+    fn is_connected(&mut self, socket: &Self::TcpSocket) -> Result<bool, Self::Error> {
+        self.as_mut().is_connected(socket)
+    }
+
+    fn send(
+        &mut self,
+        socket: &mut Self::TcpSocket,
+        buffer: &[u8],
+    ) -> nb::Result<usize, Self::Error> {
+        self.as_mut().send(socket, buffer)
+    }
+
+    fn receive(
+        &mut self,
+        socket: &mut Self::TcpSocket,
+        buffer: &mut [u8],
+    ) -> nb::Result<usize, Self::Error> {
+        self.as_mut().receive(socket, buffer)
+    }
+
+    fn close(&mut self, socket: Self::TcpSocket) -> Result<(), Self::Error> {
+        self.as_mut().close(socket)
+    }
+}

src/udp.rs

@@ -51,7 +51,7 @@ impl UdpSocket {
         // TODO ensure write is currently possible
         self.socket
             .set_tx_read_pointer(bus, 0)
-            .and_then(|_| bus.write_frame(self.socket.tx_buffer(), 0, &send_buffer))
+            .and_then(|_| bus.write_frame(self.socket.tx_buffer(), 0, send_buffer))
             .and_then(|_| {
                 self.socket
                     .set_tx_write_pointer(bus, send_buffer.len() as u16)

src/uninitialized_device.rs

@@ -12,6 +12,7 @@ pub struct UninitializedDevice<SpiBus: Bus> {
     bus: SpiBus,
 }
 
+#[derive(Debug)]
 #[repr(u8)]
 pub enum InitializeError<SpiError> {
     SpiError(SpiError),