274 lines
8.7 KiB
Rust
274 lines
8.7 KiB
Rust
/*! Access to networking hardware.
|
|
|
|
The `phy` module deals with the *network devices*. It provides a trait
|
|
for transmitting and receiving frames, [Device](trait.Device.html)
|
|
and implementations of it:
|
|
|
|
* the [_loopback_](struct.Loopback.html), for zero dependency testing;
|
|
* _middleware_ [Tracer](struct.Tracer.html) and
|
|
[FaultInjector](struct.FaultInjector.html), to facilitate debugging;
|
|
* _adapters_ [RawSocket](struct.RawSocket.html) and
|
|
[TapInterface](struct.TapInterface.html), to transmit and receive frames
|
|
on the host OS.
|
|
|
|
# Examples
|
|
|
|
An implementation of the [Device](trait.Device.html) trait for a simple hardware
|
|
Ethernet controller could look as follows:
|
|
|
|
```rust
|
|
use smoltcp::Result;
|
|
use smoltcp::phy::{self, DeviceCapabilities, Device};
|
|
use smoltcp::time::Instant;
|
|
|
|
struct StmPhy {
|
|
rx_buffer: [u8; 1536],
|
|
tx_buffer: [u8; 1536],
|
|
}
|
|
|
|
impl<'a> StmPhy {
|
|
fn new() -> StmPhy {
|
|
StmPhy {
|
|
rx_buffer: [0; 1536],
|
|
tx_buffer: [0; 1536],
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<'a> phy::Device<'a> for StmPhy {
|
|
type RxToken = StmPhyRxToken<'a>;
|
|
type TxToken = StmPhyTxToken<'a>;
|
|
|
|
fn receive(&'a mut self) -> Option<(Self::RxToken, Self::TxToken)> {
|
|
Some((StmPhyRxToken(&mut self.rx_buffer[..]),
|
|
StmPhyTxToken(&mut self.tx_buffer[..])))
|
|
}
|
|
|
|
fn transmit(&'a mut self) -> Option<Self::TxToken> {
|
|
Some(StmPhyTxToken(&mut self.tx_buffer[..]))
|
|
}
|
|
|
|
fn capabilities(&self) -> DeviceCapabilities {
|
|
let mut caps = DeviceCapabilities::default();
|
|
caps.max_transmission_unit = 1536;
|
|
caps.max_burst_size = Some(1);
|
|
caps
|
|
}
|
|
}
|
|
|
|
struct StmPhyRxToken<'a>(&'a mut [u8]);
|
|
|
|
impl<'a> phy::RxToken for StmPhyRxToken<'a> {
|
|
fn consume<R, F>(mut self, _timestamp: Instant, f: F) -> Result<R>
|
|
where F: FnOnce(&mut [u8]) -> Result<R>
|
|
{
|
|
// TODO: receive packet into buffer
|
|
let result = f(&mut self.0);
|
|
println!("rx called");
|
|
result
|
|
}
|
|
}
|
|
|
|
struct StmPhyTxToken<'a>(&'a mut [u8]);
|
|
|
|
impl<'a> phy::TxToken for StmPhyTxToken<'a> {
|
|
fn consume<R, F>(self, _timestamp: Instant, len: usize, f: F) -> Result<R>
|
|
where F: FnOnce(&mut [u8]) -> Result<R>
|
|
{
|
|
let result = f(&mut self.0[..len]);
|
|
println!("tx called {}", len);
|
|
// TODO: send packet out
|
|
result
|
|
}
|
|
}
|
|
```
|
|
*/
|
|
|
|
use crate::Result;
|
|
use crate::time::Instant;
|
|
|
|
#[cfg(all(any(feature = "phy-raw_socket", feature = "phy-tap_interface"), unix))]
|
|
mod sys;
|
|
|
|
mod tracer;
|
|
mod fault_injector;
|
|
mod fuzz_injector;
|
|
mod pcap_writer;
|
|
#[cfg(any(feature = "std", feature = "alloc"))]
|
|
mod loopback;
|
|
#[cfg(all(feature = "phy-raw_socket", unix))]
|
|
mod raw_socket;
|
|
#[cfg(all(feature = "phy-tap_interface", target_os = "linux"))]
|
|
mod tap_interface;
|
|
|
|
#[cfg(all(any(feature = "phy-raw_socket", feature = "phy-tap_interface"), unix))]
|
|
pub use self::sys::wait;
|
|
|
|
pub use self::tracer::Tracer;
|
|
pub use self::fault_injector::FaultInjector;
|
|
pub use self::fuzz_injector::{Fuzzer, FuzzInjector};
|
|
pub use self::pcap_writer::{PcapLinkType, PcapMode, PcapSink, PcapWriter};
|
|
#[cfg(any(feature = "std", feature = "alloc"))]
|
|
pub use self::loopback::Loopback;
|
|
#[cfg(all(feature = "phy-raw_socket", unix))]
|
|
pub use self::raw_socket::RawSocket;
|
|
#[cfg(all(feature = "phy-tap_interface", target_os = "linux"))]
|
|
pub use self::tap_interface::TapInterface;
|
|
|
|
#[cfg(feature = "ethernet")]
|
|
/// A tracer device for Ethernet frames.
|
|
pub type EthernetTracer<T> = Tracer<T, super::wire::EthernetFrame<&'static [u8]>>;
|
|
|
|
/// A description of checksum behavior for a particular protocol.
|
|
#[derive(Debug, Clone, Copy)]
|
|
pub enum Checksum {
|
|
/// Verify checksum when receiving and compute checksum when sending.
|
|
Both,
|
|
/// Verify checksum when receiving.
|
|
Rx,
|
|
/// Compute checksum before sending.
|
|
Tx,
|
|
/// Ignore checksum completely.
|
|
None,
|
|
}
|
|
|
|
impl Default for Checksum {
|
|
fn default() -> Checksum {
|
|
Checksum::Both
|
|
}
|
|
}
|
|
|
|
impl Checksum {
|
|
/// Returns whether checksum should be verified when receiving.
|
|
pub fn rx(&self) -> bool {
|
|
match *self {
|
|
Checksum::Both | Checksum::Rx => true,
|
|
_ => false
|
|
}
|
|
}
|
|
|
|
/// Returns whether checksum should be verified when sending.
|
|
pub fn tx(&self) -> bool {
|
|
match *self {
|
|
Checksum::Both | Checksum::Tx => true,
|
|
_ => false
|
|
}
|
|
}
|
|
}
|
|
|
|
/// A description of checksum behavior for every supported protocol.
|
|
#[derive(Debug, Clone, Default)]
|
|
pub struct ChecksumCapabilities {
|
|
pub ipv4: Checksum,
|
|
pub udp: Checksum,
|
|
pub tcp: Checksum,
|
|
#[cfg(feature = "proto-ipv4")]
|
|
pub icmpv4: Checksum,
|
|
#[cfg(feature = "proto-ipv6")]
|
|
pub icmpv6: Checksum,
|
|
dummy: (),
|
|
}
|
|
|
|
impl ChecksumCapabilities {
|
|
/// Checksum behavior that results in not computing or verifying checksums
|
|
/// for any of the supported protocols.
|
|
pub fn ignored() -> Self {
|
|
ChecksumCapabilities {
|
|
ipv4: Checksum::None,
|
|
udp: Checksum::None,
|
|
tcp: Checksum::None,
|
|
#[cfg(feature = "proto-ipv4")]
|
|
icmpv4: Checksum::None,
|
|
#[cfg(feature = "proto-ipv6")]
|
|
icmpv6: Checksum::None,
|
|
..Self::default()
|
|
}
|
|
}
|
|
}
|
|
|
|
/// A description of device capabilities.
|
|
///
|
|
/// Higher-level protocols may achieve higher throughput or lower latency if they consider
|
|
/// the bandwidth or packet size limitations.
|
|
#[derive(Debug, Clone, Default)]
|
|
pub struct DeviceCapabilities {
|
|
/// Maximum transmission unit.
|
|
///
|
|
/// The network device is unable to send or receive frames larger than the value returned
|
|
/// by this function.
|
|
///
|
|
/// For Ethernet, MTU will fall between 576 (for IPv4) or 1280 (for IPv6) and 9216 octets.
|
|
pub max_transmission_unit: usize,
|
|
|
|
/// Maximum burst size, in terms of MTU.
|
|
///
|
|
/// The network device is unable to send or receive bursts large than the value returned
|
|
/// by this function.
|
|
///
|
|
/// If `None`, there is no fixed limit on burst size, e.g. if network buffers are
|
|
/// dynamically allocated.
|
|
pub max_burst_size: Option<usize>,
|
|
|
|
/// Checksum behavior.
|
|
///
|
|
/// If the network device is capable of verifying or computing checksums for some protocols,
|
|
/// it can request that the stack not do so in software to improve performance.
|
|
pub checksum: ChecksumCapabilities,
|
|
|
|
/// Only present to prevent people from trying to initialize every field of DeviceLimits,
|
|
/// which would not let us add new fields in the future.
|
|
dummy: ()
|
|
}
|
|
|
|
/// An interface for sending and receiving raw network frames.
|
|
///
|
|
/// The interface is based on _tokens_, which are types that allow to receive/transmit a
|
|
/// single packet. The `receive` and `transmit` functions only construct such tokens, the
|
|
/// real sending/receiving operation are performed when the tokens are consumed.
|
|
pub trait Device<'a> {
|
|
type RxToken: RxToken + 'a;
|
|
type TxToken: TxToken + 'a;
|
|
|
|
/// Construct a token pair consisting of one receive token and one transmit token.
|
|
///
|
|
/// The additional transmit token makes it possible to generate a reply packet based
|
|
/// on the contents of the received packet. For example, this makes it possible to
|
|
/// handle arbitrarily large ICMP echo ("ping") requests, where the all received bytes
|
|
/// need to be sent back, without heap allocation.
|
|
fn receive(&'a mut self) -> Option<(Self::RxToken, Self::TxToken)>;
|
|
|
|
/// Construct a transmit token.
|
|
fn transmit(&'a mut self) -> Option<Self::TxToken>;
|
|
|
|
/// Get a description of device capabilities.
|
|
fn capabilities(&self) -> DeviceCapabilities;
|
|
}
|
|
|
|
/// A token to receive a single network packet.
|
|
pub trait RxToken {
|
|
/// Consumes the token to receive a single network packet.
|
|
///
|
|
/// This method receives a packet and then calls the given closure `f` with the raw
|
|
/// packet bytes as argument.
|
|
///
|
|
/// The timestamp must be a number of milliseconds, monotonically increasing since an
|
|
/// arbitrary moment in time, such as system startup.
|
|
fn consume<R, F>(self, timestamp: Instant, f: F) -> Result<R>
|
|
where F: FnOnce(&mut [u8]) -> Result<R>;
|
|
}
|
|
|
|
/// A token to transmit a single network packet.
|
|
pub trait TxToken {
|
|
/// Consumes the token to send a single network packet.
|
|
///
|
|
/// This method constructs a transmit buffer of size `len` and calls the passed
|
|
/// closure `f` with a mutable reference to that buffer. The closure should construct
|
|
/// a valid network packet (e.g. an ethernet packet) in the buffer. When the closure
|
|
/// returns, the transmit buffer is sent out.
|
|
///
|
|
/// The timestamp must be a number of milliseconds, monotonically increasing since an
|
|
/// arbitrary moment in time, such as system startup.
|
|
fn consume<R, F>(self, timestamp: Instant, len: usize, f: F) -> Result<R>
|
|
where F: FnOnce(&mut [u8]) -> Result<R>;
|
|
}
|