init

crates/pause-spammer/Cargo.toml

@@ -0,0 +1,14 @@
+[package]
+name = "pause-spammer"
+version = "0.1.0"
+edition.workspace = true
+
+[dependencies]
+clap = { version = "4.5.18", features = ["derive"] }
+humantime = "2.1.0"
+pnet = "0.35.0"
+tracing = "0.1.40"
+tracing-subscriber = "0.3.18"
+
+[lints]
+workspace = true

crates/pause-spammer/src/main.rs

@@ -0,0 +1,73 @@
+//! Ethernet PAUSE frame spammer.
+
+use clap::Parser;
+use pnet::datalink;
+use pnet::datalink::Channel::Ethernet;
+use pnet::packet::Packet;
+use pnet::packet::ethernet::MutableEthernetPacket;
+use pnet::util::MacAddr;
+
+/// Command line options
+#[derive(Debug, Parser)]
+pub struct Cli {
+    #[arg(long)]
+    interface_name: String,
+
+    #[arg(long, default_value = "100ms")]
+    interval: humantime::Duration,
+
+    #[arg(long, default_value_t = u16::MAX)]
+    pause_time: u16,
+}
+
+fn main() {
+    tracing_subscriber::fmt::init();
+    let Cli {
+        interface_name,
+        interval,
+        pause_time,
+    } = Cli::parse();
+
+    // Find the network interface with the provided name
+    let interfaces = datalink::interfaces();
+    let interface = interfaces.iter().find(|iface| iface.name == interface_name).unwrap_or_else(|| {
+        panic!(
+            "No interface with name {interface_name} found in interfaces: {}",
+            interfaces.iter().map(|iface| iface.name.clone()).collect::<Vec<_>>().join(", ")
+        )
+    });
+
+    tracing::info!("Interface: {interface}");
+
+    // Create a new channel, dealing with layer 2 packets
+    let (mut tx, _rx) = match datalink::channel(interface, Default::default()) {
+        Ok(Ethernet(tx, rx)) => (tx, rx),
+        Ok(_) => panic!("Unhandled channel type"),
+        Err(err) => panic!("An error occurred when creating the datalink channel: {err}"),
+    };
+
+    loop {
+        // Create a PAUSE frame
+        let mut buffer = [0u8; 60]; // Minimum Ethernet frame size
+        let mut ethernet_packet = MutableEthernetPacket::new(&mut buffer).unwrap();
+
+        // Set Ethernet header
+        ethernet_packet.set_destination(MacAddr::new(0x01, 0x80, 0xC2, 0x00, 0x00, 0x01));
+        ethernet_packet.set_source(interface.mac.unwrap());
+        ethernet_packet.set_ethertype(pnet::packet::ethernet::EtherType::new(0x8808));
+
+        // Set PAUSE frame payload
+        // Payload format: [Opcode (2 bytes), Pause time (2 bytes)]
+        let mut pause_frame = [0u8; 4];
+        const PAUSE_OPCODE: u16 = 0x0001;
+        pause_frame[0..2].copy_from_slice(&PAUSE_OPCODE.to_be_bytes());
+        pause_frame[2..4].copy_from_slice(&pause_time.to_be_bytes());
+
+        ethernet_packet.set_payload(&pause_frame);
+
+        tracing::info!("Sending PAUSE frame {ethernet_packet:?} with pause time {pause_time}");
+        tx.send_to(ethernet_packet.packet(), None);
+
+        std::thread::sleep(interval.into());
+    }
+}