Rust中如何查看ping值？

在Rust中查看ping值，可以使用Nping工具，它是一个基于ICMP协议的实时可视化Ping工具。

在Rust中实现ping功能，可以通过使用std::net库和ICMP协议来完成，本文将详细介绍如何使用Rust编写一个ping工具，包括命令行参数解析、周期性发送ping请求、处理响应以及监听退出信号等步骤。

一、命令行参数解析

在Rust中，可以使用clap crate来解析命令行参数，clap是一个功能强大且易于使用的库，可以自动生成帮助信息和使用说明，以下是一个简单的例子，展示了如何定义和解析ping命令的参数：

use clap::{Arg, Command};
#[derive(Parser, Debug)]
#[command(author = "Your Name", version = "1.0", about = "A Rust implementation of ping", long_about = None)]
pub struct Args {
    /// Count of ping times
    #[arg(short, default_value_t = 4)]
    count: u16,
    /// Ping packet size
    #[arg(short = 's', default_value_t = 64)]
    packet_size: usize,
    /// Ping ttl
    #[arg(short = 't', default_value_t = 64)]
    ttl: u32,
    /// Ping timeout seconds
    #[arg(short = 'w', default_value_t = 1)]
    timeout: u64,
    /// Ping interval duration milliseconds
    #[arg(short = 'i', default_value_t = 1000)]
    interval: u64,
    /// Ping destination, ip or domain
    #[arg(value_parser=Address::parse)]
    destination: Address,
}

二、实现Ping功能

1. 定义ICMP包

首先需要定义一个ICMP包，可以使用pnet库中的ICMP包定义，然后设置ICMP包的类型为EchoRequest（即ping请求），并填充其他必要的字段如序列号、标识符和校验和。

use pnet::datalink::{Channel as DataLinkChannel, MutableEchoRequestPacket};
use pnet::datalink::Channel::new;
use pnet::datalink::config::Config;
use pnet::datalink::Error as DataLinkError;
use pnet::datalink::MacAddr;
use pnet::util::checksum;
use std::time::Duration;
use std::thread;
use std::sync::{Arc, Mutex};
use std::sync::mpsc::channel;
use std::collections::HashMap;
use std::io::Result;
fn create_icmp_packet() > Result<Vec<u8>> {
    let mut buf = vec![0; 64]; // ICMP packet size
    let mut icmp = MutableEchoRequestPacket::new(&mut buf[..]).ok_or(DataLinkError::InvalidBufferSize)?;
    icmp.set_icmp_type(IcmpTypes::EchoRequest); // Set to EchoRequest type
    icmp.set_icmp_code(IcmpCodes::NoCode);
    icmp.set_sequence_number(0); // Sequence number
    icmp.set_identifier(0);
    icmp.set_checksum(checksum(&icmp.packet(), 1)); // Checksum function
    Ok(icmp.packet())
}

2. 发送请求

通过socket2库发送ICMP包，并设置超时时间和TTL值。

use socket2::{Socket, Domain, Type, Protocol, SockAddr};
use std::net::Ipv4Addr;
use std::time::Instant;
use std::thread;
use std::sync::{Arc, Mutex};
use std::sync::mpsc::channel;
use std::collections::HashMap;
use std::io::Result;
fn send_ping(destination: &str, count: u16, packet_size: usize, ttl: u32, timeout: u64, interval: u64) > Result<()> {
    let socket = Socket::new(Domain::IPV4, Type::DGRAM, Some(Protocol::ICMPV4))?;
    let src = SocketAddr::new(Ipv4Addr::UNSPECIFIED, 0);
    socket.bind(&src.into())?;
    socket.set_ttl(Some(ttl))?;
    socket.set_read_timeout(Some(Duration::from_secs(timeout as u64)))?;
    socket.set_write_timeout(Some(Duration::from_secs(timeout as u64)))?;
    for _ in 0..count {
        let icmp_packet = create_icmp_packet()?;
        socket.send_to(&icmp_packet, &SockAddr::new(destination.parse().unwrap(), 0))?;
        thread::sleep(Duration::from_millis(interval));
    }
    Ok(())
}

3. 处理响应

接收响应并将其转换为pnet中的EchoReplyPacket。

fn receive_ping(socket: &mut Socket) > Result<()> {
    let mut mem_buf = unsafe { &mut *(buf.as_mut_slice() as *mut [u8] as *mut [std::mem::MaybeUninit<u8>]) };
    let (size, _) = socket.recv_from(&mut mem_buf)?;
    let reply = EchoReplyPacket::new(&buf).ok_or(RingError::InvalidPacket)?;
    println!("Received response from {}", reply.get_source());
    Ok(())
}

三、周期性发送Ping请求

通过多线程实现周期性发送ping请求，并汇小编总结果，可以使用thread和Mutex来实现线程安全的数据共享。

use std::sync::{Arc, Mutex};
use std::sync::mpsc::channel;
use std::collections::HashMap;
use std::io::Result;
fn periodic_ping(args: Arc<Args>) {
    let socket = Arc::new(Mutex::new(Socket::new(Domain::IPV4, Type::DGRAM, Some(Protocol::ICMPV4)).unwrap()));
    let (tx, rx) = channel();
    let handle = thread::spawn(move || {
        for _ in 0..args.count {
            let icmp_packet = create_icmp_packet().unwrap();
            socket.lock().unwrap().send_to(&icmp_packet, &SockAddr::new(args.destination.parse().unwrap(), 0)).unwrap();
            thread::sleep(Duration::from_millis(args.interval));
        }
        tx.send(()).unwrap();
    });
    drop(handle);
    rx.recv().unwrap();
}

四、监听退出信号

通过监听系统信号实现优雅退出，可以使用ctrlc库来捕获Ctrl+C信号。

use ctrlc;
use std::sync::atomic::{AtomicBool, Ordering};
use std::sync::Arc;
use std::thread;
fn main() {
    let args = Args::parse();
    let running = Arc::new(AtomicBool::new(true));
    let rx = Arc::clone(&running);
    ctrlc::set_handler(move || {
        rx.store(false, Ordering::SeqCst);
    }).expect("Error setting CtrlC handler");
    periodic_ping(Arc::new(args));
}