feat(driver/net): 实现Loopback网卡接口 (DragonOS-Community#845)

* 初步实现loopback设备

kernel/src/driver/net/mod.rs

@@ -11,6 +11,7 @@ use system_error::SystemError;
 mod dma;
 pub mod e1000e;
 pub mod irq_handle;
+pub mod loopback;
 pub mod virtio_net;
 
 pub trait NetDevice: Device {

kernel/src/init/initial_kthread.rs

@@ -35,10 +35,8 @@ fn kernel_init() -> Result<(), SystemError> {
 
     #[cfg(target_arch = "x86_64")]
     crate::driver::disk::ahci::ahci_init().expect("Failed to initialize AHCI");
-
     virtio_probe();
     mount_root_fs().expect("Failed to mount root fs");
-
     e1000e_init();
     net_init().unwrap_or_else(|err| {
         error!("Failed to initialize network: {:?}", err);
@@ -97,7 +95,6 @@ fn try_to_run_init_process(path: &str, trap_frame: &mut TrapFrame) -> Result<(),
         }
         return Err(e);
     }
-
     Ok(())
 }
 
@@ -107,6 +104,5 @@ fn run_init_process(path: String, trap_frame: &mut TrapFrame) -> Result<(), Syst
 
     compiler_fence(Ordering::SeqCst);
     Syscall::do_execve(path, argv, envp, trap_frame)?;
-
     Ok(())
 }

kernel/src/net/net_core.rs

@@ -43,7 +43,9 @@ pub fn net_init() -> Result<(), SystemError> {
 fn dhcp_query() -> Result<(), SystemError> {
     let binding = NET_DEVICES.write_irqsave();
 
-    let net_face = binding.get(&0).ok_or(SystemError::ENODEV)?.clone();
+    //由于现在os未实现在用户态为网卡动态分配内存，而lo网卡的id最先分配且ip固定不能被分配
+    //所以特判取用id为1的网卡（也就是virto_net）
+    let net_face = binding.get(&1).ok_or(SystemError::ENODEV)?.clone();
 
     drop(binding);
 

user/apps/test_lo/.gitignore

@@ -0,0 +1,3 @@
+/target
+Cargo.lock
+/install/

user/apps/test_lo/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "test_lo"
+version = "0.1.0"
+edition = "2021"
+description = "测试lo网卡功能"
+authors = [ "smallc <2628035541@qq.com>" ]
+

user/apps/test_lo/Makefile

@@ -0,0 +1,56 @@
+TOOLCHAIN=
+RUSTFLAGS=
+
+ifdef DADK_CURRENT_BUILD_DIR
+# 如果是在dadk中编译，那么安装到dadk的安装目录中
+	INSTALL_DIR = $(DADK_CURRENT_BUILD_DIR)
+else
+# 如果是在本地编译，那么安装到当前目录下的install目录中
+	INSTALL_DIR = ./install
+endif
+
+ifeq ($(ARCH), x86_64)
+	export RUST_TARGET=x86_64-unknown-linux-musl
+else ifeq ($(ARCH), riscv64)
+	export RUST_TARGET=riscv64gc-unknown-linux-gnu
+else 
+# 默认为x86_86，用于本地编译
+	export RUST_TARGET=x86_64-unknown-linux-musl
+endif
+
+run:
+	RUSTFLAGS=$(RUSTFLAGS) cargo $(TOOLCHAIN) run --target $(RUST_TARGET)
+
+build:
+	RUSTFLAGS=$(RUSTFLAGS) cargo $(TOOLCHAIN) build --target $(RUST_TARGET)
+
+clean:
+	RUSTFLAGS=$(RUSTFLAGS) cargo $(TOOLCHAIN) clean --target $(RUST_TARGET)
+
+test:
+	RUSTFLAGS=$(RUSTFLAGS) cargo $(TOOLCHAIN) test --target $(RUST_TARGET)
+
+doc:
+	RUSTFLAGS=$(RUSTFLAGS) cargo $(TOOLCHAIN) doc --target $(RUST_TARGET)
+
+fmt:
+	RUSTFLAGS=$(RUSTFLAGS) cargo $(TOOLCHAIN) fmt
+
+fmt-check:
+	RUSTFLAGS=$(RUSTFLAGS) cargo $(TOOLCHAIN) fmt --check
+
+run-release:
+	RUSTFLAGS=$(RUSTFLAGS) cargo $(TOOLCHAIN) run --target $(RUST_TARGET) --release
+
+build-release:
+	RUSTFLAGS=$(RUSTFLAGS) cargo $(TOOLCHAIN) build --target $(RUST_TARGET) --release
+
+clean-release:
+	RUSTFLAGS=$(RUSTFLAGS) cargo $(TOOLCHAIN) clean --target $(RUST_TARGET) --release
+
+test-release:
+	RUSTFLAGS=$(RUSTFLAGS) cargo $(TOOLCHAIN) test --target $(RUST_TARGET) --release
+
+.PHONY: install
+install:
+	RUSTFLAGS=$(RUSTFLAGS) cargo $(TOOLCHAIN) install --target $(RUST_TARGET) --path . --no-track --root $(INSTALL_DIR) --force

user/apps/test_lo/README.md

@@ -0,0 +1,7 @@
+# test-lo 
+
+lo网卡功能测试程序
+
+## 测试过程：
+
+通过创建一个UDP套接字，然后发送一条消息到本地回环地址127.0.0.1（lo网卡），再接收并验证这条消息，以此来测试lo网卡的功能。期望发送的消息和接收到的消息是完全一样的。通过日志输出查看测试是否成功。

user/apps/test_lo/src/main.rs

@@ -0,0 +1,25 @@
+use std::net::UdpSocket;
+use std::str;
+
+fn main() -> std::io::Result<()> {
+    let socket = UdpSocket::bind("127.0.0.1:34254")?;
+    socket.connect("127.0.0.1:34254")?;
+
+    let msg = "Hello, loopback!";
+    socket.send(msg.as_bytes())?;
+
+    let mut buf = [0; 1024];
+    let (amt, _src) = socket.recv_from(&mut buf)?;
+
+    let received_msg = str::from_utf8(&buf[..amt]).expect("Could not read buffer as UTF-8");
+
+    println!("Sent: {}", msg);
+    println!("Received: {}", received_msg);
+
+    assert_eq!(
+        msg, received_msg,
+        "The sent and received messages do not match!"
+    );
+
+    Ok(())
+}

user/dadk/config/test_lo_0_1_0.dadk

@@ -0,0 +1,27 @@
+{
+  "name": "test_lo",
+  "version": "0.1.0",
+  "description": "test for lo interface",
+  "rust_target": null,
+  "task_type": {
+    "BuildFromSource": {
+      "Local": {
+        "path": "apps/test_lo"
+      }
+    }
+  },
+  "depends": [],
+  "build": {
+    "build_command": "make install"
+  },
+  "install": {
+    "in_dragonos_path": "/"
+  },
+  "clean": {
+    "clean_command": "make clean"
+  },
+  "envs": [],
+  "build_once": false,
+  "install_once": false,
+  "target_arch": ["x86_64"]
+}