自定义Linux网络协议的开发与测试

#include <linux/module.h> #include <linux/kernel.h> #include <linux/net.h> #include <linux/socket.h> #include <linux/skbuff.h> #include <linux/netdevice.h> #include <net/sock.h> #include <linux/init.h> #include <linux/uaccess.h> // 添加头文件以支持copy_to_user 和 copy_from_user #define AF_MYPROTO 28 #define PROTO_MYPROTO 128 // 定义一个简单的缓冲区 static char myproto_buffer[1024]; static int buffer_length = 0; int myproto_release(struct socket *sock) { return 0; } static int myproto_create(struct net *net, struct socket *sock, int protocol, int kern); static int myproto_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len); static int myproto_recvmsg(struct socket *sock, struct msghdr *m, size_t total_len, int flags); static struct proto_ops myproto_ops = { .family = AF_MYPROTO, .owner = THIS_MODULE, .release = myproto_release, .bind = sock_no_bind, .connect = sock_no_connect, .socketpair = sock_no_socketpair, .accept = sock_no_accept, .getname = sock_no_getname, .poll = datagram_poll, .ioctl = sock_no_ioctl, .listen = sock_no_listen, .shutdown = sock_no_shutdown, .setsockopt = sock_no_setsockopt, .getsockopt = sock_no_getsockopt, .sendmsg = myproto_sendmsg, .recvmsg = myproto_recvmsg, .mmap = sock_no_mmap, .sendpage = sock_no_sendpage, }; static struct net_proto_family myproto_family_ops = { .family = AF_MYPROTO, .create = myproto_create, .owner = THIS_MODULE, }; static int myproto_create(struct net *net, struct socket *sock, int protocol, int kern) { if (protocol && protocol != PROTO_MYPROTO) return -EPROTONOSUPPORT; sock->ops = &myproto_ops; return 0; } static int myproto_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len) { int len = min_t(size_t, total_len, sizeof(myproto_buffer) - buffer_length); if (len > 0) { // 检查并处理 copy_from_user 的返回值 if (copy_from_user(myproto_buffer + buffer_length, m->msg_iter.iov->iov_base, len)) { return -EFAULT; } buffer_length += len; } return len; } static int myproto_recvmsg(struct socket *sock, struct msghdr *m, size_t total_len, int flags) { int len = min_t(size_t, total_len, buffer_length); if (len > 0) { // 检查并处理 copy_to_user 的返回值 if (copy_to_user(m->msg_iter.iov->iov_base, myproto_buffer, len)) { return -EFAULT; } memmove(myproto_buffer, myproto_buffer + len, buffer_length - len); buffer_length -= len; } return len; } static int __init myproto_init(void) { int ret; ret = sock_register(&myproto_family_ops); if (ret) { printk(KERN_ERR "Failed to register myproto socket\n"); } else { printk(KERN_INFO "Registered myproto socket\n"); } return ret; } static void __exit myproto_exit(void) { sock_unregister(AF_MYPROTO); printk(KERN_INFO "Unregistered myproto socket\n"); } module_init(myproto_init); module_exit(myproto_exit); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Your Name"); MODULE_DESCRIPTION("My Protocol Socket Example");