linux c ip数据包

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>

#define BUF_SIZE 1024

int main() {
    int sockfd;
    struct sockaddr_in addr;
    char buffer[BUF_SIZE];

    // 创建原始套接字
    if ((sockfd = socket(AF_INET, SOCK_RAW, IPPROTO_TCP)) == -1) {
        perror("socket");
        exit(EXIT_FAILURE);
    }

    memset(&addr, 0, sizeof(addr));
    addr.sin_family = AF_INET;
    addr.sin_addr.s_addr = htonl(INADDR_ANY);

    while (1) {
        ssize_t len = recvfrom(sockfd, buffer, BUF_SIZE, 0, NULL, NULL);
        if (len == -1) {
            perror("recvfrom");
            continue;
        }
        printf("Received packet of length %zd\n", len);
        // 这里可以添加更多的数据包处理逻辑
    }

    close(sockfd);
    return 0;
}