这段代码为什么捕捉不到任何数据包？

linux:

// clang -o raw raw.c && ./raw #include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/socket.h> #include <netinet/in.h> #include <netinet/ip.h> #include <arpa/inet.h> #define BUFFER_SIZE 65536 int main(int argc, char *argv[]) { printf("Starting raw socket\n"); int sockfd, n; char buffer[BUFFER_SIZE]; struct sockaddr_in addr; struct iphdr *ip_header; // 创建 socket sockfd = socket(AF_INET, SOCK_RAW, IPPROTO_RAW); if (sockfd < 0) { perror("socket"); exit(EXIT_FAILURE); } // 设置 socket 选项 int on = 1; if (setsockopt(sockfd, IPPROTO_IP, IP_HDRINCL, &on, sizeof(on)) < 0) { perror("setsockopt"); exit(EXIT_FAILURE); } // 绑定地址 memset(&addr, 0, sizeof(addr)); addr.sin_family = AF_INET; addr.sin_addr.s_addr = INADDR_ANY; if (bind(sockfd, (struct sockaddr *)&addr, sizeof(addr)) < 0) { perror("bind"); exit(EXIT_FAILURE); } // 接收数据 printf("Waiting for packet\n"); while (1) { n = recv(sockfd, buffer, BUFFER_SIZE, 0); if (n < 0) { perror("recv"); exit(EXIT_FAILURE); } // 解析 IP 头部 ip_header = (struct iphdr *)buffer; printf("Received packet from %s\n", inet_ntoa(*(struct in_addr *)&ip_header->saddr)); } return 0; }