#include "stdafx.h"
#include "pcap.h"
#include"remote-ext.h"
typedef struct ip_address {
u_char byte1;
u_char byte2;
u_char byte3;
u_char byte4;
}ip_address;
typedef struct ip_header {
u_char ver_ihl;
u_char tos;
u_short tlen;
u_short identification;
u_short flags_fo;
u_char ttl;
u_char proto;
u_short crc;
ip_address saddr;
ip_address daddr;
u_int op_pad;
}ip_header;
typedef struct udp_header {
u_short sport;
u_short dport;
u_short len;
u_short crc;
}udp_header;
/* packet handler 函数原型 */
void packet_handler(u_char *param, const struct pcap_pkthdr *header, const u_char *pkt_data)
{
struct tm *ltime;
char timestr[16];
ip_header *ih;
udp_header *uh;
u_int ip_len;
u_short sport, dport;
time_t local_tv_sec;
local_tv_sec = header->ts.tv_sec;
ltime = localtime(&local_tv_sec);
strftime(timestr, sizeof timestr, "H:%M:%S", ltime);
printf("%s.%.6d len:%d", timestr, header->ts.tv_usec, header->len);
ih = (ip_header *)(pkt_data + 14);
ip_len = (ih->ver_ihl & 0xf) * 4;
uh = (udp_header *)((u_char*)ih + ip_len);
sport = ntohs(uh->sport);
dport = ntohs(uh->dport);
printf("%d.%d.%d.%d.%d -> %d.%d.%d.%d.%d\n",
ih->saddr.byte1,
ih->saddr.byte2,
ih->saddr.byte3,
ih->saddr.byte4,
sport,
ih->daddr.byte1,
ih->daddr.byte2,
ih->daddr.byte3,
ih->daddr.byte4,
dport);
}
int _tmain(int argc, _TCHAR* argv[])
{
pcap_if_t *alldevs;
pcap_if_t *d;
int inum;
int i = 0;
pcap_t *adhandle;
char errbuf[PCAP_ERRBUF_SIZE];
u_int netmask;
char packet_filter[] = "ip and udp";
struct bpf_program fcode;
/* 获取本机设备列表 */
if (pcap_findalldevs_ex((char *)PCAP_SRC_IF_STRING, NULL, &alldevs, errbuf) == -1)
{
fprintf(stderr, "Error in pcap_findalldevs: %s\n", errbuf);
exit(1);
}
/* 打印列表 */
for (d = alldevs; d; d = d->next)
{
printf("%d. %s", ++i, d->name);
if (d->description)
printf(" (%s)\n", d->description);
else
printf(" (No description available)\n");
}
if (i == 0)
{
printf("\nNo interfaces found! Make sure WinPcap is installed.\n");
return -1;
}
printf("Enter the interface number (1-%d):", i);
scanf("%d", &inum);
if (inum < 1 || inum > i)
{
printf("\nInterface number out of range.\n");
/* 释放设备列表 */
pcap_freealldevs(alldevs);
return -1;
}
/* 跳转到选中的适配器 */
for (d = alldevs, i = 0; i< inum - 1; d = d->next, i++);
/* 打开设备 */
if ((adhandle = pcap_open(d->name, // 设备名
65536, // 65535保证能捕获到不同数据链路层上的每个数据包的全部内容
PCAP_OPENFLAG_PROMISCUOUS, // 混杂模式
1000, // 读取超时时间
NULL, // 远程机器验证
errbuf // 错误缓冲池
)) == NULL)
{
fprintf(stderr, "\nUnable to open the adapter. %s is not supported by WinPcap\n");
/* 释放设备列表 */
pcap_freealldevs(alldevs);
return -1;
}
if (pcap_datalink(adhandle) != DLT_EN10MB)
{
fprintf(stderr, "\nThis program works only on Ethernet network.\n");
pcap_freealldevs(alldevs);
return -1;
}
if (d->addresses != NULL)
netmask = ((struct sockaddr_in *)(d->addresses->netmask))->sin_addr.S_un.S_addr;
else
netmask = 0xffffff;
if (pcap_compile(adhandle, &fcode, packet_filter, 1, netmask) < 0)
{
fprintf(stderr, "\nUnable to compile the packet filter.Check the syntax.\n");
pcap_freealldevs(alldevs);
return -1;
}
if (pcap_setfilter(adhandle, &fcode) < 0)
{
fprintf(stderr, "\nError setting the filter.\n");
pcap_freealldevs(alldevs);
return -1;
}
printf("\nlistening on %s...\n", d->description);
/* 释放设备列表 */
pcap_freealldevs(alldevs);
/* 开始捕获 */
pcap_loop(adhandle, 0, packet_handler, NULL);
return 0;
}
调用winpcap实现捕获数据包
求解决方案！
如果不用winpcap如何实现原始套接字捕获ip数据包。我在网上找到不少代码，已经基本看懂了原理，编译都没问题但是执行时接收不到任何数据。请大佬帮忙给一份可执行的代码，我的编译环境是vs2017，这周就得交作业了，希望最好能有注释。谢谢
