Winpcap是一个强大的网络开发库，可以实现许多功能：获取可用的网络适配器；获取指定适配器信息（比如名称和描述信息）；捕获指定网卡的数据封包；发送数据封包；过滤捕获的包以获取特定包等。
首先到http://www.winpcap.org/install/default.htm下载安装winpcap 驱动和DLL组件。
然后到http://www.winpcap.org/devel.htm.下载winpcap开发包，解压到指定目录，这里我解压到C:\WpdPack_4_0_2\WpdPack，可以看到里面包含了：Lib,Include,文档和示例程序。
首先创建一个C++控制台程序，设置如下：
1） 在“Configuration Properties -> C/C++ -> General”中，在Additional Include Directories加入Include路径(“C:\WpdPack_4_0_2\WpdPack\Include”)。
2） 在 “Configuration Properties -> Linker -> General” 中，在Additional Library Directories中加入 winpcap 库文件路径 ( “C:\WpdPack_4_0_2\WpdPack\Lib” ) 。
3） 在“Configuration Properties -> Linker -> Input”中， Additional Dependencies 加入用到的两个winpcap 库文件（wpcap.lib and Packet.lib ) 。
4） 为了使用Winpcap的远程访问，必须在预处理器中加入HAVE_REMOTE
示例程序1 获取适配器列表
#include <pcap.h>
int _tmain(int argc, _TCHAR* argv[])
{
pcap_if_t * allAdapters;//适配器列表
pcap_if_t * adapter;
char errorBuffer[ PCAP_ERRBUF_SIZE ];//错误信息缓冲区
if( pcap_findalldevs_ex( PCAP_SRC_IF_STRING, NULL,
&allAdapters, errorBuffer ) == -1 )
{//检索机器连接的所有网络适配器
fprintf( stderr, "Error in pcap_findalldevs_ex function: %s\n", errorBuffer );
return -1;
}
if( allAdapters == NULL )
{//不存在人任何适配器
printf( "\nNo adapters found! Make sure WinPcap is installed.\n" );
return 0;
}
int crtAdapter = 0;
for( adapter = allAdapters; adapter != NULL; adapter = adapter->next)
{//遍历输入适配器信息(名称和描述信息)
printf( "\n%d.%s ", ++crtAdapter, adapter->name );
printf( "-- %s\n", adapter->description );
}
printf( "\n" );
pcap_freealldevs( allAdapters );//释放适配器列表
system( "PAUSE" );
return 0;
}
示例程序2 打开指定适配器并捕获数据包
#include <pcap.h>
int _tmain(int argc, _TCHAR* argv[])
{
pcap_if_t * allAdapters;//适配器列表
pcap_if_t * adapter;
pcap_t * adapterHandle;//适配器句柄
struct pcap_pkthdr * packetHeader;
const u_char * packetData;
char errorBuffer[ PCAP_ERRBUF_SIZE ];//错误信息缓冲区
if( pcap_findalldevs_ex( PCAP_SRC_IF_STRING, NULL,
&allAdapters, errorBuffer ) == -1 )
{//检索机器连接的所有网络适配器
fprintf( stderr, "Error in pcap_findalldevs_ex function: %s\n", errorBuffer );
return -1;
}
if( allAdapters == NULL )
{//不存在任何适配器
printf( "\nNo adapters found! Make sure WinPcap is installed.\n" );
return 0;
}
int crtAdapter = 0;
for( adapter = allAdapters; adapter != NULL; adapter = adapter->next)
{//遍历输入适配器信息(名称和描述信息)
printf( "\n%d.%s ", ++crtAdapter, adapter->name );
printf( "-- %s\n", adapter->description );
}
printf( "\n" );
//选择要捕获数据包的适配器
int adapterNumber;
printf( "Enter the adapter number between 1 and %d:", crtAdapter );
scanf_s( "%d", &adapterNumber );
if( adapterNumber < 1 || adapterNumber > crtAdapter )
{
printf( "\nAdapter number out of range.\n" );
// 释放适配器列表
pcap_freealldevs( allAdapters );
return -1;
}
adapter = allAdapters;
for( crtAdapter = 0; crtAdapter < adapterNumber - 1; crtAdapter++ )
adapter = adapter->next;
// 打开指定适配器
adapterHandle = pcap_open( adapter->name, // name of the adapter
65536, // portion of the packet to capture
// 65536 guarantees that the whole
// packet will be captured
PCAP_OPENFLAG_PROMISCUOUS, // promiscuous mode
1000, // read timeout - 1 millisecond
NULL, // authentication on the remote machine
errorBuffer // error buffer
);
if( adapterHandle == NULL )
{//指定适配器打开失败
fprintf( stderr, "\nUnable to open the adapter\n", adapter->name );
// 释放适配器列表
pcap_freealldevs( allAdapters );
return -1;
}
printf( "\nCapture session started on adapter %s
\n", adapter->name );
pcap_freealldevs( allAdapters );//释放适配器列表
// 开始捕获数据包
int retValue;
while( ( retValue = pcap_next_ex( adapterHandle,
&packetHeader,
&packetData ) ) >= 0 )
{
// timeout elapsed if we reach this point
if( retValue == 0 )
continue;
//打印捕获数据包的信息
printf( "length of packet: %d\n", packetHeader->len );
}
// if we get here, there was an error reading the packets
if( retValue == -1 )
{
printf( "Error reading the packets: %s\n", pcap_geterr( adapterHandle ) );
return -1;
}
system( "PAUSE" );
return 0;
}
示例程序3 发送数据封包
#include <pcap.h>
int _tmain(int argc, _TCHAR* argv[])
{
pcap_if_t * allAdapters;//适配器列表
pcap_if_t * adapter;
pcap_t * adapterHandle;//适配器句柄
u_char packet[ 20 ]; //待发送的数据封包
char errorBuffer[ PCAP_ERRBUF_SIZE ];//错误信息缓冲区
if( pcap_findalldevs_ex( PCAP_SRC_IF_STRING, NULL,
&allAdapters, errorBuffer ) == -1 )
{//检索机器连接的所有网络适配器
fprintf( stderr, "Error in pcap_findalldevs_ex function: %s\n", errorBuffer );
return -1;
}
if( allAdapters == NULL )
{//不存在人任何适配器
printf( "\nNo adapters found! Make sure WinPcap is installed.\n" );
return 0;
}
int crtAdapter = 0;
for( adapter = allAdapters; adapter != NULL; adapter = adapter->next)
{//遍历输入适配器信息(名称和描述信息)
printf( "\n%d.%s ", ++crtAdapter, adapter->name );
printf( "-- %s\n", adapter->description );
}
printf( "\n" );
//选择适配器
int adapterNumber;
printf( "Enter the adapter number between 1 and %d:", crtAdapter );
scanf_s( "%d", &adapterNumber );
if( adapterNumber < 1 || adapterNumber > crtAdapter )
{
printf( "\nAdapter number out of range.\n" );
// 释放适配器列表
pcap_freealldevs( allAdapters );
return -1;
}
adapter = allAdapters;
for( crtAdapter = 0; crtAdapter < adapterNumber - 1; crtAdapter++ )
adapter = adapter->next;
// 打开指定适配器
adapterHandle = pcap_open( adapter->name, // name of the adapter
65536, // portion of the packet to capture
// 65536 guarantees that the whole
// packet will be captured
PCAP_OPENFLAG_PROMISCUOUS, // promiscuous mode
1000, // read timeout - 1 millisecond
NULL, // authentication on the remote machine
errorBuffer // error buffer
);
if( adapterHandle == NULL )
{//指定适配器打开失败
fprintf( stderr, "\nUnable to open the adapter\n", adapter->name );
// 释放适配器列表
pcap_freealldevs( allAdapters );
return -1;
}
pcap_freealldevs( allAdapters );//释放适配器列表
//创建数据封包
// 设置目标的MAC地址为01 : 01 : 01 : 01 : 01 : 01
packet[0] = 0x01;
packet[1] = 0x01;
packet[2] = 0x01;
packet[3] = 0x01;
packet[4] = 0x01;
packet[5] = 0x01;
// 设置源的MAC地址为02 : 02 : 02 : 02 : 02 : 02
packet[6] = 0x02;
packet[7] = 0x02;
packet[8] = 0x02;
packet[9] = 0x02;
packet[10] = 0x02;
packet[11] = 0x02;
// 设置封包其他部分内容
for( int index = 12; index < 20; index++ )
{
packet[index] = 0xC4;
}
//发送数据封包
if( pcap_sendpacket( adapterHandle, // the adapter handle
packet, // the packet
20 // the length of the packet
) != 0 )
{
fprintf( stderr,"\nError sending the packet: \n", pcap_geterr( adapterHandle ) );
return -1;
}
system( "PAUSE" );
return 0;
}