WinPcap: 获取已安装设备的高级信息

在第1讲中， (获取设备列表) 我们展示了如何获取适配器的基本信息 (如设备的名称和描述)。 事实上，WinPcap提供了其他更高级的信息。 特别需要指出的是， 由 pcap_findalldevs_ex() 返回的每一个 pcap_if 结构体，都包含一个 pcap_addr 结构体，这个结构体由如下元素组成：

• 一个地址列表
• 一个掩码列表 (each of which corresponds to an entry in the addresses list).
• 一个广播地址列表 (each of which corresponds to an entry in the addresses list).
• 一个目的地址列表 (each of which corresponds to an entry in the addresses list).

另外，函数 pcap_findalldevs_ex() 还能返回远程适配器信息和一个位于所给的本地文件夹的pcap文件列表。

下面的范例使用了ifprint()函数来打印出 pcap_if 结构体中所有的内容。程序对每一个由 pcap_findalldevs_ex() 函数返回的pcap_if，都调用ifprint()函数来实现打印。

/*
 * Copyright (c) 1999 - 2005 NetGroup, Politecnico di Torino (Italy)
 * Copyright (c) 2005 - 2006 CACE Technologies, Davis (California)
 * All rights reserved.
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 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
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 * 1. Redistributions of source code must retain the above copyright
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 * 2. Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the Politecnico di Torino, CACE Technologies 
 * nor the names of its contributors may be used to endorse or promote 
 * products derived from this software without specific prior written 
 * permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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#include "pcap.h"

#ifndef WIN32
    #include <sys/socket.h>
    #include <netinet/in.h>
#else
    #include <winsock.h>
#endif


// 函数原型
void ifprint(pcap_if_t *d);
char *iptos(u_long in);
char* ip6tos(struct sockaddr *sockaddr, char *address, int addrlen);


int main()
{
  pcap_if_t *alldevs;
  pcap_if_t *d;
  char errbuf[PCAP_ERRBUF_SIZE+1];
  char source[PCAP_ERRBUF_SIZE+1];

  printf("Enter the device you want to list:n"
            "rpcap://              ==> lists interfaces in the local machinen"
            "rpcap://hostname:port ==> lists interfaces in a remote machinen"
            "                          (rpcapd daemon must be up and runningn"
            "                           and it must accept 'null' authentication)n"
            "file://foldername     ==> lists all pcap files in the give foldernn"
            "Enter your choice: ");

  fgets(source, PCAP_ERRBUF_SIZE, stdin);
  source[PCAP_ERRBUF_SIZE] = '';

  /* 获得接口列表 */
  if (pcap_findalldevs_ex(source, NULL, &alldevs, errbuf) == -1)
  {
    fprintf(stderr,"Error in pcap_findalldevs: %sn",errbuf);
    exit(1);
  }

  /* 扫描列表并打印每一项 */
  for(d=alldevs;d;d=d->next)
  {
    ifprint(d);
  }

  pcap_freealldevs(alldevs);

  return 1;
}



/* 打印所有可用信息 */
void ifprint(pcap_if_t *d)
{
  pcap_addr_t *a;
  char ip6str[128];

  /* 设备名(Name) */
  printf("%sn",d->name);

  /* 设备描述(Description) */
  if (d->description)
    printf("tDescription: %sn",d->description);

  /* Loopback Address*/
  printf("tLoopback: %sn",(d->flags & PCAP_IF_LOOPBACK)?"yes":"no");

  /* IP addresses */
  for(a=d->addresses;a;a=a->next) {
    printf("tAddress Family: #%dn",a->addr->sa_family);
  
    switch(a->addr->sa_family)
    {
      case AF_INET:
        printf("tAddress Family Name: AF_INETn");
        if (a->addr)
          printf("tAddress: %sn",iptos(((struct sockaddr_in *)a->addr)->sin_addr.s_addr));
        if (a->netmask)
          printf("tNetmask: %sn",iptos(((struct sockaddr_in *)a->netmask)->sin_addr.s_addr));
        if (a->broadaddr)
          printf("tBroadcast Address: %sn",iptos(((struct sockaddr_in *)a->broadaddr)->sin_addr.s_addr));
        if (a->dstaddr)
          printf("tDestination Address: %sn",iptos(((struct sockaddr_in *)a->dstaddr)->sin_addr.s_addr));
        break;

      case AF_INET6:
        printf("tAddress Family Name: AF_INET6n");
        if (a->addr)
          printf("tAddress: %sn", ip6tos(a->addr, ip6str, sizeof(ip6str)));
       break;

      default:
        printf("tAddress Family Name: Unknownn");
        break;
    }
  }
  printf("n");
}



/* 将数字类型的IP地址转换成字符串类型的 */
#define IPTOSBUFFERS    12
char *iptos(u_long in)
{
    static char output[IPTOSBUFFERS][3*4+3+1];
    static short which;
    u_char *p;

    p = (u_char *)∈
    which = (which + 1 == IPTOSBUFFERS ? 0 : which + 1);
    sprintf(output[which], "%d.%d.%d.%d", p[0], p[1], p[2], p[3]);
    return output[which];
}

char* ip6tos(struct sockaddr *sockaddr, char *address, int addrlen)
{
    socklen_t sockaddrlen;

    #ifdef WIN32
    sockaddrlen = sizeof(struct sockaddr_in6);
    #else
    sockaddrlen = sizeof(struct sockaddr_storage);
    #endif


    if(getnameinfo(sockaddr, 
        sockaddrlen, 
        address, 
        addrlen, 
        NULL, 
        0, 
        NI_NUMERICHOST) != 0) address = NULL;

    return address;
}