winPcap_4_获取已安装设备的高级信息

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。

#include "pcap.h"
#pragma comment(lib, "wpcap.lib")
#pragma comment(lib, "Packet.lib")
#pragma comment(lib, "wsock32.lib")



#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:
"
            "rpcap://              ==> lists interfaces in the local machine
"
            "rpcap://hostname:port ==> lists interfaces in a remote machine
"
            "                          (rpcapd daemon must be up and running
"
            "                           and it must accept 'null' authentication)
"
            "file://foldername     ==> lists all pcap files in the give folder

"
            "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: %s
",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("%s
",d->name);

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

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

  /* IP addresses */
  for(a=d->addresses;a;a=a->next) {
    printf("	Address Family: #%d
",a->addr->sa_family);
  
    switch(a->addr->sa_family)
    {
      case AF_INET:
        printf("	Address Family Name: AF_INET
");
        if (a->addr)
          printf("	Address: %s
",iptos(((struct sockaddr_in *)a->addr)->sin_addr.s_addr));
        if (a->netmask)
          printf("	Netmask: %s
",iptos(((struct sockaddr_in *)a->netmask)->sin_addr.s_addr));
        if (a->broadaddr)
          printf("	Broadcast Address: %s
",iptos(((struct sockaddr_in *)a->broadaddr)->sin_addr.s_addr));
        if (a->dstaddr)
          printf("	Destination Address: %s
",iptos(((struct sockaddr_in *)a->dstaddr)->sin_addr.s_addr));
        break;
/*
      case AF_INET6:
        printf("	Address Family Name: AF_INET6
");
        if (a->addr)
          printf("	Address: %s
", ip6tos(a->addr, ip6str, sizeof(ip6str)));
       break;
*/
      default:
        printf("	Address Family Name: Unknown
");
        break;
    }
  }
  printf("
");
}



/* 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 *)&in;
    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;
}
*/

　　结果：

此处只能显示电脑的ipv4的网卡信息，不知道为什么不能有ipv6的代码时，不能编译通过，不知道是包不支持，还是系统不支持；

int pcap_findalldevs_ex  ( char *  source,  
  struct pcap_rmtauth *  auth,  
  pcap_if_t **  alldevs,  
  char *  errbuf   
 ) 

　　·该函数请查看前一篇；

struct pcap_rmtauth{
　　int    type
     //Type of the authentication required.
　　char *    username
     //Zero-terminated string containing the username that has to be used on the remote machine for authentication.
　　char *    password
     //Zero-terminated string containing the password that has to be used on the remote machine for authentication. 
};

typedef struct pcap_if pcap_if_t;

struct  pcap_if {
    pcap_if *    next
    //if not NULL, a pointer to the next element in the list; NULL for the last element of the list
    char *    name
    //a pointer to a string giving a name for the device to pass to pcap_open_live()
    char *    description
    //if not NULL, a pointer to a string giving a human-readable description of the device
    pcap_addr *    addresses
    //a pointer to the first element of a list of addresses for the interface
    u_int    flags
    //PCAP_IF_ interface flags. Currently the only possible flag is PCAP_IF_LOOPBACK, that is set if the interface is a loopback interface.
};

typedef struct pcap_addr pcap_addr_t;

struct  pcap_addr
{
    pcap_addr *    next
    //if not NULL, a pointer to the next element in the list; NULL for the last element of the list
    sockaddr *    addr
    //a pointer to a struct sockaddr containing an address
    sockaddr *    netmask
    //if not NULL, a pointer to a struct sockaddr that contains the netmask corresponding to the address pointed to by addr.
    sockaddr *    broadaddr
    //if not NULL, a pointer to a struct sockaddr that contains the broadcast address corre­ sponding to the address pointed to by addr; may be null if the interface doesn't support broadcasts
    sockaddr *    dstaddr
    //if not NULL, a pointer to a struct sockaddr that contains the destination address corre­ sponding to the address pointed to by addr; may be null if the interface isn't a point- to-point interface
};

struct sockaddr {
    unsigned short sa_family;
    char           sa_data[14];
};

 　　·详细的请看前面的socket编程；

struct sockaddr_in{
    short                 sin_family;
    unsigned short        sin_port;
    struct   in_addr      sin_addr;
    char                  sin_zero[8];
};

in_addr

The in_addr structure represents a host by its Internet address.

struct in_addr {
  union {
          struct { u_char s_b1,s_b2,s_b3,s_b4; }   S_un_b;
          struct { u_short s_w1,s_w2; }            S_un_w;
          u_long                                   S_addr;
  } S_un;
};

Members

S_un_b

Address of the host formatted as four u_chars.

S_un_w

Address of the host formatted as two u_shorts.

S_addr

Address of the host formatted as a u_long. 

fgets, fgetws

Get a string from a stream.

char *fgets( char *string, int n, FILE *stream );

wchar_t *fgetws( wchar_t *string, int n, FILE *stream );