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. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 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, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * */ #include <stdio.h> #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 machine\n" "rpcap://hostname:port ==> lists interfaces in a remote machine\n" " (rpcapd daemon must be up and running\n" " and it must accept 'null' authentication)\n" "file://foldername ==> lists all pcap files in the give folder\n\n" "Enter your choice: "); fgets(source, PCAP_ERRBUF_SIZE, stdin); source[PCAP_ERRBUF_SIZE] = '\0'; /* 获得接口列表 */ if (pcap_findalldevs_ex(source, NULL, &alldevs, errbuf) == -1) { fprintf(stderr,"Error in pcap_findalldevs: %s\n",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\n",d->name); /* 设备描述(Description) */ if (d->description) printf("\tDescription: %s\n",d->description); /* 回环地址*/ printf("\tLoopback: %s\n",(d->flags & PCAP_IF_LOOPBACK)?"yes":"no"); /* IP 地址 */ for(a=d->addresses;a;a=a->next) { printf("\tAddress Family: #%d\n",a->addr->sa_family); switch(a->addr->sa_family) { case AF_INET: printf("\tAddress Family Name: AF_INET\n"); if (a->addr) printf("\tAddress: %s\n",iptos(((struct sockaddr_in *)a->addr)->sin_addr.s_addr)); if (a->netmask) printf("\tNetmask: %s\n",iptos(((struct sockaddr_in *)a->netmask)->sin_addr.s_addr)); if (a->broadaddr) printf("\tBroadcast Address: %s\n",iptos(((struct sockaddr_in *)a->broadaddr)->sin_addr.s_addr)); if (a->dstaddr) printf("\tDestination Address: %s\n",iptos(((struct sockaddr_in *)a->dstaddr)->sin_addr.s_addr)); break; case AF_INET6: printf("\tAddress Family Name: AF_INET6\n"); if (a->addr) printf("\tAddress: %s\n", ip6tos(a->addr, ip6str, sizeof(ip6str))); break; default: printf("\tAddress Family Name: Unknown\n"); 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); _snprintf_s(output[which], sizeof(output[which]), sizeof(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; }