使用WinPcap编程

阳光穿透心脏的1/2处 2022-09-17 06:20 251阅读 0赞

## 创建一个使用 *wpcap.dll* 的应用程序 ##

用 Microsoft Visual C++ 创建一个使用 *wpcap.dll* 的应用程序，需要按一下步骤：

*  在每一个使用了库的源程序中，将 *pcap.h* 头文件包含(include)进来。
 *  如果你在程序中使用了WinPcap中提供给Win32平台的特有的函数， 记得在预处理中加入*WPCAP*的定义。
 *  如果你的程序使用了WinPcap的远程捕获功能，那么在预处理定义中加入*HAVE\_REMOTE*。**不要**直接把remote-ext.h直接加入到你的源文件中去。  
 *  设置VC++的链接器(Linker)，把*wpcap.lib*库文件包含进来。*wpcap.lib*可以在WinPcap中找到。    
 *  设置VC++的链接器(Linker)，把*ws2\_32.lib*库文件包含进来。这个文件分布于C的编译器，并且包含了Windows的一些socket函数。本教程中的一些范例程序，会需要它。

**记住以下几点**：

*  要添加一个预处理定义，你需要打开*Project*菜单，选择*Settings*，然后选择*C/C++*选项卡，在*General*类下，你必须在*Preprocessor Definitions*下的文本框中添加定义。  
 *  要在一个VC++6.0工程中，添加一，个新的库，你必须打开*Project*菜单，选择*Settings*，然后选择*Link*选项卡，然后把新库的名字添加到*Object/Library modules*下的文本框中  
 *  要向VC++6.0中添加一个新的库所在的路径，你必须打开*Tool*菜单，选择*Options*，然后选择*Directories*选项卡，在*Show directories*下拉框中选择*Library files*，并且将新的路径添加到*Directories*中去 
 *  要向VC++6.0中添加一个新的包含文件所在的路径，你必须打开*Tool*菜单，选择*Options*，然后选择*Directories*选项卡，在*Show directories*下拉框中选择*Include files*，并且将新的路径添加到*Directories*中去

![Center][]

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![20130930173906000][]

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## 范例程序 ##

我们一共了一些范例程序来显示WinPcap API的用法。这些程序的源代码，以及编译运行这些代码所需的所有文件，都可以在 [ Developer's Pack][Developer_s Pack]找到。作为教程，在这里，我们提供了浏览器式的代码：这样，在每个函数和变量之间的跳转会比较方便。更多完整的范例程序，请参阅 [ WinPcap 教程][WinPcap].

### Packet Dump ###

这个程序会依据命令行参数，从网络适配器，或是从文件来读取数据包。如果没有提供源，那么程序会显示出所有可用的适配器，你可以选其中一个。当捕获过程开始，程序会打印数据包的时间戳，长度，原始内容。一旦被编译了，那么它将能运行于所有的Win32平台，当然，它也可以被编译成Unix平台的程序。

/*
     * 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 <stdlib.h>
    #include <stdio.h>
    
    //
    // NOTE: remember to include WPCAP and HAVE_REMOTE among your
    // preprocessor definitions.
    //
    
    #include <pcap.h>
    
    #define LINE_LEN 16
    
    main(int argc, char **argv)
    {   
    pcap_if_t *alldevs, *d;
    pcap_t *fp;
    u_int inum, i=0;
    char errbuf[PCAP_ERRBUF_SIZE];
    int res;
    struct pcap_pkthdr *header;
    const u_char *pkt_data;
    
        printf("pktdump_ex: prints the packets of the network using WinPcap.\n");
        printf("   Usage: pktdump_ex [-s source]\n\n"
               "   Examples:\n"
               "      pktdump_ex -s file://c:/temp/file.acp\n"
               "      pktdump_ex -s rpcap://\\Device\\NPF_{C8736017-F3C3-4373-94AC-9A34B7DAD998}\n\n");
    
        if(argc < 3)
        {
    
            printf("\nNo adapter selected: printing the device list:\n");
            /* The user didn't provide a packet source: Retrieve the local device list */
            if (pcap_findalldevs_ex(PCAP_SRC_IF_STRING, NULL, &alldevs, errbuf) == -1)
            {
                fprintf(stderr,"Error in pcap_findalldevs_ex: %s\n", errbuf);
                return -1;
            }
            
            /* Print the list */
            for(d=alldevs; d; d=d->next)
            {
                printf("%d. %s\n    ", ++i, d->name);
    
                if (d->description)
                    printf(" (%s)\n", d->description);
                else
                    printf(" (No description available)\n");
            }
            
            if (i==0)
            {
                fprintf(stderr,"No interfaces found! Exiting.\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");
    
                /* Free the device list */
                pcap_freealldevs(alldevs);
                return -1;
            }
            
            /* Jump to the selected adapter */
            for (d=alldevs, i=0; i< inum-1 ;d=d->next, i++);
            
            /* Open the device */
            if ( (fp= pcap_open(d->name,
                                100 /*snaplen*/,
                                PCAP_OPENFLAG_PROMISCUOUS /*flags*/,
                                20 /*read timeout*/,
                                NULL /* remote authentication */,
                                errbuf)
                                ) == NULL)
            {
                fprintf(stderr,"\nError opening adapter\n");
                return -1;
            }
        }
        else 
        {
            // Do not check for the switch type ('-s')
            if ( (fp= pcap_open(argv[2],
                                100 /*snaplen*/,
                                PCAP_OPENFLAG_PROMISCUOUS /*flags*/,
                                20 /*read timeout*/,
                                NULL /* remote authentication */,
                                errbuf)
                                ) == NULL)
            {
                fprintf(stderr,"\nError opening source: %s\n", errbuf);
                return -1;
            }
        }
    
        /* Read the packets */
        while((res = pcap_next_ex( fp, &header, &pkt_data)) >= 0)
        {
    
            if(res == 0)
                /* Timeout elapsed */
                continue;
    
            /* print pkt timestamp and pkt len */
            printf("%ld:%ld (%ld)\n", header->ts.tv_sec, header->ts.tv_usec, header->len);          
            
            /* Print the packet */
            for (i=1; (i < header->caplen + 1 ) ; i++)
            {
                printf("%.2x ", pkt_data[i-1]);
                if ( (i % LINE_LEN) == 0) printf("\n");
            }
            
            printf("\n\n");     
        }
    
        if(res == -1)
        {
            fprintf(stderr, "Error reading the packets: %s\n", pcap_geterr(fp));
            return -1;
        }
    
        return 0;
    }

### 数据包过滤器 ###

这是一个更加完整的使用libpcap的范例程序，它显示了如何创建和设置过滤器，如何把捕获保存到磁盘。这个程序在Win32和Unix平台下都能编译。Pcap\_filter(pf.exe)是一个通用的数据包过滤程序：它的输入参数有数据包的源(可以是物理接口，或是一个文件)，过滤器和一个输出文件。它会从源获取数据包，并对它们进行过滤，如果它们符合过滤器的要求，就把它们保存到输出文件，直到按下Ctrl+C，或者整个文件处理完毕。Pcap\_filter不但可以根据一个特定的过滤器，来堆处理网络中的数据，而且可以从已经保存过的文件中提取数据包。输入和输出文件的格式都是libpcap兼容的格式，比如，WinDump,tcpdump和其他许多网络工具。

/*
     * 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 <stdlib.h>
    #include <stdio.h>
    
    #include <pcap.h>
    
    #define MAX_PRINT 80
    #define MAX_LINE 16
    
    
    void usage();
    
    
    void main(int argc, char **argv)
    {
    pcap_t *fp;
    char errbuf[PCAP_ERRBUF_SIZE];
    char *source=NULL;
    char *ofilename=NULL;
    char *filter=NULL;
    int i;
    pcap_dumper_t *dumpfile;
    struct bpf_program fcode;
    bpf_u_int32 NetMask;
    int res;
    struct pcap_pkthdr *header;
    const u_char *pkt_data;
    
        if (argc == 1)
        {
            usage();
            return;
        }
    
        for(i=1;i < argc; i+= 2)
        {
    
            switch (argv[i] [1])
            {
                case 's':
                {
                    source=argv[i+1];
                };
                break;
    
                case 'o':
                {
                    ofilename=argv[i+1];
                };
                break;
    
                case 'f':
                {
                    filter=argv[i+1];
                };
                break;
            }
        }
    
        // open a capture from the network
        if (source != NULL)
        {
            if ( (fp= pcap_open(source,
                                1514 /*snaplen*/,
                                PCAP_OPENFLAG_PROMISCUOUS /*flags*/,
                                20 /*read timeout*/,
                                NULL /* remote authentication */,
                                errbuf)
                                ) == NULL)
            {
                fprintf(stderr,"\nUnable to open the adapter.\n");
                return;
            }
        }
    
        else usage();
    
        if (filter != NULL)
        {
            // We should loop through the adapters returned by the pcap_findalldevs_ex()
            // in order to locate the correct one.
            //
            // Let's do things simpler: we suppose to be in a C class network ;-)
            NetMask=0xffffff;
    
            //compile the filter
            if(pcap_compile(fp, &fcode, filter, 1, NetMask) < 0)
            {
                fprintf(stderr,"\nError compiling filter: wrong syntax.\n");
                return;
            }
    
            //set the filter
            if(pcap_setfilter(fp, &fcode)<0)
            {
                fprintf(stderr,"\nError setting the filter\n");
                return;
            }
    
        }
    
        //open the dump file
        if (ofilename != NULL)
        {
            dumpfile= pcap_dump_open(fp, ofilename);
    
            if (dumpfile == NULL)
            {
                fprintf(stderr,"\nError opening output file\n");
                return;
            }
        }
        else usage();
    
        //start the capture
        while((res = pcap_next_ex( fp, &header, &pkt_data)) >= 0)
        {
    
            if(res == 0)
            /* Timeout elapsed */
            continue;
    
            //save the packet on the dump file
            pcap_dump((unsigned char *) dumpfile, header, pkt_data);
    
        }
    }
    
    
    void usage()
    {
    
        printf("\npf - Generic Packet Filter.\n");
        printf("\nUsage:\npf -s source -o output_file_name [-f filter_string]\n\n");
        exit(0);
    }

文章文字出处：[http://www.ferrisxu.com/WinPcap/html/index.html][http_www.ferrisxu.com_WinPcap_html_index.html]

[Center]: /images/20220828/647d5cd75b3b4bc0acf61c3e00ca1ca4.png
[20130930173906000]: /images/20220828/c8f8e4b931054378a381e86a147c0e5b.png
[SouthEast]: /images/20220828/95062f3eba18460197ecd073557bb6e9.png
[Developer_s Pack]: http://www.winpcap.org/install/bin
[WinPcap]: http://www.ferrisxu.com/WinPcap/html/group__wpcap__tut.htm
[http_www.ferrisxu.com_WinPcap_html_index.html]: http://www.ferrisxu.com/WinPcap/html/index.html