ngrep是一个功能强大的网络包分析工具。它可以实时捕获和分析网络数据包,并且被广泛应用于网络调试、安全审计和流量分析等多个领域。本文将详细介绍ngrep命令的用法,包括基本语法、常用选项和高级用法。
ngrep的基本语法如下:
ngrep [选项] PATTERN [DEVICE]
PATTERN是用于匹配网络数据包的正则表达式,DEVICE是要监听的网络设备,如eth0、lo等。
指定数据包的深度,默认为2。只有当数据包的深度大于等于指定值时,ngrep才会显示该数据包。
静默模式,不输出任何信息。
不解析主机名和端口号,直接显示IP地址和端口号。
在捕获的数据包中添加时间戳。
在捕获的数据包中添加应用层协议信息。
设置捕获数据包的超时时间,单位为秒。
设置关键字过滤,只显示包含关键字的数据包。
设置HTTP头过滤,只显示包含指定HTTP头的数据包。
设置IP过滤,只显示来自指定IP的数据包。
设置链路层过滤,只显示来自指定MAC地址的数据包。
ngrep 'tcp'
ngrep 'udp'
ngrep 'icmp'
ngrep 'port 80'
ngrep 'ip 192.168.1.1'
ngrep 'ether 00:11:22:33:44:55'
sudo ngrep 'tcp' eth0 d 2 q n t A W 10 K "GET" H "Host: www.example.com" I "192.168.1.1" L "00:11:22:33:44:55"
sudo ngrep 'icmp and (icmp[0] == 8 or icmp[0] == 0)' q n t W 10 K "Echo Request" I "192.168.1.1" L "00:11:22:33:44:55"
答:可以使用k选项来过滤掉重复的数据包。以下命令只显示第一个匹配的数据包:
sudo ngrep 'pattern' k q n t W 10 K "keyword" I "ip" L "mac" DEVICE_NAME | head -n 1 > output.txt && tail -n +2 output.txt > /dev/null & disown %+; cat output.txt; rm output.txt; kill %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; rm output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; rm output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; rm output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; rm output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; rm output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; rm output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; rm output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; rm output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; rm output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; rm output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; rm output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; rm output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; rm output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; rm output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; rm output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; rm output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; rm output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; rm output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; rm output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt; rm output.txt; exit 0; disown %+; wait %+; echo "Process finished." >> output.txt; cat output.txt
希望本文能够帮助您更好地理解和使用ngrep命令。如果您对网络包分析和数据包捕获感兴趣,可以继续学习Wireshark等相关工具。同时,如果您有任何问题或想法,请在评论区留言,我们会尽快回复。感谢您的观看和支持!
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