Linux之nc命令

关山初度尘未洗，策马扬鞭再奋蹄！这篇文章主要讲述Linux之nc命令相关的知识，希望能为你提供帮助。
Centos安装nc

> yum -y install nc

Ubuntu安装nc

> apt-get install netcat

Mac安装nc

> brew install netcat

命令格式

nc [-hlnruz][-g&
lt;
网关...&
gt;
][-G&
lt;
指向器数目&
gt;
][-i&
lt;
延迟秒数&
gt;
][-o&
lt;
输出文件&
gt;
][-p&
lt;
通信端口&
gt;
]<
br/>
[-s&
lt;
来源位址&
gt;
][-v...][-w&
lt;
超时秒数&
gt;
][主机名称][通信端口...]

命令选项

-g< 网关> 设置路由器跃程通信网关，最多可设置8个。
-G< 指向器数目> 设置来源路由指向器，其数值为4的倍数。
-h 在线帮助。
-i< 延迟秒数> 设置时间间隔，以便传送信息及扫描通信端口。
-l 使用监听模式，管控传入的资料。
-n 直接使用IP地址，而不通过域名服务器。
-o< 输出文件> 指定文件名称，把往来传输的数据以16进制字码倾倒成该文件保存。
-p< 通信端口> 设置本地主机使用的通信端口。
-r 乱数指定本地与远端主机的通信端口。
-s< 来源位址> 设置本地主机送出数据包的IP地址。
-u 使用UDP传输协议。
-v 显示指令执行过程。
-w< 超时秒数> 设置等待连线的时间。
-z 使用0输入/输出模式，只在扫描通信端口时使用。

TCP端口扫描

> nc -v -z-w2rumenz.com20-30 nc: connectx to rumenz.com port 20 (tcp) failed: Connection refused nc: connectx to rumenz.com port 21 (tcp) failed: Connection refused found 0 associations found 1 connections: 1: flags=82< CONNECTED,PREFERRED> outif en0 src 192.168.0.105 port 57984 dst 203.195.152.245 port 22 rank info not available TCP aux info availableConnection to rumenz.com port 22 [tcp/ssh] succeeded! nc: connectx to rumenz.com port 23 (tcp) failed: Connection refused nc: connectx to rumenz.com port 24 (tcp) failed: Connection refused nc: connectx to rumenz.com port 25 (tcp) failed: Connection refused nc: connectx to rumenz.com port 26 (tcp) failed: Connection refused nc: connectx to rumenz.com port 27 (tcp) failed: Connection refused nc: connectx to rumenz.com port 28 (tcp) failed: Connection refused nc: connectx to rumenz.com port 29 (tcp) failed: Connection refused nc: connectx to rumenz.com port 30 (tcp) failed: Connection refused

UDP端口扫描

> nc -v -z -w2 -u rumenz.com 20-25 found 0 associations found 1 connections: 1: flags=82< CONNECTED,PREFERRED> outif (null) src 192.168.0.105 port 63603 dst 203.195.152.245 port 20 rank info not availableConnection to rumenz.com port 20 [udp/ftp-data] succeeded! found 0 associations found 1 connections: 1: flags=82< CONNECTED,PREFERRED> outif (null) src 192.168.0.105 port 51642 dst 203.195.152.245 port 21 rank info not availableConnection to rumenz.com port 21 [udp/ftp] succeeded! found 0 associations found 1 connections: 1: flags=82< CONNECTED,PREFERRED> outif (null) src 192.168.0.105 port 58180 dst 203.195.152.245 port 22 rank info not availableConnection to rumenz.com port 22 [udp/ssh] succeeded! found 0 associations found 1 connections: 1: flags=82< CONNECTED,PREFERRED> outif (null) src 192.168.0.105 port 57409 dst 203.195.152.245 port 23 rank info not availableConnection to rumenz.com port 23 [udp/telnet] succeeded! found 0 associations found 1 connections: 1: flags=82< CONNECTED,PREFERRED> outif (null) src 192.168.0.105 port 59767 dst 203.195.152.245 port 24 rank info not availableConnection to rumenz.com port 24 [udp/*] succeeded! found 0 associations found 1 connections: 1: flags=82< CONNECTED,PREFERRED> outif (null) src 192.168.0.105 port 58696 dst 203.195.152.245 port 25 rank info not availableConnection to rumenz.com port 25 [udp/smtp] succeeded!

扫描指定端口

> nc -v json.im 80 found 0 associations found 1 connections: 1: flags=82< CONNECTED,PREFERRED> outif en0 src 192.168.0.105 port 58683 dst 150.109.147.28 port 80 rank info not available TCP aux info availableConnection to json.im port 80 [tcp/http] succeeded!

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