一、介绍:
netcat是一个通过TCP/UDP在网络中进行读写数据工具(命令),被称为“瑞士军刀”,主要用于调试领域、传输领域甚至黑客攻击领域。利用该工具,可以将网络中一端的数据完整的发送至另一台主机终端显示或存储,常见的应用为文件传输、与好友即时通信、传输流媒体或者作为用来验证服务器的独立的客户端。当然,也可以在脚本中使用该工具。
二、Linux上安装:
- 第一种方式:
yum -y install nc
yum remove nmap-ncat.x86_64(删除)
- 第二种方式:
下载rpm包,在Linux上安装就好
三、简单使用
命令行参数介绍:
-U, --unixsock Use Unix domain sockets only
-C, --crlf Use CRLF for EOL sequence
-c, --sh-exec <command> Executes the given command via /bin/sh
-e, --exec <command> Executes the given command
--lua-exec <filename> Executes the given Lua script
-g hop1[,hop2,...] Loose source routing hop points (8 max)
-G <n> Loose source routing hop pointer (4, 8, 12, ...)
-m, --max-conns <n> Maximum <n> simultaneous connections
-h, --help Display this help screen
-d, --delay <time> Wait between read/writes
-o, --output <filename> Dump session data to a file
-x, --hex-dump <filename> Dump session data as hex to a file
-i, --idle-timeout <time> Idle read/write timeout
-p, --source-port port Specify source port to use
-s, --source addr Specify source address to use (doesn't affect -l)
-l, --listen Bind and listen for incoming connections
-k, --keep-open Accept multiple connections in listen mode
-n, --nodns Do not resolve hostnames via DNS
-t, --telnet Answer Telnet negotiations
-u, --udp Use UDP instead of default TCP
--sctp Use SCTP instead of default TCP
-v, --verbose Set verbosity level (can be used several times)
-w, --wait <time> Connect timeout
-z Zero-I/O mode, report connection status only
--append-output Append rather than clobber specified output files
--send-only Only send data, ignoring received; quit on EOF
--recv-only Only receive data, never send anything
--allow Allow only given hosts to connect to Ncat
--allowfile A file of hosts allowed to connect to Ncat
--deny Deny given hosts from connecting to Ncat
--denyfile A file of hosts denied from connecting to Ncat
--broker Enable Ncat's connection brokering mode
--chat Start a simple Ncat chat server
--proxy <addr[:port]> Specify address of host to proxy through
--proxy-type <type> Specify proxy type ("http" or "socks4" or "socks5")
--proxy-auth <auth> Authenticate with HTTP or SOCKS proxy server
--ssl Connect or listen with SSL
--ssl-cert Specify SSL certificate file (PEM) for listening
--ssl-key Specify SSL private key (PEM) for listening
--ssl-verify Verify trust and domain name of certificates
--ssl-trustfile PEM file containing trusted SSL certificates
--ssl-ciphers Cipherlist containing SSL ciphers to use
--version Display Ncat's version information and exit
举一个简单地小例子
nc 可以在两台机器之间相互传递信息,首先需要有一台机器进行监听一个端口,另一台以连接的方式去连接其指定的端口,这样两台机器之间建立了通信后,相互之间可以传输信息。(为了区分,一个机器发送字母,一个机器发送数字,端口号任意指定)