8 Netcat (nc) Umurni tare da Misalai
Netcat (ko nc a takaice) kayan aiki ne masu sauƙin ƙarfi kuma masu ƙarfi na sadarwar da ake amfani dasu don aiwatar da kowane aiki a cikin Linux dangane da TCP, UDP, ko UNIX-soket.
Ana iya amfani da Netcat don binciken tashar jiragen ruwa, juyar da tashar jiragen ruwa, a matsayin mai sauraren tashar jiragen ruwa (don haɗin mai shigowa); Hakanan za'a iya amfani dashi don buɗe haɗin haɗin nesa da sauran abubuwa da yawa. Bayan haka, zaku iya amfani da shi azaman bangon baya don samun damar zuwa sabar manufa.
A cikin wannan labarin, zamuyi bayanin umarnin amfani da Netcat tare da misalai.
Yadda ake Shigar da amfani da Netcat a cikin Linux
Don shigar da kunshin netcat akan tsarinku, yi amfani da mai sarrafa kunshin tsoho don rarraba Linux.
$ yum install nc [On CentOS/RHEL] $ dnf install nc [On Fedora 22+ and RHEL 8] $ sudo apt-get install Netcat [On Debian/Ubuntu]
Da zarar an shigar da kunshin yanar gizo, zaku iya ci gaba don koyon yadda ake amfani da umarnin netcat a cikin misalai masu zuwa.
Ana iya amfani da Netcat don binciken tashar jiragen ruwa: don sanin waɗanne kofofin buɗewa suke kuma suna aiki a kan na'urar da ake so. Zai iya bincika guda ɗaya ko mahara ko kewayon buɗe tashoshin jiragen ruwa.
Ga misali, zabin -z saita nc don kawai bincika scanning daemons, ba tare da aikawa da wani data gare su ba. Zaɓin -v yana ba da damar yanayin magana kuma -w yana ƙayyade lokacin hutu don haɗi wanda ba za a iya kafa shi ba.
$ nc -v -w 2 z 192.168.56.1 22 #scan a single port OR $ nc -v -w 2 z 192.168.56.1 22 80 #scan multiple ports OR $ nc -v -w 2 z 192.168.56.1 20-25 #scan range of ports
Netcat yana ba ka damar canja wurin fayiloli tsakanin kwamfutocin Linux biyu ko sabobin kuma duka waɗannan tsarin dole ne a shigar da nc.
Misali, don kwafa fayil ɗin hoto na ISO daga wannan komputa zuwa wata kuma saka idanu kan ci gaban canja wuri (ta amfani da pv utility), gudanar da umarni mai zuwa akan kwamfutar mai aikawa/uwar garken (inda fayil ɗin ISO ɗin yake).
Wannan zai gudana nc a yanayin sauraro ( -l tuta) akan tashar 3000.
$ tar -zcf - debian-10.0.0-amd64-xfce-CD-1.iso | pv | nc -l -p 3000 -q 5
Kuma akan kwamfutar mai karɓar/kwastomomi, gudanar da wannan umarni don samun fayil ɗin.
$ nc 192.168.1.4 3000 | pv | tar -zxf -
Hakanan zaka iya amfani da Netcat don ƙirƙirar sauƙin uwar garken saƙon saƙo na layi-sauri. Kamar yadda yake a misalin amfani na baya, dole ne a shigar da nc akan duka tsarin da aka yi amfani dashi don ɗakin hira.
A kan wani tsarin, gudanar da wannan umarni don kirkirar uwar garken tattaunawa a tashar 5000.
$ nc -l -vv -p 5000
A wani tsarin, gudanar da wannan umarni don ƙaddamar da zaman tattaunawa zuwa na'ura inda sabar saƙon take gudana.
$ nc 192.168.56.1 5000
Shafin zaɓi na -l na umarnin nc da aka yi amfani da shi don ƙirƙirar sabar yanar gizo mara tsaro, don hidiman fayilolin gidan yanar gizo masu tsaye don dalilan koyo. Don nuna wannan, ƙirƙirar fayil .html kamar yadda aka nuna.
$ vim index.html
Sanya layukan HTML masu zuwa a cikin fayil din.
<html>
<head>
<title>Test Page</title>
</head>
<body>
<p>Serving this file using Netcat Basic HTTP server!</p>
</body>
</html>
Adana canje-canje a cikin fayil ɗin kuma fita.
Sannan yi amfani da fayil ɗin da ke sama akan HTTP ta hanyar aiwatar da umarni mai zuwa, wanda zai ba uwar garken HTTP damar ci gaba da gudana.
$ while : ; do ( echo -ne "HTTP/1.1 200 OK\r\n" ; cat index.html; ) | nc -l -p 8080 ; done
Sannan buɗe burauzar yanar gizo kuma za a iya samun damar abun ciki ta amfani da adireshin da ke gaba.
http://localhost:8080 OR http://SERVER_IP:8080
Lura cewa zaka iya dakatar da sabar Netcat HTTP ta latsa [Ctrl + C] .
Wani amfani mai amfani na Netcat shine warware matsalar matsalolin haɗin sabar. Anan, zaku iya amfani da Netcat don tabbatar da irin bayanan da sabar ke aikawa dangane da umarnin da abokin ciniki ya bayar.
Umurnin da ke gaba ya dawo da shafin gida na misali.com.
$ printf "GET / HTTP/1.0\r\n\r\n" | nc text.example.com 80
Fitowar umarnin da ke sama ya haɗa da kanun labarai wanda aka aika ta sabar yanar gizo wanda za a iya amfani da shi don dalilai na matsala.
Hakanan zaka iya amfani da Netcat don samun bankunan tashar jiragen ruwa. A wannan yanayin, zai gaya muku abin da sabis yake gudana a bayan wani tashar jirgin ruwa. Misali don sanin wane irin sabis ne yake gudana a bayan tashar jiragen ruwa 22 a kan takamaiman sabar, gudanar da umarnin mai zuwa (maye gurbin 192.168.56.110 tare da adireshin IP ɗin uwar garke mai manufa). Tutar -n na nufin musaki DNS ko neman sabis.
$ nc -v -n 192.168.56.110 80
Netcat yana tallafawa ƙirƙirar ɗakunan rafi na UNIX-yankin. Umurnin mai zuwa zai ƙirƙiri kuma ya saurara akan butar rafin UNIX-domain.
$ nc -lU /var/tmp/mysocket & $ ss -lpn | grep "/var/tmp/"
Hakanan zaka iya gudanar da Netcat azaman bayan fage. Koyaya, wannan yana buƙatar ƙarin aiki. Idan an shigar da Netcat a kan sabar da aka yi niyya, za ka iya amfani da ita don ƙirƙirar ƙofar baya, don samun umarnin gaggawa daga nesa.
Don yin bayan gida kana buƙatar Netcat don saurara akan tashar da aka zaɓa (misali tashar jiragen ruwa 3001) a kan sabar manufa sannan kuma za ka iya haɗawa zuwa wannan tashar daga mashin ɗinka kamar haka.
Wannan shine umarnin da aka tsara don gudana akan sabar nesa inda zaɓin -d ya dakatar da karatu daga stdin, kuma -e yana ƙayyade umarnin da zai gudana akan tsarin manufa.
$ nc -L -p 3001 -d -e cmd.exe
A ƙarshe amma ba mafi ƙaranci ba, ana iya amfani da Netcat azaman wakili don ayyuka/ladabi daban-daban gami da HTTP, SSH, da ƙari mai yawa. Don ƙarin bayani, duba shafin mutum.
$ man nc
A cikin wannan labarin, mun bayyana misalai na amfani da umarnin Netcat guda 8 masu amfani. Idan kun san wani yanayin amfani da shi, raba tare da mu ta hanyar fom ɗin da ke ƙasa. Kuna iya yin tambaya kuma.