
iptables

iptables anedi oka user-space utility programme, idhi system administratornu linux kernell firewall yokka aipi packett filter niyamaalanu configure cheyadaaniki anumatistundi, idhi ververu nett filter modulesga amalu cheyabadutundi. filterlu vividha pattikalalo nirvahinchabadataayi, ivi network traaphik pyaaketlanu elaa chikitsa cheyaalo niyamaala golusulanu kaligi untaayi. prastutam vividha kernell modules mariyu prograamlu ververu protocolla kosam upayoginchabadutunnaayi; "iptables" anedi ipv4kii, "ip6tables" anedi ipv6kii, "arptables" anedi arpkii, mariyu "eetharnet framelaku" vartistundi.
iptables panicheyadaaniki unnata adhikaralu avasaram mariyu viniyogadaaru muulam dwara amalu cheyabadaali, lekapothe adhi panicheyadu. chaalaa linux vyavasthalalo, iptables daani myaan pageelalo install cheyabadi, document cheyabadi, install chesinappudu coc _ 1 upayoginchi teravavacchu. idhi coque _ 2loe kooda kanugonabadavacchu, conny iptables anedi "essential binary" kante seva laaga untundi kabatti, ishtapade sthaanam migili untundi.
iptables" anae padaanni saadhaaranamgaa kernell-sthaayi bhaagaalanu kalupukoni suuchimchadaaniki kooda upayogistaaru. "x _ tables" anedi naalugu maadyuulla dwara upayoginche shared code bhaganni mosukelle kernell module paeru, idhi podigimpula kosam upayoginche api nii kooda andistundi; tadanantaram, mottam firewall (v4, v6, arp, mariyu eb) nirmaanaanni suuchimchadaaniki "xtables" ekkuva ledhaa takkuva upayoginchabadutundi.
iptables aipchainlanu adhigaminchaayi; mariyu iptables yokka varasudu enftables, idhi 19 janavari 2014naa vidudalaindi mariyu kernell version 3.13loe linux kernell mainlinelo vileenam cheyabadindi.
sameeksha.
pyaaketla chikitsa kosam "niyamaala" golusulanu kaligi unna "pattikalu" nirvachinchadaaniki vyavastha nirvaahakudini iptables anumatistundi. prati table vaerae rakamaina packett prosessingtho anubandhinchabadindi. pyaaketlanu golusulalo niyamaalanu kramam tappakunda daatadam dwara proses chestaaru. golusuloni oka niyamam oka gottaniki kaaranamavutundi ledhaa maroka golusuku dookavacchu, mariyu idhi kaavalasina sthaayi goodu kattadaniki punaraavrutam cheyavachu. (oka jump anedi oka "coll" laantidi, antey.ii. nundi dookina point gurthunchukobadutundi.) computer nundi vachhe ledhaa vadili vellae prati network packett kaneesam oka golusunu daatutundi.
packett yokka muulam adhi modata yea golusunu daatutundo nirnayistundi. aidu "mundhe nirvachinchina golusulu" unnaayi (andubaatulo unna aidu nett filter huklaku mapping), ayithe oka table anni golusulanu kaligi undakapovachhu. mundugaa nirvachinchina golusulu oka "palasi" nii kaligi untaayi, udaaharanaku drop, idhi golusu chivaraku cherukunnatlayithe pyaaketku vartinchabadutundi. system administrator korukunnanni itara golusulanu srushtinchavachu. eee golusulaku etuvanti vidhanam ledhu; oka packett golusu chivaraku cherukunnatlayithe adhi daanini piliche golusuku tirigi ivvabadutundi. golusu khaliga undavacchu.
oka golusu swayamgaa ledhu; adhi oka "table" kii chendinadi. moodu pattikalu unnaih "nott", "filter" mariyu "mangle". -t" empikaku mundu unte tappa, oka coque _ 9 command defaultga "filter" tableku sambandhinchinadi. udaaharanaku, konni golusulu mariyu vaati niyamaalanu choopinche command coque _ 10, coque _ 11kii samanam. table "nott" golusulanu choopinchadaaniki, coque _ 12 kamaandnu upayoginchandi.
golusuloni prati niyamam yea pyaaketlatho saripolutundo vivaristundi. idhi "lakshyam" (podigimpula kosam upayoginchabadutundi) ledhaa "teerpu" (antarnirmita nirnayaalalo okati) kooda kaligi undavacchu. oka packett oka golusunu daatutunnappudu, prati niyamam pariseelinchabadutundi. oka niyamam pyaakettoe saripolakapothe, packett tadupari nibandhanaku pampabadutundi. oka niyamam pyaakettoe saripolithe, niyamam lakshyam/teerpu dwara suuchimchabadina charyanu teesukuntundi, dheeni phalitamgaa packett golusu venta konasaagadaaniki anumatinchabadavacchu ledhaa anumatinchabadakapovachhu. matchlu niyamaalalo pedda bhaganni kaligi untaayi, endukante avi sharatula pyaaketlanu kaligi untaayi, vaati kosam pareekshinchabadataayi. ivi ii maadirigaa osi namuunaalooni yea porakaina jaragavacchu.zii. coque _ 13 mariyu coque _ 14 paaraamitulu, mariyu coque _ 15 vanti protocol-swatantra matchlu kooda unnaayi.
packett golusu gundaa velladam konasaagistundi
lakshyalu kooda coque 16 (coque 21 modules ilaa chestaayi) ledhaa coque 17 (ii.zii. coque _ 23 module), conny coque _ 24 (e.zii. tadupari niyamanni konasaaginchadaaniki lakshyam/teerpu assalu perkonabadaledu kabatti, coque _ 25 module; coque _ 24 anedi antargata paeru).
viniyogadaarula sthala viniyogaalu.
mundu bhagalu.
niyamaalanu erpaatu cheyadaaniki veelugaa iptables kosam aneka moodava party software applications unnaayi. vachana ledhaa graphical paddhatiloo front-ends viniyogadaarulanu saadhaarana niyamaalanu click-generate cheyadaaniki anumatistaayi; scriptlu saadhaaranamgaa shell scriptlanu suuchistaayi (conny itara scripting bhashalu kooda saadhyame) avi iptables ledhaa (vaegamgaa) coc _ 27 anie pilavabade mundugaa nirvachinchina niyamaala samititoe, ledhaa saadhaarana aakruteekarana file sahayamtho template nundi vistarinchina niyamaalu. linux pampinheelu saadhaaranamgaa templetlanu upayoginche taruvaati pathakaanni upayogistaayi. atuvanti template-aadhaarita vidhanam aacharanatmakamgaa ruul generator yokka parimita roopam, mariyu atuvanti generatorlu kooda swatantra paddhatiloo unnaayi, udaaharanaku, php web paejeelugaa.
atuvanti front-ends, generatorlu mariyu scriptlu tarachugaa vaati antarnirmita template vyavasthala dwara parimitam cheyabadataayi mariyu ikkada templatelu viniyogadaaru-nirvachinchina niyamaalaku pratyaamnaaya spotlanu andistaayi. alaage, utpatti cheyabadina niyamaalu saadhaaranamgaa viniyogadaaru korukunna nirdishta firewalling prabhaavaaniki anukuulamainavi kaavu, endukante alaa cheyadam valla devalaparku nirvahana kharchu perige avakaasam undhi. iptables nuu sahetukamgaa ardham chesukunna mariyu vaari niyamaalanu optimize cheyalanukune viniyogadaarulu vaari swantha niyamaalanu nirminchukovaalani salaha istaaru.

