An ƙare LCP da takwaransa a kan PPTP: fara kunna MPPE

Haɗin yana tabbatar da kansa, abokin ciniki yana ba da rahoton an haɗa shi, kuma bayan daƙiƙa ɗaya log ɗin yana rufewa da LCP wanda takwaransa ya ƙare. Wannan layin ya fito ne daga tattaunawar PPP a cikin ramin GRE, don haka hanyar jigilar ta riga ta yi aiki kuma ɓangarorin biyu ba su yarda da zaɓuɓɓukan haɗin ba. Kalmomin sirri da adiresoshin uwar garke yawanci ba su da laifi a nan. Manufar ɓoye bayanai ita ce abu na farko da za a kwatanta, kuma a Linux fayil ɗin takwaransa na pppd shine wuri na farko da za a duba.

Me gazawar LCP ke faɗi game da matakin PPP

PPTP yana nannade PPP cikin GRE: haɗin sarrafawa na TCP 1723 yana kafa kira, GRE yana ɗaukar kaya, sannan LCP yana tattaunawa kan zaɓuɓɓuka kamar ka'idar tabbatarwa, matsewa da MPPE. Takwaransa yana ƙare LCP idan wani zaɓi da ake buƙata bai zama karɓaɓɓe a gefensa ba. Log ɗin da musayar CHAP ko MSCHAPv2 ke kammala kuma LCP ke ƙarewa nan da nan bayan haka ƙin manufa ne, ba gazawar isa ba. Idan ramin bai kai ga tattaunawa kwata-kwata ba, bincika pppd da plugin ɗinsa kafin karanta layin LCP.

Sharuddan farko guda biyu ana mantawa da su cikin sauƙi. Fayil ɗin binary na pppd dole ya wanzu, kuma plugin ɗin PPTP da aka ambata a fayil ɗin takwaransa dole a shigar da shi; kunshin da ya ɓace yana ƙare kiran kafin a tattauna kowane zaɓi.

Kunna MPPE a ɓangaren da yake buƙatarsa

Babbar shawara ita ce wane ɓangare ne ya mallaki manufar ɓoye bayanai. Abokin ciniki na iya ba da MPPE, buƙata ko ƙi shi, kuma uwar garke tana yin irin wannan zaɓi. Idan duka biyu suna buƙatarsa haɗin yana tashi; idan ɗaya ya buƙata ɗayan kuma ya ƙi, LCP yana ƙarewa.

pty "pptp vpn.example.net --nolaunchpppd"
name alice
remotename PPTP
require-mppe-128

Loda module ɗin da modprobe ppp_mppe kafin yin kira, domin ba tare da shi require-mppe-128 yana gazawa ba. A Windows daidaitaccen sarrafawa shine shafin tsaro na shigarwar VPN, inda dole a gaya wa abokin ciniki ya buƙaci ɓoye bayanai maimakon karɓar duk abin da uwar garke ta bayar. Idan uwar garke har yanzu tana ƙare LCP, tambayi ma'aikacinta ko MPPE wajibi ne, na zaɓi ko an kashe shi, domin abokin ciniki ba zai iya tattaunawa kan kariyar da uwar garke ta ƙi ba. Kashe ɓoye bayanai don saƙon ya ɓace hanya ce mara kyau: yana cire kariyar da wannan ka'ida take da ita.

Ajiye fayil ɗin takwaransa mai aiki kafin gyara shi. Layin require-mppe da aka rubuta ba daidai ba yana sake haifar da wannan gazawar LCP ta gama gari kuma yana mayar da kai farkon.

Karanta log ɗin pppd kanta maimakon applet ɗin

Applets na tebur suna nuna cirewar haɗin kuma suna ɓoye dalilin, don haka karanta labarin daemon ɗin game da ƙoƙari ɗaya. A tsarin systemd saƙon yana shiga journal; tsofaffin saitin suna rubutu cikin fayilolin log na gargajiya.

journalctl --since "10 min ago" | grep -i -E "pppd|lcp|mppe"
tail -n 50 /var/log/syslog

Bincika a cikin taga kusa da kira ɗaya maimakon kwana ɗaya na sake haɗawa, don zaɓin da aka ƙi ya zama mai sauƙin gani. pppd yawanci yana ambaton zaɓin da amsar takwaransa, wanda ke gaya maka ko za ka canza shawararka ko ka nemi ɓangaren uwar garke ya sassauta bukatarsa. Riƙe ƙoƙarin da tambarin lokaci, domin kwatanta log biyu yana da amfani ne kawai idan ka san waɗanne layuka suke cikin wane kira. Idan babu musayar LCP kwata-kwata, kuskuren yana baya a cikin sarƙar kuma MPPE ba shi ne wanda ake zargi ba.

Riƙe gyaran a duk sake haɗawa: sunayen hook da MTU

Da zarar haɗin ya tsaya, bayanai biyu ne ke yanke shawara ko zai jure sake haɗawa. Hooks suna cikin /etc/ppp/ip-up.d da /etc/network/if-up.d, kuma dukkanin manyan fayilolin biyu run-parts ne ke sarrafa su, wanda matatar sunan fayil ɗinsa ke ƙin duk abin da ke ɗauke da aya. Don haka ana tsallake script mai suna set-pptp.sh, yayin da ake aiwatar da set-pptp. Duba sunan kafin gyara abubuwan cikin script ɗin, sannan saita ƙaramin MTU daga cikin wannan hook don kowane sabon ppp interface ya gaji shi ba tare da umarnin hannu ba.

run-parts --test /etc/ppp/ip-up.d
ip link set dev ppp0 mtu 1200

Don kawo ƙarshen zama da gangan, yi niyya ga pid ɗin da pppd ya rubuta maimakon daidaita sunayen tsari, domin kashe duk abin da ke ɗauke da ppp yana rushe haɗin da ba su da alaƙa. PPTP ya tsufa kuma MS-CHAPv2 rauni ne, don haka ɗauki waɗannan binciken a matsayin kulawa ga haɗin da dole ya ci gaba da aiki, ba dalilin tura PPTP a kowane sabon wuri ba.