Abacwaningi abavela ku-NCC Group ubuthakathaka () kuma-chips e-Qualcomm, akuvumela ukuthi unqume okuqukethwe kokhiye bokubethela abayimfihlo abatholakala endaweni engayodwa ye-Qualcomm QSEE (Qualcomm Secure Execution Environment), ngokusekelwe kubuchwepheshe be-ARM TrustZone. Inkinga iziveza ngo I-Snapdragon SoC, esisabalele kuma-smartphones asekelwe ku-platform ye-Android. Izilungiso ezilungisa inkinga sezivele zikhona kusibuyekezo sika-Ephreli se-Android kanye nokukhishwa kwe-firmware entsha yama-chip e-Qualcomm. Kuthathe i-Qualcomm isikhathi esingaphezu konyaka ukulungisa ukulungisa; ulwazi olumayelana nokuba sengozini luqale lwathunyelwa ku-Qualcomm ngoMashi 19, 2018.
Masikhumbule ukuthi ubuchwepheshe be-ARM TrustZone bukuvumela ukuthi udale izindawo ezivikelekile ezihlukaniswa nezingxenyekazi zekhompiyutha ezihlukaniswe ngokuphelele nesistimu eyinhloko futhi zisebenze kuphrosesa ehlukile ebonakalayo usebenzisa isistimu yokusebenza ekhethekile ehlukile. Injongo eyinhloko ye-TrustZone ukuhlinzeka ngokusetshenziswa okukodwa kwamaphrosesa kokhiye bokubethela, ukuqinisekiswa kwe-biometric, idatha yokukhokha nolunye ulwazi oluyimfihlo. Ukusebenzisana ne-OS eyinhloko kwenziwa ngokungaqondile ngokusebenzisa isikhombimsebenzisi sokuthumela. Okhiye bokubethela okuyimfihlo bagcinwa ngaphakathi kwesitolo sokhiye esihlukanisiwe nehadiwe, okuthi, uma sisetshenziswa kahle, singanqanda ukuvuza kwabo uma isistimu engaphansi ifakwa engcupheni.
Ukuba sengozini kungenxa yephutha ekusetshenzisweni kwe-algorithm yokucubungula ijika eliyi-elliptic, okuholele ekuvuzeni kolwazi mayelana nenqubekelaphambili yokucubungula idatha. Abaphenyi basungule indlela yokuhlasela yesiteshi eseceleni evumela ukusebenzisa ukuvuza okungaqondile okukhona ukuze kubuyiselwe okuqukethwe kokhiye abayimfihlo abatholakala ku-hardware-eyodwa. . Ukuvuza kunqunywa ngokusekelwe ekuhlaziyweni komsebenzi webhulokhi yokubikezela yegatsha kanye nezinguquko esikhathini sokufinyelela kudatha esenkumbulweni. Esivivinyweni, abacwaningi babonise ngempumelelo ukutholwa kokhiye abangu-224- kanye no-256-bit ECDSA esitolo esikhethekile se-hardware esisetshenziswa ku-smartphone ye-Nexus 5X. Ukubuyisela ukhiye odingekayo ukukhiqiza amasiginesha edijithali ayizinkulungwane eziyi-12, okuthathe amahora angaphezu kwe-14. Amathuluzi asetshenziselwa ukuhlasela .
Isizathu esiyinhloko senkinga ukwabelana kwezingxenye ze-hardware ezivamile kanye ne-cache yokubala ku-TrustZone nasohlelweni oluyinhloko - ukuhlukaniswa kwenziwa ezingeni lokuhlukaniswa okunengqondo, kodwa kusetshenziswa amayunithi wekhompiyutha avamile kanye neminonjana yokubala nolwazi mayelana negatsha. amakheli afakwa kunqolobane yokucubungula evamile. Ngokusebenzisa indlela ye-Prime+Probe, ngokusekelwe ekuhloleni izinguquko zesikhathi sokufinyelela kulwazi olugcinwe kunqolobane, kungenzeka, ngokubheka ukuba khona kwamaphethini athile kunqolobane, ukuqapha ukugeleza kwedatha nezimpawu zokusetshenziswa kwekhodi ezihambisana nezibalo zamasiginesha edijithali I-TrustZone ngokunemba okuphezulu kakhulu.
Isikhathi esiningi ukwenza isiginesha yedijithali kusetshenziswa okhiye be-ECDSA kuma-chip e-Qualcomm sichithwa kwenziwa imisebenzi yokuphindaphinda ku-loop kusetshenziswa i-vector yokuqalisa engashintshiwe kusiginesha ngayinye (). Uma umhlaseli ekwazi ukuthola okungenani izingcezu ezimbalwa ngolwazi mayelana nale vector, kuyenzeka enze ukuhlasela ukuze athole wonke ukhiye oyimfihlo ngokulandelana kwawo.
Endabeni ye-Qualcomm, izindawo ezimbili lapho ulwazi olunjalo luye lwaputshuzwa khona ziphawulwe ku-algorithm yokuphindaphinda: lapho kwenziwa imisebenzi yokubheka kumathebula kanye nekhodi yokubuyiswa kwedatha enemibandela ngokusekelwe enanini lokugcina ku-vector "nonce". Naphezu kweqiniso lokuthi ikhodi ye-Qualcomm iqukethe izinyathelo zokulwisana nokuvuza kolwazi ngamashaneli ezinkampani zangaphandle, indlela yokuhlasela ethuthukisiwe ikuvumela ukuba udlule lezi zinyathelo futhi unqume izingcezu ezimbalwa zevelu ethi "nonce", ezanele ukubuyisela okhiye abangu-256-bit ECDSA.
Source: opennet.ru