Ndị na-eme nchọpụta sitere na Mahadum Sayensị Sayensị na Nkà na Ụzụ Ndị Nnwere Onwe Ndị Mmadụ, Mahadum Mba nke Singapore na ETH Zurich ewepụtala usoro ọhụrụ nke ịwakpo ndị dịpụrụ adịpụ enclaves Intel SGX (Software Guard eXtensions). A na-akpọ ọgụ a SmashEx ma kpatara nsogbu na ịlọghachite mgbe ị na-ejikwa ọnọdụ ewepu n'oge arụ ọrụ nke ngwa oge maka Intel SGX. Usoro mbuso agha a na-atụ aro na-eme ka o kwe omume, ọ bụrụ na ị nwere njikwa sistemụ arụmọrụ, chọpụta data nzuzo dị na ogige ahụ, ma ọ bụ hazie nnomi koodu gị n'ime ebe nchekwa nchekwa na mkpochapụ ya.
A kwadowo ụdị ihe nleba anya maka enclaves nwere oge ọsọ dabere na Intel SGX SDK (CVE-2021-0186) na Microsoft Open Enclave (CVE-2021-33767). N'okwu nke mbụ, e gosipụtara ike iwepụta igodo RSA ejiri na sava weebụ maka HTTPS, na nke abụọ, ọ ga-ekwe omume ịchọpụta ọdịnaya nke cURL uru nwetara na-agba ọsọ n'ime oghere. A kọwalarị ihe ọghọm ahụ na mmemme na mwepụta nke Intel SGX SDK 2.13 na Open Enclave 0.17.1. Na mgbakwunye na Intel SGX SDK na Microsoft Open Enclave, adịghị ike ahụ na-apụtakwa na Google Asylo SDK, EdgelessRT, Apache Teaclave, Rust SGX SDK, SGX-LKL, CoSMIX na Veracruz.
Ka anyị cheta na teknụzụ SGX (Software Guard Extensions) pụtara na ọgbọ nke isii Intel Core processors (Skylake) ma na-enye usoro ntuziaka nke na-enye ohere ka ngwa ọkwa onye ọrụ kenye ebe nchekwa mechiri emechi - enclaves, ọdịnaya nke enweghị ike ịgụ na gbanwetụrụ ọbụna site na kernel na koodu egburu na ring0, SMM na ụdị VMM. Ọ gaghị ekwe omume ịnyefe njikwa na koodu na enclave site na iji ọrụ ịgba ọsọ ọdịnala na mmegharị ya na ndekọ na nchịkọta - a na-eji ntuziaka ọhụrụ emepụtara EENTER, EEXIT na ERESUME iji nyefee njikwa na enclave, nke na-eme nlele ikike. N'okwu a, koodu etinyere na enclave nwere ike iji ụzọ ịkpọ oku oge gboo iji nweta ọrụ n'ime oghere yana ntuziaka pụrụ iche ịkpọ ọrụ mpụga. A na-eji enclave ebe nchekwa kpuchido megide mwakpo ngwaike dị ka ijikọ na modul DRAM.
Nsogbu a bụ na teknụzụ SGX na-enye ohere ka sistemu arụ ọrụ kagbuo ihe mgbochi site na ịtụfu ihe ewepu ngwaike, yana nchikota anaghị emejuputa usoro izizi maka ijikwa ihe ndị dị otú ahụ n'ụzọ atọ. N'adịghị ka kernel sistemụ na ngwa mgbe niile, koodu n'ime enclaves enweghị ohere ịnweta primitives maka ịhazi omume atọm mgbe ị na-ejikwa ihe ndị a tụfuru asynchronously. Na-enweghị primitives atọm akọwapụtara, enwere ike ịkwụsị enclave ahụ n'oge ọ bụla wee laghachi na mmezu, ọbụlagodi mgbe enclave na-eme akụkụ dị oke egwu ma nọ n'ọnọdụ enweghị nchekwa (dịka ọmụmaatụ, mgbe echekwaghị / weghachite ndekọ CPU).
Maka ịrụ ọrụ nkịtị, teknụzụ SGX na-enye ohere ka akwụsị ogbugbu nke enclave site na ewepu ngwaike nhazi. Njirimara a na-enye ohere gburugburu oge ịgba ọsọ iji mejuputa njikwa ewepu intra-enclave ma ọ bụ nhazi akara, mana ọ nwekwara ike bute mperi mbanye. Mwakpo SmashEx gbadoro ụkwụ na iji ntụpọ dị na SDK n'ihi nke anaghị edozi ọnọdụ nke ịkpọgharị onye na-ahụ maka wepụrụ nke ọma. Ọ dị mkpa na iji na-erigbu adịghị ike ahụ, onye na-awakpo ahụ ga-enwe ike ịkwụsị njedebe nke mkpochapụ ahụ, ya bụ. ga-achịkwa ọrụ nke usoro gburugburu ebe obibi.
Mgbe ọ tụchara ihe dị iche, onye na-awakpo ahụ na-enweta obere windo oge nke enwere ike igbochi eri ogbugbu site na iji usoro ntinye ntinye. Karịsịa, ọ bụrụ na ị nwere ike ịbanye na sistemụ (gburugburu ebe dịpụrụ adịpụ), ị nwere ike ịmepụta ihe ọhụrụ ozugbo emechara ntuziaka ntinye enclave (EENTER), nke ga-alọghachi njikwa na sistemụ ahụ na ọkwa mgbe nhazi nchịkọta maka enclave emechabeghị, ebe echekwara steeti ndekọ CPU.
Usoro ahụ nwere ike weghachite njikwa azụ na enclave, mana ebe ọ bụ na ahazighị nchịkọta nke enclave n'oge nkwụsịtụ ahụ, ihe mkpuchi ahụ ga-eme ya na nchịkọta nke bi na ebe nchekwa sistemụ, nke enwere ike iji mee ihe omume nlọghachi (ROP). Usoro nrigbu. Oriented Programming). Mgbe ị na-eji usoro ROP, onye na-awakpo ahụ anaghị anwa itinye koodu ya na ebe nchekwa, kama ọ na-arụ ọrụ na mpempe akwụkwọ ntuziaka dị na ụlọ akwụkwọ ndị a na-ebu ibu, na-ejedebe na ntuziaka nlọghachi (dịka iwu, ndị a bụ njedebe nke ọrụ ụlọ akwụkwọ) . Ọrụ nke nrigbu na-agbadata iji wuo usoro oku na ngọngọ ndị yiri ya ("ngwa") iji nweta ọrụ achọrọ.
isi: opennet.ru