Увод
Incryptanalysis,aknownplaintextattackisanattackmode,whichmeansthattheattackerhasmasteredacertainsectionofplaintextxandthecorrespondingciphertexty.
Inallcryptanalysis,itisassumedthattheattackerknowsthecryptosystembeingused.ThisassumptioniscalledtheKockhoffhypothesis.Theknownplaintextattackalsoassumesthattheattackercanobtainpartoftheplaintextandthecorrespondingciphertext,suchasinterceptingthefirstpartoftheinformation,andobtainingtheencryptionmethodthroughthistypeofattack,soastofacilitatethecrackingofthelatterpartoftheciphertext.
Hillciphersrelyononlyciphertextattacks,whicharedifficulttocrack,butareeasiertobreakthroughknownplaintextattacks.
Релатедтермс
Ципхертектонлиаттацк
Скиптонавигатионандсеарцх
Incryptographyorcryptanalysis,Ципхертектонлиаттацкisanattackmodethatreferstoanattackwhenonlytheencryptedtext(ie,ciphertext)isknown.Thisschemecanbeusedtoattacksymmetriccryptosystemsandasymmetriccryptosystemsatthesametime.
Theciphertext-onlyattackhopestoachieveseveralgoals,arrangedaccordingtothedegreeofsuccess:
Гет сомеинформатион ин тхеоригиналплаинтект.
Геттхеоригиналплаинтект.
Леарнтхекеифордецриптион.
Theexhaustivemethodisaciphertext-onlyattack,buttheexhaustivemethodisgenerallyconsideredwhendesigningthealgorithm.
Селецтплаинтектаттацк
Скиптонавигатионандјумптосеарцх
Incryptographyorcryptanalysis,selectplaintextattackreferstoItisamodeofattack.Theattackerhasaccesstotheencryptionmachineandcanconstructciphertextcorrespondingtoanyplaintext.
Inthisattackmode,theattackercanarbitrarilyselectacertainamountofplaintextinadvance,encrypttheattackedencryptionalgorithm,andobtainthecorrespondingciphertext.Theattacker'sgoalistoobtainsomeinformationabouttheencryptionalgorithmthroughthisprocess,sothattheattackercanmoreeffectivelycracktheinformationencryptedbythesameencryptionalgorithm(andrelatedkeys)inthefuture.Intheworstcase,theattackercandirectlyobtainthekeyfordecryption.
Thisattackmodedoesnotseemrealisticatfirst,becauseitishardtoimaginethatanattackercanchooseanyinformationandasktheencryptionsystemtoencryptit.However,inpublickeycryptography,thisisaveryrealisticmodel.Thisisbecauseinthepublickeycryptographicscheme,theencryptionkeyispublic,soanattackercandirectlyuseittoencryptarbitraryinformation.
Селецтципхертектаттацк
Скиптонавигатионандјумптосеарцх
Incryptanalysis,СелецтципхертектаттацкreferstoAnattackmethod.Theattackerhasaccesstothedecryptionmachineandcanconstructtheplaintextxcorrespondingtoanyciphertext.
Inthisattackmodel,thecryptanalystcollectsacertainamountofciphertextarbitrarilyinadvance,letstheseciphertextsbedecryptedthroughtheattackedencryptionalgorithm,andobtainsthedecryptedplaintextthroughanunknownkey.