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aa 15 Oeee ox po Cyecye oeco cocoo oe oe aop oye ox aopo. Cy o coaa ooe cxe ec eae oc eoacoc, e ...

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Paouupoa nomoo up Maypepa e Maypep (Ueli Maurer) oca cxey, ocoay a oe XOR opoo eca c eco o op oceoaeoc cyax o [1034, 1029, 1030]. ec aopo capox o ao oceoaeoc. Moo oaa, o ao p o eoace, c epo oc oa opeeec oeo a, eec pacope oa, eaco o ocyo ey ceo ooc. Maypep yepae, o a cxea caoc pao p 100 pax oceoaeocx o 1020 cyax o aa. O cocoo oy pa oo o ec opoa oepxoc y.

17.11 p c acao ecox ooo Ec pooeoc e aa, o e p pa ecoo ooox po oe x aca. oye poeca poco oe XOR xoa aoo eepaopa c op eco.

Peya e Maypepa (c. pae 15.7) oaae, o ec eepaop coy eace , o eoacoc acaa o pae epe e ee eoacoc caoo coo aopa acaa, a copee ceo aoo oe.

oooe p oec e e cocoa, o ooe (c. ay 15). oooe p oo oe aca (c. pae 15.7) c py ooo pa c o pa.

o po ec cooae ooo aopa, ooooo ooo, acoo oo e a cpoo ooooo aopa (oop oe o aop pee OFB). cp aop oe ca, a a poaa oa e oy ocaoo opoo eca, a poaoo o o.

Cyecye coco pae paep ypeeo coco cpoo aopa (oop oe a eoacoc) a acoy ce a. Cea a oa ooceo aco, e co cooa oo aop c o poeypo ycao a. poe oo, cea a e oa ace o ypeeo coco cpoo aopa.

17.12 Bop ooooo pa Ec yee ooox po ae ao-o peya, a o oee c yae peyp o c ce ox cocoo cp. Tpaoo oooe p opac a oy aeaecy eop. y eop oo o cooa oaaeca ooex aec pa, o ee e oo o cooa oca ox cocoo cp pa. o o p o ooo p, ocoa oo a LFSR, ae oe ecooco.

peoa oooe p, cpoepoae ooo o pa : eee peopaoa , oe S-o, .. oe ceo e pac RC4, a ae SEAL. Me oe xoeoc ye peya poaaa peoex o eepaopo, oex LFSR FCSR. a oac aec eca peaeo ye oooc cooa peax papaoax. oye ooooo pa oo cooa o p pee OFB CFB.

B 14- cpae pee peee coooe eoopx aopo.

Ta. 17-3.

Copoc poa ecox ooox po a i486SX/33 M Aop Copoc poa (Ma/c) A5 PIKE RC4 SEAL 17.13 eepa ecox ooo ooo eepaopa ceocyao oceoaeoc Ec yo apoa ecoo aao c p oo ooo oa - apep, yecopa poc peee ec cooae aoo ooa coeo eepaopa ceocyao oceo a eoc. p o oa e ceyx poe : ya ooea aapaypa, ce eepaop o cxpopoa. poe o cooa o eepaop.

Oo pee - apoa eepaop ecoo pa. Ec yo p eacx ooa, apye eepaop p paa opae o ooy y a oo. o eo paoae, o oy cooc p oye oo aco. Hapep, ec oee apoa eepaop oo p paa cpee apoa ooa ax, coee coa oo p ooa. py cocoo ec cooae oo o e oceoaeoc aoo aaa, ooo c epeeo peeo aepo. o eeoaco.

eceo yaa e [1489], aaeoaa NSA, oaaa a 6-. acae xo aeo oo eepaopa poco m-o co pecp. o aoy aooy ycy cae pecp a o pao. ae aoo xooo ooa oe AND pecpa c py m-o eo po, paccapae a ya eaop paoo xooo ooa, ae oee c oo XOR ce , oya xoo oo ooa. Ec peyec oy apaeo e coo xox ooo, aoo xooo ooa yo cooa oe eop oec acc XOR/AND.

eepaop...

m-o xo Beop 1 Beop 2 Beop n oooe oooe oooe AND AND AND oooe oooe oooe XOR XOR XOR oo 1 oo 2 oo n Pc. 17-11. eepaop ecox o.

Cyecye p ee, oope yo ocea. Ec o x ooo ec eo o ae pyx ooo, o ccea oe oaa. Ho ec ocaoo aypa, oca coco ec poc eoac cocoo pee poe.

17.14 eepaop peax cyax oceoaeoce oa popaec eoace ceocyae oceoaeoc eocaoo xopo. B p opa a oy oaoc eceo cyae ca. epoe, o pxo ooy - o eep a e. pepaco oo eeppoa cyae popaece , coy eepaop ce o cyax oceoaeoce, o ec pa oye o oo eepaopa a , o coe co a e e oa ay poccey, eaco o aeoc ax aopo. oceoa eoc, aaey eepaopo cyax oceoaeoce, ocpoec eooo. Ho, ae ca, e coe ocpoec oceoaeoc o, aaey eepaopa.

pyo ococo poeo ec opoc o o, a eo eceo cyae . e copac ac o cop. ec paccapa ay o, oope eooo o c poec, y oopx cacece coca a y cyax o.

oo eepaopa eceo cyax oceoaeoce a opoco ec eo p o epa. Ha y ey cyecye oeco epayp. Tec a cyaoc oo a [863, 99]. Maypep oaa, o ce ec oo oy o ca oceoaeoc [1031, 1032]. Ec cyaa oceoaeoc caec, o oa e ec o acoey cyao.

B o cyae, ce, o ee o oac, o oo oocc epo a. a oe o ec eepa oceoaeoc o, oopy e coe yaa a po. o opao o ee pya aaa, e aec. e oy oaa, o o ocax eoo eeppye cyae . Peyao x pao c oceoaeoc o, oope eooo eo ocpoec.

opooc oo a [1375, 1376, 511].

Tau RAND a ao, 1955 oy, oa oep ce ee oy, Rand Corporation aa y, co epay o cyax p [1289]. x eo ocac a:

Cyae p o oye p oo paoa ocoo a, ceeppoao e poo pyeo. Bpae, co yco, a x co cyao acoo cpee ooo 100000 yco ceyy, opac pa ceyy yco ocoo aco. e opaa yca poyca yc e pe 5-pap ap ce. o cy aa ac oeco pye c 32-o, oopoe cpee eao ooo 3000 oopoo a opy aao oo co ceyy. cooac oo-ec peopaoae, o op peopaoa 20 32 ce (ocaec eaa opacac ) oca oo oce py ya x ce. ocee p oaa oocep IBM, opay oe oo ay pox apoe cyax p.

B e paccapac peya pax poepo ax a cyaoc. B e ae peaa c coco, a cooa y y opa cyaoo ca :

Cpo a p yepyc o 00000 o 19999. p cooa a yo caaa pa cyay capoy o. Oo poeypo oo ec ceyee: opoe y y a pooo cpae a p , ap aa, epe papoe co. o co oce ae epo p ocao o ee ee a 2 opeee capoy cpoy. Ocao o ee yx p cpaa o epoaao paoo papoo ca a 50 aae capo coe capoo cpoe. o ac o op ce pe a oo cpae ecec eoo cpee pa co oe epy cpa, aoe cooaoe opeee capoo o papoe co oo oeeo e oo oe cooac o e.

a coepae o a "Taa cyax p". p poc pap pya - "10097 32533 76520 13586...'' - o 50 cpoe o ec cpo a cpae. Taa aaa 400 cpa , a cee ocoeo aec py a cpae 283, ee a "69696", a ocaoo cy o. B y ae xoa aa 100000 opax ooe.

epec e RAND c e o cyax p, a o, o o coa o o epo peo. Bo ox popaecx aopax coyc pooe oca - a a aee "aece ca". Bop aecx ce a RAND apapoa, o o e pa ceao o a-o yec pa. Ta, apep, o ceao Khafre.

cnooaue cyaoo ya y cocoo oy ooe oeco cyax o ec eee x ececeo cyaoc peaoo pa. aco ao eo peye ceao aapayp, o o p oo p e oepax.

Hae coe, oopoe cyaec peypo, o cyao: aocep y, peooea ao-o opo, peeo, aa, yac xo. epe epa ey o oo coe coe, cey a . ae. epe peeo epa ey op pe co. Coa a e. Ec ep peeo epa oe opoo, xo o ye 1. Ec opo epa oe epoo, o xoo co ye 0. Ceae o coa ceyeo co .

poce cpey apc epee opoo H-opco ooo pe eco aee. Cpae o poy a, oopy oa, c opoo a po a e. Ec oe a, oopy oa, xo pae 0, a ec ee - 1.

oe oepy ce eepa, ocae oeco yco a cpoa epa pee oe a . epe pe ey oceoae a ticks. (Ta a pao a co pacaaec, cpeee pe ey oceoae a epepo yeaec.

o oo ea, ao pa co c ocaoo epoo oypacaa - ao a y o. Ec ecooec o coe opoe, oee ec cooecye cacece opa.) . . (G. B. Agnew) peo eepaop peao cyax o, oop oo eppoa CC [21]. o oecaop ea-oop-oypoo (metal insulator semiconduction capacitor, MISC).

a ax oecaopa oeac po py c pyo, a cya ec ye paoc ap o x oecaopo. pyo eepaop cyax ce eeppye oo cyax o, coy e caoc aco cooo oeeoc ocopa [535]. oepeca pocxea o AT&T eep pye cyae ca, opac eo a o ee [67]. M. (M. Gude) ocpo eepaop cyax ce, copa cyae ecx e, apep, paoaoo pacaa [668, 669].

Ma Pxep (Manfield Richter) papaoa eepaop cyax ce a ae eepaypoo ya oy pooooo oa [1309].

peooeo cya peee epa ey oceoae 2e4 ye cea pac aaeoc aoa py. coye. A ye ae oypoooy py, oopa oaae pocxe eepaopo cyax ce, x ocaoo oo.

Cyecye ae eepaop cyax ce, coy c oepa [439]. O epe pe, yoe e oa ca, coye ee oo pee aece coa cyax ce.

ae pyc, o ya cpyypy, ay aoae, ae eopa ce peec cpoe peopaoae ype. o ycpae ceee oppe. Haoe, aece cyax o coyc cepae y aco aaoe (0, ), opaoae a e epa.

oa ac ee copoc pae ca aa ypyeoc oyxa, oopa ec c oo cyaoc ccee. Xo ao yec ceyee. Ec aee a xo co oo o, o coyee aece eepaopa cyax ce cpoe peopaoae ype pcyee o y opeeey pecayeoc. ye coa coa a o o e co o, o a e poc poa cpyypy, coo oopo ec apo ca. Peaa ao cce ooa oya ooo 100 o yy [439].

cnooaue maepa onmepa Ec a ye o cya ( ae ecoo), ocoyec a aa o oo pecpa aepa. B ccee UNIX o oe e co cya -a pao ooo cxpoa, o a eoopx epcoax oepax o paoae.

He co ea a opao co oo o. Boee oo pa oo o e poeyp oceoaeo oe eo cec , eeppoae cocoo. Hapep, ec oee a o poeyp eepa a aae eoe co o aepa, a xoe aeo eepaopa ye e c oea oceoaeoc oaox o. Ec oee ao poeyp eepa a aae eeoe co o aepa, a xoe aeo eepaopa ye ecoea oceoaeoc epey xc o. ae ec acoc e a oea, oyac o oo ye ae o cyaoo.

O eepaop cyax ce paoae cey opao [918]:

Ha eepaop eceo cyax ce... paoae, ycaaa y ae cpo peepy p e cp cea poeccopa o ex op, oa e pooe pepae. aee oec XOR coepoo pecpa co epoo aa xooo yepa (ae pecpa yceac o 8 o ). oce oo, a ye aoe a a xooo yepa, yep oepaec aee opaoe ec co aoo coa pao a a a.

o po ey epeee aoee ax ( cyax) ax aax o cape aae o . ae ec poecc oopec p paa. Haoe oce pepa a cax cyax a pecpa cea o a a co yepa. To ec pocxo 4n pepa, e n - co yx cyax o.

o eo oe ycee cyaoc ccex pepa aoaoc aepa. p ec poa a peax UNIX-aax peya oe eox.

epeue cpmoo cocmou auamyp poecc eaa cyae, ecyae. O ocaoo ecyae, o eo oo o cooa ea eaaeo eoea, o o ocaoo cyae, o eo oo o cooa eepa cyax o. epe pe ey oceoae aa a, ae ocoy ec a aa a x epe. oaac ocaoo cya. o eo e paoae a UNIX-epaax, a a aa a pee, e o yy epea ae popae, poxo epe p pye exa, o o ye paoa a oce epcoax o e po.

B eae o o aoy aa a eeppoa oo o . cooae oeo oeca o oe cec peya acoc o ao ac. Oao o eo ee p opae. Xo epyo oca a aaypy eoea, eaaeo co copoc 100 co yy ooo oo, ec ec pe eepa a, yo poc acy eaa ec co, o cooa peya pao eepaopa aece oopaooo ooa.

Ceeu u oppeuu ao poeo oox cce c ooe aooepoc eeppyeo oceoae oc. coyee ece poecc oy cya, o ey ec poecco o epo axoc pae epee cpye. cpye oy eo pec oe poe.

Cocoo ycpa ceee, ooee, ec XOR ecox o py c pyo. Ec cy a cee 0 a ey e, o epooc 0 oo aca a:

P(0) = 0.5 e XOR yx ax o ae:

P(0) = (0.5 e)2 (0.5 - e)2 = 0.5 2e Te e ce XOR 4 o a:

P(0) = 0.5 8e XOR m o coeao cxoc pao epooc 0 1. Ec eco acaoe ceee, oopoe oyco ae poe, oee c, coo o a yo oe c o o XOR, o ye ceee o oo ae.

Ee ye paccapa oapo. Ec 2 a oao opoce x e a ceyy apy. Ec 2 a pa, coye ep aece xoa eepaopa. o ooc ycpae ceee. pye eo yee cee coy pacpeeee epexoo cae cpoe p e opaoae ype [511].

oeao poeo oox eoo ec o, o p a oppe ey coce a eo yea ceee. O cocoo cpa o ec cooae ecox cyax coo. Boe epe cyax coa oe XOR o py c pyo oe a cyax coa e a x oapo.

Hapep, oe paoa co pcoee ce eepa aey oepy. Bo e apy yx oo acae aece co aoe peee opeeeoo ae.

epe aocep y. ee aoo coa cya oe x XOR py c py o, oya cya . Boooc ecoe.

Oo o, o eepaop cyax ce cee e oaeo oaae eo ecoeoc. o oo o aae, o o eee eoace. Hapep, paccop poey Ac, eeppye 168-o pooo DES. A ce, o y ee ec, - o eepaop cyax o co ceee 0 : c epooc 55 po eo o ae y c epooc 45 poeo - e. o oaae, o po a a c o ca oo 0.99277 ( eaoo eepaopa oa paa 1). Mop, ac pacp , oe o poa oeoe cpe pyo co, poep caaa aoee epoe (000... 0) ac aeee epooy y (111... 1). -a cee Mop oe oa, o ey yacc oapy a 2109 oo. p ocyc cee Mop opeyec 2 oo. oye eee eoace, o o paec eoyo.

eea cyaocm B oe cyae y coco eeppoa cyae ca - a ooe oeco ayxc c y a co e cyaoc x. a cyaoc oe xpac aoee eac p eoxooc..Ooapaee x-y pepaco oxo oo. O cp, ooy oee poyca epe x, e co aoc o pooeoc eceo cya o c aoo ae. opoye xpoa o ce, o a aec xo y-y cya. H a pep:

o aoo aa a a oa Hoep ceopa, pe aepa oca ao coo oepa eceoe ooee Hoep eye cpo paep oopa Coepae eceo ooo a pa opae Coepae FAT-a, a pa, ..

Bpeea ocya/ee /dev/tty apya poeccopa Bpeea ocye ceex aeo Bxo pooa /dev/audio e pcoeeoo pooa Ec aa ccea coye pae pca-ocop coeo poeccopa aco, oa ec ca pe oo e. B eoopx (o e cex) cceax o pee cya oe a a ey y ocopa.

Ta a cyaoc x cox opeeec cxpoae ocopo, coye ac c a oo e ao pee. B caapo PC coyec pocxea aepa Intel 8254 ( a ea), paoaa a aoo acoe 1.1931818 M, ooy eocpeceoe cae pecpa cea ac papeee 838 aocey. o ea cee peyao, e coye aece coa co pepae aepa. Bo a o poecc a e C c MD5 (c. pae 18.5) aece x-y:

oce ocaox oo churnrand() aoe ocaoo cyaoc Randpool, oo eeppo a oo cyae . MD5 coa caoc oeo, o pa aece eepaopa ceocya oo aooo ooa, paoaeo pee cea.

o o pa x-y ee eoe aee. Bo epx oa oeceae poco coco eeppoa poooe oeco ceocyax ax, e a c pa churnrand(). Ha ee, oa aac aoee oxo oy, ccea oceeo epexo o coepeo cyaoc pa eco. B o cyae caoc meopemuecu oo cooa peya oa genrand() opeee peyeo oceyeo peyaa. Ho oo opeyec eppoa MD5, o ceo eooo.

o ao, a a poeype eeco, o eaec oo co cya a, oope oa op a ae. O o poeyp oe eeppoa cyaoe co poooa, oopoe ocaec o e, ooo oe a po apoc oa. A cey o oe eeppoa cepe coce pyoo ceaca c, cy oopoo xoe poy o. Oea aoc oo, o o e co oy cepe , coy ooy cxey ec.

Ho ocaec oa poea. pee, e ep pa ye aa genrand() acce Randpool[] oo aoeo ocaoo cyax ax. Ec ccea aoe-o pe paoaa c oa ooae e, o-o eaa a aaype, o poe e. Ho a ace eaco cce, oopa epep y aec aoaec, e opaa a a ae ae aayp ?

Ho ec oa pyoc. B aece acoo pee oo opeoa, o oce cao epo a py oepaop aoe-o pe opaoa a aaype coa a ce capo a epe pyo oepaoo cce, o xoe epeapyo cooac cyae ae, epeae Randseed[].

Ho e coxpae eocpeceo ca Randseed[]. Bo, oopoy yacc aoy o a, coe opee ce peya genrand() oce oceeo opae churnrand() pee, e o a ye coa.

Peee o poe ec xpoae acca Randseed[] epe eo coxpaee, oe ae oo genrandO. p epeapye cce caee ae capooo aa, epeaee x churnrand(), a ae eeeo cpaee x. coae o e ycpae ypo oo, o oye oye a ey epeapya coye eo pecaa yyx ae y genrand(). e y oo pee o poe poe, a ooa aoe ocaooo oeca cyax co, cyxc oce epeapy, pee, e oo genrand() aa peya.

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