crypto-hashes - 3 piIGF Bc H D ic HPF D HP Pi Bc D joPc...

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Unformatted text preview: 3 piIGF Bc H D ic HPF D HP Pi Bc D joPc jg9ijQc o @Bc i h g P h H H h H g h c H H D e c h g 6 eP F B A pgc irbjP b`c pj`jP jGPS QF c $`$iD 3 26 8 B c h c g h i DP i cP D P D h h cP 6B 8 P g c H h H t x$tjD p6jQtQii0ipF iP 3 0bE &bc 3 iD i Uh 3 H3 W i DP 8 @ ic B6 c "6jB 3 u c P @ 6 g P @ P @ B i h HP BcPPc P h PB 6 c fcA c00p6t8B 3 c 8 pbjtEf7cEoPeD Q8 W P Qic 3 B6 F jc gc ejQcjP IG pbjP t0 g 6 c h BD P i c H F iD i FD i h H B c P h g Ph D B c BCbiIGFjݻ6 tP00 @fU 3 D8 jGPStc ڽh UW gc @ c H D e c @ g P i h P D B i 6D D 9pEjc ιeQ6 3 R W P 4ct28 g6 3 E { Cp"ph W 6 P P h i h g c ph jH di B c H h @ h ec U & r& r s ̨ W i DP DPic HP Q6jrh 3 jQj2Uh iD Bc D i c ʻ6 3 c E g rj`cjfcijyU`0pH c pc jP P Ph HP DP P Bc HP6 6 P 6 h B h Bc H i Cph 9c 3 eD A c 3 6 fa ʿ c 0ʿ g liX a @ i nm c P d X a W B D Ao@UhD gjc 3 D trh 3 jQjph ph 3 96 9̿p9rbjP cP DPic HP i Wc h Ph H c 3 C6 Bc ticby` tP G@yeDD 2d kc 3 AbyʱI 8 B 6P h c 6 c g f 6P 3 h c h H P6 i c 6 P H @P h 6 i c D c H h c H DBc ic H i rhbjP Bp8 i ph "Aoc 3 0B j bH P @ G P ph 3 c 3 D d B c 3 QjP oPSe trh 3 j i6 i c H H D cPh icP i g f P c 6 3 2d ifc B 3 iQ6 g 6 3 y6 j b$jP jGPS`cDc B 96 R g h H hH cH H D e 8 W cF h 92icpbH 3 c 3 i h 96 c 3 eD W i6 ic h g d 2d d f d e W hcP c Ug0iD ʿ c @h g ihc 3 6i iceUbH 3 cjP 2eijB 3 c 6 t Y F D H H i cF h H F DP 8 @ i i c h jfc ˻6jrh 3 D9cj2ph&iQ8c BǴF2cphH 3 ipbjYjrdV 6 HP g i DP Pi HP c 6 c i h F D ih HP Bc HPh pY{pݱp G r o W i D P gB 6 DBB 6jrh EiD cEEph 3 oPD h I c h 6 g H DB 6 ` P AbH tP CoPEGFph w jP 2ei{zeDUhjoPiD A GPĻ cH F D D D @ D B6 cP g Hh h i I 6P c c @ 8 Q6 3 jH eDU9h Cph yt'ph g Žh g Q6joPUh i D D c Qtgf b oPph xrc h AGAggrbj"pgc g g6 I Hh H D i I c Fh g ic D FPh HP ih DH W"7j'ri2t6 jP h t irjP oP9pb25 ic c HP Ph P 8P Hh H c H c D Ph H @ DPih c gU cjP bH jP 2eij2b8 6 3 Se ̿p9 trehc EtQiD h H Hh c H F DP g ic H c h cP D gBcP i h c g H B6 Uh ʿd jGPDEQFph w vpehpU׻ftAo@trbCλi r B 8 6 8 h B c c c P h i P B 6 W IuU6 PoEIstPQiHP 3 H 3 tr껢jGPc Uh 3 @ DB Fc D c c B 6 cPhBc ic F Bc H D i f g Se$tUHjP GCi6 hbjP 6ʿ h g I h d e 6 i 6 H c 6 @ P H c c @ f eph tP Sgʹ D c 3 i9c 3 stPyi 'GPD A 6 i e6i D 6 c 6 c @ I c 6 @ DB Fc c h 5 B 275 oPAsP9i F jc hBu H dʻ6 h 2ei 6 H h @ h ec i F D p '" q p & } Vpe ~d| IV K F F Hashing for MICs F M H(K|M) F P ! } ec ~d| IV K F F Attack on MICs F M H(K|M) F P H(K|M|P|A) A P' F 7 { WP c c H c h 6 @PB h 8 Bc HP i 6 c H fc B 3 jP AH P p7jy6 o@jP crhc g jrbjP 2eijrh 3 jQjp'`h 5 F c HP Ph H F DP DPic HPh c e 5 cHjP jP f0B 3 j g pY8 jy6 ic H f Pc c c HP e6 i @PB h Bc HP 5 j P t2b8 6 3 jP U GpbH c H P h I cP g c H 6 h @ Pic h AQ`de h h c Bc ci i6 ʻ6 o@& o@t r R i6 c W W hcP D pgt0i f h t r W I c W e 6 h B h @ h 6 W @ h e hB c c g g6eQu` c pdde e dYpAfU6 @i 9ph eiD Aoͻ o@egD Uw jGPSe c96 7yH c 6 Dhc ih R H D g B8 h P6i D D ` R f s d ) A f R f s d A f 2 % R s ή f ) A R s f A R f s f d 1 7 h A joSe A c 3 bc B ph H PD h 8 i Qc c B 3 jP W @ P i g c icH A B Ph HP c DBc ih cP g ic H r`oEA p7 t2b8 6 3 jP W c h F jc g 6 H tPDjPCt Cp A A 8 Q6 3 tW ic ih cP g C @ B c 2jP jGS`ebc B g i c H H P D e c D 8 R W l9c pbH 2eGAF tE6c B Ct tW g h i B c F iD D 6P Pc 5 ic 6P c Bc H cP DPic HP 6P Pi tGt trh 3 jQj2ph tQUh e H 8 ic Lamport Hash Authentication - Method for authentication even if someone reads server database - A chooses password_A, n, computes H(password_A), H(H(password_A))... - Server holds A A n get password_A X=H n-1 (password_A) check that H(X) = Y decrement n, set Y=X n (A, n, H (password_A)=Y) S } } } } Eyee̱d| 0t 5 ) &9% $eRs rfRqg &py i93 $Xhg fleR D c % % ! ) ) F % d b a p # % `Y X%pyWy0!# DT ! V U % ) % @ S R% 0 Q RPI ) TH "GFE REDRB % % C X R Ay! @ 869 p 864 2 7 5 3 7 5 3 1 0)py('&% $ #y" # T # f4 ! ! wv % E ! p u $R A&kT$ y! n l % ! ! @ % ! F ! % % D R# R# P'y AeR i l % ! ) n pR&% t A(F R s0 & triq"pgiuDT ! 3 ) % % % 3o n( @ S H #Pmi rRg T $T% ly! ! 3 l % % ) T% gȵ% e3 # E ! p&% k $eRk#@ (jRB % @ F 1 ) #@ (F $p9 @ D p i(h g e 44 Y % @ ! F y x y w fegd8r S 6SE" pSw v u w y x y yx w} } |{ }E}eBPd| z y x } M: C Hashing Using Encryption K1 E K2 E K3 E H(M) Kn E @ "#PRRP% 1 e ( 3 # % R 3 F % ! ! )! t # % ` X $eE @ (F 1 $ y(4kq"pgDR Y % ! 3 % % ) % ! ) ) $&$ 9R TE (wX% A ) #@ fD c #@ "F $TE y( q"E $R DT ! % n H l B d % g"E $ &% &% T% $ F ) t#@ R tDRB ) )C "F $AlF T' WSR R )! % % % F % % g(ipTr Rg lFR ) 1 d &% 1 p @ "HRP49( % F % 3 % X ) T% $ d%g( &% 1 pȨ n % ei'9l ! &9rHg4 F ! % F ! % F ! 4 @ % R fRgȵ% 3 & R q% &pTR 3 y! y$ % ) % ) % % ! y eD"pi 6(~ ~ w y x y w q S "jq"eie (~ } | } VET d| } M: Generic Hash Function Operation IV int F int F int F ... int H(M) int F P % F r 1 A% $ g( T ! % 1 % g R j y% eE $ &X % n " el g $ $eE y"y! T% F c @ ! ! n 0TX%tymT% $ R$TiiX% R! 3 1 ! l ! )! % F B ! ! @ gq T% F $ee !( p&9 1g E ) $ ) t#@ R g $ HR R % ) 1 pyeX% T% $Rpl g ) R &f!$ $Tg( &g@ R T% $ % % ) ) F g c n ( ! F T% F r Il T% F k D e0 % 3 4 "GX% ) T% $ g( &% 1 p T% F ! &9%rHgT % ! F! %r 1 WX%$RB F B R# % g( $T%ip Ei T% j4 % ) ! F e6(~ MD2 1. Pad original message p bytes, all = p p <= 16 bytes multiple of 16 bytes (128 bits) 2. Append checksum 3. Compute intermediate values for each 16-byte chunk 16-byte chunk intermediate phantom byte(-1) (init to 0) byte 0 byte n-1 byte n byte 47 message chunk + pass# pi-substitution (0-17) new intermediate discarded 4. Last intermediate value is MD2 hash value (digest) } j t d| % F r 1 A% $ g( T$ ! % T ! 3 % % eE i 12 E ) S k ei rRg ) &X ! % 1 % ! g R $ TE T &X % % TXty!mT% $ R$TiiX R! 3 1 ! ) ! % % F B ! ! #g T% $ $TE y(j @ F ! p T% $R $h &% 1 p 9% c 4R F n TX%F $Rl B % F c f4 (wX ) &% &EȨ T%XF c T% $R j c 3 % % % q"E &% 1 p 'X%F ! !&9%r! n rf ) ET F % l % F B r 1 WX%$RB #ȵ% %q" R 9D44 ) ! % F B T 6(~ x % F r 1 A% $ g( T$ ! % TE ! % % % ! !i 1g e ) S 3 ei R# ipy$ 9 &X% 1 % ! g R $ TE c &X % TXty!mT% $ R$TiiX R! 3 1 ! % ) ! % % F B ! ! #g T% $ $TE y(j @ F ! p T% $R $h &% 1 p 9% c 4R F n TX%F $Rl B % F c f34 Ȩ(wX ) &% &EȨ T%XF c T% $R j c % % % q"E &% 1 p 'X%F ! !&9%r! n rf ) ET F % l % F B r 1 WX%$RB #ȵ% %q" R 9D44 ) ! % F B T 6(~ MD5 1. Pad 0 message m A = 0x01234567 B = 0x89abcdef C = 0xfedcba98 D = 0x76543210 2. Initialize 128 h 0 = ABCD A0 128 B0 C0 D0 H fF k 10000...000 Lx512 bits M0 512 H A1 B1 C1 D1 T0 128 h 1 A2 B2 fGC 2 D2 T1 f H h H 2 A3 B3 H C3 D3 T2 f A4 B4 I C4 D4 T3 A0 B0 C0 D0 +%2 32 +%2 32 +%2 32 +%2 32 128 hi 3. Mangle H 128 h h L M1 M2 ... M L-1 4. Result k%2 64 h i-1 x pST v d| } MD5 (con't.) F(X,Y,Z) = (X & Y) | (!X & Z) G(X,Y,Z) = (X & Z) | (Y & !Z) H(X,Y,Z) = (X + Y + Z) I(X,Y,Z) = Y + (X | !Z) X-select Z-select parity ??? A0 128 B0 C0 D0 H f A1 B1 F C1 D1 T0 f A2 B2 G C2 D2 T1 A3 B3 f H C3 D3 T2 A4 B4 A0 +%2 32 +%2 32 +%2 32 +%2 32 128 hi f I C4 B0 C D4 0 D0 T3 h i-1 } w x } tj } | t v % F r 1 A% B g( T ! % # % e3 1 1 ) $T% " 1 4 ) 1 % ! g R $ TE &X % TXty!mT% $ R!$TiiXD$ R! 3 1 ! % ) % % F ! ! #g T% $ $TE y(jR @ F ! 1 H d gc D c d % q"E &% 1 p 'X%F ! !&9%r! n rf ) ET F % l % F r 1 WX%DRB #ȵ% %q" R! 9D44 ) % F B T e6(~ } $ i y ! ! 3se3eR 0 lp9l0 F S 8s ) % $TR fT%# ! @ (F( p y!P% 1 ͨ %X 1 k DRB C d o D4 d t 6(~ ...
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This note was uploaded on 01/17/2012 for the course CIS 6930 taught by Professor Staff during the Fall '08 term at University of Florida.

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