Secure Audit Logging with Tamper-Resistant Hardware

C.N. Chong, Z. Peng, P.H. Hartel

Description

Secure Audit Logging with Tamper-Resistant HardwareCheun N Chong Zhonghong Peng Pieter H HartelDept. of Computer ScienceUniversity of TwenteThe Netherlandsfchong,zhong,[e-mail] the rights on the content, such as cryptography,digital ngerprinting, watermarking etc. In thisSecure perimeter schemes (e.g. DRM) and tracing paper, we assume that users can be identi ed, andtraitor schemes (e.g. watermarking, audit logging) we concern ourselves with the issue of gatheringstrive to mitigate the problems of content escap- information on the user’s behaviour.ing the control of the rights holder. Secure audit Secure audit logging records the actions of a userlogging records the user’s actions on content and on an item of content and does so in a manner thatenables detection of some forms of tampering with allows some forms of tampering with the log tothe logs. We implement Schneier and Kelsey’s se- be detected. We implement Schneier and Kelseycure audit logging protocol [1], strengthening the secure audit logging protocol [1], using tamper-protocol by using tamper-resistant hardware (an resistant hardware (TRH). For brevity in the se-iButton) in two ways: Firstly our implementation quel, we refer to Schneier and Kelsey [1] as \SK".of the protocol works o ine as well as online. Sec-An audit log is an important tool to detect andondly, we use unforgeable time stamps to increaseto comprehend damages of a computer or networkthe possibilities of ...

Informations

• Publié par: Astlio
• Nombre de lectures: 40
• Langue: English

Extrait

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]8lkkfe ]e k“X TlW]k cf[[]e[ gifVXjj) L“XiX ]j fecp dcP TlW]k cf[ ffcX ViXTkXW Yifd k“X gif( VXjj) /) CY k“X ]8lkkfe ]j iXdfmXW Yifd k“X ]8lkkfe iXTWXi “TcYnTp k“ifl[“ Te ]ejkilVk]fe k“Xe k“X cf[ ffcX ]j VcfjXW TUefidTccp n]k“ T iXT( jfe jkTkXW ]e k“X cf[ ffljXX =][liX 1)) FcbU C2 (KNR (.) NbeFeibn =fi UXkkXi leWXijkTeW]e[ fY k“X iXdT]eWXi fY k“]j gTgXi’ nX ljX k“X Yfccfn]e[ efkTk]fej Yifd KE) • I, x iXgiXjXekj T le]hlX ]WXek]ffXi jki]e[ Yfi Te Xek]kp h ) • I FA P K x ffl F ) ]j k“X glUc]V(bXp XeVipgk]fe fY F lj]e[ k“X glUc]V bXp’ I F x fY h ) L“X VfiiXjgfeW]e[ gi]mTkX(bXp WXVipgk]fe fY F ]j I F, SK x ffl F )’ n“XiX MF x ]j h ffij gi]mTkX bXp ffljXViXkbXp))OXljXk“XJK7Tc[fi]k“dUX( VTljX ]k ]j TmT]cTUcX ]e k“X ]8lkkfe mXij]fe iX( cXTjX -: -) • MIDN SK x ffl Z ) ]j k“X W][]kTc j][eTkliX fY Z ’ le( WXi h ffij gi]mTkX bXp) OX ljX JK7 n]k“ T bXp j]qX fY -.4 U]kj) • A K ffl P ) ]j k“X jpddXki]V bXp XeVipgk]fe fY P leWXi bXp F ) , K ]j k“X VfiiXjgfeW]e[ jpd( dXki]V bXp WXVipgk]fe’ n“]V“ nX ljX ]e TWW]( k]fe kf KE efkTk]fej) OX “TmX iXeTdXW F 0 ]e k“X KE kf LF 0 kf W]jk]e[l]j“ ]k Yifd k“X cf[ Xekip XeVipgk]fe bXp ]e jXVk]fe 0)-)/) F VTe UX LF n ’ fflT iTeWfd jXjj]fe bXp) fi F iB ) OX ljX j]e[cX :;K) • H A. K 0 ffl P ) ]j k“X dXjjT[X Tlk“Xek]VTk]fe VfWX’ leWXi k“X jpddXki]V bXp F 0 ’ fY P ) OX ljX T feX(nTp “Tj“ G79 Tc[fi]k“d’ eTdXcp BG79) • YRgY ffl P ) ]j Te feX(nTp Vfcc]j]fe(iXj]jkTek “Tj“ YleVk]fe Yfi n“]V“ nX ljX k“X KB7- Tc( [fi]k“d) • P; Q iXgiXjXekj k“X VfeVTkXeTk]fe fY P n]k“ Q )

2

.4(..3bR1necyCbndecuLeibnAuTNd OX efn jlddTi]qX k“X KE cf[ Xekip VfejkilV( k]fe ilcXj UXcfn’ ]eW]VTk]e[ k“X ifcX fY k“X ]8lkkfe n“XiX Tggifgi]TkX) -) , j ]j k“X iXTc cf[ WTkT ]e j k“ cf[ Xekip fY I, log ) =fi T :JG Tggc]VTk]fe’ k“X WTkT j“flcW XeVTgjlcTkX ]eYfidTk]fe Yifd k“X W][]( kTc c]VXejX’ TVk]fej k“X 9c]Xek XoXiV]jXW fe k“X W][]kTc VfekXek’ UX“Tm]flij fY k“X VfekXek iXe( WXiXi TeW fk“Xi iXcXmTek ]eYfidTk]fe k“Tk fV( Vlij Tk k“X 9c]Xek) .) N j ]j k“X cf[ Xekip kpgX fY k“X j k“ cf[ Xekip) /) A j ]j k“X Tlk“Xek]VTk]fe bXp Yfi k“X j k“ Xekip ]e k“X cf[) L“]j ]j k“X VfiX jXVli]kp fY KE) 0) F j = YRgY ffl 00 AcTeiptZdcFei 00 ; N j ; A j ) VTc( VlcTkXj k“X j k“ cf[ Xekip jpddXki]V XeVipg( k]fe bXp) 1) Q j = YRgY ffl Q j − + ; A K j ffl , j ) ; N j ) ]j k“X V“T]eXW “Tj“) ;TV“ cf[ Xekip VfekT]ej Te XcXdXek ]e T “Tj“ V“T]e kf Tlk“Xek]VTkX k“X mTclXj fY giX( m]fljcf[Xeki]XjR./]) 2) Z j = H A. A j ffl Q j ) ]j k“X G79 VfWX fY Q j [Xe( XiTkXW leWXi j k“ Tlk“Xek]VTk]fe bXp’ A j ) 3) G j = N j ; A K j ffl , j ) ; Q j ; Z j ’ ]j k“X j k“ cf[ Xe( kip Vfej]jk]e[ fY k“X VfeVTkXeTk]fe fY k“X Yfli mTclXj c]jkXW) 4) A j ++ = YRgY ffl 00 IcTeebectE RgY 00 ; A j ) [XeXi( TkXj T jlUjXhlXek Tlk“Xek]VTk]fe bXp Yifd k“X giXm]flj feX) .(4. ESN PcbLNdd KE- ]j W]m]WXW ]ekf knf gTikj6 ffl-) ViXTkX cf[ TeW ffl.) VcfjX cf[) OX gTp dfjk TkkXek]fe kf k“X TlW]k cf[ ViXTk]fe gifVXjj UXVTljX nX TiX ]ekXiXjkXW kf befn k“X ]efllXeVX fY k“X ]8lkkfe fe k“X 9c]Xekffij gXiYfidTeVX) CcNFeN3bR =][liXj / TeW 0 j“fn k“X gifVXjj fY ViXTk]e[ Te TlW]k cf[) Ce KE’ k“X MekiljkXW dTV“]eX fflk“X 9c]Xek) jXeWj ]kj glUc]V bXp VXik]ff( VTkX kf k“X LiljkXW dTV“]eX fflk“X KXimXi) Yfi Vc]Xek Tlk“Xek]VTk]fe) L“X ]8lkkfe’ n“]V“ nX ljX Tj T

4

LiljkXW dTV“]eX Tj XogcT]eXW ]e jXVk]fe -’ Tlk“Xe( k]VTkXj k“X 9c]Xek lj]e[ T jkTeWTiW Tlk“Xek]VTk]fe dXk“fW W]jVljjXW Ui]Xflp ]e jXVk]fe 0).) L“X jkXgj TeW dXjjT[Xj fY =][liX / TeW =][liX 0 VTe UX XogcT]eXW Tj Yfccfnj6 -) Lf jkTik TlW]k cf[[]e[’ k“X 9c]Xek kTbXj k“X ]e]k]Tk]mXUpTVk]mTk]e[P-)7YkXiP-’k“X 9c]Xek “Tj k“X ]e]k]Tc Tlk“Xek]VTk]fe bXp’ A 0 TeW k“X VliiXek XeVipgkXW k]dXjkTdg’ A K iB ffl W 0 )) KE cXTmXj ]k kf k“X 9c]Xek kf WXV]WX 0 TeW W ) OX cXTmX k“XjX knf ]kXdj [ XW A Xe XiTk fe k“X ]8lkkfe’ Tj XogcT]eXW ]e jXVk]fe 0)/) ’ LF ; .) L“X 9c]Xek Yfidj T iTeWfd jXjj]fe bXp 0 k“X k]dXflk gXi]fW k“Tk k“X 9c]Xek n]cc nT]k Yfi k“X iXjgfejX Yifd k“X ]8lkkfe’ W 0 ”; T le]hlX ]WXek]ffXi Yfi k“]j cf[ ffcX’ I, log ; TeW T efeVX befne Tj jkXg ]WXek]ffXi’ p ) L“X 9c]Xek VfeVTkXeTkXj p ’ A K iB ffl W 0 )’ TeW A 0 kf Yfid k“X dXjjT[X P 0 ) /) L“X 9c]Xek XeVipgkj LF 0 n]k“ k“X ]8lkkfeffij glUc]V bXp’ I F iB TeW XeVipgkj k“ j][ 0 X eXW P n]k“ LF 0 ) L“X 9c]Xek Yfidj T dXjjT[X’ H 0 Up VfeVTkXeTk]e[ p ’ I, C ’ k“X XeVipgkXW LF ’ 0 TeW k“X XeVipgkXW j][eXW P 0 ) 0) L“X 9c]Xek [XeXiTkXj TeW jkfiXj k“X “Tj“ fY P 0 Yfi mTc]WTk]fe ]e k“X jlUjXhlXek jkXgj) 1) L“X 9c]Xek jXeWj k“X dXjjT[X’ H 0 kf k“X ]8lk( kfe) 2) L“X ]8lkkfe iXki]XmXj k“X iTeWfd jXjj]fe bXp’ LF 0 Up Wf]e[ gi]mTkX bXp WXVipgk]fe) L“X ]8lkkfe VTe k“Xe WXVipgk TeW iXki]XmX P 0 Up lj]e[ LF Tj T WXVipgk]fe bXp) L“X ]8lk( 0 kfe mTc]WTkXj P 0 Up mXi]Yp]e[ k“X j][eTkliX) =]eTccp’ T eXn iTeWfd jXjj]fe bXp’ LF + ]j [XeXiTkXW) 3) L“X ]8lkkfe Yfidj dXjjT[X P + ’ Up VfeVTkX( eTk]e[ k“X jkXg ]WXek]ffXi p ’ I, log ’ TeW “Tj“ fY P 0 ) L“X ]8lkkfe [XeXiTkXj dXjjT[X H + Up VfeVTkXeTk]e[ I, iB ’ XeVipgkXW LF + n]k“ k“X 9c]Xekffij glUc]V bXp’ I F C ’ TeW k“X XeVipgkXW j][eXW P + n]k“ LF + ) 4) L“X ]8lkkfe jXeWj k“X iXgcp dXjjT[X’ H + kf k“X 9c]Xek)

3

iButton

Client 1 P1 2 Generates RK 0 , d 0 +, p, ID log , X 0 = p, E K iB (d 0 ) _ 3 M 0 = p, ID C , PKE PK iB (RK 0 ), _  E RK 0 (X 0 , SIGN SK C (X 0 ) _ _ 4 Stores hash(X 0 ) 5 M 0 6 Retrieves RK 0 by PKD SK iB _ Retrieves X 0 by D RK 0 _ Verifies signature of X 0 Genereates RK 1 7 X 1 = p, ID log , hash(X 0 ) M 1 = p, ID iB , PKE PK C (RK 1 ), _ X  E RK 1 ( 1 , SIGN SK iB (X 1 )) _ _ 8 9 M 1 Retrieves RK 1 by PKD SK C _ Retrieves X 1 by D RK 1 _ Verifies signature of X 1 Compare hash(X 0 ) 10 W 0 = "LogfileInitializationType" D 0 = E K iB (d 0 ), d0+, ID log , M 0 _ K 0 = hash("Encryption Key", W 0 , A 0 ) Y -1 = "0000000000000000000" Y 0 = hash(Y -1 , E K 0 (D 0 ), W 0 ) _ Z 0 = MAC A0 (Y 0 ) L 0 = W 0 , E K 0 (D 0 ), Y 0,  Z 0 _ A 0 and K 0 are disposed 11 P1 12 Generates RK 2 , d 1 +, ID log X 1 = p, E K iB (d 1 ) _ 13 M 2 = p, ID C , PKE PK iB (RK 2 ), _  E RK 2 (X 1 , SIGN SK C (X 1 ) _ _ 14 Stores hash(X 1 ) 15 Time M 2 =][liX /6 L“X gifkfVfc fY ViXTk]e[ TlW]k cf[j ffljkXgj - kf -1))

Client

iButton 15 M 2 16 Retrieves RK 2 by PKD SK iB _ Retrieves X 1 by D RK 2 _ Verifies signature of X 1 Generates RK 3 17 X 2 = p, ID log , hash(X 1 ) M 3 = p, ID iB , PKE PK C (RK 3 ), _  E RK 3 (X 2 , SIGN SK iB (X 2 )) _ _ 18 19 M 3 Retrieves RK 3 by PKD SK C _ Retrieves X 2 by D RK 3 _ Verifies signature of X 2 Compare hash(X 1 ) 20 W 1 = "DRMApplicationType" D D 1 = E K_iB (d 1 ), d 1 +, I log , M 2 , Data K 1 = hash("Encryption Key", W 1 , A 1 ) Y 1 = hash(Y 0 , E K 1 (D 1 ), W 1 ) _ Z = MAC A1 (Y 1 ) 1   L 1 = W 1 , E K_1 (D 1 ), Y 1,  Z 1 A 1 and K 1 are disposed 21 P1 22 Generates RK 4 , d 2 +, ID log X 3 = p, d 2 23 M 4 = p, ID C , PKE PK iB (RK 4 ), _  E RK 4 (X 3 , SIGNS SK C (X 3 ) _ _ 24 Stores hash(X 3 ) Time =][liX 06 L“X gifkfVfc fY ViXTk]e[ TlW]k cf[j ffljkXgj -1 fenTiWj))

4

5) O“Xe k“X 9c]Xek iXVX]mXj H + Yifd k“X ]8lk( kfe’ k“X 9c]Xek mXi]ffXj k“X dXjjT[X) L“X 9c]Xek VfdgTiXj k“X “Tj“ mTclX fY P 0 Yifd k“X ]8lkkfe n]k“ k“X jkfiXW “Tj“ mTclX) -,) L“X 9c]Xek [XeXiTkXj k“X ffijk cf[ Xe( kip) L“X ffijk cf[ fflfY kpgX’ N = 00 0 GdXCZaIecZtZRaZzRtZdcTiep 00 ) dljk UX gifg( Xicp YfidXW Tk k“X 9c]Xek fi XcjX k“X KXimXi n]cc jljgXVk k“Tk k“X 9c]Xek “Tj UXXe kTd( gXiXW n]k“) L“X ffijk WTkT ffXcW’ , 0 XeVTg( jlcTkXj A K iB ffl W 0 )’ W 0 ”’ I, log ’ TeW H 0 ) L“X 9c]Xek [XeXiTkXj k“X ffijk cf[ Xekip XeVipgk]fe bXp’ F 0 ) L“XiX ]j ef giXm]flj “Tj“ mTclX kf jkTik k“X “Tj“ V“T]e j]eVX k“]j ]j k“X ffijk cf[ Xekip) L“XiXYfiX’ nX jXk k“X ]e]k]Tc “Tj“ mTclX’ Q − + kf Te TiiTp fY qXifj) BTj“ mTclX’ Q 0 ’ TeW k“X G79 mTclX’ Z TiX [XeXiTkXW) A 0 TeW F 0 0 TiX W]jgfjXW) --) K]d]cTi kf jkXg -’ kf jkTik TlW]k cf[[]e[’ k“X 9c]XekXeTUcXjP-TeWfUkT]ejTeXnTlk“Xe( k]VTk]fe bXp’ A + TeW T eXn XeVipgkXW k]dXj( kTdg’ A K iB ffl W + )) -.) L“X 9c]Xek [XeXiTkXj T eXn iTeWfd jXjj]fe bXp’ LF 0 ’ T eXn k]dXflk’ W + ”) L“X I, log ]j k“X jTdX I, log [XeXiTkXW Tk jkXg -) L“X 9c]Xek VfeVTkXeTkXj p TeW A K iB ffl W + ) TeW Yfidj P + ) -/) K]d]cTi kf jkXg /’ k“X 9c]Xek gifWlVXj dXjjT[X H 0 ) -0) K]d]cTi kf jkXg 0’ k“X 9c]Xek jkfiXj k“X “Tj“ mTclX fY P + Yfi YlkliX mTc]WTk]fe) -1) L“X 9c]Xek jXeWj dXjjT[X H 0 kf k“X ]8lkkfe) -2) L“X ]8lkkfe iXgXTkj jkXg 2) -3) L“X ]8lkkfe iXgXTkj jkXg 3) -4) L“X ]8lkkfe jXeWj k“X [XeXiTkXW dXjjT[X’ H 1 UTVb kf k“X 9c]Xek) -5) L“X 9c]Xek iXgXTkj jkXg 5 Yfi mXi]ffVTk]fe fe k“X dXjjT[Xj iXVX]mXW Yifd k“X ]8lkkfe) .,) L“X 9c]Xek iXgXTkj k“X gifVXWliXj fY [XeXi( Tk]e[ k“X ffijk cf[ Xekip ffljkXg -,) kf [Xe( XiTkX jlUjXhlXek cf[ Xeki]Xj’ n]k“ N j = 00 ,LH AppaZTRtZdcT ipe 00 ’ n“XiX j ]j k“X cf[ Xekip eldUXi) L“X fecp W]XiXeVX ]j k“Tk Tk