Elements of Security Protocols Secure Socket Layer (SSL)

Network Security Elements of Security Protocols Secure Socket Layer (SSL)!!"#$%&'&&(")! *+,-".&.#.++.,/'#."0! *+,-".&.#.++.,1)203$)4'! 5&%+%66.,0%,778,2'%,-)9):'2&%,'+'&&".2%#%! 8%:%&%,0%,778 Sicurezza nella pila TCP/IP )''" $*'" +'" )''" $*'" +'" $$,-.',$ '(" '("!"#!"$%&!" 4+/5+/.6 "2" $1' $*'" )''" /0" '("!" 3.456%447.8%9% 3.456%447.983:;7897 3.456%447.3;;45&3<57=% 3

La suite di protocolli SSL!--+%#)6%.2% ;".&.#.++., 1)203$)4' ;".&.#.++., <$)29',<%-$'" ;".&.#.++.,!+'"& 1==; ;".&.#.++.,/'#."0 =<; *; 7 Riferimenti! 7'#("',7.#4'&,8)>'",?778@!!"#$%&&'&#()'(*%&+,'-%!.&&-/001-23%&+,'-%2,#40%3$0++560! =")23-."&,8)>'",7'#("%&>,?=87@! 7'+'&#(+8(99:(;62<! =>?(@@AB! C&-/00C&-2"C,D%)E&#"2#"$0E3D3#&%+0"C,@@AB2&F& 8

Sessione e connessione $%::57=% &7==%::57=% (45%=9% $%86%8! :'(+%++E#3%(G(!"#$%%&'($)(&"*+,&-('$+&"'(?5E%3&%(%(9%";%"2(! H3'(+%++E#3%(;E%3%(,"%'&'()'5(-"#&#,#55#()E(1)203$)4' %( )%CE3E+,%(83(E3+E%4%()E(.$/$0*1/(+'/(11&-/$2('(+,.%(-#++#3#( %++%"%(,#3)E;E+E(C"'(4#5&%-5E,E(,#33%++E#3E2! :'(+%++E#3%(%;E&'(5'(,#+&#+'("E3%$#IE'IE#3%()%E(-'"'4%&"E()E( +E,8"%II'(-%"(,E'+,83'(,#33%++E#3%( 9 Sessione e connessione 1+66".$+ '.$$+66".$+ ;%"+$,+ 1+/<+/ 7=!=A,B*,5C!,7D77*ACD! *0'2&%E%#)&."',0%,3'33%.2' J+%++E#3(E)%3&ECE%"K! <'"&%E%#)&. 0'+,-''",?FGHIJKL@,! M'&.0.,0%,#.:-"'33%.2' J#.:-"'33%.2,:'&$.0K(! <%E")"%.,'0,)+9."%&:.,$)3$ J#%-$'",3-'#K! 7'9"'&.,-"%2#%-)+' J:)3&'",3'#"'&K(LAM(7E&N O8%+&E(;'5#"E()%CE3E+,#3#(5#(+&'&#()E(,E'+,83(*"3.&("1 )%55'(+%++E#3% :

Sessione e connessione 1+66".$+ ;%"+$,+ 1+/<+/ '.$$+66".$+ STATO DI UNA CONNESSIONE! Server random number (nonce)! Client random number (nonce)! Server write MAC secret! Client write MAC secret! Server write key! Client write key! Initialization vectors! Sequence numbers = Il Protocollo Record ;3>473? @83AA%=93<57=% &7A;8%::57=% 3BB5C=93.?%4.*D( &5@839C83 Il Protocollo Record incapsula i dati spediti dai livelli superiori assicurando la "#$%&'($)&*+&,-.(.+/&$,(01&,-. della comunicazione 3;;7:5<57=%.?%443 5=9%:93<57=% >

Il Protocollo Record! :'(2/$00*"1$)(&"* C"'44%3&'(E()'&E('--5E,'&E;E(E3(75#,,.E()E('5(-EP(@ QA( 7R&%! :'('&0./*%%(&"* )%;%(%++%"%( +%3I'(-%")E&'(%( 3#3()%;%(C'"('84%3&'"%(5%()E4%3+E#3E()E(83(75#,,#()E(-EP()E(Q<@A(7R&%( J)%C'85&(S(3855K! T5(456 8&E5EII'(E5(N7'"K'"" <+%'2&O,P"%&',M!<,3'#"'&U(E5(+%V8%3,%(3847%"U(E5( "#$%%$&%$'()*++$,&(-.,/! :'('(2/$1!/$ 8&E5EII'(5'(N7'"K'"" <+%'2&O,P"%&',4'> -8W(%++%"%('(75#,,.E(#('(,'"'&&%"E(%( 3#3()%;%(C'"('84%3&'"%(5%()E4%3+E#3E()E(83(75#,,#()E(-EP()E(Q<@A(7R&%? Il Protocollo Record! *2&'3&)6%.2'! =%-.,0%,-)>+.)0 J,.'3$%(,E-.%"U('5%"&U(.'3)+.'X%U( '--5E,'&E#3K! Q'"3%.2',-"%2#%-)+'! Q'"3%.2',:%2."'! 8(29$'66),#.:-"'33) J# @ QA Y(@<AMK *+,-./0(1+'&/",2!!"#$%&'#()"$" @A

Tipi di payload EF>9% EF>9% HF>9% $ IF>9% E 95;7 4C=BG%<<3 &7=9%=C97 "8797&7447. (G3=B%.(5;G%8 "8797&7447. )3=?:G3J% EF>9% 456%447 EF>9% 34438A% $ IF>9% (7=9%=C97.7;3&7 "8797&7447. D4%89 "8797&7447.!""#$%&'$()*+,--./01 *+,-./0(1+'&/",2!!"#$%&'#()"$" @@ Il Protocollo Handshake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` @3

Protocollo Handshake: schema di principio (1) &45%=9 :%86%8 K$D 1=&8>;957= L%9M78J K$D 0%&8>;957= pre-master secret (48 byte) utilizzato per cifrare le successive comunicazioni @7 Protocollo Handshake: schema di principio (2) solo autenticazione del server &45%=9 :%86%8 &45%=9.=7=&% :%86%8.=7=&% @B('%"+$,CD+%%. 3B(6+/<+/CD+%%. &45%=9.=7=&% :%86%8.=7=&% 7B('+/,"E"'#,+ 8B(6+/<+/CD+%%.CF.$+ ;8%NA3:9%8 :%&8%9 K$D 1=&8>;957= K$D 0%&8>;957= ;8%NA3:9%8. :%&8%9 @8

I messaggi di Hello! 7"+8!*%1$+2$%*+(,+',(*"1+*3+(,+%*/9*/+%(+3('&"&+'&%$+%$""&+2$/*+("&,1/*+ (,+',(*"1+$!1*"1('$+(,+%*/9*/! M'33)99%.,#+%'2&R$'++.,',3'"K'"R$'++.! Q'"3%.2' )E(99:(! /)20.:/(&E4%+&'4-(J6@(7E&K(Y("'3)#4(7R&%L@MN[(,5E%3&(%(+%";%"($%3%"'3#(V8'3&E&`( "'3)#4()E;%"+%! *B,0%,3'33%.2'/(E3(7'+%('5(;'5#"%(JQK(;E%3%(,"%'&'(83'(38#;'(+%++E#3%U(J@K(;E%3%(,"%'&'(83'(,#33%++E#3%(E3(83'(+%++E#3%(%+E+&%3&%(J6K(;%3$#3#("E3%$#IE'&E(E( -'"'4%&"E()E(83'(+%++E#3%(%+E+&%3&%! 7(%&',0%,#%E")&(") J<%-$'",3(%&'K(+-%,ECE,'(5'(5E+&'()%$5E('5$#"E&4E()E(,EC"'&8"'( +8--#"&'&E()'5(,5E%3&%(E3(#")E3%()E($"')E4%3&#[(E5(+%";%"(+,%$5E%! M'&.0.,0%,#.:-"'33%.2'/(5E+&'()%E(4%&#)E()E(,#4-"%++E#3%(+8--#"&'&E()'5(,5E%3&[( E5(+%";%"(+,%$5E% @9 Cipher Suite! :'(#%-$'",3(%&' +-%,ECE,'(83'(5E+&'()E(&%"3%()E('5$#"E&4E %7#):S%.,#$%)K%T,<%E")"%.T,M!<& '5,83%()E(V8%+&%(&%"3%(+#3#(+&'&%(+&'3)'")EII'&% 778R/7!RU*=1RLBD7RDBDR<V<R71!! T(4%&#)E()E(+,'47E#()%55%(,.E';E(+8--#"&'&E(+#3#/! =9^(J%3,"R-&E#3K! >EF%)(aECCE%DZ%554'3( JE(-'"'4%&"E(-8775E,E(+#3#(CE++E(%(,%"&ECE,'&EK! b-.%4%"'5(aecce%dz%554'3( JE(-'"'4%&"E(-8775E,E(+#3#(,"%'&E()E(;#5&'(E3(;#5&'(%(CE"4'&EK! ^3#3R4#8+(aECCE%DZ%554'3( J+%3I'('8&%3&E,'IE#3%K! /! 0&%12)-)1&+3(($)4-41&+$5$6&789,&78:,&;<=,&>;<=,&0;<?,&/! T(]^?(+8--#"&'&E(+#3#/(]acU(9Z^DQ *+,-./0(1+'&/",2!!"#$%&'#()"$" @:

Generazione delle chiavi lato server e lato client nei rispettivi messaggi di 1'++.?395.;8%?%@5=595 ;8%NA3:9%8.:%&8%9 &45%=9.=7=&% :%86%8.=7=&%!"%D4'+&%"(+%,"%&(G(8&E5EII'&#(,#4%( %&/-*"1*+3(+*"1/&.($ )3:G.*C495N:9%; $%86%8.M859%.*D(.:%&8%9. (45%=9.M859%.*D(.:%&8%9.. J%>.F47&J $%86%8.M859%.J%>... (45%=9.M859%.J%>... &#'2)0********* *+,-./0(1+'&/",2!!"#$%&'#()"$" @= Protocollo Handshake: schema di principio (3) &45%=9 :%86%8 &45%=9.M859%. J%> GOP 1OP &45%=9.=7=&% :%86%8.=7=&% ;8%NA3:9%8.:%&8%9 :%86%8.&%895@5&39% GOP &45%=9Q@5=5:G%? :%86%8Q@5=5:G%? :%86%8.M859% J%> 'D#$G+C'"HD+/C6H+' '%"+$,CE"$"6D+F &45%=9 M859%.J%> GOP 0OP R &45%=9.=7=&% :%86%8.=7=&% ;8%NA3:9%8.:%&8%9 :%86%8.&%895@5&39% &45%=9Q@5=5:G%? :%86%8Q@5=5:G%? GOP R 0OP 'D#$G+C'"HD+/C6H+' 6+/<+/CE"$"6D+F 1OP :%86%8.M859% J%> *+,-./0(1+'&/",2!!"#$%&'#()"$" @>

Autenticazione del client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cQ@(7E&K(E3;%,%()%E(Q@M(7E&( +8--#"&'&E()'E(7"#1+%"(-EP("%,%3&E! T(;%,,.E(7"#1+%"(+#3#('3,#"'(E3(8+#[(4#5&E(8&%3&E(+#3#(E$3'"E()%5(-"#75%4'! 778,3(--."&),)2#$',+Z)(&'2&%#)6%.2',0'+,#+%'2&,"%3-'&&.,)+,3'"K'" *+,-./0(1+'&/",2!!"#$%&'#()"$" @? Autenticazione del client: schema di principio (3) '%"+$,! T5(+%";%"("E,.E%)%(5\'8&%3&E,'IE#3%()%5(,5E%3&(,#3(83(4%++'$$E#( #'"&%E%#)&',"'[('3& )#-#(3'"K'"R$'++.! :\'8&%3&E,'IE#3%(G()E(&E-#(':$,,*"-*;/*%.&"%* &45%=9.&%895@5&39% :%86%8.&%895@5&39% &45%=9.=7=&% :%86%8.=7=&% ;8%NA3:9%8.:%&8%9 GOP 'D#%%+$G+ '+/,"E"'#,+ 6+/<+/ &45%=9.;85639%. J%> +58A3.?5B5934% OK$DP /+6H.$6+ '+/,"E"'#,+(<+/"E2 *+,-./0(1+'&/",2!!"#$%&'#()"$" 3A

Sicurezza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rotocollo Handshake: formato dei messaggi TIPO CONTENUTO hello_request client_hello server_hello certificate server_key_exchange certificate_request server_hello_done certificate_verify client_key_exchange finished nessun paramentro Versione, random, ID di sessione, suite di cifratura, metodo di compressione Versione, random, ID di sessione, suite di cifratura, metodo di compressione Catena di certificati X.509v3 Parametri, firma Tipo, autorità Nessun parametro Firma Parametri, firma Valore hash 33

2.31#,#"#++&.4*$'56*7(8.9&5&#$(.'/&$5&(:( CLIENT Client hello Pre-master secret Certificato del client* Finished Scambio sicuro dei dati HANDSHAKE RECORD Server hello Certificato del server Richiesta del certificato del client* Server hello done Finished SERVER Scambio sicuro dei dati 37 2+.;1#,#"#++#.4*$'56*7(8.9&5&#$(.'/&$5&(:( (45%=9 A%::3BB5.7;<57=345 $%86%8 @(/.&$F 0%@5=5<57=%.?%44%.&3;3&59S.?5.:5&C8%<<3 3(/.&$F DC9%=95&3<57=%.?%4.:%86%8 7(/.&$F DC9%=95&3<57=%.?%4.&45%=9 8(/.&$F (7=&4C:57=% 38

Gli altri protocolli di SSL! T5(-"#&#,#55#(#$)29' #%-$'" 3-'#,G(,#+&E&8E&#()'(83(+#5#(4%++'$$E#(JE3(,.E'"#K(,.%(.'(,#4%(#7E%&&E;#(V8%55#()E("%3)%"%(#-%"'&E;'(5'(,E-.%" +8E&%( 3%$#IE'&'! T5(-"#&#,#55#()+'"& G(8&E5EII'&#(-%"(,#483E,'"%('5(-%%" E(4%++'$$E()E( '55'"4%("%5'&E;E('(99:/ 83%F-%,&%)d4%++'$% 7')d"%,#") 4', )%,#4-"%++E#3dC'E58"%.'3)+.'X%dC'E58"% E55%$'5d-'"'4%&%" 3#d,%"&ECE,'&% 7')d,%"&ECE,'&% 83+8--#"&%)d,%"&ECE,'&%,%"&ECE,'&%d"%;#X%),%"&ECE,'&%d%F-E"%),%"&ECE,'&%d83X3#13 39 Il certificato è quello giusto? ---B#EE#/"B'.I!"#$%"&' ^5E,%(J99:K(;%"ECE,'(,#3(+8,,%++#(E5(,%"&ECE,'&#( )%55'(7'3,'U(+&'7E5E+,%(5'(,#33%++E#3%(%)(E3;E'( 5'(-"#-"E'(!ea('55'(7'3,' ---B5#$0B'.I 3:

Il certificato è quello giusto? ---BG/#$F"#EE#/"B'.I!"#$%"&' ^5E,%(J99:K(;%"ECE,'(,#3(+8,,%++#(E5(,%"&ECE,'&#( )%55\';;%"+'"E#U(+&'7E5E+,%(5'(,#33%++E#3%(%)( E3;E'(5'(-"#-"E'(!ea('55'(7'3,' ---B5#I0B'.I 3= Il certificato è quello giusto?! Il problema è che SSL opera ad un livello più basso di quello applicativo! È l'applicazione che deve (indurre l'utente a) verificare che il nome richiesto sia uguale al nome contenuto nel certificato verificato! ESEMPIO: Netscape! Il browser notifica all'utente se l'url specificato dal browser e quello contenuto nel certificato del server sono diversi! L'utente decide se proseguire la connessione oppure no (interfaccia utente!!!)! In linea di principio non è detto che il controllo eseguito dal browser Netscape sia sufficiente per ogni tipo di applicazione Web-based 3>

Acquisti in rete con SSL $$, =8T.UVWI.EXHV.UYZ[.6345?.9G8C.II#II!!4.=CA%87.?%443.&3893.=7=. \.C=]5=@78A3<57=%.:%B8%93!!4.A599%=9%.\.;87;857. K5&G38?.(87:M%44^ 3 K7B39785%.5=9%8=3<57=345 3 D=345:5.?%5.47B 3 $;77@5=B-.;5=BN")45/0 3? Acquisti in rete mediante carta di credito )+'/+,.(%+G"6%#,"<.(33(I#GG".(@???J($B(@>9J(F"( #,,&#K".$+(F+%%# F"/+,,"<#?=L=L;M N/,B(>(O P#G#I+$,.(I+F"#$,+('#/,# ET.!4.&7=:CA3978%.;C_.%@@%99C38%.54.;3B3A%=97.A%?53=9%.&3893.76%.&5_.:53. ;8%65:97.983.4%.A7?3459S.?5.;3B3A%=97-.?3.&7AC=5&38%.34.&7=:CA3978%.34. :%=:5.?%44]3895&747.H-.&7AA3.E-.4%99%83.%P-.?%4.;8%:%=9%.?%&8%97.4%B5:439567T XT.,]5:959C97.?5.%A5::57=%.?%443.&3893.?5.;3B3A%=97.853&&8%?593.34. &7=:CA3978%.5.;3B3A%=95.?%5.`C345.`C%:95.?5A7:985.4]%&&%?%=<3.85:;%997.34. ;8%<<7.;399C597.766%87.4]%@@%99C3<57=%.A%?53=9%.4]C:7.@83C?74%=97.?%443. ;87;853.&3893.?5.;3B3A%=97.?3.;389%.?%4.@78=5978%.7.?5.C=.9%8<7-.@3993.:3463. 4]3;;45&3<57=%.?%44]3895&747.EX.?%4.?%&8%97N4%BB%.H.A3BB57.EWWE-.=T.EVH-. &7=6%89597-.&7=.A7?5@5&3<57=5-.?3443.4%BB%.U.4CB457.EWWE-.=T.EWZT.,]5:959C97.?5. %A5::57=%.?%443.&3893.?5.;3B3A%=97.G3.?585997.?5.3??%F5938%.34.@78=5978%.4%. :7AA%.853&&8%?5939%.34.&7=:CA3978%T *+,-./0(1+'&/",2!!"#$%&'#()"$" 7A

Acquisti in rete mediante carta di credito!%"("6,",&,"(f"(+i"66".$+-.&c5.&7a;%9%.4]3c9785<<3<57=%.?%44]7;%83<57=%.?5.;3b3a%=97-.=7=&ga.5.:7bb%995.&g%.8%=?7=7. 9%&=5&3A%=9%.;7::5F54%.43.983=:3<57=%.7=N45=%-.6.$.(,+$&,"(#( '.$,/.%%#/+(%#('.//+,,+KK#(F+%($&I+/.(F+%%#('#/,#(+(%#(F#,#( F+%%#(6&#(6'#F+$K# I#($.$(#$'D+(%#('.//"6H.$F+$K#(,/#("%( $&I+/.(E./$",.(+(%Q+EE+,,"<.(,",.%#/+ 245.5:959C95.?5.%A5::57=%.6%85@5&3=7.43.&7885:;7=?%=<3.983.=CA%87.?%443. &3893.?5.&8%?597.&7AC=5&397.;%8.%@@%99C38%.C=3.983=:3<57=%.7=N45=%.%?. 54.=7A5=39567.@78=597.?3.&74C5.&G%.43.%@@%99C3T. D?.%:%A;57-.4]D??8%::.b%85@5&3957=.$%865&%.ODb$P.6%85@5&3.&G%. 4]5=?585<<7.?5.&7=:%B=3.:53.`C%447.&7=.&C5.54.;7::%::78%.?%443.&3893.\. 8%B5:98397!=.1C87;3.54.B83?7.?5.:5&C8%<<3.=%44%.983=:3<57=5.7=N45=%.\.A5=78%.%. `C5=?5.54.&7AA%8&57.%4%9987=5&7.\.?%:95=397.3?.5=&7=9838%.8%:5:9%=<%. 3=&G%.?3.;389%.?%5.@78=59785.?5.&G%.:7;;7893=7.85:&G5.%4%6395 7@ Acquisti in rete mediante carta di credito!4.@78=5978%.?5.f%=5.7.:%865<5.7=n45=%.r(,+$&,.(#f(#''.%%#/6"("%( /"6'D".?%443.85634:3.?%B45.5:959C95.?5.%A5::57=%.`C34783-.5=.&3:7.?5.C:7. @83C?74%=97.?%44%.&3893-.`C%:95.853&&8%?593=7.4%.&7885:;7=?%=95.:7AA%. 34.4%B5995A7.9597438%T,3.4%BB%.$.$('.$6+$,+ &#*6)24$')27*8$*#$972&2:$*8&##;)99#$5)*87##&* 8%:959C<57=%.?%44%.:7AA%.3B45.5:959C95.?5.%A5::57=%.`C34783.?5A7:985. ET XT?5.36%8%.C:397.9C99%.4%.&3C9%4%.=%&%::385%.%.;7::5F545.3?.%65938%. #;<:)*62&<8)#74')*87##&*%&2'&*8$*%278$')* &G%.54.@3997.\.:9397.&3C:397.?34.&3:7.@789C597T.!.@78=59785.?7683==7.C:38%.9C99%.4%.&3C9%4%.?%4.&3:7.;%8.;79%8%-.=%4. &3:7.?5.C:7.@83C?74%=97.?5.&389%.?5.&8%?597-.;%847A%=7.85=983&&538%. #;$##75$''$=)*<'$#$>>&')27*7*2$(&#72:$*:<*?<7:')@* A7*%)4:75<74>7*872$(&4'$*8&##;&8879$')*87##7*:)==7*2$&%%278$'&'7*&#* 9597438%.?%443.&3893.;798%FF%87.;75.%::%8%.3==C4439%.&7=983%=?7.C=3. 3::5&C83<57=%.3.&7;%89C83.?%5.?3==5.O%&7=7A5&5P.?%8563=95.?3.934%. &58&7:93=<3T. 73

Acquisti in rete con SSL +7B457.5=@78A39567.:C44%.7;%83<57=5.%.:%865<5.7@@%895.3443.&45%=9%43. O&385;8397P 77 Acquisti in rete con SSL 78

Limiti di SSL!!!"#$#%&#'()*)+),,)#-.+%()#/0&#'()10**2*)#+30#%*.,.442#2,1)(.*5.# -.+%(.#0#()/%-*.!!!"#'0(6#'(0-0&*2#.#-01%0&*.#,.5.*.! 5\8&%3&%(.'(5\#3%"%()E(,#3&"#55'"%(5%(E3C#"4'IE#3E()E(+E,8"%II'! 99:(G(;853%"'7E5%('55#(+-##CE3$()%E(3#4E! 99:(-"#&%$$%(+#5#(5'(,#483E,'IE#3% 79