101 lines
2.3 KiB
Plaintext
101 lines
2.3 KiB
Plaintext
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# Lowe modified Denning-Sacco shared key
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#
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# Modelled after the description in the SPORE library
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# http://www.lsv.ens-cachan.fr/spore/denningSaccoLowe.html
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#
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# Note:
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# This protocol uses a ticket so scyther will only be able to verify
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# the protocol using the ARACHNE engine (-a)
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#
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# Note:
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# According to SPORE there are no attacks on this protocol, scyther
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# finds one however. This has to be investigated further.
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usertype Key;
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usertype SessionKey;
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usertype TimeStamp;
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usertype ExpiredTimeStamp;
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secret k: Function;
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usertype PseudoFunction;
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const dec: PseudoFunction;
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const Fresh: Function;
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const Compromised: Function;
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protocol denningSacco-Lowe^KeyCompromise(C)
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{
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// Read the names of 3 agents and disclose a session between them including
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// corresponding session key to simulate key compromise
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role C {
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const Ni,Nr: Nonce;
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const Kir: SessionKey;
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const T: ExpiredTimeStamp;
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var I,R,S: Agent;
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read_C1(C,C, I,R,S);
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send_C2(C,C, (I,R),
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{R,Kir,T,{Kir,I,T}k(R,S)}k(I,S),
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{Kir,I,T}k(R,S),
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{Nr}Kir,
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{{Nr}dec}Kir,
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Kir
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);
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claim_C3(C,Empty, (Compromised,Kir));
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}
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}
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protocol denningSacco-Lowe(I,R,S)
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{
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role I
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{
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var W: Ticket;
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var Kir: SessionKey;
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var T: TimeStamp;
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var Nr: Nonce;
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send_1(I,S, I,R );
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read_2(S,I, {R, Kir, T, W}k(I,S) );
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send_3(I,R, W);
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read_4(R,I, {Nr}Kir);
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send_5(I,R, {{Nr}dec}Kir);
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claim_I1(I,Niagree);
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claim_I2(I,Nisynch);
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claim_I3(I,Secret,Kir);
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claim_I4(I,Empty,(Fresh,Kir));
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}
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role R
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{
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var Kir: SessionKey;
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var T: TimeStamp;
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const Nr: Nonce;
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read_3(I,R, {Kir,I,T}k(R,S));
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send_4(R,I, {Nr}Kir);
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read_5(I,R, {{Nr}dec}Kir);
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claim_R1(R,Niagree);
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claim_R2(R,Nisynch);
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claim_R3(R,Secret,Kir);
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claim_R4(R,Empty,(Fresh,Kir));
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}
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role S
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{
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var W: Ticket;
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const Kir: SessionKey;
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const T: TimeStamp;
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read_1(I,S, I,R );
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send_2(S,I, {R, Kir, T, {Kir, I,T}k(R,S)}k(I,S));
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}
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}
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const Alice,Bob,Simon,Eve: Agent;
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untrusted Eve;
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const kee: SessionKey;
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const tee: TimeStamp;
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compromised k(Eve,Simon);
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