89 lines
2.0 KiB
Plaintext
89 lines
2.0 KiB
Plaintext
# Paulson's strengthened version of Yahalom
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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/yahalomPaulson.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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secret k : Function;
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const Fresh: Function;
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const Compromised: Function;
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usertype SessionKey;
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protocol yahalomPaulsonSessionKeyCompromise(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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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,Ni,
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R,Nr,{I,Ni}k(R,S),
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Nr,{R,Kir,Ni}k(I,S),
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{I,R,Kir,Nr}k(R,S),
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{Nr}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 yahalomPaulson(I,R,S)
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{
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role I
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{
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const Ni: Nonce;
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var Nr: Nonce;
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var T: Ticket;
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var Kir: SessionKey;
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send_1(I,R, I,Ni);
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read_3(S,I, Nr, {R,Kir,Ni}k(I,S), T );
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send_4(I,R, T, {Nr}Kir );
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claim_I1(I, Secret,Kir);
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claim_I2(I, Nisynch);
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claim_I3(I, Empty, (Fresh,Kir));
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}
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role R
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{
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const Nr: Nonce;
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var Ni: Nonce;
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var T: Ticket;
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var Kir: SessionKey;
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read_1(I,R, I,Ni);
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send_2(R,S, R, Nr, {I,Ni}k(R,S) );
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read_4(I,R, {I,R, Kir, Nr}k(R,S) , {Nr}Kir );
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claim_R1(R, Secret,Kir);
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claim_R2(R, Nisynch);
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claim_R3(R, Empty, (Fresh,Kir));
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}
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role S
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{
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const Kir: SessionKey;
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var Ni,Nr: Nonce;
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read_2(R,S, R, Nr, {I,Ni}k(R,S) );
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send_3(S,I, Nr, {R,Kir,Ni}k(I,S), {I,R,Kir,Nr}k(R,S) );
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}
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}
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const Alice,Bob,Simon : Agent;
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run yahalomPaulson.I(Agent,Agent,s);
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run yahalomPaulson.I(Agent,Agent,s);
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run yahalomPaulson.R(Agent,Agent,s);
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