81 lines
1.7 KiB
Plaintext
81 lines
1.7 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) and type 2 matching (-m2)
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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 Ticket;
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usertype SessionKey;
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usertype TimeStamp;
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secret k: Function;
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usertype PseudoFunction;
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const dec: PseudoFunction;
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protocol denningSacco(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_6(I,Niagree);
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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_8(R,Niagree);
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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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# General scenario, 2 parallel runs of the protocol
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# Note because the modelchecker does not support tickets this might not
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# be very useful
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run denningSacco.I(Agent,Agent,Simon);
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run denningSacco.R(Agent,Agent,Simon);
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run denningSacco.S(Agent,Agent,Simon);
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run denningSacco.I(Agent,Agent,Simon);
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run denningSacco.R(Agent,Agent,Simon);
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run denningSacco.S(Agent,Agent,Simon);
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