From a6a8784e5ad940e48dec6b14d361e44901cd4ef9 Mon Sep 17 00:00:00 2001 From: sjunges Date: Thu, 17 Nov 2016 15:03:31 +0100 Subject: [PATCH] general crowds dtmc added Former-commit-id: c2a9dd68faddda607cb17fc5e9f25559ea38480d [formerly b95a014e013bd6dd83bbebfb195cacaca0702cb0] Former-commit-id: 4cd7ebe441a1622b701e7f2807cb2b0a20bfe756 --- examples/dtmc/crowds/crowds.pm | 177 +++++++++++++++++++++++++++++++++ 1 file changed, 177 insertions(+) create mode 100644 examples/dtmc/crowds/crowds.pm diff --git a/examples/dtmc/crowds/crowds.pm b/examples/dtmc/crowds/crowds.pm new file mode 100644 index 000000000..53eb7b75e --- /dev/null +++ b/examples/dtmc/crowds/crowds.pm @@ -0,0 +1,177 @@ +// CROWDS [Reiter,Rubin] +// Vitaly Shmatikov, 2002 + +// Note: +// Change everything marked CWDSIZ when changing the size of the crowd +// Change everything marked CWDMAX when increasing max size of the crowd + +dtmc + +// Probability of forwarding +const double PF = 0.8; + +// Probability that a crowd member is bad +const double badC = 0.091; +// const double badC = 0.167; + +const int TotalRuns; // Total number of protocol runs to analyze +const int CrowdSize; // CWDSIZ: actual number of good crowd members +const int MaxGood=20; // CWDMAX: maximum number of good crowd members + +// Process definitions +module crowds + + // Auxiliary variables + launch: bool init true; // Start modeling? + new: bool init false; // Initialize a new protocol instance? + runCount: [0..TotalRuns] init TotalRuns; // Counts protocol instances + start: bool init false; // Start the protocol? + run: bool init false; // Run the protocol? + lastSeen: [0..MaxGood] init MaxGood; // Last crowd member to touch msg + good: bool init false; // Crowd member is good? + bad: bool init false; // ... bad? + recordLast: bool init false; // Record last seen crowd member? + badObserve: bool init false; // Bad members observes who sent msg? + deliver: bool init false; // Deliver message to destination? + done: bool init false; // Protocol instance finished? + + // Counters for attackers' observations + // CWDMAX: 1 counter per each good crowd member + observe0: [0..TotalRuns] init 0; + observe1: [0..TotalRuns] init 0; + observe2: [0..TotalRuns] init 0; + observe3: [0..TotalRuns] init 0; + observe4: [0..TotalRuns] init 0; + observe5: [0..TotalRuns] init 0; + observe6: [0..TotalRuns] init 0; + observe7: [0..TotalRuns] init 0; + observe8: [0..TotalRuns] init 0; + observe9: [0..TotalRuns] init 0; + observe10: [0..TotalRuns] init 0; + observe11: [0..TotalRuns] init 0; + observe12: [0..TotalRuns] init 0; + observe13: [0..TotalRuns] init 0; + observe14: [0..TotalRuns] init 0; + observe15: [0..TotalRuns] init 0; + observe16: [0..TotalRuns] init 0; + observe17: [0..TotalRuns] init 0; + observe18: [0..TotalRuns] init 0; + observe19: [0..TotalRuns] init 0; + + [] launch -> (new'=true) & (runCount'=TotalRuns) & (launch'=false); + // Set up a new protocol instance + [] new & runCount>0 -> (runCount'=runCount-1) & (new'=false) & (start'=true); + + // SENDER + // Start the protocol + [] start -> (lastSeen'=0) & (run'=true) & (deliver'=false) & (start'=false); + + // CROWD MEMBERS + // Good or bad crowd member? + [] !good & !bad & !deliver & run -> + 1-badC : (good'=true) & (recordLast'=true) & (run'=false) + + badC : (bad'=true) & (badObserve'=true) & (run'=false); + + // GOOD MEMBERS + // Forward with probability PF, else deliver + [] good & !deliver & run -> PF : (good'=false) + 1-PF : (deliver'=true); + // Record the last crowd member who touched the msg; + // all good members may appear with equal probability + // Note: This is backward. In the real protocol, each honest + // forwarder randomly chooses the next forwarder. + // Here, the identity of an honest forwarder is randomly + // chosen *after* it has forwarded the message. + [] recordLast & CrowdSize=2 -> + 1/2 : (lastSeen'=0) & (recordLast'=false) & (run'=true) + + 1/2 : (lastSeen'=1) & (recordLast'=false) & (run'=true); + [] recordLast & CrowdSize=4 -> + 1/4 : (lastSeen'=0) & (recordLast'=false) & (run'=true) + + 1/4 : (lastSeen'=1) & (recordLast'=false) & (run'=true) + + 1/4 : (lastSeen'=2) & (recordLast'=false) & (run'=true) + + 1/4 : (lastSeen'=3) & (recordLast'=false) & (run'=true); + [] recordLast & CrowdSize=5 -> + 1/5 : (lastSeen'=0) & (recordLast'=false) & (run'=true) + + 1/5 : (lastSeen'=1) & (recordLast'=false) & (run'=true) + + 1/5 : (lastSeen'=2) & (recordLast'=false) & (run'=true) + + 1/5 : (lastSeen'=3) & (recordLast'=false) & (run'=true) + + 1/5 : (lastSeen'=4) & (recordLast'=false) & (run'=true); + [] recordLast & CrowdSize=10 -> + 1/10 : (lastSeen'=0) & (recordLast'=false) & (run'=true) + + 1/10 : (lastSeen'=1) & (recordLast'=false) & (run'=true) + + 1/10 : (lastSeen'=2) & (recordLast'=false) & (run'=true) + + 1/10 : (lastSeen'=3) & (recordLast'=false) & (run'=true) + + 1/10 : (lastSeen'=4) & (recordLast'=false) & (run'=true) + + 1/10 : (lastSeen'=5) & (recordLast'=false) & (run'=true) + + 1/10 : (lastSeen'=6) & (recordLast'=false) & (run'=true) + + 1/10 : (lastSeen'=7) & (recordLast'=false) & (run'=true) + + 1/10 : (lastSeen'=8) & (recordLast'=false) & (run'=true) + + 1/10 : (lastSeen'=9) & (recordLast'=false) & (run'=true); + [] recordLast & CrowdSize=15 -> + 1/15 : (lastSeen'=0) & (recordLast'=false) & (run'=true) + + 1/15 : (lastSeen'=1) & (recordLast'=false) & (run'=true) + + 1/15 : (lastSeen'=2) & (recordLast'=false) & (run'=true) + + 1/15 : (lastSeen'=3) & (recordLast'=false) & (run'=true) + + 1/15 : (lastSeen'=4) & (recordLast'=false) & (run'=true) + + 1/15 : (lastSeen'=5) & (recordLast'=false) & (run'=true) + + 1/15 : (lastSeen'=6) & (recordLast'=false) & (run'=true) + + 1/15 : (lastSeen'=7) & (recordLast'=false) & (run'=true) + + 1/15 : (lastSeen'=8) & (recordLast'=false) & (run'=true) + + 1/15 : (lastSeen'=9) & (recordLast'=false) & (run'=true) + + 1/15 : (lastSeen'=10) & (recordLast'=false) & (run'=true) + + 1/15 : (lastSeen'=11) & (recordLast'=false) & (run'=true) + + 1/15 : (lastSeen'=12) & (recordLast'=false) & (run'=true) + + 1/15 : (lastSeen'=13) & (recordLast'=false) & (run'=true) + + 1/15 : (lastSeen'=14) & (recordLast'=false) & (run'=true); + [] recordLast & CrowdSize=20 -> + 1/20 : (lastSeen'=0) & (recordLast'=false) & (run'=true) + + 1/20 : (lastSeen'=1) & (recordLast'=false) & (run'=true) + + 1/20 : (lastSeen'=2) & (recordLast'=false) & (run'=true) + + 1/20 : (lastSeen'=3) & (recordLast'=false) & (run'=true) + + 1/20 : (lastSeen'=4) & (recordLast'=false) & (run'=true) + + 1/20 : (lastSeen'=5) & (recordLast'=false) & (run'=true) + + 1/20 : (lastSeen'=6) & (recordLast'=false) & (run'=true) + + 1/20 : (lastSeen'=7) & (recordLast'=false) & (run'=true) + + 1/20 : (lastSeen'=8) & (recordLast'=false) & (run'=true) + + 1/20 : (lastSeen'=9) & (recordLast'=false) & (run'=true) + + 1/20 : (lastSeen'=10) & (recordLast'=false) & (run'=true) + + 1/20 : (lastSeen'=11) & (recordLast'=false) & (run'=true) + + 1/20 : (lastSeen'=12) & (recordLast'=false) & (run'=true) + + 1/20 : (lastSeen'=13) & (recordLast'=false) & (run'=true) + + 1/20 : (lastSeen'=14) & (recordLast'=false) & (run'=true) + + 1/20 : (lastSeen'=15) & (recordLast'=false) & (run'=true) + + 1/20 : (lastSeen'=16) & (recordLast'=false) & (run'=true) + + 1/20 : (lastSeen'=17) & (recordLast'=false) & (run'=true) + + 1/20 : (lastSeen'=18) & (recordLast'=false) & (run'=true) + + 1/20 : (lastSeen'=19) & (recordLast'=false) & (run'=true); + + // BAD MEMBERS + // Remember from whom the message was received and deliver + // CWDMAX: 1 rule per each good crowd member + [] lastSeen=0 & badObserve & observe0 (observe0' =observe0 +1) & (deliver'=true) & (run'=true) & (badObserve'=false); + [] lastSeen=1 & badObserve & observe1 (observe1' =observe1 +1) & (deliver'=true) & (run'=true) & (badObserve'=false); + [] lastSeen=2 & badObserve & observe2 (observe2' =observe2 +1) & (deliver'=true) & (run'=true) & (badObserve'=false); + [] lastSeen=3 & badObserve & observe3 (observe3' =observe3 +1) & (deliver'=true) & (run'=true) & (badObserve'=false); + [] lastSeen=4 & badObserve & observe4 (observe4' =observe4 +1) & (deliver'=true) & (run'=true) & (badObserve'=false); + [] lastSeen=5 & badObserve & observe5 (observe5' =observe5 +1) & (deliver'=true) & (run'=true) & (badObserve'=false); + [] lastSeen=6 & badObserve & observe6 (observe6' =observe6 +1) & (deliver'=true) & (run'=true) & (badObserve'=false); + [] lastSeen=7 & badObserve & observe7 (observe7' =observe7 +1) & (deliver'=true) & (run'=true) & (badObserve'=false); + [] lastSeen=8 & badObserve & observe8 (observe8' =observe8 +1) & (deliver'=true) & (run'=true) & (badObserve'=false); + [] lastSeen=9 & badObserve & observe9 (observe9' =observe9 +1) & (deliver'=true) & (run'=true) & (badObserve'=false); + [] lastSeen=10 & badObserve & observe10 (observe10'=observe10+1) & (deliver'=true) & (run'=true) & (badObserve'=false); + [] lastSeen=11 & badObserve & observe11 (observe11'=observe11+1) & (deliver'=true) & (run'=true) & (badObserve'=false); + [] lastSeen=12 & badObserve & observe12 (observe12'=observe12+1) & (deliver'=true) & (run'=true) & (badObserve'=false); + [] lastSeen=13 & badObserve & observe13 (observe13'=observe13+1) & (deliver'=true) & (run'=true) & (badObserve'=false); + [] lastSeen=14 & badObserve & observe14 (observe14'=observe14+1) & (deliver'=true) & (run'=true) & (badObserve'=false); + [] lastSeen=15 & badObserve & observe15 (observe15'=observe15+1) & (deliver'=true) & (run'=true) & (badObserve'=false); + [] lastSeen=16 & badObserve & observe16 (observe16'=observe16+1) & (deliver'=true) & (run'=true) & (badObserve'=false); + [] lastSeen=17 & badObserve & observe17 (observe17'=observe17+1) & (deliver'=true) & (run'=true) & (badObserve'=false); + [] lastSeen=18 & badObserve & observe18 (observe18'=observe18+1) & (deliver'=true) & (run'=true) & (badObserve'=false); + [] lastSeen=19 & badObserve & observe19 (observe19'=observe19+1) & (deliver'=true) & (run'=true) & (badObserve'=false); + + // RECIPIENT + // Delivery to destination + [] deliver & run -> (done'=true) & (deliver'=false) & (run'=false) & (good'=false) & (bad'=false); + // Start a new instance + [] done -> (new'=true) & (done'=false) & (run'=false) & (lastSeen'=MaxGood); + +endmodule