------------------------- MODULE counterexample ------------------------- EXTENDS MC10_3_faulty (* Initial state *) State1 == TRUE (* Transition 0 to State2 *) State2 == /\ Faulty = { "n10", "n2" } /\ blockchain = 1 :> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1] @@ 2 :> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n8", "n9" }, VS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, height |-> 2, lastCommit |-> { "n1", "n10", "n2", "n3", "n4", "n6", "n7", "n9" }, time |-> 2] @@ 3 :> [NextVS |-> { "n10", "n2", "n3", "n4", "n5", "n8", "n9" }, VS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n8", "n9" }, height |-> 3, lastCommit |-> { "n1", "n10", "n5", "n6", "n7", "n8" }, time |-> 3] @@ 4 :> [NextVS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, VS |-> { "n10", "n2", "n3", "n4", "n5", "n8", "n9" }, height |-> 4, lastCommit |-> { "n1", "n10", "n5", "n6", "n8", "n9" }, time |-> 4] /\ fetchedLightBlocks = 1 :> [Commits |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1]] /\ history = 0 :> [current |-> [Commits |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1]], now |-> 1400, verdict |-> "SUCCESS", verified |-> [Commits |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1]]] /\ latestVerified = [Commits |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1]] /\ lightBlockStatus = 1 :> "StateVerified" /\ nextHeight = 3 /\ now = 1400 /\ nprobes = 0 /\ prevCurrent = [Commits |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1]] /\ prevNow = 1400 /\ prevVerdict = "SUCCESS" /\ prevVerified = [Commits |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1]] /\ state = "working" (* Transition 1 to State3 *) State3 == /\ Faulty = { "n10", "n2" } /\ blockchain = 1 :> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1] @@ 2 :> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n8", "n9" }, VS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, height |-> 2, lastCommit |-> { "n1", "n10", "n2", "n3", "n4", "n6", "n7", "n9" }, time |-> 2] @@ 3 :> [NextVS |-> { "n10", "n2", "n3", "n4", "n5", "n8", "n9" }, VS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n8", "n9" }, height |-> 3, lastCommit |-> { "n1", "n10", "n5", "n6", "n7", "n8" }, time |-> 3] @@ 4 :> [NextVS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, VS |-> { "n10", "n2", "n3", "n4", "n5", "n8", "n9" }, height |-> 4, lastCommit |-> { "n1", "n10", "n5", "n6", "n8", "n9" }, time |-> 4] /\ fetchedLightBlocks = 1 :> [Commits |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1]] @@ 3 :> [Commits |-> {"n10"}, header |-> [NextVS |-> { "n4", "n7", "n9" }, VS |-> {"n10"}, height |-> 3, lastCommit |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n9" }, time |-> 2]] /\ history = 0 :> [current |-> [Commits |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1]], now |-> 1400, verdict |-> "SUCCESS", verified |-> [Commits |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1]]] @@ 1 :> [current |-> [Commits |-> {"n10"}, header |-> [NextVS |-> { "n4", "n7", "n9" }, VS |-> {"n10"}, height |-> 3, lastCommit |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n9" }, time |-> 2]], now |-> 1400, verdict |-> "NOT_ENOUGH_TRUST", verified |-> [Commits |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1]]] /\ latestVerified = [Commits |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1]] /\ lightBlockStatus = 1 :> "StateVerified" @@ 3 :> "StateUnverified" /\ nextHeight = 2 /\ now = 1400 /\ nprobes = 1 /\ prevCurrent = [Commits |-> {"n10"}, header |-> [NextVS |-> { "n4", "n7", "n9" }, VS |-> {"n10"}, height |-> 3, lastCommit |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n9" }, time |-> 2]] /\ prevNow = 1400 /\ prevVerdict = "NOT_ENOUGH_TRUST" /\ prevVerified = [Commits |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1]] /\ state = "working" (* Transition 3 to State4 *) State4 == /\ Faulty = { "n10", "n2" } /\ blockchain = 1 :> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1] @@ 2 :> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n8", "n9" }, VS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, height |-> 2, lastCommit |-> { "n1", "n10", "n2", "n3", "n4", "n6", "n7", "n9" }, time |-> 2] @@ 3 :> [NextVS |-> { "n10", "n2", "n3", "n4", "n5", "n8", "n9" }, VS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n8", "n9" }, height |-> 3, lastCommit |-> { "n1", "n10", "n5", "n6", "n7", "n8" }, time |-> 3] @@ 4 :> [NextVS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, VS |-> { "n10", "n2", "n3", "n4", "n5", "n8", "n9" }, height |-> 4, lastCommit |-> { "n1", "n10", "n5", "n6", "n8", "n9" }, time |-> 4] /\ fetchedLightBlocks = 1 :> [Commits |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1]] @@ 2 :> [Commits |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n8", "n9" }, VS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, height |-> 2, lastCommit |-> { "n1", "n10", "n2", "n3", "n4", "n6", "n7", "n9" }, time |-> 2]] @@ 3 :> [Commits |-> {"n10"}, header |-> [NextVS |-> { "n4", "n7", "n9" }, VS |-> {"n10"}, height |-> 3, lastCommit |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n9" }, time |-> 2]] /\ history = 0 :> [current |-> [Commits |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1]], now |-> 1400, verdict |-> "SUCCESS", verified |-> [Commits |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1]]] @@ 1 :> [current |-> [Commits |-> {"n10"}, header |-> [NextVS |-> { "n4", "n7", "n9" }, VS |-> {"n10"}, height |-> 3, lastCommit |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n9" }, time |-> 2]], now |-> 1400, verdict |-> "NOT_ENOUGH_TRUST", verified |-> [Commits |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1]]] @@ 2 :> [current |-> [Commits |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n8", "n9" }, VS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, height |-> 2, lastCommit |-> { "n1", "n10", "n2", "n3", "n4", "n6", "n7", "n9" }, time |-> 2]], now |-> 1400, verdict |-> "SUCCESS", verified |-> [Commits |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1]]] /\ latestVerified = [Commits |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n8", "n9" }, VS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, height |-> 2, lastCommit |-> { "n1", "n10", "n2", "n3", "n4", "n6", "n7", "n9" }, time |-> 2]] /\ lightBlockStatus = 1 :> "StateVerified" @@ 2 :> "StateVerified" @@ 3 :> "StateUnverified" /\ nextHeight = 3 /\ now = 1400 /\ nprobes = 2 /\ prevCurrent = [Commits |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n8", "n9" }, VS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, height |-> 2, lastCommit |-> { "n1", "n10", "n2", "n3", "n4", "n6", "n7", "n9" }, time |-> 2]] /\ prevNow = 1400 /\ prevVerdict = "SUCCESS" /\ prevVerified = [Commits |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, header |-> [NextVS |-> { "n1", "n10", "n2", "n3", "n5", "n6", "n7", "n8" }, VS |-> { "n1", "n10", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9" }, height |-> 1, lastCommit |-> {}, time |-> 1]] /\ state = "working" (* The following formula holds true in the last state and violates the invariant *) InvariantViolation == Cardinality((DOMAIN fetchedLightBlocks)) = 3 /\ BMC!Skolem((\E s$2 \in DOMAIN history: 3 * Cardinality(history[s$2]["current"]["Commits"]) >= 2 * Cardinality(history[s$2]["current"]["header"]["VS"]))) ================================================================================ \* Created by Apalache on Wed Nov 18 14:00:20 UTC 2020 \* https://github.com/informalsystems/apalache