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zeekayandHanzo Dev
1c7f329fbd
M-Chain is the MPC/threshold-custody VM that replaces off-chain signer clusters for bridge custody. This makes it one. vmID — the one-way door. factory.go declared a private `thresholdvm` literal that matched nothing else in the stack, and node/Dockerfile installed the plugin under that name's CB58 while genesis declares constants.MPCVMID. The two never met, so M-Chain could not have started. VMID is now the shared constant, and TestVMID_IsCanonicalAndStable pins the CB58 (qCURact1n41Fco...) with the list of every declaration that must move together if it ever changes before launch. k vs t. types.Ceremony carried Threshold/Total as bare uint16s: Validate read Threshold as the signer count (enforcing threshold*2 > total) while the VM read it as the polynomial degree and passed it straight to cmp.Keygen. The same field meant K in one file and t in another, and the two differ by one — the same silent off-by-one that produces a 4-of-5 wallet from a config saying 3-of-5. Both now carry a quorum.Policy, and t is only ever obtained by calling Degree(). The majority floor survives as types.HasUniqueQuorum, defined once and enforced on every key record. State. The VM kept its custody keys in a map persisted only on a clean Shutdown, with the key share excluded from the wire entirely, and reset lastAccepted to a recomputed genesis block on every Initialize — so a restart discarded the chain and came back unable to sign. State is now persisted at the moment each fact becomes true, split into a replicated c/ keyspace (key registry, ceremony log, blocks, height index, root) and a node-private n/ keyspace (this validator's shares), and Initialize resumes the accepted tip. Blocks verify. A block carries its post-state root and every operation's artifact. Verify re-checks a signature against the group key already in the registry — a proposer cannot fabricate one without forging ECDSA — and recomputes the root, so two validators that would diverge cannot both accept. Keygen operations carry a proof of possession by the new group key over its own registration; a participant additionally cross-checks the declared degree against its own share, so one honest participant rejects a mis-declared key. Ceremonies are leaderless. The id is derived from the task (key, digest, sorted signers), so every validator converges on the same ceremony with no announce round and no coordinator, and the committee is the chain's own validator set rather than an operator roster. Address derivation was SHA-256 where every EVM chain uses Keccak-256, so the published custody address did not belong to the group key. Funds sent there would have been unspendable. Deletes the duplicate signing paths and the in-memory session machinery: one way to generate a key, one way to sign. Co-authored-by: Hanzo Dev <[email protected]>