V2.1 (#21)

Working version Reviewed-on: #21
2026-11-01 22:07:51 +00:00
parent 1edf2e6200
commit 636f5b9c77
80 changed files with 4065 additions and 549 deletions
@@ -0,0 +1,66 @@
+import { CONSENSUS, type TestnetBlock } from '../../shared/testnet.ts';
+import { CHAIN_ID, GENESIS_TIME, MAX_TARGET, expectedTarget, medianTime, workFor } from '../testnet/consensus.ts';
+
+const SPACE = 1n << 256n;
+/** Analysis only. Calls the actual retarget/median helpers but DOES NOT construct valid blocks,
+ * perform PoW, invoke Ledger, or provide a production fake-PoW selector. */
+export type Scenario = 'steady' | 'rapid' | 'slow' | 'stall' | 'median-minimum' | 'future-edge';
+export type TracePoint = { height: number; wallTime: number; timestamp: number; target: string;
+  cumulativeWork: string; expectedHashes: number; nextTarget: string };
+export function expectedHashes(target: string): number {
+  if (!/^[a-f0-9]{64}$/.test(target)) throw new Error('Invalid target');
+  return Number(SPACE) / Number(BigInt(`0x${target}`) + 1n);
+}
+export function targetForHashrate(hashesPerSecond: number, seconds = CONSENSUS.targetSeconds): string {
+  if (!Number.isSafeInteger(hashesPerSecond) || hashesPerSecond < 1 || hashesPerSecond > 1_000_000_000_000 ||
+      !Number.isSafeInteger(seconds) || seconds < 1 || seconds > 86400) throw new Error('Hashrate/interval outside analysis bounds');
+  const denominator = BigInt(hashesPerSecond) * BigInt(seconds);
+  const target = SPACE / denominator - 1n;
+  const maximum = BigInt(`0x${MAX_TARGET}`);
+  return (target < 1n ? 1n : target > maximum ? maximum : target).toString(16).padStart(64,'0');
+}
+export function simulate(scenario: Scenario, count = 60): TracePoint[] {
+  if (!['steady','rapid','slow','stall','median-minimum','future-edge'].includes(scenario) ||
+      !Number.isSafeInteger(count) || count < 1 || count > 1000) throw new Error('Invalid bounded simulation');
+  const history: TestnetBlock[] = [], result: TracePoint[] = [];
+  let wallTime = GENESIS_TIME, cumulativeWork = 0n;
+  for (let i = 0; i < count; i++) {
+    const target = expectedTarget(history);
+    const spacing = scenario === 'rapid' ? 1 : scenario === 'slow' ? CONSENSUS.targetSeconds * 8
+      : scenario === 'stall' && i === 20 ? 7 * 86400 : CONSENSUS.targetSeconds;
+    wallTime += spacing;
+    const timestamp = scenario === 'median-minimum' ? medianTime(history) + 1
+      : scenario === 'future-edge' ? wallTime + CONSENSUS.maxFutureSeconds : wallTime;
+    if (timestamp <= medianTime(history) || timestamp > wallTime + CONSENSUS.maxFutureSeconds) throw new Error('Analysis generated an invalid timestamp');
+    // Only these fields are read by expectedTarget/medianTime. Never submit these records to a node.
+    history.push({ createdAt: timestamp, target } as TestnetBlock);
+    cumulativeWork += workFor(target);
+    result.push({ height:i+1,wallTime,timestamp,target,cumulativeWork:cumulativeWork.toString(),
+      expectedHashes:expectedHashes(target),nextTarget:expectedTarget(history) });
+  }
+  return result;
+}
+/** Idealized fixed-difficulty Poisson race: probability of ever catching up from a CURRENT
+ * known z-block deficit, q<p. NOT probability of double-spend after z confirmations. */
+export function idealCatchup(attackerShare: number, deficit: number): number {
+  if (!Number.isFinite(attackerShare) || attackerShare < 0 || attackerShare > 1 ||
+      !Number.isSafeInteger(deficit) || deficit < 0 || deficit > 1000) throw new Error('Invalid race assumptions');
+  if (deficit === 0 || attackerShare >= .5) return 1;
+  return (attackerShare / (1-attackerShare)) ** deficit;
+}
+export function calibrationReport() {
+  const scenarios = Object.fromEntries((['steady','rapid','slow','stall','median-minimum','future-edge'] as const)
+    .map(name=>[name,simulate(name)]));
+  const a=scenarios.steady.at(-1)!,b=scenarios.rapid.at(-1)!;
+  return { schema:'wikideck-consensus-analysis-v1',chainId:CHAIN_ID,consensusChanged:false,
+    scope:'Deterministic header-math scenarios only; no valid blocks, mining or launch.',
+    initialExpectedHashes:expectedHashes(MAX_TARGET),targetSeconds:CONSENSUS.targetSeconds,
+    assumptions:'Spacing is externally imposed, not stochastic mining at constant hashrate. Work comparisons do not imply an attacker can produce that work.',
+    scenarios,
+    partitionExample:{steadyHeight:a.height,rapidHeight:b.height,steadyWork:a.cumulativeWork,rapidWork:b.cumulativeWork,
+      winnerByStrictWork:BigInt(b.cumulativeWork)>BigInt(a.cumulativeWork)?'rapid':'steady',
+      warning:'Models fork-choice inputs, not peer synchronization, block validity or achievable hashpower.'},
+    knownDeficitCatchup:[.1,.25,.4,.49].map(share=>({attackerShare:share,probability:idealCatchup(share,10),currentDeficit:10})),
+    candidateTargets:[1,10,100,1000,10000].map(hps=>({assumedNetworkHashesPerSecond:hps,target:targetForHashrate(hps)})),
+    decision:'NO-GO: measurement, independent analysis, multi-host rehearsal and explicit operator approval still required.' };
+}