Merge pull request #5555 from BitGo/BTC-1829.add-trdecay

feat(utxo-staking): use miniscript AST for descriptor creation

modules/abstract-utxo/package.json

@@ -48,7 +48,7 @@
     "@bitgo/unspents": "^0.47.17",
     "@bitgo/utxo-core": "^1.1.0",
     "@bitgo/utxo-lib": "^11.2.1",
-    "@bitgo/wasm-miniscript": "^2.0.0-beta.3",
+    "@bitgo/wasm-miniscript": "^2.0.0-beta.4",
     "@types/bluebird": "^3.5.25",
     "@types/lodash": "^4.14.121",
     "@types/superagent": "4.1.15",

modules/utxo-bin/package.json

@@ -30,7 +30,7 @@
     "@bitgo/statics": "^50.24.0",
     "@bitgo/unspents": "^0.47.17",
     "@bitgo/utxo-lib": "^11.2.1",
-    "@bitgo/wasm-miniscript": "^2.0.0-beta.3",
+    "@bitgo/wasm-miniscript": "^2.0.0-beta.4",
     "archy": "^1.0.0",
     "bech32": "^2.0.0",
     "bitcoinjs-lib": "npm:@bitgo-forks/[email protected]",

modules/utxo-core/package.json

@@ -53,7 +53,7 @@
   "dependencies": {
     "@bitgo/unspents": "^0.47.17",
     "@bitgo/utxo-lib": "^11.2.1",
-    "@bitgo/wasm-miniscript": "^2.0.0-beta.3",
+    "@bitgo/wasm-miniscript": "^2.0.0-beta.4",
     "bip174": "npm:@bitgo-forks/[email protected]"
   },
   "gitHead": "18e460ddf02de2dbf13c2aa243478188fb539f0c"

modules/utxo-core/src/testutil/descriptor/descriptors.ts

@@ -1,4 +1,6 @@
-import { Descriptor } from '@bitgo/wasm-miniscript';
+import assert from 'assert';
+
+import { Descriptor, ast } from '@bitgo/wasm-miniscript';
 import { BIP32Interface } from '@bitgo/utxo-lib';
 
 import { DescriptorMap, PsbtParams } from '../../descriptor';
@@ -47,36 +49,22 @@ export type DescriptorTemplate =
    */
   | 'ShWsh2Of3CltvDrop';
 
-function toXPub(k: BIP32Interface | string): string {
+function toXPub(k: BIP32Interface | string, path: string): string {
   if (typeof k === 'string') {
-    return k;
+    return k + '/' + path;
   }
-  return k.neutered().toBase58();
+  return k.neutered().toBase58() + '/' + path;
 }
 
-function multi(
-  prefix: 'multi' | 'multi_a',
-  m: number,
-  n: number,
-  keys: BIP32Interface[] | string[],
-  path: string
-): string {
+function multiArgs(m: number, n: number, keys: BIP32Interface[] | string[], path: string): [number, ...string[]] {
   if (n < m) {
     throw new Error(`Cannot create ${m} of ${n} multisig`);
   }
   if (keys.length < n) {
     throw new Error(`Not enough keys for ${m} of ${n} multisig: keys.length=${keys.length}`);
   }
   keys = keys.slice(0, n);
-  return prefix + `(${m},${keys.map((k) => `${toXPub(k)}/${path}`).join(',')})`;
-}
-
-function multiWsh(m: number, n: number, keys: BIP32Interface[] | string[], path: string): string {
-  return multi('multi', m, n, keys, path);
-}
-
-function multiTap(m: number, n: number, keys: BIP32Interface[] | string[], path: string): string {
-  return multi('multi_a', m, n, keys, path);
+  return [m, ...keys.map((k) => toXPub(k, path))];
 }
 
 export function getPsbtParams(t: DescriptorTemplate): Partial<PsbtParams> {
@@ -90,21 +78,34 @@ export function getPsbtParams(t: DescriptorTemplate): Partial<PsbtParams> {
   }
 }
 
-export function getDescriptorString(
+function getDescriptorNode(
   template: DescriptorTemplate,
   keys: KeyTriple | string[] = getDefaultXPubs(),
   path = '0/*'
-): string {
+): ast.DescriptorNode {
   switch (template) {
     case 'Wsh2Of3':
-      return `wsh(${multiWsh(2, 3, keys, path)})`;
+      return {
+        wsh: { multi: multiArgs(2, 3, keys, path) },
+      };
     case 'ShWsh2Of3CltvDrop':
       const { locktime } = getPsbtParams(template);
-      return `sh(wsh(and_v(r:after(${locktime}),${multiWsh(2, 3, keys, path)})))`;
+      assert(locktime);
+      return {
+        sh: {
+          wsh: {
+            and_v: [{ 'r:after': locktime }, { multi: multiArgs(2, 3, keys, path) }],
+          },
+        },
+      };
     case 'Wsh2Of2':
-      return `wsh(${multiWsh(2, 2, keys, path)})`;
+      return {
+        wsh: { multi: multiArgs(2, 2, keys, path) },
+      };
     case 'Tr2Of3-NoKeyPath':
-      return `tr(${getUnspendableKey()},${multiTap(2, 3, keys, path)})`;
+      return {
+        tr: [getUnspendableKey(), { multi_a: multiArgs(2, 3, keys, path) }],
+      };
   }
   throw new Error(`Unknown descriptor template: ${template}`);
 }
@@ -114,7 +115,7 @@ export function getDescriptor(
   keys: KeyTriple | string[] = getDefaultXPubs(),
   path = '0/*'
 ): Descriptor {
-  return Descriptor.fromString(getDescriptorString(template, keys, path), 'derivable');
+  return Descriptor.fromString(ast.formatNode(getDescriptorNode(template, keys, path)), 'derivable');
 }
 
 export function getDescriptorMap(

modules/utxo-staking/package.json

@@ -42,7 +42,7 @@
     "@bitgo/utxo-core": "^1.1.0",
     "@bitgo/unspents": "^0.47.17",
     "@bitgo/utxo-lib": "^11.2.1",
-    "@bitgo/wasm-miniscript": "^2.0.0-beta.3"
+    "@bitgo/wasm-miniscript": "^2.0.0-beta.4"
   },
   "devDependencies": {
     "bitcoinjs-lib": "^6.1.7",

modules/utxo-staking/src/babylon/descriptor.ts

@@ -1,25 +1,24 @@
 import { Descriptor, ast } from '@bitgo/wasm-miniscript';
-import { MiniscriptNode } from '@bitgo/wasm-miniscript/dist/node/js/ast';
 
 export function getUnspendableKey(): string {
   // https://github.com/babylonlabs-io/btc-staking-ts/blob/v0.4.0-rc.2/src/constants/internalPubkey.ts
   return '50929b74c1a04954b78b4b6035e97a5e078a5a0f28ec96d547bfee9ace803ac0';
 }
 
 // Helper functions for creating miniscript nodes
-function pk(b: Buffer): MiniscriptNode {
+function pk(b: Buffer): ast.MiniscriptNode {
   return { 'v:pk': b.toString('hex') };
 }
 
 function sortedKeys(keys: Buffer[]): Buffer[] {
   return keys.sort((a, b) => a.compare(b));
 }
 
-function multi_a(threshold: number, keys: Buffer[]): { multi_a: [number, ...string[]] } {
-  return { multi_a: [threshold, ...sortedKeys(keys).map((k) => k.toString('hex'))] };
+function multiArgs(threshold: number, keys: Buffer[]): [number, ...string[]] {
+  return [threshold, ...sortedKeys(keys).map((k) => k.toString('hex'))];
 }
 
-function taprootScriptOnlyFromAst(n: ast.MiniscriptNode): Descriptor {
+function taprootScriptOnlyFromAst(n: ast.TapTreeNode): Descriptor {
   return Descriptor.fromString(ast.formatNode({ tr: [getUnspendableKey(), n] }), 'definite');
 }
 
@@ -33,45 +32,41 @@ export class BabylonDescriptorBuilder {
     public unbondingTimeLock: number
   ) {}
 
-  getTimelockMiniscript(): MiniscriptNode {
+  getTimelockMiniscript(): ast.MiniscriptNode {
     return { and_v: [pk(this.stakerKey), { older: this.stakingTimeLock }] };
   }
 
-  getUnbondingMiniscript(): MiniscriptNode {
-    return { and_v: [pk(this.stakerKey), multi_a(this.covenantThreshold, this.covenantKeys)] };
+  getUnbondingMiniscript(): ast.MiniscriptNode {
+    return { and_v: [pk(this.stakerKey), { multi_a: multiArgs(this.covenantThreshold, this.covenantKeys) }] };
   }
 
-  getSlashingMiniscript(): MiniscriptNode {
+  getSlashingMiniscript(): ast.MiniscriptNode {
     return {
       and_v: [
         {
-          and_v: [pk(this.stakerKey), { 'v:multi_a': multi_a(1, this.finalityProviderKeys).multi_a }],
+          and_v: [pk(this.stakerKey), { 'v:multi_a': multiArgs(1, this.finalityProviderKeys) }],
         },
-        multi_a(this.covenantThreshold, this.covenantKeys),
+        { multi_a: multiArgs(this.covenantThreshold, this.covenantKeys) },
       ],
     };
   }
 
-  getUnbondingTimelockMiniscript(): MiniscriptNode {
+  getUnbondingTimelockMiniscript(): ast.MiniscriptNode {
     return { and_v: [pk(this.stakerKey), { older: this.unbondingTimeLock }] };
   }
 
   getStakingDescriptor(): Descriptor {
-    const a = ast.formatNode(this.getSlashingMiniscript());
-    const b = ast.formatNode(this.getUnbondingMiniscript());
-    const c = ast.formatNode(this.getTimelockMiniscript());
-    const desc = `tr(${getUnspendableKey()},{${a},{${b},${c}}})`;
-    return Descriptor.fromString(desc, 'definite');
+    return taprootScriptOnlyFromAst([
+      this.getSlashingMiniscript(),
+      [this.getUnbondingMiniscript(), this.getTimelockMiniscript()],
+    ]);
   }
 
   getSlashingDescriptor(): Descriptor {
     return taprootScriptOnlyFromAst(this.getUnbondingTimelockMiniscript());
   }
 
   getUnbondingDescriptor(): Descriptor {
-    const a = ast.formatNode(this.getSlashingMiniscript());
-    const b = ast.formatNode(this.getUnbondingTimelockMiniscript());
-    const desc = `tr(${getUnspendableKey()},{${a},${b}})`;
-    return Descriptor.fromString(desc, 'definite');
+    return taprootScriptOnlyFromAst([this.getSlashingMiniscript(), this.getUnbondingTimelockMiniscript()]);
   }
 }

modules/utxo-staking/src/coreDao/descriptor.ts

@@ -1,4 +1,5 @@
 import { BIP32Interface } from '@bitgo/utxo-lib';
+import { ast } from '@bitgo/wasm-miniscript';
 
 /**
  * Script type for a descriptor.
@@ -39,13 +40,13 @@ export function createMultiSigDescriptor(
     throw new Error(`locktime (${locktime}) must be greater than 0`);
   }
   const keys = orderedKeys.map((key) => asDescriptorKey(key, neutered));
-  const inner = `and_v(r:after(${locktime}),multi(${m},${keys.join(',')}))`;
+  const inner: ast.MiniscriptNode = { and_v: [{ 'r:after': locktime }, { multi: [m, ...keys] }] };
   switch (scriptType) {
     case 'sh':
-      return `sh(${inner})`;
+      return ast.formatNode({ sh: inner });
     case 'sh-wsh':
-      return `sh(wsh(${inner}))`;
+      return ast.formatNode({ sh: { wsh: inner } });
     case 'wsh':
-      return `wsh(${inner})`;
+      return ast.formatNode({ wsh: inner });
   }
 }

yarn.lock

@@ -886,10 +886,10 @@
     monocle-ts "^2.3.13"
     newtype-ts "^0.3.5"
 
-"@bitgo/wasm-miniscript@^2.0.0-beta.3":
-  version "2.0.0-beta.3"
-  resolved "https://registry.npmjs.org/@bitgo/wasm-miniscript/-/wasm-miniscript-2.0.0-beta.3.tgz#f52f9fa411f4f13527c960842f81729133aa6810"
-  integrity sha512-9JWfizfdpSExQ5qDkMlZAR0UbonKILPwDXM+iqiBKIRGwlYak071lX9sfGPWoRuo7g72gU//s7AiZc6kZqgetw==
+"@bitgo/wasm-miniscript@^2.0.0-beta.4":
+  version "2.0.0-beta.4"
+  resolved "https://registry.npmjs.org/@bitgo/wasm-miniscript/-/wasm-miniscript-2.0.0-beta.4.tgz#6897327a0e6007cfa02081a02cba8b442e318dc5"
+  integrity sha512-lZCSo3NY/vb1hagU3J7fIdv7GhCGYb/INCdAi6ogDXBzWDl3tloviCZ9DXCNPXc7lbj8mVr3GR8zAFkPTQ0xEw==
 
 "@brandonblack/musig@^0.0.1-alpha.0":
   version "0.0.1-alpha.1"