Silent payment basic scheme

package.json

@@ -57,7 +57,6 @@
     "blech32": "^1.0.1",
     "bs58check": "^2.0.0",
     "create-hash": "^1.2.0",
-    "ecpair": "^2.1.0",
     "slip77": "^0.2.0",
     "typeforce": "^1.11.3",
     "varuint-bitcoin": "^1.1.2"
@@ -78,6 +77,7 @@
     "bn.js": "^4.11.8",
     "bs58": "^4.0.0",
     "dhttp": "^3.0.0",
+    "ecpair": "^2.1.0",
     "hoodwink": "^2.0.0",
     "minimaldata": "^1.0.2",
     "mocha": "^10.1.0",
@@ -88,7 +88,7 @@
     "randombytes": "^2.1.0",
     "regtest-client": "0.2.0",
     "rimraf": "^2.6.3",
-    "tiny-secp256k1": "^2.2.1",
+    "tiny-secp256k1": "^2.2.3",
     "ts-node": "^10.9.1",
     "tslint": "^6.1.3",
     "typescript": "^4.4.4"

src/bip341.js

@@ -120,7 +120,7 @@ function taprootSignScriptStack(ecc) {
   return (internalPublicKey, leaf, treeRootHash, path) => {
     const { parity } = tweakPublicKey(internalPublicKey, treeRootHash, ecc);
     const parityBit = Buffer.of(
-      leaf.version || exports.LEAF_VERSION_TAPSCRIPT + parity,
+      (leaf.version || exports.LEAF_VERSION_TAPSCRIPT) + parity,
     );
     const control = Buffer.concat([
       parityBit,

src/index.d.ts

@@ -1,12 +1,12 @@
-import * as address from './address';
-import * as crypto from './crypto';
-import * as networks from './networks';
-import * as payments from './payments';
-import * as script from './script';
-import * as issuance from './issuance';
-import * as bip341 from './bip341';
-import * as confidential from './confidential';
-export { address, confidential, crypto, networks, payments, script, issuance, bip341, };
+export * as address from './address';
+export * as crypto from './crypto';
+export * as networks from './networks';
+export * as payments from './payments';
+export * as script from './script';
+export * as issuance from './issuance';
+export * as bip341 from './bip341';
+export * as confidential from './confidential';
+export * as silentpayment from './silentpayment';
 export { OPS as opcodes } from './ops';
 export { Input as TxInput, Output as TxOutput, Transaction, } from './transaction';
 export * from './asset';

src/index.js

@@ -53,31 +53,25 @@ var __exportStar =
 Object.defineProperty(exports, '__esModule', { value: true });
 exports.Transaction =
   exports.opcodes =
+  exports.silentpayment =
+  exports.confidential =
   exports.bip341 =
   exports.issuance =
   exports.script =
   exports.payments =
   exports.networks =
   exports.crypto =
-  exports.confidential =
   exports.address =
     void 0;
-const address = __importStar(require('./address'));
-exports.address = address;
-const crypto = __importStar(require('./crypto'));
-exports.crypto = crypto;
-const networks = __importStar(require('./networks'));
-exports.networks = networks;
-const payments = __importStar(require('./payments'));
-exports.payments = payments;
-const script = __importStar(require('./script'));
-exports.script = script;
-const issuance = __importStar(require('./issuance'));
-exports.issuance = issuance;
-const bip341 = __importStar(require('./bip341'));
-exports.bip341 = bip341;
-const confidential = __importStar(require('./confidential'));
-exports.confidential = confidential;
+exports.address = __importStar(require('./address'));
+exports.crypto = __importStar(require('./crypto'));
+exports.networks = __importStar(require('./networks'));
+exports.payments = __importStar(require('./payments'));
+exports.script = __importStar(require('./script'));
+exports.issuance = __importStar(require('./issuance'));
+exports.bip341 = __importStar(require('./bip341'));
+exports.confidential = __importStar(require('./confidential'));
+exports.silentpayment = __importStar(require('./silentpayment'));
 var ops_1 = require('./ops');
 Object.defineProperty(exports, 'opcodes', {
   enumerable: true,

src/silentpayment.d.ts

@@ -0,0 +1,53 @@
+/// <reference types="node" />
+import { bip341 } from '.';
+export declare type Target = {
+    silentPaymentAddress: string;
+    value: number;
+    asset: string;
+};
+export declare type Output = {
+    scriptPubKey: string;
+    value: number;
+    asset: string;
+};
+export interface TinySecp256k1Interface extends bip341.BIP341Secp256k1Interface {
+    privateMultiply: (key: Uint8Array, tweak: Uint8Array) => Uint8Array;
+    pointMultiply: (point: Uint8Array, tweak: Uint8Array) => Uint8Array | null;
+    pointAdd: (point1: Uint8Array, point2: Uint8Array) => Uint8Array | null;
+    pointFromScalar: (key: Uint8Array) => Uint8Array | null;
+    privateAdd: (key: Uint8Array, tweak: Uint8Array) => Uint8Array | null;
+    privateNegate: (key: Uint8Array) => Uint8Array;
+    ecdh: (pubkey: Uint8Array, privkey: Uint8Array) => Uint8Array;
+}
+export declare class SilentPaymentAddress {
+    readonly spendPublicKey: Buffer;
+    readonly scanPublicKey: Buffer;
+    constructor(spendPublicKey: Buffer, scanPublicKey: Buffer);
+    static decode(str: string): SilentPaymentAddress;
+    encode(): string;
+}
+export declare class SilentPayment {
+    private ecc;
+    constructor(ecc: TinySecp256k1Interface);
+    /**
+     * create the transaction outputs sending outpoints identified by *outpointHash* to the *targets*
+     * @param inputsOutpointsHash hash of the input outpoints sent to the targets
+     * @param sumInputsPrivKeys sum of input private keys
+     * @param targets silent payment addresses receiving value/asset pair
+     * @returns a list of "silent-payment" taproot outputs
+     */
+    pay(inputsOutpointsHash: Buffer, sumInputsPrivKeys: Buffer, targets: Target[]): Output[];
+    sumSecretKeys(outpointKeys: {
+        key: Buffer;
+        isTaproot?: boolean;
+    }[]): Buffer;
+    sumPublicKeys(keys: Buffer[]): Buffer;
+    makeSharedSecret(inputsOutpointsHash: Buffer, inputPubKey: Buffer, scanSecretKey: Buffer): Buffer;
+    makePublicKey(spendPubKey: Buffer, index: number, ecdhSharedSecret: Buffer): Buffer;
+    makeSecretKey(spendPrivKey: Buffer, index: number, ecdhSharedSecret: Buffer): Buffer;
+}
+export declare function ser32(i: number): Buffer;
+export declare function outpointsHash(parameters: {
+    txid: string;
+    vout: number;
+}[]): Buffer;