feat: soft nonce implementation

.github/workflows/backward.yml

@@ -26,12 +26,12 @@ jobs:
     steps:
       - name: checkout tkey repo
         uses: actions/checkout@v3
-        with:
-          path: tkey
+        # with:
+        #   path: tkey
 
-      - name: switch path
-        run: |
-          cd ./tkey
+      # - name: switch path
+      #   run: |
+      #     cd ./tkey
 
       - name: Set up node
         uses: actions/setup-node@v3
@@ -54,7 +54,7 @@ jobs:
         run: |
           cd ./backward-compatibility-tests
           npm i
-          for filename in ../tkey/packages/* ; do
+          for filename in ../packages/* ; do
             echo "installing $filename" || continue
             # ... install packed packages
             packagename="`ls ${filename}| grep tkey`"
@@ -63,5 +63,4 @@ jobs:
 
       - name: Running comp tests
         run: |
-          cd ./backward-compatibility-tests
           npm test

karmaBaseConfig.js

@@ -24,9 +24,9 @@ const localBrowserConfig = (webpackConfig, karmaConfig, packageConfig) => {
     frameworks: ["mocha", "webpack"],
 
     webpack: {
-      module: webpackConfig[1].module,
-      resolve: webpackConfig[1].resolve,
-      plugins: webpackConfig[1].plugins,
+      module: webpackConfig[0].module,
+      resolve: webpackConfig[0].resolve,
+      plugins: webpackConfig[0].plugins,
     },
 
     plugins: ["karma-mocha-reporter", "karma-webkit-launcher", "karma-chrome-launcher", "karma-firefox-launcher", "karma-mocha", "karma-webpack"],

packages/common-types/src/baseTypes/aggregateTypes.ts

@@ -196,6 +196,7 @@ export interface ShareRequestArgs {
 
 export type TkeyStoreItemType = {
   id: string;
+  value?: string;
 };
 
 export type ISeedPhraseStore = TkeyStoreItemType & {

packages/common-types/src/utils.ts

@@ -104,3 +104,7 @@ export function generateID(): string {
   // after the decimal.
   return `${Math.random().toString(36).substr(2, 9)}`;
 }
+
+export function generateSalt() {
+  return generatePrivate().toString("hex").padStart(64, "0");
+}

packages/core/src/core.ts

@@ -11,6 +11,7 @@ import {
   FromJSONConstructor,
   GenerateNewShareResult,
   generatePrivateExcludingIndexes,
+  generateSalt,
   getPubKeyECC,
   getPubKeyPoint,
   hexPoint,
@@ -52,6 +53,7 @@ import {
   toPrivKeyECC,
 } from "@tkey-mpc/common-types";
 import { generatePrivate } from "@toruslabs/eccrypto";
+import { keccak256 } from "@toruslabs/torus.js";
 import BN from "bn.js";
 import stringify from "json-stable-stringify";
 
@@ -66,8 +68,8 @@ import {
   lagrangeInterpolation,
 } from "./lagrangeInterpolatePolynomial";
 import Metadata from "./metadata";
-
 // TODO: handle errors for get and set with retries
+export const TSS_MODULE = "tssModule";
 
 class ThresholdKey implements ITKey {
   modules: ModuleMap;
@@ -98,6 +100,8 @@ class ThresholdKey implements ITKey {
 
   _shareSerializationMiddleware: ShareSerializationMiddleware;
 
+  _accountSalt: string;
+
   storeDeviceShare: (deviceShareStore: ShareStore, customDeviceInfo?: StringifiedType) => Promise<void>;
 
   haveWriteMetadataLock: string;
@@ -300,6 +304,11 @@ class ThresholdKey implements ITKey {
         });
         if (useTSS) {
           const { factorEncs, factorPubs, tssPolyCommits } = await this._initializeNewTSSKey(this.tssTag, deviceTSSShare, factorPub, deviceTSSIndex);
+          const accountSalt = generateSalt();
+          this._setTKeyStoreItem(TSS_MODULE, {
+            id: "accountSalt",
+            value: accountSalt,
+          });
           this.metadata.addTSSData({ tssTag: this.tssTag, tssNonce: 0, tssPolyCommits, factorPubs, factorEncs });
         }
         return this.getKeyDetails();
@@ -385,7 +394,7 @@ class ThresholdKey implements ITKey {
    * getTSSShare accepts a factorKey and returns the TSS share based on the factor encrypted TSS shares in the metadata
    * @param factorKey - factor key
    */
-  async getTSSShare(factorKey: BN, opts?: { threshold: number }): Promise<{ tssIndex: number; tssShare: BN }> {
+  async getTSSShare(factorKey: BN, opts?: { threshold: number; accountIndex?: number }): Promise<{ tssIndex: number; tssShare: BN }> {
     if (!this.privKey) throw CoreError.default("tss share cannot be returned until you've reconstructed tkey");
     const factorPub = getPubKeyPoint(factorKey);
     const factorEncs = this.getFactorEncs(factorPub);
@@ -407,6 +416,7 @@ class ThresholdKey implements ITKey {
 
     const userDec = tssShareBNs[0];
 
+    const { threshold, accountIndex } = opts || {};
     if (type === "direct") {
       const tssSharePub = ecCurve.g.mul(userDec);
       const tssCommitA0 = ecCurve.keyFromPublic({ x: tssCommits[0].x.toString(16, 64), y: tssCommits[0].y.toString(16, 64) }).getPublic();
@@ -416,6 +426,11 @@ class ThresholdKey implements ITKey {
         _tssSharePub = _tssSharePub.add(tssCommitA1);
       }
       if (tssSharePub.getX().cmp(_tssSharePub.getX()) === 0 && tssSharePub.getY().cmp(_tssSharePub.getY()) === 0) {
+        if (accountIndex && accountIndex > 0) {
+          const nonce = await this.computeAccountNonce(accountIndex);
+          const derivedShare = userDec.add(nonce).umod(ecCurve.n);
+          return { tssIndex, tssShare: derivedShare };
+        }
         return { tssIndex, tssShare: userDec };
       }
       throw new Error("user decryption does not match tss commitments...");
@@ -425,8 +440,6 @@ class ThresholdKey implements ITKey {
     const serverDecs = tssShareBNs.slice(1); // 5 elems
     const serverIndexes = new Array(serverDecs.length).fill(null).map((_, i) => i + 1);
 
-    const { threshold } = opts || {};
-
     const combis = kCombinations(serverDecs.length, threshold || Math.ceil(serverDecs.length / 2));
     for (let i = 0; i < combis.length; i++) {
       const combi = combis[i];
@@ -446,6 +459,11 @@ class ThresholdKey implements ITKey {
         _tssSharePub = _tssSharePub.add(tssCommitA1);
       }
       if (tssSharePub.getX().cmp(_tssSharePub.getX()) === 0 && tssSharePub.getY().cmp(_tssSharePub.getY()) === 0) {
+        if (accountIndex && accountIndex > 0) {
+          const nonce = await this.computeAccountNonce(accountIndex);
+          const derivedShare = tssShare.add(nonce).umod(ecCurve.n);
+          return { tssIndex, tssShare: derivedShare };
+        }
         return { tssIndex, tssShare };
       }
     }
@@ -461,8 +479,17 @@ class ThresholdKey implements ITKey {
     return tssPolyCommits;
   }
 
-  getTSSPub(): Point {
-    return this.getTSSCommits()[0];
+  async getTSSPub(accountIndex?: number): Promise<Point> {
+    const tssCommits = this.getTSSCommits();
+    if (accountIndex && accountIndex > 0) {
+      const nonce = await this.computeAccountNonce(accountIndex);
+      // we need to add the pub key nonce to the tssPub
+      const noncePub = ecCurve.keyFromPrivate(nonce.toString("hex")).getPublic();
+      const pubKeyPoint = ecCurve.keyFromPublic({ x: tssCommits[0].x.toString("hex"), y: tssCommits[0].y.toString("hex") }).getPublic();
+      const dervicepubKeyPoint = pubKeyPoint.add(noncePub);
+      return new Point(dervicepubKeyPoint.getX().toString("hex"), dervicepubKeyPoint.getY().toString("hex"));
+    }
+    return tssCommits[0];
   }
 
   /**
@@ -876,13 +903,18 @@ class ThresholdKey implements ITKey {
           serverEncs: refreshResponse.serverFactorEncs,
         };
       }
+      const accountSalt = generateSalt();
       this.metadata.addTSSData({
         tssTag: this.tssTag,
         tssNonce: newTssNonce,
         tssPolyCommits: newTSSCommits,
         factorPubs,
         factorEncs,
       });
+      this._setTKeyStoreItem(TSS_MODULE, {
+        id: "accountSalt",
+        value: accountSalt,
+      });
       await this._syncShareMetadata();
     } catch (error) {
       this.tssTag = oldTag;
@@ -1968,6 +2000,16 @@ class ThresholdKey implements ITKey {
   private async initializeModules() {
     return Promise.all(Object.keys(this.modules).map((x) => this.modules[x].initialize()));
   }
+
+  private async computeAccountNonce(index: number) {
+    // generation should occur during tkey.init, fails if accountSalt is absent
+    this._accountSalt = this._accountSalt || (await this.getTKeyStoreItem(TSS_MODULE, "accountSalt")).value;
+    if (!this._accountSalt) {
+      throw CoreError.accountSaltUndefined();
+    }
+    const accountHash = keccak256(Buffer.from(`${index}${this._accountSalt}`)).slice(2);
+    return index && index > 0 ? new BN(accountHash, "hex").umod(ecCurve.curve.n) : new BN(0);
+  }
 }
 
 export default ThresholdKey;

packages/core/src/errors.ts

@@ -32,6 +32,7 @@ class CoreError extends TkeyError {
     1103: "setMetadata errored",
     1104: "previouslyFetchedCloudMetadata provided in initialization is outdated",
     1105: "previouslyFetchedCloudMetadata.nonce should never be higher than the latestShareDetails, please contact support",
+    1106: "Account Salt is absent, required for nonce generation",
     // tkeystore
     1201: "Invalid tkeyStore",
     1202: "Encryption failed",
@@ -90,6 +91,10 @@ class CoreError extends TkeyError {
     return CoreError.fromCode(1103, extraMessage);
   }
 
+  public static accountSaltUndefined(extraMessage = ""): ITkeyError {
+    return CoreError.fromCode(1106, extraMessage);
+  }
+
   // TkeyData
   public static tkeyStoreInvalid(extraMessage = ""): ITkeyError {
     return CoreError.fromCode(1201, extraMessage);

packages/core/src/metadata.ts

@@ -186,6 +186,7 @@ class Metadata implements IMetadata {
     tssNonce?: number;
     tssPolyCommits?: Point[];
     factorPubs?: Point[];
+    accountIndex?: number;
     factorEncs?: {
       [factorPubID: string]: FactorEnc;
     };

packages/default/test/helpers.js

@@ -47,8 +47,6 @@ export function getServiceProvider(params) {
         // this url has no effect as postbox key is passed
         // passing it just to satisfy direct auth checks.
         baseUrl: "http://localhost:3000",
-        web3AuthClientId: "test",
-        network: "mainnet",
       },
     });
   }
@@ -180,7 +178,6 @@ export async function assignTssDkgKeys(opts) {
   for (let j = 0; j < maxTSSNonceToSimulate; j++) {
     const token = generateIdToken(verifierId);
     const extendedVerifierId = `${verifierId}\u0015${tssTag}\u0016${j}`;
-    console.log("extendedVerifierId", extendedVerifierId);
 
     const { serverEndpoints: sssEndpoints } = await serviceProvider.getSSSNodeDetails();
     const retrieveSharesResponse = await serviceProvider.customAuthInstance.torus.retrieveShares(