Use @noble/curves for Node signing (#565)

This package is newer than elliptic, has fewer dependencies, is better typed, and appears to be faster. Signed-off-by: Mark S. Lewis <Mark.S.Lewis@outlook.com>
hyperledger · Feb 28, 2023 · c040e52 · c040e52
1 parent 6262dee
commit c040e52
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Showing 4 changed files with 15 additions and 43 deletions.
diff --git a/node/package.json b/node/package.json
@@ -32,8 +32,8 @@
     "dependencies": {
         "@grpc/grpc-js": "^1.8.7",
         "@hyperledger/fabric-protos": "~0.2.0",
+        "@noble/curves": "^0.7.3",
         "asn1.js": "^5.4.1",
-        "elliptic": "^6.5.4",
         "google-protobuf": "^3.21.2"
     },
     "optionalDependencies": {

diff --git a/node/src/identity/asn1.ts b/node/src/identity/asn1.ts
@@ -8,7 +8,6 @@
 // @ts-nocheck
 
 import { define } from 'asn1.js';
-import BN from 'bn.js';
 import { KeyObject } from 'crypto';
 
 const ECPrivateKey = define('ECPrivateKey', function() {
@@ -20,13 +19,6 @@ const ECPrivateKey = define('ECPrivateKey', function() {
     );
 });
 
-const ECSignature = define('ECSignature', function() {
-    return this.seq().obj(
-        this.key('r').int(),
-        this.key('s').int()
-    );
-});
-
 export function ecPrivateKeyAsRaw(privateKey: KeyObject): { privateKey: Buffer, curveObjectId: number[] } {
     const privateKeyPem = privateKey.export({ format: 'der', type: 'sec1' });
     const decodedDer = ECPrivateKey.decode(privateKeyPem, 'der');
@@ -35,7 +27,3 @@ export function ecPrivateKeyAsRaw(privateKey: KeyObject): { privateKey: Buffer,
         curveObjectId: decodedDer.parameters,
     };
 }
-
-export function ecRawSignatureAsDer(r: BN, s: BN): Buffer {
-    return ECSignature.encode({ r, s }, 'der');
-}
diff --git a/node/src/identity/hsmsigner.ts b/node/src/identity/hsmsigner.ts
@@ -4,10 +4,8 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-import BN from 'bn.js';
-import * as elliptic from 'elliptic';
+import { P256 } from '@noble/curves/p256';
 import * as pkcs11js from 'pkcs11js';
-import { ecRawSignatureAsDer } from './asn1';
 import { Signer } from './signer';
 
 export interface HSMSignerOptions {
@@ -82,7 +80,6 @@ export class HSMSignerFactoryImpl implements HSMSignerFactory {
     newSigner(hsmSignerOptions: Readonly<HSMSignerOptions>): HSMSigner {
         const options = sanitizeOptions(hsmSignerOptions);
 
-        const supportedKeySize = 256;
         const pkcs11 = this.#pkcs11;
         const slot = this.#findSlotForLabel(options.label);
         const session = pkcs11.C_OpenSession(slot, pkcs11js.CKF_SERIAL_SESSION);
@@ -97,26 +94,13 @@ export class HSMSignerFactoryImpl implements HSMSignerFactory {
             throw err;
         }
 
-        const definedCurves = elliptic.curves as unknown as Record<string, elliptic.curves.PresetCurve>;
-        const ecdsaCurve = definedCurves[`p${supportedKeySize}`];
-
-        // currently the only supported curve is p256 and it will always have an 'n' value
-        const curveBigNum = ecdsaCurve.n!; // eslint-disable-line @typescript-eslint/no-non-null-assertion
-        const halfOrder = curveBigNum.shrn(1);
+        const compactSignatureLength = P256.CURVE.nByteLength * 2;
 
         return {
             signer: (digest) => {
                 pkcs11.C_SignInit(session, { mechanism: pkcs11js.CKM_ECDSA }, privateKeyHandle);
-                const sig = pkcs11.C_Sign(session, Buffer.from(digest), Buffer.alloc(supportedKeySize));
-
-                const r = new BN(sig.slice(0, sig.length / 2).toString('hex'), 16);
-                let s = new BN(sig.slice(sig.length / 2).toString('hex'), 16);
-
-                if (s.cmp(halfOrder) === 1) {
-                    s = curveBigNum.sub(s);
-                }
-
-                const signature = new Uint8Array(ecRawSignatureAsDer(r, s));
+                const compactSignature = pkcs11.C_Sign(session, Buffer.from(digest), Buffer.alloc(compactSignatureLength));
+                const signature = P256.Signature.fromCompact(compactSignature).normalizeS().toDERRawBytes();
                 return Promise.resolve(signature);
             },
             close: () => pkcs11.C_CloseSession(session),

diff --git a/node/src/identity/signers.ts b/node/src/identity/signers.ts
@@ -4,15 +4,17 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
+import { CurveFn } from '@noble/curves/abstract/weierstrass';
+import { P256 } from '@noble/curves/p256';
+import { P384 } from '@noble/curves/p384';
 import { KeyObject } from 'crypto';
-import { ec as EC } from 'elliptic';
 import { ecPrivateKeyAsRaw } from './asn1';
 import { HSMSignerFactory, HSMSignerFactoryImpl as HSMSignerFactoryImplType } from './hsmsigner';
 import { Signer } from './signer';
 
-const namedCurves: Record<string, EC> = {
-    '1.2.840.10045.3.1.7': new EC('p256'),
-    '1.3.132.0.34': new EC('p384'),
+const namedCurves: Record<string, CurveFn> = {
+    '1.2.840.10045.3.1.7': P256,
+    '1.3.132.0.34': P384,
 };
 
 /**
@@ -38,18 +40,16 @@ export function newPrivateKeySigner(key: KeyObject): Signer {
 }
 
 function newECPrivateKeySigner(key: KeyObject): Signer {
-    const { privateKey: rawKey, curveObjectId } = ecPrivateKeyAsRaw(key);
+    const { privateKey, curveObjectId } = ecPrivateKeyAsRaw(key);
     const curve = getCurve(curveObjectId);
-    const keyPair = curve.keyFromPrivate(rawKey, 'hex');
 
     return (digest) => {
-        const signature = curve.sign(digest, keyPair, { canonical: true });
-        const signatureBytes = new Uint8Array(signature.toDER());
-        return Promise.resolve(signatureBytes);
+        const signature = curve.sign(digest, privateKey, { lowS: true }).toDERRawBytes();
+        return Promise.resolve(signature);
     };
 }
 
-function getCurve(objectIdBytes: number[]): EC {
+function getCurve(objectIdBytes: number[]): CurveFn {
     const objectId = objectIdBytes.join('.');
     const curve = namedCurves[objectId];
     if (!curve) {