code moved to utils packages added more secure comparisons in order t…

…o mitigate CWE-208

packages/hardware-ledger/src/LedgerKeyAgent.ts

@@ -15,7 +15,7 @@ import {
 } from '@cardano-sdk/key-management';
 import { HID } from 'node-hid';
 import { LedgerDevice, LedgerTransportType } from './types';
-import { areConstantTimeEqualEnums, areConstantTimeEqualStrings } from './utils';
+import { areNumbersEqual, areStringsEqual } from '@cardano-sdk/util';
 import { str_to_path } from '@cardano-foundation/ledgerjs-hw-app-cardano/dist/utils/address';
 import { toLedgerTx } from './transformers';
 import TransportNodeHid from '@ledgerhq/hw-transport-node-hid-noevents';
@@ -130,15 +130,15 @@ const containsOnlyScriptHashCreds = (tx: Transaction): boolean => {
   // Ensure all withdrawals have the SCRIPT_HASH type
   const withdrawalsAllScriptHash = tx.withdrawals
     ? tx.withdrawals.every((withdrawal) =>
-        areConstantTimeEqualEnums(withdrawal.stakeCredential.type, StakeCredentialParamsType.SCRIPT_HASH)
+        areNumbersEqual(withdrawal.stakeCredential.type, StakeCredentialParamsType.SCRIPT_HASH)
       )
     : true;
 
   // Ensure all certificates, if present, only contain SCRIPT_HASH type credentials
   const certificatesAllScriptHash = tx.certificates
     ? tx.certificates.every((cert) => {
         const certParams = cert.params as unknown as StakeCredentialCertificateParams;
-        return areConstantTimeEqualEnums(certParams.stakeCredential.type, StakeCredentialParamsType.SCRIPT_HASH);
+        return areNumbersEqual(certParams.stakeCredential.type, StakeCredentialParamsType.SCRIPT_HASH);
       })
     : true;
 
@@ -553,7 +553,7 @@ export class LedgerKeyAgent extends KeyAgentBase {
         tx: ledgerTxData
       });
 
-      if (!areConstantTimeEqualStrings(result.txHashHex, hash)) {
+      if (!areStringsEqual(result.txHashHex, hash)) {
         throw new errors.HwMappingError('Ledger computed a different transaction id');
       }
 

packages/hardware-ledger/src/transformers/certificates.ts

@@ -1,9 +1,7 @@
-import * as Crypto from '@cardano-sdk/crypto';
 import * as Ledger from '@cardano-foundation/ledgerjs-hw-app-cardano';
 import { Cardano } from '@cardano-sdk/core';
-import { InvalidArgumentError, Transform } from '@cardano-sdk/util';
+import { InvalidArgumentError, Transform, areStringsEqual } from '@cardano-sdk/util';
 import { LedgerTxTransformerContext } from '../types';
-import { areConstantTimeEqualStrings } from '../utils';
 import { util } from '@cardano-sdk/key-management';
 
 type StakeKeyCertificateType = Ledger.CertificateType.STAKE_REGISTRATION | Ledger.CertificateType.STAKE_DEREGISTRATION;
@@ -21,7 +19,7 @@ const getStakeAddressCertificate = (
   type: StakeKeyCertificateType
 ): StakeKeyCertificate => {
   const knownAddress = context?.knownAddresses.find((address) =>
-    areConstantTimeEqualStrings(
+    areStringsEqual(
       Cardano.RewardAccount.toHash(address.rewardAccount) as unknown as string,
       certificate.stakeCredential.hash as unknown as string
     )
@@ -72,7 +70,7 @@ export const stakeDelegationCertificate: Transform<
 > = (certificate, context): Ledger.Certificate => {
   const poolIdKeyHash = Cardano.PoolId.toKeyHash(certificate.poolId);
   const knownAddress = context?.knownAddresses.find((address) =>
-    areConstantTimeEqualStrings(
+    areStringsEqual(
       Cardano.RewardAccount.toHash(address.rewardAccount) as unknown as string,
       certificate.stakeCredential.hash as unknown as string
     )
@@ -233,7 +231,7 @@ const poolRetirementCertificate: Transform<
   const poolIdKeyHash = Cardano.PoolId.toKeyHash(certificate.poolId);
 
   const knownAddress = context?.knownAddresses.find((address) =>
-    areConstantTimeEqualStrings(
+    areStringsEqual(
       Cardano.RewardAccount.toHash(address.rewardAccount) as unknown as string,
       poolIdKeyHash as unknown as string
     )

packages/hardware-ledger/src/transformers/requiredSigners.ts

@@ -2,7 +2,7 @@ import * as Crypto from '@cardano-sdk/crypto';
 import * as Ledger from '@cardano-foundation/ledgerjs-hw-app-cardano';
 import { Cardano } from '@cardano-sdk/core';
 import { LedgerTxTransformerContext } from '../types';
-import { Transform } from '@cardano-sdk/util';
+import { Transform, areStringsEqual } from '@cardano-sdk/util';
 import { util } from '@cardano-sdk/key-management';
 
 export const toRequiredSigner: Transform<
@@ -12,12 +12,12 @@ export const toRequiredSigner: Transform<
 > = (keyHash, context) => {
   const paymentCredKnownAddress = context?.knownAddresses.find((address) => {
     const paymentCredential = Cardano.Address.fromBech32(address.address)?.asBase()?.getPaymentCredential().hash;
-    return paymentCredential && paymentCredential.toString() === keyHash;
+    return !!paymentCredential && areStringsEqual(paymentCredential.toString(), keyHash);
   });
 
   const stakeCredKnownAddress = context?.knownAddresses.find((address) => {
     const stakeCredential = Cardano.RewardAccount.toHash(address.rewardAccount);
-    return stakeCredential && stakeCredential.toString() === keyHash;
+    return !!stakeCredential && areStringsEqual(stakeCredential.toString(), keyHash);
   });
 
   const paymentKeyPath = paymentCredKnownAddress

packages/hardware-ledger/src/transformers/withdrawals.ts

@@ -1,7 +1,7 @@
 import * as Ledger from '@cardano-foundation/ledgerjs-hw-app-cardano';
 import { Cardano } from '@cardano-sdk/core';
 import { CardanoKeyConst, GroupedAddress, util } from '@cardano-sdk/key-management';
-import { InvalidArgumentError, Transform } from '@cardano-sdk/util';
+import { InvalidArgumentError, Transform, areNumbersEqual } from '@cardano-sdk/util';
 import { LedgerTxTransformerContext } from '../types';
 
 const resolveKeyPath = (
@@ -38,7 +38,7 @@ export const toWithdrawal: Transform<Cardano.Withdrawal, Ledger.Withdrawal, Ledg
 
   let ledgerWithdrawal;
 
-  if (rewardAddress.getPaymentCredential().type === Cardano.CredentialType.KeyHash) {
+  if (areNumbersEqual(rewardAddress.getPaymentCredential().type, Cardano.CredentialType.KeyHash)) {
     const keyPath = resolveKeyPath(rewardAddress, context?.knownAddresses);
     ledgerWithdrawal = keyPath
       ? {

packages/hardware-trezor/src/TrezorKeyAgent.ts

@@ -15,6 +15,7 @@ import {
   errors,
   util
 } from '@cardano-sdk/key-management';
+import { areStringsEqual } from '@cardano-sdk/util';
 import { txToTrezor } from './transformers/tx';
 import _TrezorConnectWeb from '@trezor/connect-web';
 
@@ -238,7 +239,7 @@ export class TrezorKeyAgent extends KeyAgentBase {
 
       const signedData = result.payload;
 
-      if (signedData.hash !== hash) {
+      if (!areStringsEqual(signedData.hash, hash)) {
         throw new errors.HwMappingError('Trezor computed a different transaction id');
       }
 

packages/hardware-trezor/src/transformers/certificates.ts

@@ -3,7 +3,7 @@ import * as Trezor from '@trezor/connect';
 import { BIP32Path } from '@cardano-sdk/crypto';
 import { Cardano } from '@cardano-sdk/core';
 import { GroupedAddress, util } from '@cardano-sdk/key-management';
-import { InvalidArgumentError, Transform } from '@cardano-sdk/util';
+import { InvalidArgumentError, Transform, areNumbersEqual, areStringsEqual } from '@cardano-sdk/util';
 import { TrezorTxTransformerContext } from '../types';
 
 type CertCredentialsType = {
@@ -16,12 +16,12 @@ const getCertCredentials = (
   stakeKeyHash: Crypto.Ed25519KeyHashHex,
   knownAddresses: GroupedAddress[] | undefined
 ): CertCredentialsType => {
-  const knownAddress = knownAddresses?.find(
-    (address) => Cardano.RewardAccount.toHash(address.rewardAccount) === stakeKeyHash
+  const knownAddress = knownAddresses?.find((address) =>
+    areStringsEqual(Cardano.RewardAccount.toHash(address.rewardAccount), stakeKeyHash)
   );
   const rewardAddress = knownAddress ? Cardano.Address.fromBech32(knownAddress.rewardAccount)?.asReward() : null;
 
-  if (rewardAddress?.getPaymentCredential().type === Cardano.CredentialType.KeyHash) {
+  if (!!rewardAddress && areNumbersEqual(rewardAddress?.getPaymentCredential().type, Cardano.CredentialType.KeyHash)) {
     const path = util.stakeKeyPathFromGroupedAddress(knownAddress);
     return path ? { path } : { keyHash: stakeKeyHash };
   }

packages/hardware-trezor/src/transformers/requiredSigners.ts

@@ -1,7 +1,7 @@
 import * as Crypto from '@cardano-sdk/crypto';
 import * as Trezor from '@trezor/connect';
 import { Cardano } from '@cardano-sdk/core';
-import { Transform } from '@cardano-sdk/util';
+import { Transform, areStringsEqual } from '@cardano-sdk/util';
 import { TrezorTxTransformerContext } from '../types';
 import { util } from '@cardano-sdk/key-management';
 
@@ -12,12 +12,12 @@ export const toRequiredSigner: Transform<
 > = (keyHash, context) => {
   const paymentCredKnownAddress = context?.knownAddresses.find((address) => {
     const paymentCredential = Cardano.Address.fromBech32(address.address)?.asBase()?.getPaymentCredential().hash;
-    return paymentCredential && paymentCredential.toString() === keyHash;
+    return !!paymentCredential && areStringsEqual(paymentCredential.toString(), keyHash);
   });
 
   const stakeCredKnownAddress = context?.knownAddresses.find((address) => {
     const stakeCredential = Cardano.RewardAccount.toHash(address.rewardAccount);
-    return stakeCredential && stakeCredential.toString() === keyHash;
+    return !!stakeCredential && areStringsEqual(stakeCredential.toString(), keyHash);
   });
 
   const paymentKeyPath = paymentCredKnownAddress

packages/util/src/equals.ts

@@ -6,3 +6,50 @@ export const strictEquals = <T>(a: T, b: T) => a === b;
 
 export const sameArrayItems = <T>(arrayA: T[], arrayB: T[], itemEquals: (a: T, b: T) => boolean) =>
   arrayA.length === arrayB.length && arrayA.every((a) => arrayB.some((b) => itemEquals(a, b)));
+
+/**
+ * Performs a constant-time comparison of two number values to mitigate timing attacks (CWE-208).
+ *
+ * This function prevents timing attacks by ensuring that the time it takes to compare two number values
+ * is consistent, regardless of the values being compared.
+ *
+ * @param {number} a - The first number value to compare.
+ * @param {number} b - The second number value to compare.
+ * @returns {boolean} - Returns true if both number values are identical, otherwise returns false.
+ */
+export const areNumbersEqual = (a: number, b: number): boolean => (a ^ b) === 0; // This performs a constant-time comparison for number values
+
+/**
+ * Performs a constant-time comparison of two strings to mitigate timing attacks (CWE-208).
+ *
+ * This function is designed to prevent timing attacks by ensuring that the time it takes to compare two strings
+ * does not depend on the contents of the strings themselves. It achieves this by comparing all characters
+ * up to the length of the longer string, treating out-of-bounds characters as zeros, and using bitwise operations
+ * to maintain constant time execution.
+ *
+ * @param {string} a - The first string to compare.
+ * @param {string} b - The second string to compare.
+ * @returns {boolean} - Returns true if the strings are identical, false otherwise.
+ */
+export const areStringsEqual = (a: string, b: string): boolean => {
+  if (a.length !== b.length) return false;
+
+  // Calculate the maximum length of the two strings. This value will be used to loop through each character.
+  const maxLength = Math.max(a.length, b.length);
+
+  // It loops through the maximum length of the two strings, ensuring that the iteration count doesn't leak information about the length difference.
+  const results: (0 | 1)[] = Array.from({ length: maxLength }, (_, i) => {
+    const charCodeA = i < a.length ? a.charCodeAt(i) : 0;
+    const charCodeB = i < b.length ? b.charCodeAt(i) : 0;
+    return charCodeA === charCodeB ? 1 : 0; // Return 1 if the characters are equal, otherwise return 0.
+  });
+
+  // Reduce the results array to a single value, using bitwise AND, explicitly casting the result as binary 0 | 1.
+  // We do not use booleans here (true/false) instead 0 and 1 because bitwise operations in JavaScript operate on 32-bit integers.
+  const areAllCharactersEqual = results.reduce(
+    (accumulator: 0 | 1, currentValue: 0 | 1) => (accumulator & currentValue) as 0 | 1, // Cast to 0 | 1 to satisfy TypeScript's strict type checking.
+    1 as 0 | 1
+  );
+
+  return areAllCharactersEqual === 1; // Return `true` if all characters matched, otherwise `false`.
+};