tornado-packages/noble-curves
1
0
Fork 1
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

utils: make equalBytes constant-time

Browse Source
This commit is contained in:
Paul Miller 2023-12-10 22:04:01 +00:00
parent 4ffb68853d
commit 8e6c19de2b
No known key found for this signature in database
GPG Key ID: 697079DA6878B89B
1 changed files with 7 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
src/abstract/utils.ts
View File

@ -20,6 +20,7 @@ function isBytes(a: any): a is Uint8Array {
return a instanceof Uint8Array || a.constructor.name === 'Uint8Array';
}
// Array where index 0xf0 (240) is mapped to string 'f0'
const hexes = /* @__PURE__ */ Array.from({ length: 256 }, (_, i) =>
i.toString(16).padStart(2, '0')
);
@ -147,11 +148,12 @@ export function concatBytes(...arrays: Uint8Array[]): Uint8Array {
return res;
}
export function equalBytes(b1: Uint8Array, b2: Uint8Array) {
// We don't care about timing attacks here
if (b1.length !== b2.length) return false;
for (let i = 0; i < b1.length; i++) if (b1[i] !== b2[i]) return false;
return true;
// Compares 2 u8a-s in kinda constant time
export function equalBytes(a: Uint8Array, b: Uint8Array) {
if (a.length !== b.length) return false;
let diff = 0;
for (let i = 0; i < a.length; i++) diff |= a[i] ^ b[i];
return diff === 0;
}
// Global symbols in both browsers and Node.js since v11