Luke The Dev
44 lines
1.2 KiB
TypeScript
44 lines
1.2 KiB
TypeScript
type CryptoLike = {
|
|
randomUUID?: (() => string) | undefined;
|
|
getRandomValues?: ((array: Uint8Array) => Uint8Array) | undefined;
|
|
};
|
|
|
|
function uuidFromBytes(bytes: Uint8Array): string {
|
|
bytes[6] = (bytes[6] & 0x0f) | 0x40;
|
|
bytes[8] = (bytes[8] & 0x3f) | 0x80;
|
|
|
|
let hex = "";
|
|
for (let i = 0; i < bytes.length; i++) {
|
|
hex += bytes[i]!.toString(16).padStart(2, "0");
|
|
}
|
|
|
|
return `${hex.slice(0, 8)}-${hex.slice(8, 12)}-${hex.slice(12, 16)}-${hex.slice(
|
|
16,
|
|
20
|
|
)}-${hex.slice(20)}`;
|
|
}
|
|
|
|
function weakRandomBytes(): Uint8Array {
|
|
const bytes = new Uint8Array(16);
|
|
const now = Date.now();
|
|
for (let i = 0; i < bytes.length; i++) bytes[i] = Math.floor(Math.random() * 256);
|
|
bytes[0] ^= now & 0xff;
|
|
bytes[1] ^= (now >>> 8) & 0xff;
|
|
bytes[2] ^= (now >>> 16) & 0xff;
|
|
bytes[3] ^= (now >>> 24) & 0xff;
|
|
return bytes;
|
|
}
|
|
|
|
export function randomUUID(cryptoLike: CryptoLike | null | undefined = globalThis.crypto): string {
|
|
if (cryptoLike && typeof cryptoLike.randomUUID === "function") return cryptoLike.randomUUID();
|
|
|
|
if (cryptoLike && typeof cryptoLike.getRandomValues === "function") {
|
|
const bytes = new Uint8Array(16);
|
|
cryptoLike.getRandomValues(bytes);
|
|
return uuidFromBytes(bytes);
|
|
}
|
|
|
|
return uuidFromBytes(weakRandomBytes());
|
|
}
|
|
|