/opt/canhelp/node_modules/@noble/hashes/src
Edit: /opt/canhelp/node_modules/@noble/hashes/src/hmac.ts (3135B)
/**
* HMAC: RFC2104 message authentication code.
* @module
*/
import { abytes, aexists, ahash, clean, type CHash, type Hash } from './utils.ts';
/** Internal class for HMAC. */
export class _HMAC
> implements Hash<_HMAC> {
oHash: T;
iHash: T;
blockLen: number;
outputLen: number;
private finished = false;
private destroyed = false;
constructor(hash: CHash, key: Uint8Array) {
ahash(hash);
abytes(key, undefined, 'key');
this.iHash = hash.create() as T;
if (typeof this.iHash.update !== 'function')
throw new Error('Expected instance of class which extends utils.Hash');
this.blockLen = this.iHash.blockLen;
this.outputLen = this.iHash.outputLen;
const blockLen = this.blockLen;
const pad = new Uint8Array(blockLen);
// blockLen can be bigger than outputLen
pad.set(key.length > blockLen ? hash.create().update(key).digest() : key);
for (let i = 0; i < pad.length; i++) pad[i] ^= 0x36;
this.iHash.update(pad);
// By doing update (processing of first block) of outer hash here we can re-use it between multiple calls via clone
this.oHash = hash.create() as T;
// Undo internal XOR && apply outer XOR
for (let i = 0; i < pad.length; i++) pad[i] ^= 0x36 ^ 0x5c;
this.oHash.update(pad);
clean(pad);
}
update(buf: Uint8Array): this {
aexists(this);
this.iHash.update(buf);
return this;
}
digestInto(out: Uint8Array): void {
aexists(this);
abytes(out, this.outputLen, 'output');
this.finished = true;
this.iHash.digestInto(out);
this.oHash.update(out);
this.oHash.digestInto(out);
this.destroy();
}
digest(): Uint8Array {
const out = new Uint8Array(this.oHash.outputLen);
this.digestInto(out);
return out;
}
_cloneInto(to?: _HMAC): _HMAC {
// Create new instance without calling constructor since key already in state and we don't know it.
to ||= Object.create(Object.getPrototypeOf(this), {});
const { oHash, iHash, finished, destroyed, blockLen, outputLen } = this;
to = to as this;
to.finished = finished;
to.destroyed = destroyed;
to.blockLen = blockLen;
to.outputLen = outputLen;
to.oHash = oHash._cloneInto(to.oHash);
to.iHash = iHash._cloneInto(to.iHash);
return to;
}
clone(): _HMAC {
return this._cloneInto();
}
destroy(): void {
this.destroyed = true;
this.oHash.destroy();
this.iHash.destroy();
}
}
/**
* HMAC: RFC2104 message authentication code.
* @param hash - function that would be used e.g. sha256
* @param key - message key
* @param message - message data
* @example
* import { hmac } from '@noble/hashes/hmac';
* import { sha256 } from '@noble/hashes/sha2';
* const mac1 = hmac(sha256, 'key', 'message');
*/
export const hmac: {
(hash: CHash, key: Uint8Array, message: Uint8Array): Uint8Array;
create(hash: CHash, key: Uint8Array): _HMAC;
} = (hash: CHash, key: Uint8Array, message: Uint8Array): Uint8Array =>
new _HMAC(hash, key).update(message).digest();
hmac.create = (hash: CHash, key: Uint8Array) => new _HMAC(hash, key);