| 1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677 | import { hash as assertHash, bytes as assertBytes, exists as assertExists } from './_assert.js';import { Hash, toBytes } from './utils.js';// HMAC (RFC 2104)export class HMAC extends Hash {    constructor(hash, _key) {        super();        this.finished = false;        this.destroyed = false;        assertHash(hash);        const key = toBytes(_key);        this.iHash = hash.create();        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();        // Undo internal XOR && apply outer XOR        for (let i = 0; i < pad.length; i++)            pad[i] ^= 0x36 ^ 0x5c;        this.oHash.update(pad);        pad.fill(0);    }    update(buf) {        assertExists(this);        this.iHash.update(buf);        return this;    }    digestInto(out) {        assertExists(this);        assertBytes(out, this.outputLen);        this.finished = true;        this.iHash.digestInto(out);        this.oHash.update(out);        this.oHash.digestInto(out);        this.destroy();    }    digest() {        const out = new Uint8Array(this.oHash.outputLen);        this.digestInto(out);        return out;    }    _cloneInto(to) {        // Create new instance without calling constructor since key already in state and we don't know it.        to || (to = Object.create(Object.getPrototypeOf(this), {}));        const { oHash, iHash, finished, destroyed, blockLen, outputLen } = this;        to = to;        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;    }    destroy() {        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 */export const hmac = (hash, key, message) => new HMAC(hash, key).update(message).digest();hmac.create = (hash, key) => new HMAC(hash, key);//# sourceMappingURL=hmac.js.map
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