ccxt
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101 lines (96 loc) • 4.52 kB
JavaScript
;
Object.defineProperty(exports, '__esModule', { value: true });
var modular = require('./modular.js');
// ----------------------------------------------------------------------------
function validateOpts(opts) {
const { Fp } = opts;
modular.validateField(Fp);
for (const i of ['t', 'roundsFull', 'roundsPartial']) {
if (typeof opts[i] !== 'number' || !Number.isSafeInteger(opts[i]))
throw new Error(`Poseidon: invalid param ${i}=${opts[i]} (${typeof opts[i]})`);
}
if (opts.reversePartialPowIdx !== undefined && typeof opts.reversePartialPowIdx !== 'boolean')
throw new Error(`Poseidon: invalid param reversePartialPowIdx=${opts.reversePartialPowIdx}`);
// Default is 5, but by some reasons stark uses 3
let sboxPower = opts.sboxPower;
if (sboxPower === undefined)
sboxPower = 5;
if (typeof sboxPower !== 'number' || !Number.isSafeInteger(sboxPower))
throw new Error(`Poseidon wrong sboxPower=${sboxPower}`);
const _sboxPower = BigInt(sboxPower);
let sboxFn = (n) => modular.FpPow(Fp, n, _sboxPower);
// Unwrapped sbox power for common cases (195->142μs)
if (sboxPower === 3)
sboxFn = (n) => Fp.mul(Fp.sqrN(n), n);
else if (sboxPower === 5)
sboxFn = (n) => Fp.mul(Fp.sqrN(Fp.sqrN(n)), n);
if (opts.roundsFull % 2 !== 0)
throw new Error(`Poseidon roundsFull is not even: ${opts.roundsFull}`);
const rounds = opts.roundsFull + opts.roundsPartial;
if (!Array.isArray(opts.roundConstants) || opts.roundConstants.length !== rounds)
throw new Error('Poseidon: wrong round constants');
const roundConstants = opts.roundConstants.map((rc) => {
if (!Array.isArray(rc) || rc.length !== opts.t)
throw new Error(`Poseidon wrong round constants: ${rc}`);
return rc.map((i) => {
if (typeof i !== 'bigint' || !Fp.isValid(i))
throw new Error(`Poseidon wrong round constant=${i}`);
return Fp.create(i);
});
});
// MDS is TxT matrix
if (!Array.isArray(opts.mds) || opts.mds.length !== opts.t)
throw new Error('Poseidon: wrong MDS matrix');
const mds = opts.mds.map((mdsRow) => {
if (!Array.isArray(mdsRow) || mdsRow.length !== opts.t)
throw new Error(`Poseidon MDS matrix row: ${mdsRow}`);
return mdsRow.map((i) => {
if (typeof i !== 'bigint')
throw new Error(`Poseidon MDS matrix value=${i}`);
return Fp.create(i);
});
});
return Object.freeze({ ...opts, rounds, sboxFn, roundConstants, mds });
}
function poseidon(opts) {
const { t, Fp, rounds, sboxFn, reversePartialPowIdx } = validateOpts(opts);
const halfRoundsFull = Math.floor(opts.roundsFull / 2);
const partialIdx = reversePartialPowIdx ? t - 1 : 0;
const poseidonRound = (values, isFull, idx) => {
values = values.map((i, j) => Fp.add(i, opts.roundConstants[idx][j]));
if (isFull)
values = values.map((i) => sboxFn(i));
else
values[partialIdx] = sboxFn(values[partialIdx]);
// Matrix multiplication
values = opts.mds.map((i) => i.reduce((acc, i, j) => Fp.add(acc, Fp.mulN(i, values[j])), Fp.ZERO));
return values;
};
const poseidonHash = function poseidonHash(values) {
if (!Array.isArray(values) || values.length !== t)
throw new Error(`Poseidon: wrong values (expected array of bigints with length ${t})`);
values = values.map((i) => {
if (typeof i !== 'bigint')
throw new Error(`Poseidon: wrong value=${i} (${typeof i})`);
return Fp.create(i);
});
let round = 0;
// Apply r_f/2 full rounds.
for (let i = 0; i < halfRoundsFull; i++)
values = poseidonRound(values, true, round++);
// Apply r_p partial rounds.
for (let i = 0; i < opts.roundsPartial; i++)
values = poseidonRound(values, false, round++);
// Apply r_f/2 full rounds.
for (let i = 0; i < halfRoundsFull; i++)
values = poseidonRound(values, true, round++);
if (round !== rounds)
throw new Error(`Poseidon: wrong number of rounds: last round=${round}, total=${rounds}`);
return values;
};
// For verification in tests
poseidonHash.roundConstants = opts.roundConstants;
return poseidonHash;
}
exports.poseidon = poseidon;
exports.validateOpts = validateOpts;