add crypto_core methods

This commit is contained in:
Christophe Diederichs 2022-11-18 08:56:18 +00:00
parent 58947e04ce
commit c42c442eab

272
crypto_core.js Normal file
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const b4a = require('b4a')
const assert = require('nanoassert')
const {
ge25519_p3,
ge25519_p1p1,
ge25519_cached,
ge25519_frombytes,
ge25519_p3_tobytes,
ge25519_p1p1_to_p3,
ge25519_p3_to_cached,
ge25519_is_on_curve,
ge25519_is_canonical,
ge25519_is_on_main_subgroup,
ge25519_has_small_order,
ge25519_add_cached,
ge25519_sub_cached,
ge25519_from_uniform,
sc25519_reduce,
sc25519_mul,
sc25519_invert,
sc25519_is_canonical
} = require('./fe25519_25.js')
const { randombytes_buf } = require('./randombytes')
const {
sodium_add,
sodium_sub,
sodium_is_zero,
sodium_memzero
} = require('./utils')
function crypto_core_ed25519_is_valid_point (p) {
const p_p3 = ge25519_p3()
if (ge25519_is_canonical(p) == 0 ||
ge25519_has_small_order(p) != 0 ||
ge25519_frombytes(p_p3, p) != 0 ||
ge25519_is_on_curve(p_p3) == 0 ||
ge25519_is_on_main_subgroup(p_p3) == 0) {
return 0;
}
return 1;
}
function crypto_core_ed25519_add (r, p, q) {
const p_p3 = ge25519_p3()
const q_p3 = ge25519_p3()
const r_p3 = ge25519_p3()
const r_p1p1 = ge25519_p1p1()
const q_cached = ge25519_cached()
if (ge25519_frombytes(p_p3, p) != 0 || ge25519_is_on_curve(p_p3) == 0 ||
ge25519_frombytes(q_p3, q) != 0 || ge25519_is_on_curve(q_p3) == 0) {
throw new Error('Operands must be valid points.')
}
ge25519_p3_to_cached(q_cached, q_p3)
ge25519_add_cached(r_p1p1, p_p3, q_cached)
ge25519_p1p1_to_p3(r_p3, r_p1p1)
ge25519_p3_tobytes(r, r_p3)
}
function crypto_core_ed25519_sub (r, p, q) {
const p_p3 = ge25519_p3()
const q_p3 = ge25519_p3()
const r_p3 = ge25519_p3()
const r_p1p1 = ge25519_p1p1()
const q_cached = ge25519_cached()
if (ge25519_frombytes(p_p3, p) != 0 || ge25519_is_on_curve(p_p3) == 0 ||
ge25519_frombytes(q_p3, q) != 0 || ge25519_is_on_curve(q_p3) == 0) {
throw new Error('Operands must be valid points.')
}
ge25519_p3_to_cached(q_cached, q_p3);
ge25519_sub_cached(r_p1p1, p_p3, q_cached);
ge25519_p1p1_to_p3(r_p3, r_p1p1);
ge25519_p3_tobytes(r, r_p3);
}
function crypto_core_ed25519_from_uniform (p, r) {
ge25519_from_uniform(p, r)
}
// const HASH_GE_L = 48
// function _string_to_points (px, n, ctx, msg, msg_len, hash_alg) {
// const h = b4a.alloc(crypto_core_ed25519_HASHBYTES)
// const h_be = b4a.alloc(2 * HASH_GE_L)
// let i
// let j
// if (n > 2) {
// // abort(); /* LCOV_EXCL_LINE */
// throw new Error('abort')
// }
// if (core_h2c_string_to_hash(h_be, n * HASH_GE_L, ctx, msg, msg_len,
// hash_alg) != 0) {
// return -1;
// }
// COMPILER_ASSERT(sizeof h >= HASH_GE_L);
// for (i = 0U; i < n; i++) {
// for (j = 0U; j < HASH_GE_L; j++) {
// h[j] = h_be[i * HASH_GE_L + HASH_GE_L - 1U - j];
// }
// memset(&h[j], 0, (sizeof h) - j);
// ge25519_from_hash(&px[i * crypto_core_ed25519_BYTES], h);
// }
// return 0;
// }
// int
// crypto_core_ed25519_from_string(unsigned char p[crypto_core_ed25519_BYTES],
// const char *ctx, msg,
// size_t msg_len, int hash_alg)
// {
// return _string_to_points(p, 1, ctx, msg, msg_len, hash_alg);
// }
// int
// crypto_core_ed25519_from_string_ro(unsigned char p[crypto_core_ed25519_BYTES],
// const char *ctx, msg,
// size_t msg_len, int hash_alg)
// {
// unsigned char px[2 * crypto_core_ed25519_BYTES];
// if (_string_to_points(px, 2, ctx, msg, msg_len, hash_alg) != 0) {
// return -1;
// }
// return crypto_core_ed25519_add(p, &px[0], &px[crypto_core_ed25519_BYTES]);
// }
function crypto_core_ed25519_random (p) {
const h = b4a.alloc(crypto_core_ed25519_UNIFORMBYTES)
randombytes_buf(h)
crypto_core_ed25519_from_uniform(p, h)
}
function crypto_core_ed25519_scalar_random (r) {
do {
randombytes_buf(r, crypto_core_ed25519_SCALARBYTES)
r[crypto_core_ed25519_SCALARBYTES - 1] &= 0x1f
} while (sc25519_is_canonical(r) == 0 ||
sodium_is_zero(r, crypto_core_ed25519_SCALARBYTES));
}
function crypto_core_ed25519_scalar_invert (recip, s) {
console.log(s)
sc25519_invert(recip, s)
console.log(recip)
if (sodium_is_zero(s, crypto_core_ed25519_SCALARBYTES)) {
throw new Error('Zero point')
}
}
/* 2^252+27742317777372353535851937790883648493 */
const L = b4a.from([
0xed, 0xd3, 0xf5, 0x5c, 0x1a, 0x63, 0x12, 0x58, 0xd6, 0x9c, 0xf7,
0xa2, 0xde, 0xf9, 0xde, 0x14, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10
])
function crypto_core_ed25519_scalar_negate (neg, s) {
const t_ = b4a.alloc(crypto_core_ed25519_NONREDUCEDSCALARBYTES)
const s_ = b4a.alloc(crypto_core_ed25519_NONREDUCEDSCALARBYTES)
assert(crypto_core_ed25519_NONREDUCEDSCALARBYTES >=
2 * crypto_core_ed25519_SCALARBYTES);
t_.fill(0)
s_.fill(0)
t_.set(L.subarray(crypto_core_ed25519_SCALARBYTES, crypto_core_ed25519_SCALARBYTES))
s_.set(s.subarray(0, crypto_core_ed25519_SCALARBYTES))
sodium_sub(t_, s_, crypto_core_ed25519_SCALARBYTES)
sc25519_reduce(t_)
neg.set(t_.subarray(0 , crypto_core_ed25519_SCALARBYTES))
}
function crypto_core_ed25519_scalar_complement (comp, s) {
const t_ = b4a.alloc(crypto_core_ed25519_NONREDUCEDSCALARBYTES)
const s_ = b4a.alloc(crypto_core_ed25519_NONREDUCEDSCALARBYTES)
assert(crypto_core_ed25519_NONREDUCEDSCALARBYTES >=
2 * crypto_core_ed25519_SCALARBYTES);
t_.fill(0)
s_.fill(0)
t_[0]++;
t_.set(L.subarray(crypto_core_ed25519_SCALARBYTES, crypto_core_ed25519_SCALARBYTES))
s_.set(s.subarray(0, crypto_core_ed25519_SCALARBYTES))
sodium_sub(t_, s_, crypto_core_ed25519_SCALARBYTES)
sc25519_reduce(t_)
comp.set(t_.subarray(0, crypto_core_ed25519_SCALARBYTES))
}
function crypto_core_ed25519_scalar_add (z, x, y) {
const x_ = b4a.alloc(crypto_core_ed25519_NONREDUCEDSCALARBYTES)
const y_ = b4a.alloc(crypto_core_ed25519_NONREDUCEDSCALARBYTES)
x_.fill(0)
y_.fill(0)
x_.set(x.subarray(0, crypto_core_ed25519_SCALARBYTES))
y_.set(y.subarray(0, crypto_core_ed25519_SCALARBYTES))
sodium_add(x_, y_, crypto_core_ed25519_SCALARBYTES)
crypto_core_ed25519_scalar_reduce(z, x_)
}
function crypto_core_ed25519_scalar_sub(z, x, y) {
const yn = b4a.alloc(crypto_core_ed25519_SCALARBYTES)
crypto_core_ed25519_scalar_negate(yn, y)
crypto_core_ed25519_scalar_add(z, x, yn)
}
function crypto_core_ed25519_scalar_mul(z, x, y) {
sc25519_mul(z, x, y)
}
function crypto_core_ed25519_scalar_reduce(r, s) {
const t = b4a.alloc(crypto_core_ed25519_NONREDUCEDSCALARBYTES)
t.set(s)
sc25519_reduce(t)
r.set(t.subarray(0, crypto_core_ed25519_SCALARBYTES))
sodium_memzero(t)
}
function crypto_core_ed25519_scalar_is_canonical(s) {
return sc25519_is_canonical(s)
}
const crypto_core_ed25519_BYTES = 32
const crypto_core_ed25519_UNIFORMBYTES = 32
const crypto_core_ed25519_SCALARBYTES = 32
const crypto_core_ed25519_NONREDUCEDSCALARBYTES = 64
module.exports = {
crypto_core_ed25519_is_valid_point,
crypto_core_ed25519_add,
crypto_core_ed25519_sub,
crypto_core_ed25519_from_uniform,
crypto_core_ed25519_random,
crypto_core_ed25519_scalar_random,
crypto_core_ed25519_scalar_invert,
crypto_core_ed25519_scalar_negate,
crypto_core_ed25519_scalar_complement,
crypto_core_ed25519_scalar_add,
crypto_core_ed25519_scalar_sub,
crypto_core_ed25519_scalar_mul,
crypto_core_ed25519_scalar_reduce,
crypto_core_ed25519_scalar_is_canonical,
crypto_core_ed25519_BYTES,
crypto_core_ed25519_UNIFORMBYTES,
crypto_core_ed25519_SCALARBYTES,
crypto_core_ed25519_NONREDUCEDSCALARBYTES
}