-14297830, -7645148, 16144683, -16471763, 27570974,
-2696100, -26142465, 8378389, 20764389, 8758491
}, by_pieces[] = {
- -26843560, -6710886, 13421773, -13421773, 26843546,
- 6710886, -13421773, 13421773, -26843546, 26843546
+ -26843541, -6710886, 13421773, -13421773, 26843546,
+ 6710886, -13421773, 13421773, -26843546, -6710886
}, d_pieces[] = {
- -10913629, 13857413, -15372611, 6949391, 114729,
- -8787816, -6275908, -3247719, -18696448, 21499316
+ -10913610, 13857413, -15372611, 6949391, 114729,
+ -8787816, -6275908, -3247719, -18696448, -12055116
};
#endif
#if F25519_IMPL == 10
75, 236, -308, 421, 92, 439, -35, 400, 452,
82, -40, 160, 441, -51, 437, -365, 134
}, by_pieces[] = {
- -424, 410, -410, 410, -410, -102, 205, -205, 205,
+ -405, 410, -410, 410, -410, -102, 205, -205, 205,
-205, 205, -410, 410, -410, 410, 102, -205, 205,
- -205, 205, -205, 410, -410, 410, -410, 410
+ -205, 205, -205, 410, -410, 410, -410, -102
}, d_pieces[] = {
- 163, -418, 310, -216, -178, -133, 367, -315, -380,
+ 182, -418, 310, -216, -178, -133, 367, -315, -380,
-351, -182, -255, 2, 152, -390, -136, -52, -383,
- -412, -398, -12, 448, -469, -196, 55, 328
+ -412, -398, -12, 448, -469, -196, 55, -184
};
#endif
static int ptdecode(f25519 *X, f25519 *Y, f25519 *Z, const octet q[32])
{
octet b[32];
+ unsigned i, a;
f25519 t, u;
uint32 m;
- int rc;
+ int rc = 0;
+ /* Load the y-coordinate. */
memcpy(b, q, 32); b[31] &= 0x7fu; f25519_load(Y, b);
+
+ /* Check that the coordinate was in range. If we store it, we'll get a
+ * canonical version which we can compare against Q; be careful not to
+ * check the top bit.
+ */
+ f25519_store(b, Y);
+ for (i = a = 0; i < 31; i++) a |= b[i] ^ q[i];
+ a |= (b[31] ^ q[31])&0x7fu;
+ a = ((a - 1) >> 8)&0x01u; /* 0 |-> 1, non-0 |-> 0 */
+ rc |= (int)a - 1;
+
+ /* Decompress the x-coordinate. */
f25519_sqr(&t, Y); f25519_mul(&u, &t, D); t.P[0] -= 1; u.P[0] += 1;
- rc = f25519_quosqrt(X, &t, &u);
- f25519_store(b, X); m = -(((q[31] >> 7) ^ b[0])&0x1u);
+ rc |= f25519_quosqrt(X, &t, &u);
+ f25519_store(b, X); m = -(uint32)(((q[31] >> 7) ^ b[0])&0x1u);
f25519_condneg(X, X, m);
+
+ /* Set Z. */
f25519_set(Z, 1);
+
+ /* And we're done. */
return (rc);
}
const f25519 *X0, const f25519 *Y0, const f25519 *Z0,
const f25519 *X1, const f25519 *Y1, const f25519 *Z1)
{
- f25519 t0, t1, t2, t3, t4, t5;
+ f25519 t0, t1, t2, t3;
/* Bernstein, Birkner, Joye, Lange, and Peters, `Twisted Edwards Curves',
* 2008-03-13, https://cr.yp.to/newelliptic/twisted-20080313.pdf shows the
*/
f25519_mul(&t0, Z0, Z1); /* t0 = A = Z0 Z1 */
- f25519_sqr(&t1, &t0); /* t1 = B = A^2 */
+ f25519_add(&t1, X0, Y0); /* t1 = X0 + Y0 */
+ f25519_add(&t2, X1, Y1); /* t2 = X1 + Y1 */
+ f25519_mul(&t1, &t1, &t2); /* t1 = (X0 + Y0) (X1 + Y1) */
f25519_mul(&t2, X0, X1); /* t2 = C = X0 X1 */
f25519_mul(&t3, Y0, Y1); /* t3 = D = Y0 Y1 */
- f25519_mul(&t4, &t2, &t3); /* t4 = C D */
- f25519_mul(&t4, &t4, D); /* t4 = E = d C D */
- f25519_sub(&t5, &t1, &t4); /* t5 = F = B - E */
- f25519_add(&t4, &t1, &t4); /* t4 = G = B + E */
- f25519_add(&t1, &t2, &t3); /* t1 = C + D */
- f25519_add(&t2, X0, Y0); /* t2 = X0 + Y0 */
- f25519_add(&t3, X1, Y1); /* t3 = X1 + Y1 */
- f25519_mul(X, &t0, &t5); /* X = A F */
- f25519_mul(Y, &t0, &t4); /* Y = A G */
- f25519_mul(Z, &t5, &t4); /* Z = F G */
- f25519_mul(Y, Y, &t1); /* Y = A G (C + D) = A G (D - a C) */
- f25519_mul(&t0, &t2, &t3); /* t0 = (X0 + Y0) (X1 + Y1) */
- f25519_sub(&t0, &t0, &t1); /* t0 = (X0 + Y0) (X1 + Y1) - C - D */
- f25519_mul(X, X, &t0); /* X = A F ((X0 + Y0) (X1 + Y1) - C - D) */
+ f25519_add(Y, &t2, &t3); /* Y = C + D = D - a C */
+ f25519_sub(X, &t1, Y); /* X = (X0 + Y0) (X1 + Y1) - C - D */
+ f25519_mul(X, X, &t0); /* X = A ((X0 + Y0) (X1 + Y1) - C - D) */
+ f25519_mul(Y, Y, &t0); /* Y = A (D - a C) */
+ f25519_sqr(&t0, &t0); /* t0 = B = A^2 */
+ f25519_mul(&t1, &t2, &t3); /* t1 = C D */
+ f25519_mul(&t1, &t1, D); /* t1 = E = d C D */
+ f25519_sub(&t2, &t0, &t1); /* t2 = F = B - E */
+ f25519_add(&t1, &t0, &t1); /* t1 = G = B + E */
+ f25519_mul(X, X, &t2); /* X = A F ((X0 + Y0) (X1 + Y1) - C - D) */
+ f25519_mul(Y, Y, &t1); /* Y = A G (D - a C) */
+ f25519_mul(Z, &t1, &t2); /* Z = F G */
}
static void ptdbl(f25519 *X, f25519 *Y, f25519 *Z,
sha512_init(&h); sha512_hash(&h, k, ksz); sha512_done(&h, b);
b[0] &= 0xf8u; b[31] = (b[31]&0x3f) | 0x40;
scaf_load(a, b, 32, NPIECE, PIECEWD);
- memcpy(h1, b + 32, 32);
+ if (h1) memcpy(h1, b + 32, 32);
}
/*----- Main code ---------------------------------------------------------*/
{
scaf_piece a[NPIECE];
f25519 AX, AY, AZ;
- octet h1[32];
- unpack_key(a, h1, k, ksz);
+ unpack_key(a, 0, k, ksz);
ptmul(&AX, &AY, &AZ, a, BX, BY, BZ);
ptencode(K, &AX, &AY, &AZ);
}
if (ptdecode(&AX, &AY, &AZ, K)) return (-1);
f25519_neg(&AX, &AX);
+ /* Load the scalar and check that it's in range. The easy way is to store
+ * it again and see if the two match.
+ */
+ scaf_loaddbl(tt, sig + 32, 32, 2*NPIECE, PIECEWD);
+ scaf_reduce(s, tt, l, mu, NPIECE, PIECEWD, scratch);
+ scaf_store(b, 32, s, NPIECE, PIECEWD);
+ if (memcmp(b, sig + 32, 32) != 0) return (-1);
+
/* Check the signature. */
sha512_init(&h);
sha512_hash(&h, sig, 32);
sha512_hash(&h, K, 32);
sha512_hash(&h, m, msz);
sha512_done(&h, b);
- scaf_load(s, sig + 32, 32, NPIECE, PIECEWD);
scaf_loaddbl(tt, b, 64, 2*NPIECE, PIECEWD);
scaf_reduce(t, tt, l, mu, NPIECE, PIECEWD, scratch);
ptsimmul(&RX, &RY, &RZ, s, BX, BY, BZ, t, &AX, &AY, &AZ);
dstr dpub = DSTR_INIT;
int ok = 1;
- if (dv[1].len != 32) die(1, "bad pub length");
+ if (dv[1].len != ED25519_PUBSZ) die(1, "bad pub length");
- dstr_ensure(&dpub, 32); dpub.len = 32;
+ dstr_ensure(&dpub, ED25519_PUBSZ); dpub.len = ED25519_PUBSZ;
ed25519_pubkey((octet *)dpub.buf, dv[0].buf, dv[0].len);
- if (memcmp(dpub.buf, dv[1].buf, 64) != 0) {
+ if (memcmp(dpub.buf, dv[1].buf, ED25519_PUBSZ) != 0) {
ok = 0;
fprintf(stderr, "failed!");
fprintf(stderr, "\n\tpriv = "); type_hex.dump(&dv[0], stderr);
dstr dsig = DSTR_INIT;
int ok = 1;
- if (dv[2].len != 64) die(1, "bad result length");
+ if (dv[2].len != ED25519_SIGSZ) die(1, "bad result length");
- dstr_ensure(&dsig, 64); dsig.len = 64;
+ dstr_ensure(&dsig, ED25519_SIGSZ); dsig.len = ED25519_SIGSZ;
ed25519_pubkey(K, dv[0].buf, dv[0].len);
ed25519_sign((octet *)dsig.buf, dv[0].buf, dv[0].len, K,
dv[1].buf, dv[1].len);
- if (memcmp(dsig.buf, dv[2].buf, 64) != 0) {
+ if (memcmp(dsig.buf, dv[2].buf, ED25519_SIGSZ) != 0) {
ok = 0;
fprintf(stderr, "failed!");
fprintf(stderr, "\n\tpriv = "); type_hex.dump(&dv[0], stderr);
int rc_want, rc_calc;
int ok = 1;
- if (dv[0].len != 32) die(1, "bad pub length");
- if (dv[2].len != 64) die(1, "bad sig length");
+ if (dv[0].len != ED25519_PUBSZ) die(1, "bad pub length");
+ if (dv[2].len != ED25519_SIGSZ) die(1, "bad sig length");
rc_want = *(int *)dv[3].buf;
rc_calc = ed25519_verify((const octet *)dv[0].buf,
~mdw / catacomb / blobdiff