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crypto: ecc - Add math to support fast NIST P384
Add the math needed for NIST P384 and adapt certain functions' parameters so that the ecc_curve is passed to vli_mmod_fast. This allows to identify the curve by its name prefix and the appropriate function for fast mmod calculation can be used. Summary of changes: * crypto/ecc.c - add vli_mmod_fast_384 - change some routines to pass ecc_curve forward until vli_mmod_fast * crypto/ecc.h - add ECC_CURVE_NIST_P384_DIGITS - change ECC_MAX_DIGITS to P384 size Signed-off-by: Saulo Alessandre <saulo.alessandre@tse.jus.br> Tested-by: Stefan Berger <stefanb@linux.ibm.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Saulo Alessandre
Herbert Xu
parent
703c748d5f
commit
149ca1611d
266
crypto/ecc.c
266
crypto/ecc.c
@ -778,18 +778,133 @@ static void vli_mmod_fast_256(u64 *result, const u64 *product,
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}
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}
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#define SL32OR32(x32, y32) (((u64)x32 << 32) | y32)
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#define AND64H(x64) (x64 & 0xffFFffFF00000000ull)
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#define AND64L(x64) (x64 & 0x00000000ffFFffFFull)
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/* Computes result = product % curve_prime
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* from "Mathematical routines for the NIST prime elliptic curves"
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*/
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static void vli_mmod_fast_384(u64 *result, const u64 *product,
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const u64 *curve_prime, u64 *tmp)
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{
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int carry;
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const unsigned int ndigits = 6;
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/* t */
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vli_set(result, product, ndigits);
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/* s1 */
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tmp[0] = 0; // 0 || 0
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tmp[1] = 0; // 0 || 0
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tmp[2] = SL32OR32(product[11], (product[10]>>32)); //a22||a21
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tmp[3] = product[11]>>32; // 0 ||a23
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tmp[4] = 0; // 0 || 0
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tmp[5] = 0; // 0 || 0
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carry = vli_lshift(tmp, tmp, 1, ndigits);
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carry += vli_add(result, result, tmp, ndigits);
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/* s2 */
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tmp[0] = product[6]; //a13||a12
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tmp[1] = product[7]; //a15||a14
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tmp[2] = product[8]; //a17||a16
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tmp[3] = product[9]; //a19||a18
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tmp[4] = product[10]; //a21||a20
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tmp[5] = product[11]; //a23||a22
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carry += vli_add(result, result, tmp, ndigits);
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/* s3 */
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tmp[0] = SL32OR32(product[11], (product[10]>>32)); //a22||a21
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tmp[1] = SL32OR32(product[6], (product[11]>>32)); //a12||a23
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tmp[2] = SL32OR32(product[7], (product[6])>>32); //a14||a13
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tmp[3] = SL32OR32(product[8], (product[7]>>32)); //a16||a15
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tmp[4] = SL32OR32(product[9], (product[8]>>32)); //a18||a17
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tmp[5] = SL32OR32(product[10], (product[9]>>32)); //a20||a19
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carry += vli_add(result, result, tmp, ndigits);
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/* s4 */
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tmp[0] = AND64H(product[11]); //a23|| 0
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tmp[1] = (product[10]<<32); //a20|| 0
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tmp[2] = product[6]; //a13||a12
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tmp[3] = product[7]; //a15||a14
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tmp[4] = product[8]; //a17||a16
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tmp[5] = product[9]; //a19||a18
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carry += vli_add(result, result, tmp, ndigits);
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/* s5 */
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tmp[0] = 0; // 0|| 0
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tmp[1] = 0; // 0|| 0
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tmp[2] = product[10]; //a21||a20
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tmp[3] = product[11]; //a23||a22
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tmp[4] = 0; // 0|| 0
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tmp[5] = 0; // 0|| 0
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carry += vli_add(result, result, tmp, ndigits);
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/* s6 */
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tmp[0] = AND64L(product[10]); // 0 ||a20
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tmp[1] = AND64H(product[10]); //a21|| 0
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tmp[2] = product[11]; //a23||a22
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tmp[3] = 0; // 0 || 0
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tmp[4] = 0; // 0 || 0
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tmp[5] = 0; // 0 || 0
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carry += vli_add(result, result, tmp, ndigits);
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/* d1 */
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tmp[0] = SL32OR32(product[6], (product[11]>>32)); //a12||a23
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tmp[1] = SL32OR32(product[7], (product[6]>>32)); //a14||a13
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tmp[2] = SL32OR32(product[8], (product[7]>>32)); //a16||a15
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tmp[3] = SL32OR32(product[9], (product[8]>>32)); //a18||a17
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tmp[4] = SL32OR32(product[10], (product[9]>>32)); //a20||a19
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tmp[5] = SL32OR32(product[11], (product[10]>>32)); //a22||a21
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carry -= vli_sub(result, result, tmp, ndigits);
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/* d2 */
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tmp[0] = (product[10]<<32); //a20|| 0
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tmp[1] = SL32OR32(product[11], (product[10]>>32)); //a22||a21
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tmp[2] = (product[11]>>32); // 0 ||a23
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tmp[3] = 0; // 0 || 0
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tmp[4] = 0; // 0 || 0
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tmp[5] = 0; // 0 || 0
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carry -= vli_sub(result, result, tmp, ndigits);
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/* d3 */
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tmp[0] = 0; // 0 || 0
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tmp[1] = AND64H(product[11]); //a23|| 0
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tmp[2] = product[11]>>32; // 0 ||a23
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tmp[3] = 0; // 0 || 0
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tmp[4] = 0; // 0 || 0
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tmp[5] = 0; // 0 || 0
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carry -= vli_sub(result, result, tmp, ndigits);
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if (carry < 0) {
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do {
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carry += vli_add(result, result, curve_prime, ndigits);
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} while (carry < 0);
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} else {
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while (carry || vli_cmp(curve_prime, result, ndigits) != 1)
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carry -= vli_sub(result, result, curve_prime, ndigits);
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}
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}
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#undef SL32OR32
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#undef AND64H
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#undef AND64L
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/* Computes result = product % curve_prime for different curve_primes.
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*
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* Note that curve_primes are distinguished just by heuristic check and
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* not by complete conformance check.
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*/
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static bool vli_mmod_fast(u64 *result, u64 *product,
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const u64 *curve_prime, unsigned int ndigits)
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const struct ecc_curve *curve)
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{
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u64 tmp[2 * ECC_MAX_DIGITS];
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const u64 *curve_prime = curve->p;
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const unsigned int ndigits = curve->g.ndigits;
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/* Currently, both NIST primes have -1 in lowest qword. */
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if (curve_prime[0] != -1ull) {
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/* All NIST curves have name prefix 'nist_' */
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if (strncmp(curve->name, "nist_", 5) != 0) {
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/* Try to handle Pseudo-Marsenne primes. */
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if (curve_prime[ndigits - 1] == -1ull) {
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vli_mmod_special(result, product, curve_prime,
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@ -812,6 +927,9 @@ static bool vli_mmod_fast(u64 *result, u64 *product,
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case 4:
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vli_mmod_fast_256(result, product, curve_prime, tmp);
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break;
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case 6:
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vli_mmod_fast_384(result, product, curve_prime, tmp);
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break;
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default:
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pr_err_ratelimited("ecc: unsupported digits size!\n");
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return false;
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@ -835,22 +953,22 @@ EXPORT_SYMBOL(vli_mod_mult_slow);
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/* Computes result = (left * right) % curve_prime. */
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static void vli_mod_mult_fast(u64 *result, const u64 *left, const u64 *right,
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const u64 *curve_prime, unsigned int ndigits)
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const struct ecc_curve *curve)
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{
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u64 product[2 * ECC_MAX_DIGITS];
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vli_mult(product, left, right, ndigits);
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vli_mmod_fast(result, product, curve_prime, ndigits);
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vli_mult(product, left, right, curve->g.ndigits);
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vli_mmod_fast(result, product, curve);
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}
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/* Computes result = left^2 % curve_prime. */
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static void vli_mod_square_fast(u64 *result, const u64 *left,
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const u64 *curve_prime, unsigned int ndigits)
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const struct ecc_curve *curve)
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{
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u64 product[2 * ECC_MAX_DIGITS];
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vli_square(product, left, ndigits);
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vli_mmod_fast(result, product, curve_prime, ndigits);
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vli_square(product, left, curve->g.ndigits);
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vli_mmod_fast(result, product, curve);
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}
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#define EVEN(vli) (!(vli[0] & 1))
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@ -948,25 +1066,27 @@ static bool ecc_point_is_zero(const struct ecc_point *point)
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/* Double in place */
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static void ecc_point_double_jacobian(u64 *x1, u64 *y1, u64 *z1,
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u64 *curve_prime, unsigned int ndigits)
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const struct ecc_curve *curve)
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{
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/* t1 = x, t2 = y, t3 = z */
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u64 t4[ECC_MAX_DIGITS];
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u64 t5[ECC_MAX_DIGITS];
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const u64 *curve_prime = curve->p;
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const unsigned int ndigits = curve->g.ndigits;
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if (vli_is_zero(z1, ndigits))
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return;
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/* t4 = y1^2 */
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vli_mod_square_fast(t4, y1, curve_prime, ndigits);
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vli_mod_square_fast(t4, y1, curve);
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/* t5 = x1*y1^2 = A */
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vli_mod_mult_fast(t5, x1, t4, curve_prime, ndigits);
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vli_mod_mult_fast(t5, x1, t4, curve);
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/* t4 = y1^4 */
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vli_mod_square_fast(t4, t4, curve_prime, ndigits);
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vli_mod_square_fast(t4, t4, curve);
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/* t2 = y1*z1 = z3 */
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vli_mod_mult_fast(y1, y1, z1, curve_prime, ndigits);
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vli_mod_mult_fast(y1, y1, z1, curve);
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/* t3 = z1^2 */
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vli_mod_square_fast(z1, z1, curve_prime, ndigits);
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vli_mod_square_fast(z1, z1, curve);
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/* t1 = x1 + z1^2 */
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vli_mod_add(x1, x1, z1, curve_prime, ndigits);
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@ -975,7 +1095,7 @@ static void ecc_point_double_jacobian(u64 *x1, u64 *y1, u64 *z1,
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/* t3 = x1 - z1^2 */
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vli_mod_sub(z1, x1, z1, curve_prime, ndigits);
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/* t1 = x1^2 - z1^4 */
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vli_mod_mult_fast(x1, x1, z1, curve_prime, ndigits);
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vli_mod_mult_fast(x1, x1, z1, curve);
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/* t3 = 2*(x1^2 - z1^4) */
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vli_mod_add(z1, x1, x1, curve_prime, ndigits);
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@ -992,7 +1112,7 @@ static void ecc_point_double_jacobian(u64 *x1, u64 *y1, u64 *z1,
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/* t1 = 3/2*(x1^2 - z1^4) = B */
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/* t3 = B^2 */
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vli_mod_square_fast(z1, x1, curve_prime, ndigits);
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vli_mod_square_fast(z1, x1, curve);
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/* t3 = B^2 - A */
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vli_mod_sub(z1, z1, t5, curve_prime, ndigits);
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/* t3 = B^2 - 2A = x3 */
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@ -1000,7 +1120,7 @@ static void ecc_point_double_jacobian(u64 *x1, u64 *y1, u64 *z1,
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/* t5 = A - x3 */
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vli_mod_sub(t5, t5, z1, curve_prime, ndigits);
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/* t1 = B * (A - x3) */
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vli_mod_mult_fast(x1, x1, t5, curve_prime, ndigits);
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vli_mod_mult_fast(x1, x1, t5, curve);
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/* t4 = B * (A - x3) - y1^4 = y3 */
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vli_mod_sub(t4, x1, t4, curve_prime, ndigits);
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@ -1010,23 +1130,22 @@ static void ecc_point_double_jacobian(u64 *x1, u64 *y1, u64 *z1,
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}
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/* Modify (x1, y1) => (x1 * z^2, y1 * z^3) */
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static void apply_z(u64 *x1, u64 *y1, u64 *z, u64 *curve_prime,
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unsigned int ndigits)
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static void apply_z(u64 *x1, u64 *y1, u64 *z, const struct ecc_curve *curve)
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{
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u64 t1[ECC_MAX_DIGITS];
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vli_mod_square_fast(t1, z, curve_prime, ndigits); /* z^2 */
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vli_mod_mult_fast(x1, x1, t1, curve_prime, ndigits); /* x1 * z^2 */
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vli_mod_mult_fast(t1, t1, z, curve_prime, ndigits); /* z^3 */
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vli_mod_mult_fast(y1, y1, t1, curve_prime, ndigits); /* y1 * z^3 */
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vli_mod_square_fast(t1, z, curve); /* z^2 */
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vli_mod_mult_fast(x1, x1, t1, curve); /* x1 * z^2 */
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vli_mod_mult_fast(t1, t1, z, curve); /* z^3 */
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vli_mod_mult_fast(y1, y1, t1, curve); /* y1 * z^3 */
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}
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/* P = (x1, y1) => 2P, (x2, y2) => P' */
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static void xycz_initial_double(u64 *x1, u64 *y1, u64 *x2, u64 *y2,
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u64 *p_initial_z, u64 *curve_prime,
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unsigned int ndigits)
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u64 *p_initial_z, const struct ecc_curve *curve)
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{
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u64 z[ECC_MAX_DIGITS];
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const unsigned int ndigits = curve->g.ndigits;
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vli_set(x2, x1, ndigits);
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vli_set(y2, y1, ndigits);
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@ -1037,35 +1156,37 @@ static void xycz_initial_double(u64 *x1, u64 *y1, u64 *x2, u64 *y2,
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if (p_initial_z)
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vli_set(z, p_initial_z, ndigits);
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apply_z(x1, y1, z, curve_prime, ndigits);
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apply_z(x1, y1, z, curve);
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ecc_point_double_jacobian(x1, y1, z, curve_prime, ndigits);
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ecc_point_double_jacobian(x1, y1, z, curve);
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apply_z(x2, y2, z, curve_prime, ndigits);
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apply_z(x2, y2, z, curve);
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}
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/* Input P = (x1, y1, Z), Q = (x2, y2, Z)
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* Output P' = (x1', y1', Z3), P + Q = (x3, y3, Z3)
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* or P => P', Q => P + Q
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*/
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static void xycz_add(u64 *x1, u64 *y1, u64 *x2, u64 *y2, u64 *curve_prime,
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unsigned int ndigits)
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static void xycz_add(u64 *x1, u64 *y1, u64 *x2, u64 *y2,
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const struct ecc_curve *curve)
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{
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/* t1 = X1, t2 = Y1, t3 = X2, t4 = Y2 */
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u64 t5[ECC_MAX_DIGITS];
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const u64 *curve_prime = curve->p;
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const unsigned int ndigits = curve->g.ndigits;
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/* t5 = x2 - x1 */
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vli_mod_sub(t5, x2, x1, curve_prime, ndigits);
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/* t5 = (x2 - x1)^2 = A */
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vli_mod_square_fast(t5, t5, curve_prime, ndigits);
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vli_mod_square_fast(t5, t5, curve);
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/* t1 = x1*A = B */
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vli_mod_mult_fast(x1, x1, t5, curve_prime, ndigits);
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vli_mod_mult_fast(x1, x1, t5, curve);
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/* t3 = x2*A = C */
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vli_mod_mult_fast(x2, x2, t5, curve_prime, ndigits);
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vli_mod_mult_fast(x2, x2, t5, curve);
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/* t4 = y2 - y1 */
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vli_mod_sub(y2, y2, y1, curve_prime, ndigits);
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/* t5 = (y2 - y1)^2 = D */
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vli_mod_square_fast(t5, y2, curve_prime, ndigits);
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vli_mod_square_fast(t5, y2, curve);
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/* t5 = D - B */
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vli_mod_sub(t5, t5, x1, curve_prime, ndigits);
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@ -1074,11 +1195,11 @@ static void xycz_add(u64 *x1, u64 *y1, u64 *x2, u64 *y2, u64 *curve_prime,
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/* t3 = C - B */
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vli_mod_sub(x2, x2, x1, curve_prime, ndigits);
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/* t2 = y1*(C - B) */
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vli_mod_mult_fast(y1, y1, x2, curve_prime, ndigits);
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vli_mod_mult_fast(y1, y1, x2, curve);
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/* t3 = B - x3 */
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vli_mod_sub(x2, x1, t5, curve_prime, ndigits);
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/* t4 = (y2 - y1)*(B - x3) */
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vli_mod_mult_fast(y2, y2, x2, curve_prime, ndigits);
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vli_mod_mult_fast(y2, y2, x2, curve);
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/* t4 = y3 */
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vli_mod_sub(y2, y2, y1, curve_prime, ndigits);
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@ -1089,22 +1210,24 @@ static void xycz_add(u64 *x1, u64 *y1, u64 *x2, u64 *y2, u64 *curve_prime,
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* Output P + Q = (x3, y3, Z3), P - Q = (x3', y3', Z3)
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* or P => P - Q, Q => P + Q
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*/
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static void xycz_add_c(u64 *x1, u64 *y1, u64 *x2, u64 *y2, u64 *curve_prime,
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unsigned int ndigits)
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static void xycz_add_c(u64 *x1, u64 *y1, u64 *x2, u64 *y2,
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const struct ecc_curve *curve)
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{
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/* t1 = X1, t2 = Y1, t3 = X2, t4 = Y2 */
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u64 t5[ECC_MAX_DIGITS];
|
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u64 t6[ECC_MAX_DIGITS];
|
||||
u64 t7[ECC_MAX_DIGITS];
|
||||
const u64 *curve_prime = curve->p;
|
||||
const unsigned int ndigits = curve->g.ndigits;
|
||||
|
||||
/* t5 = x2 - x1 */
|
||||
vli_mod_sub(t5, x2, x1, curve_prime, ndigits);
|
||||
/* t5 = (x2 - x1)^2 = A */
|
||||
vli_mod_square_fast(t5, t5, curve_prime, ndigits);
|
||||
vli_mod_square_fast(t5, t5, curve);
|
||||
/* t1 = x1*A = B */
|
||||
vli_mod_mult_fast(x1, x1, t5, curve_prime, ndigits);
|
||||
vli_mod_mult_fast(x1, x1, t5, curve);
|
||||
/* t3 = x2*A = C */
|
||||
vli_mod_mult_fast(x2, x2, t5, curve_prime, ndigits);
|
||||
vli_mod_mult_fast(x2, x2, t5, curve);
|
||||
/* t4 = y2 + y1 */
|
||||
vli_mod_add(t5, y2, y1, curve_prime, ndigits);
|
||||
/* t4 = y2 - y1 */
|
||||
@ -1113,29 +1236,29 @@ static void xycz_add_c(u64 *x1, u64 *y1, u64 *x2, u64 *y2, u64 *curve_prime,
|
||||
/* t6 = C - B */
|
||||
vli_mod_sub(t6, x2, x1, curve_prime, ndigits);
|
||||
/* t2 = y1 * (C - B) */
|
||||
vli_mod_mult_fast(y1, y1, t6, curve_prime, ndigits);
|
||||
vli_mod_mult_fast(y1, y1, t6, curve);
|
||||
/* t6 = B + C */
|
||||
vli_mod_add(t6, x1, x2, curve_prime, ndigits);
|
||||
/* t3 = (y2 - y1)^2 */
|
||||
vli_mod_square_fast(x2, y2, curve_prime, ndigits);
|
||||
vli_mod_square_fast(x2, y2, curve);
|
||||
/* t3 = x3 */
|
||||
vli_mod_sub(x2, x2, t6, curve_prime, ndigits);
|
||||
|
||||
/* t7 = B - x3 */
|
||||
vli_mod_sub(t7, x1, x2, curve_prime, ndigits);
|
||||
/* t4 = (y2 - y1)*(B - x3) */
|
||||
vli_mod_mult_fast(y2, y2, t7, curve_prime, ndigits);
|
||||
vli_mod_mult_fast(y2, y2, t7, curve);
|
||||
/* t4 = y3 */
|
||||
vli_mod_sub(y2, y2, y1, curve_prime, ndigits);
|
||||
|
||||
/* t7 = (y2 + y1)^2 = F */
|
||||
vli_mod_square_fast(t7, t5, curve_prime, ndigits);
|
||||
vli_mod_square_fast(t7, t5, curve);
|
||||
/* t7 = x3' */
|
||||
vli_mod_sub(t7, t7, t6, curve_prime, ndigits);
|
||||
/* t6 = x3' - B */
|
||||
vli_mod_sub(t6, t7, x1, curve_prime, ndigits);
|
||||
/* t6 = (y2 + y1)*(x3' - B) */
|
||||
vli_mod_mult_fast(t6, t6, t5, curve_prime, ndigits);
|
||||
vli_mod_mult_fast(t6, t6, t5, curve);
|
||||
/* t2 = y3' */
|
||||
vli_mod_sub(y1, t6, y1, curve_prime, ndigits);
|
||||
|
||||
@ -1165,41 +1288,37 @@ static void ecc_point_mult(struct ecc_point *result,
|
||||
vli_set(rx[1], point->x, ndigits);
|
||||
vli_set(ry[1], point->y, ndigits);
|
||||
|
||||
xycz_initial_double(rx[1], ry[1], rx[0], ry[0], initial_z, curve_prime,
|
||||
ndigits);
|
||||
xycz_initial_double(rx[1], ry[1], rx[0], ry[0], initial_z, curve);
|
||||
|
||||
for (i = num_bits - 2; i > 0; i--) {
|
||||
nb = !vli_test_bit(scalar, i);
|
||||
xycz_add_c(rx[1 - nb], ry[1 - nb], rx[nb], ry[nb], curve_prime,
|
||||
ndigits);
|
||||
xycz_add(rx[nb], ry[nb], rx[1 - nb], ry[1 - nb], curve_prime,
|
||||
ndigits);
|
||||
xycz_add_c(rx[1 - nb], ry[1 - nb], rx[nb], ry[nb], curve);
|
||||
xycz_add(rx[nb], ry[nb], rx[1 - nb], ry[1 - nb], curve);
|
||||
}
|
||||
|
||||
nb = !vli_test_bit(scalar, 0);
|
||||
xycz_add_c(rx[1 - nb], ry[1 - nb], rx[nb], ry[nb], curve_prime,
|
||||
ndigits);
|
||||
xycz_add_c(rx[1 - nb], ry[1 - nb], rx[nb], ry[nb], curve);
|
||||
|
||||
/* Find final 1/Z value. */
|
||||
/* X1 - X0 */
|
||||
vli_mod_sub(z, rx[1], rx[0], curve_prime, ndigits);
|
||||
/* Yb * (X1 - X0) */
|
||||
vli_mod_mult_fast(z, z, ry[1 - nb], curve_prime, ndigits);
|
||||
vli_mod_mult_fast(z, z, ry[1 - nb], curve);
|
||||
/* xP * Yb * (X1 - X0) */
|
||||
vli_mod_mult_fast(z, z, point->x, curve_prime, ndigits);
|
||||
vli_mod_mult_fast(z, z, point->x, curve);
|
||||
|
||||
/* 1 / (xP * Yb * (X1 - X0)) */
|
||||
vli_mod_inv(z, z, curve_prime, point->ndigits);
|
||||
|
||||
/* yP / (xP * Yb * (X1 - X0)) */
|
||||
vli_mod_mult_fast(z, z, point->y, curve_prime, ndigits);
|
||||
vli_mod_mult_fast(z, z, point->y, curve);
|
||||
/* Xb * yP / (xP * Yb * (X1 - X0)) */
|
||||
vli_mod_mult_fast(z, z, rx[1 - nb], curve_prime, ndigits);
|
||||
vli_mod_mult_fast(z, z, rx[1 - nb], curve);
|
||||
/* End 1/Z calculation */
|
||||
|
||||
xycz_add(rx[nb], ry[nb], rx[1 - nb], ry[1 - nb], curve_prime, ndigits);
|
||||
xycz_add(rx[nb], ry[nb], rx[1 - nb], ry[1 - nb], curve);
|
||||
|
||||
apply_z(rx[0], ry[0], z, curve_prime, ndigits);
|
||||
apply_z(rx[0], ry[0], z, curve);
|
||||
|
||||
vli_set(result->x, rx[0], ndigits);
|
||||
vli_set(result->y, ry[0], ndigits);
|
||||
@ -1220,9 +1339,9 @@ static void ecc_point_add(const struct ecc_point *result,
|
||||
vli_mod_sub(z, result->x, p->x, curve->p, ndigits);
|
||||
vli_set(px, p->x, ndigits);
|
||||
vli_set(py, p->y, ndigits);
|
||||
xycz_add(px, py, result->x, result->y, curve->p, ndigits);
|
||||
xycz_add(px, py, result->x, result->y, curve);
|
||||
vli_mod_inv(z, z, curve->p, ndigits);
|
||||
apply_z(result->x, result->y, z, curve->p, ndigits);
|
||||
apply_z(result->x, result->y, z, curve);
|
||||
}
|
||||
|
||||
/* Computes R = u1P + u2Q mod p using Shamir's trick.
|
||||
@ -1251,8 +1370,7 @@ void ecc_point_mult_shamir(const struct ecc_point *result,
|
||||
points[2] = q;
|
||||
points[3] = ∑
|
||||
|
||||
num_bits = max(vli_num_bits(u1, ndigits),
|
||||
vli_num_bits(u2, ndigits));
|
||||
num_bits = max(vli_num_bits(u1, ndigits), vli_num_bits(u2, ndigits));
|
||||
i = num_bits - 1;
|
||||
idx = (!!vli_test_bit(u1, i)) | ((!!vli_test_bit(u2, i)) << 1);
|
||||
point = points[idx];
|
||||
@ -1263,7 +1381,7 @@ void ecc_point_mult_shamir(const struct ecc_point *result,
|
||||
z[0] = 1;
|
||||
|
||||
for (--i; i >= 0; i--) {
|
||||
ecc_point_double_jacobian(rx, ry, z, curve->p, ndigits);
|
||||
ecc_point_double_jacobian(rx, ry, z, curve);
|
||||
idx = (!!vli_test_bit(u1, i)) | ((!!vli_test_bit(u2, i)) << 1);
|
||||
point = points[idx];
|
||||
if (point) {
|
||||
@ -1273,14 +1391,14 @@ void ecc_point_mult_shamir(const struct ecc_point *result,
|
||||
|
||||
vli_set(tx, point->x, ndigits);
|
||||
vli_set(ty, point->y, ndigits);
|
||||
apply_z(tx, ty, z, curve->p, ndigits);
|
||||
apply_z(tx, ty, z, curve);
|
||||
vli_mod_sub(tz, rx, tx, curve->p, ndigits);
|
||||
xycz_add(tx, ty, rx, ry, curve->p, ndigits);
|
||||
vli_mod_mult_fast(z, z, tz, curve->p, ndigits);
|
||||
xycz_add(tx, ty, rx, ry, curve);
|
||||
vli_mod_mult_fast(z, z, tz, curve);
|
||||
}
|
||||
}
|
||||
vli_mod_inv(z, z, curve->p, ndigits);
|
||||
apply_z(rx, ry, z, curve->p, ndigits);
|
||||
apply_z(rx, ry, z, curve);
|
||||
}
|
||||
EXPORT_SYMBOL(ecc_point_mult_shamir);
|
||||
|
||||
@ -1434,10 +1552,10 @@ int ecc_is_pubkey_valid_partial(const struct ecc_curve *curve,
|
||||
return -EINVAL;
|
||||
|
||||
/* Check 3: Verify that y^2 == (x^3 + a·x + b) mod p */
|
||||
vli_mod_square_fast(yy, pk->y, curve->p, pk->ndigits); /* y^2 */
|
||||
vli_mod_square_fast(xxx, pk->x, curve->p, pk->ndigits); /* x^2 */
|
||||
vli_mod_mult_fast(xxx, xxx, pk->x, curve->p, pk->ndigits); /* x^3 */
|
||||
vli_mod_mult_fast(w, curve->a, pk->x, curve->p, pk->ndigits); /* a·x */
|
||||
vli_mod_square_fast(yy, pk->y, curve); /* y^2 */
|
||||
vli_mod_square_fast(xxx, pk->x, curve); /* x^2 */
|
||||
vli_mod_mult_fast(xxx, xxx, pk->x, curve); /* x^3 */
|
||||
vli_mod_mult_fast(w, curve->a, pk->x, curve); /* a·x */
|
||||
vli_mod_add(w, w, curve->b, curve->p, pk->ndigits); /* a·x + b */
|
||||
vli_mod_add(w, w, xxx, curve->p, pk->ndigits); /* x^3 + a·x + b */
|
||||
if (vli_cmp(yy, w, pk->ndigits) != 0) /* Equation */
|
||||
|
||||
@ -29,7 +29,8 @@
|
||||
/* One digit is u64 qword. */
|
||||
#define ECC_CURVE_NIST_P192_DIGITS 3
|
||||
#define ECC_CURVE_NIST_P256_DIGITS 4
|
||||
#define ECC_MAX_DIGITS (512 / 64)
|
||||
#define ECC_CURVE_NIST_P384_DIGITS 6
|
||||
#define ECC_MAX_DIGITS (512 / 64) /* due to ecrdsa */
|
||||
|
||||
#define ECC_DIGITS_TO_BYTES_SHIFT 3
|
||||
|
||||
|
||||
Loading…
Reference in New Issue
Block a user