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karel-mkarel-m
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fix LTC_MECC_FP (unfinished)
1 parent c9376c2 commit 72c7eae

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2 files changed

+56
-68
lines changed

2 files changed

+56
-68
lines changed

‎src/headers/tomcrypt_private.h

+2-2
Original file line numberDiff line numberDiff line change
@@ -219,13 +219,13 @@ int ltc_ecc_projective_add_point(const ecc_point *P, const ecc_point *Q, ecc_poi
219219

220220
#if defined(LTC_MECC_FP)
221221
/* optimized point multiplication using fixed point cache (HAC algorithm 14.117) */
222-
int ltc_ecc_fp_mulmod(void *k, ecc_point *G, ecc_point *R, void *a, void *modulus, int map);
222+
int ltc_ecc_fp_mulmod(void *k, const ecc_point *G, ecc_point *R, void *ma, void *modulus, int map);
223223

224224
/* functions for saving/loading/freeing/adding to fixed point cache */
225225
int ltc_ecc_fp_save_state(unsigned char **out, unsigned long *outlen);
226226
int ltc_ecc_fp_restore_state(unsigned char *in, unsigned long inlen);
227227
void ltc_ecc_fp_free(void);
228-
int ltc_ecc_fp_add_point(ecc_point *g, void *modulus, int lock);
228+
int ltc_ecc_fp_add_point(const ecc_point *g, void *ma, void *modulus, int lock);
229229

230230
/* lock/unlock all points currently in fixed point cache */
231231
void ltc_ecc_fp_tablelock(int lock);

‎src/math/fp/ltc_ecc_fp_mulmod.c

+54-66
Original file line numberDiff line numberDiff line change
@@ -571,6 +571,30 @@ static const struct {
571571
#endif
572572
};
573573

574+
static int _find_order_for_modulus(void *modulus, void **order)
575+
{
576+
void *bn;
577+
int err;
578+
const ltc_ecc_curve *curve;
579+
580+
if ((err = mp_init(&bn)) != CRYPT_OK) return err;;
581+
for (curve = ltc_ecc_curves; curve->prime != NULL; curve++) {
582+
if (mp_read_radix(bn, curve->prime, 16) != CRYPT_OK) continue;
583+
if (mp_cmp(bn, modulus) != LTC_MP_EQ) continue;
584+
break; /* found */
585+
}
586+
mp_clear(bn);
587+
if (curve->order == NULL) return CRYPT_ERROR;
588+
if ((err = mp_init(order)) != CRYPT_OK) {
589+
return err;
590+
}
591+
if ((err = mp_read_radix(*order, curve->order, 16)) != CRYPT_OK) {
592+
mp_clear(order);
593+
return err;
594+
}
595+
return CRYPT_OK;
596+
}
597+
574598
/* find a hole and free as required, return -1 if no hole found */
575599
static int _find_hole(void)
576600
{
@@ -608,7 +632,7 @@ static int _find_hole(void)
608632
}
609633

610634
/* determine if a base is already in the cache and if so, where */
611-
static int _find_base(ecc_point *g)
635+
static int _find_base(const ecc_point *g)
612636
{
613637
int x;
614638
for (x = 0; x < FP_ENTRIES; x++) {
@@ -626,7 +650,7 @@ static int _find_base(ecc_point *g)
626650
}
627651

628652
/* add a new base to the cache */
629-
static int _add_entry(int idx, ecc_point *g)
653+
static int _add_entry(int idx, const ecc_point *g)
630654
{
631655
unsigned x, y;
632656

@@ -668,7 +692,7 @@ static int _add_entry(int idx, ecc_point *g)
668692
* The algorithm builds patterns in increasing bit order by first making all
669693
* single bit input patterns, then all two bit input patterns and so on
670694
*/
671-
static int _build_lut(int idx, void *a, void *modulus, void *mp, void *mu)
695+
static int _build_lut(int idx, void *ma, void *modulus, void *mp, void *mu)
672696
{
673697
unsigned x, y, err, bitlen, lut_gap;
674698
void *tmp;
@@ -707,7 +731,7 @@ static int _build_lut(int idx, void *a, void *modulus, void *mp, void *mu)
707731

708732
/* now double it bitlen/FP_LUT times */
709733
for (y = 0; y < lut_gap; y++) {
710-
if ((err = ltc_mp.ecc_ptdbl(fp_cache[idx].LUT[1<<x], fp_cache[idx].LUT[1<<x], a, modulus, mp)) != CRYPT_OK) {
734+
if ((err = ltc_mp.ecc_ptdbl(fp_cache[idx].LUT[1<<x], fp_cache[idx].LUT[1<<x], ma, modulus, mp)) != CRYPT_OK) {
711735
goto ERR;
712736
}
713737
}
@@ -720,7 +744,7 @@ static int _build_lut(int idx, void *a, void *modulus, void *mp, void *mu)
720744

721745
/* perform the add */
722746
if ((err = ltc_mp.ecc_ptadd(fp_cache[idx].LUT[lut_orders[y].terma], fp_cache[idx].LUT[lut_orders[y].termb],
723-
fp_cache[idx].LUT[y], a, modulus, mp)) != CRYPT_OK) {
747+
fp_cache[idx].LUT[y], ma, modulus, mp)) != CRYPT_OK) {
724748
goto ERR;
725749
}
726750
}
@@ -747,9 +771,8 @@ static int _build_lut(int idx, void *a, void *modulus, void *mp, void *mu)
747771
/* fix y */
748772
if ((err = mp_mulmod(fp_cache[idx].LUT[x]->y, tmp, modulus, fp_cache[idx].LUT[x]->y)) != CRYPT_OK) { goto ERR; }
749773

750-
/* free z */
751-
mp_clear(fp_cache[idx].LUT[x]->z);
752-
fp_cache[idx].LUT[x]->z = NULL;
774+
/* fix z */
775+
if ((err = mp_set(fp_cache[idx].LUT[x]->z, 1)) != CRYPT_OK) { goto ERR; }
753776
}
754777
mp_clear(tmp);
755778

@@ -775,7 +798,7 @@ static int _build_lut(int idx, void *a, void *modulus, void *mp, void *mu)
775798
}
776799

777800
/* perform a fixed point ECC mulmod */
778-
static int _accel_fp_mul(int idx, void *k, ecc_point *R, void *a, void *modulus, void *mp, int map)
801+
static int _accel_fp_mul(int idx, void *k, ecc_point *R, void *ma, void *modulus, void *mp, int map)
779802
{
780803
unsigned char kb[128];
781804
int x;
@@ -785,19 +808,7 @@ static int _accel_fp_mul(int idx, void *k, ecc_point *R, void *a, void *modulus,
785808
/* if it's smaller than modulus we fine */
786809
if (mp_unsigned_bin_size(k) > mp_unsigned_bin_size(modulus)) {
787810
/* find order */
788-
y = mp_unsigned_bin_size(modulus);
789-
for (x = 0; ltc_ecc_sets[x].size; x++) {
790-
if (y <= (unsigned)ltc_ecc_sets[x].size) break;
791-
}
792-
793-
/* back off if we are on the 521 bit curve */
794-
if (y == 66) --x;
795-
796-
if ((err = mp_init(&order)) != CRYPT_OK) {
797-
return err;
798-
}
799-
if ((err = mp_read_radix(order, ltc_ecc_sets[x].order, 16)) != CRYPT_OK) {
800-
mp_clear(&order);
811+
if ((err = _find_order_for_modulus(modulus, &order)) != CRYPT_OK) {
801812
return err;
802813
}
803814

@@ -868,14 +879,14 @@ static int _accel_fp_mul(int idx, void *k, ecc_point *R, void *a, void *modulus,
868879

869880
/* double if not first */
870881
if (!first) {
871-
if ((err = ltc_mp.ecc_ptdbl(R, R, a, modulus, mp)) != CRYPT_OK) {
882+
if ((err = ltc_mp.ecc_ptdbl(R, R, ma, modulus, mp)) != CRYPT_OK) {
872883
return err;
873884
}
874885
}
875886

876887
/* add if not first, otherwise copy */
877888
if (!first && z) {
878-
if ((err = ltc_mp.ecc_ptadd(R, fp_cache[idx].LUT[z], R, a, modulus, mp)) != CRYPT_OK) {
889+
if ((err = ltc_mp.ecc_ptadd(R, fp_cache[idx].LUT[z], R, ma, modulus, mp)) != CRYPT_OK) {
879890
return err;
880891
}
881892
} else if (z) {
@@ -910,19 +921,7 @@ static int _accel_fp_mul2add(int idx1, int idx2,
910921
/* if it's smaller than modulus we fine */
911922
if (mp_unsigned_bin_size(kA) > mp_unsigned_bin_size(modulus)) {
912923
/* find order */
913-
y = mp_unsigned_bin_size(modulus);
914-
for (x = 0; ltc_ecc_sets[x].size; x++) {
915-
if (y <= (unsigned)ltc_ecc_sets[x].size) break;
916-
}
917-
918-
/* back off if we are on the 521 bit curve */
919-
if (y == 66) --x;
920-
921-
if ((err = mp_init(&order)) != CRYPT_OK) {
922-
return err;
923-
}
924-
if ((err = mp_read_radix(order, ltc_ecc_sets[x].order, 16)) != CRYPT_OK) {
925-
mp_clear(&order);
924+
if ((err = _find_order_for_modulus(modulus, &order)) != CRYPT_OK) {
926925
return err;
927926
}
928927

@@ -948,19 +947,7 @@ static int _accel_fp_mul2add(int idx1, int idx2,
948947
/* if it's smaller than modulus we fine */
949948
if (mp_unsigned_bin_size(kB) > mp_unsigned_bin_size(modulus)) {
950949
/* find order */
951-
y = mp_unsigned_bin_size(modulus);
952-
for (x = 0; ltc_ecc_sets[x].size; x++) {
953-
if (y <= (unsigned)ltc_ecc_sets[x].size) break;
954-
}
955-
956-
/* back off if we are on the 521 bit curve */
957-
if (y == 66) --x;
958-
959-
if ((err = mp_init(&order)) != CRYPT_OK) {
960-
return err;
961-
}
962-
if ((err = mp_read_radix(order, ltc_ecc_sets[x].order, 16)) != CRYPT_OK) {
963-
mp_clear(&order);
950+
if ((err = _find_order_for_modulus(modulus, &order)) != CRYPT_OK) {
964951
return err;
965952
}
966953

@@ -1105,14 +1092,15 @@ static int _accel_fp_mul2add(int idx1, int idx2,
11051092
@param B Second point to multiply
11061093
@param kB What to multiple B by
11071094
@param C [out] Destination point (can overlap with A or B)
1095+
@param ma ECC curve parameter a in montgomery form
11081096
@param modulus Modulus for curve
11091097
@return CRYPT_OK on success
11101098
*/
1111-
int ltc_ecc_fp_mul2add(ecc_point *A, void *kA,
1112-
ecc_point *B, void *kB,
1113-
ecc_point *C,
1114-
void *a,
1115-
void *modulus)
1099+
int ltc_ecc_fp_mul2add(const ecc_point *A, void *kA,
1100+
const ecc_point *B, void *kB,
1101+
ecc_point *C,
1102+
void *ma,
1103+
void *modulus)
11161104
{
11171105
int idx1, idx2, err;
11181106
void *mp, *mu;
@@ -1168,7 +1156,7 @@ int ltc_ecc_fp_mul2add(ecc_point *A, void *kA,
11681156
}
11691157

11701158
/* build the LUT */
1171-
if ((err = _build_lut(idx1, a, modulus, mp, mu)) != CRYPT_OK) {
1159+
if ((err = _build_lut(idx1, ma, modulus, mp, mu)) != CRYPT_OK) {
11721160
goto LBL_ERR;;
11731161
}
11741162
}
@@ -1189,7 +1177,7 @@ int ltc_ecc_fp_mul2add(ecc_point *A, void *kA,
11891177
}
11901178

11911179
/* build the LUT */
1192-
if ((err = _build_lut(idx2, a, modulus, mp, mu)) != CRYPT_OK) {
1180+
if ((err = _build_lut(idx2, ma, modulus, mp, mu)) != CRYPT_OK) {
11931181
goto LBL_ERR;;
11941182
}
11951183
}
@@ -1200,9 +1188,9 @@ int ltc_ecc_fp_mul2add(ecc_point *A, void *kA,
12001188
/* compute mp */
12011189
if ((err = mp_montgomery_setup(modulus, &mp)) != CRYPT_OK) { goto LBL_ERR; }
12021190
}
1203-
err = _accel_fp_mul2add(idx1, idx2, kA, kB, C, a, modulus, mp);
1191+
err = _accel_fp_mul2add(idx1, idx2, kA, kB, C, ma, modulus, mp);
12041192
} else {
1205-
err = ltc_ecc_mul2add(A, kA, B, kB, C, a, modulus);
1193+
err = ltc_ecc_mul2add(A, kA, B, kB, C, ma, modulus);
12061194
}
12071195
LBL_ERR:
12081196
LTC_MUTEX_UNLOCK(&ltc_ecc_fp_lock);
@@ -1220,12 +1208,12 @@ int ltc_ecc_fp_mul2add(ecc_point *A, void *kA,
12201208
@param k The multiplicand
12211209
@param G Base point to multiply
12221210
@param R [out] Destination of product
1223-
@param a ECC curve parameter a
1211+
@param ma ECC curve parameter a in montgomery form
12241212
@param modulus The modulus for the curve
12251213
@param map [boolean] If non-zero maps the point back to affine co-ordinates, otherwise it's left in jacobian-montgomery form
12261214
@return CRYPT_OK if successful
12271215
*/
1228-
int ltc_ecc_fp_mulmod(void *k, ecc_point *G, ecc_point *R, void *a, void *modulus, int map)
1216+
int ltc_ecc_fp_mulmod(void *k, const ecc_point *G, ecc_point *R, void *ma, void *modulus, int map)
12291217
{
12301218
int idx, err;
12311219
void *mp, *mu;
@@ -1267,7 +1255,7 @@ int ltc_ecc_fp_mulmod(void *k, ecc_point *G, ecc_point *R, void *a, void *modulu
12671255
}
12681256

12691257
/* build the LUT */
1270-
if ((err = _build_lut(idx, a, modulus, mp, mu)) != CRYPT_OK) {
1258+
if ((err = _build_lut(idx, ma, modulus, mp, mu)) != CRYPT_OK) {
12711259
goto LBL_ERR;;
12721260
}
12731261
}
@@ -1277,9 +1265,9 @@ int ltc_ecc_fp_mulmod(void *k, ecc_point *G, ecc_point *R, void *a, void *modulu
12771265
/* compute mp */
12781266
if ((err = mp_montgomery_setup(modulus, &mp)) != CRYPT_OK) { goto LBL_ERR; }
12791267
}
1280-
err = _accel_fp_mul(idx, k, R, a, modulus, mp, map);
1268+
err = _accel_fp_mul(idx, k, R, ma, modulus, mp, map);
12811269
} else {
1282-
err = ltc_ecc_mulmod(k, G, R, a, modulus, map);
1270+
err = ltc_ecc_mulmod(k, G, R, ma, modulus, map);
12831271
}
12841272
LBL_ERR:
12851273
LTC_MUTEX_UNLOCK(&ltc_ecc_fp_lock);
@@ -1329,7 +1317,7 @@ void ltc_ecc_fp_free(void)
13291317
@return CRYPT_OK on success
13301318
*/
13311319
int
1332-
ltc_ecc_fp_add_point(ecc_point *g, void *modulus, int lock)
1320+
ltc_ecc_fp_add_point(const ecc_point *g, void *ma, void *modulus, int lock)
13331321
{
13341322
int idx;
13351323
int err;
@@ -1366,7 +1354,7 @@ ltc_ecc_fp_add_point(ecc_point *g, void *modulus, int lock)
13661354
}
13671355

13681356
/* build the LUT */
1369-
if ((err = _build_lut(idx, a, modulus, mp, mu)) != CRYPT_OK) {
1357+
if ((err = _build_lut(idx, ma, modulus, mp, mu)) != CRYPT_OK) {
13701358
goto LBL_ERR;
13711359
}
13721360
fp_cache[idx].lru_count = 2;

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