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Diffstat (limited to 'src/crypto/bn/exponentiation.c')
-rw-r--r--src/crypto/bn/exponentiation.c94
1 files changed, 40 insertions, 54 deletions
diff --git a/src/crypto/bn/exponentiation.c b/src/crypto/bn/exponentiation.c
index 9cefa62..c580248 100644
--- a/src/crypto/bn/exponentiation.c
+++ b/src/crypto/bn/exponentiation.c
@@ -613,17 +613,17 @@ int BN_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, const BIGNUM *m,
}
int BN_mod_exp_mont(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p,
- const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *in_mont) {
+ const BIGNUM *m, BN_CTX *ctx, const BN_MONT_CTX *mont) {
int i, j, bits, ret = 0, wstart, window;
int start = 1;
BIGNUM *d, *r;
const BIGNUM *aa;
/* Table of variables obtained from 'ctx' */
BIGNUM *val[TABLE_SIZE];
- BN_MONT_CTX *mont = NULL;
+ BN_MONT_CTX *new_mont = NULL;
if (BN_get_flags(p, BN_FLG_CONSTTIME) != 0) {
- return BN_mod_exp_mont_consttime(rr, a, p, m, ctx, in_mont);
+ return BN_mod_exp_mont_consttime(rr, a, p, m, ctx, mont);
}
if (!BN_is_odd(m)) {
@@ -644,18 +644,13 @@ int BN_mod_exp_mont(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p,
goto err;
}
- /* If this is not done, things will break in the montgomery part */
-
- if (in_mont != NULL) {
- mont = in_mont;
- } else {
- mont = BN_MONT_CTX_new();
- if (mont == NULL) {
- goto err;
- }
- if (!BN_MONT_CTX_set(mont, m, ctx)) {
+ /* Allocate a montgomery context if it was not supplied by the caller. */
+ if (mont == NULL) {
+ new_mont = BN_MONT_CTX_new();
+ if (new_mont == NULL || !BN_MONT_CTX_set(new_mont, m, ctx)) {
goto err;
}
+ mont = new_mont;
}
if (a->neg || BN_ucmp(a, m) >= 0) {
@@ -774,9 +769,7 @@ int BN_mod_exp_mont(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p,
ret = 1;
err:
- if (in_mont == NULL) {
- BN_MONT_CTX_free(mont);
- }
+ BN_MONT_CTX_free(new_mont);
BN_CTX_end(ctx);
return ret;
}
@@ -862,10 +855,10 @@ static int copy_from_prebuf(BIGNUM *b, int top, unsigned char *buf, int idx,
*/
int BN_mod_exp_mont_consttime(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p,
const BIGNUM *m, BN_CTX *ctx,
- BN_MONT_CTX *in_mont) {
+ const BN_MONT_CTX *mont) {
int i, bits, ret = 0, window, wvalue;
int top;
- BN_MONT_CTX *mont = NULL;
+ BN_MONT_CTX *new_mont = NULL;
int numPowers;
unsigned char *powerbufFree = NULL;
@@ -888,15 +881,13 @@ int BN_mod_exp_mont_consttime(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p,
BN_CTX_start(ctx);
- /* Allocate a montgomery context if it was not supplied by the caller.
- * If this is not done, things will break in the montgomery part. */
- if (in_mont != NULL) {
- mont = in_mont;
- } else {
- mont = BN_MONT_CTX_new();
- if (mont == NULL || !BN_MONT_CTX_set(mont, m, ctx)) {
+ /* Allocate a montgomery context if it was not supplied by the caller. */
+ if (mont == NULL) {
+ new_mont = BN_MONT_CTX_new();
+ if (new_mont == NULL || !BN_MONT_CTX_set(new_mont, m, ctx)) {
goto err;
}
+ mont = new_mont;
}
#ifdef RSAZ_ENABLED
@@ -1005,7 +996,7 @@ int BN_mod_exp_mont_consttime(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p,
/* Dedicated window==4 case improves 512-bit RSA sign by ~15%, but as
* 512-bit RSA is hardly relevant, we omit it to spare size... */
if (window == 5 && top > 1) {
- BN_ULONG *np = mont->N.d, *n0 = mont->n0, *np2;
+ const BN_ULONG *np = mont->N.d, *n0 = mont->n0, *np2;
/* BN_to_montgomery can contaminate words above .top
* [in BN_DEBUG[_DEBUG] build]... */
@@ -1019,9 +1010,11 @@ int BN_mod_exp_mont_consttime(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p,
if (top & 7) {
np2 = np;
} else {
- for (np2 = am.d + top, i = 0; i < top; i++) {
- np2[2 * i] = np[i];
+ BN_ULONG *np_double = am.d + top;
+ for (i = 0; i < top; i++) {
+ np_double[2 * i] = np[i];
}
+ np2 = np_double;
}
bn_scatter5(tmp.d, top, powerbuf, 0);
@@ -1186,10 +1179,9 @@ int BN_mod_exp_mont_consttime(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p,
goto err;
}
ret = 1;
+
err:
- if (in_mont == NULL) {
- BN_MONT_CTX_free(mont);
- }
+ BN_MONT_CTX_free(new_mont);
if (powerbuf != NULL) {
OPENSSL_cleanse(powerbuf, powerbufLen);
OPENSSL_free(powerbufFree);
@@ -1199,8 +1191,9 @@ err:
}
int BN_mod_exp_mont_word(BIGNUM *rr, BN_ULONG a, const BIGNUM *p,
- const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *in_mont) {
- BN_MONT_CTX *mont = NULL;
+ const BIGNUM *m, BN_CTX *ctx,
+ const BN_MONT_CTX *mont) {
+ BN_MONT_CTX *new_mont = NULL;
int b, bits, ret = 0;
int r_is_one;
BN_ULONG w, next_w;
@@ -1258,13 +1251,13 @@ int BN_mod_exp_mont_word(BIGNUM *rr, BN_ULONG a, const BIGNUM *p,
goto err;
}
- if (in_mont != NULL) {
- mont = in_mont;
- } else {
- mont = BN_MONT_CTX_new();
- if (mont == NULL || !BN_MONT_CTX_set(mont, m, ctx)) {
+ /* Allocate a montgomery context if it was not supplied by the caller. */
+ if (mont == NULL) {
+ new_mont = BN_MONT_CTX_new();
+ if (new_mont == NULL || !BN_MONT_CTX_set(new_mont, m, ctx)) {
goto err;
}
+ mont = new_mont;
}
r_is_one = 1; /* except for Montgomery factor */
@@ -1346,9 +1339,7 @@ int BN_mod_exp_mont_word(BIGNUM *rr, BN_ULONG a, const BIGNUM *p,
ret = 1;
err:
- if (in_mont == NULL) {
- BN_MONT_CTX_free(mont);
- }
+ BN_MONT_CTX_free(new_mont);
BN_CTX_end(ctx);
return ret;
}
@@ -1357,7 +1348,7 @@ err:
int BN_mod_exp2_mont(BIGNUM *rr, const BIGNUM *a1, const BIGNUM *p1,
const BIGNUM *a2, const BIGNUM *p2, const BIGNUM *m,
- BN_CTX *ctx, BN_MONT_CTX *in_mont) {
+ BN_CTX *ctx, const BN_MONT_CTX *mont) {
int i, j, bits, b, bits1, bits2, ret = 0, wpos1, wpos2, window1, window2,
wvalue1, wvalue2;
int r_is_one = 1;
@@ -1365,7 +1356,7 @@ int BN_mod_exp2_mont(BIGNUM *rr, const BIGNUM *a1, const BIGNUM *p1,
const BIGNUM *a_mod_m;
/* Tables of variables obtained from 'ctx' */
BIGNUM *val1[TABLE_SIZE], *val2[TABLE_SIZE];
- BN_MONT_CTX *mont = NULL;
+ BN_MONT_CTX *new_mont = NULL;
if (!(m->d[0] & 1)) {
OPENSSL_PUT_ERROR(BN, BN_R_CALLED_WITH_EVEN_MODULUS);
@@ -1389,16 +1380,13 @@ int BN_mod_exp2_mont(BIGNUM *rr, const BIGNUM *a1, const BIGNUM *p1,
goto err;
}
- if (in_mont != NULL) {
- mont = in_mont;
- } else {
- mont = BN_MONT_CTX_new();
- if (mont == NULL) {
- goto err;
- }
- if (!BN_MONT_CTX_set(mont, m, ctx)) {
+ /* Allocate a montgomery context if it was not supplied by the caller. */
+ if (mont == NULL) {
+ new_mont = BN_MONT_CTX_new();
+ if (new_mont == NULL || !BN_MONT_CTX_set(new_mont, m, ctx)) {
goto err;
}
+ mont = new_mont;
}
window1 = BN_window_bits_for_exponent_size(bits1);
@@ -1550,9 +1538,7 @@ int BN_mod_exp2_mont(BIGNUM *rr, const BIGNUM *a1, const BIGNUM *p1,
ret = 1;
err:
- if (in_mont == NULL) {
- BN_MONT_CTX_free(mont);
- }
+ BN_MONT_CTX_free(new_mont);
BN_CTX_end(ctx);
return ret;
}
generated by cgit v1.1 at 2024-05-18 18:19:25 +0000