/*
- * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
int i, bits, ret = 0;
BIGNUM *v, *rr;
- if (BN_get_flags(p, BN_FLG_CONSTTIME) != 0) {
+ if (BN_get_flags(p, BN_FLG_CONSTTIME) != 0
+ || BN_get_flags(a, BN_FLG_CONSTTIME) != 0) {
/* BN_FLG_CONSTTIME only supported by BN_mod_exp_mont() */
BNerr(BN_F_BN_EXP, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
- return -1;
+ return 0;
}
BN_CTX_start(ctx);
- if ((r == a) || (r == p))
- rr = BN_CTX_get(ctx);
- else
- rr = r;
+ rr = ((r == a) || (r == p)) ? BN_CTX_get(ctx) : r;
v = BN_CTX_get(ctx);
if (rr == NULL || v == NULL)
goto err;
goto err;
}
}
- if (r != rr)
- BN_copy(r, rr);
+ if (r != rr && BN_copy(r, rr) == NULL)
+ goto err;
+
ret = 1;
err:
BN_CTX_end(ctx);
bn_check_top(r);
- return (ret);
+ return ret;
}
int BN_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, const BIGNUM *m,
#define RECP_MUL_MOD
#ifdef MONT_MUL_MOD
- /*
- * I have finally been able to take out this pre-condition of the top bit
- * being set. It was caused by an error in BN_div with negatives. There
- * was also another problem when for a^b%m a >= m. eay 07-May-97
- */
- /* if ((m->d[m->top-1]&BN_TBIT) && BN_is_odd(m)) */
-
if (BN_is_odd(m)) {
# ifdef MONT_EXP_WORD
if (a->top == 1 && !a->neg
- && (BN_get_flags(p, BN_FLG_CONSTTIME) == 0)) {
+ && (BN_get_flags(p, BN_FLG_CONSTTIME) == 0)
+ && (BN_get_flags(a, BN_FLG_CONSTTIME) == 0)
+ && (BN_get_flags(m, BN_FLG_CONSTTIME) == 0)) {
BN_ULONG A = a->d[0];
ret = BN_mod_exp_mont_word(r, A, p, m, ctx, NULL);
} else
#endif
bn_check_top(r);
- return (ret);
+ return ret;
}
int BN_mod_exp_recp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
BIGNUM *val[TABLE_SIZE];
BN_RECP_CTX recp;
- if (BN_get_flags(p, BN_FLG_CONSTTIME) != 0) {
+ if (BN_get_flags(p, BN_FLG_CONSTTIME) != 0
+ || BN_get_flags(a, BN_FLG_CONSTTIME) != 0
+ || BN_get_flags(m, BN_FLG_CONSTTIME) != 0) {
/* BN_FLG_CONSTTIME only supported by BN_mod_exp_mont() */
BNerr(BN_F_BN_MOD_EXP_RECP, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
- return -1;
+ return 0;
}
bits = BN_num_bits(p);
BN_CTX_start(ctx);
aa = BN_CTX_get(ctx);
val[0] = BN_CTX_get(ctx);
- if (!aa || !val[0])
+ if (val[0] == NULL)
goto err;
BN_RECP_CTX_init(&recp);
BN_CTX_end(ctx);
BN_RECP_CTX_free(&recp);
bn_check_top(r);
- return (ret);
+ return ret;
}
int BN_mod_exp_mont(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p,
BIGNUM *val[TABLE_SIZE];
BN_MONT_CTX *mont = NULL;
- if (BN_get_flags(p, BN_FLG_CONSTTIME) != 0) {
+ if (BN_get_flags(p, BN_FLG_CONSTTIME) != 0
+ || BN_get_flags(a, BN_FLG_CONSTTIME) != 0
+ || BN_get_flags(m, BN_FLG_CONSTTIME) != 0) {
return BN_mod_exp_mont_consttime(rr, a, p, m, ctx, in_mont);
}
if (!BN_is_odd(m)) {
BNerr(BN_F_BN_MOD_EXP_MONT, BN_R_CALLED_WITH_EVEN_MODULUS);
- return (0);
+ return 0;
}
bits = BN_num_bits(p);
if (bits == 0) {
d = BN_CTX_get(ctx);
r = BN_CTX_get(ctx);
val[0] = BN_CTX_get(ctx);
- if (!d || !r || !val[0])
+ if (val[0] == NULL)
goto err;
/*
BN_MONT_CTX_free(mont);
BN_CTX_end(ctx);
bn_check_top(rr);
- return (ret);
+ return ret;
}
#if defined(SPARC_T4_MONT)
if (!BN_is_odd(m)) {
BNerr(BN_F_BN_MOD_EXP_MONT_CONSTTIME, BN_R_CALLED_WITH_EVEN_MODULUS);
- return (0);
+ return 0;
}
top = m->top;
- bits = BN_num_bits(p);
+ /*
+ * Use all bits stored in |p|, rather than |BN_num_bits|, so we do not leak
+ * whether the top bits are zero.
+ */
+ bits = p->top * BN_BITS2;
if (bits == 0) {
/* x**0 mod 1 is still zero. */
if (BN_is_one(m)) {
}
#ifdef RSAZ_ENABLED
- /*
- * If the size of the operands allow it, perform the optimized
- * RSAZ exponentiation. For further information see
- * crypto/bn/rsaz_exp.c and accompanying assembly modules.
- */
- if ((16 == a->top) && (16 == p->top) && (BN_num_bits(m) == 1024)
- && rsaz_avx2_eligible()) {
- if (NULL == bn_wexpand(rr, 16))
+ if (!a->neg) {
+ /*
+ * If the size of the operands allow it, perform the optimized
+ * RSAZ exponentiation. For further information see
+ * crypto/bn/rsaz_exp.c and accompanying assembly modules.
+ */
+ if ((16 == a->top) && (16 == p->top) && (BN_num_bits(m) == 1024)
+ && rsaz_avx2_eligible()) {
+ if (NULL == bn_wexpand(rr, 16))
+ goto err;
+ RSAZ_1024_mod_exp_avx2(rr->d, a->d, p->d, m->d, mont->RR.d,
+ mont->n0[0]);
+ rr->top = 16;
+ rr->neg = 0;
+ bn_correct_top(rr);
+ ret = 1;
goto err;
- RSAZ_1024_mod_exp_avx2(rr->d, a->d, p->d, m->d, mont->RR.d,
- mont->n0[0]);
- rr->top = 16;
- rr->neg = 0;
- bn_correct_top(rr);
- ret = 1;
- goto err;
- } else if ((8 == a->top) && (8 == p->top) && (BN_num_bits(m) == 512)) {
- if (NULL == bn_wexpand(rr, 8))
+ } else if ((8 == a->top) && (8 == p->top) && (BN_num_bits(m) == 512)) {
+ if (NULL == bn_wexpand(rr, 8))
+ goto err;
+ RSAZ_512_mod_exp(rr->d, a->d, p->d, m->d, mont->n0[0], mont->RR.d);
+ rr->top = 8;
+ rr->neg = 0;
+ bn_correct_top(rr);
+ ret = 1;
goto err;
- RSAZ_512_mod_exp(rr->d, a->d, p->d, m->d, mont->n0[0], mont->RR.d);
- rr->top = 8;
- rr->neg = 0;
- bn_correct_top(rr);
- ret = 1;
- goto err;
+ }
}
#endif
/* prepare a^1 in Montgomery domain */
if (a->neg || BN_ucmp(a, m) >= 0) {
- if (!BN_mod(&am, a, m, ctx))
+ if (!BN_nnmod(&am, a, m, ctx))
goto err;
if (!BN_to_montgomery(&am, &am, mont, ctx))
goto err;
OPENSSL_free(powerbufFree);
}
BN_CTX_end(ctx);
- return (ret);
+ return ret;
}
int BN_mod_exp_mont_word(BIGNUM *rr, BN_ULONG a, const BIGNUM *p,
int b, bits, ret = 0;
int r_is_one;
BN_ULONG w, next_w;
- BIGNUM *d, *r, *t;
+ BIGNUM *r, *t;
BIGNUM *swap_tmp;
#define BN_MOD_MUL_WORD(r, w, m) \
(BN_mul_word(r, (w)) && \
#define BN_TO_MONTGOMERY_WORD(r, w, mont) \
(BN_set_word(r, (w)) && BN_to_montgomery(r, r, (mont), ctx))
- if (BN_get_flags(p, BN_FLG_CONSTTIME) != 0) {
+ if (BN_get_flags(p, BN_FLG_CONSTTIME) != 0
+ || BN_get_flags(m, BN_FLG_CONSTTIME) != 0) {
/* BN_FLG_CONSTTIME only supported by BN_mod_exp_mont() */
BNerr(BN_F_BN_MOD_EXP_MONT_WORD, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
- return -1;
+ return 0;
}
bn_check_top(p);
if (!BN_is_odd(m)) {
BNerr(BN_F_BN_MOD_EXP_MONT_WORD, BN_R_CALLED_WITH_EVEN_MODULUS);
- return (0);
+ return 0;
}
if (m->top == 1)
a %= m->d[0]; /* make sure that 'a' is reduced */
}
BN_CTX_start(ctx);
- d = BN_CTX_get(ctx);
r = BN_CTX_get(ctx);
t = BN_CTX_get(ctx);
- if (d == NULL || r == NULL || t == NULL)
+ if (t == NULL)
goto err;
if (in_mont != NULL)
BN_MONT_CTX_free(mont);
BN_CTX_end(ctx);
bn_check_top(rr);
- return (ret);
+ return ret;
}
/* The old fallback, simple version :-) */
/* Table of variables obtained from 'ctx' */
BIGNUM *val[TABLE_SIZE];
- if (BN_get_flags(p, BN_FLG_CONSTTIME) != 0) {
+ if (BN_get_flags(p, BN_FLG_CONSTTIME) != 0
+ || BN_get_flags(a, BN_FLG_CONSTTIME) != 0
+ || BN_get_flags(m, BN_FLG_CONSTTIME) != 0) {
/* BN_FLG_CONSTTIME only supported by BN_mod_exp_mont() */
BNerr(BN_F_BN_MOD_EXP_SIMPLE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
- return -1;
+ return 0;
}
bits = BN_num_bits(p);
- if (bits == 0) {
+ if (bits == 0) {
/* x**0 mod 1 is still zero. */
if (BN_is_one(m)) {
ret = 1;
BN_CTX_start(ctx);
d = BN_CTX_get(ctx);
val[0] = BN_CTX_get(ctx);
- if (!d || !val[0])
+ if (val[0] == NULL)
goto err;
if (!BN_nnmod(val[0], a, m, ctx))
err:
BN_CTX_end(ctx);
bn_check_top(r);
- return (ret);
+ return ret;
}