int generate_new_key=0;
unsigned l;
BN_CTX *ctx;
- BN_MONT_CTX *mont;
+ BN_MONT_CTX *mont=NULL;
BIGNUM *pub_key=NULL,*priv_key=NULL;
ctx = BN_CTX_new();
if (dh->flags & DH_FLAG_CACHE_MONT_P)
{
- mont = BN_MONT_CTX_set_locked(
- (BN_MONT_CTX **)&dh->method_mont_p,
+ mont = BN_MONT_CTX_set_locked(&dh->method_mont_p,
CRYPTO_LOCK_DH, dh->p, ctx);
if (!mont)
goto err;
l = dh->length ? dh->length : BN_num_bits(dh->p)-1; /* secret exponent length */
if (!BN_rand(priv_key, l, 0, 0)) goto err;
}
- if (!dh->meth->bn_mod_exp(dh, pub_key, dh->g, priv_key,dh->p,ctx,mont))
- goto err;
+
+ {
+ BIGNUM local_prk;
+ BIGNUM *prk;
+
+ if ((dh->flags & DH_FLAG_NO_EXP_CONSTTIME) == 0)
+ {
+ BN_init(&local_prk);
+ prk = &local_prk;
+ BN_with_flags(prk, priv_key, BN_FLG_EXP_CONSTTIME);
+ }
+ else
+ prk = priv_key;
+
+ if (!dh->meth->bn_mod_exp(dh, pub_key, dh->g, prk, dh->p, ctx, mont)) goto err;
+ }
dh->pub_key=pub_key;
dh->priv_key=priv_key;
static int compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
{
BN_CTX *ctx;
- BN_MONT_CTX *mont;
+ BN_MONT_CTX *mont=NULL;
BIGNUM *tmp;
int ret= -1;
if (dh->flags & DH_FLAG_CACHE_MONT_P)
{
- mont = BN_MONT_CTX_set_locked(
- (BN_MONT_CTX **)&dh->method_mont_p,
+ mont = BN_MONT_CTX_set_locked(&dh->method_mont_p,
CRYPTO_LOCK_DH, dh->p, ctx);
+ if ((dh->flags & DH_FLAG_NO_EXP_CONSTTIME) == 0)
+ {
+ /* XXX */
+ BN_set_flags(dh->priv_key, BN_FLG_EXP_CONSTTIME);
+ }
if (!mont)
goto err;
}
const BIGNUM *m, BN_CTX *ctx,
BN_MONT_CTX *m_ctx)
{
- if (a->top == 1)
+ /* If a is only one word long and constant time is false, use the faster
+ * exponenentiation function.
+ */
+ if (a->top == 1 && ((dh->flags & DH_FLAG_NO_EXP_CONSTTIME) != 0))
{
BN_ULONG A = a->d[0];
return BN_mod_exp_mont_word(r,A,p,m,ctx,m_ctx);
static int dh_finish(DH *dh)
{
if(dh->method_mont_p)
- BN_MONT_CTX_free((BN_MONT_CTX *)dh->method_mont_p);
+ BN_MONT_CTX_free(dh->method_mont_p);
return(1);
}