resolve conflicts

1 files changed, 46 insertions, 19 deletions

diff --git a/lib/libcrypto/dh/dh_key.c b/lib/libcrypto/dh/dh_key.c
index 648766a6ec4..e3641ec4686 100644
--- a/lib/libcrypto/dh/dh_key.c
+++ b/lib/libcrypto/dh/dh_key.c
@@ -105,7 +105,7 @@ static int generate_key(DH *dh)
 	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();
@@ -128,21 +128,37 @@ static int generate_key(DH *dh)
 	else
 		pub_key=dh->pub_key;
 
-	if ((dh->method_mont_p == NULL) && (dh->flags & DH_FLAG_CACHE_MONT_P))
+
+	if (dh->flags & DH_FLAG_CACHE_MONT_P)
 		{
-		if ((dh->method_mont_p=(char *)BN_MONT_CTX_new()) != NULL)
-			if (!BN_MONT_CTX_set((BN_MONT_CTX *)dh->method_mont_p,
-				dh->p,ctx)) goto err;
+		mont = BN_MONT_CTX_set_locked(
+				(BN_MONT_CTX **)&dh->method_mont_p,
+				CRYPTO_LOCK_DH, dh->p, ctx);
+		if (!mont)
+			goto err;
 		}
-	mont=(BN_MONT_CTX *)dh->method_mont_p;
 
 	if (generate_new_key)
 		{
 		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;
@@ -160,7 +176,7 @@ err:
 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;
 	int check_result;
@@ -175,15 +191,20 @@ static int compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
 		DHerr(DH_F_DH_COMPUTE_KEY,DH_R_NO_PRIVATE_VALUE);
 		goto err;
 		}
-	if ((dh->method_mont_p == NULL) && (dh->flags & DH_FLAG_CACHE_MONT_P))
+
+	if (dh->flags & DH_FLAG_CACHE_MONT_P)
 		{
-		if ((dh->method_mont_p=(char *)BN_MONT_CTX_new()) != NULL)
-			if (!BN_MONT_CTX_set((BN_MONT_CTX *)dh->method_mont_p,
-				dh->p,ctx)) goto err;
+		mont = BN_MONT_CTX_set_locked(
+				(BN_MONT_CTX **)&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;
 		}
-
-	mont=(BN_MONT_CTX *)dh->method_mont_p;
-
 	if (!DH_check_pub_key(dh, pub_key, &check_result) || check_result)
 		{
 		DHerr(DH_F_DH_COMPUTE_KEY,DH_R_INVALID_PUBKEY);
@@ -197,8 +218,11 @@ static int compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
 
 	ret=BN_bn2bin(tmp,key);
 err:
-	BN_CTX_end(ctx);
-	BN_CTX_free(ctx);
+	if (ctx != NULL)
+		{
+		BN_CTX_end(ctx);
+		BN_CTX_free(ctx);
+		}
 	return(ret);
 	}
 
@@ -207,7 +231,10 @@ static int dh_bn_mod_exp(const DH *dh, BIGNUM *r,
 			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);