X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=blobdiff_plain;f=crypto%2Fdh%2Fdh_key.c;h=39eefe387eab82b63a3e0a3c42097d4012771f44;hp=7a0ace72f0d5f85755c3534489c09b30495fa8dc;hb=a28a5d9c626c8b48d55f64ad77304578d1bd2a03;hpb=12c2fe8d53fd43559ea862c9babfc2abf3c65299

diff --git a/crypto/dh/dh_key.c b/crypto/dh/dh_key.c
index 7a0ace72f0..39eefe387e 100644
--- a/crypto/dh/dh_key.c
+++ b/crypto/dh/dh_key.c
@@ -61,7 +61,6 @@
 #include <openssl/bn.h>
 #include <openssl/rand.h>
 #include <openssl/dh.h>
-#include <openssl/engine.h>
 
 static int generate_key(DH *dh);
 static int compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh);
@@ -74,12 +73,12 @@ static int dh_finish(DH *dh);
 
 int DH_generate_key(DH *dh)
 	{
-	return ENGINE_get_DH(dh->engine)->generate_key(dh);
+	return dh->meth->generate_key(dh);
 	}
 
 int DH_compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
 	{
-	return ENGINE_get_DH(dh->engine)->compute_key(key, pub_key, dh);
+	return dh->meth->compute_key(key, pub_key, dh);
 	}
 
 static DH_METHOD dh_ossl = {
@@ -90,6 +89,7 @@ dh_bn_mod_exp,
 dh_init,
 dh_finish,
 0,
+NULL,
 NULL
 };
 
@@ -101,17 +101,20 @@ const DH_METHOD *DH_OpenSSL(void)
 static int generate_key(DH *dh)
 	{
 	int ok=0;
-	BN_CTX ctx;
-	BN_MONT_CTX *mont;
+	int generate_new_key=0;
+	unsigned l;
+	BN_CTX *ctx;
+	BN_MONT_CTX *mont=NULL;
 	BIGNUM *pub_key=NULL,*priv_key=NULL;
 
-	BN_CTX_init(&ctx);
+	ctx = BN_CTX_new();
+	if (ctx == NULL) goto err;
 
 	if (dh->priv_key == NULL)
 		{
 		priv_key=BN_new();
 		if (priv_key == NULL) goto err;
-		if (!BN_rand_range(priv_key, dh->p)) goto err;
+		generate_new_key=1;
 		}
 	else
 		priv_key=dh->priv_key;
@@ -124,66 +127,91 @@ 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(&dh->method_mont_p,
+				CRYPTO_LOCK_DH, dh->p, ctx);
+		if (!mont)
+			goto err;
 		}
-	mont=(BN_MONT_CTX *)dh->method_mont_p;
 
-	if (!ENGINE_get_DH(dh->engine)->bn_mod_exp(dh, pub_key, dh->g,
-				priv_key,dh->p,&ctx,mont))
-		goto err;
+	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;
+		}
+
+	{
+		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;
 	ok=1;
 err:
 	if (ok != 1)
-		DHerr(DH_F_DH_GENERATE_KEY,ERR_R_BN_LIB);
+		DHerr(DH_F_GENERATE_KEY,ERR_R_BN_LIB);
 
 	if ((pub_key != NULL)  && (dh->pub_key == NULL))  BN_free(pub_key);
 	if ((priv_key != NULL) && (dh->priv_key == NULL)) BN_free(priv_key);
-	BN_CTX_free(&ctx);
+	BN_CTX_free(ctx);
 	return(ok);
 	}
 
 static int compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
 	{
-	BN_CTX ctx;
-	BN_MONT_CTX *mont;
+	BN_CTX *ctx;
+	BN_MONT_CTX *mont=NULL;
 	BIGNUM *tmp;
 	int ret= -1;
 
-	BN_CTX_init(&ctx);
-	BN_CTX_start(&ctx);
-	tmp = BN_CTX_get(&ctx);
+	ctx = BN_CTX_new();
+	if (ctx == NULL) goto err;
+	BN_CTX_start(ctx);
+	tmp = BN_CTX_get(ctx);
 	
 	if (dh->priv_key == NULL)
 		{
-		DHerr(DH_F_DH_COMPUTE_KEY,DH_R_NO_PRIVATE_VALUE);
+		DHerr(DH_F_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(&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 (!ENGINE_get_DH(dh->engine)->bn_mod_exp(dh, tmp, pub_key,
-				dh->priv_key,dh->p,&ctx,mont))
+	if (!dh->meth->bn_mod_exp(dh, tmp, pub_key, dh->priv_key,dh->p,ctx,mont))
 		{
-		DHerr(DH_F_DH_COMPUTE_KEY,ERR_R_BN_LIB);
+		DHerr(DH_F_COMPUTE_KEY,ERR_R_BN_LIB);
 		goto err;
 		}
 
 	ret=BN_bn2bin(tmp,key);
 err:
-	BN_CTX_end(&ctx);
-	BN_CTX_free(&ctx);
+	BN_CTX_end(ctx);
+	BN_CTX_free(ctx);
 	return(ret);
 	}
 
@@ -192,7 +220,10 @@ 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);
@@ -211,6 +242,6 @@ static int dh_init(DH *dh)
 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);
 	}