[openssl-dev] [openssl.org #3641] [PATCH] EC_KEY_generate always overwrites private key All OS 1.0.1j

[kruegerb via RT]

The do-while loop that uses BN_rand_range to set the private key is 
outside of and following the block that tests if the private key is set. 
This results in the private key always being set to a random value even 
when a private key has been provided. The proposed patch is to move the 
do-while loop inside the private key test for NULL block. See attached.

-------------- next part --------------
int EC_KEY_generate_key(EC_KEY *eckey)
	{	
	int	ok = 0;
	BN_CTX	*ctx = NULL;
	BIGNUM	*priv_key = NULL, *order = NULL;
	EC_POINT *pub_key = NULL;

#ifdef OPENSSL_FIPS
	if (FIPS_mode())
		return FIPS_ec_key_generate_key(eckey);
#endif

	if (!eckey || !eckey->group)
		{
		ECerr(EC_F_EC_KEY_GENERATE_KEY, ERR_R_PASSED_NULL_PARAMETER);
		return 0;
		}

	if ((order = BN_new()) == NULL) goto err;
	if ((ctx = BN_CTX_new()) == NULL) goto err;

	if (eckey->priv_key == NULL)
		{
		priv_key = BN_new();
		if (priv_key == NULL)
			goto err;

                do
                        if (!BN_rand_range(priv_key, order))
                                goto err;
                while (BN_is_zero(priv_key));
		}
	else
		priv_key = eckey->priv_key;

	if (!EC_GROUP_get_order(eckey->group, order, ctx))
		goto err;

	if (eckey->pub_key == NULL)
		{
		pub_key = EC_POINT_new(eckey->group);
		if (pub_key == NULL)
			goto err;
		}
	else
		pub_key = eckey->pub_key;

	if (!EC_POINT_mul(eckey->group, pub_key, priv_key, NULL, NULL, ctx))
		goto err;

	eckey->priv_key = priv_key;
	eckey->pub_key  = pub_key;

	ok=1;

err:	
	if (order)
		BN_free(order);
	if (pub_key  != NULL && eckey->pub_key  == NULL)
		EC_POINT_free(pub_key);
	if (priv_key != NULL && eckey->priv_key == NULL)
		BN_free(priv_key);
	if (ctx != NULL)
		BN_CTX_free(ctx);
	return(ok);
	}