From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 45605C3F68F for ; Mon, 16 Dec 2019 17:52:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1F01C20733 for ; Mon, 16 Dec 2019 17:52:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576518733; bh=/0oP2aOmkN4YPfnfmuZKKa5D6e4/N1L0vU89h5RbObk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=zszXHUzz0A6Ut40xwqFPOWNA88+TZlVwCxz3OK+mrDEuZTfI/J8yqKPJbyoaXTSpP b/3mCeix2Qta6ogMyZi3fRse+k/QVlBafY7EMlcECzIW0RstRKXX02U11WyBBZPKex xtiZFQdz7v+OKnTxegf8jG3+IkgrNAQT7xotRN4I= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727337AbfLPRwI (ORCPT ); Mon, 16 Dec 2019 12:52:08 -0500 Received: from mail.kernel.org ([198.145.29.99]:43308 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726438AbfLPRwH (ORCPT ); Mon, 16 Dec 2019 12:52:07 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0D9902166E; Mon, 16 Dec 2019 17:52:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576518726; bh=/0oP2aOmkN4YPfnfmuZKKa5D6e4/N1L0vU89h5RbObk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cZy6slkSskF6yqk1d3lkA7Sq61sxj563aQTyFz0FzyAZ3nkVbxKLgBHXJWqooOOhm bXqbdR8RkzghTLMpi3ndwiPUk5Mj2KnwqD++ARFSO9y9IoWH+29Ua91JSjongrjVDJ SxReNY+M9DlwldLrCcdOeyqOjKY4VMnbDoaO9Aec= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vitaly Chikunov , Herbert Xu , Sasha Levin Subject: [PATCH 4.14 041/267] crypto: ecc - check for invalid values in the key verification test Date: Mon, 16 Dec 2019 18:46:07 +0100 Message-Id: <20191216174853.358885933@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20191216174848.701533383@linuxfoundation.org> References: <20191216174848.701533383@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Vitaly Chikunov [ Upstream commit 2eb4942b6609d35a4e835644a33203b0aef7443d ] Currently used scalar multiplication algorithm (Matthieu Rivain, 2011) have invalid values for scalar == 1, n-1, and for regularized version n-2, which was previously not checked. Verify that they are not used as private keys. Signed-off-by: Vitaly Chikunov Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin --- crypto/ecc.c | 42 ++++++++++++++++++++++++++---------------- 1 file changed, 26 insertions(+), 16 deletions(-) diff --git a/crypto/ecc.c b/crypto/ecc.c index 18f32f2a5e1c9..3b422e24e647e 100644 --- a/crypto/ecc.c +++ b/crypto/ecc.c @@ -904,30 +904,43 @@ static inline void ecc_swap_digits(const u64 *in, u64 *out, out[i] = __swab64(in[ndigits - 1 - i]); } -int ecc_is_key_valid(unsigned int curve_id, unsigned int ndigits, - const u64 *private_key, unsigned int private_key_len) +static int __ecc_is_key_valid(const struct ecc_curve *curve, + const u64 *private_key, unsigned int ndigits) { - int nbytes; - const struct ecc_curve *curve = ecc_get_curve(curve_id); + u64 one[ECC_MAX_DIGITS] = { 1, }; + u64 res[ECC_MAX_DIGITS]; if (!private_key) return -EINVAL; - nbytes = ndigits << ECC_DIGITS_TO_BYTES_SHIFT; - - if (private_key_len != nbytes) + if (curve->g.ndigits != ndigits) return -EINVAL; - if (vli_is_zero(private_key, ndigits)) + /* Make sure the private key is in the range [2, n-3]. */ + if (vli_cmp(one, private_key, ndigits) != -1) return -EINVAL; - - /* Make sure the private key is in the range [1, n-1]. */ - if (vli_cmp(curve->n, private_key, ndigits) != 1) + vli_sub(res, curve->n, one, ndigits); + vli_sub(res, res, one, ndigits); + if (vli_cmp(res, private_key, ndigits) != 1) return -EINVAL; return 0; } +int ecc_is_key_valid(unsigned int curve_id, unsigned int ndigits, + const u64 *private_key, unsigned int private_key_len) +{ + int nbytes; + const struct ecc_curve *curve = ecc_get_curve(curve_id); + + nbytes = ndigits << ECC_DIGITS_TO_BYTES_SHIFT; + + if (private_key_len != nbytes) + return -EINVAL; + + return __ecc_is_key_valid(curve, private_key, ndigits); +} + /* * ECC private keys are generated using the method of extra random bits, * equivalent to that described in FIPS 186-4, Appendix B.4.1. @@ -971,11 +984,8 @@ int ecc_gen_privkey(unsigned int curve_id, unsigned int ndigits, u64 *privkey) if (err) return err; - if (vli_is_zero(priv, ndigits)) - return -EINVAL; - - /* Make sure the private key is in the range [1, n-1]. */ - if (vli_cmp(curve->n, priv, ndigits) != 1) + /* Make sure the private key is in the valid range. */ + if (__ecc_is_key_valid(curve, priv, ndigits)) return -EINVAL; ecc_swap_digits(priv, privkey, ndigits); -- 2.20.1