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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2B005C7EE2D for ; Mon, 27 Feb 2023 08:48:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230495AbjB0Ise (ORCPT ); Mon, 27 Feb 2023 03:48:34 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36160 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229742AbjB0IsH (ORCPT ); Mon, 27 Feb 2023 03:48:07 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 51A67252A6; Mon, 27 Feb 2023 00:40:37 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 1DD33B80BE8; Mon, 27 Feb 2023 08:34:04 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2BC76C433EF; Mon, 27 Feb 2023 08:34:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1677486842; bh=daN4vxGRyKHsdZInFbqx1YolKOv5AHiq+a5Oe5Jn9Wo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=DQH+P69bpThkbkW+NT0Sdt+nxbeE+/RtDKCuENW1QCHhHQIPLQVh6Hd7QoXd2eshH SCkOxOyrbotUisEQnX2LZ6Cyb50BO9lnQxmI1UQCKTBZ2BjupWltSAZhIlxekF3Yej 5mqp8H1FxwTE/UtwO4YuSHGep9rdyZRzgSx8mO0bdIJML49R5nfz40EmNnwNT/S9Ue jvnQCI2AwOJ/RM6W1bR79JgULY+QHhYONcf0qA987cCNvv0w8i5R1N/LtVGRY+j4zU u33zAf2htQLKzOLzs2LMFtXgotqOLP1s6doV5mTqogx1S7zu3nCPPI+tRSRHxdTRHo SQgtiL1HdDIVg== Date: Mon, 27 Feb 2023 10:34:00 +0200 From: Jarkko Sakkinen To: James Bottomley Cc: linux-integrity@vger.kernel.org, keyrings@vger.kernel.org, Ard Biesheuvel Subject: Re: [PATCH 04/12] tpm: add cursor based buffer functions for response parsing Message-ID: References: <20230216201410.15010-1-James.Bottomley@HansenPartnership.com> <20230216201410.15010-5-James.Bottomley@HansenPartnership.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230216201410.15010-5-James.Bottomley@HansenPartnership.com> Precedence: bulk List-ID: X-Mailing-List: keyrings@vger.kernel.org On Thu, Feb 16, 2023 at 03:14:02PM -0500, James Bottomley wrote: > Once we have encryption and authentication, marshalling and > unmarshalling sessions becomes hugely complex. Add cursor based > functions which update the current pointer to make response parsing > easier. You need to properly introduce the concept of cursor based function, and how that maps into implementation. I understand absolutely nothing of the change just by reading the commit message, it is pretty much useless peace of text. > > Signed-off-by: James Bottomley > --- > drivers/char/tpm/tpm-buf.c | 29 +++++++++++++++++++++++++++++ > include/linux/tpm.h | 3 +++ > 2 files changed, 32 insertions(+) > > diff --git a/drivers/char/tpm/tpm-buf.c b/drivers/char/tpm/tpm-buf.c > index 292c6f14f72c..b76158f9bcd0 100644 > --- a/drivers/char/tpm/tpm-buf.c > +++ b/drivers/char/tpm/tpm-buf.c > @@ -7,6 +7,8 @@ > #include > #include > > +#include > + > static int __tpm_buf_init(struct tpm_buf *buf) > { > buf->data = (u8 *)__get_free_page(GFP_KERNEL); > @@ -154,3 +156,30 @@ void tpm_buf_append_2b(struct tpm_buf *buf, struct tpm_buf *tpm2b) > tpm_buf_reset_int(tpm2b); > } > EXPORT_SYMBOL_GPL(tpm_buf_append_2b); > + > +/* functions for unmarshalling data and moving the cursor */ > +u8 tpm_get_inc_u8(const u8 **ptr) > +{ > + return *((*ptr)++); > +} > +EXPORT_SYMBOL_GPL(tpm_get_inc_u8); > + > +u16 tpm_get_inc_u16(const u8 **ptr) > +{ > + u16 val; > + > + val = get_unaligned_be16(*ptr); > + *ptr += sizeof(val); > + return val; > +} > +EXPORT_SYMBOL_GPL(tpm_get_inc_u16); > + > +u32 tpm_get_inc_u32(const u8 **ptr) > +{ > + u32 val; > + > + val = get_unaligned_be32(*ptr); > + *ptr += sizeof(val); > + return val; > +} > +EXPORT_SYMBOL_GPL(tpm_get_inc_u32); > diff --git a/include/linux/tpm.h b/include/linux/tpm.h > index f2d4dab6d832..f7cff1d114b0 100644 > --- a/include/linux/tpm.h > +++ b/include/linux/tpm.h > @@ -335,6 +335,9 @@ void tpm_buf_append_u8(struct tpm_buf *buf, const u8 value); > void tpm_buf_append_u16(struct tpm_buf *buf, const u16 value); > void tpm_buf_append_u32(struct tpm_buf *buf, const u32 value); > void tpm_buf_append_2b(struct tpm_buf *buf, struct tpm_buf *tpm2b); > +u8 tpm_get_inc_u8(const u8 **ptr); > +u16 tpm_get_inc_u16(const u8 **ptr); > +u32 tpm_get_inc_u32(const u8 **ptr); > > /* > * Check if TPM device is in the firmware upgrade mode. > -- > 2.35.3 > BR, Jarkko