From patchwork Thu Feb 16 20:14:02 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Bottomley X-Patchwork-Id: 13143712 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 EF2F2C61DA4 for ; Thu, 16 Feb 2023 20:16:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229888AbjBPUQR (ORCPT ); Thu, 16 Feb 2023 15:16:17 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37146 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229520AbjBPUQQ (ORCPT ); Thu, 16 Feb 2023 15:16:16 -0500 Received: from bedivere.hansenpartnership.com (bedivere.hansenpartnership.com [IPv6:2607:fcd0:100:8a00::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 959CE4C6D7; Thu, 16 Feb 2023 12:16:15 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=hansenpartnership.com; s=20151216; t=1676578575; bh=SYvWaFlWqScJVSJQhSfehs2czXvOZYIZhECUkS1mEAI=; h=From:To:Subject:Date:Message-Id:In-Reply-To:References:From; b=YxtAGVIoNu1YUiish7DZd3Gge+JHJFZl5qfUEAgHiAcXHqdsqGltdLzvbfe0/rxSF Fz1ls+sQnhS+NPRt4YAvATCnwvhVQEL74aC1RUnqZU6oj6bhQqZM5F8k/NrTr6GDom PvhQSDG1coJhln9SUEs0lTxZlGhZd6jCxUnrHC7U= Received: from localhost (localhost [127.0.0.1]) by bedivere.hansenpartnership.com (Postfix) with ESMTP id 62AB11286F45; Thu, 16 Feb 2023 15:16:15 -0500 (EST) Received: from bedivere.hansenpartnership.com ([127.0.0.1]) by localhost (bedivere.hansenpartnership.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id jZRZ_n6Wrqoq; Thu, 16 Feb 2023 15:16:15 -0500 (EST) Received: from lingrow.int.hansenpartnership.com (unknown [153.66.160.227]) by bedivere.hansenpartnership.com (Postfix) with ESMTP id AF8B21286E47; Thu, 16 Feb 2023 15:16:14 -0500 (EST) From: James Bottomley To: linux-integrity@vger.kernel.org Cc: Jarkko Sakkinen , keyrings@vger.kernel.org, Ard Biesheuvel Subject: [PATCH 04/12] tpm: add cursor based buffer functions for response parsing Date: Thu, 16 Feb 2023 15:14:02 -0500 Message-Id: <20230216201410.15010-5-James.Bottomley@HansenPartnership.com> X-Mailer: git-send-email 2.35.3 In-Reply-To: <20230216201410.15010-1-James.Bottomley@HansenPartnership.com> References: <20230216201410.15010-1-James.Bottomley@HansenPartnership.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: keyrings@vger.kernel.org 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. 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.