From nobody Wed Dec 17 22:59:27 2025 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 696E8C61D85 for ; Tue, 21 Nov 2023 21:17:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234575AbjKUVSA (ORCPT ); Tue, 21 Nov 2023 16:18:00 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50642 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234578AbjKUVRw (ORCPT ); Tue, 21 Nov 2023 16:17:52 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 950B510E2 for ; Tue, 21 Nov 2023 13:17:43 -0800 (PST) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A9C15C433C8; Tue, 21 Nov 2023 21:17:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1700601463; bh=Gw6t4yKIoJH0jVM58wLhTCrKliCl3oXQG36AlAIlWHE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=i3N63W7O+mAyzycndV7HyNu7prGb6dNGDn1fHnPWrHEGNyi10ffUvgBuoZP5OIbil tIr0Bd+r+0S89lcmCNo0LL9PyY5EyjJDPg+iKQHNCvfU6NWtEn0cVO+UMnOsEF441o wkSb43Xk7pWNJUoi6+PE40PH1EHIpmMiZC4kqiYilnISC1xopZ23dA39CBanFkczY9 TIGq0p4yK4UVAydvppuqaS4RvGBNj/4t5v4Ah/OD/23Imtts/iJjrBRmDGYhvWdObV gxWuUH8+JmpLmvA/hfPGEXt1bWBFrVDxkMUiqM5eTZ6lcE+yPcLycDYtp7W5DG9OFG EVoNTpZjI+kfg== From: Jarkko Sakkinen To: linux-integrity@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Jarkko Sakkinen , James Bottomley , William Roberts , Stefan Berger , David Howells , Jason Gunthorpe , Mimi Zohar , Mario Limonciello , Jerry Snitselaar , Peter Huewe , James Bottomley , Paul Moore , James Morris , "Serge E. Hallyn" , Julien Gomes Subject: [PATCH v4 6/8] tpm: TPM2B formatted buffers Date: Tue, 21 Nov 2023 23:17:15 +0200 Message-ID: <20231121211717.31681-7-jarkko@kernel.org> X-Mailer: git-send-email 2.42.1 In-Reply-To: <20231121211717.31681-1-jarkko@kernel.org> References: <20231121211717.31681-1-jarkko@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Declare tpm_buf_init_sized() and tpm_buf_reset_sized() for creating TPM2B formatted buffers. These buffers are also known as sized buffers in the specifications and literature. Signed-off-by: Jarkko Sakkinen --- v2: [2021-11-21] Refine the API according to the comments for https://lore.kernel.org/linux-integrity/20231024011531.442587-5-jarkko@= kernel.org/ --- drivers/char/tpm/tpm-buf.c | 38 +++++++++++++++++++++++++++++++++++--- include/linux/tpm.h | 4 ++++ 2 files changed, 39 insertions(+), 3 deletions(-) diff --git a/drivers/char/tpm/tpm-buf.c b/drivers/char/tpm/tpm-buf.c index 545d9c74abf1..12bfade11372 100644 --- a/drivers/char/tpm/tpm-buf.c +++ b/drivers/char/tpm/tpm-buf.c @@ -48,6 +48,36 @@ void tpm_buf_reset(struct tpm_buf *buf, u16 tag, u32 ord= inal) } EXPORT_SYMBOL_GPL(tpm_buf_reset); =20 +/** + * tpm_buf_init_sized() - Allocate and initialize a sized (TPM2B) buffer + * @buf: A @tpm_buf + * + * Return: 0 or -ENOMEM + */ +int tpm_buf_init_sized(struct tpm_buf *buf) +{ + buf->data =3D (u8 *)__get_free_page(GFP_KERNEL); + if (!buf->data) + return -ENOMEM; + + tpm_buf_reset_sized(buf); + return 0; +} +EXPORT_SYMBOL_GPL(tpm_buf_init_sized); + +/** + * tpm_buf_reset_sized() - Initialize a sized buffer + * @buf: A &tpm_buf + */ +void tpm_buf_reset_sized(struct tpm_buf *buf) +{ + buf->flags =3D TPM_BUF_TPM2B; + buf->length =3D 2; + buf->data[0] =3D 0; + buf->data[1] =3D 0; +} +EXPORT_SYMBOL_GPL(tpm_buf_reset_sized); + void tpm_buf_destroy(struct tpm_buf *buf) { free_page((unsigned long)buf->data); @@ -73,8 +103,6 @@ EXPORT_SYMBOL_GPL(tpm_buf_length); */ void tpm_buf_append(struct tpm_buf *buf, const u8 *new_data, u16 new_lengt= h) { - struct tpm_header *head =3D (struct tpm_header *)buf->data; - /* Return silently if overflow has already happened. */ if (buf->flags & TPM_BUF_OVERFLOW) return; @@ -87,7 +115,11 @@ void tpm_buf_append(struct tpm_buf *buf, const u8 *new_= data, u16 new_length) =20 memcpy(&buf->data[buf->length], new_data, new_length); buf->length +=3D new_length; - head->length =3D cpu_to_be32(buf->length); + + if (buf->flags & TPM_BUF_TPM2B) + ((__be16 *)buf->data)[0] =3D cpu_to_be16(buf->length - 2); + else + ((struct tpm_header *)buf->data)->length =3D cpu_to_be32(buf->length); } EXPORT_SYMBOL_GPL(tpm_buf_append); =20 diff --git a/include/linux/tpm.h b/include/linux/tpm.h index 1d7b39b5c383..715db4a91c1f 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -300,6 +300,8 @@ struct tpm_header { enum tpm_buf_flags { /* the capacity exceeded: */ TPM_BUF_OVERFLOW =3D BIT(0), + /* TPM2B format: */ + TPM_BUF_TPM2B =3D BIT(1), }; =20 /* @@ -328,6 +330,8 @@ struct tpm2_hash { =20 int tpm_buf_init(struct tpm_buf *buf, u16 tag, u32 ordinal); void tpm_buf_reset(struct tpm_buf *buf, u16 tag, u32 ordinal); +int tpm_buf_init_sized(struct tpm_buf *buf); +void tpm_buf_reset_sized(struct tpm_buf *buf); void tpm_buf_destroy(struct tpm_buf *buf); u32 tpm_buf_length(struct tpm_buf *buf); void tpm_buf_append(struct tpm_buf *buf, const u8 *new_data, u16 new_lengt= h); --=20 2.42.1