From nobody Sat Feb 7 18:23:02 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B53A318787A; Wed, 10 Dec 2025 14:39:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765377591; cv=none; b=KzTlnrtvui7FbDMe/zxmosPj+gQuCkSrrJmQbcYW4sD2fb38Em+11Pp4yXFkNTwFTPTyuslmSBAPqKwmI8xP/tl6LCxZZSrC8dRpyNN001JovAL6kD79vczNEFeFsMGAK5ZzeORr9fvFc9cNeltxWq2y6DdZ8TzacY/MCBEeRTc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765377591; c=relaxed/simple; bh=YUYqIvNjXnvmL0CNkyW+ra2WzRNZMTP9cgmJvuV1o7E=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=NbuWnO4kXow90nTK1kpFj8FN9Vcq7oTNrM/7gEoF+MPToS3zZ/2lb3XPSxKSolP2rdjWga18dGkmR02hIMFknOuCI/eazEdED5Njen0W8xxR24KfjgvtWyzuP7jTlzTA9BRB9DrHIt7DEEuT0tH6xcbwoxSD5CJ9fzBtWXhrcr0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=RpMJ3q+l; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="RpMJ3q+l" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DDD7CC4CEF7; Wed, 10 Dec 2025 14:39:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1765377591; bh=YUYqIvNjXnvmL0CNkyW+ra2WzRNZMTP9cgmJvuV1o7E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RpMJ3q+lsapbu1e9o3qI1l+MorsWLFV7+fERjiGFZX9z5mXr/mM0hsN0pyfaSq2dM yeMg2OAflNUyVndnDWZn66aGPfHwz+HtTjfgrf5OhrYW93xJNi3JLapIr1KN8kZby+ sCJ/elGWE7NuXFytzVf25OmdAfH2J4iv9FlAY0Z0UE//o67sMmnV3TnrkhEAUFmO0v YlmpnIuqCD43dMq9aUyjCn1xu9X5B+H/zn9xpHNgAC9RAJNmg28h7NNdhYEhUDyamT Yj5mDilY32C9TExvx0AhvzR2cCrVuL56/wwlz0mh7+3TqYyZc89BgcEIqF+7uTUZE/ QmaZYuktl8uUg== From: Jarkko Sakkinen To: linux-integrity@vger.kernel.org Cc: Jarkko Sakkinen , David Howells , Paul Moore , James Morris , "Serge E. Hallyn" , James Bottomley , Mimi Zohar , keyrings@vger.kernel.org (open list:KEYS/KEYRINGS), linux-security-module@vger.kernel.org (open list:SECURITY SUBSYSTEM), linux-kernel@vger.kernel.org (open list) Subject: [PATCH v3 1/7] KEYS: trusted: Remove dead branch from tpm2_unseal_cmd Date: Wed, 10 Dec 2025 16:39:33 +0200 Message-ID: <20251210143940.264191-2-jarkko@kernel.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251210143940.264191-1-jarkko@kernel.org> References: <20251210143940.264191-1-jarkko@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" TPM2_Unseal requires TPM2_ST_SESSIONS, and tpm2_unseal_cmd() always does set up either password or HMAC session. Remove the branch in tpm2_unseal_cmd() conditionally setting TPM2_ST_NO_SESSIONS. It is faulty but luckily it is never exercised at run-time, and thus does not cause regressions. Signed-off-by: Jarkko Sakkinen --- security/keys/trusted-keys/trusted_tpm2.c | 10 +--------- 1 file changed, 1 insertion(+), 9 deletions(-) diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trus= ted-keys/trusted_tpm2.c index 9074ae1a5896..27424e1a4a63 100644 --- a/security/keys/trusted-keys/trusted_tpm2.c +++ b/security/keys/trusted-keys/trusted_tpm2.c @@ -450,9 +450,7 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip, struct trusted_key_options *options, u32 blob_handle) { - struct tpm_header *head; u16 data_len; - int offset; u8 *data; int rc; =20 @@ -488,14 +486,8 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip, tpm_buf_append_u16(buf, options->blobauth_len); tpm_buf_append(buf, options->blobauth, options->blobauth_len); =20 - if (tpm2_chip_auth(chip)) { + if (tpm2_chip_auth(chip)) tpm_buf_append_hmac_session(chip, buf, TPM2_SA_ENCRYPT, NULL, 0); - } else { - offset =3D buf->handles * 4 + TPM_HEADER_SIZE; - head =3D (struct tpm_header *)buf->data; - if (tpm_buf_length(buf) =3D=3D offset) - head->tag =3D cpu_to_be16(TPM2_ST_NO_SESSIONS); - } } =20 rc =3D tpm_buf_fill_hmac_session(chip, buf); --=20 2.52.0 From nobody Sat Feb 7 18:23:02 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BB3931E3DED; Wed, 10 Dec 2025 14:39:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765377596; cv=none; b=fe7wuTf8eZtEKPJPxius+LWUhrvY3wBaXwyNB1xVC7wE4LSpX7gHW2VWBuHJ64IeWGJtG8iiRnqq9cCuL3PPoNx5AzdVEE6KFmRCP/6rekyGfk6KH0zR8Vx+7TULdms2WK4bZFm1TbwzNITeDle70kfK4aNV6sK1HRZBk7lIyHI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765377596; c=relaxed/simple; bh=+/iE2nY+wCSKxR3DAC0xcgYWEXR/x9Hj89HmjeyMfS0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=omsDQAm0z90gbiPEvdHR7UKfOgKO2xJJ5vG1WFKw2qgO9sMR9fps1cMvqH9RmqPFFqIK2CchtKVT4hbZb0QQKA1+xOJ2lBWc+HOjl5Xm3Utgz1VYbh0mCTIZQvEoCwlcXydZEeIP319MG29ZImzFbgPzggEmhKDHjICg9lCbC3E= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Xya1WqHH; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Xya1WqHH" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C87ACC113D0; Wed, 10 Dec 2025 14:39:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1765377596; bh=+/iE2nY+wCSKxR3DAC0xcgYWEXR/x9Hj89HmjeyMfS0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Xya1WqHHlOyI/RjPadfwjhmYaIvzLxy5tbsdp34fFdLNA8eWYEQQkp1S98eaHPluF kjgQQqfIsrPLQCkWVeDMykM7CLPSZRwmL9ZFzK9aIng3P4PesBF97aRIg7Kx4qpb9I JpalTFS8UixZzPwlhQEVy3sPweqC9f2Q6FXYEIIF4mTykOl9j5tn8nLoWRY2epGErN mh4nKFCuWZ5NbDoAGT9uqzh7ltzi8yv7gLtmb1x0RszU66v4W4G+TdFI3SKCsBPC3h HIiQ4VIWJkiUWThKuV00AaUN+I1ei7frVs5DNiTi4bv6SFp2q12r44cL8NT83uX4wK IfoHeCqzCbFkg== From: Jarkko Sakkinen To: linux-integrity@vger.kernel.org Cc: Jarkko Sakkinen , Peter Huewe , Jason Gunthorpe , David Howells , Paul Moore , James Morris , "Serge E. Hallyn" , linux-kernel@vger.kernel.org (open list), keyrings@vger.kernel.org (open list:KEYS/KEYRINGS), linux-security-module@vger.kernel.org (open list:SECURITY SUBSYSTEM) Subject: [PATCH v3 2/7] tpm2-sessions: Define TPM2_NAME_MAX_SIZE Date: Wed, 10 Dec 2025 16:39:34 +0200 Message-ID: <20251210143940.264191-3-jarkko@kernel.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251210143940.264191-1-jarkko@kernel.org> References: <20251210143940.264191-1-jarkko@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" This is somewhat cosmetic change but it does serve a purpose on tracking the value set for the maximum length of TPM names, and to clearly states what components it is composed of. It also anchors the value so that when buffers are declared for this particular purpose, the same value is used for the capacity. Signed-off-by: Jarkko Sakkinen --- v2: - Rename TPM2_NAME_SIZE as TPM2_NULL_NAME_SIZE. --- drivers/char/tpm/tpm-sysfs.c | 2 +- drivers/char/tpm/tpm2-sessions.c | 2 +- include/linux/tpm.h | 37 +++++++++++++++++++++----------- 3 files changed, 27 insertions(+), 14 deletions(-) diff --git a/drivers/char/tpm/tpm-sysfs.c b/drivers/char/tpm/tpm-sysfs.c index f5dcadb1ab3c..0f321c307bc6 100644 --- a/drivers/char/tpm/tpm-sysfs.c +++ b/drivers/char/tpm/tpm-sysfs.c @@ -313,7 +313,7 @@ static ssize_t null_name_show(struct device *dev, struc= t device_attribute *attr, char *buf) { struct tpm_chip *chip =3D to_tpm_chip(dev); - int size =3D TPM2_NAME_SIZE; + int size =3D TPM2_NULL_NAME_SIZE; =20 bin2hex(buf, chip->null_key_name, size); size *=3D 2; diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessi= ons.c index 79f27a46bd7f..a0c88fb1804c 100644 --- a/drivers/char/tpm/tpm2-sessions.c +++ b/drivers/char/tpm/tpm2-sessions.c @@ -137,7 +137,7 @@ struct tpm2_auth { * we must compute and remember */ u32 name_h[AUTH_MAX_NAMES]; - u8 name[AUTH_MAX_NAMES][2 + SHA512_DIGEST_SIZE]; + u8 name[AUTH_MAX_NAMES][TPM2_MAX_NAME_SIZE]; }; =20 #ifdef CONFIG_TCG_TPM2_HMAC diff --git a/include/linux/tpm.h b/include/linux/tpm.h index 42e2a091f43d..922a43ef23b5 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -28,9 +28,33 @@ #define TPM_DIGEST_SIZE 20 /* Max TPM v1.2 PCR size */ #define TPM_BUFSIZE 4096 =20 +/* + * SHA-512 is, as of today, the largest digest in the TCG algorithm reposi= tory. + */ #define TPM2_MAX_DIGEST_SIZE SHA512_DIGEST_SIZE + +/* + * A TPM name digest i.e., TPMT_HA, is a concatenation of TPM_ALG_ID of the + * name algorithm and hash of TPMT_PUBLIC. + */ +#define TPM2_MAX_NAME_SIZE (TPM2_MAX_DIGEST_SIZE + 2) + +/* + * The maximum number of PCR banks. + */ #define TPM2_MAX_PCR_BANKS 8 =20 +/* + * fixed define for the size of a name. This is actually HASHALG size + * plus 2, so 32 for SHA256 + */ +#define TPM2_NULL_NAME_SIZE 34 + +/* + * The maximum size for an object context + */ +#define TPM2_MAX_CONTEXT_SIZE 4096 + struct tpm_chip; struct trusted_key_payload; struct trusted_key_options; @@ -140,17 +164,6 @@ struct tpm_chip_seqops { /* fixed define for the curve we use which is NIST_P256 */ #define EC_PT_SZ 32 =20 -/* - * fixed define for the size of a name. This is actually HASHALG size - * plus 2, so 32 for SHA256 - */ -#define TPM2_NAME_SIZE 34 - -/* - * The maximum size for an object context - */ -#define TPM2_MAX_CONTEXT_SIZE 4096 - struct tpm_chip { struct device dev; struct device devs; @@ -212,7 +225,7 @@ struct tpm_chip { /* saved context for NULL seed */ u8 null_key_context[TPM2_MAX_CONTEXT_SIZE]; /* name of NULL seed */ - u8 null_key_name[TPM2_NAME_SIZE]; + u8 null_key_name[TPM2_NULL_NAME_SIZE]; u8 null_ec_key_x[EC_PT_SZ]; u8 null_ec_key_y[EC_PT_SZ]; struct tpm2_auth *auth; --=20 2.52.0 From nobody Sat Feb 7 18:23:02 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1B5EA221DAD; Wed, 10 Dec 2025 14:40:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765377602; cv=none; b=nXzKo+4l1XwLTpyVjy03R39wMMk/cMKxWFuxibLUD/0lW+P6gF9z3Sy5nNKa4qjTEYottHvNiorM4+noOJCO6q1r9PEMiViaXmZ5EBGsjg/vuEETzeJrnNyTFlgzGY6D69XtZQdf7dmL8Ih5cf37Db6Uv8vCxu9VUXFRB5wvlx0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765377602; c=relaxed/simple; bh=FImZXxsx3vdik3A+AE8B0smFOqFlJAYmfBu9rXDotvI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SWDGLOeS/D6DbFHFG80xcsIUM0fNPGY6Xi/0dnhWh1Krc6t6qscCYzCZx0DXOHDmPQJzFBzGEEtQyIhRGhZBPjvsg9PgqQ969VUgfYXTCBFo5k62py6jq+ORJ77k6ZuP9r6B3FOb16XXv1jq1fVh7KQaBBDdCvGSpQtAe1nPp4s= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=hjvW5tgt; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="hjvW5tgt" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 23BB9C4CEF1; Wed, 10 Dec 2025 14:40:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1765377601; bh=FImZXxsx3vdik3A+AE8B0smFOqFlJAYmfBu9rXDotvI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hjvW5tgtE9a5AZbhHsfEQSt+Bn21lpcfpBUKalIhgaloQJ1Ub93EcNGefzw2WYfD1 PE8zH3sPh3SRkeLHFVfbLo98gCMUrngABptiO+D4AWq5FmRdF/Cq1gDMpRblqtjYmH XRkLzIJlBchQwmyYOHXxfAZtUX1BwID+7jYmyd6mmZvRcI32mxiP0ZeTqBhYf7su6u b0GJZv//yERuFh0KVo9ATGlq/SH6gi28JMdBEvYzfbH6jPbt4uIctASovAIywgd6Gr mkdX7cANj7uZRBXMtPv95MIZelrGtm7z5tnS6yXFV/j/i7KGH1qC4rZNEy/jnOklMr mslyOKFHKqcmQ== From: Jarkko Sakkinen To: linux-integrity@vger.kernel.org Cc: Jarkko Sakkinen , Peter Huewe , Jason Gunthorpe , David Howells , Paul Moore , James Morris , "Serge E. Hallyn" , James Bottomley , Mimi Zohar , linux-kernel@vger.kernel.org (open list), keyrings@vger.kernel.org (open list:KEYS/KEYRINGS), linux-security-module@vger.kernel.org (open list:SECURITY SUBSYSTEM) Subject: [PATCH v3 3/7] KEYS: trusted: Re-orchestrate tpm2_read_public() calls Date: Wed, 10 Dec 2025 16:39:35 +0200 Message-ID: <20251210143940.264191-4-jarkko@kernel.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251210143940.264191-1-jarkko@kernel.org> References: <20251210143940.264191-1-jarkko@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" tpm2_load_cmd() and tpm2_unseal_cmd() use the same parent, and calls to tpm_buf_append_name() cause the exact same TPM2_ReadPublic command to be sent to the chip, causing unnecessary traffic. 1. Export tpm2_read_public in order to make it callable from 'trusted_tpm2'. 2. Re-orchestrate tpm2_seal_trusted() and tpm2_unseal_trusted() in order to halve the name resolutions required: 2a. Move tpm2_read_public() calls into trusted_tpm2. 2b. Pass TPM name to tpm_buf_append_name(). 2c. Rework tpm_buf_append_name() to use the pre-resolved name. Signed-off-by: Jarkko Sakkinen --- drivers/char/tpm/tpm2-cmd.c | 3 +- drivers/char/tpm/tpm2-sessions.c | 95 +++++------------ include/linux/tpm.h | 10 +- security/keys/trusted-keys/trusted_tpm2.c | 124 ++++++++++++++-------- 4 files changed, 118 insertions(+), 114 deletions(-) diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c index 543c1c62c938..436ee82620e4 100644 --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -199,7 +199,8 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND); =20 if (!disable_pcr_integrity) { - rc =3D tpm_buf_append_name(chip, buf, pcr_idx, NULL); + rc =3D tpm_buf_append_name(chip, buf, pcr_idx, (u8 *)&pcr_idx, + sizeof(u32)); if (rc) return rc; tpm_buf_append_hmac_session(chip, buf, 0, NULL, 0); diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessi= ons.c index a0c88fb1804c..0816a91134fc 100644 --- a/drivers/char/tpm/tpm2-sessions.c +++ b/drivers/char/tpm/tpm2-sessions.c @@ -136,8 +136,8 @@ struct tpm2_auth { * handle, but they are part of the session by name, which * we must compute and remember */ - u32 name_h[AUTH_MAX_NAMES]; u8 name[AUTH_MAX_NAMES][TPM2_MAX_NAME_SIZE]; + u16 name_size_tbl[AUTH_MAX_NAMES]; }; =20 #ifdef CONFIG_TCG_TPM2_HMAC @@ -163,7 +163,17 @@ static int name_size(const u8 *name) } } =20 -static int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name) +/** + * tpm2_read_public: Resolve TPM name for a handle + * @chip: TPM chip to use. + * @handle: TPM handle. + * @name: A buffer for returning the name blob. Must have a + * capacity of 'SHA512_DIGET_SIZE + 2' bytes at minimum + * + * Returns size of TPM handle name of success. + * Returns tpm_transmit_cmd error codes when TPM2_ReadPublic fails. + */ +int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name) { u32 mso =3D tpm2_handle_mso(handle); off_t offset =3D TPM_HEADER_SIZE; @@ -212,14 +222,16 @@ static int tpm2_read_public(struct tpm_chip *chip, u3= 2 handle, void *name) memcpy(name, &buf->data[offset], rc); return name_size_alg; } +EXPORT_SYMBOL_GPL(tpm2_read_public); #endif /* CONFIG_TCG_TPM2_HMAC */ =20 /** - * tpm_buf_append_name() - add a handle area to the buffer - * @chip: the TPM chip structure - * @buf: The buffer to be appended - * @handle: The handle to be appended - * @name: The name of the handle (may be NULL) + * tpm_buf_append_name() - Append a handle and store TPM name + * @chip: TPM chip to use. + * @buf: TPM buffer containing the TPM command in-transit. + * @handle: TPM handle to be appended. + * @name: TPM name of the handle + * @name_size: Size of the TPM name. * * In order to compute session HMACs, we need to know the names of the * objects pointed to by the handles. For most objects, this is simply @@ -236,15 +248,14 @@ static int tpm2_read_public(struct tpm_chip *chip, u3= 2 handle, void *name) * will be caused by an incorrect programming model and indicated by a * kernel message. * - * Ends the authorization session on failure. + * Returns zero on success. + * Returns -EIO when the authorization area state is malformed. */ int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf, - u32 handle, u8 *name) + u32 handle, u8 *name, u16 name_size) { #ifdef CONFIG_TCG_TPM2_HMAC - enum tpm2_mso_type mso =3D tpm2_handle_mso(handle); struct tpm2_auth *auth; - u16 name_size_alg; int slot; int ret; #endif @@ -269,36 +280,15 @@ int tpm_buf_append_name(struct tpm_chip *chip, struct= tpm_buf *buf, } tpm_buf_append_u32(buf, handle); auth->session +=3D 4; - - if (mso =3D=3D TPM2_MSO_PERSISTENT || - mso =3D=3D TPM2_MSO_VOLATILE || - mso =3D=3D TPM2_MSO_NVRAM) { - if (!name) { - ret =3D tpm2_read_public(chip, handle, auth->name[slot]); - if (ret < 0) - goto err; - - name_size_alg =3D ret; - } - } else { - if (name) { - dev_err(&chip->dev, "handle 0x%08x does not use a name\n", - handle); - ret =3D -EIO; - goto err; - } - } - - auth->name_h[slot] =3D handle; - if (name) - memcpy(auth->name[slot], name, name_size_alg); + memcpy(auth->name[slot], name, name_size); + auth->name_size_tbl[slot] =3D name_size; #endif return 0; =20 #ifdef CONFIG_TCG_TPM2_HMAC err: tpm2_end_auth_session(chip); - return tpm_ret_to_err(ret); + return ret; #endif } EXPORT_SYMBOL_GPL(tpm_buf_append_name); @@ -606,22 +596,8 @@ int tpm_buf_fill_hmac_session(struct tpm_chip *chip, s= truct tpm_buf *buf) attrs =3D chip->cc_attrs_tbl[i]; =20 handles =3D (attrs >> TPM2_CC_ATTR_CHANDLES) & GENMASK(2, 0); + offset_s +=3D handles * sizeof(u32); =20 - /* - * just check the names, it's easy to make mistakes. This - * would happen if someone added a handle via - * tpm_buf_append_u32() instead of tpm_buf_append_name() - */ - for (i =3D 0; i < handles; i++) { - u32 handle =3D tpm_buf_read_u32(buf, &offset_s); - - if (auth->name_h[i] !=3D handle) { - dev_err(&chip->dev, "invalid handle 0x%08x\n", handle); - ret =3D -EIO; - goto err; - } - } - /* point offset_s to the start of the sessions */ val =3D tpm_buf_read_u32(buf, &offset_s); /* point offset_p to the start of the parameters */ offset_p =3D offset_s + val; @@ -682,23 +658,8 @@ int tpm_buf_fill_hmac_session(struct tpm_chip *chip, s= truct tpm_buf *buf) /* ordinal is already BE */ sha256_update(&sctx, (u8 *)&head->ordinal, sizeof(head->ordinal)); /* add the handle names */ - for (i =3D 0; i < handles; i++) { - enum tpm2_mso_type mso =3D tpm2_handle_mso(auth->name_h[i]); - - if (mso =3D=3D TPM2_MSO_PERSISTENT || - mso =3D=3D TPM2_MSO_VOLATILE || - mso =3D=3D TPM2_MSO_NVRAM) { - ret =3D name_size(auth->name[i]); - if (ret < 0) - goto err; - - sha256_update(&sctx, auth->name[i], ret); - } else { - __be32 h =3D cpu_to_be32(auth->name_h[i]); - - sha256_update(&sctx, (u8 *)&h, 4); - } - } + for (i =3D 0; i < handles; i++) + sha256_update(&sctx, auth->name[i], auth->name_size_tbl[i]); if (offset_s !=3D tpm_buf_length(buf)) sha256_update(&sctx, &buf->data[offset_s], tpm_buf_length(buf) - offset_s); diff --git a/include/linux/tpm.h b/include/linux/tpm.h index 922a43ef23b5..9f684fc7ae04 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -543,7 +543,7 @@ static inline struct tpm2_auth *tpm2_chip_auth(struct t= pm_chip *chip) } =20 int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf, - u32 handle, u8 *name); + u32 handle, u8 *name, u16 name_size); void tpm_buf_append_hmac_session(struct tpm_chip *chip, struct tpm_buf *bu= f, u8 attributes, u8 *passphrase, int passphraselen); @@ -557,6 +557,7 @@ int tpm_buf_fill_hmac_session(struct tpm_chip *chip, st= ruct tpm_buf *buf); int tpm_buf_check_hmac_response(struct tpm_chip *chip, struct tpm_buf *buf, int rc); void tpm2_end_auth_session(struct tpm_chip *chip); +int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name); #else #include =20 @@ -580,6 +581,13 @@ static inline int tpm_buf_check_hmac_response(struct t= pm_chip *chip, { return rc; } + +static inline int tpm2_read_public(struct tpm_chip *chip, u32 handle, + void *name) +{ + memcpy(name, &handle, sizeof(u32)); + return sizeof(u32); +} #endif /* CONFIG_TCG_TPM2_HMAC */ =20 #endif diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trus= ted-keys/trusted_tpm2.c index 27424e1a4a63..63539b344ffb 100644 --- a/security/keys/trusted-keys/trusted_tpm2.c +++ b/security/keys/trusted-keys/trusted_tpm2.c @@ -203,7 +203,9 @@ int tpm2_seal_trusted(struct tpm_chip *chip, struct trusted_key_payload *payload, struct trusted_key_options *options) { + u8 parent_name[TPM2_MAX_NAME_SIZE]; off_t offset =3D TPM_HEADER_SIZE; + u16 parent_name_size; int blob_len =3D 0; int hash; u32 flags; @@ -220,6 +222,12 @@ int tpm2_seal_trusted(struct tpm_chip *chip, if (rc) return rc; =20 + rc =3D tpm2_read_public(chip, options->keyhandle, parent_name); + if (rc < 0) + goto out_put; + + parent_name_size =3D rc; + rc =3D tpm2_start_auth_session(chip); if (rc) goto out_put; @@ -234,7 +242,8 @@ int tpm2_seal_trusted(struct tpm_chip *chip, tpm_buf_init(buf, TPM_BUFSIZE); tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE); =20 - rc =3D tpm_buf_append_name(chip, buf, options->keyhandle, NULL); + rc =3D tpm_buf_append_name(chip, buf, options->keyhandle, parent_name, + parent_name_size); if (rc) goto out_put; =20 @@ -326,48 +335,38 @@ int tpm2_seal_trusted(struct tpm_chip *chip, } =20 /** - * tpm2_load_cmd() - execute a TPM2_Load command - * - * @chip: TPM chip to use - * @payload: the key data in clear and encrypted form - * @options: authentication values and other options - * @blob_handle: returned blob handle + * tpm2_load_cmd() - Execute TPM2_Load + * @chip: TPM chip to use. + * @payload: Key data in clear text. + * @options: Trusted key options. + * @parent_name: A cryptographic name, i.e. a TPMT_HA blob, of the + * parent key. + * @blob: The decoded payload for the key. + * @blob_handle: On success, will contain handle to the loaded keyedhash + * blob. * - * Return: 0 on success. - * -E2BIG on wrong payload size. - * -EPERM on tpm error status. - * < 0 error from tpm_send. + * Return -E2BIG when the blob size is too small for all the data. + * Returns tpm_transmit_cmd() error codes when either TPM2_Load fails. */ static int tpm2_load_cmd(struct tpm_chip *chip, struct trusted_key_payload *payload, struct trusted_key_options *options, + u8 *parent_name, + u16 parent_name_size, + const u8 *blob, u32 *blob_handle) { u8 *blob_ref __free(kfree) =3D NULL; unsigned int private_len; unsigned int public_len; unsigned int blob_len; - u8 *blob, *pub; + const u8 *pub; int rc; u32 attrs; =20 - rc =3D tpm2_key_decode(payload, options, &blob); - if (rc) { - /* old form */ - blob =3D payload->blob; - payload->old_format =3D 1; - } else { - /* Bind for cleanup: */ - blob_ref =3D blob; - } - - /* new format carries keyhandle but old format doesn't */ - if (!options->keyhandle) - return -EINVAL; - /* must be big enough for at least the two be16 size counts */ if (payload->blob_len < 4) - return -EINVAL; + return -E2BIG; =20 private_len =3D get_unaligned_be16(blob); =20 @@ -406,7 +405,8 @@ static int tpm2_load_cmd(struct tpm_chip *chip, tpm_buf_init(buf, TPM_BUFSIZE); tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD); =20 - rc =3D tpm_buf_append_name(chip, buf, options->keyhandle, NULL); + rc =3D tpm_buf_append_name(chip, buf, options->keyhandle, parent_name, + parent_name_size); if (rc) return rc; =20 @@ -434,20 +434,23 @@ static int tpm2_load_cmd(struct tpm_chip *chip, } =20 /** - * tpm2_unseal_cmd() - execute a TPM2_Unload command + * tpm2_unseal_cmd() - Execute TPM2_Unload * - * @chip: TPM chip to use - * @payload: the key data in clear and encrypted form - * @options: authentication values and other options - * @blob_handle: blob handle + * @chip: TPM chip to use + * @payload: Key data in clear text. + * @options: Trusted key options. + * @parent_name: A cryptographic name, i.e. a TPMT_HA blob, of the + * parent key. + * @blob_handle: Handle to the loaded keyedhash blob. * - * Return: 0 on success - * -EPERM on tpm error status - * < 0 error from tpm_send + * Return -E2BIG when the blob size is too small for all the data. + * Returns tpm_transmit_cmd() error codes when either TPM2_Load fails. */ static int tpm2_unseal_cmd(struct tpm_chip *chip, struct trusted_key_payload *payload, struct trusted_key_options *options, + u8 *parent_name, + u16 parent_name_size, u32 blob_handle) { u16 data_len; @@ -465,7 +468,8 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip, tpm_buf_init(buf, TPM_BUFSIZE); tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL); =20 - rc =3D tpm_buf_append_name(chip, buf, options->keyhandle, NULL); + rc =3D tpm_buf_append_name(chip, buf, options->keyhandle, parent_name, + parent_name_size); if (rc) return rc; =20 @@ -526,30 +530,60 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip, } =20 /** - * tpm2_unseal_trusted() - unseal the payload of a trusted key + * tpm2_unseal_trusted() - Unseal a trusted key + * @chip: TPM chip to use. + * @payload: Key data in clear text. + * @options: Trusted key options. * - * @chip: TPM chip to use - * @payload: the key data in clear and encrypted form - * @options: authentication values and other options - * - * Return: Same as with tpm_send. + * Return -E2BIG when the blob size is too small for all the data. + * Return -EINVAL when parent's key handle has not been set. + * Returns tpm_transmit_cmd() error codes when either TPM2_Load or TPM2_Un= seal + * fails. */ int tpm2_unseal_trusted(struct tpm_chip *chip, struct trusted_key_payload *payload, struct trusted_key_options *options) { + u8 *blob_ref __free(kfree) =3D NULL; + u8 parent_name[TPM2_MAX_NAME_SIZE]; + u16 parent_name_size; u32 blob_handle; + u8 *blob; int rc; =20 + /* + * Try to decode the provided blob as an ASN.1 blob. Assume that the + * blob is in the legacy format if decoding does not end successfully. + */ + rc =3D tpm2_key_decode(payload, options, &blob); + if (rc) { + blob =3D payload->blob; + payload->old_format =3D 1; + } else { + blob_ref =3D blob; + } + + if (!options->keyhandle) + return -EINVAL; + rc =3D tpm_try_get_ops(chip); if (rc) return rc; =20 - rc =3D tpm2_load_cmd(chip, payload, options, &blob_handle); + rc =3D tpm2_read_public(chip, options->keyhandle, parent_name); + if (rc < 0) + goto out; + + parent_name_size =3D rc; + + rc =3D tpm2_load_cmd(chip, payload, options, parent_name, + parent_name_size, blob, &blob_handle); if (rc) goto out; =20 - rc =3D tpm2_unseal_cmd(chip, payload, options, blob_handle); + rc =3D tpm2_unseal_cmd(chip, payload, options, parent_name, + parent_name_size, blob_handle); + tpm2_flush_context(chip, blob_handle); =20 out: --=20 2.52.0 From nobody Sat Feb 7 18:23:02 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 313FC22B5AC; Wed, 10 Dec 2025 14:40:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765377607; cv=none; b=CLe5Mp1HXKsWy/pcHgrXr+/fjcn9Hc7lu3xcuWLnVddC69Z5SMWzUCVccNTxdMocLGREfscHWKEV9P/RbKbfwVu9L0ETYNf9vvQ8dnZ5KTZKqK3r59vj3q4VulECWXSKS2UhGBkT9RBdZ3cc4Mr9TOXKSeND+iG8qX+3tE3cHiE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765377607; c=relaxed/simple; bh=j3sRY/5DqDHwhme3v+bOihyZBmakSNazCo3LEzMzmDU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=t+WRKmsdWKwU93ufDiQLpIYlTo7RpZa2lijhnpakFT5d5tGB5uYZETblvgKQnWDAzWY4ChjBo/IjzCY+anuoX6YGfJaqqxRJ+LDoIJGGkcKKv1OqGKtfa4/a2darYPBdrFS1zPTSazPY7X5OEJJksxVUBDlWlG1srQNl4O40p2E= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=JSqDof3E; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="JSqDof3E" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 73042C4CEF7; Wed, 10 Dec 2025 14:40:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1765377607; bh=j3sRY/5DqDHwhme3v+bOihyZBmakSNazCo3LEzMzmDU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JSqDof3ELnyqwtpyh2iCtrsVhQf4ZkaoPzAbP8LshSh2tVqcJ9N+5NKOOHGponhxA 5Zpipbnr4Va878yw+O6dEluexs4/+tF2JbCv3drBBQ/dTxc/5fj59k85w5YyZEerGU HZUs60yFkn2qAreALmSiwL21RXyjzEszShRS9lbhE9l0szMDQS9SU1eXi314XMKF6d xWBfJ8yA25RIvd607cf0G7sV7JTJVIQNTSdnG1CbEKGqNwx3ESxDgOI4ma97SwDvaz F1Wg/DmdVClUsJOeo4LwtwjN1iWFD8jT8M2nv2qqHEd3zachxN+D0vIerP/DPenxZr lbk/yv9wJ+LXQ== From: Jarkko Sakkinen To: linux-integrity@vger.kernel.org Cc: Jarkko Sakkinen , Peter Huewe , Jason Gunthorpe , David Howells , Paul Moore , James Morris , "Serge E. Hallyn" , linux-kernel@vger.kernel.org (open list), keyrings@vger.kernel.org (open list:KEYS/KEYRINGS), linux-security-module@vger.kernel.org (open list:SECURITY SUBSYSTEM) Subject: [PATCH v3 4/7] tpm2-sessions: Remove AUTH_MAX_NAMES Date: Wed, 10 Dec 2025 16:39:36 +0200 Message-ID: <20251210143940.264191-5-jarkko@kernel.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251210143940.264191-1-jarkko@kernel.org> References: <20251210143940.264191-1-jarkko@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" In all of the call sites only one session is ever append. Thus, reduce AUTH_MAX_NAMES, which leads into removing constant completely. Signed-off-by: Jarkko Sakkinen --- drivers/char/tpm/tpm2-sessions.c | 31 +++++++++++-------------------- 1 file changed, 11 insertions(+), 20 deletions(-) diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessi= ons.c index 0816a91134fc..62a200ae72d7 100644 --- a/drivers/char/tpm/tpm2-sessions.c +++ b/drivers/char/tpm/tpm2-sessions.c @@ -72,9 +72,6 @@ #include #include =20 -/* maximum number of names the TPM must remember for authorization */ -#define AUTH_MAX_NAMES 3 - #define AES_KEY_BYTES AES_KEYSIZE_128 #define AES_KEY_BITS (AES_KEY_BYTES*8) =20 @@ -136,8 +133,8 @@ struct tpm2_auth { * handle, but they are part of the session by name, which * we must compute and remember */ - u8 name[AUTH_MAX_NAMES][TPM2_MAX_NAME_SIZE]; - u16 name_size_tbl[AUTH_MAX_NAMES]; + u8 name[TPM2_MAX_NAME_SIZE]; + u16 name_size; }; =20 #ifdef CONFIG_TCG_TPM2_HMAC @@ -254,11 +251,14 @@ EXPORT_SYMBOL_GPL(tpm2_read_public); int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf, u32 handle, u8 *name, u16 name_size) { -#ifdef CONFIG_TCG_TPM2_HMAC struct tpm2_auth *auth; - int slot; int ret; -#endif + + if (tpm_buf_length(buf) !=3D TPM_HEADER_SIZE) { + dev_err(&chip->dev, "too many handles\n"); + ret =3D -EIO; + goto err; + } =20 if (!tpm2_chip_auth(chip)) { tpm_buf_append_handle(buf, handle); @@ -266,12 +266,6 @@ int tpm_buf_append_name(struct tpm_chip *chip, struct = tpm_buf *buf, } =20 #ifdef CONFIG_TCG_TPM2_HMAC - slot =3D (tpm_buf_length(buf) - TPM_HEADER_SIZE) / 4; - if (slot >=3D AUTH_MAX_NAMES) { - dev_err(&chip->dev, "too many handles\n"); - ret =3D -EIO; - goto err; - } auth =3D chip->auth; if (auth->session !=3D tpm_buf_length(buf)) { dev_err(&chip->dev, "session state malformed"); @@ -280,16 +274,14 @@ int tpm_buf_append_name(struct tpm_chip *chip, struct= tpm_buf *buf, } tpm_buf_append_u32(buf, handle); auth->session +=3D 4; - memcpy(auth->name[slot], name, name_size); - auth->name_size_tbl[slot] =3D name_size; + memcpy(auth->name, name, name_size); + auth->name_size =3D name_size; #endif return 0; =20 -#ifdef CONFIG_TCG_TPM2_HMAC err: tpm2_end_auth_session(chip); return ret; -#endif } EXPORT_SYMBOL_GPL(tpm_buf_append_name); =20 @@ -658,8 +650,7 @@ int tpm_buf_fill_hmac_session(struct tpm_chip *chip, st= ruct tpm_buf *buf) /* ordinal is already BE */ sha256_update(&sctx, (u8 *)&head->ordinal, sizeof(head->ordinal)); /* add the handle names */ - for (i =3D 0; i < handles; i++) - sha256_update(&sctx, auth->name[i], auth->name_size_tbl[i]); + sha256_update(&sctx, auth->name, auth->name_size); if (offset_s !=3D tpm_buf_length(buf)) sha256_update(&sctx, &buf->data[offset_s], tpm_buf_length(buf) - offset_s); --=20 2.52.0 From nobody Sat Feb 7 18:23:02 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6F3621FBEB0; Wed, 10 Dec 2025 14:40:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765377613; cv=none; b=Qw4qGqrhpVTvgG3Drbd0rEwvBCw8n9r9tE7BJmd/S7ETX1ofwm+XmGkyhdV89+Zf1c4UmftKKJ6l8le9OfKQUFzW8J1AUgWRIaF6fU9XsI7tkps0wnJYBkdsF5uBvXYO/HYzjSLNuIfKjfaBI2pI+gk/2nH8YxqjatkI6ILHs6E= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765377613; c=relaxed/simple; bh=FfDJCUK7lfUWywCaOcs8zoO2Q0y5xtmdcrVfwNUryIg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=lgfGSDa82v3DR+ggMnERlb1Pb4JC5bwOPxuwkt8zFCwB201b54yK4VFi0P2k7tyKqBLTvi9MuSKo8IPfHHwM9XsXhfV1fo3qUyXAxGg7CIZTSsXhqDfIF39rlyvN8vn1xfYFSYLgO9IILkXeufQOLcJVaIMEcVZoZdiAlTsVFu8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=L5yAk6Bt; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="L5yAk6Bt" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5ECF4C4CEF1; Wed, 10 Dec 2025 14:40:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1765377613; bh=FfDJCUK7lfUWywCaOcs8zoO2Q0y5xtmdcrVfwNUryIg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=L5yAk6BtGPVocue9n93+9wR/UcAg7j7yS43G6xnbHgoQuv2/On3JlCHlMcd8ixgmQ 8O0IyrZzx0fn1fEemfakEiqef4/mI5cwpIZBbbC/GsFyZ1FFPEcAfKfKWMIWbhzjHP 6v4weyhDYm049TIs4N+/8Mnu7FXKIbpX9VSUq1yE89RfkCSBrOL2qjVk+iVuhlfwIX EkBsQ57JjdPD5a/zVHCJ0fHnZxW2pkkHCS8sA+dXSsfVhOrR3ZqqlQo6z1VPEn76Xv VAklQETt9O5eoaX7YxZWpb3ZJF5NpOFCyDzd++xCm3VjcKnt7b9kGs6/w9jsdWias/ /8WQO3Jyu+z5A== From: Jarkko Sakkinen To: linux-integrity@vger.kernel.org Cc: Jarkko Sakkinen , Peter Huewe , Jason Gunthorpe , David Howells , Paul Moore , James Morris , "Serge E. Hallyn" , linux-kernel@vger.kernel.org (open list), keyrings@vger.kernel.org (open list:KEYS/KEYRINGS), linux-security-module@vger.kernel.org (open list:SECURITY SUBSYSTEM) Subject: [PATCH v3 5/7] tpm-buf: Remove tpm_buf_append_handle Date: Wed, 10 Dec 2025 16:39:37 +0200 Message-ID: <20251210143940.264191-6-jarkko@kernel.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251210143940.264191-1-jarkko@kernel.org> References: <20251210143940.264191-1-jarkko@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Since the number of handles is fixed to a single handle, eliminate all uses of buf->handles and deduce values during compile-time. Signed-off-by: Jarkko Sakkinen --- v2: - Streamline the code change and remove dead code. --- drivers/char/tpm/tpm-buf.c | 25 ------------------------- drivers/char/tpm/tpm2-cmd.c | 6 ++---- drivers/char/tpm/tpm2-sessions.c | 14 ++------------ include/linux/tpm.h | 2 -- 4 files changed, 4 insertions(+), 43 deletions(-) diff --git a/drivers/char/tpm/tpm-buf.c b/drivers/char/tpm/tpm-buf.c index 73be8a87b472..752c69b8a4f5 100644 --- a/drivers/char/tpm/tpm-buf.c +++ b/drivers/char/tpm/tpm-buf.c @@ -40,7 +40,6 @@ static void __tpm_buf_reset(struct tpm_buf *buf, u16 buf_= size, u16 tag, u32 ordi buf->flags =3D 0; buf->length =3D sizeof(*head); buf->capacity =3D buf_size - sizeof(*buf); - buf->handles =3D 0; head->tag =3D cpu_to_be16(tag); head->length =3D cpu_to_be32(sizeof(*head)); head->ordinal =3D cpu_to_be32(ordinal); @@ -56,7 +55,6 @@ static void __tpm_buf_reset_sized(struct tpm_buf *buf, u1= 6 buf_size) buf->flags =3D TPM_BUF_TPM2B; buf->length =3D 2; buf->capacity =3D buf_size - sizeof(*buf); - buf->handles =3D 0; buf->data[0] =3D 0; buf->data[1] =3D 0; } @@ -177,29 +175,6 @@ void tpm_buf_append_u32(struct tpm_buf *buf, const u32= value) } EXPORT_SYMBOL_GPL(tpm_buf_append_u32); =20 -/** - * tpm_buf_append_handle() - Add a handle - * @buf: &tpm_buf instance - * @handle: a TPM object handle - * - * Add a handle to the buffer, and increase the count tracking the number = of - * handles in the command buffer. Works only for command buffers. - */ -void tpm_buf_append_handle(struct tpm_buf *buf, u32 handle) -{ - if (buf->flags & TPM_BUF_INVALID) - return; - - if (buf->flags & TPM_BUF_TPM2B) { - WARN(1, "tpm-buf: invalid type: TPM2B\n"); - buf->flags |=3D TPM_BUF_INVALID; - return; - } - - tpm_buf_append_u32(buf, handle); - buf->handles++; -} - /** * tpm_buf_read() - Read from a TPM buffer * @buf: &tpm_buf instance diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c index 436ee82620e4..bc50d6b734cf 100644 --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -205,7 +205,7 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, return rc; tpm_buf_append_hmac_session(chip, buf, 0, NULL, 0); } else { - tpm_buf_append_handle(buf, pcr_idx); + tpm_buf_append_u32(buf, pcr_idx); tpm_buf_append_auth(chip, buf, NULL, 0); } =20 @@ -281,10 +281,8 @@ int tpm2_get_random(struct tpm_chip *chip, u8 *dest, s= ize_t max) TPM2_SA_CONTINUE_SESSION, NULL, 0); } else { - offset =3D buf->handles * 4 + TPM_HEADER_SIZE; head =3D (struct tpm_header *)buf->data; - if (tpm_buf_length(buf) =3D=3D offset) - head->tag =3D cpu_to_be16(TPM2_ST_NO_SESSIONS); + head->tag =3D cpu_to_be16(TPM2_ST_NO_SESSIONS); } tpm_buf_append_u16(buf, num_bytes); err =3D tpm_buf_fill_hmac_session(chip, buf); diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessi= ons.c index 62a200ae72d7..f2b8ca893e15 100644 --- a/drivers/char/tpm/tpm2-sessions.c +++ b/drivers/char/tpm/tpm2-sessions.c @@ -261,7 +261,7 @@ int tpm_buf_append_name(struct tpm_chip *chip, struct t= pm_buf *buf, } =20 if (!tpm2_chip_auth(chip)) { - tpm_buf_append_handle(buf, handle); + tpm_buf_append_u32(buf, handle); return 0; } =20 @@ -288,17 +288,7 @@ EXPORT_SYMBOL_GPL(tpm_buf_append_name); void tpm_buf_append_auth(struct tpm_chip *chip, struct tpm_buf *buf, u8 *passphrase, int passphrase_len) { - /* offset tells us where the sessions area begins */ - int offset =3D buf->handles * 4 + TPM_HEADER_SIZE; - u32 len =3D 9 + passphrase_len; - - if (tpm_buf_length(buf) !=3D offset) { - /* not the first session so update the existing length */ - len +=3D get_unaligned_be32(&buf->data[offset]); - put_unaligned_be32(len, &buf->data[offset]); - } else { - tpm_buf_append_u32(buf, len); - } + tpm_buf_append_u32(buf, 9 + passphrase_len); /* auth handle */ tpm_buf_append_u32(buf, TPM2_RS_PW); /* nonce */ diff --git a/include/linux/tpm.h b/include/linux/tpm.h index 9f684fc7ae04..e68995df8796 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -395,7 +395,6 @@ enum tpm_buf_flags { */ struct tpm_buf { u8 flags; - u8 handles; u16 length; u16 capacity; u8 data[]; @@ -441,7 +440,6 @@ void tpm_buf_append_u32(struct tpm_buf *buf, const u32 = value); u8 tpm_buf_read_u8(struct tpm_buf *buf, off_t *offset); u16 tpm_buf_read_u16(struct tpm_buf *buf, off_t *offset); u32 tpm_buf_read_u32(struct tpm_buf *buf, off_t *offset); -void tpm_buf_append_handle(struct tpm_buf *buf, u32 handle); =20 /* * Check if TPM device is in the firmware upgrade mode. --=20 2.52.0 From nobody Sat Feb 7 18:23:02 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5344A1FBEB0; 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dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Ek1rwzUh" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 995FCC4CEF1; Wed, 10 Dec 2025 14:40:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1765377618; bh=WLQk3Xede69EtFXrvulM+AC7dDssR/HOPcpLT5B8Px0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ek1rwzUhzf0MNDBNuOycG+XAt5Mwmxt3xH3oMbjUg8OuF2yR4UwH1UN2axzpoYZBz hqZJisUax45jWoS+WVfMVJtNhRNZxLr8AVeNY3JAanHFylQNRUGWj7HsCOI+Q1Ruuv 6xBPk9DnI0lFKcNgeyBbJL4uf7Xl5f7Zi8XibkmbKw59n3iLJuatdzgn5zYgcrIj0i 9b2cyI7tvcRtS6LOhrp2s1Tv69Cmlg0XFMcDAua5yJUTnGj7+L0S3nWYi+PIsjvM4E /cvmyOTD2gFKz8Ng8OUPhmcL/ID1vpW59nKgDfLMZPKf/nvqsnZvLkOI15zMSuqhXx lydu5K/mZRb2w== From: Jarkko Sakkinen To: linux-integrity@vger.kernel.org Cc: Jarkko Sakkinen , Peter Huewe , Jason Gunthorpe , David Howells , Paul Moore , James Morris , "Serge E. Hallyn" , linux-kernel@vger.kernel.org (open list), keyrings@vger.kernel.org (open list:KEYS/KEYRINGS), linux-security-module@vger.kernel.org (open list:SECURITY SUBSYSTEM) Subject: [PATCH v3 6/7] tpm: Orchestrate TPM commands in tpm_get_random() Date: Wed, 10 Dec 2025 16:39:38 +0200 Message-ID: <20251210143940.264191-7-jarkko@kernel.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251210143940.264191-1-jarkko@kernel.org> References: <20251210143940.264191-1-jarkko@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" tpm1_get_random() and tpm2_get_random() contain duplicate orchestration code. Consolidate orchestration to tpm_get_random(). Signed-off-by: Jarkko Sakkinen --- drivers/char/tpm/tpm-interface.c | 165 ++++++++++++++++++++++++++++--- drivers/char/tpm/tpm.h | 2 - drivers/char/tpm/tpm1-cmd.c | 62 ------------ drivers/char/tpm/tpm2-cmd.c | 95 ------------------ 4 files changed, 154 insertions(+), 170 deletions(-) diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interf= ace.c index f745a098908b..ab52a1cb0a78 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -26,7 +26,7 @@ #include #include #include - +#include #include "tpm.h" =20 /* @@ -486,19 +486,143 @@ int tpm_pm_resume(struct device *dev) } EXPORT_SYMBOL_GPL(tpm_pm_resume); =20 +struct tpm1_get_random_out { + __be32 rng_data_len; + u8 rng_data[TPM_MAX_RNG_DATA]; +} __packed; + +static int tpm1_get_random(struct tpm_chip *chip, u8 *out, size_t max) +{ + struct tpm1_get_random_out *resp; + u32 recd; + int rc; + + if (!out || !max || max > TPM_MAX_RNG_DATA) + return -EINVAL; + + struct tpm_buf *buf __free(kfree) =3D kzalloc(TPM_BUFSIZE, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + tpm_buf_init(buf, TPM_BUFSIZE); + tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GETRANDOM); + tpm_buf_append_u32(buf, max); + + rc =3D tpm_transmit_cmd(chip, buf, sizeof(resp->rng_data_len), "TPM_GetRa= ndom"); + if (rc) { + if (rc > 0) + rc =3D -EIO; + return rc; + } + + resp =3D (struct tpm1_get_random_out *)&buf->data[TPM_HEADER_SIZE]; + + recd =3D be32_to_cpu(resp->rng_data_len); + if (recd > max) + return -EIO; + + if (buf->length < TPM_HEADER_SIZE + sizeof(resp->rng_data_len) + recd) + return -EIO; + + memcpy(out, resp->rng_data, recd); + return recd; +} + +struct tpm2_get_random_out { + __be16 size; + u8 buffer[TPM_MAX_RNG_DATA]; +} __packed; + +static int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max) +{ + struct tpm2_get_random_out *resp; + struct tpm_header *head; + off_t offset; + u32 recd; + int ret; + + if (!out || !max || max > TPM_MAX_RNG_DATA) + return -EINVAL; + + struct tpm_buf *buf __free(kfree) =3D kzalloc(TPM_BUFSIZE, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + tpm_buf_init(buf, TPM_BUFSIZE); + tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_GET_RANDOM); + if (tpm2_chip_auth(chip)) { + tpm_buf_append_hmac_session(chip, buf, + TPM2_SA_ENCRYPT | TPM2_SA_CONTINUE_SESSION, + NULL, 0); + } else { + head =3D (struct tpm_header *)buf->data; + head->tag =3D cpu_to_be16(TPM2_ST_NO_SESSIONS); + } + tpm_buf_append_u16(buf, max); + + ret =3D tpm_buf_fill_hmac_session(chip, buf); + if (ret) + return ret; + + ret =3D tpm_transmit_cmd(chip, buf, offsetof(struct tpm2_get_random_out, = buffer), + "TPM2_GetRandom"); + + ret =3D tpm_buf_check_hmac_response(chip, buf, ret); + if (ret) { + if (ret > 0) + ret =3D -EIO; + + goto out; + } + + head =3D (struct tpm_header *)buf->data; + offset =3D TPM_HEADER_SIZE; + + /* Skip the parameter size field: */ + if (be16_to_cpu(head->tag) =3D=3D TPM2_ST_SESSIONS) + offset +=3D 4; + + resp =3D (struct tpm2_get_random_out *)&buf->data[offset]; + recd =3D min_t(u32, be16_to_cpu(resp->size), max); + + if (tpm_buf_length(buf) < + TPM_HEADER_SIZE + offsetof(struct tpm2_get_random_out, buffer) + recd= ) { + ret =3D -EIO; + goto out; + } + + memcpy(out, resp->buffer, recd); + return recd; + +out: + tpm2_end_auth_session(chip); + return ret; +} + /** - * tpm_get_random() - get random bytes from the TPM's RNG - * @chip: a &struct tpm_chip instance, %NULL for the default chip - * @out: destination buffer for the random bytes - * @max: the max number of bytes to write to @out + * tpm_get_random() - Get random bytes from the TPM's RNG + * @chip: A &tpm_chip instance. Whenset to %NULL, the default chip is used. + * @out: Destination buffer for the acquired random bytes. + * @max: The maximum number of bytes to write to @out. * - * Return: number of random bytes read or a negative error value. + * Iterates pulling more bytes from TPM up until all of the @max bytes hav= e been + * received. + * + * Returns the number of random bytes read on success. + * Returns -EINVAL when @out is NULL, or @max is not between zero and + * %TPM_MAX_RNG_DATA. + * Returns tpm_transmit_cmd() error codes when the TPM command results an + * error. */ int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max) { + u32 num_bytes =3D max; + u8 *out_ptr =3D out; + int retries =3D 5; + int total =3D 0; int rc; =20 - if (!out || max > TPM_MAX_RNG_DATA) + if (!out || !max || max > TPM_MAX_RNG_DATA) return -EINVAL; =20 if (!chip) @@ -508,11 +632,30 @@ int tpm_get_random(struct tpm_chip *chip, u8 *out, si= ze_t max) if (rc) return rc; =20 - if (chip->flags & TPM_CHIP_FLAG_TPM2) - rc =3D tpm2_get_random(chip, out, max); - else - rc =3D tpm1_get_random(chip, out, max); + if (chip->flags & TPM_CHIP_FLAG_TPM2) { + rc =3D tpm2_start_auth_session(chip); + if (rc) + return rc; + } + + do { + if (chip->flags & TPM_CHIP_FLAG_TPM2) + rc =3D tpm2_get_random(chip, out_ptr, num_bytes); + else + rc =3D tpm1_get_random(chip, out_ptr, num_bytes); + + if (rc < 0) + goto err; + + out_ptr +=3D rc; + total +=3D rc; + num_bytes -=3D rc; + } while (retries-- && total < max); + + tpm_put_ops(chip); + return total ? total : -EIO; =20 +err: tpm_put_ops(chip); return rc; } diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index 5395927c62fc..c4bbd8f04605 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -250,7 +250,6 @@ int tpm1_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,= const u8 *hash, int tpm1_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf); ssize_t tpm1_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap, const char *desc, size_t min_cap_length); -int tpm1_get_random(struct tpm_chip *chip, u8 *out, size_t max); int tpm1_get_pcr_allocation(struct tpm_chip *chip); unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal= ); int tpm_pm_suspend(struct device *dev); @@ -290,7 +289,6 @@ int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx, struct tpm_digest *digest, u16 *digest_size_ptr); int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, struct tpm_digest *digests); -int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max); ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id, u32 *value, const char *desc); =20 diff --git a/drivers/char/tpm/tpm1-cmd.c b/drivers/char/tpm/tpm1-cmd.c index 11090053ef54..d8f16e66666b 100644 --- a/drivers/char/tpm/tpm1-cmd.c +++ b/drivers/char/tpm/tpm1-cmd.c @@ -502,68 +502,6 @@ ssize_t tpm1_getcap(struct tpm_chip *chip, u32 subcap_= id, cap_t *cap, } EXPORT_SYMBOL_GPL(tpm1_getcap); =20 -#define TPM_ORD_GET_RANDOM 70 -struct tpm1_get_random_out { - __be32 rng_data_len; - u8 rng_data[TPM_MAX_RNG_DATA]; -} __packed; - -/** - * tpm1_get_random() - get random bytes from the TPM's RNG - * @chip: a &struct tpm_chip instance - * @dest: destination buffer for the random bytes - * @max: the maximum number of bytes to write to @dest - * - * Return: - * * number of bytes read - * * -errno (positive TPM return codes are masked to -EIO) - */ -int tpm1_get_random(struct tpm_chip *chip, u8 *dest, size_t max) -{ - struct tpm1_get_random_out *out; - u32 num_bytes =3D min_t(u32, max, TPM_MAX_RNG_DATA); - u32 total =3D 0; - int retries =3D 5; - u32 recd; - int rc; - - struct tpm_buf *buf __free(kfree) =3D kzalloc(TPM_BUFSIZE, GFP_KERNEL); - if (!buf) - return -ENOMEM; - - tpm_buf_init(buf, TPM_BUFSIZE); - do { - tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GET_RANDOM); - tpm_buf_append_u32(buf, num_bytes); - - rc =3D tpm_transmit_cmd(chip, buf, sizeof(out->rng_data_len), "TPM_GetRa= ndom"); - if (rc) { - if (rc > 0) - rc =3D -EIO; - return rc; - } - - out =3D (struct tpm1_get_random_out *)&buf->data[TPM_HEADER_SIZE]; - - recd =3D be32_to_cpu(out->rng_data_len); - if (recd > num_bytes) - return -EFAULT; - - if (buf->length < TPM_HEADER_SIZE + - sizeof(out->rng_data_len) + recd) - return -EFAULT; - - memcpy(dest, out->rng_data, recd); - - dest +=3D recd; - total +=3D recd; - num_bytes -=3D recd; - } while (retries-- && total < max); - - rc =3D total ? (int)total : -EIO; - return rc; -} - #define TPM_ORD_PCRREAD 21 int tpm1_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf) { diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c index bc50d6b734cf..f066efb54a2c 100644 --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -233,101 +233,6 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_id= x, return rc; } =20 -struct tpm2_get_random_out { - __be16 size; - u8 buffer[TPM_MAX_RNG_DATA]; -} __packed; - -/** - * tpm2_get_random() - get random bytes from the TPM RNG - * - * @chip: a &tpm_chip instance - * @dest: destination buffer - * @max: the max number of random bytes to pull - * - * Return: - * size of the buffer on success, - * -errno otherwise (positive TPM return codes are masked to -EIO) - */ -int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max) -{ - struct tpm2_get_random_out *out; - struct tpm_header *head; - u32 recd; - u32 num_bytes =3D max; - int err; - int total =3D 0; - int retries =3D 5; - u8 *dest_ptr =3D dest; - off_t offset; - - if (!num_bytes || max > TPM_MAX_RNG_DATA) - return -EINVAL; - - struct tpm_buf *buf __free(kfree) =3D kzalloc(TPM_BUFSIZE, GFP_KERNEL); - if (!buf) - return -ENOMEM; - - err =3D tpm2_start_auth_session(chip); - if (err) - return err; - - tpm_buf_init(buf, TPM_BUFSIZE); - do { - tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_GET_RANDOM); - if (tpm2_chip_auth(chip)) { - tpm_buf_append_hmac_session(chip, buf, - TPM2_SA_ENCRYPT | - TPM2_SA_CONTINUE_SESSION, - NULL, 0); - } else { - head =3D (struct tpm_header *)buf->data; - head->tag =3D cpu_to_be16(TPM2_ST_NO_SESSIONS); - } - tpm_buf_append_u16(buf, num_bytes); - err =3D tpm_buf_fill_hmac_session(chip, buf); - if (err) - return err; - - err =3D tpm_transmit_cmd(chip, buf, - offsetof(struct tpm2_get_random_out, - buffer), - "TPM2_GetRandom"); - err =3D tpm_buf_check_hmac_response(chip, buf, err); - if (err) { - if (err > 0) - err =3D -EIO; - goto out; - } - - head =3D (struct tpm_header *)buf->data; - offset =3D TPM_HEADER_SIZE; - /* Skip the parameter size field: */ - if (be16_to_cpu(head->tag) =3D=3D TPM2_ST_SESSIONS) - offset +=3D 4; - - out =3D (struct tpm2_get_random_out *)&buf->data[offset]; - recd =3D min_t(u32, be16_to_cpu(out->size), num_bytes); - if (tpm_buf_length(buf) < - TPM_HEADER_SIZE + - offsetof(struct tpm2_get_random_out, buffer) + - recd) { - err =3D -EFAULT; - goto out; - } - memcpy(dest_ptr, out->buffer, recd); - - dest_ptr +=3D recd; - total +=3D recd; - num_bytes -=3D recd; - } while (retries-- && total < max); - - return total ? total : -EIO; -out: - tpm2_end_auth_session(chip); - return err; -} - /** * tpm2_flush_context() - execute a TPM2_FlushContext command * @chip: TPM chip to use --=20 2.52.0 From nobody Sat Feb 7 18:23:02 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C994818787A; Wed, 10 Dec 2025 14:40:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765377623; cv=none; b=tG1IS+xzLlv1ez2osIyIOKfmjMY4GPraQo+JGAMXPmjNX1HBn0s0Gs5mEPpVxa/DXpXTarCFWU0KU1VVD2Q/xSNCHWog6C2Q2gh92f4jtXXKU46bVfvwOjOPTAotb8pRHuaJegZOP42YiUn8kNxN8SoRb14dVpK5eBrDwtNGMKk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765377623; c=relaxed/simple; bh=FQ+qWhMfMoahdE00Fr6dXweIZfekA7MYZG6DDTqt6mI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=LcBd2Mni/+M7BvCYUWsK8CUajrYVsCHQXzk/c3N7GdoOdMHBskwTzsEO3KAXYOPafCf1n3q6p1XLU7XvvfQZlPitKWu8xtvAhDE8C6xoEecocATDn7R5HcXqeBL98Ceud5QzCN1fivw9t7uhyPbOrIdyL62y+sy82+uMKYoqzTQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=iiw18lkT; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="iiw18lkT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D0E14C4CEF1; Wed, 10 Dec 2025 14:40:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1765377623; bh=FQ+qWhMfMoahdE00Fr6dXweIZfekA7MYZG6DDTqt6mI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iiw18lkTlOjuolYETIXFi6zexb1ECE9BIigC8smYwx8B3W9hOx72zcnmkccjSc6Go Q8DZpH1U+1WpjtWQoi47LU9oJ/uVCd2tk2cumaGCfxbvXAJ9jg1iDuXML1kvyfHs4Q RhcKV37PUSSMJGuRcczno5aKtDYPcRjY/0kXccla86oXty49EPCl0Luk2QhzvRFUPA jYr8rPobbNMBI5GmOYE9VH1widZq5/YELS6ZjXz7naO6JxnZPNbGEIJK2+2kTYeb5k 2aLyZOELt/UQwSkQ6do7NKM86E8m5UcyBKwQWKngWOE9MKVaDlxvXKu7NwYK7E4yk1 mLwRmwrN1VhYg== From: Jarkko Sakkinen To: linux-integrity@vger.kernel.org Cc: Jarkko Sakkinen , "David S. Miller" , Herbert Xu , Peter Huewe , Jason Gunthorpe , David Howells , Paul Moore , James Morris , "Serge E. Hallyn" , James Bottomley , Mimi Zohar , linux-kernel@vger.kernel.org (open list), keyrings@vger.kernel.org (open list:KEYS/KEYRINGS), linux-security-module@vger.kernel.org (open list:SECURITY SUBSYSTEM) Subject: [PATCH v3 7/7] tpm: Send only one TPM command per hwrng request Date: Wed, 10 Dec 2025 16:39:39 +0200 Message-ID: <20251210143940.264191-8-jarkko@kernel.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251210143940.264191-1-jarkko@kernel.org> References: <20251210143940.264191-1-jarkko@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" hwrng framework does not have a enforce that all bytes requested need to be read. By enforcing such a requirement internally, TPM driver can cause unpredicatability in latency, as a single tpm_get_random() call can result multiple TPM commands. Especially, when TCG_TPM2_HMAC is enabled, roundtrips with the TPM should be capped to exactly one. Add a @wait parameter to enforce this behavior and set it to true at the call sites TPM 1.2 keys. At the call sites of hwrng, set @wait to false. Cc: David S. Miller Cc: Herbert Xu Signed-off-by: Jarkko Sakkinen --- drivers/char/tpm/tpm-chip.c | 2 +- drivers/char/tpm/tpm-interface.c | 11 +++++++++-- include/linux/tpm.h | 2 +- security/keys/trusted-keys/trusted_tpm1.c | 8 ++++---- 4 files changed, 15 insertions(+), 8 deletions(-) diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c index 082b910ddf0d..8fca4373e2df 100644 --- a/drivers/char/tpm/tpm-chip.c +++ b/drivers/char/tpm/tpm-chip.c @@ -494,7 +494,7 @@ static int tpm_hwrng_read(struct hwrng *rng, void *data= , size_t max, bool wait) { struct tpm_chip *chip =3D container_of(rng, struct tpm_chip, hwrng); =20 - return tpm_get_random(chip, data, max); + return tpm_get_random(chip, data, max, false); } =20 static bool tpm_is_hwrng_enabled(struct tpm_chip *chip) diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interf= ace.c index ab52a1cb0a78..5cc2bbabd57a 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -604,9 +604,11 @@ static int tpm2_get_random(struct tpm_chip *chip, u8 *= out, size_t max) * @chip: A &tpm_chip instance. Whenset to %NULL, the default chip is used. * @out: Destination buffer for the acquired random bytes. * @max: The maximum number of bytes to write to @out. + * @wait: Set to true when all of the @max bytes need to be acquired. * * Iterates pulling more bytes from TPM up until all of the @max bytes hav= e been - * received. + * received, when @wait it sets true. Otherwise, the queries for @max byte= s from + * TPM exactly once, and returns the bytes that were received. * * Returns the number of random bytes read on success. * Returns -EINVAL when @out is NULL, or @max is not between zero and @@ -614,7 +616,7 @@ static int tpm2_get_random(struct tpm_chip *chip, u8 *o= ut, size_t max) * Returns tpm_transmit_cmd() error codes when the TPM command results an * error. */ -int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max) +int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max, bool wait) { u32 num_bytes =3D max; u8 *out_ptr =3D out; @@ -647,6 +649,11 @@ int tpm_get_random(struct tpm_chip *chip, u8 *out, siz= e_t max) if (rc < 0) goto err; =20 + if (!wait) { + total =3D rc; + break; + } + out_ptr +=3D rc; total +=3D rc; num_bytes -=3D rc; diff --git a/include/linux/tpm.h b/include/linux/tpm.h index e68995df8796..177833d6b965 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -485,7 +485,7 @@ extern int tpm_pcr_read(struct tpm_chip *chip, u32 pcr_= idx, struct tpm_digest *digest); extern int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, struct tpm_digest *digests); -extern int tpm_get_random(struct tpm_chip *chip, u8 *data, size_t max); +int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max, bool wait); extern struct tpm_chip *tpm_default_chip(void); void tpm2_flush_context(struct tpm_chip *chip, u32 handle); int tpm2_find_hash_alg(unsigned int crypto_id); diff --git a/security/keys/trusted-keys/trusted_tpm1.c b/security/keys/trus= ted-keys/trusted_tpm1.c index 759c1ecb0435..f36f6a0b533f 100644 --- a/security/keys/trusted-keys/trusted_tpm1.c +++ b/security/keys/trusted-keys/trusted_tpm1.c @@ -361,7 +361,7 @@ static int osap(struct tpm_buf *tb, struct osapsess *s, unsigned char ononce[TPM_NONCE_SIZE]; int ret; =20 - ret =3D tpm_get_random(chip, ononce, TPM_NONCE_SIZE); + ret =3D tpm_get_random(chip, ononce, TPM_NONCE_SIZE, true); if (ret < 0) return ret; =20 @@ -454,7 +454,7 @@ static int tpm_seal(struct tpm_buf *tb, uint16_t keytyp= e, memcpy(td->xorwork + SHA1_DIGEST_SIZE, sess.enonce, SHA1_DIGEST_SIZE); sha1(td->xorwork, SHA1_DIGEST_SIZE * 2, td->xorhash); =20 - ret =3D tpm_get_random(chip, td->nonceodd, TPM_NONCE_SIZE); + ret =3D tpm_get_random(chip, td->nonceodd, TPM_NONCE_SIZE, true); if (ret < 0) goto out; =20 @@ -565,7 +565,7 @@ static int tpm_unseal(struct tpm_buf *tb, } =20 ordinal =3D htonl(TPM_ORD_UNSEAL); - ret =3D tpm_get_random(chip, nonceodd, TPM_NONCE_SIZE); + ret =3D tpm_get_random(chip, nonceodd, TPM_NONCE_SIZE, true); if (ret < 0) return ret; =20 @@ -938,7 +938,7 @@ static int trusted_tpm_unseal(struct trusted_key_payloa= d *p, char *datablob) =20 static int trusted_tpm_get_random(unsigned char *key, size_t key_len) { - return tpm_get_random(chip, key, key_len); + return tpm_get_random(chip, key, key_len, true); } =20 static int __init init_digests(void) --=20 2.52.0