From nobody Tue Dec 16 14:35:47 2025 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 9DFF71DF75B; Sun, 14 Dec 2025 15:38:38 +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=1765726718; cv=none; b=erXc3pmSrjHBw0RwN4L6MNctcENo04qOHM8tSNt0wtsTYtqXn33hRnyjUDOguUlPYMT5kfu8SD0g4rxM2Vv/jt09ABpMuT64PibZIxxC6yY1jDoWPOscRO1HIpt2KRiTz40qMKmrN6X9fc7Hy8PjHPPk6mr0PHsLFrgISjEsscc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765726718; c=relaxed/simple; bh=vV1b4wuozXw9wp/4XVuxm/8LB4QO8nZCo2R/jDl7Daw=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=mqGpNkY+hKJX2pJbsF/LVQlcPaqzEpzvp9fx9gaFILsjmbHF2kgw/3tW9PLyEwGAeA26IMPOOSen+i1rs5484w5xUduRobxO4KiwdS1bnwjL9yVrjUUTwKnjVKx8ZJ7d6cLLdT8/XG/WFlxCmNyri62uWwE/YOQsBsDIfLgHlN4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ldRtu7cZ; 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="ldRtu7cZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C1E86C4CEF1; Sun, 14 Dec 2025 15:38:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1765726718; bh=vV1b4wuozXw9wp/4XVuxm/8LB4QO8nZCo2R/jDl7Daw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ldRtu7cZ1I1TY2yg0du2vX8VX/xvYos5teP5cxzHIlumb/nrbBQT9gHhgiPisjKJ7 0MAkZF4vA37rcH+RHHcNME0z4WawcU6EOPO6mZFoBkFgG9CaoSx7BnMvF0bqYeNrtO rkHYwtXk2uNr8bVGAM/1lBwZUyAyte+1yrW84VelFrxgsy5ZM9kg1q/Dai9mwq2KeH fSZRddA3BMoFddEil3Q89TcYX0ioAW1+Rg4uLq6zYbi2/i/7V/Fec6PkbCst/Rn2vl OPVDlIi7K8DR+etBXzcES8tPi99rwYqynefDwO3n+F2qiDT/lZ/EZ02VRRg23/jc74 Q0s/C2ng6bcxQ== From: Jarkko Sakkinen To: linux-integrity@vger.kernel.org Cc: Ross Philipson , 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 v6 04/11] KEYS: trusted: Re-orchestrate tpm2_read_public() calls Date: Sun, 14 Dec 2025 17:38:01 +0200 Message-Id: <20251214153808.73831-5-jarkko@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20251214153808.73831-1-jarkko@kernel.org> References: <20251214153808.73831-1-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 3a77be7ebf4a..1f561ad3bdcf 100644 --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -202,7 +202,8 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, } =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) { tpm_buf_destroy(&buf); return rc; diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessi= ons.c index 525b8622d1c3..3bc3c31cf512 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; @@ -219,14 +229,16 @@ 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 @@ -243,15 +255,14 @@ 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 @@ -276,36 +287,15 @@ 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); @@ -613,22 +603,8 @@ 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; @@ -689,23 +665,8 @@ 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 e10f2096eae7..72610f1aa402 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 3666e3e48eab..3de84b30b655 100644 --- a/security/keys/trusted-keys/trusted_tpm2.c +++ b/security/keys/trusted-keys/trusted_tpm2.c @@ -203,8 +203,10 @@ 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; struct tpm_buf buf, sized; + u16 parent_name_size; int blob_len =3D 0; int hash; u32 flags; @@ -221,6 +223,12 @@ 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; @@ -238,7 +246,8 @@ int tpm2_seal_trusted(struct tpm_chip *chip, goto out_put; } =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; =20 @@ -325,21 +334,25 @@ 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; @@ -347,27 +360,13 @@ static int tpm2_load_cmd(struct tpm_chip *chip, 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 @@ -403,7 +402,8 @@ static int tpm2_load_cmd(struct tpm_chip *chip, return rc; } =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; =20 @@ -435,20 +435,23 @@ 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) { struct tpm_buf buf; @@ -466,7 +469,8 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip, return rc; } =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; =20 @@ -539,30 +543,60 @@ 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 2.39.5