From patchwork Tue Oct 30 15:47:09 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 10661165 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 967ED13B5 for ; Tue, 30 Oct 2018 15:51:09 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 861022A80D for ; Tue, 30 Oct 2018 15:51:09 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 837CF2A7FD; Tue, 30 Oct 2018 15:51:09 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 077B62A7D6 for ; Tue, 30 Oct 2018 15:51:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727543AbeJaApH (ORCPT ); Tue, 30 Oct 2018 20:45:07 -0400 Received: from lhrrgout.huawei.com ([185.176.76.210]:32706 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726792AbeJaApG (ORCPT ); Tue, 30 Oct 2018 20:45:06 -0400 Received: from lhreml703-cah.china.huawei.com (unknown [172.18.7.106]) by Forcepoint Email with ESMTP id 5DC4D575F0DA7; Tue, 30 Oct 2018 15:51:03 +0000 (GMT) Received: from roberto-HP-EliteDesk-800-G2-DM-65W.huawei.com (10.204.65.153) by smtpsuk.huawei.com (10.201.108.44) with Microsoft SMTP Server (TLS) id 14.3.408.0; Tue, 30 Oct 2018 15:50:55 +0000 From: Roberto Sassu To: , CC: , , , , Roberto Sassu Subject: [PATCH v3 3/5] tpm: modify tpm_pcr_read() definition to pass a TPM hash algorithm Date: Tue, 30 Oct 2018 16:47:09 +0100 Message-ID: <20181030154711.2782-4-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181030154711.2782-1-roberto.sassu@huawei.com> References: <20181030154711.2782-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.65.153] X-CFilter-Loop: Reflected Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: X-Virus-Scanned: ClamAV using ClamSMTP Currently the TPM driver allows other kernel subsystems to read only the SHA1 PCR bank. This patch modifies the parameters of tpm_pcr_read() and tpm2_pcr_read() to pass a tpm_digest structure, which contains the desired hash algorithm. Also, since commit 125a22105410 ("tpm: React correctly to RC_TESTING from TPM 2.0 self tests") removed the call to tpm2_pcr_read(), the new parameter is expected to be always not NULL. Due to the API change, IMA functions have been modified. Signed-off-by: Roberto Sassu Acked-by: Mimi Zohar --- drivers/char/tpm/tpm-interface.c | 9 +++++---- drivers/char/tpm/tpm.h | 3 ++- drivers/char/tpm/tpm2-cmd.c | 23 ++++++++++++++++------- include/linux/tpm.h | 6 ++++-- security/integrity/ima/ima_crypto.c | 10 +++++----- 5 files changed, 32 insertions(+), 19 deletions(-) diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index 48c8d3ef5944..4d0f5da5bf98 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -976,11 +976,12 @@ EXPORT_SYMBOL_GPL(tpm_is_tpm2); * tpm_pcr_read - read a PCR value from SHA1 bank * @chip: a &struct tpm_chip instance, %NULL for the default chip * @pcr_idx: the PCR to be retrieved - * @res_buf: the value of the PCR + * @digest_struct: pcr bank and buffer current PCR value is written to * * Return: same as with tpm_transmit_cmd() */ -int tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf) +int tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, + struct tpm_digest *digest_struct) { int rc; @@ -988,9 +989,9 @@ int tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf) if (!chip) return -ENODEV; if (chip->flags & TPM_CHIP_FLAG_TPM2) - rc = tpm2_pcr_read(chip, pcr_idx, res_buf); + rc = tpm2_pcr_read(chip, pcr_idx, digest_struct); else - rc = tpm_pcr_read_dev(chip, pcr_idx, res_buf); + rc = tpm_pcr_read_dev(chip, pcr_idx, digest_struct->digest); tpm_put_ops(chip); return rc; } diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index b928ba44d864..633e16f42107 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -564,7 +564,8 @@ static inline u32 tpm2_rc_value(u32 rc) return (rc & BIT(7)) ? rc & 0xff : rc; } -int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf); +int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, + struct tpm_digest *digest_struct); int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, u32 count, struct tpm_digest *digests); int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max); diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c index 4744ab3a6df2..8babd826ad27 100644 --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -179,16 +179,18 @@ struct tpm2_pcr_read_out { * tpm2_pcr_read() - read a PCR value * @chip: TPM chip to use. * @pcr_idx: index of the PCR to read. - * @res_buf: buffer to store the resulting hash. + * @digest_struct: pcr bank and buffer current PCR value is written to. * * Return: Same as with tpm_transmit_cmd. */ -int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf) +int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, + struct tpm_digest *digest_struct) { int rc; struct tpm_buf buf; struct tpm2_pcr_read_out *out; u8 pcr_select[TPM2_PCR_SELECT_MIN] = {0}; + u16 digest_size; if (pcr_idx >= TPM2_PLATFORM_PCR) return -EINVAL; @@ -200,18 +202,25 @@ int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf) pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7); tpm_buf_append_u32(&buf, 1); - tpm_buf_append_u16(&buf, TPM_ALG_SHA1); + tpm_buf_append_u16(&buf, digest_struct->alg_id); tpm_buf_append_u8(&buf, TPM2_PCR_SELECT_MIN); tpm_buf_append(&buf, (const unsigned char *)pcr_select, sizeof(pcr_select)); rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0, - res_buf ? "attempting to read a pcr value" : NULL); - if (rc == 0 && res_buf) { - out = (struct tpm2_pcr_read_out *)&buf.data[TPM_HEADER_SIZE]; - memcpy(res_buf, out->digest, SHA1_DIGEST_SIZE); + "attempting to read a pcr value"); + if (rc) + goto out; + + out = (struct tpm2_pcr_read_out *)&buf.data[TPM_HEADER_SIZE]; + digest_size = be16_to_cpu(out->digest_size); + if (digest_size > sizeof(digest_struct->digest)) { + rc = -EINVAL; + goto out; } + memcpy(digest_struct->digest, out->digest, digest_size); +out: tpm_buf_destroy(&buf); return rc; } diff --git a/include/linux/tpm.h b/include/linux/tpm.h index 71d7bbf5f690..4f00daf44dd2 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -71,7 +71,8 @@ struct tpm_class_ops { #if defined(CONFIG_TCG_TPM) || defined(CONFIG_TCG_TPM_MODULE) extern int tpm_is_tpm2(struct tpm_chip *chip); -extern int tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf); +extern int tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, + struct tpm_digest *digest_struct); extern int tpm_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash); extern int tpm_send(struct tpm_chip *chip, void *cmd, size_t buflen); extern int tpm_get_random(struct tpm_chip *chip, u8 *data, size_t max); @@ -87,7 +88,8 @@ static inline int tpm_is_tpm2(struct tpm_chip *chip) { return -ENODEV; } -static inline int tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf) +static inline int tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, + struct tpm_digest *digest_struct) { return -ENODEV; } diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c index 7e7e7e7c250a..8985e34eb3ac 100644 --- a/security/integrity/ima/ima_crypto.c +++ b/security/integrity/ima/ima_crypto.c @@ -629,12 +629,12 @@ int ima_calc_buffer_hash(const void *buf, loff_t len, return calc_buffer_shash(buf, len, hash); } -static void __init ima_pcrread(int idx, u8 *pcr) +static void __init ima_pcrread(int idx, struct tpm_digest *d) { if (!ima_tpm_chip) return; - if (tpm_pcr_read(ima_tpm_chip, idx, pcr) != 0) + if (tpm_pcr_read(ima_tpm_chip, idx, d) != 0) pr_err("Error Communicating to TPM chip\n"); } @@ -644,7 +644,7 @@ static void __init ima_pcrread(int idx, u8 *pcr) static int __init ima_calc_boot_aggregate_tfm(char *digest, struct crypto_shash *tfm) { - u8 pcr_i[TPM_DIGEST_SIZE]; + struct tpm_digest d = { .alg_id = TPM_ALG_SHA1, .digest = {0} }; int rc, i; SHASH_DESC_ON_STACK(shash, tfm); @@ -657,9 +657,9 @@ static int __init ima_calc_boot_aggregate_tfm(char *digest, /* cumulative sha1 over tpm registers 0-7 */ for (i = TPM_PCR0; i < TPM_PCR8; i++) { - ima_pcrread(i, pcr_i); + ima_pcrread(i, &d); /* now accumulate with current aggregate */ - rc = crypto_shash_update(shash, pcr_i, TPM_DIGEST_SIZE); + rc = crypto_shash_update(shash, d.digest, TPM_DIGEST_SIZE); } if (!rc) crypto_shash_final(shash, digest);