LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To: linux-integrity@vger.kernel.org
Cc: linux-security-module@vger.kernel.org,
	Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>,
	Peter Huewe <peterhuewe@gmx.de>, Jason Gunthorpe <jgg@ziepe.ca>,
	Arnd Bergmann <arnd@arndb.de>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	linux-kernel@vger.kernel.org (open list)
Subject: [PATCH v4 2/4] tpm: migrate tpm2_probe() to use struct tpm_buf
Date: Mon, 26 Mar 2018 15:14:04 +0300	[thread overview]
Message-ID: <20180326121406.14548-3-jarkko.sakkinen@linux.intel.com> (raw)
In-Reply-To: <20180326121406.14548-1-jarkko.sakkinen@linux.intel.com>

In order to make struct tpm_buf the first class object for constructing TPM
commands, migrate tpm2_probe() to use it.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Acked-by: Jay Freyensee <why2jjj.linux@gmail.com>
---
 drivers/char/tpm/tpm2-cmd.c | 37 +++++++++++++++++++++----------------
 1 file changed, 21 insertions(+), 16 deletions(-)

diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 7665661d9230..7bffd0fd1dca 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -844,30 +844,35 @@ static int tpm2_do_selftest(struct tpm_chip *chip)
 
 /**
  * tpm2_probe() - probe TPM 2.0
- * @chip: TPM chip to use
+ * @chip: a TPM chip to probe
  *
- * Return: < 0 error and 0 on success.
+ * Return: 0 on success,
+ *         -errno otherwise
  *
- * Send idempotent TPM 2.0 command and see whether TPM 2.0 chip replied based on
- * the reply tag.
+ * Send an idempotent TPM 2.0 command and see whether there is TPM2 chip in the
+ * other end based on the response tag. The flag TPM_CHIP_FLAG_TPM2 is set if
+ * this is the case.
  */
 int tpm2_probe(struct tpm_chip *chip)
 {
-	struct tpm2_cmd cmd;
+	struct tpm_output_header *out;
+	struct tpm_buf buf;
 	int rc;
 
-	cmd.header.in = tpm2_get_tpm_pt_header;
-	cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
-	cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(0x100);
-	cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
-
-	rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, 0, NULL);
-	if (rc <  0)
+	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
+	if (rc)
 		return rc;
-
-	if (be16_to_cpu(cmd.header.out.tag) == TPM2_ST_NO_SESSIONS)
-		chip->flags |= TPM_CHIP_FLAG_TPM2;
-
+	tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
+	tpm_buf_append_u32(&buf, TPM_PT_TOTAL_COMMANDS);
+	tpm_buf_append_u32(&buf, 1);
+	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0, NULL);
+	/* We ignore TPM return codes on purpose. */
+	if (rc >=  0) {
+		out = (struct tpm_output_header *)buf.data;
+		if (be16_to_cpu(out->tag) == TPM2_ST_NO_SESSIONS)
+			chip->flags |= TPM_CHIP_FLAG_TPM2;
+	}
+	tpm_buf_destroy(&buf);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(tpm2_probe);
-- 
2.15.1

  parent reply	other threads:[~2018-03-26 12:14 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-03-26 12:14 [PATCH v4 0/4] Migrate all TPM 2.0 commands " Jarkko Sakkinen
2018-03-26 12:14 ` [PATCH v4 1/4] tpm: migrate tpm2_shutdown() " Jarkko Sakkinen
2018-05-18  6:29   ` Nayna Jain
2018-05-18 22:30   ` Jerry Snitselaar
2018-05-23 12:56     ` Jarkko Sakkinen
2018-05-27  9:14       ` Jerry Snitselaar
2018-06-05 19:35         ` Jarkko Sakkinen
2018-03-26 12:14 ` Jarkko Sakkinen [this message]
2018-05-18  6:31   ` [PATCH v4 2/4] tpm: migrate tpm2_probe() " Nayna Jain
2018-05-18 22:35   ` Jerry Snitselaar
2018-03-26 12:14 ` [PATCH v4 3/4] tpm: migrate tpm2_get_tpm_pt() " Jarkko Sakkinen
2018-05-18  6:31   ` Nayna Jain
2018-05-18  8:05     ` Jarkko Sakkinen
2018-05-18 22:39   ` Jerry Snitselaar
2018-03-26 12:14 ` [PATCH v4 4/4] tpm: migrate tpm2_get_random() " Jarkko Sakkinen
2018-05-18  6:09   ` Nayna Jain
2018-05-18  8:03     ` Jarkko Sakkinen
2018-04-06 10:31 ` [PATCH v4 0/4] Migrate all TPM 2.0 commands " Jarkko Sakkinen

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20180326121406.14548-3-jarkko.sakkinen@linux.intel.com \
    --to=jarkko.sakkinen@linux.intel.com \
    --cc=arnd@arndb.de \
    --cc=gregkh@linuxfoundation.org \
    --cc=jgg@ziepe.ca \
    --cc=linux-integrity@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-security-module@vger.kernel.org \
    --cc=peterhuewe@gmx.de \
    --subject='Re: [PATCH v4 2/4] tpm: migrate tpm2_probe() to use struct tpm_buf' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).