[PATCH v3 08/16] tpm: move tpm_validate_commmand() to tpm2-space.c

Jarkko Sakkinen jarkko.sakkinen at linux.intel.com
Tue Nov 6 06:10:20 UTC 2018


On Mon, Nov 05, 2018 at 05:36:03PM -0500, Stefan Berger wrote:
> On 11/4/18 8:45 PM, Jarkko Sakkinen wrote:
> > Move tpm_validate_command() to tpm2-space.c and make it part of the
> > tpm2_prepare_space() flow. Make cc resolution as part of the TPM space
> > functionality in order to detach it from rest of the tpm_transmit()
> > flow.
> > 
> > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen at linux.intel.com>
> > ---
> >   drivers/char/tpm/tpm-interface.c | 72 +++++++-------------------------
> >   drivers/char/tpm/tpm.h           |  9 ++--
> >   drivers/char/tpm/tpm2-space.c    | 54 +++++++++++++++++++++---
> >   3 files changed, 68 insertions(+), 67 deletions(-)
> > 
> > diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
> > index 422e3bb0bd3d..3bf0c51b7b4f 100644
> > --- a/drivers/char/tpm/tpm-interface.c
> > +++ b/drivers/char/tpm/tpm-interface.c
> > @@ -62,47 +62,6 @@ unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
> >   }
> >   EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
> > 
> > -static int tpm_validate_command(struct tpm_chip *chip,
> > -				 struct tpm_space *space,
> > -				 const u8 *cmd,
> > -				 size_t len)
> > -{
> > -	const struct tpm_input_header *header = (const void *)cmd;
> > -	int i;
> > -	u32 cc;
> > -	u32 attrs;
> > -	unsigned int nr_handles;
> > -
> > -	if (len < TPM_HEADER_SIZE)
> > -		return -EINVAL;
> > -
> > -	if (!space)
> > -		return 0;
> > -
> > -	if (chip->flags & TPM_CHIP_FLAG_TPM2 && chip->nr_commands) {
> > -		cc = be32_to_cpu(header->ordinal);
> > -
> > -		i = tpm2_find_cc(chip, cc);
> > -		if (i < 0) {
> > -			dev_dbg(&chip->dev, "0x%04X is an invalid command\n",
> > -				cc);
> > -			return -EOPNOTSUPP;
> > -		}
> > -
> > -		attrs = chip->cc_attrs_tbl[i];
> > -		nr_handles =
> > -			4 * ((attrs >> TPM2_CC_ATTR_CHANDLES) & GENMASK(2, 0));
> > -		if (len < TPM_HEADER_SIZE + 4 * nr_handles)
> > -			goto err_len;
> > -	}
> > -
> > -	return 0;
> > -err_len:
> > -	dev_dbg(&chip->dev,
> > -		"%s: insufficient command length %zu", __func__, len);
> > -	return -EINVAL;
> > -}
> > -
> >   static int tpm_request_locality(struct tpm_chip *chip, unsigned int flags)
> >   {
> >   	int rc;
> > @@ -172,20 +131,8 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip,
> >   	u32 count, ordinal;
> >   	unsigned long stop;
> > 
> > -	rc = tpm_validate_command(chip, space, buf, bufsiz);
> > -	if (rc == -EINVAL)
> > -		return rc;
> > -	/*
> > -	 * If the command is not implemented by the TPM, synthesize a
> > -	 * response with a TPM2_RC_COMMAND_CODE return for user-space.
> > -	 */
> > -	if (rc == -EOPNOTSUPP) {
> > -		header->length = cpu_to_be32(sizeof(*header));
> > -		header->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
> > -		header->return_code = cpu_to_be32(TPM2_RC_COMMAND_CODE |
> > -						  TSS2_RESMGR_TPM_RC_LAYER);
> > -		return sizeof(*header);
> > -	}
> > +	if (bufsiz < TPM_HEADER_SIZE)
> > +		return -EINVAL;
> > 
> >   	if (bufsiz > TPM_BUFSIZE)
> >   		bufsiz = TPM_BUFSIZE;
> > @@ -200,7 +147,18 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip,
> >   		return -E2BIG;
> >   	}
> > 
> > -	rc = tpm2_prepare_space(chip, space, ordinal, buf);
> > +	rc = tpm2_prepare_space(chip, space, buf, bufsiz);
> > +	/*
> > +	 * If the command is not implemented by the TPM, synthesize a
> > +	 * response with a TPM2_RC_COMMAND_CODE return for user-space.
> > +	 */
> > +	if (rc == -EOPNOTSUPP) {
> > +		header->length = cpu_to_be32(sizeof(*header));
> > +		header->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
> > +		header->return_code = cpu_to_be32(TPM2_RC_COMMAND_CODE |
> > +						  TSS2_RESMGR_TPM_RC_LAYER);
> > +		return sizeof(*header);
> > +	}
> >   	if (rc)
> >   		return rc;
> > 
> > @@ -251,7 +209,7 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip,
> >   	if (rc)
> >   		tpm2_flush_space(chip);
> >   	else
> > -		rc = tpm2_commit_space(chip, space, ordinal, buf, &len);
> > +		rc = tpm2_commit_space(chip, space, buf, &len);
> > 
> >   	return rc ? rc : len;
> >   }
> > diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
> > index 229ac42b644e..8503dd261897 100644
> > --- a/drivers/char/tpm/tpm.h
> > +++ b/drivers/char/tpm/tpm.h
> > @@ -264,6 +264,7 @@ struct tpm_chip {
> >   #endif /* CONFIG_ACPI */
> > 
> >   	struct tpm_space work_space;
> > +	u32 last_cc;
> >   	u32 nr_commands;
> >   	u32 *cc_attrs_tbl;
> > 
> > @@ -580,10 +581,10 @@ int tpm2_find_cc(struct tpm_chip *chip, u32 cc);
> >   int tpm2_init_space(struct tpm_space *space);
> >   void tpm2_del_space(struct tpm_chip *chip, struct tpm_space *space);
> >   void tpm2_flush_space(struct tpm_chip *chip);
> > -int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u32 cc,
> > -		       u8 *cmd);
> > -int tpm2_commit_space(struct tpm_chip *chip, struct tpm_space *space,
> > -		      u32 cc, u8 *buf, size_t *bufsiz);
> > +int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u8 *cmd,
> > +		       size_t cmdsiz);
> > +int tpm2_commit_space(struct tpm_chip *chip, struct tpm_space *space, u8 *buf,
> > +		       size_t *bufsiz);
> > 
> >   int tpm_bios_log_setup(struct tpm_chip *chip);
> >   void tpm_bios_log_teardown(struct tpm_chip *chip);
> > diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c
> > index 3d5f9577e5de..20c295fadd50 100644
> > --- a/drivers/char/tpm/tpm2-space.c
> > +++ b/drivers/char/tpm/tpm2-space.c
> > @@ -264,14 +264,55 @@ static int tpm2_map_command(struct tpm_chip *chip, u32 cc, u8 *cmd)
> >   	return 0;
> >   }
> > 
> > -int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u32 cc,
> > -		       u8 *cmd)
> > +static int tpm_validate_command(struct tpm_chip *chip, struct tpm_space *space,
> > +				const u8 *cmd, size_t len)
> 
> 
> Nit: len -> cmdsiz (like below)
> 
> 
> > +{
> > +	const struct tpm_input_header *header = (const void *)cmd;
> > +	int i;
> > +	u32 cc;
> > +	u32 attrs;
> > +	unsigned int nr_handles;
> > +
> > +	if (len < TPM_HEADER_SIZE)
> > +		return -EINVAL;
> > +
> > +	if (chip->nr_commands) {
> > +		cc = be32_to_cpu(header->ordinal);
> > +
> > +		i = tpm2_find_cc(chip, cc);
> > +		if (i < 0) {
> > +			dev_dbg(&chip->dev, "0x%04X is an invalid command\n",
> > +				cc);
> > +			return -EOPNOTSUPP;
> > +		}
> > +
> > +		attrs = chip->cc_attrs_tbl[i];
> > +		nr_handles =
> > +			4 * ((attrs >> TPM2_CC_ATTR_CHANDLES) & GENMASK(2, 0));
> > +		if (len < TPM_HEADER_SIZE + 4 * nr_handles)
> > +			goto err_len;
> > +	}
> > +
> > +	return cc;
> > +err_len:
> > +	dev_dbg(&chip->dev, "%s: insufficient command length %zu", __func__,
> > +		len);
> > +	return -EINVAL;
> > +}
> > +
> > +int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u8 *cmd,
> > +		       size_t cmdsiz)
> >   {
> >   	int rc;
> > +	int cc;
> > 
> >   	if (!space)
> >   		return 0;
> > 
> > +	cc = tpm_validate_command(chip, space, cmd, cmdsiz);
> > +	if (cc < 0)
> > +		return cc;
> > +
> >   	memcpy(&chip->work_space.context_tbl, &space->context_tbl,
> >   	       sizeof(space->context_tbl));
> >   	memcpy(&chip->work_space.session_tbl, &space->session_tbl,
> > @@ -291,6 +332,7 @@ int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u32 cc,
> >   		return rc;
> >   	}
> > 
> > +	chip->last_cc = cc;
> >   	return 0;
> >   }
> > 
> > @@ -489,8 +531,8 @@ static int tpm2_save_space(struct tpm_chip *chip)
> >   	return 0;
> >   }
> > 
> > -int tpm2_commit_space(struct tpm_chip *chip, struct tpm_space *space,
> > -		      u32 cc, u8 *buf, size_t *bufsiz)
> > +int tpm2_commit_space(struct tpm_chip *chip, struct tpm_space *space, u8 *buf,
> > +		      size_t *bufsiz)
> >   {
> >   	struct tpm_output_header *header = (void *)buf;
> >   	int rc;
> > @@ -498,13 +540,13 @@ int tpm2_commit_space(struct tpm_chip *chip, struct tpm_space *space,
> >   	if (!space)
> >   		return 0;
> > 
> > -	rc = tpm2_map_response_header(chip, cc, buf, *bufsiz);
> > +	rc = tpm2_map_response_header(chip, chip->last_cc, buf, *bufsiz);
> >   	if (rc) {
> >   		tpm2_flush_space(chip);
> >   		goto out;
> >   	}
> > 
> > -	rc = tpm2_map_response_body(chip, cc, buf, *bufsiz);
> > +	rc = tpm2_map_response_body(chip, chip->last_cc, buf, *bufsiz);
> >   	if (rc) {
> >   		tpm2_flush_space(chip);
> >   		goto out;
> 
> Rest looks good.
> 
> Reviewed-by: Stefan Berger <stefanb at linux.ibm.com>

Great, awesome, thank you for all your reviews!

/Jarkko



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