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

Jarkko Sakkinen
2018-11-06T06:10:34Z

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@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@linux.ibm.com>

Great, awesome, thank you for all your reviews!

/Jarkko