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* [PATCH] tpm: Add Upgrade/Reduced mode support for TPM2 modules
@ 2021-07-19 13:37 Borys Movchan
  2021-07-27  2:58 ` Jarkko Sakkinen
  0 siblings, 1 reply; 3+ messages in thread
From: Borys Movchan @ 2021-07-19 13:37 UTC (permalink / raw)
  To: Peter Huewe, Jarkko Sakkinen, Jason Gunthorpe
  Cc: kernel, Borys Movchan, linux-integrity, linux-kernel

On some systems, especially embedded, TPM might start in
Upgrade/Reduced mode due to the previous failure of a firmware
upgrade process. Allow the TPM driver to handle such situations
properly. Enables a possibility for userspace application to
finalize TPM upgrade or recovery if required.

Signed-off-by: Borys Movchan <borysmn@axis.com>
---
 drivers/char/tpm/tpm-chip.c | 23 +++++++++++++++--------
 drivers/char/tpm/tpm2-cmd.c | 12 ++++++++++--
 include/linux/tpm.h         |  1 +
 3 files changed, 26 insertions(+), 10 deletions(-)

diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index ddaeceb7e109..ff2367c447fb 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -574,20 +574,25 @@ static int tpm_get_pcr_allocation(struct tpm_chip *chip)
 int tpm_chip_register(struct tpm_chip *chip)
 {
 	int rc;
+	bool limited_mode = false;
 
 	rc = tpm_chip_start(chip);
 	if (rc)
 		return rc;
 	rc = tpm_auto_startup(chip);
-	if (rc) {
+	if (rc == -EIO) {
+		limited_mode = true;
+	} else if (rc) {
 		tpm_chip_stop(chip);
 		return rc;
 	}
 
-	rc = tpm_get_pcr_allocation(chip);
-	tpm_chip_stop(chip);
-	if (rc)
-		return rc;
+	if (!limited_mode) {
+		rc = tpm_get_pcr_allocation(chip);
+		tpm_chip_stop(chip);
+		if (rc)
+			return rc;
+	}
 
 	tpm_sysfs_add_device(chip);
 
@@ -595,9 +600,11 @@ int tpm_chip_register(struct tpm_chip *chip)
 
 	tpm_add_ppi(chip);
 
-	rc = tpm_add_hwrng(chip);
-	if (rc)
-		goto out_ppi;
+	if (!limited_mode) {
+		rc = tpm_add_hwrng(chip);
+		if (rc)
+			goto out_ppi;
+	}
 
 	rc = tpm_add_char_device(chip);
 	if (rc)
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index a25815a6f625..7468353ed67d 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -718,7 +718,8 @@ static int tpm2_startup(struct tpm_chip *chip)
  *                     sequence
  * @chip: TPM chip to use
  *
- * Returns 0 on success, < 0 in case of fatal error.
+ * Returns 0 on success, -ENODEV in case of fatal error,
+ *	    -EIO in case of Reduced/Upgrade mode
  */
 int tpm2_auto_startup(struct tpm_chip *chip)
 {
@@ -729,7 +730,10 @@ int tpm2_auto_startup(struct tpm_chip *chip)
 		goto out;
 
 	rc = tpm2_do_selftest(chip);
-	if (rc && rc != TPM2_RC_INITIALIZE)
+	if (rc == TPM2_RC_UPGRADE) {
+		rc = -EIO;
+		goto out;
+	} else if (rc && rc != TPM2_RC_INITIALIZE)
 		goto out;
 
 	if (rc == TPM2_RC_INITIALIZE) {
@@ -743,6 +747,10 @@ int tpm2_auto_startup(struct tpm_chip *chip)
 	}
 
 	rc = tpm2_get_cc_attrs_tbl(chip);
+	if (rc) { /* Succeeded until here, but failed -> reduced mode */
+		rc = -EIO;
+		goto out;
+	}
 
 out:
 	if (rc > 0)
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index aa11fe323c56..e873c42907f0 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -207,6 +207,7 @@ enum tpm2_return_codes {
 	TPM2_RC_INITIALIZE	= 0x0100, /* RC_VER1 */
 	TPM2_RC_FAILURE		= 0x0101,
 	TPM2_RC_DISABLED	= 0x0120,
+	TPM2_RC_UPGRADE		= 0x012D,
 	TPM2_RC_COMMAND_CODE    = 0x0143,
 	TPM2_RC_TESTING		= 0x090A, /* RC_WARN */
 	TPM2_RC_REFERENCE_H0	= 0x0910,
-- 
2.20.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread
* Re: [PATCH] tpm: Add Upgrade/Reduced mode support for TPM2 modules
  2021-07-19 13:37 [PATCH] tpm: Add Upgrade/Reduced mode support for TPM2 modules Borys Movchan
@ 2021-07-27  2:58 ` Jarkko Sakkinen
  2021-07-28 11:06   ` Borys Movchan
  0 siblings, 1 reply; 3+ messages in thread
From: Jarkko Sakkinen @ 2021-07-27  2:58 UTC (permalink / raw)
  To: Borys Movchan
  Cc: Peter Huewe, Jason Gunthorpe, kernel, linux-integrity, linux-kernel

On Mon, Jul 19, 2021 at 03:37:17PM +0200, Borys Movchan wrote:
> On some systems, especially embedded, TPM might start in
> Upgrade/Reduced mode due to the previous failure of a firmware
> upgrade process. Allow the TPM driver to handle such situations
> properly. Enables a possibility for userspace application to
> finalize TPM upgrade or recovery if required.


Please add short explanation what you mean by upgrade/reduced mode.

Maybe for clarity speak about upgrade mode.

> 
> Signed-off-by: Borys Movchan <borysmn@axis.com>
> ---
>  drivers/char/tpm/tpm-chip.c | 23 +++++++++++++++--------
>  drivers/char/tpm/tpm2-cmd.c | 12 ++++++++++--
>  include/linux/tpm.h         |  1 +
>  3 files changed, 26 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
> index ddaeceb7e109..ff2367c447fb 100644
> --- a/drivers/char/tpm/tpm-chip.c
> +++ b/drivers/char/tpm/tpm-chip.c
> @@ -574,20 +574,25 @@ static int tpm_get_pcr_allocation(struct tpm_chip *chip)
>  int tpm_chip_register(struct tpm_chip *chip)
>  {
>  	int rc;
> +	bool limited_mode = false;
>  
>  	rc = tpm_chip_start(chip);
>  	if (rc)
>  		return rc;
>  	rc = tpm_auto_startup(chip);
> -	if (rc) {
> +	if (rc == -EIO) {
> +		limited_mode = true;
> +	} else if (rc) {
>  		tpm_chip_stop(chip);
>  		return rc;
>  	}
>  
> -	rc = tpm_get_pcr_allocation(chip);
> -	tpm_chip_stop(chip);
> -	if (rc)
> -		return rc;
> +	if (!limited_mode) {
> +		rc = tpm_get_pcr_allocation(chip);
> +		tpm_chip_stop(chip);
> +		if (rc)
> +			return rc;
> +	}
>  
>  	tpm_sysfs_add_device(chip);
>  
> @@ -595,9 +600,11 @@ int tpm_chip_register(struct tpm_chip *chip)
>  
>  	tpm_add_ppi(chip);
>  
> -	rc = tpm_add_hwrng(chip);
> -	if (rc)
> -		goto out_ppi;
> +	if (!limited_mode) {
> +		rc = tpm_add_hwrng(chip);
> +		if (rc)
> +			goto out_ppi;
> +	}
>  
>  	rc = tpm_add_char_device(chip);
>  	if (rc)
> diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
> index a25815a6f625..7468353ed67d 100644
> --- a/drivers/char/tpm/tpm2-cmd.c
> +++ b/drivers/char/tpm/tpm2-cmd.c
> @@ -718,7 +718,8 @@ static int tpm2_startup(struct tpm_chip *chip)
>   *                     sequence
>   * @chip: TPM chip to use
>   *
> - * Returns 0 on success, < 0 in case of fatal error.
> + * Returns 0 on success, -ENODEV in case of fatal error,
> + *	    -EIO in case of Reduced/Upgrade mode
>   */
>  int tpm2_auto_startup(struct tpm_chip *chip)
>  {
> @@ -729,7 +730,10 @@ int tpm2_auto_startup(struct tpm_chip *chip)
>  		goto out;
>  
>  	rc = tpm2_do_selftest(chip);
> -	if (rc && rc != TPM2_RC_INITIALIZE)
> +	if (rc == TPM2_RC_UPGRADE) {
> +		rc = -EIO;
> +		goto out;
> +	} else if (rc && rc != TPM2_RC_INITIALIZE)
>  		goto out;
>  
>  	if (rc == TPM2_RC_INITIALIZE) {
> @@ -743,6 +747,10 @@ int tpm2_auto_startup(struct tpm_chip *chip)
>  	}
>  
>  	rc = tpm2_get_cc_attrs_tbl(chip);
> +	if (rc) { /* Succeeded until here, but failed -> reduced mode */
> +		rc = -EIO;
> +		goto out;
> +	}
>  
>  out:
>  	if (rc > 0)
> diff --git a/include/linux/tpm.h b/include/linux/tpm.h
> index aa11fe323c56..e873c42907f0 100644
> --- a/include/linux/tpm.h
> +++ b/include/linux/tpm.h
> @@ -207,6 +207,7 @@ enum tpm2_return_codes {
>  	TPM2_RC_INITIALIZE	= 0x0100, /* RC_VER1 */
>  	TPM2_RC_FAILURE		= 0x0101,
>  	TPM2_RC_DISABLED	= 0x0120,
> +	TPM2_RC_UPGRADE		= 0x012D,
>  	TPM2_RC_COMMAND_CODE    = 0x0143,
>  	TPM2_RC_TESTING		= 0x090A, /* RC_WARN */
>  	TPM2_RC_REFERENCE_H0	= 0x0910,
> -- 
> 2.20.1
> 
> 

/Jarkko

^ permalink raw reply	[flat|nested] 3+ messages in thread
* Re: [PATCH] tpm: Add Upgrade/Reduced mode support for TPM2 modules
  2021-07-27  2:58 ` Jarkko Sakkinen
@ 2021-07-28 11:06   ` Borys Movchan
  0 siblings, 0 replies; 3+ messages in thread
From: Borys Movchan @ 2021-07-28 11:06 UTC (permalink / raw)
  To: Jarkko Sakkinen
  Cc: Peter Huewe, Jason Gunthorpe, kernel, linux-integrity, linux-kernel

On 7/27/21 4:58 AM, Jarkko Sakkinen wrote:
> On Mon, Jul 19, 2021 at 03:37:17PM +0200, Borys Movchan wrote:
> > On some systems, especially embedded, TPM might start in
> > Upgrade/Reduced mode due to the previous failure of a firmware
> > upgrade process. Allow the TPM driver to handle such situations
> > properly. Enables a possibility for userspace application to
> > finalize TPM upgrade or recovery if required.
>
>
> Please add short explanation what you mean by upgrade/reduced mode.
>
> Maybe for clarity speak about upgrade mode.

I have send v2 patch with updated commit message and some notes.

Hope that would be more clear.

>
> >
> > Signed-off-by: Borys Movchan <borysmn@axis.com>
> > ---
> >  drivers/char/tpm/tpm-chip.c | 23 +++++++++++++++--------
> >  drivers/char/tpm/tpm2-cmd.c | 12 ++++++++++--
> >  include/linux/tpm.h         |  1 +
> >  3 files changed, 26 insertions(+), 10 deletions(-)
> >
> > diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
> > index ddaeceb7e109..ff2367c447fb 100644
> > --- a/drivers/char/tpm/tpm-chip.c
> > +++ b/drivers/char/tpm/tpm-chip.c
> > @@ -574,20 +574,25 @@ static int tpm_get_pcr_allocation(struct 
> tpm_chip *chip)
> >  int tpm_chip_register(struct tpm_chip *chip)
> >  {
> >        int rc;
> > +     bool limited_mode = false;
> >
> >        rc = tpm_chip_start(chip);
> >        if (rc)
> >                return rc;
> >        rc = tpm_auto_startup(chip);
> > -     if (rc) {
> > +     if (rc == -EIO) {
> > +             limited_mode = true;
> > +     } else if (rc) {
> >                tpm_chip_stop(chip);
> >                return rc;
> >        }
> >
> > -     rc = tpm_get_pcr_allocation(chip);
> > -     tpm_chip_stop(chip);
> > -     if (rc)
> > -             return rc;
> > +     if (!limited_mode) {
> > +             rc = tpm_get_pcr_allocation(chip);
> > +             tpm_chip_stop(chip);
> > +             if (rc)
> > +                     return rc;
> > +     }
> >
> >        tpm_sysfs_add_device(chip);
> >
> > @@ -595,9 +600,11 @@ int tpm_chip_register(struct tpm_chip *chip)
> >
> >        tpm_add_ppi(chip);
> >
> > -     rc = tpm_add_hwrng(chip);
> > -     if (rc)
> > -             goto out_ppi;
> > +     if (!limited_mode) {
> > +             rc = tpm_add_hwrng(chip);
> > +             if (rc)
> > +                     goto out_ppi;
> > +     }
> >
> >        rc = tpm_add_char_device(chip);
> >        if (rc)
> > diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
> > index a25815a6f625..7468353ed67d 100644
> > --- a/drivers/char/tpm/tpm2-cmd.c
> > +++ b/drivers/char/tpm/tpm2-cmd.c
> > @@ -718,7 +718,8 @@ static int tpm2_startup(struct tpm_chip *chip)
> >   *                     sequence
> >   * @chip: TPM chip to use
> >   *
> > - * Returns 0 on success, < 0 in case of fatal error.
> > + * Returns 0 on success, -ENODEV in case of fatal error,
> > + *       -EIO in case of Reduced/Upgrade mode
> >   */
> >  int tpm2_auto_startup(struct tpm_chip *chip)
> >  {
> > @@ -729,7 +730,10 @@ int tpm2_auto_startup(struct tpm_chip *chip)
> >                goto out;
> >
> >        rc = tpm2_do_selftest(chip);
> > -     if (rc && rc != TPM2_RC_INITIALIZE)
> > +     if (rc == TPM2_RC_UPGRADE) {
> > +             rc = -EIO;
> > +             goto out;
> > +     } else if (rc && rc != TPM2_RC_INITIALIZE)
> >                goto out;
> >
> >        if (rc == TPM2_RC_INITIALIZE) {
> > @@ -743,6 +747,10 @@ int tpm2_auto_startup(struct tpm_chip *chip)
> >        }
> >
> >        rc = tpm2_get_cc_attrs_tbl(chip);
> > +     if (rc) { /* Succeeded until here, but failed -> reduced mode */
> > +             rc = -EIO;
> > +             goto out;
> > +     }
> >
> >  out:
> >        if (rc > 0)
> > diff --git a/include/linux/tpm.h b/include/linux/tpm.h
> > index aa11fe323c56..e873c42907f0 100644
> > --- a/include/linux/tpm.h
> > +++ b/include/linux/tpm.h
> > @@ -207,6 +207,7 @@ enum tpm2_return_codes {
> >        TPM2_RC_INITIALIZE      = 0x0100, /* RC_VER1 */
> >        TPM2_RC_FAILURE         = 0x0101,
> >        TPM2_RC_DISABLED        = 0x0120,
> > +     TPM2_RC_UPGRADE         = 0x012D,
> >        TPM2_RC_COMMAND_CODE    = 0x0143,
> >        TPM2_RC_TESTING         = 0x090A, /* RC_WARN */
> >        TPM2_RC_REFERENCE_H0    = 0x0910,
> > --
> > 2.20.1
> >
> >
>
> /Jarkko

Kind regards,

Borys


^ permalink raw reply	[flat|nested] 3+ messages in thread
end of thread, other threads:[~2021-07-28 11:04 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-07-19 13:37 [PATCH] tpm: Add Upgrade/Reduced mode support for TPM2 modules Borys Movchan
2021-07-27  2:58 ` Jarkko Sakkinen
2021-07-28 11:06   ` Borys Movchan

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