[SLOF] [PATCH 14/16] Add TPM firmware API call pass-through-to-tpm

[Nikunj A Dadhania]

Stefan Berger <stefanb at linux.vnet.ibm.com> writes:

> This patch adds support for the firmware API call pass-through-to-tpm.
>
> Signed-off-by: Stefan Berger <stefanb at linux.vnet.ibm.com>

Reviewed-by: Nikunj A Dadhania <nikunj at linux.vnet.ibm.com>

> ---
>  board-qemu/slof/vio-vtpm-cdriver.fs |  8 ++++++++
>  board-qemu/slof/vtpm-sml.fs         |  7 +++++++
>  lib/libtpm/tcgbios.c                | 28 ++++++++++++++++++++++++++++
>  lib/libtpm/tcgbios.h                |  1 +
>  lib/libtpm/tpm.code                 | 11 +++++++++++
>  lib/libtpm/tpm.in                   |  1 +
>  slof/fs/tpm/tpm-static.fs           | 13 +++++++++++++
>  7 files changed, 69 insertions(+)
>
> diff --git a/board-qemu/slof/vio-vtpm-cdriver.fs b/board-qemu/slof/vio-vtpm-cdriver.fs
> index 22fef4f..5d55148 100644
> --- a/board-qemu/slof/vio-vtpm-cdriver.fs
> +++ b/board-qemu/slof/vio-vtpm-cdriver.fs
> @@ -96,6 +96,14 @@ false VALUE vtpm-debug?
>  ;
>
>  \ firmware API call
> +: pass-through-to-tpm ( buf-addr buf-size -- response-size )
> +    " pass-through-to-tpm" call-forward IF
> +        2drop
> +        0
> +    THEN
> +;
> +
> +\ firmware API call
>  : get-maximum-cmd-size ( -- maximum-size )
>      " get-maximum-cmd-size" call-forward IF
>          0
> diff --git a/board-qemu/slof/vtpm-sml.fs b/board-qemu/slof/vtpm-sml.fs
> index e62c20c..3ce1ace 100644
> --- a/board-qemu/slof/vtpm-sml.fs
> +++ b/board-qemu/slof/vtpm-sml.fs
> @@ -80,6 +80,13 @@ log-base LOG-SIZE tpm-set-log-parameters
>      vtpm-get-maximum-cmd-size
>  ;
>
> +: pass-through-to-tpm ( buf-addr cmd-size -- rsp-size )
> +    vtpm-debug? IF
> +        ." Call to pass-through-to-tpm" cr
> +    THEN
> +    vtpm-pass-through-to-tpm
> +;
> +
>  : open  true ;
>  : close ;
>
> diff --git a/lib/libtpm/tcgbios.c b/lib/libtpm/tcgbios.c
> index b306edf..6c991b2 100644
> --- a/lib/libtpm/tcgbios.c
> +++ b/lib/libtpm/tcgbios.c
> @@ -640,6 +640,34 @@ static bool pass_through_to_tpm(unsigned char *req,
>  }
>
>  /*
> + * tpm_pass_through_to_tpm: Function for interfacing with the firmware API
> + *
> + * buf: buffer holding the command; also used for holding the entire response
> + * cmdlen: length of the command in the buffer
> + *
> + * Returns 0 in case of failure, the size of the response otherwise.
> + */
> +uint32_t tpm_pass_through_to_tpm(unsigned char *buf, uint32_t cmdlen)
> +{
> +	uint32_t resplen = PAPR_VTPM_MAX_BUFFER_SIZE;
> +
> +	/*
> +	 * API spec: caller must ensure that the buffer is large
> +	 *           enough to receive the full response into
> +	 *           the same buffer where the command is in.
> +	 *           We anticipate the largest possible buffer
> +	 *           the driver supports in 'resplen'.
> +	 * For duration we use the worst-case timeout 'LONG'
> +	 * so that any command can be sent and will not time out.
> +	 */
> +	if (pass_through_to_tpm(buf, cmdlen,
> +				TPM_DURATION_TYPE_LONG,
> +				buf, &resplen))
> +		return 0;
> +	return resplen;
> +}
> +
> +/*
>   * Extend a PCR of the TPM with the given hash
>   *
>   * @hash: sha1 hash (20 bytes) to extend PCR with
> diff --git a/lib/libtpm/tcgbios.h b/lib/libtpm/tcgbios.h
> index 2aa7d20..6951af3 100644
> --- a/lib/libtpm/tcgbios.h
> +++ b/lib/libtpm/tcgbios.h
> @@ -37,6 +37,7 @@ uint32_t tpm_hash_log_extend_event(struct pcpes *pcpes);
>  bool tpm_log_event(struct pcpes *pcpes);
>  uint32_t tpm_hash_all(const void *data, uint32_t datalen, void *hashptr);
>  uint32_t tpm_get_maximum_cmd_size(void);
> +uint32_t tpm_pass_through_to_tpm(unsigned char *buf, uint32_t cmdlen);
>
>  /* flags returned by tpm_get_state */
>  #define TPM_STATE_ENABLED        1
> diff --git a/lib/libtpm/tpm.code b/lib/libtpm/tpm.code
> index 5c3d4db..e763f45 100644
> --- a/lib/libtpm/tpm.code
> +++ b/lib/libtpm/tpm.code
> @@ -174,3 +174,14 @@ PRIM(tpm_X2d_get_X2d_maximum_X2d_cmd_X2d_size)
>  	PUSH;
>  	TOS.n = tpm_get_maximum_cmd_size();
>  MIRP
> +
> +/*******************************************************************/
> +/* Firmware API                                                    */
> +/* SLOF:   tpm-pass-through-to-tpm (buf-addr cmd-size -- rsp-size) */
> +/* LIBTPM: respsize = tpm_pass_through_to_tpm(buf, cmdsize)        */
> +/*******************************************************************/
> +PRIM(tpm_X2d_pass_X2d_through_X2d_to_X2d_tpm)
> +	int cmdsize = TOS.n; POP;
> +	void *buf = TOS.a;
> +	TOS.n = tpm_pass_through_to_tpm(buf, cmdsize);
> +MIRP
> diff --git a/lib/libtpm/tpm.in b/lib/libtpm/tpm.in
> index 0923fc0..8b7cde8 100644
> --- a/lib/libtpm/tpm.in
> +++ b/lib/libtpm/tpm.in
> @@ -28,3 +28,4 @@ cod(tpm-log-event)
>  cod(tpm-hash-log-extend-event)
>  cod(tpm-hash-all)
>  cod(tpm-get-maximum-cmd-size)
> +cod(tpm-pass-through-to-tpm)
> diff --git a/slof/fs/tpm/tpm-static.fs b/slof/fs/tpm/tpm-static.fs
> index fca0058..f9583b0 100644
> --- a/slof/fs/tpm/tpm-static.fs
> +++ b/slof/fs/tpm/tpm-static.fs
> @@ -120,6 +120,19 @@ false VALUE vtpm-debug?
>      THEN
>  ;
>
> +\ firmware API function
> +: vtpm-pass-through-to-tpm ( buf-addr cmd-size -- rsp-size )
> +    vtpm-available? IF
> +        tpm-pass-through-to-tpm                            ( -- rsp-size )
> +        vtpm-debug? IF
> +            ." VTPM: Return value from tpm-pass-through-to-tpm: " dup . cr
> +        THEN
> +    ELSE
> +        2drop
> +        0
> +    THEN
> +;
> +
>  1 CONSTANT TPM_ST_ENABLED
>  2 CONSTANT TPM_ST_ACTIVE
>  4 CONSTANT TPM_ST_OWNED
> -- 
> 1.9.3