Re: [PATCH v4 3/4] tpm: migrate tpm2_get_tpm_pt() to use struct tpm_buf

[Jerry Snitselaar]

On Mon Mar 26 18, Jarkko Sakkinen wrote:
> In order to make struct tpm_buf the first class object for constructing TPM
> commands, migrate tpm2_get_tpm_pt() to use it.
>
> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>

Reviewed-by: Jerry Snitselaar <jsnitsel@xxxxxxxxxx>

> ---
> drivers/char/tpm/tpm2-cmd.c | 63 +++++++++++++++++----------------------------
> 1 file changed, 23 insertions(+), 40 deletions(-)
>
> diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
> index 7bffd0fd1dca..b3b52f9eb65f 100644
> --- a/drivers/char/tpm/tpm2-cmd.c
> +++ b/drivers/char/tpm/tpm2-cmd.c
> @@ -27,20 +27,6 @@ enum tpm2_session_attributes {
> 	TPM2_SA_CONTINUE_SESSION	= BIT(0),
> };
>
> -struct tpm2_get_tpm_pt_in {
> -	__be32	cap_id;
> -	__be32	property_id;
> -	__be32	property_cnt;
> -} __packed;
> -
> -struct tpm2_get_tpm_pt_out {
> -	u8	more_data;
> -	__be32	subcap_id;
> -	__be32	property_cnt;
> -	__be32	property_id;
> -	__be32	value;
> -} __packed;
> -
> struct tpm2_get_random_in {
> 	__be16	size;
> } __packed;
> @@ -51,8 +37,6 @@ struct tpm2_get_random_out {
> } __packed;
>
> union tpm2_cmd_params {
> -	struct	tpm2_get_tpm_pt_in	get_tpm_pt_in;
> -	struct	tpm2_get_tpm_pt_out	get_tpm_pt_out;
> 	struct	tpm2_get_random_in	getrandom_in;
> 	struct	tpm2_get_random_out	getrandom_out;
> };
> @@ -379,19 +363,6 @@ int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max)
> 	return total ? total : -EIO;
> }
>
> -#define TPM2_GET_TPM_PT_IN_SIZE \
> -	(sizeof(struct tpm_input_header) + \
> -	 sizeof(struct tpm2_get_tpm_pt_in))
> -
> -#define TPM2_GET_TPM_PT_OUT_BODY_SIZE \
> -	 sizeof(struct tpm2_get_tpm_pt_out)
> -
> -static const struct tpm_input_header tpm2_get_tpm_pt_header = {
> -	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
> -	.length = cpu_to_be32(TPM2_GET_TPM_PT_IN_SIZE),
> -	.ordinal = cpu_to_be32(TPM2_CC_GET_CAPABILITY)
> -};
> -
> /**
>  * tpm2_flush_context_cmd() - execute a TPM2_FlushContext command
>  * @chip: TPM chip to use
> @@ -725,6 +696,14 @@ int tpm2_unseal_trusted(struct tpm_chip *chip,
> 	return rc;
> }
>
> +struct tpm2_get_cap_out {
> +	u8 more_data;
> +	__be32 subcap_id;
> +	__be32 property_cnt;
> +	__be32 property_id;
> +	__be32 value;
> +} __packed;
> +
> /**
>  * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type property
>  * @chip:		TPM chip to use.
> @@ -737,19 +716,23 @@ int tpm2_unseal_trusted(struct tpm_chip *chip,
> ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,  u32 *value,
> 			const char *desc)
> {
> -	struct tpm2_cmd cmd;
> +	struct tpm2_get_cap_out *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(property_id);
> -	cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
> -
> -	rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd),
> -			      TPM2_GET_TPM_PT_OUT_BODY_SIZE, 0, desc);
> -	if (!rc)
> -		*value = be32_to_cpu(cmd.params.get_tpm_pt_out.value);
> -
> +	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
> +	if (rc)
> +		return rc;
> +	tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
> +	tpm_buf_append_u32(&buf, property_id);
> +	tpm_buf_append_u32(&buf, 1);
> +	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0, NULL);
> +	if (!rc) {
> +		out = (struct tpm2_get_cap_out *)
> +			&buf.data[TPM_HEADER_SIZE];
> +		*value = be32_to_cpu(out->value);
> +	}
> +	tpm_buf_destroy(&buf);
> 	return rc;
> }
> EXPORT_SYMBOL_GPL(tpm2_get_tpm_pt);
> --
> 2.15.1