Re: [PATCH v5 12/17] tpm: remove @space from tpm_transmit()

[Stefan Berger <stefanb@linux.ibm.com>]

On 11/8/18 9:15 AM, Jarkko Sakkinen wrote:
> Remove @space from tpm_transmit() API` in order to completely remove the
> bound between low-level transmission functionality and TPM spaces. The
> only real dependency existing is the amount of data saved before trying
> to send a command to the TPM.
>
> It doesn't really matter if we save always a bit more than needed so
> this commit changes the amount saved always to be the size of the TPM
> header and three handles.
>
> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>


Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>


> ---
>   drivers/char/tpm/tpm-dev-common.c |  2 +-
>   drivers/char/tpm/tpm-interface.c  | 25 ++++++++++---------------
>   drivers/char/tpm/tpm-sysfs.c      |  5 ++---
>   drivers/char/tpm/tpm.h            | 10 +++++-----
>   drivers/char/tpm/tpm1-cmd.c       | 16 +++++++---------
>   drivers/char/tpm/tpm2-cmd.c       | 30 ++++++++++++++----------------
>   drivers/char/tpm/tpm2-space.c     |  6 ++----
>   drivers/char/tpm/tpm_vtpm_proxy.c |  2 +-
>   8 files changed, 42 insertions(+), 54 deletions(-)
>
> diff --git a/drivers/char/tpm/tpm-dev-common.c b/drivers/char/tpm/tpm-dev-common.c
> index 40c1cb09ebd2..c7dc54930576 100644
> --- a/drivers/char/tpm/tpm-dev-common.c
> +++ b/drivers/char/tpm/tpm-dev-common.c
> @@ -48,7 +48,7 @@ static ssize_t tpm_dev_transmit(struct tpm_chip *chip, struct tpm_space *space,
>   	if (ret)
>   		goto out_lock;
>
> -	len = tpm_transmit(chip, space, buf, bufsiz, TPM_TRANSMIT_UNLOCKED);
> +	len = tpm_transmit(chip, buf, bufsiz, TPM_TRANSMIT_UNLOCKED);
>   	if (len < 0)
>   		ret = len;
>
> diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
> index 7bec03e46043..8d75c103f280 100644
> --- a/drivers/char/tpm/tpm-interface.c
> +++ b/drivers/char/tpm/tpm-interface.c
> @@ -120,9 +120,7 @@ static int tpm_go_idle(struct tpm_chip *chip, unsigned int flags)
>   	return chip->ops->go_idle(chip);
>   }
>
> -static ssize_t tpm_try_transmit(struct tpm_chip *chip,
> -				struct tpm_space *space,
> -				u8 *buf, size_t bufsiz,
> +static ssize_t tpm_try_transmit(struct tpm_chip *chip, u8 *buf, size_t bufsiz,
>   				unsigned int flags)
>   {
>   	struct tpm_header *header = (void *)buf;
> @@ -192,7 +190,6 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip,
>   /**
>    * tpm_transmit - Internal kernel interface to transmit TPM commands.
>    * @chip:	a TPM chip to use
> - * @space:	a TPM space
>    * @buf:	a TPM command buffer
>    * @bufsiz:	length of the TPM command buffer
>    * @flags:	TPM transmit flags
> @@ -208,8 +205,8 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip,
>    * * The response length	- OK
>    * * -errno			- A system error
>    */
> -ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
> -		     u8 *buf, size_t bufsiz, unsigned int flags)
> +ssize_t tpm_transmit(struct tpm_chip *chip, u8 *buf, size_t bufsiz,
> +		     unsigned int flags)
>   {
>   	struct tpm_header *header = (struct tpm_header *)buf;
>   	/* space for header and handles */
> @@ -218,8 +215,7 @@ ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
>   	bool has_locality = false;
>   	u32 rc = 0;
>   	ssize_t ret;
> -	const size_t save_size = min(space ? sizeof(save) : TPM_HEADER_SIZE,
> -				     bufsiz);
> +	const size_t save_size = min(sizeof(save), bufsiz);
>   	/* the command code is where the return code will be */
>   	u32 cc = be32_to_cpu(header->return_code);
>
> @@ -249,7 +245,7 @@ ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
>   		if (ret)
>   			goto out_locality;
>
> -		ret = tpm_try_transmit(chip, space, buf, bufsiz, flags);
> +		ret = tpm_try_transmit(chip, buf, bufsiz, flags);
>
>   		/* This may fail but do not override ret. */
>   		tpm_go_idle(chip, flags);
> @@ -295,7 +291,6 @@ ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
>   /**
>    * tpm_transmit_cmd - send a tpm command to the device
>    * @chip:			a TPM chip to use
> - * @space:			a TPM space
>    * @buf:			a TPM command buffer
>    * @min_rsp_body_length:	minimum expected length of response body
>    * @flags:			TPM transmit flags
> @@ -306,15 +301,15 @@ ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
>    * * -errno	- A system error
>    * * TPM_RC	- A TPM error
>    */
> -ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_space *space,
> -			 struct tpm_buf *buf, size_t min_rsp_body_length,
> -			 unsigned int flags, const char *desc)
> +ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_buf *buf,
> +			 size_t min_rsp_body_length, unsigned int flags,
> +			 const char *desc)
>   {
>   	const struct tpm_header *header = (struct tpm_header *)buf->data;
>   	int err;
>   	ssize_t len;
>
> -	len = tpm_transmit(chip, space, buf->data, PAGE_SIZE, flags);
> +	len = tpm_transmit(chip, buf->data, PAGE_SIZE, flags);
>   	if (len <  0)
>   		return len;
>
> @@ -463,7 +458,7 @@ int tpm_send(struct tpm_chip *chip, void *cmd, size_t buflen)
>   		goto out;
>
>   	memcpy(buf.data, cmd, buflen);
> -	rc = tpm_transmit_cmd(chip, NULL, &buf, 0, 0,
> +	rc = tpm_transmit_cmd(chip, &buf, 0, 0,
>   			      "attempting to a send a command");
>   	tpm_buf_destroy(&buf);
>   out:
> diff --git a/drivers/char/tpm/tpm-sysfs.c b/drivers/char/tpm/tpm-sysfs.c
> index 928d4e839bb7..03e704f99ed6 100644
> --- a/drivers/char/tpm/tpm-sysfs.c
> +++ b/drivers/char/tpm/tpm-sysfs.c
> @@ -52,9 +52,8 @@ static ssize_t pubek_show(struct device *dev, struct device_attribute *attr,
>
>   	tpm_buf_append(&tpm_buf, anti_replay, sizeof(anti_replay));
>
> -	rc = tpm_transmit_cmd(chip, NULL, &tpm_buf,
> -			      READ_PUBEK_RESULT_MIN_BODY_SIZE, 0,
> -			      "attempting to read the PUBEK");
> +	rc = tpm_transmit_cmd(chip, &tpm_buf, READ_PUBEK_RESULT_MIN_BODY_SIZE,
> +			      0, "attempting to read the PUBEK");
>   	if (rc) {
>   		tpm_buf_destroy(&tpm_buf);
>   		return 0;
> diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
> index 68d78ebba032..10a5bcf806aa 100644
> --- a/drivers/char/tpm/tpm.h
> +++ b/drivers/char/tpm/tpm.h
> @@ -498,11 +498,11 @@ enum tpm_transmit_flags {
>   	TPM_TRANSMIT_NESTED      = BIT(1),
>   };
>
> -ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
> -		     u8 *buf, size_t bufsiz, unsigned int flags);
> -ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_space *space,
> -			 struct tpm_buf *buf, size_t min_rsp_body_length,
> -			 unsigned int flags, const char *desc);
> +ssize_t tpm_transmit(struct tpm_chip *chip, u8 *buf, size_t bufsiz,
> +		     unsigned int flags);
> +ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_buf *buf,
> +			 size_t min_rsp_body_length, unsigned int flags,
> +			 const char *desc);
>   int tpm_get_timeouts(struct tpm_chip *);
>   int tpm_auto_startup(struct tpm_chip *chip);
>
> diff --git a/drivers/char/tpm/tpm1-cmd.c b/drivers/char/tpm/tpm1-cmd.c
> index f19b7c1ff800..162c255dd131 100644
> --- a/drivers/char/tpm/tpm1-cmd.c
> +++ b/drivers/char/tpm/tpm1-cmd.c
> @@ -334,8 +334,7 @@ static int tpm1_startup(struct tpm_chip *chip)
>
>   	tpm_buf_append_u16(&buf, TPM_ST_CLEAR);
>
> -	rc = tpm_transmit_cmd(chip, NULL, &buf, 0, 0,
> -			      "attempting to start the TPM");
> +	rc = tpm_transmit_cmd(chip, &buf, 0, 0, "attempting to start the TPM");
>   	tpm_buf_destroy(&buf);
>   	return rc;
>   }
> @@ -460,7 +459,7 @@ int tpm1_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash,
>   	tpm_buf_append_u32(&buf, pcr_idx);
>   	tpm_buf_append(&buf, hash, TPM_DIGEST_SIZE);
>
> -	rc = tpm_transmit_cmd(chip, NULL, &buf, TPM_DIGEST_SIZE, 0, log_msg);
> +	rc = tpm_transmit_cmd(chip, &buf, TPM_DIGEST_SIZE, 0, log_msg);
>   	tpm_buf_destroy(&buf);
>   	return rc;
>   }
> @@ -490,7 +489,7 @@ ssize_t tpm1_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
>   		tpm_buf_append_u32(&buf, 4);
>   		tpm_buf_append_u32(&buf, subcap_id);
>   	}
> -	rc = tpm_transmit_cmd(chip, NULL, &buf, min_cap_length, 0, desc);
> +	rc = tpm_transmit_cmd(chip, &buf, min_cap_length, 0, desc);
>   	if (!rc)
>   		*cap = *(cap_t *)&buf.data[TPM_HEADER_SIZE + 4];
>   	tpm_buf_destroy(&buf);
> @@ -531,8 +530,7 @@ int tpm1_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
>   	do {
>   		tpm_buf_append_u32(&buf, num_bytes);
>
> -		rc = tpm_transmit_cmd(chip, NULL, &buf,
> -				      sizeof(out->rng_data_len), 0,
> +		rc = tpm_transmit_cmd(chip, &buf, sizeof(out->rng_data_len), 0,
>   				      "attempting get random");
>   		if (rc)
>   			goto out;
> @@ -577,7 +575,7 @@ int tpm1_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf)
>
>   	tpm_buf_append_u32(&buf, pcr_idx);
>
> -	rc = tpm_transmit_cmd(chip, NULL, &buf, TPM_DIGEST_SIZE, 0,
> +	rc = tpm_transmit_cmd(chip, &buf, TPM_DIGEST_SIZE, 0,
>   			      "attempting to read a pcr value");
>   	if (rc)
>   		goto out;
> @@ -611,7 +609,7 @@ static int tpm1_continue_selftest(struct tpm_chip *chip)
>   	if (rc)
>   		return rc;
>
> -	rc = tpm_transmit_cmd(chip, NULL, &buf, 0, 0, "continue selftest");
> +	rc = tpm_transmit_cmd(chip, &buf, 0, 0, "continue selftest");
>   	tpm_buf_destroy(&buf);
>   	return rc;
>   }
> @@ -737,7 +735,7 @@ int tpm1_pm_suspend(struct tpm_chip *chip, u32 tpm_suspend_pcr)
>   		return rc;
>   	/* now do the actual savestate */
>   	for (try = 0; try < TPM_RETRY; try++) {
> -		rc = tpm_transmit_cmd(chip, NULL, &buf, 0, 0, NULL);
> +		rc = tpm_transmit_cmd(chip, &buf, 0, 0, NULL);
>   		/*
>   		 * If the TPM indicates that it is too busy to respond to
>   		 * this command then retry before giving up.  It can take
> diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
> index ab03f8600f89..f2b0e5c52a57 100644
> --- a/drivers/char/tpm/tpm2-cmd.c
> +++ b/drivers/char/tpm/tpm2-cmd.c
> @@ -197,7 +197,7 @@ int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf)
>   	tpm_buf_append(&buf, (const unsigned char *)pcr_select,
>   		       sizeof(pcr_select));
>
> -	rc = tpm_transmit_cmd(chip, NULL, &buf, 0, 0, res_buf ?
> +	rc = tpm_transmit_cmd(chip, &buf, 0, 0, res_buf ?
>   			      "attempting to read a pcr value" : NULL);
>   	if (rc == 0 && res_buf) {
>   		out = (struct tpm2_pcr_read_out *)&buf.data[TPM_HEADER_SIZE];
> @@ -264,7 +264,7 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, u32 count,
>   		}
>   	}
>
> -	rc = tpm_transmit_cmd(chip, NULL, &buf, 0, 0,
> +	rc = tpm_transmit_cmd(chip, &buf, 0, 0,
>   			      "attempting extend a PCR value");
>
>   	tpm_buf_destroy(&buf);
> @@ -309,7 +309,7 @@ int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
>   	do {
>   		tpm_buf_reset(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_RANDOM);
>   		tpm_buf_append_u16(&buf, num_bytes);
> -		err = tpm_transmit_cmd(chip, NULL, &buf,
> +		err = tpm_transmit_cmd(chip, &buf,
>   				       offsetof(struct tpm2_get_random_out,
>   						buffer),
>   				       0, "attempting get random");
> @@ -362,7 +362,7 @@ void tpm2_flush_context_cmd(struct tpm_chip *chip, u32 handle,
>
>   	tpm_buf_append_u32(&buf, handle);
>
> -	tpm_transmit_cmd(chip, NULL, &buf, 0, flags, "flushing context");
> +	tpm_transmit_cmd(chip, &buf, 0, flags, "flushing context");
>   	tpm_buf_destroy(&buf);
>   }
>
> @@ -476,7 +476,7 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
>   		goto out;
>   	}
>
> -	rc = tpm_transmit_cmd(chip, NULL, &buf, 4, 0, "sealing data");
> +	rc = tpm_transmit_cmd(chip, &buf, 4, 0, "sealing data");
>   	if (rc)
>   		goto out;
>
> @@ -558,7 +558,7 @@ static int tpm2_load_cmd(struct tpm_chip *chip,
>   		goto out;
>   	}
>
> -	rc = tpm_transmit_cmd(chip, NULL, &buf, 4, flags, "loading blob");
> +	rc = tpm_transmit_cmd(chip, &buf, 4, flags, "loading blob");
>   	if (!rc)
>   		*blob_handle = be32_to_cpup(
>   			(__be32 *) &buf.data[TPM_HEADER_SIZE]);
> @@ -608,7 +608,7 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
>   			     options->blobauth /* hmac */,
>   			     TPM_DIGEST_SIZE);
>
> -	rc = tpm_transmit_cmd(chip, NULL, &buf, 6, flags, "unsealing");
> +	rc = tpm_transmit_cmd(chip, &buf, 6, flags, "unsealing");
>   	if (rc > 0)
>   		rc = -EPERM;
>
> @@ -698,7 +698,7 @@ ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,  u32 *value,
>   	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, 0, 0, NULL);
> +	rc = tpm_transmit_cmd(chip, &buf, 0, 0, NULL);
>   	if (!rc) {
>   		out = (struct tpm2_get_cap_out *)
>   			&buf.data[TPM_HEADER_SIZE];
> @@ -728,7 +728,7 @@ void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
>   	if (rc)
>   		return;
>   	tpm_buf_append_u16(&buf, shutdown_type);
> -	tpm_transmit_cmd(chip, NULL, &buf, 0, 0, "stopping the TPM");
> +	tpm_transmit_cmd(chip, &buf, 0, 0, "stopping the TPM");
>   	tpm_buf_destroy(&buf);
>   }
>
> @@ -757,7 +757,7 @@ static int tpm2_do_selftest(struct tpm_chip *chip)
>   			return rc;
>
>   		tpm_buf_append_u8(&buf, full);
> -		rc = tpm_transmit_cmd(chip, NULL, &buf, 0, 0,
> +		rc = tpm_transmit_cmd(chip, &buf, 0, 0,
>   				      "attempting the self test");
>   		tpm_buf_destroy(&buf);
>
> @@ -794,7 +794,7 @@ int tpm2_probe(struct tpm_chip *chip)
>   	tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
>   	tpm_buf_append_u32(&buf, TPM_PT_TOTAL_COMMANDS);
>   	tpm_buf_append_u32(&buf, 1);
> -	rc = tpm_transmit_cmd(chip, NULL, &buf, 0, 0, NULL);
> +	rc = tpm_transmit_cmd(chip, &buf, 0, 0, NULL);
>   	/* We ignore TPM return codes on purpose. */
>   	if (rc >=  0) {
>   		out = (struct tpm_header *)buf.data;
> @@ -833,8 +833,7 @@ static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
>   	tpm_buf_append_u32(&buf, 0);
>   	tpm_buf_append_u32(&buf, 1);
>
> -	rc = tpm_transmit_cmd(chip, NULL, &buf, 9, 0,
> -			      "get tpm pcr allocation");
> +	rc = tpm_transmit_cmd(chip, &buf, 9, 0, "get tpm pcr allocation");
>   	if (rc)
>   		goto out;
>
> @@ -905,7 +904,7 @@ static int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip)
>   	tpm_buf_append_u32(&buf, TPM2_CC_FIRST);
>   	tpm_buf_append_u32(&buf, nr_commands);
>
> -	rc = tpm_transmit_cmd(chip, NULL, &buf, 9 + 4 * nr_commands, 0, NULL);
> +	rc = tpm_transmit_cmd(chip, &buf, 9 + 4 * nr_commands, 0, NULL);
>   	if (rc) {
>   		tpm_buf_destroy(&buf);
>   		goto out;
> @@ -962,8 +961,7 @@ static int tpm2_startup(struct tpm_chip *chip)
>   		return rc;
>
>   	tpm_buf_append_u16(&buf, TPM2_SU_CLEAR);
> -	rc = tpm_transmit_cmd(chip, NULL, &buf, 0, 0,
> -			      "attempting to start the TPM");
> +	rc = tpm_transmit_cmd(chip, &buf, 0, 0, "attempting to start the TPM");
>   	tpm_buf_destroy(&buf);
>
>   	return rc;
> diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c
> index 9c009db15f88..d1c371db1ab7 100644
> --- a/drivers/char/tpm/tpm2-space.c
> +++ b/drivers/char/tpm/tpm2-space.c
> @@ -83,8 +83,7 @@ static int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
>   	body_size = sizeof(*ctx) + be16_to_cpu(ctx->blob_size);
>   	tpm_buf_append(&tbuf, &buf[*offset], body_size);
>
> -	rc = tpm_transmit_cmd(chip, NULL, &tbuf, 4,
> -			      TPM_TRANSMIT_UNLOCKED, NULL);
> +	rc = tpm_transmit_cmd(chip, &tbuf, 4, TPM_TRANSMIT_UNLOCKED, NULL);
>   	if (rc < 0) {
>   		dev_warn(&chip->dev, "%s: failed with a system error %d\n",
>   			 __func__, rc);
> @@ -132,8 +131,7 @@ static int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 *buf,
>
>   	tpm_buf_append_u32(&tbuf, handle);
>
> -	rc = tpm_transmit_cmd(chip, NULL, &tbuf, 0,
> -			      TPM_TRANSMIT_UNLOCKED, NULL);
> +	rc = tpm_transmit_cmd(chip, &tbuf, 0, TPM_TRANSMIT_UNLOCKED, NULL);
>   	if (rc < 0) {
>   		dev_warn(&chip->dev, "%s: failed with a system error %d\n",
>   			 __func__, rc);
> diff --git a/drivers/char/tpm/tpm_vtpm_proxy.c b/drivers/char/tpm/tpm_vtpm_proxy.c
> index 28eb5ab15b99..e8a1da2810a9 100644
> --- a/drivers/char/tpm/tpm_vtpm_proxy.c
> +++ b/drivers/char/tpm/tpm_vtpm_proxy.c
> @@ -417,7 +417,7 @@ static int vtpm_proxy_request_locality(struct tpm_chip *chip, int locality)
>
>   	proxy_dev->state |= STATE_DRIVER_COMMAND;
>
> -	rc = tpm_transmit_cmd(chip, NULL, &buf, 0, TPM_TRANSMIT_NESTED,
> +	rc = tpm_transmit_cmd(chip, &buf, 0, TPM_TRANSMIT_NESTED,
>   			      "attempting to set locality");
>
>   	proxy_dev->state &= ~STATE_DRIVER_COMMAND;