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

Jarkko Sakkinen
2018-03-26T12:14:05Z

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@linux.intel.com>
---
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