A following patch introduces EFI_TCG2_PROTOCOL.
One of the functions of that protocol is GetCapability().
In order to parse device capabilities we need to access a u32
before the properties which the current implementation ignores
while reading device properties.
So let's make the response length configurable and prepare the
functions for EFI_TCG2_PROTOCOL.
Signed-off-by: Ilias Apalodimas <ilias.apalodi...@linaro.org>
---
cmd/tpm-v2.c | 2 +-
include/tpm-v2.h | 12 +++++++-----
lib/tpm-v2.c | 10 +++++++---
3 files changed, 15 insertions(+), 9 deletions(-)
diff --git a/cmd/tpm-v2.c b/cmd/tpm-v2.c
index e6742656f578..c2df1c34043a 100644
--- a/cmd/tpm-v2.c
+++ b/cmd/tpm-v2.c
@@ -183,7 +183,7 @@ static int do_tpm_get_capability(struct cmd_tbl *cmdtp, int
flag, int argc,
data = map_sysmem(simple_strtoul(argv[3], NULL, 0), 0);
count = simple_strtoul(argv[4], NULL, 0);
- rc = tpm2_get_capability(dev, capability, property, data, count);
+ rc = tpm2_get_capability(dev, capability, property, data, count, false);
if (rc)
goto unmap_data;
diff --git a/include/tpm-v2.h b/include/tpm-v2.h
index f6c045d35480..ee74028ca83b 100644
--- a/include/tpm-v2.h
+++ b/include/tpm-v2.h
@@ -257,15 +257,17 @@ u32 tpm2_pcr_read(struct udevice *dev, u32 idx, unsigned
int idx_min_sz,
* to query property index that is 4-byte wide.
*
* @dev TPM device
- * @capability Partition of capabilities
- * @property Further definition of capability, limited to be 4 bytes wide
- * @buf Output buffer for capability information
- * @prop_count Size of output buffer
+ * @capability Partition of capabilities
+ * @property Further definition of capability, limited to be 4 bytes
+ * wide
+ * @buf Output buffer for capability information
+ * @prop_count Size of output buffer
+ * @get_count Include tpmu property count
*
* @return code of the operation
*/
u32 tpm2_get_capability(struct udevice *dev, u32 capability, u32 property,
- void *buf, size_t prop_count);
+ void *buf, size_t prop_count, bool get_count);
/**
* Issue a TPM2_DictionaryAttackLockReset command.
diff --git a/lib/tpm-v2.c b/lib/tpm-v2.c
index a4c352e3ef75..b58c1057995b 100644
--- a/lib/tpm-v2.c
+++ b/lib/tpm-v2.c
@@ -161,7 +161,7 @@ u32 tpm2_pcr_read(struct udevice *dev, u32 idx, unsigned
int idx_min_sz,
}
u32 tpm2_get_capability(struct udevice *dev, u32 capability, u32 property,
- void *buf, size_t prop_count)
+ void *buf, size_t prop_count, bool get_count)
{
u8 command_v2[COMMAND_BUFFER_SIZE] = {
tpm_u16(TPM2_ST_NO_SESSIONS), /* TAG */
@@ -181,13 +181,17 @@ u32 tpm2_get_capability(struct udevice *dev, u32
capability, u32 property,
if (ret)
return ret;
+ /* When reading PCR properties we need the count */
+ properties_off = sizeof(u16) + sizeof(u32) + sizeof(u32) +
+ sizeof(u8) + sizeof(u32);
/*
* In the response buffer, the properties are located after the:
* tag (u16), response size (u32), response code (u32),
* YES/NO flag (u8), TPM_CAP (u32) and TPMU_CAPABILITIES (u32).
*/
- properties_off = sizeof(u16) + sizeof(u32) + sizeof(u32) +
- sizeof(u8) + sizeof(u32) + sizeof(u32);
+ if (!get_count)
+ properties_off += sizeof(u32);
+
memcpy(buf, &response[properties_off], response_len - properties_off);
return 0;
--
2.29.2
