On 04.11.20 14:47, Ilias Apalodimas wrote:
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.apalodimas@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)
The implementation would be more stable if we would derive the offset from field property instead of adding get_count.
{ u8 command_v2[COMMAND_BUFFER_SIZE] = {
Shouldn't COMMAND_BUFFER_SIZE be changed to something with TPM in the name, e.g TPM_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).
This comment should be above 'properties_off ='. 'get_count' related field should be mentioned.
Best regards
Heinrich
- 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;