[U-Boot] [PATCH v2 2/5] tpm: fix reading of permanent flags

André Draszik
2017-10-03T15:55:51Z

From: André Draszik <adraszik@tycoint.com>

The offset of the permanent flags structure is in a different
place in the response compared to what the code is doing,
which gives us a completely useless result.

Fix by replacing hand-crafted code with generic parser
infrastructure.

Signed-off-by: André Draszik <adraszik@tycoint.com>
---
lib/tpm.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/lib/tpm.c b/lib/tpm.c
index d1cf5a8a16..5659fa5e18 100644
--- a/lib/tpm.c
+++ b/lib/tpm.c
@@ -607,14 +607,24 @@ uint32_t tpm_get_permanent_flags(struct tpm_permanent_flags *pflags)
0x0, 0x0, 0x0, 0x4, /* subcap size */
0x0, 0x0, 0x1, 0x8, /* subcap value */
};
+ const size_t data_size_offset = TPM_HEADER_SIZE;
+ const size_t data_offset = TPM_HEADER_SIZE + sizeof (uint32_t);
uint8_t response[COMMAND_BUFFER_SIZE];
size_t response_length = sizeof(response);
uint32_t err;
+ uint32_t data_size;

err = tpm_sendrecv_command(command, response, &response_length);
if (err)
return err;
- memcpy(pflags, response + TPM_HEADER_SIZE, sizeof(*pflags));
+ if (unpack_byte_string(response, response_length, "d",
+ data_size_offset, &data_size))
+ return TPM_LIB_ERROR;
+ if (data_size < sizeof(*pflags))
+ return TPM_LIB_ERROR;
+ if (unpack_byte_string(response, response_length, "s",
+ data_offset, pflags, sizeof(*pflags)))
+ return TPM_LIB_ERROR;

return 0;
}
--
2.14.2