diff options
Diffstat (limited to 'firmware/lib/tpm2_lite/tlcl.c')
-rw-r--r-- | firmware/lib/tpm2_lite/tlcl.c | 49 |
1 files changed, 48 insertions, 1 deletions
diff --git a/firmware/lib/tpm2_lite/tlcl.c b/firmware/lib/tpm2_lite/tlcl.c index bb212d24..89bf25a7 100644 --- a/firmware/lib/tpm2_lite/tlcl.c +++ b/firmware/lib/tpm2_lite/tlcl.c @@ -523,7 +523,25 @@ uint32_t TlclGetRandom(uint8_t *data, uint32_t length, uint32_t *size) return TPM_E_IOERROR; } -uint32_t TlclGetVersion(uint32_t* vendor, uint64_t* firmware_version) +// Converts TPM_PT_VENDOR_STRING_x |value| to an array of bytes in |buf|. +// Returns the number of bytes in the array. +// |buf| should be at least 4 bytes long. +size_t tlcl_vendor_string_parse(uint32_t value, uint8_t* buf) +{ + size_t len = 0; + int shift = 24; + for (; len < 4; shift -= 8) { + uint8_t byte = (value >> shift) & 0xffu; + if (!byte) + break; + buf[len++] = byte; + } + return len; +} + +uint32_t TlclGetVersion(uint32_t* vendor, uint64_t* firmware_version, + uint8_t* vendor_specific_buf, + size_t* vendor_specific_buf_size) { uint32_t result = tlcl_get_tpm_property(TPM_PT_MANUFACTURER, vendor); if (result != TPM_SUCCESS) @@ -539,6 +557,35 @@ uint32_t TlclGetVersion(uint32_t* vendor, uint64_t* firmware_version) return result; *firmware_version = ((uint64_t) version_1 << 32) | version_2; + + if (!vendor_specific_buf_size) + return TPM_SUCCESS; + + size_t total_size = 0; + uint32_t prop_id; + uint8_t prop_string[16]; + for (prop_id = TPM_PT_VENDOR_STRING_1; + prop_id <= TPM_PT_VENDOR_STRING_4; + ++prop_id) { + uint32_t prop_value; + result = tlcl_get_tpm_property(prop_id, &prop_value); + if (result != TPM_SUCCESS) + break; + + size_t prop_len = tlcl_vendor_string_parse( + prop_value, prop_string + total_size); + VbAssert(prop_len <= 4 && + total_size + prop_len <= sizeof(prop_string)); + total_size += prop_len; + if (prop_len < 4) + break; + } + if (vendor_specific_buf) { + if (total_size > *vendor_specific_buf_size) + total_size = *vendor_specific_buf_size; + memcpy(vendor_specific_buf, prop_string, total_size); + } + *vendor_specific_buf_size = total_size; return TPM_SUCCESS; } |