Add support for the TPM2_GetCapability command.
Change the command file and the help accordingly.
Signed-off-by: Miquel Raynal miquel.raynal@bootlin.com --- cmd/tpm-v2.c | 41 +++++++++++++++++++++++++++++++++++++++++ include/tpm-v2.h | 15 +++++++++++++++ lib/tpm-v2.c | 25 +++++++++++++++++++++++++ 3 files changed, 81 insertions(+)
diff --git a/cmd/tpm-v2.c b/cmd/tpm-v2.c index a61d751b4a..39fd9f0064 100644 --- a/cmd/tpm-v2.c +++ b/cmd/tpm-v2.c @@ -108,6 +108,39 @@ static int do_tpm_pcr_read(cmd_tbl_t *cmdtp, int flag, int argc, return report_return_code(rc); }
+static int do_tpm_get_capability(cmd_tbl_t *cmdtp, int flag, int argc, + char * const argv[]) +{ + u32 capability, property, rc; + u8 *data; + size_t count; + int i, j; + + if (argc != 5) + return CMD_RET_USAGE; + + capability = simple_strtoul(argv[1], NULL, 0); + property = simple_strtoul(argv[2], NULL, 0); + data = (void *)simple_strtoul(argv[3], NULL, 0); + count = simple_strtoul(argv[4], NULL, 0); + + rc = tpm2_get_capability(capability, property, data, count); + if (!rc) { + printf("Capabilities read from TPM:\n"); + for (i = 0; i < count; i++) { + printf("Property 0x"); + for (j = 0; j < 4; j++) + printf("%02x", data[(i * 8) + j]); + printf(": 0x"); + for (j = 4; j < 8; j++) + printf("%02x", data[(i * 8) + j]); + printf("\n"); + } + } + + return report_return_code(rc); +} + static cmd_tbl_t tpm2_commands[] = { U_BOOT_CMD_MKENT(info, 0, 1, do_tpm_info, "", ""), U_BOOT_CMD_MKENT(init, 0, 1, do_tpm_init, "", ""), @@ -116,6 +149,7 @@ static cmd_tbl_t tpm2_commands[] = { U_BOOT_CMD_MKENT(clear, 0, 1, do_tpm2_clear, "", ""), U_BOOT_CMD_MKENT(pcr_extend, 0, 1, do_tpm2_pcr_extend, "", ""), U_BOOT_CMD_MKENT(pcr_read, 0, 1, do_tpm_pcr_read, "", ""), + U_BOOT_CMD_MKENT(get_capability, 0, 1, do_tpm_get_capability, "", ""), };
cmd_tbl_t *get_tpm_commands(unsigned int *size) @@ -155,4 +189,11 @@ U_BOOT_CMD(tpm, CONFIG_SYS_MAXARGS, 1, do_tpm, "Issue a TPMv2.x command", " Read PCR #<pcr> to memory address <digest_addr>.\n" " <pcr>: index of the PCR\n" " <digest_addr>: address to store the a 32-byte SHA256 digest\n" +"get_capability <capability> <property> <addr> <count>\n" +" Read and display <count> entries indexed by <capability>/<property>.\n" +" Values are 4-byte long and are written at <addr>.\n" +" <capability>: capability\n" +" <property>: property\n" +" <addr>: address to store <count> entries of 4 bytes\n" +" <count>: number of entries to retrieve\n" ); diff --git a/include/tpm-v2.h b/include/tpm-v2.h index 54d14df365..07cd3a5e99 100644 --- a/include/tpm-v2.h +++ b/include/tpm-v2.h @@ -175,4 +175,19 @@ u32 tpm2_pcr_extend(u32 index, const uint8_t *digest); */ u32 tpm2_pcr_read(u32 index, void *data, unsigned int *updates);
+/** + * Issue a TPM2_GetCapability command. This implementation is limited + * to query property index that is 4-byte wide. + * + * @param capability Partition of capabilities + * @param property Further definition of capability, which is + * limited to be 4-byte wide + * @param buf Output buffer for capability information + * @param prop_count Size of output buffer + * + * @return return code of the operation + */ +u32 tpm2_get_capability(u32 capability, u32 property, void *buf, + size_t prop_count); + #endif /* __TPM_V2_H */ diff --git a/lib/tpm-v2.c b/lib/tpm-v2.c index d557b08f8b..c567c943df 100644 --- a/lib/tpm-v2.c +++ b/lib/tpm-v2.c @@ -158,3 +158,28 @@ u32 tpm2_pcr_read(u32 index, void *data, unsigned int *updates)
return 0; } + +u32 tpm2_get_capability(u32 capability, u32 property, void *buf, + size_t prop_count) +{ + u8 command_v2[COMMAND_BUFFER_SIZE] = { + tpm_u16(TPM2_ST_NO_SESSIONS), /* TAG */ + tpm_u32(22), /* Length */ + tpm_u32(TPM2_CC_GET_CAPABILITY), /* Command code */ + + tpm_u32(capability), /* Capability */ + tpm_u32(property), /* Property */ + tpm_u32(prop_count), /* Property count */ + }; + u8 response[COMMAND_BUFFER_SIZE]; + size_t response_len = COMMAND_BUFFER_SIZE; + int ret; + + ret = tpm_sendrecv_command(command_v2, response, &response_len); + if (ret) + return ret; + + memcpy(buf, &response[19], response_len - 19); + + return 0; +}