[U-Boot] [PATCH v2 06/18] lib: tpm: Add command to flush resources
Stefan Roese
sr at denx.de
Wed Jan 18 17:07:30 CET 2017
On 11.01.2017 16:00, Mario Six wrote:
> This patch adds a function to the TPM library, which allows U-Boot to
> flush resources, e.g. keys, from the TPM.
>
> Signed-off-by: Mario Six <mario.six at gdsys.cc>
> ---
> Changes in v2:
>
> * Added U-Boot command for resource flushing ("tpm flush"), and made the
> command and the library function deactivate-able via config
> ---
> board/gdsys/p1022/controlcenterd-id.c | 9 -----
> cmd/tpm.c | 70 +++++++++++++++++++++++++++++++++++
> drivers/tpm/Kconfig | 6 +++
> include/tpm.h | 45 ++++++++++++++++++++++
> lib/tpm.c | 29 +++++++++++++++
> 5 files changed, 150 insertions(+), 9 deletions(-)
>
> diff --git a/board/gdsys/p1022/controlcenterd-id.c b/board/gdsys/p1022/controlcenterd-id.c
> index 2c6c698..1648f13 100644
> --- a/board/gdsys/p1022/controlcenterd-id.c
> +++ b/board/gdsys/p1022/controlcenterd-id.c
> @@ -43,15 +43,6 @@
> #define CCDM_AUTO_FIRST_STAGE
> #endif
>
> -/* enums from TCG specs */
> -enum {
> - /* capability areas */
> - TPM_CAP_NV_INDEX = 0x00000011,
> - TPM_CAP_HANDLE = 0x00000014,
> - /* resource types */
> - TPM_RT_KEY = 0x00000001,
> -};
> -
> /* CCDM specific contants */
> enum {
> /* NV indices */
> diff --git a/cmd/tpm.c b/cmd/tpm.c
> index 312503f..625fc43 100644
> --- a/cmd/tpm.c
> +++ b/cmd/tpm.c
> @@ -646,6 +646,64 @@ TPM_COMMAND_NO_ARG(tpm_end_oiap)
>
> #endif /* CONFIG_TPM_AUTH_SESSIONS */
>
> +#ifdef CONFIG_TPM_FLUSH_RESOURCES
> +static int do_tpm_flush(cmd_tbl_t *cmdtp, int flag, int argc,
> + char * const argv[])
> +{
> + int type = 0;
> +
> + if (argc != 2)
> + return CMD_RET_USAGE;
> +
> + if (strcasecmp(argv[1], "key"))
> + type = TPM_RT_KEY;
> + else if (strcasecmp(argv[1], "auth"))
> + type = TPM_RT_AUTH;
> + else if (strcasecmp(argv[1], "hash"))
> + type = TPM_RT_HASH;
> + else if (strcasecmp(argv[1], "trans"))
> + type = TPM_RT_TRANS;
> + else if (strcasecmp(argv[1], "context"))
> + type = TPM_RT_CONTEXT;
> + else if (strcasecmp(argv[1], "counter"))
> + type = TPM_RT_COUNTER;
> + else if (strcasecmp(argv[1], "delegate"))
> + type = TPM_RT_DELEGATE;
> + else if (strcasecmp(argv[1], "daa_tpm"))
> + type = TPM_RT_DAA_TPM;
> + else if (strcasecmp(argv[1], "daa_v0"))
> + type = TPM_RT_DAA_V0;
> + else if (strcasecmp(argv[1], "daa_v1"))
> + type = TPM_RT_DAA_V1;
> +
> + if (strcasecmp(argv[2], "all")) {
> + uint16_t res_count;
> + uint8_t buf[288];
> + uint8_t *ptr;
> + int err;
> + uint i;
> +
> + /* fetch list of already loaded resources in the TPM */
> + err = tpm_get_capability(TPM_CAP_HANDLE, type, buf,
> + sizeof(buf));
> + if (err)
> + return -1;
> + res_count = get_unaligned_be16(buf);
> + ptr = buf + 2;
> + for (i = 0; i < res_count; ++i, ptr += 4)
> + tpm_flush_specific(get_unaligned_be32(ptr), type);
> + } else {
> + uint32_t handle = simple_strtoul(argv[2], NULL, 0);
> +
> + if (!handle)
> + return -1;
> + tpm_flush_specific(cpu_to_be32(handle), type);
> + }
> +
> + return 0;
> +}
> +#endif /* CONFIG_TPM_FLUSH_RESOURCES */
> +
> #define MAKE_TPM_CMD_ENTRY(cmd) \
> U_BOOT_CMD_MKENT(cmd, 0, 1, do_tpm_ ## cmd, "", "")
>
> @@ -701,6 +759,10 @@ static cmd_tbl_t tpm_commands[] = {
> U_BOOT_CMD_MKENT(get_pub_key_oiap, 0, 1,
> do_tpm_get_pub_key_oiap, "", ""),
> #endif /* CONFIG_TPM_AUTH_SESSIONS */
> +#ifdef CONFIG_TPM_FLUSH_RESOURCES
> + U_BOOT_CMD_MKENT(flush, 0, 1,
> + do_tpm_flush, "", ""),
> +#endif /* CONFIG_TPM_FLUSH_RESOURCES */
> };
>
> static int do_tpm(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
> @@ -750,6 +812,14 @@ U_BOOT_CMD(tpm, CONFIG_SYS_MAXARGS, 1, do_tpm,
> " get_capability cap_area sub_cap addr count\n"
> " - Read <count> bytes of TPM capability indexed by <cap_area> and\n"
> " <sub_cap> to memory address <addr>.\n"
> +#ifdef CONFIG_TPM_FLUSH_RESOURCES
> +"Resource management functions\n"
> +" flush resource_type id\n"
> +" - flushes a resource of type <resource_type> (may be one of key, auth,\n"
> +" hash, trans, context, counter, delegate, daa_tpm, daa_v0, daa_v1),\n"
> +" and id <id> from the TPM. Use an <id> of \"all\" to flush all\n"
> +" resources of that type.\n"
> +#endif /* CONFIG_TPM_FLUSH_RESOURCES */
> #ifdef CONFIG_TPM_AUTH_SESSIONS
> "Storage functions\n"
> " loadkey2_oiap parent_handle key_addr key_len usage_auth\n"
> diff --git a/drivers/tpm/Kconfig b/drivers/tpm/Kconfig
> index 7ab34ce..3490ee0 100644
> --- a/drivers/tpm/Kconfig
> +++ b/drivers/tpm/Kconfig
> @@ -82,4 +82,10 @@ config TPM_ST33ZP24_SPI
> to the device using the standard TPM Interface Specification (TIS)
> protocol
>
> +config TPM_FLUSH_RESOURCES
> + bool "Enable TPM resource flushing support"
> + depends on TPM
> + help
> + Enable support to flush specific resources (e.g. keys) from the TPM.
> + The functionality is available via the 'tpm' command as well.
> endmenu
> diff --git a/include/tpm.h b/include/tpm.h
> index 9a6585d..800f29c 100644
> --- a/include/tpm.h
> +++ b/include/tpm.h
> @@ -47,6 +47,42 @@ enum tpm_nv_index {
> TPM_NV_INDEX_DIR = 0x10000001,
> };
>
> +enum tpm_resource_type {
> + TPM_RT_KEY = 0x00000001,
> + TPM_RT_AUTH = 0x00000002,
> + TPM_RT_HASH = 0x00000003,
> + TPM_RT_TRANS = 0x00000004,
> + TPM_RT_CONTEXT = 0x00000005,
> + TPM_RT_COUNTER = 0x00000006,
> + TPM_RT_DELEGATE = 0x00000007,
> + TPM_RT_DAA_TPM = 0x00000008,
> + TPM_RT_DAA_V0 = 0x00000009,
> + TPM_RT_DAA_V1 = 0x0000000A,
> +};
> +
> +enum tpm_capability_areas {
> + TPM_CAP_ORD = 0x00000001,
> + TPM_CAP_ALG = 0x00000002,
> + TPM_CAP_PID = 0x00000003,
> + TPM_CAP_FLAG = 0x00000004,
> + TPM_CAP_PROPERTY = 0x00000005,
> + TPM_CAP_VERSION = 0x00000006,
> + TPM_CAP_KEY_HANDLE = 0x00000007,
> + TPM_CAP_CHECK_LOADED = 0x00000008,
> + TPM_CAP_SYM_MODE = 0x00000009,
> + TPM_CAP_KEY_STATUS = 0x0000000C,
> + TPM_CAP_NV_LIST = 0x0000000D,
> + TPM_CAP_MFR = 0x00000010,
> + TPM_CAP_NV_INDEX = 0x00000011,
> + TPM_CAP_TRANS_ALG = 0x00000012,
> + TPM_CAP_HANDLE = 0x00000014,
> + TPM_CAP_TRANS_ES = 0x00000015,
> + TPM_CAP_AUTH_ENCRYPT = 0x00000017,
> + TPM_CAP_SELECT_SIZE = 0x00000018,
> + TPM_CAP_DA_LOGIC = 0x00000019,
> + TPM_CAP_VERSION_VAL = 0x0000001A,
> +};
> +
> #define TPM_NV_PER_GLOBALLOCK (1U << 15)
> #define TPM_NV_PER_PPWRITE (1U << 0)
> #define TPM_NV_PER_READ_STCLEAR (1U << 31)
> @@ -594,4 +630,13 @@ uint32_t tpm_get_permanent_flags(struct tpm_permanent_flags *pflags);
> */
> uint32_t tpm_get_permissions(uint32_t index, uint32_t *perm);
>
> +/**
> + * Flush a resource with a given handle and type from the TPM
> + *
> + * @param key_handle handle of the resource
> + * @param resource_type type of the resource
> + * @return return code of the operation
> + */
> +uint32_t tpm_flush_specific(uint32_t key_handle, uint32_t resource_type);
> +
> #endif /* __TPM_H */
> diff --git a/lib/tpm.c b/lib/tpm.c
> index 88f2406..fb12214 100644
> --- a/lib/tpm.c
> +++ b/lib/tpm.c
> @@ -645,6 +645,35 @@ uint32_t tpm_get_permissions(uint32_t index, uint32_t *perm)
> return 0;
> }
>
> +#ifdef CONFIG_TPM_FLUSH_RESOURCES
> +uint32_t tpm_flush_specific(uint32_t key_handle, uint32_t resource_type)
> +{
> + const uint8_t command[18] = {
> + 0x00, 0xc1, /* TPM_TAG */
> + 0x00, 0x00, 0x00, 0x12, /* parameter size */
> + 0x00, 0x00, 0x00, 0xba, /* TPM_COMMAND_CODE */
> + 0x00, 0x00, 0x00, 0x00, /* key handle */
> + 0x00, 0x00, 0x00, 0x00, /* resource type */
> + };
> + const size_t key_handle_offset = 10;
> + const size_t resource_type_offset = 14;
> + uint8_t buf[COMMAND_BUFFER_SIZE], response[COMMAND_BUFFER_SIZE];
> + size_t response_length = sizeof(response);
> + uint32_t err;
> +
> + if (pack_byte_string(buf, sizeof(buf), "sdd",
> + 0, command, sizeof(command),
> + key_handle_offset, key_handle,
> + resource_type_offset, resource_type))
> + return TPM_LIB_ERROR;
> +
> + err = tpm_sendrecv_command(buf, response, &response_length);
> + if (err)
> + return err;
> + return 0;
> +}
You don't need "err" here. Simpler is this version:
return tpm_sendrecv_command(buf, response, &response_length);
Other than this:
Reviewed-by: Stefan Roese <sr at denx.de>
Thanks,
Stefan
More information about the U-Boot
mailing list