From a557d258c6be49ec1253947a227189de149971df Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Tue, 30 Aug 2022 21:05:32 -0600 Subject: tpm: Require a digest source when extending the PCR This feature is used for measured boot, so we can add a log entry to the TCPA with some information about where the digest comes from. It is not currently supported in the TPM drivers, but add it to the API so that code which expects it can signal its request. Signed-off-by: Simon Glass Reviewed-by: Ilias Apalodimas Signed-off-by: Ilias Apalodimas --- include/tpm_api.h | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'include') diff --git a/include/tpm_api.h b/include/tpm_api.h index 11aa14eb793..8979d9d6df7 100644 --- a/include/tpm_api.h +++ b/include/tpm_api.h @@ -81,14 +81,16 @@ u32 tpm_nv_write_value(struct udevice *dev, u32 index, const void *data, * * @param dev TPM device * @param index index of the PCR - * @param in_digest 160-bit value representing the event to be + * @param in_digest 160/256-bit value representing the event to be * recorded - * @param out_digest 160-bit PCR value after execution of the + * @param size size of digest in bytes + * @param out_digest 160/256-bit PCR value after execution of the * command + * @param name digest source, used for log output * Return: return code of the operation */ u32 tpm_pcr_extend(struct udevice *dev, u32 index, const void *in_digest, - void *out_digest); + uint size, void *out_digest, const char *name); /** * Issue a TPM_PCRRead command. -- cgit v1.3.1 From 3bb4db4c3883c66ee0bbf152e9ba1d2504fa8c9f Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Tue, 30 Aug 2022 21:05:36 -0600 Subject: tpm: Allow reporting the internal state It is useful to read information about the current TPM state, where supported, e.g. for debugging purposes when verified boot fails. Add support for this to the TPM interface as well as Cr50. Add a simple sandbox test. Signed-off-by: Simon Glass Reviewed-by: Ilias Apalodimas Signed-off-by: Ilias Apalodimas --- cmd/tpm-common.c | 20 ++++++++++++++++++++ cmd/tpm-user-utils.h | 2 ++ cmd/tpm-v2.c | 3 +++ drivers/tpm/tpm-uclass.c | 10 ++++++++++ drivers/tpm/tpm2_tis_sandbox.c | 11 +++++++++++ include/tpm-common.h | 20 ++++++++++++++++++++ test/dm/Makefile | 1 + test/dm/tpm.c | 34 ++++++++++++++++++++++++++++++++++ 8 files changed, 101 insertions(+) create mode 100644 test/dm/tpm.c (limited to 'include') diff --git a/cmd/tpm-common.c b/cmd/tpm-common.c index 47adaffd184..d0c63cadf41 100644 --- a/cmd/tpm-common.c +++ b/cmd/tpm-common.c @@ -333,6 +333,26 @@ int do_tpm_info(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]) return 0; } +int do_tpm_report_state(struct cmd_tbl *cmdtp, int flag, int argc, + char *const argv[]) +{ + struct udevice *dev; + char buf[80]; + int rc; + + rc = get_tpm(&dev); + if (rc) + return rc; + rc = tpm_report_state(dev, buf, sizeof(buf)); + if (rc < 0) { + printf("Couldn't get TPM state (%d)\n", rc); + return CMD_RET_FAILURE; + } + printf("%s\n", buf); + + return 0; +} + int do_tpm_init(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]) { struct udevice *dev; diff --git a/cmd/tpm-user-utils.h b/cmd/tpm-user-utils.h index 358ddff5761..de4a934aab6 100644 --- a/cmd/tpm-user-utils.h +++ b/cmd/tpm-user-utils.h @@ -21,6 +21,8 @@ int do_tpm_device(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]); int do_tpm_init(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]); int do_tpm_info(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]); +int do_tpm_report_state(struct cmd_tbl *cmdtp, int flag, int argc, + char *const argv[]); int do_tpm(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]); #endif /* __TPM_USER_UTILS_H */ diff --git a/cmd/tpm-v2.c b/cmd/tpm-v2.c index 4ea5f9f094f..d93b83ada93 100644 --- a/cmd/tpm-v2.c +++ b/cmd/tpm-v2.c @@ -359,6 +359,7 @@ static int do_tpm_pcr_setauthvalue(struct cmd_tbl *cmdtp, int flag, static struct cmd_tbl tpm2_commands[] = { U_BOOT_CMD_MKENT(device, 0, 1, do_tpm_device, "", ""), U_BOOT_CMD_MKENT(info, 0, 1, do_tpm_info, "", ""), + U_BOOT_CMD_MKENT(state, 0, 1, do_tpm_report_state, "", ""), U_BOOT_CMD_MKENT(init, 0, 1, do_tpm_init, "", ""), U_BOOT_CMD_MKENT(startup, 0, 1, do_tpm2_startup, "", ""), U_BOOT_CMD_MKENT(self_test, 0, 1, do_tpm2_self_test, "", ""), @@ -389,6 +390,8 @@ U_BOOT_CMD(tpm2, CONFIG_SYS_MAXARGS, 1, do_tpm, "Issue a TPMv2.x command", " Show all devices or set the specified device\n" "info\n" " Show information about the TPM.\n" +"state\n" +" Show internal state from the TPM (if available)\n" "init\n" " Initialize the software stack. Always the first command to issue.\n" "startup \n" diff --git a/drivers/tpm/tpm-uclass.c b/drivers/tpm/tpm-uclass.c index 0eb35f50c4e..5ff0cd3958c 100644 --- a/drivers/tpm/tpm-uclass.c +++ b/drivers/tpm/tpm-uclass.c @@ -49,6 +49,16 @@ int tpm_get_desc(struct udevice *dev, char *buf, int size) return ops->get_desc(dev, buf, size); } +int tpm_report_state(struct udevice *dev, char *buf, int size) +{ + struct tpm_ops *ops = tpm_get_ops(dev); + + if (!ops->report_state) + return -ENOSYS; + + return ops->report_state(dev, buf, size); +} + /* Returns max number of milliseconds to wait */ static ulong tpm_tis_i2c_calc_ordinal_duration(struct tpm_chip_priv *priv, u32 ordinal) diff --git a/drivers/tpm/tpm2_tis_sandbox.c b/drivers/tpm/tpm2_tis_sandbox.c index c26f5d35abf..dd94bdc31fb 100644 --- a/drivers/tpm/tpm2_tis_sandbox.c +++ b/drivers/tpm/tpm2_tis_sandbox.c @@ -795,6 +795,16 @@ static int sandbox_tpm2_get_desc(struct udevice *dev, char *buf, int size) return snprintf(buf, size, "Sandbox TPM2.x"); } +static int sandbox_tpm2_report_state(struct udevice *dev, char *buf, int size) +{ + struct sandbox_tpm2 *priv = dev_get_priv(dev); + + if (size < 40) + return -ENOSPC; + + return snprintf(buf, size, "init_done=%d", priv->init_done); +} + static int sandbox_tpm2_open(struct udevice *dev) { struct sandbox_tpm2 *tpm = dev_get_priv(dev); @@ -834,6 +844,7 @@ static const struct tpm_ops sandbox_tpm2_ops = { .open = sandbox_tpm2_open, .close = sandbox_tpm2_close, .get_desc = sandbox_tpm2_get_desc, + .report_state = sandbox_tpm2_report_state, .xfer = sandbox_tpm2_xfer, }; diff --git a/include/tpm-common.h b/include/tpm-common.h index a28629e7013..b2c5404430f 100644 --- a/include/tpm-common.h +++ b/include/tpm-common.h @@ -119,6 +119,16 @@ struct tpm_ops { */ int (*get_desc)(struct udevice *dev, char *buf, int size); + /** + * report_state() - Collect information about the current TPM state + * + * @dev: Device to check + * @buf: Buffer to put the string + * @size: Maximum size of buffer + * Return: return code of the operation (0 = success) + */ + int (*report_state)(struct udevice *dev, char *buf, int size); + /** * send() - send data to the TPM * @@ -234,6 +244,16 @@ u32 tpm_clear_and_reenable(struct udevice *dev); */ int tpm_get_desc(struct udevice *dev, char *buf, int size); +/** + * tpm_report_state() - Collect information about the current TPM state + * + * @dev: Device to check + * @buf: Buffer to put the string + * @size: Maximum size of buffer + * Return: return code of the operation (0 = success) + */ +int tpm_report_state(struct udevice *dev, char *buf, int size); + /** * tpm_xfer() - send data to the TPM and get response * diff --git a/test/dm/Makefile b/test/dm/Makefile index 52fe178a828..7543df8823c 100644 --- a/test/dm/Makefile +++ b/test/dm/Makefile @@ -107,6 +107,7 @@ obj-$(CONFIG_SYSINFO_GPIO) += sysinfo-gpio.o obj-$(CONFIG_UT_DM) += tag.o obj-$(CONFIG_TEE) += tee.o obj-$(CONFIG_TIMER) += timer.o +obj-$(CONFIG_TPM_V2) += tpm.o obj-$(CONFIG_DM_USB) += usb.o obj-$(CONFIG_DM_VIDEO) += video.o ifeq ($(CONFIG_VIRTIO_SANDBOX),y) diff --git a/test/dm/tpm.c b/test/dm/tpm.c new file mode 100644 index 00000000000..0b46f799591 --- /dev/null +++ b/test/dm/tpm.c @@ -0,0 +1,34 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2022 Google LLC + * Written by Simon Glass + */ + +#include +#include +#include +#include +#include +#include + +/* Basic test of the TPM uclass */ +static int dm_test_tpm(struct unit_test_state *uts) +{ + struct udevice *dev; + char buf[50]; + + /* check probe success */ + ut_assertok(uclass_first_device_err(UCLASS_TPM, &dev)); + ut_assert(tpm_is_v2(dev)); + + ut_assert(tpm_report_state(dev, buf, sizeof(buf))); + ut_asserteq_str("init_done=0", buf); + + ut_assertok(tpm_init(dev)); + + ut_assert(tpm_report_state(dev, buf, sizeof(buf))); + ut_asserteq_str("init_done=1", buf); + + return 0; +} +DM_TEST(dm_test_tpm, UT_TESTF_SCAN_FDT); -- cgit v1.3.1 From 4c57ec76b7254cf1743748b70239bddf6100237a Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Tue, 30 Aug 2022 21:05:37 -0600 Subject: tpm: Implement state command for Cr50 Add a vendor-specific TPM2 command for this and implement it for Cr50. Note: This is not part of the TPM spec, but is a Cr50 extension. Signed-off-by: Simon Glass Reviewed-by: Ilias Apalodimas Signed-off-by: Ilias Apalodimas --- drivers/tpm/cr50_i2c.c | 163 +++++++++++++++++++++++++++++++++++++++++++++++++ include/tpm-v2.h | 13 ++++ lib/tpm-v2.c | 25 ++++++++ 3 files changed, 201 insertions(+) (limited to 'include') diff --git a/drivers/tpm/cr50_i2c.c b/drivers/tpm/cr50_i2c.c index f8c30878947..acf4c7859a9 100644 --- a/drivers/tpm/cr50_i2c.c +++ b/drivers/tpm/cr50_i2c.c @@ -13,11 +13,13 @@ #include #include #include +#include #include #include #include #include #include +#include #include #include @@ -37,6 +39,50 @@ enum { CR50_MAX_BUF_SIZE = 63, }; +/* + * Operations specific to the Cr50 TPM used on Chromium OS and Android devices + * + * FIXME: below is not enough to differentiate between vendors commands + * of numerous devices. However, the current tpm2 APIs aren't very amenable + * to extending generically because the marshaling code is assuming all + * knowledge of all commands. + */ +#define TPM2_CC_VENDOR_BIT_MASK 0x20000000 + +#define TPM2_CR50_VENDOR_COMMAND (TPM2_CC_VENDOR_BIT_MASK | 0) +#define TPM2_CR50_SUB_CMD_IMMEDIATE_RESET 19 +#define TPM2_CR50_SUB_CMD_NVMEM_ENABLE_COMMITS 21 +#define TPM2_CR50_SUB_CMD_REPORT_TPM_STATE 23 +#define TPM2_CR50_SUB_CMD_TURN_UPDATE_ON 24 +#define TPM2_CR50_SUB_CMD_GET_REC_BTN 29 +#define TPM2_CR50_SUB_CMD_TPM_MODE 40 +#define TPM2_CR50_SUB_CMD_GET_BOOT_MODE 52 +#define TPM2_CR50_SUB_CMD_RESET_EC 53 + +/* Cr50 vendor-specific error codes. */ +#define VENDOR_RC_ERR 0x00000500 +enum cr50_vendor_rc { + VENDOR_RC_INTERNAL_ERROR = (VENDOR_RC_ERR | 6), + VENDOR_RC_NO_SUCH_SUBCOMMAND = (VENDOR_RC_ERR | 8), + VENDOR_RC_NO_SUCH_COMMAND = (VENDOR_RC_ERR | 127), +}; + +enum cr50_tpm_mode { + /* + * Default state: TPM is enabled, and may be set to either + * TPM_MODE_ENABLED or TPM_MODE_DISABLED. + */ + TPM_MODE_ENABLED_TENTATIVE = 0, + + /* TPM is enabled, and mode may not be changed. */ + TPM_MODE_ENABLED = 1, + + /* TPM is disabled, and mode may not be changed. */ + TPM_MODE_DISABLED = 2, + + TPM_MODE_INVALID, +}; + /** * struct cr50_priv - Private driver data * @@ -54,6 +100,41 @@ struct cr50_priv { bool use_irq; }; +/* + * The below structure represents the body of the response to the 'report tpm + * state' vendor command. + * + * It is transferred over the wire, so it needs to be serialized/deserialized, + * and it is likely to change, so its contents must be versioned. + */ +#define TPM_STATE_VERSION 1 +struct tpm_vendor_state { + u32 version; + /* + * The following three fields are set by the TPM in case of an assert. + * There is no other processing than setting the source code line + * number, error code and the first 4 characters of the function name. + * + * We don't expect this happening, but it is included in the report + * just in case. + */ + u32 fail_line; /* s_failLIne */ + u32 fail_code; /* s_failCode */ + char func_name[4]; /* s_failFunction, limited to 4 chars */ + + /* + * The following two fields are the current time filtered value of the + * 'failed tries' TPM counter, and the maximum allowed value of the + * counter. + * + * failed_tries == max_tries is the definition of the TPM lockout + * condition. + */ + u32 failed_tries; /* gp.failedTries */ + u32 max_tries; /* gp.maxTries */ + /* The below fields are present in version 2 and above */ +}; + /* Wait for interrupt to indicate TPM is ready */ static int cr50_i2c_wait_tpm_ready(struct udevice *dev) { @@ -573,6 +654,87 @@ static int cr50_i2c_get_desc(struct udevice *dev, char *buf, int size) return len; } +static int stringify_state(char *buf, int len, char *str, size_t max_size) +{ + struct tpm_vendor_state state; + size_t text_size = 0; + + state.version = get_unaligned_be32(buf + + offsetof(struct tpm_vendor_state, version)); + state.fail_line = get_unaligned_be32(buf + + offsetof(struct tpm_vendor_state, fail_line)); + state.fail_code = get_unaligned_be32(buf + + offsetof(struct tpm_vendor_state, fail_code)); + memcpy(state.func_name, + buf + offsetof(struct tpm_vendor_state, func_name), + sizeof(state.func_name)); + state.failed_tries = get_unaligned_be32(buf + + offsetof(struct tpm_vendor_state, failed_tries)); + state.max_tries = get_unaligned_be32(buf + + offsetof(struct tpm_vendor_state, max_tries)); + + text_size += snprintf(str + text_size, max_size - text_size, + "v=%d", state.version); + if (text_size >= max_size) + return -ENOSPC; + + if (state.version > TPM_STATE_VERSION) + text_size += snprintf(str + text_size, + max_size - text_size, + " not fully supported\n"); + if (text_size >= max_size) + return -ENOSPC; + + if (state.version == 0) + return -EINVAL; /* This should never happen */ + + text_size += snprintf(str + text_size, + max_size - text_size, + " failed_tries=%d max_tries=%d\n", + state.failed_tries, state.max_tries); + if (text_size >= max_size) + return -ENOSPC; + + if (state.fail_line) { + /* make sure function name is zero terminated. */ + char func_name[sizeof(state.func_name) + 1]; + + memcpy(func_name, state.func_name, sizeof(state.func_name)); + func_name[sizeof(state.func_name)] = '\0'; + + text_size += snprintf(str + text_size, + max_size - text_size, + "tpm failed: f %s line %d code %d", + func_name, + state.fail_line, + state.fail_code); + if (text_size >= max_size) + return -ENOSPC; + } + + return 0; +} + +static int cr50_i2c_report_state(struct udevice *dev, char *str, int str_max) +{ + char buf[50]; + size_t buf_size = sizeof(buf); + int ret; + + ret = tpm2_report_state(dev, TPM2_CR50_VENDOR_COMMAND, + TPM2_CR50_SUB_CMD_REPORT_TPM_STATE, + buf, &buf_size); + if (ret) + return ret; + + /* TPM responded as expected */ + ret = stringify_state(buf, buf_size, str, str_max); + if (ret) + return ret; + + return 0; +} + static int cr50_i2c_open(struct udevice *dev) { char buf[80]; @@ -730,6 +892,7 @@ struct acpi_ops cr50_acpi_ops = { static const struct tpm_ops cr50_i2c_ops = { .open = cr50_i2c_open, .get_desc = cr50_i2c_get_desc, + .report_state = cr50_i2c_report_state, .send = cr50_i2c_send, .recv = cr50_i2c_recv, .cleanup = cr50_i2c_cleanup, diff --git a/include/tpm-v2.h b/include/tpm-v2.h index e79c90b9395..36c6ac0be6e 100644 --- a/include/tpm-v2.h +++ b/include/tpm-v2.h @@ -658,4 +658,17 @@ u32 tpm2_disable_platform_hierarchy(struct udevice *dev); u32 tpm2_submit_command(struct udevice *dev, const u8 *sendbuf, u8 *recvbuf, size_t *recv_size); +/** + * tpm_cr50_report_state() - Report the Cr50 internal state + * + * @dev: TPM device + * @vendor_cmd: Vendor command number to send + * @vendor_subcmd: Vendor sub-command number to send + * @recvbuf: Buffer to save the response to + * @recv_size: Pointer to the size of the response buffer + * Return: result of the operation + */ +u32 tpm2_report_state(struct udevice *dev, uint vendor_cmd, uint vendor_subcmd, + u8 *recvbuf, size_t *recv_size); + #endif /* __TPM_V2_H */ diff --git a/lib/tpm-v2.c b/lib/tpm-v2.c index 3e240bb4c67..edee9854a7c 100644 --- a/lib/tpm-v2.c +++ b/lib/tpm-v2.c @@ -679,3 +679,28 @@ u32 tpm2_submit_command(struct udevice *dev, const u8 *sendbuf, { return tpm_sendrecv_command(dev, sendbuf, recvbuf, recv_size); } + +u32 tpm2_report_state(struct udevice *dev, uint vendor_cmd, uint vendor_subcmd, + u8 *recvbuf, size_t *recv_size) +{ + u8 command_v2[COMMAND_BUFFER_SIZE] = { + /* header 10 bytes */ + tpm_u16(TPM2_ST_NO_SESSIONS), /* TAG */ + tpm_u32(10 + 2), /* Length */ + tpm_u32(vendor_cmd), /* Command code */ + + tpm_u16(vendor_subcmd), + }; + int ret; + + ret = tpm_sendrecv_command(dev, command_v2, recvbuf, recv_size); + log_debug("ret=%s, %x\n", dev->name, ret); + if (ret) + return ret; + if (*recv_size < 12) + return -ENODATA; + *recv_size -= 12; + memcpy(recvbuf, recvbuf + 12, *recv_size); + + return 0; +} -- cgit v1.3.1 From 5208ed187cb6314dc64657802e8e5bb5a5e3a7fb Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Tue, 30 Aug 2022 21:05:38 -0600 Subject: tpm: Allow committing non-volatile data Add an option to tell the TPM to commit non-volatile data immediately it is changed, rather than waiting until later. This is needed in some situations, since if the device reboots it may not write the data. Add definitions for the rest of the Cr50 commands while we are here. Signed-off-by: Simon Glass Reviewed-by: Ilias Apalodimas Signed-off-by: Ilias Apalodimas --- include/tpm-v2.h | 17 +++++++++++++++++ lib/tpm-v2.c | 21 +++++++++++++++++++++ 2 files changed, 38 insertions(+) (limited to 'include') diff --git a/include/tpm-v2.h b/include/tpm-v2.h index 36c6ac0be6e..737e57551d7 100644 --- a/include/tpm-v2.h +++ b/include/tpm-v2.h @@ -671,4 +671,21 @@ u32 tpm2_submit_command(struct udevice *dev, const u8 *sendbuf, u32 tpm2_report_state(struct udevice *dev, uint vendor_cmd, uint vendor_subcmd, u8 *recvbuf, size_t *recv_size); +/** + * tpm2_enable_nvcommits() - Tell TPM to commit NV data immediately + * + * For Chromium OS verified boot, we may reboot or reset at different times, + * possibly leaving non-volatile data unwritten by the TPM. + * + * This vendor command is used to indicate that non-volatile data should be + * written to its store immediately. + * + * @dev TPM device + * @vendor_cmd: Vendor command number to send + * @vendor_subcmd: Vendor sub-command number to send + * Return: result of the operation + */ +u32 tpm2_enable_nvcommits(struct udevice *dev, uint vendor_cmd, + uint vendor_subcmd); + #endif /* __TPM_V2_H */ diff --git a/lib/tpm-v2.c b/lib/tpm-v2.c index edee9854a7c..697b982e079 100644 --- a/lib/tpm-v2.c +++ b/lib/tpm-v2.c @@ -704,3 +704,24 @@ u32 tpm2_report_state(struct udevice *dev, uint vendor_cmd, uint vendor_subcmd, return 0; } + +u32 tpm2_enable_nvcommits(struct udevice *dev, uint vendor_cmd, + uint vendor_subcmd) +{ + u8 command_v2[COMMAND_BUFFER_SIZE] = { + /* header 10 bytes */ + tpm_u16(TPM2_ST_NO_SESSIONS), /* TAG */ + tpm_u32(10 + 2), /* Length */ + tpm_u32(vendor_cmd), /* Command code */ + + tpm_u16(vendor_subcmd), + }; + int ret; + + ret = tpm_sendrecv_command(dev, command_v2, NULL, NULL); + log_debug("ret=%s, %x\n", dev->name, ret); + if (ret) + return ret; + + return 0; +} -- cgit v1.3.1