// SPDX-License-Identifier: GPL-2.0+
/*
 * Defines APIs that allow an OS to interact with UEFI firmware to query
 * information about the device.
 * https://trustedcomputinggroup.org/resource/tcg-efi-protocol-specification/
 *
 * Copyright (c) 2020, Linaro Limited
 */

#define LOG_CATEGORY LOGC_EFI
#include <common.h>
#include <dm.h>
#include <efi_loader.h>
#include <efi_variable.h>
#include <efi_tcg2.h>
#include <log.h>
#include <malloc.h>
#include <smbios.h>
#include <version_string.h>
#include <tpm-v2.h>
#include <tpm_api.h>
#include <u-boot/hash-checksum.h>
#include <u-boot/sha1.h>
#include <u-boot/sha256.h>
#include <u-boot/sha512.h>
#include <linux/unaligned/be_byteshift.h>
#include <linux/unaligned/le_byteshift.h>
#include <linux/unaligned/generic.h>
#include <hexdump.h>

/**
 * struct event_log_buffer - internal eventlog management structure
 *
 * @buffer:             eventlog buffer
 * @final_buffer:       finalevent config table buffer
 * @pos:                current position of 'buffer'
 * @final_pos:          current position of 'final_buffer'
 * @get_event_called:   true if GetEventLog has been invoked at least once
 * @ebs_called:         true if ExitBootServices has been invoked
 * @truncated:          true if the 'buffer' is truncated
 */
struct event_log_buffer {
        void *buffer;
        void *final_buffer;
        size_t pos; /* eventlog position */
        size_t final_pos; /* final events config table position */
        size_t last_event_size;
        bool get_event_called;
        bool ebs_called;
        bool truncated;
};

static struct event_log_buffer event_log;
static bool tcg2_efi_app_invoked;
/*
 * When requesting TPM2_CAP_TPM_PROPERTIES the value is on a standard offset.
 * Since the current tpm2_get_capability() response buffers starts at
 * 'union tpmu_capabilities data' of 'struct tpms_capability_data', calculate
 * the response size and offset once for all consumers
 */
#define TPM2_RESPONSE_BUFFER_SIZE (sizeof(struct tpms_capability_data) - \
                                   offsetof(struct tpms_capability_data, data))
#define properties_offset (offsetof(struct tpml_tagged_tpm_property, tpm_property) + \
                           offsetof(struct tpms_tagged_property, value))

static const efi_guid_t efi_guid_tcg2_protocol = EFI_TCG2_PROTOCOL_GUID;
static const efi_guid_t efi_guid_final_events = EFI_TCG2_FINAL_EVENTS_TABLE_GUID;

struct digest_info {
        u16 hash_alg;
        u32 hash_mask;
        u16 hash_len;
};

static const struct digest_info hash_algo_list[] = {
        {
                TPM2_ALG_SHA1,
                EFI_TCG2_BOOT_HASH_ALG_SHA1,
                TPM2_SHA1_DIGEST_SIZE,
        },
        {
                TPM2_ALG_SHA256,
                EFI_TCG2_BOOT_HASH_ALG_SHA256,
                TPM2_SHA256_DIGEST_SIZE,
        },
        {
                TPM2_ALG_SHA384,
                EFI_TCG2_BOOT_HASH_ALG_SHA384,
                TPM2_SHA384_DIGEST_SIZE,
        },
        {
                TPM2_ALG_SHA512,
                EFI_TCG2_BOOT_HASH_ALG_SHA512,
                TPM2_SHA512_DIGEST_SIZE,
        },
};

struct variable_info {
        const u16       *name;
        bool            accept_empty;
        u32             pcr_index;
};

static struct variable_info secure_variables[] = {
        {u"SecureBoot",         true,   7},
        {u"PK",                 true,   7},
        {u"KEK",                true,   7},
        {u"db",                 true,   7},
        {u"dbx",                true,   7},
        {u"dbt",                false,  7},
        {u"dbr",                false,  7},
        {u"DeployedMode",       false,  1},
        {u"AuditMode",          false,  1},
};

#define MAX_HASH_COUNT ARRAY_SIZE(hash_algo_list)

/**
 * alg_to_mask - Get a TCG hash mask for algorithms
 *
 * @hash_alg: TCG defined algorithm
 *
 * @Return: TCG hashing algorithm bitmaps, 0 if the algorithm is not supported
 */
static u32 alg_to_mask(u16 hash_alg)
{
        size_t i;

        for (i = 0; i < MAX_HASH_COUNT; i++) {
                if (hash_algo_list[i].hash_alg == hash_alg)
                        return hash_algo_list[i].hash_mask;
        }

        return 0;
}

/**
 * alg_to_len - Get a TCG hash len for algorithms
 *
 * @hash_alg: TCG defined algorithm
 *
 * @Return: len of chosen algorithm, 0 if the algorithm is not supported
 */
static u16 alg_to_len(u16 hash_alg)
{
        size_t i;

        for (i = 0; i < MAX_HASH_COUNT; i++) {
                if (hash_algo_list[i].hash_alg == hash_alg)
                        return hash_algo_list[i].hash_len;
        }

        return 0;
}

static bool is_tcg2_protocol_installed(void)
{
        struct efi_handler *handler;
        efi_status_t ret;

        ret = efi_search_protocol(efi_root, &efi_guid_tcg2_protocol, &handler);
        return ret == EFI_SUCCESS;
}

static u32 tcg_event_final_size(struct tpml_digest_values *digest_list)
{
        u32 len;
        size_t i;

        len = offsetof(struct tcg_pcr_event2, digests);
        len += offsetof(struct tpml_digest_values, digests);
        for (i = 0; i < digest_list->count; i++) {
                u16 hash_alg = digest_list->digests[i].hash_alg;

                len += offsetof(struct tpmt_ha, digest);
                len += alg_to_len(hash_alg);
        }
        len += sizeof(u32); /* tcg_pcr_event2 event_size*/

        return len;
}

/* tcg2_pcr_extend - Extend PCRs for a TPM2 device for a given tpml_digest_values
 *
 * @dev:                device
 * @digest_list:        list of digest algorithms to extend
 *
 * @Return: status code
 */
static efi_status_t tcg2_pcr_extend(struct udevice *dev, u32 pcr_index,
                                    struct tpml_digest_values *digest_list)
{
        u32 rc;
        size_t i;

        for (i = 0; i < digest_list->count; i++) {
                u32 alg = digest_list->digests[i].hash_alg;

                rc = tpm2_pcr_extend(dev, pcr_index, alg,
                                     (u8 *)&digest_list->digests[i].digest,
                                     alg_to_len(alg));
                if (rc) {
                        EFI_PRINT("Failed to extend PCR\n");
                        return EFI_DEVICE_ERROR;
                }
        }

        return EFI_SUCCESS;
}

/* tcg2_pcr_read - Read PCRs for a TPM2 device for a given tpml_digest_values
 *
 * @dev:                device
 * @pcr_index:          PCR index
 * @digest_list:        list of digest algorithms to extend
 *
 * @Return: status code
 */
static efi_status_t tcg2_pcr_read(struct udevice *dev, u32 pcr_index,
                                  struct tpml_digest_values *digest_list)
{
        struct tpm_chip_priv *priv;
        unsigned int updates, pcr_select_min;
        u32 rc;
        size_t i;

        priv = dev_get_uclass_priv(dev);
        if (!priv)
                return EFI_DEVICE_ERROR;

        pcr_select_min = priv->pcr_select_min;

        for (i = 0; i < digest_list->count; i++) {
                u16 hash_alg = digest_list->digests[i].hash_alg;
                u8 *digest = (u8 *)&digest_list->digests[i].digest;

                rc = tpm2_pcr_read(dev, pcr_index, pcr_select_min,
                                   hash_alg, digest, alg_to_len(hash_alg),
                                   &updates);
                if (rc) {
                        EFI_PRINT("Failed to read PCR\n");
                        return EFI_DEVICE_ERROR;
                }
        }

        return EFI_SUCCESS;
}

/* put_event - Append an agile event to an eventlog
 *
 * @pcr_index:          PCR index
 * @event_type:         type of event added
 * @digest_list:        list of digest algorithms to add
 * @size:               size of event
 * @event:              event to add
 * @log:                log buffer to append the event
 *
 */
static void put_event(u32 pcr_index, u32 event_type,
                      struct tpml_digest_values *digest_list, u32 size,
                      u8 event[], void *log)
{
        size_t pos;
        size_t i;
        u32 event_size;

        /*
         * size refers to the length of event[] only, we need to check against
         * the final tcg_pcr_event2 size
         */
        event_size = size + tcg_event_final_size(digest_list);

        put_unaligned_le32(pcr_index, log);
        pos = offsetof(struct tcg_pcr_event2, event_type);
        put_unaligned_le32(event_type, (void *)((uintptr_t)log + pos));
        pos = offsetof(struct tcg_pcr_event2, digests); /* count */
        put_unaligned_le32(digest_list->count, (void *)((uintptr_t)log + pos));

        pos += offsetof(struct tpml_digest_values, digests);
        for (i = 0; i < digest_list->count; i++) {
                u16 hash_alg = digest_list->digests[i].hash_alg;
                u8 *digest = (u8 *)&digest_list->digests[i].digest;

                put_unaligned_le16(hash_alg, (void *)((uintptr_t)log + pos));
                pos += offsetof(struct tpmt_ha, digest);
                memcpy((void *)((uintptr_t)log + pos), digest, alg_to_len(hash_alg));
                pos += alg_to_len(hash_alg);
        }

        put_unaligned_le32(size, (void *)((uintptr_t)log + pos));
        pos += sizeof(u32); /* tcg_pcr_event2 event_size*/
        memcpy((void *)((uintptr_t)log + pos), event, size);
        pos += size;

        /*
         * make sure the calculated buffer is what we checked against
         * This check should never fail.  It checks the code above is
         * calculating the right length for the event we are adding
         */
        if (pos != event_size)
                log_err("Appending to the EventLog failed\n");
}

/* tcg2_agile_log_append - Append an agile event to an eventlog
 *
 * @pcr_index:          PCR index
 * @event_type:         type of event added
 * @digest_list:        list of digest algorithms to add
 * @size:               size of event
 * @event:              event to add
 * @log:                log buffer to append the event
 *
 * @Return: status code
 */
static efi_status_t tcg2_agile_log_append(u32 pcr_index, u32 event_type,
                                          struct tpml_digest_values *digest_list,
                                          u32 size, u8 event[])
{
        void *log = (void *)((uintptr_t)event_log.buffer + event_log.pos);
        u32 event_size = size + tcg_event_final_size(digest_list);
        struct efi_tcg2_final_events_table *final_event;
        efi_status_t ret = EFI_SUCCESS;

        /* if ExitBootServices hasn't been called update the normal log */
        if (!event_log.ebs_called) {
                if (event_log.truncated ||
                    event_log.pos + event_size > TPM2_EVENT_LOG_SIZE) {
                        event_log.truncated = true;
                        return EFI_VOLUME_FULL;
                }
                put_event(pcr_index, event_type, digest_list, size, event, log);
                event_log.pos += event_size;
                event_log.last_event_size = event_size;
        }

        if (!event_log.get_event_called)
                return ret;

        /* if GetEventLog has been called update FinalEventLog as well */
        if (event_log.final_pos + event_size > TPM2_EVENT_LOG_SIZE)
                return EFI_VOLUME_FULL;

        log = (void *)((uintptr_t)event_log.final_buffer + event_log.final_pos);
        put_event(pcr_index, event_type, digest_list, size, event, log);

        final_event = event_log.final_buffer;
        final_event->number_of_events++;
        event_log.final_pos += event_size;

        return ret;
}

/**
 * platform_get_tpm_device() - retrieve TPM device
 *
 * This function retrieves the udevice implementing a TPM
 *
 * This function may be overridden if special initialization is needed.
 *
 * @dev:        udevice
 * Return:      status code
 */
__weak efi_status_t platform_get_tpm2_device(struct udevice **dev)
{
        for_each_tpm_device(*dev) {
                /* Only support TPMv2 devices */
                if (tpm_get_version(*dev) == TPM_V2)
                        return EFI_SUCCESS;
        }

        return EFI_NOT_FOUND;
}

/**
 * platform_get_eventlog() - retrieve the eventlog address and size
 *
 * This function retrieves the eventlog address and size if the underlying
 * firmware has done some measurements and passed them.
 *
 * This function may be overridden based on platform specific method of
 * passing the eventlog address and size.
 *
 * @dev:        udevice
 * @addr:       eventlog address
 * @sz:         eventlog size
 * Return:      status code
 */
__weak efi_status_t platform_get_eventlog(struct udevice *dev, u64 *addr,
                                          u32 *sz)
{
        const u64 *basep;
        const u32 *sizep;

        basep = dev_read_prop(dev, "tpm_event_log_addr", NULL);
        if (!basep)
                return EFI_NOT_FOUND;

        *addr = be64_to_cpup((__force __be64 *)basep);

        sizep = dev_read_prop(dev, "tpm_event_log_size", NULL);
        if (!sizep)
                return EFI_NOT_FOUND;

        *sz = be32_to_cpup((__force __be32 *)sizep);
        if (*sz == 0) {
                log_debug("event log empty\n");
                return EFI_NOT_FOUND;
        }

        return EFI_SUCCESS;
}

/**
 * tpm2_get_max_command_size() - get the supported max command size
 *
 * @dev:                TPM device
 * @max_command_size:   output buffer for the size
 *
 * Return: 0 on success, -1 on error
 */
static int tpm2_get_max_command_size(struct udevice *dev, u16 *max_command_size)
{
        u8 response[TPM2_RESPONSE_BUFFER_SIZE];
        u32 ret;

        memset(response, 0, sizeof(response));
        ret = tpm2_get_capability(dev, TPM2_CAP_TPM_PROPERTIES,
                                  TPM2_PT_MAX_COMMAND_SIZE, response, 1);
        if (ret)
                return -1;

        *max_command_size = (uint16_t)get_unaligned_be32(response +
                                                         properties_offset);

        return 0;
}

/**
 * tpm2_get_max_response_size() - get the supported max response size
 *
 * @dev:                TPM device
 * @max_response_size:  output buffer for the size
 *
 * Return: 0 on success, -1 on error
 */
static int tpm2_get_max_response_size(struct udevice *dev,
                                      u16 *max_response_size)
{
        u8 response[TPM2_RESPONSE_BUFFER_SIZE];
        u32 ret;

        memset(response, 0, sizeof(response));
        ret = tpm2_get_capability(dev, TPM2_CAP_TPM_PROPERTIES,
                                  TPM2_PT_MAX_RESPONSE_SIZE, response, 1);
        if (ret)
                return -1;

        *max_response_size = (uint16_t)get_unaligned_be32(response +
                                                          properties_offset);

        return 0;
}

/**
 * tpm2_get_manufacturer_id() - get the manufacturer ID
 *
 * @dev:                TPM device
 * @manufacturer_id:    output buffer for the id
 *
 * Return: 0 on success, -1 on error
 */
static int tpm2_get_manufacturer_id(struct udevice *dev, u32 *manufacturer_id)
{
        u8 response[TPM2_RESPONSE_BUFFER_SIZE];
        u32 ret;

        memset(response, 0, sizeof(response));
        ret = tpm2_get_capability(dev, TPM2_CAP_TPM_PROPERTIES,
                                  TPM2_PT_MANUFACTURER, response, 1);
        if (ret)
                return -1;

        *manufacturer_id = get_unaligned_be32(response + properties_offset);

        return 0;
}

/**
 * tpm2_get_num_pcr() - get the number of PCRs
 *
 * @dev:                TPM device
 * @manufacturer_id:    output buffer for the number
 *
 * Return: 0 on success, -1 on error
 */
static int tpm2_get_num_pcr(struct udevice *dev, u32 *num_pcr)
{
        u8 response[TPM2_RESPONSE_BUFFER_SIZE];
        u32 ret;

        memset(response, 0, sizeof(response));
        ret = tpm2_get_capability(dev, TPM2_CAP_TPM_PROPERTIES,
                                  TPM2_PT_PCR_COUNT, response, 1);
        if (ret)
                return -1;

        *num_pcr = get_unaligned_be32(response + properties_offset);
        if (*num_pcr > TPM2_MAX_PCRS)
                return -1;

        return 0;
}

/**
 * is_active_pcr() - Check if a supported algorithm is active
 *
 * @dev:                TPM device
 * @selection:          struct of PCR information
 *
 * Return: true if PCR is active
 */
static bool is_active_pcr(struct tpms_pcr_selection *selection)
{
        int i;
        /*
         * check the pcr_select. If at least one of the PCRs supports the
         * algorithm add it on the active ones
         */
        for (i = 0; i < selection->size_of_select; i++) {
                if (selection->pcr_select[i])
                        return true;
        }

        return false;
}

/**
 * tpm2_get_pcr_info() - get the supported, active PCRs and number of banks
 *
 * @dev:                TPM device
 * @supported_pcr:      bitmask with the algorithms supported
 * @active_pcr:         bitmask with the active algorithms
 * @pcr_banks:          number of PCR banks
 *
 * Return: 0 on success, -1 on error
 */
static int tpm2_get_pcr_info(struct udevice *dev, u32 *supported_pcr,
                             u32 *active_pcr, u32 *pcr_banks)
{
        u8 response[TPM2_RESPONSE_BUFFER_SIZE];
        struct tpml_pcr_selection pcrs;
        u32 ret, num_pcr;
        size_t i;
        int tpm_ret;

        *supported_pcr = 0;
        *active_pcr = 0;
        *pcr_banks = 0;
        memset(response, 0, sizeof(response));
        ret = tpm2_get_capability(dev, TPM2_CAP_PCRS, 0, response, 1);
        if (ret)
                goto out;

        pcrs.count = get_unaligned_be32(response);
        /*
         * We only support 5 algorithms for now so check against that
         * instead of TPM2_NUM_PCR_BANKS
         */
        if (pcrs.count > MAX_HASH_COUNT || pcrs.count < 1)
                goto out;

        tpm_ret = tpm2_get_num_pcr(dev, &num_pcr);
        if (tpm_ret)
                goto out;

        for (i = 0; i < pcrs.count; i++) {
                /*
                 * Definition of TPMS_PCR_SELECTION Structure
                 * hash: u16
                 * size_of_select: u8
                 * pcr_select: u8 array
                 *
                 * The offsets depend on the number of the device PCRs
                 * so we have to calculate them based on that
                 */
                u32 hash_offset = offsetof(struct tpml_pcr_selection, selection) +
                        i * offsetof(struct tpms_pcr_selection, pcr_select) +
                        i * ((num_pcr + 7) / 8);
                u32 size_select_offset =
                        hash_offset + offsetof(struct tpms_pcr_selection,
                                               size_of_select);
                u32 pcr_select_offset =
                        hash_offset + offsetof(struct tpms_pcr_selection,
                                               pcr_select);

                pcrs.selection[i].hash =
                        get_unaligned_be16(response + hash_offset);
                pcrs.selection[i].size_of_select =
                        __get_unaligned_be(response + size_select_offset);
                if (pcrs.selection[i].size_of_select > TPM2_PCR_SELECT_MAX)
                        goto out;
                /* copy the array of pcr_select */
                memcpy(pcrs.selection[i].pcr_select, response + pcr_select_offset,
                       pcrs.selection[i].size_of_select);
        }

        for (i = 0; i < pcrs.count; i++) {
                u32 hash_mask = alg_to_mask(pcrs.selection[i].hash);

                if (hash_mask) {
                        *supported_pcr |= hash_mask;
                        if (is_active_pcr(&pcrs.selection[i]))
                                *active_pcr |= hash_mask;
                } else {
                        EFI_PRINT("Unknown algorithm %x\n", pcrs.selection[i].hash);
                }
        }

        *pcr_banks = pcrs.count;

        return 0;
out:
        return -1;
}

/**
 * __get_active_pcr_banks() - returns the currently active PCR banks
 *
 * @active_pcr_banks:           pointer for receiving the bitmap of currently
 *                              active PCR banks
 *
 * Return:      status code
 */
static efi_status_t __get_active_pcr_banks(u32 *active_pcr_banks)
{
        struct udevice *dev;
        u32 active = 0, supported = 0, pcr_banks = 0;
        efi_status_t ret;
        int err;

        ret = platform_get_tpm2_device(&dev);
        if (ret != EFI_SUCCESS)
                goto out;

        err = tpm2_get_pcr_info(dev, &supported, &active, &pcr_banks);
        if (err) {
                ret = EFI_DEVICE_ERROR;
                goto out;
        }

        *active_pcr_banks = active;

out:
        return ret;
}

/* tcg2_create_digest - create a list of digests of the supported PCR banks
 *                      for a given memory range
 *
 * @input:              input memory
 * @length:             length of buffer to calculate the digest
 * @digest_list:        list of digests to fill in
 *
 * Return:              status code
 */
static efi_status_t tcg2_create_digest(const u8 *input, u32 length,
                                       struct tpml_digest_values *digest_list)
{
        sha1_context ctx;
        sha256_context ctx_256;
        sha512_context ctx_512;
        u8 final[TPM2_SHA512_DIGEST_SIZE];
        efi_status_t ret;
        u32 active;
        size_t i;

        ret = __get_active_pcr_banks(&active);
        if (ret != EFI_SUCCESS)
                return ret;

        digest_list->count = 0;
        for (i = 0; i < MAX_HASH_COUNT; i++) {
                u16 hash_alg = hash_algo_list[i].hash_alg;

                if (!(active & alg_to_mask(hash_alg)))
                        continue;
                switch (hash_alg) {
                case TPM2_ALG_SHA1:
                        sha1_starts(&ctx);
                        sha1_update(&ctx, input, length);
                        sha1_finish(&ctx, final);
                        break;
                case TPM2_ALG_SHA256:
                        sha256_starts(&ctx_256);
                        sha256_update(&ctx_256, input, length);
                        sha256_finish(&ctx_256, final);
                        break;
                case TPM2_ALG_SHA384:
                        sha384_starts(&ctx_512);
                        sha384_update(&ctx_512, input, length);
                        sha384_finish(&ctx_512, final);
                        break;
                case TPM2_ALG_SHA512:
                        sha512_starts(&ctx_512);
                        sha512_update(&ctx_512, input, length);
                        sha512_finish(&ctx_512, final);
                        break;
                default:
                        EFI_PRINT("Unsupported algorithm %x\n", hash_alg);
                        return EFI_INVALID_PARAMETER;
                }
                digest_list->digests[digest_list->count].hash_alg = hash_alg;
                memcpy(&digest_list->digests[digest_list->count].digest, final,
                       (u32)alg_to_len(hash_alg));
                digest_list->count++;
        }

        return EFI_SUCCESS;
}

/**
 * efi_tcg2_get_capability() - protocol capability information and state information
 *
 * @this:               TCG2 protocol instance
 * @capability:         caller allocated memory with size field to the size of
 *                      the structure allocated

 * Return:      status code
 */
static efi_status_t EFIAPI
efi_tcg2_get_capability(struct efi_tcg2_protocol *this,
                        struct efi_tcg2_boot_service_capability *capability)
{
        struct udevice *dev;
        efi_status_t efi_ret;
        int ret;

        EFI_ENTRY("%p, %p", this, capability);

        if (!this || !capability) {
                efi_ret = EFI_INVALID_PARAMETER;
                goto out;
        }

        if (capability->size < BOOT_SERVICE_CAPABILITY_MIN) {
                capability->size = BOOT_SERVICE_CAPABILITY_MIN;
                efi_ret = EFI_BUFFER_TOO_SMALL;
                goto out;
        }

        if (capability->size < sizeof(*capability)) {
                capability->size = sizeof(*capability);
                efi_ret = EFI_BUFFER_TOO_SMALL;
                goto out;
        }

        capability->structure_version.major = 1;
        capability->structure_version.minor = 1;
        capability->protocol_version.major = 1;
        capability->protocol_version.minor = 1;

        efi_ret = platform_get_tpm2_device(&dev);
        if (efi_ret != EFI_SUCCESS) {
                capability->supported_event_logs = 0;
                capability->hash_algorithm_bitmap = 0;
                capability->tpm_present_flag = false;
                capability->max_command_size = 0;
                capability->max_response_size = 0;
                capability->manufacturer_id = 0;
                capability->number_of_pcr_banks = 0;
                capability->active_pcr_banks = 0;

                efi_ret = EFI_SUCCESS;
                goto out;
        }

        /* We only allow a TPMv2 device to register the EFI protocol */
        capability->supported_event_logs = TCG2_EVENT_LOG_FORMAT_TCG_2;

        capability->tpm_present_flag = true;

        /* Supported and active PCRs */
        capability->hash_algorithm_bitmap = 0;
        capability->active_pcr_banks = 0;
        ret = tpm2_get_pcr_info(dev, &capability->hash_algorithm_bitmap,
                                &capability->active_pcr_banks,
                                &capability->number_of_pcr_banks);
        if (ret) {
                efi_ret = EFI_DEVICE_ERROR;
                goto out;
        }

        /* Max command size */
        ret = tpm2_get_max_command_size(dev, &capability->max_command_size);
        if (ret) {
                efi_ret = EFI_DEVICE_ERROR;
                goto out;
        }

        /* Max response size */
        ret = tpm2_get_max_response_size(dev, &capability->max_response_size);
        if (ret) {
                efi_ret = EFI_DEVICE_ERROR;
                goto out;
        }

        /* Manufacturer ID */
        ret = tpm2_get_manufacturer_id(dev, &capability->manufacturer_id);
        if (ret) {
                efi_ret = EFI_DEVICE_ERROR;
                goto out;
        }

        return EFI_EXIT(EFI_SUCCESS);
out:
        return EFI_EXIT(efi_ret);
}

/**
 * efi_tcg2_get_eventlog() -    retrieve the the address of an event log and its
 *                              last entry
 *
 * @this:                       TCG2 protocol instance
 * @log_format:                 type of event log format
 * @event_log_location:         pointer to the memory address of the event log
 * @event_log_last_entry:       pointer to the address of the start of the last
 *                              entry in the event log in memory, if log contains
 *                              more than 1 entry
 * @event_log_truncated:        set to true, if the Event Log is missing at i
 *                              least one entry
 *
 * Return:      status code
 */
static efi_status_t EFIAPI
efi_tcg2_get_eventlog(struct efi_tcg2_protocol *this,
                      efi_tcg_event_log_format log_format,
                      u64 *event_log_location, u64 *event_log_last_entry,
                      bool *event_log_truncated)
{
        efi_status_t ret = EFI_SUCCESS;
        struct udevice *dev;

        EFI_ENTRY("%p, %u, %p, %p,  %p", this, log_format, event_log_location,
                  event_log_last_entry, event_log_truncated);

        if (!this || !event_log_location || !event_log_last_entry ||
            !event_log_truncated) {
                ret = EFI_INVALID_PARAMETER;
                goto out;
        }

        /* Only support TPMV2 */
        if (log_format != TCG2_EVENT_LOG_FORMAT_TCG_2) {
                ret = EFI_INVALID_PARAMETER;
                goto out;
        }

        ret = platform_get_tpm2_device(&dev);
        if (ret != EFI_SUCCESS) {
                event_log_location = NULL;
                event_log_last_entry = NULL;
                *event_log_truncated = false;
                ret = EFI_SUCCESS;
                goto out;
        }
        *event_log_location = (uintptr_t)event_log.buffer;
        *event_log_last_entry = (uintptr_t)(event_log.buffer + event_log.pos -
                                            event_log.last_event_size);
        *event_log_truncated = event_log.truncated;
        event_log.get_event_called = true;

out:
        return EFI_EXIT(ret);
}

/**
 * tcg2_hash_pe_image() - calculate PE/COFF image hash
 *
 * @efi:                pointer to the EFI binary
 * @efi_size:           size of @efi binary
 * @digest_list:        list of digest algorithms to extend
 *
 * Return:      status code
 */
static efi_status_t tcg2_hash_pe_image(void *efi, u64 efi_size,
                                       struct tpml_digest_values *digest_list)
{
        WIN_CERTIFICATE *wincerts = NULL;
        size_t wincerts_len;
        struct efi_image_regions *regs = NULL;
        void *new_efi = NULL;
        u8 hash[TPM2_SHA512_DIGEST_SIZE];
        efi_status_t ret;
        u32 active;
        int i;

        new_efi = efi_prepare_aligned_image(efi, &efi_size);
        if (!new_efi)
                return EFI_OUT_OF_RESOURCES;

        if (!efi_image_parse(new_efi, efi_size, &regs, &wincerts,
                             &wincerts_len)) {
                log_err("Parsing PE executable image failed\n");
                ret = EFI_UNSUPPORTED;
                goto out;
        }

        ret = __get_active_pcr_banks(&active);
        if (ret != EFI_SUCCESS) {
                goto out;
        }

        digest_list->count = 0;
        for (i = 0; i < MAX_HASH_COUNT; i++) {
                u16 hash_alg = hash_algo_list[i].hash_alg;

                if (!(active & alg_to_mask(hash_alg)))
                        continue;
                switch (hash_alg) {
                case TPM2_ALG_SHA1:
                        hash_calculate("sha1", regs->reg, regs->num, hash);
                        break;
                case TPM2_ALG_SHA256:
                        hash_calculate("sha256", regs->reg, regs->num, hash);
                        break;
                case TPM2_ALG_SHA384:
                        hash_calculate("sha384", regs->reg, regs->num, hash);
                        break;
                case TPM2_ALG_SHA512:
                        hash_calculate("sha512", regs->reg, regs->num, hash);
                        break;
                default:
                        EFI_PRINT("Unsupported algorithm %x\n", hash_alg);
                        return EFI_INVALID_PARAMETER;
                }
                digest_list->digests[digest_list->count].hash_alg = hash_alg;
                memcpy(&digest_list->digests[digest_list->count].digest, hash,
                       (u32)alg_to_len(hash_alg));
                digest_list->count++;
        }

out:
        if (new_efi != efi)
                free(new_efi);
        free(regs);

        return ret;
}

/**
 * tcg2_measure_pe_image() - measure PE/COFF image
 *
 * @efi:                pointer to the EFI binary
 * @efi_size:           size of @efi binary
 * @handle:             loaded image handle
 * @loaded_image:       loaded image protocol
 *
 * Return:      status code
 */
efi_status_t tcg2_measure_pe_image(void *efi, u64 efi_size,
                                   struct efi_loaded_image_obj *handle,
                                   struct efi_loaded_image *loaded_image)
{
        struct tpml_digest_values digest_list;
        efi_status_t ret;
        struct udevice *dev;
        u32 pcr_index, event_type, event_size;
        struct uefi_image_load_event *image_load_event;
        struct efi_device_path *device_path;
        u32 device_path_length;
        IMAGE_DOS_HEADER *dos;
        IMAGE_NT_HEADERS32 *nt;
        struct efi_handler *handler;

        if (!is_tcg2_protocol_installed())
                return EFI_SUCCESS;

        ret = platform_get_tpm2_device(&dev);
        if (ret != EFI_SUCCESS)
                return EFI_SECURITY_VIOLATION;

        switch (handle->image_type) {
        case IMAGE_SUBSYSTEM_EFI_APPLICATION:
                pcr_index = 4;
                event_type = EV_EFI_BOOT_SERVICES_APPLICATION;
                break;
        case IMAGE_SUBSYSTEM_EFI_BOOT_SERVICE_DRIVER:
                pcr_index = 2;
                event_type = EV_EFI_BOOT_SERVICES_DRIVER;
                break;
        case IMAGE_SUBSYSTEM_EFI_RUNTIME_DRIVER:
                pcr_index = 2;
                event_type = EV_EFI_RUNTIME_SERVICES_DRIVER;
                break;
        default:
                return EFI_UNSUPPORTED;
        }

        ret = tcg2_hash_pe_image(efi, efi_size, &digest_list);
        if (ret != EFI_SUCCESS)

                return ret;

        ret = tcg2_pcr_extend(dev, pcr_index, &digest_list);
        if (ret != EFI_SUCCESS)
                return ret;

        ret = efi_search_protocol(&handle->header,
                                  &efi_guid_loaded_image_device_path, &handler);
        if (ret != EFI_SUCCESS)
                return ret;

        device_path = handler->protocol_interface;
        device_path_length = efi_dp_size(device_path);
        if (device_path_length > 0) {
                /* add end node size */
                device_path_length += sizeof(struct efi_device_path);
        }
        event_size = sizeof(struct uefi_image_load_event) + device_path_length;
        image_load_event = calloc(1, event_size);
        if (!image_load_event)
                return EFI_OUT_OF_RESOURCES;

        image_load_event->image_location_in_memory = (uintptr_t)efi;
        image_load_event->image_length_in_memory = efi_size;
        image_load_event->length_of_device_path = device_path_length;

        dos = (IMAGE_DOS_HEADER *)efi;
        nt = (IMAGE_NT_HEADERS32 *)(efi + dos->e_lfanew);
        if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR64_MAGIC) {
                IMAGE_NT_HEADERS64 *nt64 = (IMAGE_NT_HEADERS64 *)nt;

                image_load_event->image_link_time_address =
                                nt64->OptionalHeader.ImageBase;
        } else if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
                image_load_event->image_link_time_address =
                                nt->OptionalHeader.ImageBase;
        } else {
                ret = EFI_INVALID_PARAMETER;
                goto out;
        }

        /* device_path_length might be zero */
        memcpy(image_load_event->device_path, device_path, device_path_length);

        ret = tcg2_agile_log_append(pcr_index, event_type, &digest_list,
                                    event_size, (u8 *)image_load_event);

out:
        free(image_load_event);

        return ret;
}

/**
 * efi_tcg2_hash_log_extend_event() - extend and optionally log events
 *
 * @this:                       TCG2 protocol instance
 * @flags:                      bitmap providing additional information on the
 *                              operation
 * @data_to_hash:               physical address of the start of the data buffer
 *                              to be hashed
 * @data_to_hash_len:           the length in bytes of the buffer referenced by
 *                              data_to_hash
 * @efi_tcg_event:              pointer to data buffer containing information
 *                              about the event
 *
 * Return:      status code
 */
static efi_status_t EFIAPI
efi_tcg2_hash_log_extend_event(struct efi_tcg2_protocol *this, u64 flags,
                               u64 data_to_hash, u64 data_to_hash_len,
                               struct efi_tcg2_event *efi_tcg_event)
{
        struct udevice *dev;
        efi_status_t ret;
        u32 event_type, pcr_index, event_size;
        struct tpml_digest_values digest_list;

        EFI_ENTRY("%p, %llu, %llu, %llu, %p", this, flags, data_to_hash,
                  data_to_hash_len, efi_tcg_event);

        if (!this || !data_to_hash || !efi_tcg_event) {
                ret = EFI_INVALID_PARAMETER;
                goto out;
        }

        ret = platform_get_tpm2_device(&dev);
        if (ret != EFI_SUCCESS)
                goto out;

        if (efi_tcg_event->size < efi_tcg_event->header.header_size +
            sizeof(u32)) {
                ret = EFI_INVALID_PARAMETER;
                goto out;
        }

        if (efi_tcg_event->header.pcr_index > EFI_TCG2_MAX_PCR_INDEX) {
                ret = EFI_INVALID_PARAMETER;
                goto out;
        }

        /*
         * if PE_COFF_IMAGE is set we need to make sure the image is not
         * corrupted, verify it and hash the PE/COFF image in accordance with
         * the procedure specified in "Calculating the PE Image Hash"
         * section of the "Windows Authenticode Portable Executable Signature
         * Format"
         */
        if (flags & PE_COFF_IMAGE) {
                IMAGE_NT_HEADERS32 *nt;

                ret = efi_check_pe((void *)(uintptr_t)data_to_hash,
                                   data_to_hash_len, (void **)&nt);
                if (ret != EFI_SUCCESS) {
                        log_err("Not a valid PE-COFF file\n");
                        ret = EFI_UNSUPPORTED;
                        goto out;
                }
                ret = tcg2_hash_pe_image((void *)(uintptr_t)data_to_hash,
                                         data_to_hash_len, &digest_list);
        } else {
                ret = tcg2_create_digest((u8 *)(uintptr_t)data_to_hash,
                                         data_to_hash_len, &digest_list);
        }

        if (ret != EFI_SUCCESS)
                goto out;

        pcr_index = efi_tcg_event->header.pcr_index;
        event_type = efi_tcg_event->header.event_type;

        ret = tcg2_pcr_extend(dev, pcr_index, &digest_list);
        if (ret != EFI_SUCCESS)
                goto out;

        if (flags & EFI_TCG2_EXTEND_ONLY) {
                if (event_log.truncated)
                        ret = EFI_VOLUME_FULL;
                goto out;
        }

        /*
         * The efi_tcg_event size includes the size component and the
         * headersize
         */
        event_size = efi_tcg_event->size - sizeof(efi_tcg_event->size) -
                efi_tcg_event->header.header_size;
        ret = tcg2_agile_log_append(pcr_index, event_type, &digest_list,
                                    event_size, efi_tcg_event->event);
out:
        return EFI_EXIT(ret);
}

/**
 * efi_tcg2_submit_command() - Send command to the TPM
 *
 * @this:                       TCG2 protocol instance
 * @input_param_block_size:     size of the TPM input parameter block
 * @input_param_block:          pointer to the TPM input parameter block
 * @output_param_block_size:    size of the TPM output parameter block
 * @output_param_block:         pointer to the TPM output parameter block
 *
 * Return:      status code
 */
static efi_status_t EFIAPI
efi_tcg2_submit_command(struct efi_tcg2_protocol *this,
                        u32 input_param_block_size,
                        u8 *input_param_block,
                        u32 output_param_block_size,
                        u8 *output_param_block)
{
        struct udevice *dev;
        efi_status_t ret;
        u32 rc;
        size_t resp_buf_size = output_param_block_size;

        EFI_ENTRY("%p, %u, %p, %u, %p", this, input_param_block_size,
                  input_param_block, output_param_block_size, output_param_block);

        if (!this || !input_param_block || !input_param_block_size) {
                ret = EFI_INVALID_PARAMETER;
                goto out;
        }

        ret = platform_get_tpm2_device(&dev);
        if (ret != EFI_SUCCESS)
                goto out;

        rc = tpm2_submit_command(dev, input_param_block,
                                 output_param_block, &resp_buf_size);
        if (rc) {
                ret = (rc == -ENOSPC) ? EFI_OUT_OF_RESOURCES : EFI_DEVICE_ERROR;

                goto out;
        }

out:
        return EFI_EXIT(ret);
}

/**
 * efi_tcg2_get_active_pcr_banks() - returns the currently active PCR banks
 *
 * @this:                       TCG2 protocol instance
 * @active_pcr_banks:           pointer for receiving the bitmap of currently
 *                              active PCR banks
 *
 * Return:      status code
 */
static efi_status_t EFIAPI
efi_tcg2_get_active_pcr_banks(struct efi_tcg2_protocol *this,
                              u32 *active_pcr_banks)
{
        efi_status_t ret;

        if (!this || !active_pcr_banks) {
                ret = EFI_INVALID_PARAMETER;
                goto out;
        }

        EFI_ENTRY("%p, %p", this, active_pcr_banks);
        ret = __get_active_pcr_banks(active_pcr_banks);

out:
        return EFI_EXIT(ret);
}

/**
 * efi_tcg2_set_active_pcr_banks() - sets the currently active PCR banks
 *
 * @this:                       TCG2 protocol instance
 * @active_pcr_banks:           bitmap of the requested active PCR banks
 *
 * Return:      status code
 */
static efi_status_t EFIAPI
efi_tcg2_set_active_pcr_banks(__maybe_unused struct efi_tcg2_protocol *this,
                              u32 __maybe_unused active_pcr_banks)
{
        return EFI_UNSUPPORTED;
}

/**
 * efi_tcg2_get_result_of_set_active_pcr_banks() - retrieve result for previous
 *                                                 set_active_pcr_banks()
 *
 * @this:                       TCG2 protocol instance
 * @operation_present:          non-zero value to indicate a
 *                              set_active_pcr_banks operation was
 *                              invoked during last boot
 * @response:                   result value could be returned
 *
 * Return:      status code
 */
static efi_status_t EFIAPI
efi_tcg2_get_result_of_set_active_pcr_banks(__maybe_unused struct efi_tcg2_protocol *this,
                                            u32 __maybe_unused *operation_present,
                                            u32 __maybe_unused *response)
{
        return EFI_UNSUPPORTED;
}

static const struct efi_tcg2_protocol efi_tcg2_protocol = {
        .get_capability = efi_tcg2_get_capability,
        .get_eventlog = efi_tcg2_get_eventlog,
        .hash_log_extend_event = efi_tcg2_hash_log_extend_event,
        .submit_command = efi_tcg2_submit_command,
        .get_active_pcr_banks = efi_tcg2_get_active_pcr_banks,
        .set_active_pcr_banks = efi_tcg2_set_active_pcr_banks,
        .get_result_of_set_active_pcr_banks = efi_tcg2_get_result_of_set_active_pcr_banks,
};

/**
 * parse_event_log_header() -  Parse and verify the event log header fields
 *
 * @buffer:                     Pointer to the start of the eventlog
 * @size:                       Size of the eventlog
 * @pos:                        Return offset of the next event in buffer right
 *                              after the event header i.e specID
 *
 * Return:      status code
 */
static efi_status_t parse_event_log_header(void *buffer, u32 size, u32 *pos)
{
        struct tcg_pcr_event *event_header = (struct tcg_pcr_event *)buffer;
        int i = 0;

        if (size < sizeof(*event_header))
                return EFI_COMPROMISED_DATA;

        if (get_unaligned_le32(&event_header->pcr_index) != 0 ||
            get_unaligned_le32(&event_header->event_type) != EV_NO_ACTION)
                return EFI_COMPROMISED_DATA;

        for (i = 0; i < sizeof(event_header->digest); i++) {
                if (event_header->digest[i])
                        return EFI_COMPROMISED_DATA;
        }

        *pos += sizeof(*event_header);

        return EFI_SUCCESS;
}

/**
 * parse_specid_event() -  Parse and verify the specID Event in the eventlog
 *
 * @dev:                udevice
 * @buffer:             Pointer to the start of the eventlog
 * @log_size:           Size of the eventlog
 * @pos:                [in] Offset of specID event in the eventlog buffer
 *                      [out] Return offset of the next event in the buffer
 *                      after the specID
 * @digest_list:        list of digests in the event
 *
 * Return:              status code
 * @pos                 Offset in the eventlog where the specID event ends
 * @digest_list:        list of digests in the event
 */
static efi_status_t parse_specid_event(struct udevice *dev, void *buffer,
                                       u32 log_size, u32 *pos,
                                       struct tpml_digest_values *digest_list)
{
        struct tcg_efi_spec_id_event *spec_event;
        struct tcg_pcr_event *event_header = (struct tcg_pcr_event *)buffer;
        size_t spec_event_size;
        u32 active = 0, supported = 0, pcr_count = 0, alg_count = 0;
        u32 spec_active = 0;
        u16 hash_alg;
        u8 vendor_sz;
        int err, i;

        if (*pos >= log_size || (*pos + sizeof(*spec_event)) > log_size)
                return EFI_COMPROMISED_DATA;

        /* Check specID event data */
        spec_event = (struct tcg_efi_spec_id_event *)((uintptr_t)buffer + *pos);
        /* Check for signature */
        if (memcmp(spec_event->signature, TCG_EFI_SPEC_ID_EVENT_SIGNATURE_03,
                   sizeof(TCG_EFI_SPEC_ID_EVENT_SIGNATURE_03))) {
                log_err("specID Event: Signature mismatch\n");
                return EFI_COMPROMISED_DATA;
        }

        if (spec_event->spec_version_minor !=
                        TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MINOR_TPM2 ||
            spec_event->spec_version_major !=
                        TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MAJOR_TPM2)
                return EFI_COMPROMISED_DATA;

        if (spec_event->number_of_algorithms > MAX_HASH_COUNT ||
            spec_event->number_of_algorithms < 1) {
                log_err("specID Event: Number of algorithms incorrect\n");
                return EFI_COMPROMISED_DATA;
        }

        alg_count = spec_event->number_of_algorithms;

        err = tpm2_get_pcr_info(dev, &supported, &active, &pcr_count);
        if (err)
                return EFI_DEVICE_ERROR;

        digest_list->count = 0;
        /*
         * We have to take care that the sequence of algorithms that we record
         * in digest_list matches the sequence in eventlog.
         */
        for (i = 0; i < alg_count; i++) {
                hash_alg =
                  get_unaligned_le16(&spec_event->digest_sizes[i].algorithm_id);

                if (!(supported & alg_to_mask(hash_alg))) {
                        log_err("specID Event: Unsupported algorithm\n");
                        return EFI_COMPROMISED_DATA;
                }
                digest_list->digests[digest_list->count++].hash_alg = hash_alg;

                spec_active |= alg_to_mask(hash_alg);
        }

        /*
         * TCG specification expects the event log to have hashes for all
         * active PCR's
         */
        if (spec_active != active) {
                /*
                 * Previous stage bootloader should know all the active PCR's
                 * and use them in the Eventlog.
                 */
                log_err("specID Event: All active hash alg not present\n");
                return EFI_COMPROMISED_DATA;
        }

        /*
         * the size of the spec event and placement of vendor_info_size
         * depends on supported algoriths
         */
        spec_event_size =
                offsetof(struct tcg_efi_spec_id_event, digest_sizes) +
                alg_count * sizeof(spec_event->digest_sizes[0]);

        if (*pos + spec_event_size >= log_size)
                return EFI_COMPROMISED_DATA;

        vendor_sz = *(uint8_t *)((uintptr_t)buffer + *pos + spec_event_size);

        spec_event_size += sizeof(vendor_sz) + vendor_sz;
        *pos += spec_event_size;

        if (get_unaligned_le32(&event_header->event_size) != spec_event_size) {
                log_err("specID event: header event size mismatch\n");
                /* Right way to handle this can be to call SetActive PCR's */
                return EFI_COMPROMISED_DATA;
        }

        return EFI_SUCCESS;
}

/**
 * tcg2_parse_event() -  Parse the event in the eventlog
 *
 * @dev:                udevice
 * @buffer:             Pointer to the start of the eventlog
 * @log_size:           Size of the eventlog
 * @offset:             [in] Offset of the event in the eventlog buffer
 *                      [out] Return offset of the next event in the buffer
 * @digest_list:        list of digests in the event
 * @pcr                 Index of the PCR in the event
 *
 * Return:              status code
 */
static efi_status_t tcg2_parse_event(struct udevice *dev, void *buffer,
                                     u32 log_size, u32 *offset,
                                     struct tpml_digest_values *digest_list,
                                     u32 *pcr)
{
        struct tcg_pcr_event2 *event = NULL;
        u32 count, size, event_size;
        size_t pos;

        event_size = tcg_event_final_size(digest_list);
        if (*offset >= log_size || *offset + event_size > log_size) {
                log_err("Event exceeds log size\n");
                return EFI_COMPROMISED_DATA;
        }

        event = (struct tcg_pcr_event2 *)((uintptr_t)buffer + *offset);
        *pcr = get_unaligned_le32(&event->pcr_index);

        /* get the count */
        count = get_unaligned_le32(&event->digests.count);
        if (count != digest_list->count)
                return EFI_COMPROMISED_DATA;

        pos = offsetof(struct tcg_pcr_event2, digests);
        pos += offsetof(struct tpml_digest_values, digests);

        for (int i = 0; i < digest_list->count; i++) {
                u16 alg;
                u16 hash_alg = digest_list->digests[i].hash_alg;
                u8 *digest = (u8 *)&digest_list->digests[i].digest;

                alg = get_unaligned_le16((void *)((uintptr_t)event + pos));

                if (alg != hash_alg)
                        return EFI_COMPROMISED_DATA;

                pos += offsetof(struct tpmt_ha, digest);
                memcpy(digest, (void *)((uintptr_t)event + pos), alg_to_len(hash_alg));
                pos += alg_to_len(hash_alg);
        }

        size = get_unaligned_le32((void *)((uintptr_t)event + pos));
        event_size += size;
        pos += sizeof(u32); /* tcg_pcr_event2 event_size*/
        pos += size;

        /* make sure the calculated buffer is what we checked against */
        if (pos != event_size)
                return EFI_COMPROMISED_DATA;

        if (pos > log_size)
                return EFI_COMPROMISED_DATA;

        *offset += pos;

        return EFI_SUCCESS;
}

/**
 * tcg2_get_fw_eventlog() -  Get the eventlog address and size
 *
 * If the previous firmware has passed some eventlog, this function get it's
 * location and check for it's validity.
 *
 * @dev:                udevice
 * @log_buffer:         eventlog address
 * @log_sz:             eventlog size
 *
 * Return:      status code
 */
static efi_status_t tcg2_get_fw_eventlog(struct udevice *dev, void *log_buffer,
                                         size_t *log_sz)
{
        struct tpml_digest_values digest_list;
        void *buffer;
        efi_status_t ret;
        u32 pcr, pos;
        u64 base;
        u32 sz;
        bool extend_pcr = false;
        int i;

        ret = platform_get_eventlog(dev, &base, &sz);
        if (ret != EFI_SUCCESS)
                return ret;

        if (sz > TPM2_EVENT_LOG_SIZE)
                return EFI_VOLUME_FULL;

        buffer = (void *)(uintptr_t)base;
        pos = 0;
        /* Parse the eventlog to check for its validity */
        ret = parse_event_log_header(buffer, sz, &pos);
        if (ret)
                return ret;

        ret = parse_specid_event(dev, buffer, sz, &pos, &digest_list);
        if (ret) {
                log_err("Error parsing SPEC ID Event\n");
                return ret;
        }

        ret = tcg2_pcr_read(dev, 0, &digest_list);
        if (ret) {
                log_err("Error reading PCR 0\n");
                return ret;
        }

        /*
         * If PCR0 is 0, previous firmware didn't have the capability
         * to extend the PCR. In this scenario, extend the PCR as
         * the eventlog is parsed.
         */
        for (i = 0; i < digest_list.count; i++) {
                u8 hash_buf[TPM2_SHA512_DIGEST_SIZE] = { 0 };
                u16 hash_alg = digest_list.digests[i].hash_alg;

                if (!memcmp((u8 *)&digest_list.digests[i].digest, hash_buf,
                            alg_to_len(hash_alg)))
                        extend_pcr = true;
        }

        while (pos < sz) {
                ret = tcg2_parse_event(dev, buffer, sz, &pos, &digest_list,
                                       &pcr);
                if (ret) {
                        log_err("Error parsing event\n");
                        return ret;
                }
                if (extend_pcr) {
                        ret = tcg2_pcr_extend(dev, pcr, &digest_list);
                        if (ret != EFI_SUCCESS) {
                                log_err("Error in extending PCR\n");
                                return ret;
                        }

                        /* Clear the digest for next event */
                        for (i = 0; i < digest_list.count; i++) {
                                u16 hash_alg = digest_list.digests[i].hash_alg;
                                u8 *digest =
                                   (u8 *)&digest_list.digests[i].digest;

                                memset(digest, 0, alg_to_len(hash_alg));
                        }
                }
        }

        memcpy(log_buffer, buffer, sz);
        *log_sz = sz;

        return ret;
}

/**
 * create_specid_event() - Create the first event in the eventlog
 *
 * @dev:                        tpm device
 * @event_header:               Pointer to the final event header
 * @event_size:                 final spec event size
 *
 * Return:      status code
 */
static efi_status_t create_specid_event(struct udevice *dev, void *buffer,
                                        size_t *event_size)
{
        struct tcg_efi_spec_id_event *spec_event;
        size_t spec_event_size;
        efi_status_t ret = EFI_DEVICE_ERROR;
        u32 active = 0, supported = 0, pcr_count = 0, alg_count = 0;
        int err;
        size_t i;

        /*
         * Create Spec event. This needs to be the first event in the log
         * according to the TCG EFI protocol spec
         */

        /* Setup specID event data */
        spec_event = (struct tcg_efi_spec_id_event *)buffer;
        memcpy(spec_event->signature, TCG_EFI_SPEC_ID_EVENT_SIGNATURE_03,
               sizeof(spec_event->signature));
        put_unaligned_le32(0, &spec_event->platform_class); /* type client */
        spec_event->spec_version_minor =
                TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MINOR_TPM2;
        spec_event->spec_version_major =
                TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MAJOR_TPM2;
        spec_event->spec_errata =
                TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_ERRATA_TPM2;
        spec_event->uintn_size = sizeof(efi_uintn_t) / sizeof(u32);

        err = tpm2_get_pcr_info(dev, &supported, &active, &pcr_count);

        if (err)
                goto out;

        for (i = 0; i < pcr_count; i++) {
                u16 hash_alg = hash_algo_list[i].hash_alg;
                u16 hash_len = hash_algo_list[i].hash_len;

                if (active & alg_to_mask(hash_alg)) {
                        put_unaligned_le16(hash_alg,
                                           &spec_event->digest_sizes[alg_count].algorithm_id);
                        put_unaligned_le16(hash_len,
                                           &spec_event->digest_sizes[alg_count].digest_size);
                        alg_count++;
                }
        }

        spec_event->number_of_algorithms = alg_count;
        if (spec_event->number_of_algorithms > MAX_HASH_COUNT ||
            spec_event->number_of_algorithms < 1)
                goto out;

        /*
         * the size of the spec event and placement of vendor_info_size
         * depends on supported algoriths
         */
        spec_event_size =
                offsetof(struct tcg_efi_spec_id_event, digest_sizes) +
                spec_event->number_of_algorithms * sizeof(spec_event->digest_sizes[0]);
        /* no vendor info for us */
        memset(buffer + spec_event_size, 0, 1);
        /* add a byte for vendor_info_size in the spec event */
        spec_event_size += 1;
        *event_size = spec_event_size;

        return EFI_SUCCESS;

out:
        return ret;
}

/**
 * tcg2_uninit - remove the final event table and free efi memory on failures
 */
void tcg2_uninit(void)
{
        efi_status_t ret;

        ret = efi_install_configuration_table(&efi_guid_final_events, NULL);
        if (ret != EFI_SUCCESS)
                log_err("Failed to delete final events config table\n");

        efi_free_pool(event_log.buffer);
        event_log.buffer = NULL;
        efi_free_pool(event_log.final_buffer);
        event_log.final_buffer = NULL;

        if (!is_tcg2_protocol_installed())
                return;

        ret = efi_remove_protocol(efi_root, &efi_guid_tcg2_protocol,
                                  (void *)&efi_tcg2_protocol);
        if (ret != EFI_SUCCESS)
                log_err("Failed to remove EFI TCG2 protocol\n");
}

/**
 * create_final_event() - Create the final event and install the config
 *                      defined by the TCG EFI spec
 */
static efi_status_t create_final_event(void)
{
        struct efi_tcg2_final_events_table *final_event;
        efi_status_t ret;

        /*
         * All events generated after the invocation of
         * EFI_TCG2_GET_EVENT_LOGS need to be stored in an instance of an
         * EFI_CONFIGURATION_TABLE
         */
        ret = efi_allocate_pool(EFI_ACPI_MEMORY_NVS, TPM2_EVENT_LOG_SIZE,
                                &event_log.final_buffer);
        if (ret != EFI_SUCCESS)
                goto out;

        memset(event_log.final_buffer, 0xff, TPM2_EVENT_LOG_SIZE);
        final_event = event_log.final_buffer;
        final_event->number_of_events = 0;
        final_event->version = EFI_TCG2_FINAL_EVENTS_TABLE_VERSION;
        event_log.final_pos = sizeof(*final_event);
        ret = efi_install_configuration_table(&efi_guid_final_events,
                                              final_event);
        if (ret != EFI_SUCCESS) {
                efi_free_pool(event_log.final_buffer);
                event_log.final_buffer = NULL;
        }

out:
        return ret;
}

/**
 * tcg2_measure_event() - common function to add event log and extend PCR
 *
 * @dev:                TPM device
 * @pcr_index:          PCR index
 * @event_type:         type of event added
 * @size:               event size
 * @event:              event data
 *
 * Return:      status code
 */
static efi_status_t
tcg2_measure_event(struct udevice *dev, u32 pcr_index, u32 event_type,
                   u32 size, u8 event[])
{
        struct tpml_digest_values digest_list;
        efi_status_t ret;

        ret = tcg2_create_digest(event, size, &digest_list);
        if (ret != EFI_SUCCESS)
                goto out;

        ret = tcg2_pcr_extend(dev, pcr_index, &digest_list);
        if (ret != EFI_SUCCESS)
                goto out;

        ret = tcg2_agile_log_append(pcr_index, event_type, &digest_list,
                                    size, event);

out:
        return ret;
}

/**
 * efi_append_scrtm_version - Append an S-CRTM EV_S_CRTM_VERSION event on the
 *                            eventlog and extend the PCRs
 *
 * @dev:        TPM device
 *
 * @Return:     status code
 */
static efi_status_t efi_append_scrtm_version(struct udevice *dev)
{
        efi_status_t ret;

        ret = tcg2_measure_event(dev, 0, EV_S_CRTM_VERSION,
                                 strlen(version_string) + 1,
                                 (u8 *)version_string);

        return ret;
}

/**
 * efi_init_event_log() - initialize an eventlog
 *
 * Return:              status code
 */
static efi_status_t efi_init_event_log(void)
{
        /*
         * vendor_info_size is currently set to 0, we need to change the length
         * and allocate the flexible array member if this changes
         */
        struct tcg_pcr_event *event_header = NULL;
        struct udevice *dev;
        size_t spec_event_size;
        efi_status_t ret;

        ret = platform_get_tpm2_device(&dev);
        if (ret != EFI_SUCCESS)
                return ret;

        ret = efi_allocate_pool(EFI_BOOT_SERVICES_DATA, TPM2_EVENT_LOG_SIZE,
                                (void **)&event_log.buffer);
        if (ret != EFI_SUCCESS)
                return ret;

        /*
         * initialize log area as 0xff so the OS can easily figure out the
         * last log entry
         */
        memset(event_log.buffer, 0xff, TPM2_EVENT_LOG_SIZE);

        /*
         * The log header is defined to be in SHA1 event log entry format.
         * Setup event header
         */
        event_header =  (struct tcg_pcr_event *)event_log.buffer;
        event_log.pos = 0;
        event_log.last_event_size = 0;
        event_log.get_event_called = false;
        event_log.ebs_called = false;
        event_log.truncated = false;

        /*
         * Check if earlier firmware have passed any eventlog. Different
         * platforms can use different ways to do so.
         */
        ret = tcg2_get_fw_eventlog(dev, event_log.buffer, &event_log.pos);
        /*
         * If earlier firmware hasn't passed any eventlog, go ahead and
         * create the eventlog header.
         */
        if (ret == EFI_NOT_FOUND) {
                put_unaligned_le32(0, &event_header->pcr_index);
                put_unaligned_le32(EV_NO_ACTION, &event_header->event_type);
                memset(&event_header->digest, 0, sizeof(event_header->digest));
                ret = create_specid_event(dev,
                                          (void *)((uintptr_t)event_log.buffer +
                                                   sizeof(*event_header)),
                                          &spec_event_size);
                if (ret != EFI_SUCCESS)
                        goto free_pool;
                put_unaligned_le32(spec_event_size, &event_header->event_size);
                event_log.pos = spec_event_size + sizeof(*event_header);
                event_log.last_event_size = event_log.pos;

                /*
                 * Add SCRTM version to the log if previous firmmware
                 * doesn't pass an eventlog.
                 */
                ret = efi_append_scrtm_version(dev);
        }

        if (ret != EFI_SUCCESS)
                goto free_pool;

        ret = create_final_event();
        if (ret != EFI_SUCCESS)
                goto free_pool;

        return ret;

free_pool:
        efi_free_pool(event_log.buffer);
        event_log.buffer = NULL;
        return ret;
}

/**
 * tcg2_measure_variable() - add variable event log and extend PCR
 *
 * @dev:                TPM device
 * @pcr_index:          PCR index
 * @event_type:         type of event added
 * @var_name:           variable name
 * @guid:               guid
 * @data_size:          variable data size
 * @data:               variable data
 *
 * Return:      status code
 */
static efi_status_t tcg2_measure_variable(struct udevice *dev, u32 pcr_index,
                                          u32 event_type, const u16 *var_name,
                                          const efi_guid_t *guid,
                                          efi_uintn_t data_size, u8 *data)
{
        u32 event_size;
        efi_status_t ret;
        struct efi_tcg2_uefi_variable_data *event;

        event_size = sizeof(event->variable_name) +
                     sizeof(event->unicode_name_length) +
                     sizeof(event->variable_data_length) +
                     (u16_strlen(var_name) * sizeof(u16)) + data_size;
        event = malloc(event_size);
        if (!event)
                return EFI_OUT_OF_RESOURCES;

        guidcpy(&event->variable_name, guid);
        event->unicode_name_length = u16_strlen(var_name);
        event->variable_data_length = data_size;
        memcpy(event->unicode_name, var_name,
               (event->unicode_name_length * sizeof(u16)));
        if (data) {
                memcpy((u16 *)event->unicode_name + event->unicode_name_length,
                       data, data_size);
        }
        ret = tcg2_measure_event(dev, pcr_index, event_type, event_size,
                                 (u8 *)event);
        free(event);
        return ret;
}

/**
 * tcg2_measure_boot_variable() - measure boot variables
 *
 * @dev:        TPM device
 *
 * Return:      status code
 */
static efi_status_t tcg2_measure_boot_variable(struct udevice *dev)
{
        u16 *boot_order;
        u16 *boot_index;
        u16 var_name[] = u"BootOrder";
        u16 boot_name[] = u"Boot####";
        u8 *bootvar;
        efi_uintn_t var_data_size;
        u32 count, i;
        efi_status_t ret;

        boot_order = efi_get_var(var_name, &efi_global_variable_guid,
                                 &var_data_size);
        if (!boot_order) {
                /* If "BootOrder" is not defined, skip the boot variable measurement */
                return EFI_SUCCESS;
        }

        ret = tcg2_measure_variable(dev, 1, EV_EFI_VARIABLE_BOOT2, var_name,
                                    &efi_global_variable_guid, var_data_size,
                                    (u8 *)boot_order);
        if (ret != EFI_SUCCESS)
                goto error;

        count = var_data_size / sizeof(*boot_order);
        boot_index = boot_order;
        for (i = 0; i < count; i++) {
                efi_create_indexed_name(boot_name, sizeof(boot_name),
                                        "Boot", *boot_index++);

                bootvar = efi_get_var(boot_name, &efi_global_variable_guid,
                                      &var_data_size);

                if (!bootvar) {
                        log_debug("%ls not found\n", boot_name);
                        continue;
                }

                ret = tcg2_measure_variable(dev, 1, EV_EFI_VARIABLE_BOOT2,
                                            boot_name,
                                            &efi_global_variable_guid,
                                            var_data_size, bootvar);
                free(bootvar);
                if (ret != EFI_SUCCESS)
                        goto error;
        }

error:
        free(boot_order);
        return ret;
}

/**
 * tcg2_measure_smbios() - measure smbios table
 *
 * @dev:        TPM device
 * @entry:      pointer to the smbios_entry structure
 *
 * Return:      status code
 */
static efi_status_t
tcg2_measure_smbios(struct udevice *dev,
                    const struct smbios_entry *entry)
{
        efi_status_t ret;
        struct smbios_header *smbios_copy;
        struct smbios_handoff_table_pointers2 *event = NULL;
        u32 event_size;

        /*
         * TCG PC Client PFP Spec says
         * "SMBIOS structures that contain static configuration information
         * (e.g. Platform Manufacturer Enterprise Number assigned by IANA,
         * platform model number, Vendor and Device IDs for each SMBIOS table)
         * that is relevant to the security of the platform MUST be measured".
         * Device dependent parameters such as serial number are cleared to
         * zero or spaces for the measurement.
         */
        event_size = sizeof(struct smbios_handoff_table_pointers2) +
                     FIELD_SIZEOF(struct efi_configuration_table, guid) +
                     entry->struct_table_length;
        event = calloc(1, event_size);
        if (!event) {
                ret = EFI_OUT_OF_RESOURCES;
                goto out;
        }

        event->table_description_size = sizeof(SMBIOS_HANDOFF_TABLE_DESC);
        memcpy(event->table_description, SMBIOS_HANDOFF_TABLE_DESC,
               sizeof(SMBIOS_HANDOFF_TABLE_DESC));
        put_unaligned_le64(1, &event->number_of_tables);
        guidcpy(&event->table_entry[0].guid, &smbios_guid);
        smbios_copy = (struct smbios_header *)((uintptr_t)&event->table_entry[0].table);
        memcpy(&event->table_entry[0].table,
               (void *)((uintptr_t)entry->struct_table_address),
               entry->struct_table_length);

        smbios_prepare_measurement(entry, smbios_copy);

        ret = tcg2_measure_event(dev, 1, EV_EFI_HANDOFF_TABLES2, event_size,
                                 (u8 *)event);
        if (ret != EFI_SUCCESS)
                goto out;

out:
        free(event);

        return ret;
}

/**
 * find_smbios_table() - find smbios table
 *
 * Return:      pointer to the smbios table
 */
static void *find_smbios_table(void)
{
        u32 i;

        for (i = 0; i < systab.nr_tables; i++) {
                if (!guidcmp(&smbios_guid, &systab.tables[i].guid))
                        return systab.tables[i].table;
        }

        return NULL;
}

/**
 * tcg2_measure_gpt_table() - measure gpt table
 *
 * @dev:                TPM device
 * @loaded_image:       handle to the loaded image
 *
 * Return:      status code
 */
static efi_status_t
tcg2_measure_gpt_data(struct udevice *dev,
                      struct efi_loaded_image_obj *loaded_image)
{
        efi_status_t ret;
        efi_handle_t handle;
        struct efi_handler *dp_handler, *io_handler;
        struct efi_device_path *orig_device_path;
        struct efi_device_path *device_path;
        struct efi_device_path *dp;
        struct efi_block_io *block_io;
        struct efi_gpt_data *event = NULL;
        efi_guid_t null_guid = NULL_GUID;
        gpt_header *gpt_h;
        gpt_entry *entry = NULL;
        gpt_entry *gpt_e;
        u32 num_of_valid_entry = 0;
        u32 event_size;
        u32 i;
        u32 total_gpt_entry_size;

        ret = efi_search_protocol(&loaded_image->header,
                                  &efi_guid_loaded_image_device_path,
                                  &dp_handler);
        if (ret != EFI_SUCCESS)
                return ret;

        orig_device_path = dp_handler->protocol_interface;
        if (!orig_device_path) /* no device path, skip GPT measurement */
                return EFI_SUCCESS;

        device_path = efi_dp_dup(orig_device_path);
        if (!device_path)
                return EFI_OUT_OF_RESOURCES;

        dp = search_gpt_dp_node(device_path);
        if (!dp) {
                /* no GPT device path node found, skip GPT measurement */
                ret = EFI_SUCCESS;
                goto out1;
        }

        /* read GPT header */
        dp->type = DEVICE_PATH_TYPE_END;
        dp->sub_type = DEVICE_PATH_SUB_TYPE_END;
        dp = device_path;
        ret = EFI_CALL(systab.boottime->locate_device_path(&efi_block_io_guid,
                                                           &dp, &handle));
        if (ret != EFI_SUCCESS)
                goto out1;

        ret = efi_search_protocol(handle, &efi_block_io_guid, &io_handler);
        if (ret != EFI_SUCCESS)
                goto out1;
        block_io = io_handler->protocol_interface;

        gpt_h = memalign(block_io->media->io_align, block_io->media->block_size);
        if (!gpt_h) {
                ret = EFI_OUT_OF_RESOURCES;
                goto out2;
        }

        ret = block_io->read_blocks(block_io, block_io->media->media_id, 1,
                                    block_io->media->block_size, gpt_h);
        if (ret != EFI_SUCCESS)
                goto out2;

        /* read GPT entry */
        total_gpt_entry_size = gpt_h->num_partition_entries *
                               gpt_h->sizeof_partition_entry;
        entry = memalign(block_io->media->io_align, total_gpt_entry_size);
        if (!entry) {
                ret = EFI_OUT_OF_RESOURCES;
                goto out2;
        }

        ret = block_io->read_blocks(block_io, block_io->media->media_id,
                                    gpt_h->partition_entry_lba,
                                    total_gpt_entry_size, entry);
        if (ret != EFI_SUCCESS)
                goto out2;

        /* count valid GPT entry */
        gpt_e = entry;
        for (i = 0; i < gpt_h->num_partition_entries; i++) {
                if (guidcmp(&null_guid, &gpt_e->partition_type_guid))
                        num_of_valid_entry++;

                gpt_e = (gpt_entry *)((u8 *)gpt_e + gpt_h->sizeof_partition_entry);
        }

        /* prepare event data for measurement */
        event_size = sizeof(struct efi_gpt_data) +
                (num_of_valid_entry * gpt_h->sizeof_partition_entry);
        event = calloc(1, event_size);
        if (!event) {
                ret = EFI_OUT_OF_RESOURCES;
                goto out2;
        }
        memcpy(event, gpt_h, sizeof(gpt_header));
        put_unaligned_le64(num_of_valid_entry, &event->number_of_partitions);

        /* copy valid GPT entry */
        gpt_e = entry;
        num_of_valid_entry = 0;
        for (i = 0; i < gpt_h->num_partition_entries; i++) {
                if (guidcmp(&null_guid, &gpt_e->partition_type_guid)) {
                        memcpy((u8 *)event->partitions +
                               (num_of_valid_entry * gpt_h->sizeof_partition_entry),
                               gpt_e, gpt_h->sizeof_partition_entry);
                        num_of_valid_entry++;
                }

                gpt_e = (gpt_entry *)((u8 *)gpt_e + gpt_h->sizeof_partition_entry);
        }

        ret = tcg2_measure_event(dev, 5, EV_EFI_GPT_EVENT, event_size, (u8 *)event);

out2:
        free(gpt_h);
        free(entry);
        free(event);
out1:
        efi_free_pool(device_path);

        return ret;
}

/**
 * efi_tcg2_measure_efi_app_invocation() - measure efi app invocation
 *
 * Return:      status code
 */
efi_status_t efi_tcg2_measure_efi_app_invocation(struct efi_loaded_image_obj *handle)
{
        efi_status_t ret;
        u32 pcr_index;
        struct udevice *dev;
        u32 event = 0;
        struct smbios_entry *entry;

        if (!is_tcg2_protocol_installed())
                return EFI_SUCCESS;

        if (tcg2_efi_app_invoked)
                return EFI_SUCCESS;

        ret = platform_get_tpm2_device(&dev);
        if (ret != EFI_SUCCESS)
                return EFI_SECURITY_VIOLATION;

        ret = tcg2_measure_boot_variable(dev);
        if (ret != EFI_SUCCESS)
                goto out;

        ret = tcg2_measure_event(dev, 4, EV_EFI_ACTION,
                                 strlen(EFI_CALLING_EFI_APPLICATION),
                                 (u8 *)EFI_CALLING_EFI_APPLICATION);
        if (ret != EFI_SUCCESS)
                goto out;

        entry = (struct smbios_entry *)find_smbios_table();
        if (entry) {
                ret = tcg2_measure_smbios(dev, entry);
                if (ret != EFI_SUCCESS)
                        goto out;
        }

        ret = tcg2_measure_gpt_data(dev, handle);
        if (ret != EFI_SUCCESS)
                goto out;

        for (pcr_index = 0; pcr_index <= 7; pcr_index++) {
                ret = tcg2_measure_event(dev, pcr_index, EV_SEPARATOR,
                                         sizeof(event), (u8 *)&event);
                if (ret != EFI_SUCCESS)
                        goto out;
        }

        tcg2_efi_app_invoked = true;
out:
        return ret;
}

/**
 * efi_tcg2_measure_efi_app_exit() - measure efi app exit
 *
 * Return:      status code
 */
efi_status_t efi_tcg2_measure_efi_app_exit(void)
{
        efi_status_t ret;
        struct udevice *dev;

        if (!is_tcg2_protocol_installed())
                return EFI_SUCCESS;

        ret = platform_get_tpm2_device(&dev);
        if (ret != EFI_SUCCESS)
                return ret;

        ret = tcg2_measure_event(dev, 4, EV_EFI_ACTION,
                                 strlen(EFI_RETURNING_FROM_EFI_APPLICATION),
                                 (u8 *)EFI_RETURNING_FROM_EFI_APPLICATION);
        return ret;
}

/**
 * efi_tcg2_notify_exit_boot_services() - ExitBootService callback
 *
 * @event:      callback event
 * @context:    callback context
 */
static void EFIAPI
efi_tcg2_notify_exit_boot_services(struct efi_event *event, void *context)
{
        efi_status_t ret;
        struct udevice *dev;

        EFI_ENTRY("%p, %p", event, context);

        event_log.ebs_called = true;

        if (!is_tcg2_protocol_installed()) {
                ret = EFI_SUCCESS;
                goto out;
        }

        ret = platform_get_tpm2_device(&dev);
        if (ret != EFI_SUCCESS)
                goto out;

        ret = tcg2_measure_event(dev, 5, EV_EFI_ACTION,
                                 strlen(EFI_EXIT_BOOT_SERVICES_INVOCATION),
                                 (u8 *)EFI_EXIT_BOOT_SERVICES_INVOCATION);
        if (ret != EFI_SUCCESS)
                goto out;

        ret = tcg2_measure_event(dev, 5, EV_EFI_ACTION,
                                 strlen(EFI_EXIT_BOOT_SERVICES_SUCCEEDED),
                                 (u8 *)EFI_EXIT_BOOT_SERVICES_SUCCEEDED);

out:
        EFI_EXIT(ret);
}

/**
 * efi_tcg2_notify_exit_boot_services_failed()
 *  - notify ExitBootServices() is failed
 *
 * Return:      status code
 */
efi_status_t efi_tcg2_notify_exit_boot_services_failed(void)
{
        struct udevice *dev;
        efi_status_t ret;

        if (!is_tcg2_protocol_installed())
                return EFI_SUCCESS;

        ret = platform_get_tpm2_device(&dev);
        if (ret != EFI_SUCCESS)
                goto out;

        ret = tcg2_measure_event(dev, 5, EV_EFI_ACTION,
                                 strlen(EFI_EXIT_BOOT_SERVICES_INVOCATION),
                                 (u8 *)EFI_EXIT_BOOT_SERVICES_INVOCATION);
        if (ret != EFI_SUCCESS)
                goto out;

        ret = tcg2_measure_event(dev, 5, EV_EFI_ACTION,
                                 strlen(EFI_EXIT_BOOT_SERVICES_FAILED),
                                 (u8 *)EFI_EXIT_BOOT_SERVICES_FAILED);

out:
        return ret;
}

/**
 * tcg2_measure_secure_boot_variable() - measure secure boot variables
 *
 * @dev:        TPM device
 *
 * Return:      status code
 */
static efi_status_t tcg2_measure_secure_boot_variable(struct udevice *dev)
{
        u8 *data;
        efi_uintn_t data_size;
        u32 count, i;
        efi_status_t ret;
        u8 deployed_mode;
        efi_uintn_t size;
        u32 deployed_audit_pcr_index = 1;

        size = sizeof(deployed_mode);
        ret = efi_get_variable_int(u"DeployedMode", &efi_global_variable_guid,
                                   NULL, &size, &deployed_mode, NULL);
        if (ret != EFI_SUCCESS || !deployed_mode)
                deployed_audit_pcr_index = 7;

        count = ARRAY_SIZE(secure_variables);
        for (i = 0; i < count; i++) {
                const efi_guid_t *guid;

                guid = efi_auth_var_get_guid(secure_variables[i].name);

                data = efi_get_var(secure_variables[i].name, guid, &data_size);
                if (!data && !secure_variables[i].accept_empty)
                        continue;

                if (u16_strcmp(u"DeployedMode", secure_variables[i].name))
                        secure_variables[i].pcr_index = deployed_audit_pcr_index;
                if (u16_strcmp(u"AuditMode", secure_variables[i].name))
                        secure_variables[i].pcr_index = deployed_audit_pcr_index;

                ret = tcg2_measure_variable(dev, secure_variables[i].pcr_index,
                                            EV_EFI_VARIABLE_DRIVER_CONFIG,
                                            secure_variables[i].name, guid,
                                            data_size, data);
                free(data);
                if (ret != EFI_SUCCESS)
                        goto error;
        }

error:
        return ret;
}

/**
 * efi_tcg2_do_initial_measurement() - do initial measurement
 *
 * Return:      status code
 */
efi_status_t efi_tcg2_do_initial_measurement(void)
{
        efi_status_t ret;
        struct udevice *dev;

        if (!is_tcg2_protocol_installed())
                return EFI_SUCCESS;

        ret = platform_get_tpm2_device(&dev);
        if (ret != EFI_SUCCESS)
                return EFI_SECURITY_VIOLATION;

        ret = tcg2_measure_secure_boot_variable(dev);
        if (ret != EFI_SUCCESS)
                goto out;

out:
        return ret;
}

/**
 * efi_tcg2_register() - register EFI_TCG2_PROTOCOL
 *
 * If a TPM2 device is available, the TPM TCG2 Protocol is registered
 *
 * Return:      status code
 */
efi_status_t efi_tcg2_register(void)
{
        efi_status_t ret = EFI_SUCCESS;
        struct udevice *dev;
        struct efi_event *event;
        u32 err;

        ret = platform_get_tpm2_device(&dev);
        if (ret != EFI_SUCCESS) {
                log_warning("Unable to find TPMv2 device\n");
                return EFI_SUCCESS;
        }

        /* initialize the TPM as early as possible. */
        err = tpm_startup(dev, TPM_ST_CLEAR);
        if (err) {
                log_err("TPM startup failed\n");
                goto fail;
        }

        ret = efi_init_event_log();
        if (ret != EFI_SUCCESS) {
                tcg2_uninit();
                goto fail;
        }

        ret = efi_add_protocol(efi_root, &efi_guid_tcg2_protocol,
                               (void *)&efi_tcg2_protocol);
        if (ret != EFI_SUCCESS) {
                tcg2_uninit();
                goto fail;
        }

        ret = efi_create_event(EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_CALLBACK,
                               efi_tcg2_notify_exit_boot_services, NULL,
                               NULL, &event);
        if (ret != EFI_SUCCESS) {
                tcg2_uninit();
                goto fail;
        }

        return ret;

fail:
        log_err("Cannot install EFI_TCG2_PROTOCOL\n");
        return ret;
}