acpi: Add IORT helper functions

[coreboot2.git] / util / cbfstool / fit.c

/* Firmware Interface Table support */
/* SPDX-License-Identifier: GPL-2.0-only */

#include <inttypes.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "fit.h"

/* FIXME: This code assumes it is being executed on a little endian machine. */

#define FIT_POINTER_LOCATION 0xffffffc0
#define FIT_TABLE_LOWEST_ADDRESS ((uint32_t)(-(16 << 20)))
#define FIT_ENTRY_CHECKSUM_VALID 0x80
#define FIT_HEADER_VERSION 0x0100
#define FIT_HEADER_ADDRESS "_FIT_   "
#define FIT_MICROCODE_VERSION 0x0100
#define FIT_TXT_VERSION 0x0100

#define FIT_SIZE_ALIGNMENT 16

struct fit_entry {
        /**
         * Address is the base address of the firmware component
         * must be aligned on 16 byte boundary
         */
        uint64_t address;
        /**
         * Size is the span of the component in multiple of 16 bytes
         * Bits [24:31] are reserved and  must be set to 0
         */
        uint32_t size_reserved;
        /**
         * Component's version number in binary coded decimal (BCD) format.
         * For the FIT header entry, the value in this field will indicate the
         * revision number of the FIT data structure. The upper byte of the
         * revision field indicates the major revision and the lower byte
         * indicates the minor revision.
         */
        uint16_t version;
        /**
         * FIT types 0x00 to 0x7F
         * Bit 7 (C_V) indicates whether component has valid checksum.
         */
        uint8_t  type_checksum_valid;
        /**
         * Component's checksum. The modulo sum of all the bytes in the
         * component and the value in this field (Chksum) must add up to zero.
         * This field is only valid if the C_V flag is non-zero.
         */
        uint8_t  checksum;
} __packed;

struct fit_table {
        struct fit_entry header;
        struct fit_entry entries[];
} __packed;

struct microcode_header {
        uint32_t version;
        uint32_t revision;
        uint32_t date;
        uint32_t processor_signature;
        uint32_t checksum;
        uint32_t loader_revision;
        uint32_t processor_flags;
        uint32_t data_size;
        uint32_t total_size;
        uint8_t  reserved[12];
} __packed;

struct microcode_entry {
        int offset;
        int size;
};

static inline void *rom_buffer_pointer(struct buffer *buffer, int offset)
{
        return &buffer->data[offset];
}

static inline size_t fit_entry_size_bytes(const struct fit_entry *entry)
{
        return (entry->size_reserved & 0xffffff) << 4;
}

static inline void fit_entry_update_size(struct fit_entry *entry,
                                         const int size_bytes)
{
        /* Size is multiples of 16 bytes. */
        entry->size_reserved = (size_bytes >> 4) & 0xffffff;
}

static inline void fit_entry_add_size(struct fit_entry *entry,
                                      const int size_bytes)
{
        int size = fit_entry_size_bytes(entry);
        size += size_bytes;
        fit_entry_update_size(entry, size);
}

static inline int fit_entry_type(struct fit_entry *entry)
{
        return entry->type_checksum_valid & ~FIT_ENTRY_CHECKSUM_VALID;
}

/*
 * Get an offset from a host pointer. This function assumes the ROM is located
 * in the host address space at [4G - romsize -> 4G). It also assume all
 * pointers have values within this address range.
 */
static inline int ptr_to_offset(fit_offset_converter_t helper,
                                const struct buffer *region, uint32_t host_ptr)
{
        return helper(region, -host_ptr);
}

/*
 * Get a pointer from an offset. This function assumes the ROM is located
 * in the host address space at [4G - romsize -> 4G). It also assume all
 * pointers have values within this address range.
 */
static inline uint32_t offset_to_ptr(fit_offset_converter_t helper,
                                     const struct buffer *region, int offset)
{
        return -helper(region, offset);
}

/*
 * Return the number of FIT entries.
 */
static inline size_t fit_table_entries(const struct fit_table *fit)
{
        if (!fit)
                return 0;

        return (fit_entry_size_bytes(&fit->header) / FIT_SIZE_ALIGNMENT) - 1;
}

/*
 * Return the number of unused entries.
 */
static inline size_t fit_free_space(struct fit_table *fit,
                                 const size_t max_entries)
{
        if (!fit)
                return 0;

        return max_entries - fit_table_entries(fit);
}

/*
 * Sort entries by type and fill gaps (entries with type unused).
 * To be called after adding or deleting entries.
 *
 * This one is critical, as mentioned in Chapter 1.2.1 "FIT Ordering Rules"
 * "Firmware Interface Table BIOS Specification".
 *
 * We need to use a stable sorting algorithm, as the order of
 * FIT_TYPE_BIOS_STARTUP matter for measurements.
 */
static void sort_fit_table(struct fit_table *fit)
{
        struct fit_entry tmp;
        size_t i, j;
        int swapped;

        /* Bubble sort entries */
        for (j = 0; j < fit_table_entries(fit) - 1; j++) {
                swapped = 0;
                for (i = 0; i < fit_table_entries(fit) - j - 1; i++) {
                        if (fit->entries[i].type_checksum_valid <=
                            fit->entries[i + 1].type_checksum_valid)
                                continue;
                        /* SWAP entries */
                        memcpy(&tmp, &fit->entries[i], sizeof(tmp));
                        memcpy(&fit->entries[i], &fit->entries[i + 1],
                               sizeof(fit->entries[i]));
                        memcpy(&fit->entries[i + 1], &tmp,
                               sizeof(fit->entries[i + 1]));
                        swapped = 1;
                }
                if (!swapped)
                        break;
        }
}

static int fit_table_verified(struct fit_table *table)
{
        if (!table)
                return 0;

        /* Check that the address field has the proper signature. */
        if (strncmp((const char *)&table->header.address, FIT_HEADER_ADDRESS,
                        sizeof(table->header.address)))
                return 0;

        if (table->header.version != FIT_HEADER_VERSION)
                return 0;

        if (fit_entry_type(&table->header) != FIT_TYPE_HEADER)
                return 0;

        /* Assume that the FIT table contains at least the header */
        if (fit_entry_size_bytes(&table->header) < sizeof(struct fit_entry))
                return 0;

        return 1;
}

/*
 * Update the FIT checksum.
 * To be called after modifiying the table.
 */
static void update_fit_checksum(struct fit_table *fit)
{
        int size_bytes;
        uint8_t *buffer;
        uint8_t result;
        int i;

        if (!fit)
                return;

        fit->header.checksum = 0;
        size_bytes = fit_entry_size_bytes(&fit->header);
        result = 0;
        buffer = (void *)fit;
        for (i = 0; i < size_bytes; i++)
                result += buffer[i];
        fit->header.checksum = -result;
}

/*
 * Return a pointer to the next free entry.
 * Caller must take care if enough space is available.
 */
static struct fit_entry *get_next_free_entry(struct fit_table *fit)
{
        return &fit->entries[fit_table_entries(fit)];
}

static void fit_location_from_cbfs_header(uint32_t *current_offset,
                                          uint32_t *file_length, void *ptr)
{
        struct buffer buf;
        struct cbfs_file header;
        memset(&buf, 0, sizeof(buf));

        buf.data = ptr;
        buf.size = sizeof(header);

        bgets(&buf, header.magic, sizeof(header.magic));
        header.len = xdr_be.get32(&buf);
        header.type = xdr_be.get32(&buf);
        header.attributes_offset = xdr_be.get32(&buf);
        header.offset = xdr_be.get32(&buf);

        *current_offset = header.offset;
        *file_length = header.len;
}

static int
parse_microcode_blob(struct cbfs_image *image,
                     const char *blob_name,
                     size_t *mcus_found,
                     struct microcode_entry *mcus,
                     const size_t max_fit_entries)
{
        size_t num_mcus;
        uint32_t current_offset;
        uint32_t file_length;
        struct cbfs_file *mcode_file;

        mcode_file = cbfs_get_entry(image, blob_name);
        if (!mcode_file) {
                ERROR("Couldn't find microcode blob.\n");
                return 1;
        }

        fit_location_from_cbfs_header(&current_offset, &file_length,
                                      mcode_file);
        current_offset += cbfs_get_entry_addr(image, mcode_file);

        num_mcus = 0;
        while (file_length > sizeof(struct microcode_header)) {
                const struct microcode_header *mcu_header;

                mcu_header = rom_buffer_pointer(&image->buffer, current_offset);
                if (!mcu_header) {
                        ERROR("Couldn't parse microcode header.\n");
                        return 1;
                }

                /* Newer microcode updates include a size field, whereas older
                 * containers set it at 0 and are exactly 2048 bytes long */
                uint32_t total_size = mcu_header->total_size ?: 2048;

                /* Quickly sanity check a prospective microcode update. */
                if (total_size < sizeof(*mcu_header) ||
                    total_size > file_length)
                        break;

                if (num_mcus == max_fit_entries) {
                        ERROR("Maximum of FIT entries reached.\n");
                        return 1;
                }

                /* FIXME: Should the checksum be validated? */
                mcus[num_mcus].offset = current_offset;
                mcus[num_mcus].size = total_size;

                /* Proceed to next payload. */
                current_offset += mcus[num_mcus].size;
                file_length -= mcus[num_mcus].size;
                num_mcus++;
                if (file_length < sizeof(struct microcode_header))
                        break;
        }

        /* Update how many microcode updates we found. */
        *mcus_found = num_mcus;

        return 0;
}

/* There can be zero or more FIT_TYPE_MICROCODE entries */
static void update_fit_ucode_entry(struct fit_table *fit,
                                   struct fit_entry *entry,
                                   const uint64_t mcu_addr)
{
        entry->address = mcu_addr;
        /*
         * While loading MCU, its size is not referred from FIT and
         * rather from the MCU header, hence we can assign zero here.
         */
        entry->size_reserved = 0;
        entry->type_checksum_valid = FIT_TYPE_MICROCODE;
        entry->version = FIT_MICROCODE_VERSION;
        entry->checksum = 0;
        fit_entry_add_size(&fit->header, sizeof(struct fit_entry));
}

/*
 * There can be zero or one FIT_TYPE_BIOS_ACM entry per table.
 * In case there's a FIT_TYPE_BIOS_ACM entry, at least one
 * FIT_TYPE_BIOS_STARTUP entry must exist.
 *
 * The caller has to provide valid arguments as those aren't verfied.
 */
static void update_fit_bios_acm_entry(struct fit_table *fit,
                                      struct fit_entry *entry,
                                      const uint64_t acm_addr)
{
        entry->address = acm_addr;
        /*
         * The Address field points to a BIOS ACM. The Address field points to
         * the first byte of the AC module header. When BIOS ACM is loaded in
         * Authenticated Code RAM, one MTRR base/limit pair is used to map it.
         */
        entry->size_reserved = 0;
        entry->type_checksum_valid = FIT_TYPE_BIOS_ACM;
        entry->version = FIT_TXT_VERSION;
        entry->checksum = 0;
        fit_entry_add_size(&fit->header, sizeof(struct fit_entry));
}

/*
 * In case there's a FIT_TYPE_BIOS_ACM entry, at least one
 * FIT_TYPE_BIOS_STARTUP entry must exist.
 *
 * The caller has to provide valid arguments as those aren't verfied.
 */
static void update_fit_bios_startup_entry(struct fit_table *fit,
                                          struct fit_entry *entry,
                                          const uint64_t sm_addr,
                                          const uint32_t sm_size)
{
        entry->address = sm_addr;
        assert(sm_size % 16 == 0);
        /*
         * BIOS Startup code is defined as the code that gets control at the
         * reset vector and continues the chain of trust in TCG-compliant
         * fashion. In addition, this code may also configure memory and SMRAM.
         */
        fit_entry_update_size(entry, sm_size);
        entry->type_checksum_valid = FIT_TYPE_BIOS_STARTUP;
        entry->version = FIT_TXT_VERSION;
        entry->checksum = 0;
        fit_entry_add_size(&fit->header, sizeof(struct fit_entry));
}

/*
 * There can be zero or one FIT_TYPE_BIOS_POLICY Record in the FIT.
 * If the platform uses the hash comparison method and employs a
 * failsafe bootblock, one FIT_TYPE_BIOS_POLICY entry is needed to
 * contain the failsafe hash.
 * If the platform uses the Signature verification method, one
 * FIT_TYPE_BIOS_POLICY entry is needed. In this case, the entry
 * contains the OEM key, hash of the BIOS and signature over the hash
 * using the OEM key.
 * In all other cases, the FIT_TYPE_BIOS_POLICY record is not required.
 *
 * The caller has to provide valid arguments as those aren't verfied.
 */
static void update_fit_bios_policy_entry(struct fit_table *fit,
                                         struct fit_entry *entry,
                                         const uint64_t lcp_policy_addr,
                                         const uint32_t lcp_policy_size)
{
        entry->address = lcp_policy_addr;
        fit_entry_update_size(entry, lcp_policy_size);
        entry->type_checksum_valid = FIT_TYPE_BIOS_POLICY;
        entry->version = FIT_TXT_VERSION;
        entry->checksum = 0;
        fit_entry_add_size(&fit->header, sizeof(struct fit_entry));
}

/*
 * There can be zero or one FIT_TYPE_TXT_POLICY entries
 *
 * The caller has to provide valid arguments as those aren't verfied.
 */
static void update_fit_txt_policy_entry(struct fit_table *fit,
                                        struct fit_entry *entry,
                                        uint64_t txt_policy_addr)
{
        entry->address = txt_policy_addr;
        /*
         * Points to the flag indicating if TXT is enabled on this platform.
         * If not present, TXT is not disabled by FIT.
         */
        entry->size_reserved = 0;
        entry->type_checksum_valid = FIT_TYPE_TXT_POLICY;
        entry->version = 0x1;
        entry->checksum = 0;
        fit_entry_add_size(&fit->header, sizeof(struct fit_entry));
}

/*
 * There can be zero or one FIT_TYPE_BOOT_POLICY entries
 *
 * The caller has to provide valid arguments as those aren't verified.
 */
static void update_fit_boot_policy_entry(struct fit_table *fit,
                                        struct fit_entry *entry,
                                        uint64_t boot_policy_addr,
                                        uint32_t boot_policy_size)
{
        entry->address = boot_policy_addr;
        entry->type_checksum_valid = FIT_TYPE_BOOT_POLICY;
        entry->size_reserved = boot_policy_size;
        entry->version = FIT_TXT_VERSION;
        entry->checksum = 0;
        fit_entry_add_size(&fit->header, sizeof(struct fit_entry));
}

/*
 * There can be zero or one FIT_TYPE_KEY_MANIFEST entries
 *
 * The caller has to provide valid arguments as those aren't verified.
 */
static void update_fit_key_manifest_entry(struct fit_table *fit,
                                        struct fit_entry *entry,
                                        uint64_t key_manifest_addr,
                                        uint32_t key_manifest_size)
{
        entry->address = key_manifest_addr;

        entry->type_checksum_valid = FIT_TYPE_KEY_MANIFEST;
        entry->size_reserved = key_manifest_size;
        entry->version = FIT_TXT_VERSION;
        entry->checksum = 0;
        fit_entry_add_size(&fit->header, sizeof(struct fit_entry));
}

/* Special case for ucode CBFS file, as it might contain more than one ucode */
int fit_add_microcode_file(struct fit_table *fit,
                           struct cbfs_image *image,
                           const char *blob_name,
                           fit_offset_converter_t offset_helper,
                           const size_t max_fit_entries)
{
        struct microcode_entry *mcus;

        size_t i;
        size_t mcus_found;

        mcus = malloc(sizeof(*mcus) * max_fit_entries);
        if (!mcus) {
                ERROR("Couldn't allocate memory for microcode entries.\n");
                return 1;
        }

        if (parse_microcode_blob(image, blob_name, &mcus_found, mcus,
                                 max_fit_entries)) {
                free(mcus);
                return 1;
        }

        for (i = 0; i < mcus_found; i++) {
                if (fit_add_entry(fit,
                                  offset_to_ptr(offset_helper, &image->buffer,
                                                mcus[i].offset),
                                  0,
                                  FIT_TYPE_MICROCODE,
                                  max_fit_entries)) {

                        free(mcus);
                        return 1;
                }
        }

        free(mcus);
        return 0;
}

static uint32_t *get_fit_ptr(struct buffer *bootblock, fit_offset_converter_t offset_fn,
                      uint32_t topswap_size)
{
        return rom_buffer_pointer(bootblock,
                                  ptr_to_offset(offset_fn, bootblock,
                                                FIT_POINTER_LOCATION - topswap_size));
}

/* Set the FIT pointer to a FIT table. */
int set_fit_pointer(struct buffer *bootblock,
                    const uint32_t fit_address,
                    fit_offset_converter_t offset_fn,
                    uint32_t topswap_size)
{
        struct fit_table *fit;
        uint32_t *fit_pointer = get_fit_ptr(bootblock, offset_fn, topswap_size);

        fit = rom_buffer_pointer(bootblock, ptr_to_offset(offset_fn, bootblock, fit_address));

        if (fit_address < FIT_TABLE_LOWEST_ADDRESS) {
                ERROR("FIT must be reside in the top 16MiB.\n");
                return 1;
        }

        if (!fit_table_verified(fit)) {
                ERROR("FIT not found at address.\n");
                return 1;
        }

        fit_pointer[0] = fit_address;
        fit_pointer[1] = 0;
        return 0;
}

/*
 * Return a pointer to the active FIT.
 */
struct fit_table *fit_get_table(struct buffer *bootblock,
                                fit_offset_converter_t offset_fn,
                                uint32_t topswap_size)
{
        struct fit_table *fit;
        uint32_t *fit_pointer = get_fit_ptr(bootblock, offset_fn, topswap_size);

        /* Ensure pointer is below 4GiB and within 16MiB of 4GiB */
        if (fit_pointer[1] != 0 || fit_pointer[0] < FIT_TABLE_LOWEST_ADDRESS) {
                ERROR("FIT not found.\n");
                return NULL;
        }

        fit = rom_buffer_pointer(bootblock,
                           ptr_to_offset(offset_fn, bootblock, *fit_pointer));
        if (!fit_table_verified(fit)) {
                ERROR("FIT not found.\n");
                return NULL;
        }

        return fit;
}

/*
 * Dump the current FIT in human readable format to stdout.
 */
int fit_dump(struct fit_table *fit)
{
        size_t i;

        if (!fit)
                return 1;

        printf("\n");
        printf("    FIT table:\n");

        if (fit_table_entries(fit) < 1) {
                printf("    empty\n\n");
                return 0;
        }

        printf("    %-6s %-20s %-16s %-8s\n", "Index", "Type", "Addr", "Size");

        for (i = 0; i < fit_table_entries(fit); i++) {
                const char *name;

                switch (fit->entries[i].type_checksum_valid) {
                case FIT_TYPE_MICROCODE:
                        name = "Microcode";
                        break;
                case FIT_TYPE_BIOS_ACM:
                        name = "BIOS ACM";
                        break;
                case FIT_TYPE_BIOS_STARTUP:
                        name = "BIOS Startup Module";
                        break;
                case FIT_TYPE_TPM_POLICY:
                        name = "TPM Policy";
                        break;
                case FIT_TYPE_BIOS_POLICY:
                        name = "BIOS Policy";
                        break;
                case FIT_TYPE_TXT_POLICY:
                        name = "TXT Policy";
                        break;
                case FIT_TYPE_KEY_MANIFEST:
                        name = "Key Manifest";
                        break;
                case FIT_TYPE_BOOT_POLICY:
                        name = "Boot Policy";
                        break;
                case FIT_TYPE_CSE_SECURE_BOOT:
                        name = "CSE SecureBoot";
                        break;
                case FIT_TYPE_TXTSX_POLICY:
                        name = "TXTSX policy";
                        break;
                case FIT_TYPE_JMP_DEBUG_POLICY:
                        name = "JMP debug policy";
                        break;
                case FIT_TYPE_UNUSED:
                        name = "unused";
                        break;
                default:
                        name = "unknown";
                }

                printf("    %6zd %-20s 0x%08"PRIx64"      0x%08zx\n", i, name,
                        fit->entries[i].address,
                        fit_entry_size_bytes(&fit->entries[i]));
        }
        printf("\n");
        return 0;
}

/*
 * Remove all entries from table.
 */
int fit_clear_table(struct fit_table *fit)
{
        if (!fit)
                return 1;

        memset(fit->entries, 0,
               sizeof(struct fit_entry) * fit_table_entries(fit));

        /* Reset entry counter in header */
        fit_entry_update_size(&fit->header, sizeof(fit->header));

        update_fit_checksum(fit);

        return 0;
}

/*
 * Returns true if the FIT type is know and can be added to the table.
 */
int fit_is_supported_type(const enum fit_type type)
{
        switch (type) {
        case FIT_TYPE_MICROCODE:
        case FIT_TYPE_BIOS_ACM:
        case FIT_TYPE_BIOS_STARTUP:
        case FIT_TYPE_BIOS_POLICY:
        case FIT_TYPE_TXT_POLICY:
        case FIT_TYPE_KEY_MANIFEST:
        case FIT_TYPE_BOOT_POLICY:
                return 1;
        case FIT_TYPE_TPM_POLICY:
        default:
                return 0;
        }
}

/*
 * Adds an known entry to the FIT.
 * len is optional for same types and might be zero.
 * offset is an absolute address in 32-bit protected mode address space.
 */
int fit_add_entry(struct fit_table *fit,
                  const uint32_t offset,
                  const uint32_t len,
                  const enum fit_type type,
                  const size_t max_fit_entries)
{
        struct fit_entry *entry;

        if (!fit) {
                ERROR("Internal error.");
                return 1;
        }

        if (fit_free_space(fit, max_fit_entries) < 1) {
                ERROR("No space left in FIT.");
                return 1;
        }

        if (!fit_is_supported_type(type)) {
                ERROR("Unsupported FIT type %u\n", type);
                return 1;
        }

        DEBUG("Adding new entry type %u at offset %zd\n", type,
              fit_table_entries(fit));

        entry = get_next_free_entry(fit);

        switch (type) {
        case FIT_TYPE_MICROCODE:
                update_fit_ucode_entry(fit, entry, offset);
                break;
        case FIT_TYPE_BIOS_ACM:
                update_fit_bios_acm_entry(fit, entry, offset);
                break;
        case FIT_TYPE_BIOS_STARTUP:
                update_fit_bios_startup_entry(fit, entry, offset, len);
                break;
        case FIT_TYPE_BIOS_POLICY:
                update_fit_bios_policy_entry(fit, entry, offset, len);
                break;
        case FIT_TYPE_TXT_POLICY:
                update_fit_txt_policy_entry(fit, entry, offset);
                break;
        case FIT_TYPE_KEY_MANIFEST:
                update_fit_key_manifest_entry(fit, entry, offset, len);
                break;
        case FIT_TYPE_BOOT_POLICY:
                update_fit_boot_policy_entry(fit, entry, offset, len);
                break;
        default:
                return 1;
        }

        sort_fit_table(fit);

        update_fit_checksum(fit);

        return 0;
}

/*
 * Delete one entry from table.
 */
int fit_delete_entry(struct fit_table *fit,
                     const size_t idx)
{
        if (!fit) {
                ERROR("Internal error.");
                return 1;
        }

        if (idx >= fit_table_entries(fit)) {
                ERROR("Index out of range.");
                return 1;
        }

        memset(&fit->entries[idx], 0, sizeof(struct fit_entry));

        fit->entries[idx].type_checksum_valid = FIT_TYPE_UNUSED;

        sort_fit_table(fit);

        /* The unused entry is now the last one */
        fit_entry_add_size(&fit->header, -(int)sizeof(struct fit_entry));

        update_fit_checksum(fit);

        return 0;
}