Documentation/releases: Add 4.15 release notes template

[coreboot.git] / src / commonlib / fsp_relocate.c

/* SPDX-License-Identifier: GPL-2.0-only */

#include <console/console.h>
#include <commonlib/endian.h>
#include <commonlib/fsp.h>
/*
 * Intel's code does not have a handle on changing global packing state.
 * Therefore, one needs to protect against packing policies that are set
 * globally for a compilation unit just by including a header file.
 */
#pragma pack(push)

/* Default bind FSP 1.1 API to edk2 UEFI 2.4 types. */
#include <vendorcode/intel/edk2/uefi_2.4/uefi_types.h>
#include <vendorcode/intel/fsp/fsp1_1/IntelFspPkg/Include/FspInfoHeader.h>

/* Restore original packing policy. */
#pragma pack(pop)

#include <commonlib/helpers.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>

#define FSP_DBG_LVL BIOS_NEVER

/*
 * UEFI defines everything as little endian. However, this piece of code
 * can be integrated in a userland tool. That tool could be on a big endian
 * machine so one needs to access the fields within UEFI structures using
 * endian-aware accesses.
 */

/* Return 0 if equal. Non-zero if not equal. */
static int guid_compare(const EFI_GUID *le_guid, const EFI_GUID *native_guid)
{
        if (read_le32(&le_guid->Data1) != native_guid->Data1)
                return 1;
        if (read_le16(&le_guid->Data2) != native_guid->Data2)
                return 1;
        if (read_le16(&le_guid->Data3) != native_guid->Data3)
                return 1;
        return memcmp(le_guid->Data4, native_guid->Data4,
                        ARRAY_SIZE(le_guid->Data4));
}

static const EFI_GUID ffs2_guid = EFI_FIRMWARE_FILE_SYSTEM2_GUID;
static const EFI_GUID fih_guid = FSP_INFO_HEADER_GUID;

struct fsp_patch_table {
        uint32_t signature;
        uint16_t header_length;
        uint8_t header_revision;
        uint8_t reserved;
        uint32_t patch_entry_num;
        uint32_t patch_entries[0];
} __packed;

#define FSPP_SIG 0x50505346

static void *relative_offset(void *base, ssize_t offset)
{
        uintptr_t loc;

        loc = (uintptr_t)base;
        loc += offset;

        return (void *)loc;
}

static uint32_t *fspp_reloc(void *fsp, size_t fsp_size, uint32_t e)
{
        size_t offset;

        /* Offsets live in bits 23:0. */
        offset = e & 0xffffff;

        /* If bit 31 is set then the offset is considered a negative value
         * relative to the end of the image using 16MiB as the offset's
         * reference. */
        if (e & (1 << 31))
                offset = fsp_size - (16 * MiB - offset);

        /* Determine if offset falls within fsp_size for a 32 bit relocation. */
        if (offset > fsp_size - sizeof(uint32_t))
                return NULL;

        return relative_offset(fsp, offset);
}

static int reloc_type(uint16_t reloc_entry)
{
        /* Reloc type in upper 4 bits */
        return reloc_entry >> 12;
}

static size_t reloc_offset(uint16_t reloc_entry)
{
        /* Offsets are in low 12 bits. */
        return reloc_entry & ((1 << 12) - 1);
}

static int te_relocate(uintptr_t new_addr, void *te)
{
        EFI_TE_IMAGE_HEADER *teih;
        EFI_IMAGE_DATA_DIRECTORY *relocd;
        EFI_IMAGE_BASE_RELOCATION *relocb;
        uintptr_t image_base;
        size_t fixup_offset;
        size_t num_relocs;
        uint16_t *reloc;
        size_t relocd_offset;
        uint8_t *te_base;
        uint32_t adj;

        teih = te;

        if (read_le16(&teih->Signature) != EFI_TE_IMAGE_HEADER_SIGNATURE) {
                printk(BIOS_ERR, "TE Signature mismatch: %x vs %x\n",
                        read_le16(&teih->Signature),
                        EFI_TE_IMAGE_HEADER_SIGNATURE);
                return -1;
        }

        /*
         * A TE image is created by converting a PE file. Because of this
         * the offsets within the headers are off. In order to calculate
         * the correct relative offsets one needs to subtract fixup_offset
         * from the encoded offsets. Similarly, the linked address of the
         * program is found by adding the fixup_offset to the ImageBase.
         */
        fixup_offset = read_le16(&teih->StrippedSize);
        fixup_offset -= sizeof(EFI_TE_IMAGE_HEADER);
        /* Keep track of a base that is correctly adjusted so that offsets
         * can be used directly. */
        te_base = te;
        te_base -= fixup_offset;

        image_base = read_le64(&teih->ImageBase);
        adj = new_addr - (image_base + fixup_offset);

        printk(FSP_DBG_LVL, "TE Image %p -> %p adjust value: %x\n",
                (void *)image_base, (void *)new_addr, adj);

        /* Adjust ImageBase for consistency. */
        write_le64(&teih->ImageBase, (uint32_t)(image_base + adj));

        relocd = &teih->DataDirectory[EFI_TE_IMAGE_DIRECTORY_ENTRY_BASERELOC];

        relocd_offset = 0;
        /* Though the field name is VirtualAddress it's actually relative to
         * the beginning of the image which is linked at ImageBase. */
        relocb = relative_offset(te,
                        read_le32(&relocd->VirtualAddress) - fixup_offset);
        while (relocd_offset < read_le32(&relocd->Size)) {
                size_t rva_offset = read_le32(&relocb->VirtualAddress);

                printk(FSP_DBG_LVL, "Relocs for RVA offset %zx\n", rva_offset);
                num_relocs = read_le32(&relocb->SizeOfBlock) - sizeof(*relocb);
                num_relocs /= sizeof(uint16_t);
                reloc = relative_offset(relocb, sizeof(*relocb));

                printk(FSP_DBG_LVL, "Num relocs in block: %zx\n", num_relocs);

                while (num_relocs > 0) {
                        uint16_t reloc_val = read_le16(reloc);
                        int type = reloc_type(reloc_val);
                        size_t offset = reloc_offset(reloc_val);

                        printk(FSP_DBG_LVL, "reloc type %x offset %zx\n",
                                type, offset);

                        if (type == EFI_IMAGE_REL_BASED_HIGHLOW) {
                                uint32_t *reloc_addr;
                                uint32_t val;

                                offset += rva_offset;
                                reloc_addr = (void *)&te_base[offset];
                                val = read_le32(reloc_addr);

                                printk(FSP_DBG_LVL, "Adjusting %p %x -> %x\n",
                                        reloc_addr, val, val + adj);
                                write_le32(reloc_addr, val + adj);
                        } else if (type != EFI_IMAGE_REL_BASED_ABSOLUTE) {
                                printk(BIOS_ERR, "Unknown reloc type: %x\n",
                                        type);
                                return -1;
                        }
                        num_relocs--;
                        reloc++;
                }

                /* Track consumption of relocation directory contents. */
                relocd_offset += read_le32(&relocb->SizeOfBlock);
                /* Get next relocation block to process. */
                relocb = relative_offset(relocb,
                                        read_le32(&relocb->SizeOfBlock));
        }

        return 0;
}

static size_t csh_size(const EFI_COMMON_SECTION_HEADER *csh)
{
        size_t size;

        /* Unpack the array into a type that can be used. */
        size = 0;
        size |= read_le8(&csh->Size[0]) << 0;
        size |= read_le8(&csh->Size[1]) << 8;
        size |= read_le8(&csh->Size[2]) << 16;

        return size;
}

static size_t section_data_offset(const EFI_COMMON_SECTION_HEADER *csh)
{
        if (csh_size(csh) == 0x00ffffff)
                return sizeof(EFI_COMMON_SECTION_HEADER2);
        else
                return sizeof(EFI_COMMON_SECTION_HEADER);
}

static size_t section_data_size(const EFI_COMMON_SECTION_HEADER *csh)
{
        size_t section_size;

        if (csh_size(csh) == 0x00ffffff)
                section_size = read_le32(&SECTION2_SIZE(csh));
        else
                section_size = csh_size(csh);

        return section_size - section_data_offset(csh);
}

static size_t file_section_offset(const EFI_FFS_FILE_HEADER *ffsfh)
{
        if (IS_FFS_FILE2(ffsfh))
                return sizeof(EFI_FFS_FILE_HEADER2);
        else
                return sizeof(EFI_FFS_FILE_HEADER);
}

static size_t ffs_file_size(const EFI_FFS_FILE_HEADER *ffsfh)
{
        size_t size;

        if (IS_FFS_FILE2(ffsfh)) {
                /*
                 * this cast is needed with UEFI 2.6 headers in order
                 * to read the UINT32 value that FFS_FILE2_SIZE converts
                 * the return into
                 */
                uint32_t file2_size = FFS_FILE2_SIZE(ffsfh);
                size = read_le32(&file2_size);
        } else {
                size = read_le8(&ffsfh->Size[0]) << 0;
                size |= read_le8(&ffsfh->Size[1]) << 8;
                size |= read_le8(&ffsfh->Size[2]) << 16;
        }
        return size;
}

static int relocate_patch_table(void *fsp, size_t size, size_t offset,
                                ssize_t adjustment)
{
        struct fsp_patch_table *table;
        size_t num;
        size_t num_entries;

        table = relative_offset(fsp, offset);

        if ((offset + sizeof(*table) > size) ||
            (read_le16(&table->header_length) + offset) > size) {
                printk(BIOS_ERR, "FSPP not entirely contained in region.\n");
                return -1;
        }

        num_entries = read_le32(&table->patch_entry_num);
        printk(FSP_DBG_LVL, "FSPP relocs: %zx\n", num_entries);

        for (num = 0; num < num_entries; num++) {
                uint32_t *reloc;
                uint32_t reloc_val;

                reloc = fspp_reloc(fsp, size,
                                read_le32(&table->patch_entries[num]));

                if (reloc == NULL) {
                        printk(BIOS_ERR, "Ignoring FSPP entry: %x\n",
                                read_le32(&table->patch_entries[num]));
                        continue;
                }

                reloc_val = read_le32(reloc);
                printk(FSP_DBG_LVL, "Adjusting %p %x -> %x\n",
                        reloc, reloc_val,
                        (unsigned int)(reloc_val + adjustment));

                write_le32(reloc, reloc_val + adjustment);
        }

        return 0;
}

static ssize_t relocate_remaining_items(void *fsp, size_t size,
                                        uintptr_t new_addr, size_t fih_offset)
{
        EFI_FFS_FILE_HEADER *ffsfh;
        EFI_COMMON_SECTION_HEADER *csh;
        FSP_INFO_HEADER *fih;
        ssize_t adjustment;
        size_t offset;

        printk(FSP_DBG_LVL, "FSP_INFO_HEADER offset is %zx\n", fih_offset);

        if (fih_offset == 0) {
                printk(BIOS_ERR, "FSP_INFO_HEADER offset is 0.\n");
                return -1;
        }

        /* FSP_INFO_HEADER at first file in FV within first RAW section. */
        ffsfh = relative_offset(fsp, fih_offset);
        fih_offset += file_section_offset(ffsfh);
        csh = relative_offset(fsp, fih_offset);
        fih_offset += section_data_offset(csh);
        fih = relative_offset(fsp, fih_offset);

        if (guid_compare(&ffsfh->Name, &fih_guid)) {
                printk(BIOS_ERR, "Bad FIH GUID.\n");
                return -1;
        }

        if (read_le8(&csh->Type) != EFI_SECTION_RAW) {
                printk(BIOS_ERR, "FIH file should have raw section: %x\n",
                        read_le8(&csh->Type));
                return -1;
        }

        if (read_le32(&fih->Signature) != FSP_SIG) {
                printk(BIOS_ERR, "Unexpected FIH signature: %08x\n",
                        read_le32(&fih->Signature));
                return -1;
        }

        adjustment = (intptr_t)new_addr - read_le32(&fih->ImageBase);

        /* Update ImageBase to reflect FSP's new home. */
        write_le32(&fih->ImageBase, adjustment + read_le32(&fih->ImageBase));

        /* Need to find patch table and adjust each entry. The tables
         * following FSP_INFO_HEADER have a 32-bit signature and header
         * length. The patch table is denoted as having a 'FSPP' signature;
         * the table format doesn't follow the other tables. */
        offset = fih_offset + read_le32(&fih->HeaderLength);
        while (offset + 2 * sizeof(uint32_t) <= size) {
                uint32_t *table_headers;

                table_headers = relative_offset(fsp, offset);

                printk(FSP_DBG_LVL, "Checking offset %zx for 'FSPP'\n",
                        offset);

                if (read_le32(&table_headers[0]) != FSPP_SIG) {
                        offset += read_le32(&table_headers[1]);
                        continue;
                }

                if (relocate_patch_table(fsp, size, offset, adjustment)) {
                        printk(BIOS_ERR, "FSPP relocation failed.\n");
                        return -1;
                }

                return fih_offset;
        }

        printk(BIOS_ERR, "Could not find the FSP patch table.\n");
        return -1;
}

static ssize_t relocate_fvh(uintptr_t new_addr, void *fsp, size_t fsp_size,
                                size_t fvh_offset, size_t *fih_offset)
{
        EFI_FIRMWARE_VOLUME_HEADER *fvh;
        EFI_FFS_FILE_HEADER *ffsfh;
        EFI_COMMON_SECTION_HEADER *csh;
        size_t offset;
        size_t file_offset;
        size_t size;
        size_t fv_length;

        offset = fvh_offset;
        fvh = relative_offset(fsp, offset);

        if (read_le32(&fvh->Signature) != EFI_FVH_SIGNATURE)
                return -1;

        fv_length = read_le64(&fvh->FvLength);

        printk(FSP_DBG_LVL, "FVH length: %zx Offset: %zx Mapping length: %zx\n",
                fv_length, offset, fsp_size);

        if (fv_length + offset > fsp_size)
                return -1;

        /* Parse only this FV. However, the algorithm uses offsets into the
         * entire FSP region so make size include the starting offset. */
        size = fv_length + offset;

        if (guid_compare(&fvh->FileSystemGuid, &ffs2_guid)) {
                printk(BIOS_ERR, "FVH not an FFS2 type.\n");
                return -1;
        }

        if (read_le16(&fvh->ExtHeaderOffset) != 0) {
                EFI_FIRMWARE_VOLUME_EXT_HEADER *fveh;

                offset += read_le16(&fvh->ExtHeaderOffset);
                fveh = relative_offset(fsp, offset);
                printk(FSP_DBG_LVL, "Extended Header Offset: %zx Size: %zx\n",
                        (size_t)read_le16(&fvh->ExtHeaderOffset),
                        (size_t)read_le32(&fveh->ExtHeaderSize));
                offset += read_le32(&fveh->ExtHeaderSize);
                /* FFS files are 8 byte aligned after extended header. */
                offset = ALIGN_UP(offset, 8);
        } else {
                offset += read_le16(&fvh->HeaderLength);
        }

        file_offset = offset;
        while (file_offset + sizeof(*ffsfh) < size) {
                offset = file_offset;
                printk(FSP_DBG_LVL, "file offset: %zx\n", file_offset);

                /* First file and section should be FSP info header. */
                if (fih_offset != NULL && *fih_offset == 0)
                        *fih_offset = file_offset;

                ffsfh = relative_offset(fsp, file_offset);

                printk(FSP_DBG_LVL, "file type = %x\n", read_le8(&ffsfh->Type));
                printk(FSP_DBG_LVL, "file attribs = %x\n",
                        read_le8(&ffsfh->Attributes));

                /* Exit FV relocation when empty space found */
                if (read_le8(&ffsfh->Type) == EFI_FV_FILETYPE_FFS_MAX)
                        break;

                /* Next file on 8 byte alignment. */
                file_offset += ffs_file_size(ffsfh);
                file_offset = ALIGN_UP(file_offset, 8);

                /* Padding files have no section information. */
                if (read_le8(&ffsfh->Type) == EFI_FV_FILETYPE_FFS_PAD)
                        continue;

                offset += file_section_offset(ffsfh);

                while (offset + sizeof(*csh) < file_offset) {
                        size_t data_size;
                        size_t data_offset;

                        csh = relative_offset(fsp, offset);

                        printk(FSP_DBG_LVL, "section offset: %zx\n", offset);
                        printk(FSP_DBG_LVL, "section type: %x\n",
                                read_le8(&csh->Type));

                        data_size = section_data_size(csh);
                        data_offset = section_data_offset(csh);

                        if (data_size + data_offset + offset > file_offset) {
                                printk(BIOS_ERR, "Section exceeds FV size.\n");
                                return -1;
                        }

                        /*
                         * The entire FSP image can be thought of as one
                         * program with a single link address even though there
                         * are multiple TEs linked separately. The reason is
                         * that each TE is linked for XIP. So in order to
                         * relocate the TE properly we need to form the
                         * relocated address based on the TE offset within
                         * FSP proper.
                         */
                        if (read_le8(&csh->Type) == EFI_SECTION_TE) {
                                void *te;
                                size_t te_offset = offset + data_offset;
                                uintptr_t te_addr = new_addr + te_offset;

                                printk(FSP_DBG_LVL, "TE image at offset %zx\n",
                                        te_offset);
                                te = relative_offset(fsp, te_offset);
                                te_relocate(te_addr, te);
                        }

                        offset += data_size + data_offset;
                        /* Sections are aligned to 4 bytes. */
                        offset = ALIGN_UP(offset, 4);
                }
        }

        /* Return amount of buffer parsed: FV size. */
        return fv_length;
}

ssize_t fsp_component_relocate(uintptr_t new_addr, void *fsp, size_t size)
{
        size_t offset;
        size_t fih_offset;

        offset = 0;
        fih_offset = 0;
        while (offset < size) {
                ssize_t nparsed;

                /* Relocate each FV within the FSP region. The FSP_INFO_HEADER
                 * should only be located in the first FV. */
                if (offset == 0)
                        nparsed = relocate_fvh(new_addr, fsp, size, offset,
                                                &fih_offset);
                else
                        nparsed = relocate_fvh(new_addr, fsp, size, offset,
                                                NULL);

                /* FV should be larger than 0 or failed to parse. */
                if (nparsed <= 0) {
                        printk(BIOS_ERR, "FV @ offset %zx relocation failed\n",
                                offset);
                        return -1;
                }

                offset += nparsed;
        }

        return relocate_remaining_items(fsp, size, new_addr, fih_offset);
}

ssize_t fsp1_1_relocate(uintptr_t new_addr, void *fsp, size_t size)
{
        return fsp_component_relocate(new_addr, fsp, size);
}