u-boot/lib/efi_loader/efi_image_loader.c
Ilias Apalodimas ebdea88d57 efi_loader: Fix loaded image alignment
We are ignoring the alignment communicated via the PE/COFF header.
Starting 5.10 the Linux kernel will loudly complain about it. For more
details look at [1] (in linux kernel).

So add a function that can allocate aligned EFI memory and use it for our
relocated loaded image.

[1] c32ac11da3f83 ("efi/libstub: arm64: Double check image alignment at entry")

Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Tested-by: Vincent Stehlé <vincent.stehle@arm.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2021-10-21 03:46:04 +02:00

989 lines
27 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* EFI image loader
*
* based partly on wine code
*
* Copyright (c) 2016 Alexander Graf
*/
#define LOG_CATEGORY LOGC_EFI
#include <common.h>
#include <cpu_func.h>
#include <efi_loader.h>
#include <log.h>
#include <malloc.h>
#include <pe.h>
#include <sort.h>
#include <crypto/pkcs7_parser.h>
#include <linux/err.h>
const efi_guid_t efi_global_variable_guid = EFI_GLOBAL_VARIABLE_GUID;
const efi_guid_t efi_guid_device_path = EFI_DEVICE_PATH_PROTOCOL_GUID;
const efi_guid_t efi_guid_loaded_image = EFI_LOADED_IMAGE_PROTOCOL_GUID;
const efi_guid_t efi_guid_loaded_image_device_path =
EFI_LOADED_IMAGE_DEVICE_PATH_PROTOCOL_GUID;
const efi_guid_t efi_simple_file_system_protocol_guid =
EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID;
const efi_guid_t efi_file_info_guid = EFI_FILE_INFO_GUID;
static int machines[] = {
#if defined(__aarch64__)
IMAGE_FILE_MACHINE_ARM64,
#elif defined(__arm__)
IMAGE_FILE_MACHINE_ARM,
IMAGE_FILE_MACHINE_THUMB,
IMAGE_FILE_MACHINE_ARMNT,
#endif
#if defined(__x86_64__)
IMAGE_FILE_MACHINE_AMD64,
#elif defined(__i386__)
IMAGE_FILE_MACHINE_I386,
#endif
#if defined(__riscv) && (__riscv_xlen == 32)
IMAGE_FILE_MACHINE_RISCV32,
#endif
#if defined(__riscv) && (__riscv_xlen == 64)
IMAGE_FILE_MACHINE_RISCV64,
#endif
0 };
/**
* efi_print_image_info() - print information about a loaded image
*
* If the program counter is located within the image the offset to the base
* address is shown.
*
* @obj: EFI object
* @image: loaded image
* @pc: program counter (use NULL to suppress offset output)
* Return: status code
*/
static efi_status_t efi_print_image_info(struct efi_loaded_image_obj *obj,
struct efi_loaded_image *image,
void *pc)
{
printf("UEFI image");
printf(" [0x%p:0x%p]",
image->image_base, image->image_base + image->image_size - 1);
if (pc && pc >= image->image_base &&
pc < image->image_base + image->image_size)
printf(" pc=0x%zx", pc - image->image_base);
if (image->file_path)
printf(" '%pD'", image->file_path);
printf("\n");
return EFI_SUCCESS;
}
/**
* efi_print_image_infos() - print information about all loaded images
*
* @pc: program counter (use NULL to suppress offset output)
*/
void efi_print_image_infos(void *pc)
{
struct efi_object *efiobj;
struct efi_handler *handler;
list_for_each_entry(efiobj, &efi_obj_list, link) {
list_for_each_entry(handler, &efiobj->protocols, link) {
if (!guidcmp(handler->guid, &efi_guid_loaded_image)) {
efi_print_image_info(
(struct efi_loaded_image_obj *)efiobj,
handler->protocol_interface, pc);
}
}
}
}
/**
* efi_loader_relocate() - relocate UEFI binary
*
* @rel: pointer to the relocation table
* @rel_size: size of the relocation table in bytes
* @efi_reloc: actual load address of the image
* @pref_address: preferred load address of the image
* Return: status code
*/
static efi_status_t efi_loader_relocate(const IMAGE_BASE_RELOCATION *rel,
unsigned long rel_size, void *efi_reloc,
unsigned long pref_address)
{
unsigned long delta = (unsigned long)efi_reloc - pref_address;
const IMAGE_BASE_RELOCATION *end;
int i;
if (delta == 0)
return EFI_SUCCESS;
end = (const IMAGE_BASE_RELOCATION *)((const char *)rel + rel_size);
while (rel < end && rel->SizeOfBlock) {
const uint16_t *relocs = (const uint16_t *)(rel + 1);
i = (rel->SizeOfBlock - sizeof(*rel)) / sizeof(uint16_t);
while (i--) {
uint32_t offset = (uint32_t)(*relocs & 0xfff) +
rel->VirtualAddress;
int type = *relocs >> EFI_PAGE_SHIFT;
uint64_t *x64 = efi_reloc + offset;
uint32_t *x32 = efi_reloc + offset;
uint16_t *x16 = efi_reloc + offset;
switch (type) {
case IMAGE_REL_BASED_ABSOLUTE:
break;
case IMAGE_REL_BASED_HIGH:
*x16 += ((uint32_t)delta) >> 16;
break;
case IMAGE_REL_BASED_LOW:
*x16 += (uint16_t)delta;
break;
case IMAGE_REL_BASED_HIGHLOW:
*x32 += (uint32_t)delta;
break;
case IMAGE_REL_BASED_DIR64:
*x64 += (uint64_t)delta;
break;
#ifdef __riscv
case IMAGE_REL_BASED_RISCV_HI20:
*x32 = ((*x32 & 0xfffff000) + (uint32_t)delta) |
(*x32 & 0x00000fff);
break;
case IMAGE_REL_BASED_RISCV_LOW12I:
case IMAGE_REL_BASED_RISCV_LOW12S:
/* We know that we're 4k aligned */
if (delta & 0xfff) {
log_err("Unsupported reloc offset\n");
return EFI_LOAD_ERROR;
}
break;
#endif
default:
log_err("Unknown Relocation off %x type %x\n",
offset, type);
return EFI_LOAD_ERROR;
}
relocs++;
}
rel = (const IMAGE_BASE_RELOCATION *)relocs;
}
return EFI_SUCCESS;
}
void __weak invalidate_icache_all(void)
{
/* If the system doesn't support icache_all flush, cross our fingers */
}
/**
* efi_set_code_and_data_type() - determine the memory types to be used for code
* and data.
*
* @loaded_image_info: image descriptor
* @image_type: field Subsystem of the optional header for
* Windows specific field
*/
static void efi_set_code_and_data_type(
struct efi_loaded_image *loaded_image_info,
uint16_t image_type)
{
switch (image_type) {
case IMAGE_SUBSYSTEM_EFI_APPLICATION:
loaded_image_info->image_code_type = EFI_LOADER_CODE;
loaded_image_info->image_data_type = EFI_LOADER_DATA;
break;
case IMAGE_SUBSYSTEM_EFI_BOOT_SERVICE_DRIVER:
loaded_image_info->image_code_type = EFI_BOOT_SERVICES_CODE;
loaded_image_info->image_data_type = EFI_BOOT_SERVICES_DATA;
break;
case IMAGE_SUBSYSTEM_EFI_RUNTIME_DRIVER:
case IMAGE_SUBSYSTEM_EFI_ROM:
loaded_image_info->image_code_type = EFI_RUNTIME_SERVICES_CODE;
loaded_image_info->image_data_type = EFI_RUNTIME_SERVICES_DATA;
break;
default:
log_err("invalid image type: %u\n", image_type);
/* Let's assume it is an application */
loaded_image_info->image_code_type = EFI_LOADER_CODE;
loaded_image_info->image_data_type = EFI_LOADER_DATA;
break;
}
}
/**
* efi_image_region_add() - add an entry of region
* @regs: Pointer to array of regions
* @start: Start address of region (included)
* @end: End address of region (excluded)
* @nocheck: flag against overlapped regions
*
* Take one entry of region \[@start, @end\[ and insert it into the list.
*
* * If @nocheck is false, the list will be sorted ascending by address.
* Overlapping entries will not be allowed.
*
* * If @nocheck is true, the list will be sorted ascending by sequence
* of adding the entries. Overlapping is allowed.
*
* Return: status code
*/
efi_status_t efi_image_region_add(struct efi_image_regions *regs,
const void *start, const void *end,
int nocheck)
{
struct image_region *reg;
int i, j;
if (regs->num >= regs->max) {
EFI_PRINT("%s: no more room for regions\n", __func__);
return EFI_OUT_OF_RESOURCES;
}
if (end < start)
return EFI_INVALID_PARAMETER;
for (i = 0; i < regs->num; i++) {
reg = &regs->reg[i];
if (nocheck)
continue;
/* new data after registered region */
if (start >= reg->data + reg->size)
continue;
/* new data preceding registered region */
if (end <= reg->data) {
for (j = regs->num - 1; j >= i; j--)
memcpy(&regs->reg[j + 1], &regs->reg[j],
sizeof(*reg));
break;
}
/* new data overlapping registered region */
EFI_PRINT("%s: new region already part of another\n", __func__);
return EFI_INVALID_PARAMETER;
}
reg = &regs->reg[i];
reg->data = start;
reg->size = end - start;
regs->num++;
return EFI_SUCCESS;
}
/**
* cmp_pe_section() - compare virtual addresses of two PE image sections
* @arg1: pointer to pointer to first section header
* @arg2: pointer to pointer to second section header
*
* Compare the virtual addresses of two sections of an portable executable.
* The arguments are defined as const void * to allow usage with qsort().
*
* Return: -1 if the virtual address of arg1 is less than that of arg2,
* 0 if the virtual addresses are equal, 1 if the virtual address
* of arg1 is greater than that of arg2.
*/
static int cmp_pe_section(const void *arg1, const void *arg2)
{
const IMAGE_SECTION_HEADER *section1, *section2;
section1 = *((const IMAGE_SECTION_HEADER **)arg1);
section2 = *((const IMAGE_SECTION_HEADER **)arg2);
if (section1->VirtualAddress < section2->VirtualAddress)
return -1;
else if (section1->VirtualAddress == section2->VirtualAddress)
return 0;
else
return 1;
}
/**
* efi_prepare_aligned_image() - prepare 8-byte aligned image
* @efi: pointer to the EFI binary
* @efi_size: size of @efi binary
*
* If @efi is not 8-byte aligned, this function newly allocates
* the image buffer.
*
* Return: valid pointer to a image, return NULL if allocation fails.
*/
void *efi_prepare_aligned_image(void *efi, u64 *efi_size)
{
size_t new_efi_size;
void *new_efi;
/*
* Size must be 8-byte aligned and the trailing bytes must be
* zero'ed. Otherwise hash value may be incorrect.
*/
if (!IS_ALIGNED(*efi_size, 8)) {
new_efi_size = ALIGN(*efi_size, 8);
new_efi = calloc(new_efi_size, 1);
if (!new_efi)
return NULL;
memcpy(new_efi, efi, *efi_size);
*efi_size = new_efi_size;
return new_efi;
} else {
return efi;
}
}
/**
* efi_image_parse() - parse a PE image
* @efi: Pointer to image
* @len: Size of @efi
* @regp: Pointer to a list of regions
* @auth: Pointer to a pointer to authentication data in PE
* @auth_len: Size of @auth
*
* Parse image binary in PE32(+) format, assuming that sanity of PE image
* has been checked by a caller.
* On success, an address of authentication data in @efi and its size will
* be returned in @auth and @auth_len, respectively.
*
* Return: true on success, false on error
*/
bool efi_image_parse(void *efi, size_t len, struct efi_image_regions **regp,
WIN_CERTIFICATE **auth, size_t *auth_len)
{
struct efi_image_regions *regs;
IMAGE_DOS_HEADER *dos;
IMAGE_NT_HEADERS32 *nt;
IMAGE_SECTION_HEADER *sections, **sorted;
int num_regions, num_sections, i;
int ctidx = IMAGE_DIRECTORY_ENTRY_SECURITY;
u32 align, size, authsz, authoff;
size_t bytes_hashed;
dos = (void *)efi;
nt = (void *)(efi + dos->e_lfanew);
authoff = 0;
authsz = 0;
/*
* Count maximum number of regions to be digested.
* We don't have to have an exact number here.
* See efi_image_region_add()'s in parsing below.
*/
num_regions = 3; /* for header */
num_regions += nt->FileHeader.NumberOfSections;
num_regions++; /* for extra */
regs = calloc(sizeof(*regs) + sizeof(struct image_region) * num_regions,
1);
if (!regs)
goto err;
regs->max = num_regions;
/*
* Collect data regions for hash calculation
* 1. File headers
*/
if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR64_MAGIC) {
IMAGE_NT_HEADERS64 *nt64 = (void *)nt;
IMAGE_OPTIONAL_HEADER64 *opt = &nt64->OptionalHeader;
/* Skip CheckSum */
efi_image_region_add(regs, efi, &opt->CheckSum, 0);
if (nt64->OptionalHeader.NumberOfRvaAndSizes <= ctidx) {
efi_image_region_add(regs,
&opt->Subsystem,
efi + opt->SizeOfHeaders, 0);
} else {
/* Skip Certificates Table */
efi_image_region_add(regs,
&opt->Subsystem,
&opt->DataDirectory[ctidx], 0);
efi_image_region_add(regs,
&opt->DataDirectory[ctidx] + 1,
efi + opt->SizeOfHeaders, 0);
authoff = opt->DataDirectory[ctidx].VirtualAddress;
authsz = opt->DataDirectory[ctidx].Size;
}
bytes_hashed = opt->SizeOfHeaders;
align = opt->FileAlignment;
} else if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
IMAGE_OPTIONAL_HEADER32 *opt = &nt->OptionalHeader;
/* Skip CheckSum */
efi_image_region_add(regs, efi, &opt->CheckSum, 0);
if (nt->OptionalHeader.NumberOfRvaAndSizes <= ctidx) {
efi_image_region_add(regs,
&opt->Subsystem,
efi + opt->SizeOfHeaders, 0);
} else {
/* Skip Certificates Table */
efi_image_region_add(regs, &opt->Subsystem,
&opt->DataDirectory[ctidx], 0);
efi_image_region_add(regs,
&opt->DataDirectory[ctidx] + 1,
efi + opt->SizeOfHeaders, 0);
authoff = opt->DataDirectory[ctidx].VirtualAddress;
authsz = opt->DataDirectory[ctidx].Size;
}
bytes_hashed = opt->SizeOfHeaders;
align = opt->FileAlignment;
} else {
EFI_PRINT("%s: Invalid optional header magic %x\n", __func__,
nt->OptionalHeader.Magic);
goto err;
}
/* 2. Sections */
num_sections = nt->FileHeader.NumberOfSections;
sections = (void *)((uint8_t *)&nt->OptionalHeader +
nt->FileHeader.SizeOfOptionalHeader);
sorted = calloc(sizeof(IMAGE_SECTION_HEADER *), num_sections);
if (!sorted) {
EFI_PRINT("%s: Out of memory\n", __func__);
goto err;
}
/*
* Make sure the section list is in ascending order.
*/
for (i = 0; i < num_sections; i++)
sorted[i] = &sections[i];
qsort(sorted, num_sections, sizeof(sorted[0]), cmp_pe_section);
for (i = 0; i < num_sections; i++) {
if (!sorted[i]->SizeOfRawData)
continue;
size = (sorted[i]->SizeOfRawData + align - 1) & ~(align - 1);
efi_image_region_add(regs, efi + sorted[i]->PointerToRawData,
efi + sorted[i]->PointerToRawData + size,
0);
EFI_PRINT("section[%d](%s): raw: 0x%x-0x%x, virt: %x-%x\n",
i, sorted[i]->Name,
sorted[i]->PointerToRawData,
sorted[i]->PointerToRawData + size,
sorted[i]->VirtualAddress,
sorted[i]->VirtualAddress
+ sorted[i]->Misc.VirtualSize);
bytes_hashed += size;
}
free(sorted);
/* 3. Extra data excluding Certificates Table */
if (bytes_hashed + authsz < len) {
EFI_PRINT("extra data for hash: %zu\n",
len - (bytes_hashed + authsz));
efi_image_region_add(regs, efi + bytes_hashed,
efi + len - authsz, 0);
}
/* Return Certificates Table */
if (authsz) {
if (len < authoff + authsz) {
EFI_PRINT("%s: Size for auth too large: %u >= %zu\n",
__func__, authsz, len - authoff);
goto err;
}
if (authsz < sizeof(*auth)) {
EFI_PRINT("%s: Size for auth too small: %u < %zu\n",
__func__, authsz, sizeof(*auth));
goto err;
}
*auth = efi + authoff;
*auth_len = authsz;
EFI_PRINT("WIN_CERTIFICATE: 0x%x, size: 0x%x\n", authoff,
authsz);
} else {
*auth = NULL;
*auth_len = 0;
}
*regp = regs;
return true;
err:
free(regs);
return false;
}
#ifdef CONFIG_EFI_SECURE_BOOT
/**
* efi_image_unsigned_authenticate() - authenticate unsigned image with
* SHA256 hash
* @regs: List of regions to be verified
*
* If an image is not signed, it doesn't have a signature. In this case,
* its message digest is calculated and it will be compared with one of
* hash values stored in signature databases.
*
* Return: true if authenticated, false if not
*/
static bool efi_image_unsigned_authenticate(struct efi_image_regions *regs)
{
struct efi_signature_store *db = NULL, *dbx = NULL;
bool ret = false;
dbx = efi_sigstore_parse_sigdb(L"dbx");
if (!dbx) {
EFI_PRINT("Getting signature database(dbx) failed\n");
goto out;
}
db = efi_sigstore_parse_sigdb(L"db");
if (!db) {
EFI_PRINT("Getting signature database(db) failed\n");
goto out;
}
/* try black-list first */
if (efi_signature_lookup_digest(regs, dbx)) {
EFI_PRINT("Image is not signed and its digest found in \"dbx\"\n");
goto out;
}
/* try white-list */
if (efi_signature_lookup_digest(regs, db))
ret = true;
else
EFI_PRINT("Image is not signed and its digest not found in \"db\" or \"dbx\"\n");
out:
efi_sigstore_free(db);
efi_sigstore_free(dbx);
return ret;
}
/**
* efi_image_authenticate() - verify a signature of signed image
* @efi: Pointer to image
* @efi_size: Size of @efi
*
* A signed image should have its signature stored in a table of its PE header.
* So if an image is signed and only if if its signature is verified using
* signature databases, an image is authenticated.
* If an image is not signed, its validity is checked by using
* efi_image_unsigned_authenticated().
* TODO:
* When AuditMode==0, if the image's signature is not found in
* the authorized database, or is found in the forbidden database,
* the image will not be started and instead, information about it
* will be placed in this table.
* When AuditMode==1, an EFI_IMAGE_EXECUTION_INFO element is created
* in the EFI_IMAGE_EXECUTION_INFO_TABLE for every certificate found
* in the certificate table of every image that is validated.
*
* Return: true if authenticated, false if not
*/
static bool efi_image_authenticate(void *efi, size_t efi_size)
{
struct efi_image_regions *regs = NULL;
WIN_CERTIFICATE *wincerts = NULL, *wincert;
size_t wincerts_len;
struct pkcs7_message *msg = NULL;
struct efi_signature_store *db = NULL, *dbx = NULL;
void *new_efi = NULL;
u8 *auth, *wincerts_end;
size_t auth_size;
bool ret = false;
EFI_PRINT("%s: Enter, %d\n", __func__, ret);
if (!efi_secure_boot_enabled())
return true;
new_efi = efi_prepare_aligned_image(efi, (u64 *)&efi_size);
if (!new_efi)
return false;
if (!efi_image_parse(new_efi, efi_size, &regs, &wincerts,
&wincerts_len)) {
EFI_PRINT("Parsing PE executable image failed\n");
goto err;
}
if (!wincerts) {
/* The image is not signed */
ret = efi_image_unsigned_authenticate(regs);
goto err;
}
/*
* verify signature using db and dbx
*/
db = efi_sigstore_parse_sigdb(L"db");
if (!db) {
EFI_PRINT("Getting signature database(db) failed\n");
goto err;
}
dbx = efi_sigstore_parse_sigdb(L"dbx");
if (!dbx) {
EFI_PRINT("Getting signature database(dbx) failed\n");
goto err;
}
if (efi_signature_lookup_digest(regs, dbx)) {
EFI_PRINT("Image's digest was found in \"dbx\"\n");
goto err;
}
/*
* go through WIN_CERTIFICATE list
* NOTE:
* We may have multiple signatures either as WIN_CERTIFICATE's
* in PE header, or as pkcs7 SignerInfo's in SignedData.
* So the verification policy here is:
* - Success if, at least, one of signatures is verified
* - unless signature is rejected explicitly with its digest.
*/
for (wincert = wincerts, wincerts_end = (u8 *)wincerts + wincerts_len;
(u8 *)wincert < wincerts_end;
wincert = (WIN_CERTIFICATE *)
((u8 *)wincert + ALIGN(wincert->dwLength, 8))) {
if ((u8 *)wincert + sizeof(*wincert) >= wincerts_end)
break;
if (wincert->dwLength <= sizeof(*wincert)) {
EFI_PRINT("dwLength too small: %u < %zu\n",
wincert->dwLength, sizeof(*wincert));
continue;
}
EFI_PRINT("WIN_CERTIFICATE_TYPE: 0x%x\n",
wincert->wCertificateType);
auth = (u8 *)wincert + sizeof(*wincert);
auth_size = wincert->dwLength - sizeof(*wincert);
if (wincert->wCertificateType == WIN_CERT_TYPE_EFI_GUID) {
if (auth + sizeof(efi_guid_t) >= wincerts_end)
break;
if (auth_size <= sizeof(efi_guid_t)) {
EFI_PRINT("dwLength too small: %u < %zu\n",
wincert->dwLength, sizeof(*wincert));
continue;
}
if (guidcmp(auth, &efi_guid_cert_type_pkcs7)) {
EFI_PRINT("Certificate type not supported: %pUl\n",
auth);
continue;
}
auth += sizeof(efi_guid_t);
auth_size -= sizeof(efi_guid_t);
} else if (wincert->wCertificateType
!= WIN_CERT_TYPE_PKCS_SIGNED_DATA) {
EFI_PRINT("Certificate type not supported\n");
continue;
}
msg = pkcs7_parse_message(auth, auth_size);
if (IS_ERR(msg)) {
EFI_PRINT("Parsing image's signature failed\n");
msg = NULL;
continue;
}
/*
* NOTE:
* UEFI specification defines two signature types possible
* in signature database:
* a. x509 certificate, where a signature in image is
* a message digest encrypted by RSA public key
* (EFI_CERT_X509_GUID)
* b. bare hash value of message digest
* (EFI_CERT_SHAxxx_GUID)
*
* efi_signature_verify() handles case (a), while
* efi_signature_lookup_digest() handles case (b).
*
* There is a third type:
* c. message digest of a certificate
* (EFI_CERT_X509_SHAAxxx_GUID)
* This type of signature is used only in revocation list
* (dbx) and handled as part of efi_signatgure_verify().
*/
/* try black-list first */
if (efi_signature_verify_one(regs, msg, dbx)) {
EFI_PRINT("Signature was rejected by \"dbx\"\n");
continue;
}
if (!efi_signature_check_signers(msg, dbx)) {
EFI_PRINT("Signer(s) in \"dbx\"\n");
continue;
}
/* try white-list */
if (efi_signature_verify(regs, msg, db, dbx)) {
ret = true;
break;
}
EFI_PRINT("Signature was not verified by \"db\"\n");
if (efi_signature_lookup_digest(regs, db)) {
ret = true;
break;
}
EFI_PRINT("Image's digest was not found in \"db\" or \"dbx\"\n");
}
err:
efi_sigstore_free(db);
efi_sigstore_free(dbx);
pkcs7_free_message(msg);
free(regs);
if (new_efi != efi)
free(new_efi);
EFI_PRINT("%s: Exit, %d\n", __func__, ret);
return ret;
}
#else
static bool efi_image_authenticate(void *efi, size_t efi_size)
{
return true;
}
#endif /* CONFIG_EFI_SECURE_BOOT */
/**
* efi_check_pe() - check if a memory buffer contains a PE-COFF image
*
* @buffer: buffer to check
* @size: size of buffer
* @nt_header: on return pointer to NT header of PE-COFF image
* Return: EFI_SUCCESS if the buffer contains a PE-COFF image
*/
efi_status_t efi_check_pe(void *buffer, size_t size, void **nt_header)
{
IMAGE_DOS_HEADER *dos = buffer;
IMAGE_NT_HEADERS32 *nt;
if (size < sizeof(*dos))
return EFI_INVALID_PARAMETER;
/* Check for DOS magix */
if (dos->e_magic != IMAGE_DOS_SIGNATURE)
return EFI_INVALID_PARAMETER;
/*
* Check if the image section header fits into the file. Knowing that at
* least one section header follows we only need to check for the length
* of the 64bit header which is longer than the 32bit header.
*/
if (size < dos->e_lfanew + sizeof(IMAGE_NT_HEADERS32))
return EFI_INVALID_PARAMETER;
nt = (IMAGE_NT_HEADERS32 *)((u8 *)buffer + dos->e_lfanew);
/* Check for PE-COFF magic */
if (nt->Signature != IMAGE_NT_SIGNATURE)
return EFI_INVALID_PARAMETER;
if (nt_header)
*nt_header = nt;
return EFI_SUCCESS;
}
/**
* section_size() - determine size of section
*
* The size of a section in memory if normally given by VirtualSize.
* If VirtualSize is not provided, use SizeOfRawData.
*
* @sec: section header
* Return: size of section in memory
*/
static u32 section_size(IMAGE_SECTION_HEADER *sec)
{
if (sec->Misc.VirtualSize)
return sec->Misc.VirtualSize;
else
return sec->SizeOfRawData;
}
/**
* efi_load_pe() - relocate EFI binary
*
* This function loads all sections from a PE binary into a newly reserved
* piece of memory. On success the entry point is returned as handle->entry.
*
* @handle: loaded image handle
* @efi: pointer to the EFI binary
* @efi_size: size of @efi binary
* @loaded_image_info: loaded image protocol
* Return: status code
*/
efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle,
void *efi, size_t efi_size,
struct efi_loaded_image *loaded_image_info)
{
IMAGE_NT_HEADERS32 *nt;
IMAGE_DOS_HEADER *dos;
IMAGE_SECTION_HEADER *sections;
int num_sections;
void *efi_reloc;
int i;
const IMAGE_BASE_RELOCATION *rel;
unsigned long rel_size;
int rel_idx = IMAGE_DIRECTORY_ENTRY_BASERELOC;
uint64_t image_base;
unsigned long virt_size = 0;
int supported = 0;
efi_status_t ret;
ret = efi_check_pe(efi, efi_size, (void **)&nt);
if (ret != EFI_SUCCESS) {
log_err("Not a PE-COFF file\n");
return EFI_LOAD_ERROR;
}
for (i = 0; machines[i]; i++)
if (machines[i] == nt->FileHeader.Machine) {
supported = 1;
break;
}
if (!supported) {
log_err("Machine type 0x%04x is not supported\n",
nt->FileHeader.Machine);
return EFI_LOAD_ERROR;
}
num_sections = nt->FileHeader.NumberOfSections;
sections = (void *)&nt->OptionalHeader +
nt->FileHeader.SizeOfOptionalHeader;
if (efi_size < ((void *)sections + sizeof(sections[0]) * num_sections
- efi)) {
log_err("Invalid number of sections: %d\n", num_sections);
return EFI_LOAD_ERROR;
}
/* Authenticate an image */
if (efi_image_authenticate(efi, efi_size)) {
handle->auth_status = EFI_IMAGE_AUTH_PASSED;
} else {
handle->auth_status = EFI_IMAGE_AUTH_FAILED;
log_err("Image not authenticated\n");
}
/* Calculate upper virtual address boundary */
for (i = num_sections - 1; i >= 0; i--) {
IMAGE_SECTION_HEADER *sec = &sections[i];
virt_size = max_t(unsigned long, virt_size,
sec->VirtualAddress + section_size(sec));
}
/* Read 32/64bit specific header bits */
if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR64_MAGIC) {
IMAGE_NT_HEADERS64 *nt64 = (void *)nt;
IMAGE_OPTIONAL_HEADER64 *opt = &nt64->OptionalHeader;
image_base = opt->ImageBase;
efi_set_code_and_data_type(loaded_image_info, opt->Subsystem);
handle->image_type = opt->Subsystem;
efi_reloc = efi_alloc_aligned_pages(virt_size,
loaded_image_info->image_code_type,
opt->SectionAlignment);
if (!efi_reloc) {
log_err("Out of memory\n");
ret = EFI_OUT_OF_RESOURCES;
goto err;
}
handle->entry = efi_reloc + opt->AddressOfEntryPoint;
rel_size = opt->DataDirectory[rel_idx].Size;
rel = efi_reloc + opt->DataDirectory[rel_idx].VirtualAddress;
} else if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
IMAGE_OPTIONAL_HEADER32 *opt = &nt->OptionalHeader;
image_base = opt->ImageBase;
efi_set_code_and_data_type(loaded_image_info, opt->Subsystem);
handle->image_type = opt->Subsystem;
efi_reloc = efi_alloc_aligned_pages(virt_size,
loaded_image_info->image_code_type,
opt->SectionAlignment);
if (!efi_reloc) {
log_err("Out of memory\n");
ret = EFI_OUT_OF_RESOURCES;
goto err;
}
handle->entry = efi_reloc + opt->AddressOfEntryPoint;
rel_size = opt->DataDirectory[rel_idx].Size;
rel = efi_reloc + opt->DataDirectory[rel_idx].VirtualAddress;
} else {
log_err("Invalid optional header magic %x\n",
nt->OptionalHeader.Magic);
ret = EFI_LOAD_ERROR;
goto err;
}
#if CONFIG_IS_ENABLED(EFI_TCG2_PROTOCOL)
/* Measure an PE/COFF image */
if (tcg2_measure_pe_image(efi, efi_size, handle,
loaded_image_info))
log_err("PE image measurement failed\n");
#endif
/* Copy PE headers */
memcpy(efi_reloc, efi,
sizeof(*dos)
+ sizeof(*nt)
+ nt->FileHeader.SizeOfOptionalHeader
+ num_sections * sizeof(IMAGE_SECTION_HEADER));
/* Load sections into RAM */
for (i = num_sections - 1; i >= 0; i--) {
IMAGE_SECTION_HEADER *sec = &sections[i];
u32 copy_size = section_size(sec);
if (copy_size > sec->SizeOfRawData) {
copy_size = sec->SizeOfRawData;
memset(efi_reloc + sec->VirtualAddress, 0,
sec->Misc.VirtualSize);
}
memcpy(efi_reloc + sec->VirtualAddress,
efi + sec->PointerToRawData,
copy_size);
}
/* Run through relocations */
if (efi_loader_relocate(rel, rel_size, efi_reloc,
(unsigned long)image_base) != EFI_SUCCESS) {
efi_free_pages((uintptr_t) efi_reloc,
(virt_size + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT);
ret = EFI_LOAD_ERROR;
goto err;
}
/* Flush cache */
flush_cache((ulong)efi_reloc,
ALIGN(virt_size, EFI_CACHELINE_SIZE));
invalidate_icache_all();
/* Populate the loaded image interface bits */
loaded_image_info->image_base = efi_reloc;
loaded_image_info->image_size = virt_size;
if (handle->auth_status == EFI_IMAGE_AUTH_PASSED)
return EFI_SUCCESS;
else
return EFI_SECURITY_VIOLATION;
err:
return ret;
}