u-boot/tools/mkeficapsule.c
Sughosh Ganu 322c813f4b mkeficapsule: Add support for embedding public key in a dtb
Add options for embedding the public key esl(efi signature list) file
to the platform's dtb. The esl file is then retrieved and used for
authenticating the capsule to be used for updating firmare components
on the platform.

The esl file can now be embedded in the dtb by invoking the following
command
mkeficapsule -K <pub_key.esl> -D <dtb>

In the scenario where the esl file is to be embedded in an overlay,
this can be done through the following command
mkeficapsule -O -K <pub_key.esl> -D <dtb>

This will create a node named 'signature' in the dtb, and the esl file
will be stored as 'capsule-key'

Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
2020-12-31 14:41:31 +01:00

446 lines
9.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright 2018 Linaro Limited
* Author: AKASHI Takahiro
*/
#include <errno.h>
#include <getopt.h>
#include <malloc.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <linux/types.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
#include "fdt_host.h"
typedef __u8 u8;
typedef __u16 u16;
typedef __u32 u32;
typedef __u64 u64;
typedef __s16 s16;
typedef __s32 s32;
#define aligned_u64 __aligned_u64
#define SIGNATURE_NODENAME "signature"
#define OVERLAY_NODENAME "__overlay__"
#ifndef __packed
#define __packed __attribute__((packed))
#endif
#include <efi.h>
#include <efi_api.h>
static const char *tool_name = "mkeficapsule";
efi_guid_t efi_guid_fm_capsule = EFI_FIRMWARE_MANAGEMENT_CAPSULE_ID_GUID;
efi_guid_t efi_guid_image_type_uboot_fit =
EFI_FIRMWARE_IMAGE_TYPE_UBOOT_FIT_GUID;
efi_guid_t efi_guid_image_type_uboot_raw =
EFI_FIRMWARE_IMAGE_TYPE_UBOOT_RAW_GUID;
static struct option options[] = {
{"fit", required_argument, NULL, 'f'},
{"raw", required_argument, NULL, 'r'},
{"index", required_argument, NULL, 'i'},
{"instance", required_argument, NULL, 'I'},
{"dtb", required_argument, NULL, 'D'},
{"public key", required_argument, NULL, 'K'},
{"overlay", no_argument, NULL, 'O'},
{"help", no_argument, NULL, 'h'},
{NULL, 0, NULL, 0},
};
static void print_usage(void)
{
printf("Usage: %s [options] <output file>\n"
"Options:\n"
"\t--fit <fit image> new FIT image file\n"
"\t--raw <raw image> new raw image file\n"
"\t--index <index> update image index\n"
"\t--instance <instance> update hardware instance\n"
"\t--public-key <key file> public key esl file\n"
"\t--dtb <dtb file> dtb file\n"
"\t--overlay the dtb file is an overlay\n"
"\t--help print a help message\n",
tool_name);
}
static int fdt_add_pub_key_data(void *sptr, void *dptr, size_t key_size,
bool overlay)
{
int parent;
int ov_node;
int frag_node;
int ret = 0;
if (overlay) {
/*
* The signature would be stored in the
* first fragment node of the overlay
*/
frag_node = fdt_first_subnode(dptr, 0);
if (frag_node == -FDT_ERR_NOTFOUND) {
fprintf(stderr,
"Couldn't find the fragment node: %s\n",
fdt_strerror(frag_node));
goto done;
}
ov_node = fdt_subnode_offset(dptr, frag_node, OVERLAY_NODENAME);
if (ov_node == -FDT_ERR_NOTFOUND) {
fprintf(stderr,
"Couldn't find the __overlay__ node: %s\n",
fdt_strerror(ov_node));
goto done;
}
} else {
ov_node = 0;
}
parent = fdt_subnode_offset(dptr, ov_node, SIGNATURE_NODENAME);
if (parent == -FDT_ERR_NOTFOUND) {
parent = fdt_add_subnode(dptr, ov_node, SIGNATURE_NODENAME);
if (parent < 0) {
ret = parent;
if (ret != -FDT_ERR_NOSPACE) {
fprintf(stderr,
"Couldn't create signature node: %s\n",
fdt_strerror(parent));
}
}
}
if (ret)
goto done;
/* Write the key to the FDT node */
ret = fdt_setprop(dptr, parent, "capsule-key",
sptr, key_size);
done:
if (ret)
ret = ret == -FDT_ERR_NOSPACE ? -ENOSPC : -EIO;
return ret;
}
static int add_public_key(const char *pkey_file, const char *dtb_file,
bool overlay)
{
int ret;
int srcfd = 0;
int destfd = 0;
void *sptr = NULL;
void *dptr = NULL;
off_t src_size;
struct stat pub_key;
struct stat dtb;
/* Find out the size of the public key */
srcfd = open(pkey_file, O_RDONLY);
if (srcfd == -1) {
fprintf(stderr, "%s: Can't open %s: %s\n",
__func__, pkey_file, strerror(errno));
goto err;
}
ret = fstat(srcfd, &pub_key);
if (ret == -1) {
fprintf(stderr, "%s: Can't stat %s: %s\n",
__func__, pkey_file, strerror(errno));
goto err;
}
src_size = pub_key.st_size;
/* mmap the public key esl file */
sptr = mmap(0, src_size, PROT_READ, MAP_SHARED, srcfd, 0);
if ((sptr == MAP_FAILED) || (errno != 0)) {
fprintf(stderr, "%s: Failed to mmap %s:%s\n",
__func__, pkey_file, strerror(errno));
goto err;
}
/* Open the dest FDT */
destfd = open(dtb_file, O_RDWR);
if (destfd == -1) {
fprintf(stderr, "%s: Can't open %s: %s\n",
__func__, dtb_file, strerror(errno));
goto err;
}
ret = fstat(destfd, &dtb);
if (ret == -1) {
fprintf(stderr, "%s: Can't stat %s: %s\n",
__func__, dtb_file, strerror(errno));
goto err;
}
dtb.st_size += src_size + 0x30;
if (ftruncate(destfd, dtb.st_size)) {
fprintf(stderr, "%s: Can't expand %s: %s\n",
__func__, dtb_file, strerror(errno));
goto err;;
}
errno = 0;
/* mmap the dtb file */
dptr = mmap(0, dtb.st_size, PROT_READ | PROT_WRITE, MAP_SHARED,
destfd, 0);
if ((dptr == MAP_FAILED) || (errno != 0)) {
fprintf(stderr, "%s: Failed to mmap %s:%s\n",
__func__, dtb_file, strerror(errno));
goto err;
}
if (fdt_check_header(dptr)) {
fprintf(stderr, "%s: Invalid FDT header\n", __func__);
goto err;
}
ret = fdt_open_into(dptr, dptr, dtb.st_size);
if (ret) {
fprintf(stderr, "%s: Cannot expand FDT: %s\n",
__func__, fdt_strerror(ret));
goto err;
}
/* Copy the esl file to the expanded FDT */
ret = fdt_add_pub_key_data(sptr, dptr, src_size, overlay);
if (ret < 0) {
fprintf(stderr, "%s: Unable to add public key to the FDT\n",
__func__);
goto err;
}
return 0;
err:
if (sptr)
munmap(sptr, src_size);
if (dptr)
munmap(dptr, dtb.st_size);
if (srcfd >= 0)
close(srcfd);
if (destfd >= 0)
close(destfd);
return -1;
}
static int create_fwbin(char *path, char *bin, efi_guid_t *guid,
unsigned long index, unsigned long instance)
{
struct efi_capsule_header header;
struct efi_firmware_management_capsule_header capsule;
struct efi_firmware_management_capsule_image_header image;
FILE *f, *g;
struct stat bin_stat;
u8 *data;
size_t size;
u64 offset;
#ifdef DEBUG
printf("For output: %s\n", path);
printf("\tbin: %s\n\ttype: %pUl\n" bin, guid);
printf("\tindex: %ld\n\tinstance: %ld\n", index, instance);
#endif
g = fopen(bin, "r");
if (!g) {
printf("cannot open %s\n", bin);
return -1;
}
if (stat(bin, &bin_stat) < 0) {
printf("cannot determine the size of %s\n", bin);
goto err_1;
}
data = malloc(bin_stat.st_size);
if (!data) {
printf("cannot allocate memory: %lx\n", bin_stat.st_size);
goto err_1;
}
f = fopen(path, "w");
if (!f) {
printf("cannot open %s\n", path);
goto err_2;
}
header.capsule_guid = efi_guid_fm_capsule;
header.header_size = sizeof(header);
/* TODO: The current implementation ignores flags */
header.flags = CAPSULE_FLAGS_PERSIST_ACROSS_RESET;
header.capsule_image_size = sizeof(header)
+ sizeof(capsule) + sizeof(u64)
+ sizeof(image)
+ bin_stat.st_size;
size = fwrite(&header, 1, sizeof(header), f);
if (size < sizeof(header)) {
printf("write failed (%lx)\n", size);
goto err_3;
}
capsule.version = 0x00000001;
capsule.embedded_driver_count = 0;
capsule.payload_item_count = 1;
size = fwrite(&capsule, 1, sizeof(capsule), f);
if (size < (sizeof(capsule))) {
printf("write failed (%lx)\n", size);
goto err_3;
}
offset = sizeof(capsule) + sizeof(u64);
size = fwrite(&offset, 1, sizeof(offset), f);
if (size < sizeof(offset)) {
printf("write failed (%lx)\n", size);
goto err_3;
}
image.version = 0x00000003;
memcpy(&image.update_image_type_id, guid, sizeof(*guid));
image.update_image_index = index;
image.update_image_size = bin_stat.st_size;
image.update_vendor_code_size = 0; /* none */
image.update_hardware_instance = instance;
image.image_capsule_support = 0;
size = fwrite(&image, 1, sizeof(image), f);
if (size < sizeof(image)) {
printf("write failed (%lx)\n", size);
goto err_3;
}
size = fread(data, 1, bin_stat.st_size, g);
if (size < bin_stat.st_size) {
printf("read failed (%lx)\n", size);
goto err_3;
}
size = fwrite(data, 1, bin_stat.st_size, f);
if (size < bin_stat.st_size) {
printf("write failed (%lx)\n", size);
goto err_3;
}
fclose(f);
fclose(g);
free(data);
return 0;
err_3:
fclose(f);
err_2:
free(data);
err_1:
fclose(g);
return -1;
}
/*
* Usage:
* $ mkeficapsule -f <firmware binary> <output file>
*/
int main(int argc, char **argv)
{
char *file;
char *pkey_file;
char *dtb_file;
efi_guid_t *guid;
unsigned long index, instance;
int c, idx;
int ret;
bool overlay = false;
file = NULL;
pkey_file = NULL;
dtb_file = NULL;
guid = NULL;
index = 0;
instance = 0;
for (;;) {
c = getopt_long(argc, argv, "f:r:i:I:v:D:K:Oh", options, &idx);
if (c == -1)
break;
switch (c) {
case 'f':
if (file) {
printf("Image already specified\n");
return -1;
}
file = optarg;
guid = &efi_guid_image_type_uboot_fit;
break;
case 'r':
if (file) {
printf("Image already specified\n");
return -1;
}
file = optarg;
guid = &efi_guid_image_type_uboot_raw;
break;
case 'i':
index = strtoul(optarg, NULL, 0);
break;
case 'I':
instance = strtoul(optarg, NULL, 0);
break;
case 'K':
if (pkey_file) {
printf("Public Key already specified\n");
return -1;
}
pkey_file = optarg;
break;
case 'D':
if (dtb_file) {
printf("DTB file already specified\n");
return -1;
}
dtb_file = optarg;
break;
case 'O':
overlay = true;
break;
case 'h':
print_usage();
return 0;
}
}
/* need a fit image file or raw image file */
if (!file && !pkey_file && !dtb_file) {
printf("%s: %d\n", __func__, __LINE__);
print_usage();
return -1;
}
if (pkey_file && dtb_file) {
ret = add_public_key(pkey_file, dtb_file, overlay);
if (ret == -1) {
printf("Adding public key to the dtb failed\n");
return -1;
} else {
return 0;
}
}
if (create_fwbin(argv[optind], file, guid, index, instance)
< 0) {
printf("Creating firmware capsule failed\n");
return -1;
}
return 0;
}