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// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2018 Xilinx, Inc.
*/
#include <common.h>
#include <command.h>
#include <log.h>
#include <asm/io.h>
#include <asm/arch/hardware.h>
#include <asm/arch/sys_proto.h>
#include <malloc.h>
#include <linux/bitops.h>
#include <u-boot/md5.h>
#include <u-boot/rsa.h>
#include <u-boot/rsa-mod-exp.h>
#include <u-boot/sha256.h>
#include <zynqpl.h>
#include <fpga.h>
#include <zynq_bootimg.h>
DECLARE_GLOBAL_DATA_PTR;
#ifdef CONFIG_CMD_ZYNQ_RSA
#define ZYNQ_EFUSE_RSA_ENABLE_MASK 0x400
#define ZYNQ_ATTRIBUTE_PL_IMAGE_MASK 0x20
#define ZYNQ_ATTRIBUTE_CHECKSUM_TYPE_MASK 0x7000
#define ZYNQ_ATTRIBUTE_RSA_PRESENT_MASK 0x8000
#define ZYNQ_ATTRIBUTE_RSA_PART_OWNER_MASK 0x30000
#define ZYNQ_RSA_MODULAR_SIZE 256
#define ZYNQ_RSA_MODULAR_EXT_SIZE 256
#define ZYNQ_RSA_EXPO_SIZE 64
#define ZYNQ_RSA_SPK_SIGNATURE_SIZE 256
#define ZYNQ_RSA_PARTITION_SIGNATURE_SIZE 256
#define ZYNQ_RSA_SIGNATURE_SIZE 0x6C0
#define ZYNQ_RSA_HEADER_SIZE 4
#define ZYNQ_RSA_MAGIC_WORD_SIZE 60
#define ZYNQ_RSA_PART_OWNER_UBOOT 1
#define ZYNQ_RSA_ALIGN_PPK_START 64
#define WORD_LENGTH_SHIFT 2
static u8 *ppkmodular;
static u8 *ppkmodularex;
struct zynq_rsa_public_key {
uint len; /* Length of modulus[] in number of u32 */
u32 n0inv; /* -1 / modulus[0] mod 2^32 */
u32 *modulus; /* modulus as little endian array */
u32 *rr; /* R^2 as little endian array */
};
static struct zynq_rsa_public_key public_key;
static struct partition_hdr part_hdr[ZYNQ_MAX_PARTITION_NUMBER];
/*
* Extract the primary public key components from already autheticated FSBL
*/
static void zynq_extract_ppk(u32 fsbl_len)
{
u32 padsize;
u8 *ppkptr;
debug("%s\n", __func__);
/*
* Extract the authenticated PPK from OCM i.e at end of the FSBL
*/
ppkptr = (u8 *)(fsbl_len + ZYNQ_OCM_BASEADDR);
padsize = ((u32)ppkptr % ZYNQ_RSA_ALIGN_PPK_START);
if (padsize)
ppkptr += (ZYNQ_RSA_ALIGN_PPK_START - padsize);
ppkptr += ZYNQ_RSA_HEADER_SIZE;
ppkptr += ZYNQ_RSA_MAGIC_WORD_SIZE;
ppkmodular = (u8 *)ppkptr;
ppkptr += ZYNQ_RSA_MODULAR_SIZE;
ppkmodularex = (u8 *)ppkptr;
ppkptr += ZYNQ_RSA_MODULAR_EXT_SIZE;
}
/*
* Calculate the inverse(-1 / modulus[0] mod 2^32 ) for the PPK
*/
static u32 zynq_calc_inv(void)
{
u32 modulus = public_key.modulus[0];
u32 tmp = BIT(1);
u32 inverse;
inverse = modulus & BIT(0);
while (tmp) {
inverse *= 2 - modulus * inverse;
tmp *= tmp;
}
return ~(inverse - 1);
}
/*
* Recreate the signature by padding the bytes and verify with hash value
*/
static int zynq_pad_and_check(u8 *signature, u8 *hash)
{
u8 padding[] = {0x30, 0x31, 0x30, 0x0D, 0x06, 0x09, 0x60, 0x86, 0x48,
0x01, 0x65, 0x03, 0x04, 0x02, 0x01, 0x05, 0x00, 0x04,
0x20};
u8 *pad_ptr = signature + 256;
u32 pad = 202;
u32 ii;
/*
* Re-Create PKCS#1v1.5 Padding
* MSB ----------------------------------------------------LSB
* 0x0 || 0x1 || 0xFF(for 202 bytes) || 0x0 || T_padding || SHA256 Hash
*/
if (*--pad_ptr != 0 || *--pad_ptr != 1)
return -1;
for (ii = 0; ii < pad; ii++) {
if (*--pad_ptr != 0xFF)
return -1;
}
if (*--pad_ptr != 0)
return -1;
for (ii = 0; ii < sizeof(padding); ii++) {
if (*--pad_ptr != padding[ii])
return -1;
}
for (ii = 0; ii < 32; ii++) {
if (*--pad_ptr != hash[ii])
return -1;
}
return 0;
}
/*
* Verify and extract the hash value from signature using the public key
* and compare it with calculated hash value.
*/
static int zynq_rsa_verify_key(const struct zynq_rsa_public_key *key,
const u8 *sig, const u32 sig_len, const u8 *hash)
{
int status;
void *buf;
if (!key || !sig || !hash)
return -1;
if (sig_len != (key->len * sizeof(u32))) {
printf("Signature is of incorrect length %d\n", sig_len);
return -1;
}
/* Sanity check for stack size */
if (sig_len > ZYNQ_RSA_SPK_SIGNATURE_SIZE) {
printf("Signature length %u exceeds maximum %d\n", sig_len,
ZYNQ_RSA_SPK_SIGNATURE_SIZE);
return -1;
}
buf = malloc(sig_len);
if (!buf)
return -1;
memcpy(buf, sig, sig_len);
status = zynq_pow_mod((u32 *)key, (u32 *)buf);
if (status == -1) {
free(buf);
return status;
}
status = zynq_pad_and_check((u8 *)buf, (u8 *)hash);
free(buf);
return status;
}
/*
* Authenticate the partition
*/
static int zynq_authenticate_part(u8 *buffer, u32 size)
{
u8 hash_signature[32];
u8 *spk_modular;
u8 *spk_modular_ex;
u8 *signature_ptr;
u32 status;
debug("%s\n", __func__);
signature_ptr = (u8 *)(buffer + size - ZYNQ_RSA_SIGNATURE_SIZE);
signature_ptr += ZYNQ_RSA_HEADER_SIZE;
signature_ptr += ZYNQ_RSA_MAGIC_WORD_SIZE;
ppkmodular = (u8 *)signature_ptr;
signature_ptr += ZYNQ_RSA_MODULAR_SIZE;
ppkmodularex = signature_ptr;
signature_ptr += ZYNQ_RSA_MODULAR_EXT_SIZE;
signature_ptr += ZYNQ_RSA_EXPO_SIZE;
sha256_csum_wd((const unsigned char *)signature_ptr,
(ZYNQ_RSA_MODULAR_EXT_SIZE + ZYNQ_RSA_EXPO_SIZE +
ZYNQ_RSA_MODULAR_SIZE),
(unsigned char *)hash_signature, 0x1000);
spk_modular = (u8 *)signature_ptr;
signature_ptr += ZYNQ_RSA_MODULAR_SIZE;
spk_modular_ex = (u8 *)signature_ptr;
signature_ptr += ZYNQ_RSA_MODULAR_EXT_SIZE;
signature_ptr += ZYNQ_RSA_EXPO_SIZE;
public_key.len = ZYNQ_RSA_MODULAR_SIZE / sizeof(u32);
public_key.modulus = (u32 *)ppkmodular;
public_key.rr = (u32 *)ppkmodularex;
public_key.n0inv = zynq_calc_inv();
status = zynq_rsa_verify_key(&public_key, signature_ptr,
ZYNQ_RSA_SPK_SIGNATURE_SIZE,
hash_signature);
if (status)
return status;
signature_ptr += ZYNQ_RSA_SPK_SIGNATURE_SIZE;
sha256_csum_wd((const unsigned char *)buffer,
(size - ZYNQ_RSA_PARTITION_SIGNATURE_SIZE),
(unsigned char *)hash_signature, 0x1000);
public_key.len = ZYNQ_RSA_MODULAR_SIZE / sizeof(u32);
public_key.modulus = (u32 *)spk_modular;
public_key.rr = (u32 *)spk_modular_ex;
public_key.n0inv = zynq_calc_inv();
return zynq_rsa_verify_key(&public_key, (u8 *)signature_ptr,
ZYNQ_RSA_PARTITION_SIGNATURE_SIZE,
(u8 *)hash_signature);
}
/*
* Parses the partition header and verfies the authenticated and
* encrypted image.
*/
static int zynq_verify_image(u32 src_ptr)
{
u32 silicon_ver, image_base_addr, status;
u32 partition_num = 0;
u32 efuseval, srcaddr, size, fsbl_len;
struct partition_hdr *hdr_ptr;
u32 part_data_len, part_img_len, part_attr;
u32 part_load_addr, part_dst_addr, part_chksum_offset;
u32 part_start_addr, part_total_size, partitioncount;
bool encrypt_part_flag = false;
bool part_chksum_flag = false;
bool signed_part_flag = false;
image_base_addr = src_ptr;
silicon_ver = zynq_get_silicon_version();
/* RSA not supported in silicon versions 1.0 and 2.0 */
if (silicon_ver == 0 || silicon_ver == 1)
return -1;
zynq_get_partition_info(image_base_addr, &fsbl_len,
&part_hdr[0]);
/* Extract ppk if efuse was blown Otherwise return error */
efuseval = readl(&efuse_base->status);
if (!(efuseval & ZYNQ_EFUSE_RSA_ENABLE_MASK))
return -1;
zynq_extract_ppk(fsbl_len);
partitioncount = zynq_get_part_count(&part_hdr[0]);
/*
* As the first two partitions are related to fsbl,
* we can ignore those two in bootimage and the below
* code doesn't need to validate it as fsbl is already
* done by now
*/
if (partitioncount <= 2 ||
partitioncount > ZYNQ_MAX_PARTITION_NUMBER)
return -1;
while (partition_num < partitioncount) {
if (((part_hdr[partition_num].partitionattr &
ZYNQ_ATTRIBUTE_RSA_PART_OWNER_MASK) >> 16) !=
ZYNQ_RSA_PART_OWNER_UBOOT) {
printf("UBOOT is not Owner for partition %d\n",
partition_num);
partition_num++;
continue;
}
hdr_ptr = &part_hdr[partition_num];
status = zynq_validate_hdr(hdr_ptr);
if (status)
return status;
part_data_len = hdr_ptr->datawordlen;
part_img_len = hdr_ptr->imagewordlen;
part_attr = hdr_ptr->partitionattr;
part_load_addr = hdr_ptr->loadaddr;
part_chksum_offset = hdr_ptr->checksumoffset;
part_start_addr = hdr_ptr->partitionstart;
part_total_size = hdr_ptr->partitionwordlen;
if (part_data_len != part_img_len) {
debug("Encrypted\n");
encrypt_part_flag = true;
}
if (part_attr & ZYNQ_ATTRIBUTE_CHECKSUM_TYPE_MASK)
part_chksum_flag = true;
if (part_attr & ZYNQ_ATTRIBUTE_RSA_PRESENT_MASK) {
debug("RSA Signed\n");
signed_part_flag = true;
size = part_total_size << WORD_LENGTH_SHIFT;
} else {
size = part_img_len;
}
if (!signed_part_flag && !part_chksum_flag) {
printf("Partition not signed & no chksum\n");
partition_num++;
continue;
}
srcaddr = image_base_addr +
(part_start_addr << WORD_LENGTH_SHIFT);
/*
* This validation is just for PS DDR.
* TODO: Update this for PL DDR check as well.
*/
if (part_load_addr < gd->bd->bi_dram[0].start &&
((part_load_addr + part_data_len) >
(gd->bd->bi_dram[0].start +
gd->bd->bi_dram[0].size))) {
printf("INVALID_LOAD_ADDRESS_FAIL\n");
return -1;
}
if (part_attr & ZYNQ_ATTRIBUTE_PL_IMAGE_MASK)
part_load_addr = srcaddr;
else
memcpy((u32 *)part_load_addr, (u32 *)srcaddr,
size);
if (part_chksum_flag) {
part_chksum_offset = image_base_addr +
(part_chksum_offset <<
WORD_LENGTH_SHIFT);
status = zynq_validate_partition(part_load_addr,
(part_total_size <<
WORD_LENGTH_SHIFT),
part_chksum_offset);
if (status != 0) {
printf("PART_CHKSUM_FAIL\n");
return -1;
}
debug("Partition Validation Done\n");
}
if (signed_part_flag) {
status = zynq_authenticate_part((u8 *)part_load_addr,
size);
if (status != 0) {
printf("AUTHENTICATION_FAIL\n");
return -1;
}
debug("Authentication Done\n");
}
if (encrypt_part_flag) {
debug("DECRYPTION\n");
part_dst_addr = part_load_addr;
if (part_attr & ZYNQ_ATTRIBUTE_PL_IMAGE_MASK) {
partition_num++;
continue;
}
status = zynq_decrypt_load(part_load_addr,
part_img_len,
part_dst_addr,
part_data_len,
BIT_NONE);
if (status != 0) {
printf("DECRYPTION_FAIL\n");
return -1;
}
}
partition_num++;
}
return 0;
}
static int do_zynq_rsa(struct cmd_tbl *cmdtp, int flag, int argc,
char *const argv[])
{
u32 src_ptr;
char *endp;
if (argc != cmdtp->maxargs)
return CMD_RET_FAILURE;
src_ptr = simple_strtoul(argv[2], &endp, 16);
if (*argv[2] == 0 || *endp != 0)
return CMD_RET_USAGE;
if (zynq_verify_image(src_ptr))
return CMD_RET_FAILURE;
return CMD_RET_SUCCESS;
}
#endif
#ifdef CONFIG_CMD_ZYNQ_AES
static int zynq_decrypt_image(struct cmd_tbl *cmdtp, int flag, int argc,
char *const argv[])
{
char *endp;
u32 srcaddr, srclen, dstaddr, dstlen;
int status;
u8 imgtype = BIT_NONE;
if (argc < 5 && argc > cmdtp->maxargs)
return CMD_RET_USAGE;
srcaddr = simple_strtoul(argv[2], &endp, 16);
if (*argv[2] == 0 || *endp != 0)
return CMD_RET_USAGE;
srclen = simple_strtoul(argv[3], &endp, 16);
if (*argv[3] == 0 || *endp != 0)
return CMD_RET_USAGE;
dstaddr = simple_strtoul(argv[4], &endp, 16);
if (*argv[4] == 0 || *endp != 0)
return CMD_RET_USAGE;
dstlen = simple_strtoul(argv[5], &endp, 16);
if (*argv[5] == 0 || *endp != 0)
return CMD_RET_USAGE;
/*
* Roundup source and destination lengths to
* word size
*/
if (srclen % 4)
srclen = roundup(srclen, 4);
if (dstlen % 4)
dstlen = roundup(dstlen, 4);
status = zynq_decrypt_load(srcaddr, srclen >> 2, dstaddr,
dstlen >> 2, imgtype);
if (status != 0)
return CMD_RET_FAILURE;
return CMD_RET_SUCCESS;
}
#endif
static struct cmd_tbl zynq_commands[] = {
#ifdef CONFIG_CMD_ZYNQ_RSA
U_BOOT_CMD_MKENT(rsa, 3, 1, do_zynq_rsa, "", ""),
#endif
#ifdef CONFIG_CMD_ZYNQ_AES
U_BOOT_CMD_MKENT(aes, 6, 1, zynq_decrypt_image, "", ""),
#endif
};
static int do_zynq(struct cmd_tbl *cmdtp, int flag, int argc,
char *const argv[])
{
struct cmd_tbl *zynq_cmd;
int ret;
if (!ARRAY_SIZE(zynq_commands)) {
puts("No zynq specific command enabled\n");
return CMD_RET_USAGE;
}
if (argc < 2)
return CMD_RET_USAGE;
zynq_cmd = find_cmd_tbl(argv[1], zynq_commands,
ARRAY_SIZE(zynq_commands));
if (!zynq_cmd)
return CMD_RET_USAGE;
ret = zynq_cmd->cmd(zynq_cmd, flag, argc, argv);
return cmd_process_error(zynq_cmd, ret);
}
#ifdef CONFIG_SYS_LONGHELP
static char zynq_help_text[] =
""
#ifdef CONFIG_CMD_ZYNQ_RSA
"rsa <baseaddr> - Verifies the authenticated and encrypted\n"
" zynq images and loads them back to load\n"
" addresses as specified in BOOT image(BOOT.BIN)\n"
#endif
#ifdef CONFIG_CMD_ZYNQ_AES
"aes <srcaddr> <srclen> <dstaddr> <dstlen>\n"
" - Decrypts the encrypted image present in source\n"
" address and places the decrypted image at\n"
" destination address\n"
#endif
;
#endif
U_BOOT_CMD(zynq, 6, 0, do_zynq,
"Zynq specific commands", zynq_help_text
);
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