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// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2020 Intel Corporation <www.intel.com>
*
*/
#include <asm/arch/mailbox_s10.h>
#include <asm/arch/secure_vab.h>
#include <asm/arch/smc_api.h>
#include <asm/unaligned.h>
#include <common.h>
#include <exports.h>
#include <linux/errno.h>
#include <linux/intel-smc.h>
#include <log.h>
#define CHUNKSZ_PER_WD_RESET (256 * SZ_1K)
/*
* Read the length of the VAB certificate from the end of image
* and calculate the actual image size (excluding the VAB certificate).
*/
static size_t get_img_size(u8 *img_buf, size_t img_buf_sz)
{
u8 *img_buf_end = img_buf + img_buf_sz;
u32 cert_sz = get_unaligned_le32(img_buf_end - sizeof(u32));
u8 *p = img_buf_end - cert_sz - sizeof(u32);
/* Ensure p is pointing within the img_buf */
if (p < img_buf || p > (img_buf_end - VAB_CERT_HEADER_SIZE))
return 0;
if (get_unaligned_le32(p) == SDM_CERT_MAGIC_NUM)
return (size_t)(p - img_buf);
return 0;
}
/*
* Vendor Authorized Boot (VAB) is a security feature for authenticating
* the images such as U-Boot, ARM trusted Firmware, Linux kernel,
* device tree blob and etc loaded from FIT. User can also trigger
* the VAB authentication from U-Boot command.
*
* This function extracts the VAB certificate and signature block
* appended at the end of the image, then send to Secure Device Manager
* (SDM) for authentication. This function will validate the SHA384
* of the image against the SHA384 hash stored in the VAB certificate
* before sending the VAB certificate to SDM for authentication.
*
* RETURN
* 0 if authentication success or
* if authentication is not required and bypassed on a non-secure device
* negative error code if authentication fail
*/
int socfpga_vendor_authentication(void **p_image, size_t *p_size)
{
int retry_count = 20;
u8 hash384[SHA384_SUM_LEN];
u64 img_addr, mbox_data_addr;
size_t img_sz, mbox_data_sz;
u8 *cert_hash_ptr, *mbox_relocate_data_addr;
u32 resp = 0, resp_len = 1;
int ret;
img_addr = (uintptr_t)*p_image;
debug("Authenticating image at address 0x%016llx (%ld bytes)\n",
img_addr, *p_size);
img_sz = get_img_size((u8 *)img_addr, *p_size);
debug("img_sz = %ld\n", img_sz);
if (!img_sz) {
puts("VAB certificate not found in image!\n");
return -ENOKEY;
}
if (!IS_ALIGNED(img_sz, sizeof(u32))) {
printf("Image size (%ld bytes) not aliged to 4 bytes!\n",
img_sz);
return -EBFONT;
}
/* Generate HASH384 from the image */
sha384_csum_wd((u8 *)img_addr, img_sz, hash384, CHUNKSZ_PER_WD_RESET);
cert_hash_ptr = (u8 *)(img_addr + img_sz + VAB_CERT_MAGIC_OFFSET +
VAB_CERT_FIT_SHA384_OFFSET);
/*
* Compare the SHA384 found in certificate against the SHA384
* calculated from image
*/
if (memcmp(hash384, cert_hash_ptr, SHA384_SUM_LEN)) {
puts("SHA384 not match!\n");
return -EKEYREJECTED;
}
mbox_data_addr = img_addr + img_sz - sizeof(u32);
/* Size in word (32bits) */
mbox_data_sz = (ALIGN(*p_size - img_sz, sizeof(u32))) >> 2;
debug("mbox_data_addr = 0x%016llx\n", mbox_data_addr);
debug("mbox_data_sz = %ld words\n", mbox_data_sz);
/*
* Relocate certificate to first memory block before trigger SMC call
* to send mailbox command because ATF only able to access first
* memory block.
*/
mbox_relocate_data_addr = (u8 *)malloc(mbox_data_sz * sizeof(u32));
if (!mbox_relocate_data_addr) {
puts("Out of memory for VAB certificate relocation!\n");
return -ENOMEM;
}
memcpy(mbox_relocate_data_addr, (u8 *)mbox_data_addr, mbox_data_sz * sizeof(u32));
*(u32 *)mbox_relocate_data_addr = 0;
debug("mbox_relocate_data_addr = 0x%p\n", mbox_relocate_data_addr);
do {
if (!IS_ENABLED(CONFIG_SPL_BUILD) && IS_ENABLED(CONFIG_SPL_ATF)) {
/* Invoke SMC call to ATF to send the VAB certificate to SDM */
ret = smc_send_mailbox(MBOX_VAB_SRC_CERT, mbox_data_sz,
(u32 *)mbox_relocate_data_addr, 0, &resp_len,
&resp);
} else {
/* Send the VAB certficate to SDM for authentication */
ret = mbox_send_cmd(MBOX_ID_UBOOT, MBOX_VAB_SRC_CERT,
MBOX_CMD_DIRECT, mbox_data_sz,
(u32 *)mbox_relocate_data_addr, 0, &resp_len,
&resp);
}
/* If SDM is not available, just delay 50ms and retry again */
if (ret == MBOX_RESP_DEVICE_BUSY)
mdelay(50);
else
break;
} while (--retry_count);
/* Free the relocate certificate memory space */
free(mbox_relocate_data_addr);
/* Exclude the size of the VAB certificate from image size */
*p_size = img_sz;
debug("ret = 0x%08x, resp = 0x%08x, resp_len = %d\n", ret, resp,
resp_len);
if (ret) {
/*
* Unsupported mailbox command or device not in the
* owned/secure state
*/
if (ret == MBOX_RESP_NOT_ALLOWED_UNDER_SECURITY_SETTINGS) {
/* SDM bypass authentication */
printf("%s 0x%016llx (%ld bytes)\n",
"Image Authentication bypassed at address",
img_addr, img_sz);
return 0;
}
puts("VAB certificate authentication failed in SDM");
if (ret == MBOX_RESP_DEVICE_BUSY) {
puts(" (SDM busy timeout)\n");
return -ETIMEDOUT;
} else if (ret == MBOX_RESP_UNKNOWN) {
puts(" (Not supported)\n");
return -ESRCH;
}
puts("\n");
return -EKEYREJECTED;
} else {
/* If Certificate Process Status has error */
if (resp) {
puts("VAB certificate process failed\n");
return -ENOEXEC;
}
}
printf("%s 0x%016llx (%ld bytes)\n",
"Image Authentication passed at address", img_addr, img_sz);
return 0;
}
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