mirror of
https://github.com/brain-hackers/u-boot-brain
synced 2024-06-09 23:36:03 +09:00
c5de15cbc8
Freescale's SEC block has built-in Blob Protocol which provides
a method for protecting user-defined data across system power
cycles. SEC block protects data in a data structure called a Blob,
which provides both confidentiality and integrity protection.
Encapsulating data as a blob
Each time that the Blob Protocol is used to protect data, a
different randomly generated key is used to encrypt the data.
This random key is itself encrypted using a key which is derived
from SoC's non volatile secret key and a 16 bit Key identifier.
The resulting encrypted key along with encrypted data is called a blob.
The non volatile secure key is available for use only during secure boot.
During decapsulation, the reverse process is performed to get back
the original data.
Commands added
--------------
blob enc - encapsulating data as a cryptgraphic blob
blob dec - decapsulating cryptgraphic blob to get the data
Commands Syntax
---------------
blob enc src dst len km
Encapsulate and create blob of data $len bytes long
at address $src and store the result at address $dst.
$km is the 16 byte key modifier is also required for
generation/use as key for cryptographic operation. Key
modifier should be 16 byte long.
blob dec src dst len km
Decapsulate the blob of data at address $src and
store result of $len byte at addr $dst.
$km is the 16 byte key modifier is also required for
generation/use as key for cryptographic operation. Key
modifier should be 16 byte long.
Signed-off-by: Ruchika Gupta <ruchika.gupta@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>
110 lines
3.1 KiB
C
110 lines
3.1 KiB
C
/*
|
|
*
|
|
* Command for encapsulating/decapsulating blob of memory.
|
|
*
|
|
* SPDX-License-Identifier: GPL-2.0+
|
|
*/
|
|
|
|
#include <common.h>
|
|
#include <command.h>
|
|
#include <environment.h>
|
|
#include <malloc.h>
|
|
#include <asm/byteorder.h>
|
|
#include <linux/compiler.h>
|
|
|
|
DECLARE_GLOBAL_DATA_PTR;
|
|
|
|
/**
|
|
* blob_decap() - Decapsulate the data as a blob
|
|
* @key_mod: - Pointer to key modifier/key
|
|
* @src: - Address of data to be decapsulated
|
|
* @dst: - Address of data to be decapsulated
|
|
* @len: - Size of data to be decapsulated
|
|
*
|
|
* Returns zero on success,and negative on error.
|
|
*/
|
|
__weak int blob_decap(u8 *key_mod, u8 *src, u8 *dst, u32 len)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* blob_encap() - Encapsulate the data as a blob
|
|
* @key_mod: - Pointer to key modifier/key
|
|
* @src: - Address of data to be encapsulated
|
|
* @dst: - Address of data to be encapsulated
|
|
* @len: - Size of data to be encapsulated
|
|
*
|
|
* Returns zero on success,and negative on error.
|
|
*/
|
|
__weak int blob_encap(u8 *key_mod, u8 *src, u8 *dst, u32 len)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* do_blob() - Handle the "blob" command-line command
|
|
* @cmdtp: Command data struct pointer
|
|
* @flag: Command flag
|
|
* @argc: Command-line argument count
|
|
* @argv: Array of command-line arguments
|
|
*
|
|
* Returns zero on success, CMD_RET_USAGE in case of misuse and negative
|
|
* on error.
|
|
*/
|
|
static int do_blob(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
|
|
{
|
|
uint32_t key_addr, src_addr, dst_addr, len;
|
|
uint8_t *km_ptr, *src_ptr, *dst_ptr;
|
|
int enc, ret = 0;
|
|
|
|
if (argc != 6)
|
|
return CMD_RET_USAGE;
|
|
|
|
if (!strncmp(argv[1], "enc", 3))
|
|
enc = 1;
|
|
else if (!strncmp(argv[1], "dec", 3))
|
|
enc = 0;
|
|
else
|
|
return CMD_RET_USAGE;
|
|
|
|
src_addr = simple_strtoul(argv[2], NULL, 16);
|
|
dst_addr = simple_strtoul(argv[3], NULL, 16);
|
|
len = simple_strtoul(argv[4], NULL, 16);
|
|
key_addr = simple_strtoul(argv[5], NULL, 16);
|
|
|
|
km_ptr = (uint8_t *)key_addr;
|
|
src_ptr = (uint8_t *)src_addr;
|
|
dst_ptr = (uint8_t *)dst_addr;
|
|
|
|
if (enc)
|
|
ret = blob_encap(km_ptr, src_ptr, dst_ptr, len);
|
|
else
|
|
ret = blob_decap(km_ptr, src_ptr, dst_ptr, len);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/***************************************************/
|
|
static char blob_help_text[] =
|
|
"enc src dst len km - Encapsulate and create blob of data\n"
|
|
" $len bytes long at address $src and\n"
|
|
" store the result at address $dst.\n"
|
|
" $km is the 16 byte key modifier\n"
|
|
" is also required for generation/use as\n"
|
|
" key for cryptographic operation. Key\n"
|
|
" modifier should be 16 byte long.\n"
|
|
"blob dec src dst len km - Decapsulate the blob of data at address\n"
|
|
" $src and store result of $len byte at\n"
|
|
" addr $dst.\n"
|
|
" $km is the 16 byte key modifier\n"
|
|
" is also required for generation/use as\n"
|
|
" key for cryptographic operation. Key\n"
|
|
" modifier should be 16 byte long.\n";
|
|
|
|
U_BOOT_CMD(
|
|
blob, 6, 1, do_blob,
|
|
"Blob encapsulation/decryption",
|
|
blob_help_text
|
|
);
|