/*
* mgmt-masterkey.c
* ----------------
* Masterkey CLI functions.
*
* Copyright (c) 2016, NORDUnet A/S All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of the NORDUnet nor the names of its contributors may
* be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
* IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/* Rename both CMSIS HAL_OK and libhal HAL_OK to disambiguate */
#define HAL_OK CMSIS_HAL_OK
#include "stm-init.h"
#include "stm-uart.h"
#include "mgmt-cli.h"
#include "mgmt-masterkey.h"
#undef HAL_OK
#define LIBHAL_OK HAL_OK
#include <hal.h>
#include <masterkey.h>
#undef HAL_OK
#include <stdlib.h>
#define KEK_LENGTH (256 / 8)
static char * _status2str(const hal_error_t status)
{
switch (status) {
case LIBHAL_OK:
return (char *) "Set";
case HAL_ERROR_MASTERKEY_NOT_SET:
return (char *) "Not set";
default:
return (char *) "Unknown";
}
}
static int _parse_hex_groups(uint8_t *buf, size_t len, char *argv[], int argc)
{
int i;
uint32_t *dst = (uint32_t *) buf;
uint32_t *end = (uint32_t *) buf + len - 1;
char *err_ptr = NULL;
if (! argc) return 0;
for (i = 0; i < argc; i++) {
if (dst >= end) return -1;
*dst++ = strtoul(argv[i], &err_ptr, 16);
if (*err_ptr) return -2;
}
return 1;
}
static int cmd_masterkey_status(struct cli_def *cli, const char *command, char *argv[], int argc)
{
hal_error_t status;
cli_print(cli, "Status of master key:\n");
status = masterkey_volatile_read(NULL, 0);
cli_print(cli, " volatile: %s / %s", _status2str(status), hal_error_string(status));
status = masterkey_flash_read(NULL, 0);
cli_print(cli, " flash: %s / %s", _status2str(status), hal_error_string(status));
return CLI_OK;
}
static int _masterkey_set(struct cli_def *cli, char *argv[], int argc,
char *label, hal_error_t (*writer)(uint8_t *, size_t))
{
uint8_t buf[KEK_LENGTH] = {0};
hal_error_t err;
int i;
if (argc == 0) {
/* fill master key with yummy randomness */
if ((err = hal_get_random(NULL, buf, sizeof(buf))) != LIBHAL_OK) {
cli_print(cli, "Error getting random key: %s", hal_error_string(err));
return CLI_ERROR;
}
cli_print(cli, "Random key:\n");
uart_send_hexdump(STM_UART_MGMT, buf, 0, sizeof(buf) - 1);
cli_print(cli, "\n");
}
else {
if ((i = _parse_hex_groups(&buf[0], sizeof(buf), argv, argc)) != 1) {
cli_print(cli, "Failed parsing master key, expected up to 8 groups of 32-bit hex chars (%i)", i);
return CLI_ERROR;
}
cli_print(cli, "Parsed key:\n");
uart_send_hexdump(STM_UART_MGMT, buf, 0, sizeof(buf) - 1);
cli_print(cli, "\n");
}
if ((err = writer(buf, sizeof(buf))) == LIBHAL_OK) {
cli_print(cli, "Master key set in %s memory", label);
} else {
cli_print(cli, "Failed writing key to %s memory: %s", label, hal_error_string(err));
}
return CLI_OK;
}
static int cmd_masterkey_set(struct cli_def *cli, const char *command, char *argv[], int argc)
{
return _masterkey_set(cli, argv, argc, "volatile", masterkey_volatile_write);
}
static int cmd_masterkey_erase(struct cli_def *cli, const char *command, char *argv[], int argc)
{
hal_error_t err;
if ((err = masterkey_volatile_erase(KEK_LENGTH)) == LIBHAL_OK) {
cli_print(cli, "Erased master key from volatile memory");
} else {
cli_print(cli, "Failed erasing master key from volatile memory: %s", hal_error_string(err));
}
return CLI_OK;
}
static int cmd_masterkey_unsecure_set(struct cli_def *cli, const char *command, char *argv[], int argc)
{
return _masterkey_set(cli, argv, argc, "flash", masterkey_flash_write);
}
static int cmd_masterkey_unsecure_erase(struct cli_def *cli, const char *command, char *argv[], int argc)
{
hal_error_t err;
if ((err = masterkey_flash_erase(KEK_LENGTH)) == LIBHAL_OK) {
cli_print(cli, "Erased unsecure master key from flash");
} else {
cli_print(cli, "Failed erasing unsecure master key from flash: %s", hal_error_string(err));
}
return CLI_OK;
}
void configure_cli_masterkey(struct cli_def *cli)
{
/* masterkey */
cli_command_root(masterkey);
/* masterkey status */
cli_command_node(masterkey, status, "Show status of master key in RAM/flash");
/* masterkey set */
cli_command_node(masterkey, set, "Set the master key in the volatile Master Key Memory");
/* masterkey erase */
cli_command_node(masterkey, erase, "Erase the master key from the volatile Master Key Memory");
cli_command_branch(masterkey, unsecure);
/* masterkey unsecure set */
cli_command_node(masterkey_unsecure, set, "Set master key in unprotected flash memory (if unsure, DON'T)");
/* masterkey unsecure erase */
cli_command_node(masterkey_unsecure, erase, "Erase master key from unprotected flash memory");
}