wolfBoot-examples/test-app-STM32F4-measured-boot/src/app_stm32f4.c

445 lines
12 KiB
C

/* app_stm32f4.c
*
* Test bare-metal application for reporting measured boot value over UART
*
* Copyright (C) 2021 wolfSSL Inc.
*
* This file is part of wolfBoot.
*
* wolfBoot is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* wolfBoot is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
*/
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include "system.h"
#include "timer.h"
#include "led.h"
#include "hal.h"
#include "wolfboot/wolfboot.h"
#include "spi_flash.h"
#include "spi_drv.h"
#include "spi_tpm.h"
#include "wolftpm/tpm2.h"
#include "wolftpm/tpm2_wrap.h"
static WOLFTPM2_DEV wolftpm_dev;
#define UART1 (0x40011000)
#define UART2 (0x40014400)
#ifndef APP_UART
#define APP_UART UART1
#endif
#define UART_SR (*(volatile uint32_t *)(APP_UART))
#define UART_DR (*(volatile uint32_t *)(APP_UART + 0x04))
#define UART_BRR (*(volatile uint32_t *)(APP_UART + 0x08))
#define UART_CR1 (*(volatile uint32_t *)(APP_UART + 0x0c))
#define UART_CR2 (*(volatile uint32_t *)(APP_UART + 0x10))
#define UART_CR1_UART_ENABLE (1 << 13)
#define UART_CR1_SYMBOL_LEN (1 << 12)
#define UART_CR1_PARITY_ENABLED (1 << 10)
#define UART_CR1_PARITY_ODD (1 << 9)
#define UART_CR1_TX_ENABLE (1 << 3)
#define UART_CR1_RX_ENABLE (1 << 2)
#define UART_CR2_STOPBITS (3 << 12)
#define UART_SR_TX_EMPTY (1 << 7)
#define UART_SR_RX_NOTEMPTY (1 << 5)
#define CLOCK_SPEED (168000000)
#define APB2_CLOCK_ER (*(volatile uint32_t *)(0x40023844))
#define UART1_APB2_CLOCK_ER (1 << 4)
#define UART2_APB2_CLOCK_ER (1 << 17)
#define AHB1_CLOCK_ER (*(volatile uint32_t *)(0x40023830))
#define GPIOA_AHB1_CLOCK_ER (1 << 0)
#define GPIOB_AHB1_CLOCK_ER (1 << 1)
#ifndef GPIOA_BASE
#define GPIOA_BASE 0x48000000
#endif
#define GPIOA_MODE (*(volatile uint32_t *)(GPIOA_BASE + 0x00))
#define GPIOA_AFL (*(volatile uint32_t *)(GPIOA_BASE + 0x20))
#define GPIOA_AFH (*(volatile uint32_t *)(GPIOA_BASE + 0x24))
#ifndef GPIOB_BASE
#define GPIOB_BASE 0x48000400
#endif
#define GPIOB_MODE (*(volatile uint32_t *)(GPIOB_BASE + 0x00))
#define GPIOB_AFL (*(volatile uint32_t *)(GPIOB_BASE + 0x20))
#define GPIOB_AFH (*(volatile uint32_t *)(GPIOB_BASE + 0x24))
#define UART_PIN_AF 7
#define UART1_RX_PIN 7 /* PB7 */
#define UART1_TX_PIN 6 /* PB6 */
#define UART2_RX_PIN 3 /* PA3 */
#define UART2_TX_PIN 2 /* PA2 */
#define MSGSIZE 16
#define PAGESIZE (256)
static uint8_t page[PAGESIZE];
static const char ERR='!';
static const char START='*';
static const char UPDATE='U';
static const char ACK='#';
static uint8_t msg[MSGSIZE];
static const char startString[]="App started";
static const char TPMfailString[]="tpm_init failed";
static const char TPMpcrString[]="Measured Boot PCR is = ";
static const char HEX [16] = {'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'};
volatile uint32_t time_elapsed = 0; /* Used for PWM on LED */
void uart_write(const char c)
{
uint32_t reg;
do {
reg = UART_SR;
} while ((reg & UART_SR_TX_EMPTY) == 0);
UART_DR = c;
}
void uart_write_hex(const char c)
{
uart_write(HEX[(c >> 4) & 0x0F]);
uart_write(HEX[c & 0x0F]);
}
static void uart_pins_setup(void)
{
uint32_t reg;
#if APP_UART == UART1
AHB1_CLOCK_ER |= GPIOB_AHB1_CLOCK_ER;
/* Set mode = AF */
reg = GPIOB_MODE & ~ (0x03 << (UART1_RX_PIN * 2));
GPIOB_MODE = reg | (2 << (UART1_RX_PIN * 2));
reg = GPIOB_MODE & ~ (0x03 << (UART1_TX_PIN * 2));
GPIOB_MODE = reg | (2 << (UART1_TX_PIN * 2));
/* Alternate function: use low pins (6 and 7) */
reg = GPIOB_AFL & ~(0xf << ((UART1_TX_PIN) * 4));
GPIOB_AFL = reg | (UART_PIN_AF << ((UART1_TX_PIN) * 4));
reg = GPIOB_AFL & ~(0xf << ((UART1_RX_PIN) * 4));
GPIOB_AFL = reg | (UART_PIN_AF << ((UART1_RX_PIN) * 4));
#elif APP_UART == UART2
AHB1_CLOCK_ER |= GPIOA_AHB1_CLOCK_ER;
/* Set mode = AF */
reg = GPIOA_MODE & ~ (0x03 << (UART2_RX_PIN * 2));
GPIOA_MODE = reg | (2 << (UART2_RX_PIN * 2));
reg = GPIOA_MODE & ~ (0x03 << (UART2_TX_PIN * 2));
GPIOA_MODE = reg | (2 << (UART2_TX_PIN * 2));
/* Alternate function: use low pins (6 and 7) */
reg = GPIOA_AFL & ~(0xf << ((UART2_TX_PIN) * 4));
GPIOA_AFL = reg | (UART_PIN_AF << ((UART2_TX_PIN) * 4));
reg = GPIOA_AFL & ~(0xf << ((UART2_RX_PIN) * 4));
GPIOA_AFL = reg | (UART_PIN_AF << ((UART2_RX_PIN) * 4));
#else
#error Please configure the UART pins
#endif
}
int uart_setup(uint32_t bitrate, uint8_t data, char parity, uint8_t stop)
{
uint32_t reg;
/* Enable pins and configure for AF7 */
uart_pins_setup();
/* Turn on the device */
#if APP_UART == UART1
APB2_CLOCK_ER |= UART1_APB2_CLOCK_ER;
#elif APP_UART == UART2
APB2_CLOCK_ER |= UART2_APB2_CLOCK_ER;
#endif
/* Configure for TX + RX */
UART_CR1 |= (UART_CR1_TX_ENABLE | UART_CR1_RX_ENABLE);
/* Configure clock */
UART_BRR = CLOCK_SPEED / bitrate;
/* Configure data bits */
if (data == 8)
UART_CR1 &= ~UART_CR1_SYMBOL_LEN;
else
UART_CR1 |= UART_CR1_SYMBOL_LEN;
/* Configure parity */
switch (parity) {
case 'O':
UART_CR1 |= UART_CR1_PARITY_ODD;
/* fall through to enable parity */
case 'E':
UART_CR1 |= UART_CR1_PARITY_ENABLED;
break;
default:
UART_CR1 &= ~(UART_CR1_PARITY_ENABLED | UART_CR1_PARITY_ODD);
}
/* Set stop bits */
reg = UART_CR2 & ~UART_CR2_STOPBITS;
if (stop > 1)
UART_CR2 = reg & (2 << 12);
else
UART_CR2 = reg;
/* Turn on uart */
UART_CR1 |= UART_CR1_UART_ENABLE;
return 0;
}
char uart_read(void)
{
char c;
volatile uint32_t reg;
do {
reg = UART_SR;
} while ((reg & UART_SR_RX_NOTEMPTY) == 0);
c = (char)(UART_DR & 0xff);
return c;
}
static void ack(uint32_t _off)
{
uint8_t *off = (uint8_t *)(&_off);
int i;
uart_write(ACK);
for (i = 0; i < 4; i++) {
uart_write(off[i]);
}
}
static int check(uint8_t *pkt, int size)
{
int i;
uint16_t c = 0;
uint16_t c_rx = *((uint16_t *)(pkt + 2));
uint16_t *p = (uint16_t *)(pkt + 4);
for (i = 0; i < ((size - 4) >> 1); i++)
c += p[i];
if (c == c_rx)
return 0;
return -1;
}
static int app_tpm2_IoCb(TPM2_CTX* ctx, const byte* txBuf, byte* rxBuf,
word16 xferSz, void* userCtx)
{
(void)userCtx;
(void)ctx;
word16 i;
spi_cs_on(SPI_CS_TPM);
XMEMSET(rxBuf, 0, xferSz);
for (i = 0; i < xferSz; i++)
{
spi_write(txBuf[i]);
rxBuf[i] = spi_read();
}
spi_cs_off(SPI_CS_TPM);
/*
printf("\r\nSPI TX: ");
printbin(txBuf, xferSz);
printf("SPI RX: ");
printbin(rxBuf, xferSz);
printf("\r\n");
*/
return 0;
}
static int app_tpm2_init(void)
{
int rc;
WOLFTPM2_CAPS caps;
spi_init(0,0);
/* Init the TPM2 device */
rc = wolfTPM2_Init(&wolftpm_dev, app_tpm2_IoCb, NULL);
if (rc != 0) {
return rc;
}
/* Get device capabilities + options */
rc = wolfTPM2_GetCapabilities(&wolftpm_dev, &caps);
if (rc != 0) {
return rc;
}
return 0;
}
/* Reads out the TPM measurement created by wolfBoot */
static int read_measured_boot(uint8_t* digest)
{
int rc;
PCR_Read_In pcrReadCmd;
PCR_Read_Out pcrReadResp;
XMEMSET(&pcrReadCmd, 0, sizeof(pcrReadCmd));
TPM2_SetupPCRSel(&pcrReadCmd.pcrSelectionIn, TPM_ALG_SHA256, WOLFBOOT_MEASURED_PCR_A);
rc = TPM2_PCR_Read(&pcrReadCmd, &pcrReadResp);
if (rc == TPM_RC_SUCCESS) {
XMEMCPY(digest, pcrReadResp.pcrValues.digests[0].buffer,
pcrReadResp.pcrValues.digests[0].size);
rc = 0;
}
return rc;
}
void main(void)
{
uint32_t tlen = 0;
volatile uint32_t recv_seq;
uint32_t r_total = 0;
uint32_t tot_len = 0;
uint32_t next_seq = 0;
uint32_t version = 0;
uint8_t *v_array = (uint8_t *)&version;
uint8_t boot_measurement[WOLFBOOT_SHA_DIGEST_SIZE];
int i;
memset(page, 0xFF, PAGESIZE);
boot_led_on();
flash_set_waitstates();
clock_config();
led_pwm_setup();
pwm_init(CPU_FREQ, 0);
/* Dim the led by altering the PWM duty-cicle
* in isr_tim2 (timer.c)
*
* Every 50ms, the duty cycle of the PWM connected
* to the blue led increases/decreases making a pulse
* effect.
*/
timer_init(CPU_FREQ, 1, 50);
uart_setup(115200, 8, 'N', 1);
memset(page, 0xFF, PAGESIZE);
asm volatile ("cpsie i");
while(time_elapsed == 0)
WFI();
hal_flash_unlock();
version = wolfBoot_current_firmware_version();
if ((version & 0x01) == 0)
wolfBoot_success();
#ifdef EXT_ENCRYPTED
wolfBoot_set_encrypt_key("0123456789abcdef0123456789abcdef", 32);
#endif
for(i=0; i < sizeof(startString); i++) {
uart_write(startString[i++]);
}
uart_write(START);
for (i = 3; i >= 0; i--) {
uart_write(v_array[i]);
}
if(app_tpm2_init() != 0) {
for(i=0; i < sizeof(TPMfailString); i++) {
uart_write(TPMfailString[i]);
}
}
if(read_measured_boot(boot_measurement) == 0) {
for(i = 0; i < sizeof(TPMpcrString); i++) {
uart_write(TPMpcrString[i]);
}
/* Print the digest of the measurement */
for(i=0; i < sizeof(boot_measurement); i++) {
uart_write_hex(boot_measurement[i]);
}
/* For better view on the UART terminal */
uart_write('\n');
uart_write('\r');
}
while (1) {
r_total = 0;
do {
while(r_total < 2) {
msg[r_total++] = uart_read();
if ((r_total == 2) && ((msg[0] != 0xA5) || msg[1] != 0x5A)) {
r_total = 0;
continue;
}
}
msg[r_total++] = uart_read();
if ((tot_len == 0) && r_total == 2 + sizeof(uint32_t))
break;
if ((r_total > 8) && (tot_len <= ((r_total - 8) + next_seq)))
break;
} while (r_total < MSGSIZE);
if (tot_len == 0) {
tlen = msg[2] + (msg[3] << 8) + (msg[4] << 16) + (msg[5] << 24);
if (tlen > WOLFBOOT_PARTITION_SIZE - 8) {
uart_write(ERR);
uart_write(ERR);
uart_write(ERR);
uart_write(ERR);
uart_write(START);
recv_seq = 0;
tot_len = 0;
continue;
}
tot_len = tlen;
ack(0);
continue;
}
if (check(msg, r_total) < 0) {
ack(next_seq);
continue;
}
recv_seq = msg[4] + (msg[5] << 8) + (msg[6] << 16) + (msg[7] << 24);
if (recv_seq == next_seq)
{
int psize = r_total - 8;
int page_idx = recv_seq % PAGESIZE;
memcpy(&page[recv_seq % PAGESIZE], msg + 8, psize);
page_idx += psize;
if ((page_idx == PAGESIZE) || (next_seq + psize >= tot_len)) {
uint32_t dst = (WOLFBOOT_PARTITION_UPDATE_ADDRESS + recv_seq + psize) - page_idx;
if ((dst % WOLFBOOT_SECTOR_SIZE) == 0) {
hal_flash_erase(dst, WOLFBOOT_SECTOR_SIZE);
}
hal_flash_write(dst, page, PAGESIZE);
memset(page, 0xFF, PAGESIZE);
}
next_seq += psize;
}
ack(next_seq);
if (next_seq >= tot_len) {
/* Update complete */
spi_flash_probe();
wolfBoot_update_trigger();
spi_release();
hal_flash_lock();
break;
}
}
/* Wait for reboot */
while(1)
;
}