/* * This file is part of the Trezor project, https://trezor.io/ * * Copyright (C) 2014 Pavol Rusnak <stick@satoshilabs.com> * * This library is free software: you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This library 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 Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with this library. If not, see <http://www.gnu.org/licenses/>. */ #include <string.h> #include <libopencm3/cm3/scb.h> #include <libopencm3/stm32/gpio.h> #include <libopencm3/stm32/rcc.h> #include "bootloader.h" #include "buttons.h" #include "compiler_traits.h" #include "layout.h" #include "memory.h" #include "oled.h" #include "rng.h" #include "setup.h" #include "signatures.h" #include "supervise.h" #include "usb.h" #include "util.h" void layoutFirmwareFingerprint(const uint8_t *hash) { char str[4][17] = {0}; for (int i = 0; i < 4; i++) { data2hex(hash + i * 8, 8, str[i]); } layoutDialog(&bmp_icon_question, "Abort", "Continue", "Compare fingerprints", str[0], str[1], str[2], str[3], NULL, NULL); } bool get_button_response(void) { do { delay(100000); buttonUpdate(); } while (!button.YesUp && !button.NoUp); return button.YesUp; } void show_halt(const char *line1, const char *line2) { layoutDialog(&bmp_icon_error, NULL, NULL, NULL, line1, line2, NULL, "Unplug your Trezor,", "reinstall firmware.", NULL); shutdown(); } void show_unplug(const char *line1, const char *line2) { layoutDialog(&bmp_icon_ok, NULL, NULL, NULL, line1, line2, NULL, "You may now", "unplug your Trezor.", NULL); } static void show_unofficial_warning(const uint8_t *hash) { layoutDialog(&bmp_icon_warning, "Abort", "I'll take the risk", NULL, "WARNING!", NULL, "Unofficial firmware", "detected.", NULL, NULL); bool but = get_button_response(); if (!but) { // no button was pressed -> halt show_halt("Unofficial firmware", "aborted."); } layoutFirmwareFingerprint(hash); but = get_button_response(); if (!but) { // no button was pressed -> halt show_halt("Unofficial firmware", "aborted."); } // everything is OK, user pressed 2x Continue -> continue program } static void __attribute__((noreturn)) load_app(int signed_firmware) { // zero out SRAM memset_reg(_ram_start, _ram_end, 0); jump_to_firmware((const vector_table_t *)FLASH_PTR(FLASH_APP_START), signed_firmware); } static void bootloader_loop(void) { oledClear(); oledDrawBitmap(0, 0, &bmp_logo64_half); oledDrawBitmapFlip(24, 0, &bmp_logo64_half); if (firmware_present_new()) { oledDrawStringCenter(90, 10, "Trezor", FONT_STANDARD); oledDrawStringCenter(90, 30, "Bootloader", FONT_STANDARD); oledDrawStringCenter(90, 50, VERSTR(VERSION_MAJOR) "." VERSTR( VERSION_MINOR) "." VERSTR(VERSION_PATCH), FONT_STANDARD); } else { oledDrawStringCenter(90, 10, "Welcome!", FONT_STANDARD); oledDrawStringCenter(90, 30, "Please visit", FONT_STANDARD); oledDrawStringCenter(90, 50, "trezor.io/start", FONT_STANDARD); } oledRefresh(); usbLoop(); } int main(void) { // grab "stay in bootloader" flag as soon as possible register uint32_t r11 __asm__("r11"); volatile uint32_t stay_in_bootloader_flag = r11; #ifndef APPVER setup(); #endif __stack_chk_guard = random32(); // this supports compiler provided // unpredictable stack protection checks #ifndef APPVER memory_protect(); oledInit(); #endif mpu_config_bootloader(); if (stay_in_bootloader_flag == STAY_IN_BOOTLOADER_FLAG) { goto bootloader_loop_start; } #ifndef APPVER bool left_pressed = (buttonRead() & BTN_PIN_NO) == 0; if (firmware_present_new() && !left_pressed) { oledClear(); oledDrawBitmap(40, 0, &bmp_logo64_empty_half); oledDrawBitmapFlip(40 + 24, 0, &bmp_logo64_empty_half); oledRefresh(); const image_header *hdr = (const image_header *)FLASH_PTR(FLASH_FWHEADER_START); uint8_t fingerprint[32] = {0}; int signed_firmware = signatures_new_ok(hdr, fingerprint); if (SIG_OK != signed_firmware) { show_unofficial_warning(fingerprint); } if (SIG_OK != check_firmware_hashes(hdr)) { show_halt("Broken firmware", "detected."); } mpu_config_off(); load_app(signed_firmware); } #endif bootloader_loop_start: bootloader_loop(); return 0; }