/* * 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 <libopencm3/cm3/mpu.h> #include <libopencm3/cm3/nvic.h> #include <libopencm3/cm3/scb.h> #include <libopencm3/stm32/gpio.h> #include <libopencm3/stm32/rcc.h> #include <libopencm3/stm32/rng.h> #include <libopencm3/stm32/spi.h> #include "layout.h" #include "rng.h" #include "util.h" uint32_t __stack_chk_guard; static inline void __attribute__((noreturn)) fault_handler(const char *line1) { layoutDialog(&bmp_icon_error, NULL, NULL, NULL, line1, "detected.", NULL, "Please unplug", "the device.", NULL); shutdown(); } void __attribute__((noreturn)) __stack_chk_fail(void) { fault_handler("Stack smashing"); } void nmi_handler(void) { // Clock Security System triggered NMI if ((RCC_CIR & RCC_CIR_CSSF) != 0) { fault_handler("Clock instability"); } } void hard_fault_handler(void) { fault_handler("Hard fault"); } void mem_manage_handler(void) { fault_handler("Memory fault"); } void setup(void) { // set SCB_CCR STKALIGN bit to make sure 8-byte stack alignment on exception // entry is in effect. This is not strictly necessary for the current Trezor // system. This is here to comply with guidance from section 3.3.3 "Binary // compatibility with other Cortex processors" of the ARM Cortex-M3 Processor // Technical Reference Manual. According to section 4.4.2 and 4.4.7 of the // "STM32F10xxx/20xxx/21xxx/L1xxxx Cortex-M3 programming manual", STM32F2 // series MCUs are r2p0 and always have this bit set on reset already. SCB_CCR |= SCB_CCR_STKALIGN; // setup clock struct rcc_clock_scale clock = rcc_hse_8mhz_3v3[RCC_CLOCK_3V3_120MHZ]; rcc_clock_setup_hse_3v3(&clock); // enable GPIO clock - A (oled), B(oled), C (buttons) rcc_periph_clock_enable(RCC_GPIOA); rcc_periph_clock_enable(RCC_GPIOB); rcc_periph_clock_enable(RCC_GPIOC); // enable SPI clock rcc_periph_clock_enable(RCC_SPI1); // enable RNG rcc_periph_clock_enable(RCC_RNG); RNG_CR |= RNG_CR_RNGEN; // to be extra careful and heed the STM32F205xx Reference manual, // Section 20.3.1 we don't use the first random number generated after setting // the RNGEN bit in setup random32(); // enable CSS (Clock Security System) RCC_CR |= RCC_CR_CSSON; // set GPIO for buttons gpio_mode_setup(GPIOC, GPIO_MODE_INPUT, GPIO_PUPD_PULLUP, GPIO2 | GPIO5); // set GPIO for OLED display gpio_mode_setup(GPIOA, GPIO_MODE_OUTPUT, GPIO_PUPD_NONE, GPIO4); gpio_mode_setup(GPIOB, GPIO_MODE_OUTPUT, GPIO_PUPD_NONE, GPIO0 | GPIO1); // enable SPI 1 for OLED display gpio_mode_setup(GPIOA, GPIO_MODE_AF, GPIO_PUPD_NONE, GPIO5 | GPIO7); gpio_set_af(GPIOA, GPIO_AF5, GPIO5 | GPIO7); // spi_disable_crc(SPI1); spi_init_master( SPI1, SPI_CR1_BAUDRATE_FPCLK_DIV_8, SPI_CR1_CPOL_CLK_TO_0_WHEN_IDLE, SPI_CR1_CPHA_CLK_TRANSITION_1, SPI_CR1_DFF_8BIT, SPI_CR1_MSBFIRST); spi_enable_ss_output(SPI1); // spi_enable_software_slave_management(SPI1); // spi_set_nss_high(SPI1); // spi_clear_mode_fault(SPI1); spi_enable(SPI1); // enable OTG_FS gpio_mode_setup(GPIOA, GPIO_MODE_AF, GPIO_PUPD_PULLUP, GPIO10); gpio_mode_setup(GPIOA, GPIO_MODE_AF, GPIO_PUPD_NONE, GPIO11 | GPIO12); gpio_set_af(GPIOA, GPIO_AF10, GPIO10 | GPIO11 | GPIO12); // enable OTG FS clock rcc_periph_clock_enable(RCC_OTGFS); // clear USB OTG_FS peripheral dedicated RAM memset_reg((void *)0x50020000, (void *)0x50020500, 0); } void setupApp(void) { // for completeness, disable RNG peripheral interrupts for old bootloaders // that had enabled them in RNG control register (the RNG interrupt was never // enabled in the NVIC) RNG_CR &= ~RNG_CR_IE; // the static variables in random32 are separate between the bootloader and // firmware. therefore, they need to be initialized here so that we can be // sure to avoid dupes. this is to try to comply with STM32F205xx Reference // manual - Section 20.3.1: "Each subsequent generated random number has to be // compared with the previously generated number. The test fails if any two // compared numbers are equal (continuous random number generator test)." random32(); // enable CSS (Clock Security System) RCC_CR |= RCC_CR_CSSON; // hotfix for old bootloader gpio_mode_setup(GPIOA, GPIO_MODE_INPUT, GPIO_PUPD_NONE, GPIO9); spi_init_master( SPI1, SPI_CR1_BAUDRATE_FPCLK_DIV_8, SPI_CR1_CPOL_CLK_TO_0_WHEN_IDLE, SPI_CR1_CPHA_CLK_TRANSITION_1, SPI_CR1_DFF_8BIT, SPI_CR1_MSBFIRST); gpio_mode_setup(GPIOA, GPIO_MODE_AF, GPIO_PUPD_PULLUP, GPIO10); gpio_set_af(GPIOA, GPIO_AF10, GPIO10); } #define MPU_RASR_SIZE_32B (0x04UL << MPU_RASR_SIZE_LSB) #define MPU_RASR_SIZE_1KB (0x09UL << MPU_RASR_SIZE_LSB) #define MPU_RASR_SIZE_4KB (0x0BUL << MPU_RASR_SIZE_LSB) #define MPU_RASR_SIZE_8KB (0x0CUL << MPU_RASR_SIZE_LSB) #define MPU_RASR_SIZE_16KB (0x0DUL << MPU_RASR_SIZE_LSB) #define MPU_RASR_SIZE_32KB (0x0EUL << MPU_RASR_SIZE_LSB) #define MPU_RASR_SIZE_64KB (0x0FUL << MPU_RASR_SIZE_LSB) #define MPU_RASR_SIZE_128KB (0x10UL << MPU_RASR_SIZE_LSB) #define MPU_RASR_SIZE_256KB (0x11UL << MPU_RASR_SIZE_LSB) #define MPU_RASR_SIZE_512KB (0x12UL << MPU_RASR_SIZE_LSB) #define MPU_RASR_SIZE_1MB (0x13UL << MPU_RASR_SIZE_LSB) #define MPU_RASR_SIZE_512MB (0x1CUL << MPU_RASR_SIZE_LSB) #define MPU_RASR_SIZE_4GB (0x1FUL << MPU_RASR_SIZE_LSB) // http://infocenter.arm.com/help/topic/com.arm.doc.dui0552a/BABDJJGF.html #define MPU_RASR_ATTR_FLASH (MPU_RASR_ATTR_C) #define MPU_RASR_ATTR_SRAM (MPU_RASR_ATTR_C | MPU_RASR_ATTR_S) #define MPU_RASR_ATTR_PERIPH (MPU_RASR_ATTR_B | MPU_RASR_ATTR_S) #define FLASH_BASE (0x08000000U) #define SRAM_BASE (0x20000000U) void mpu_config_off(void) { // Disable MPU MPU_CTRL = 0; __asm__ volatile("dsb"); __asm__ volatile("isb"); } void mpu_config_bootloader(void) { // Disable MPU MPU_CTRL = 0; // Note: later entries overwrite previous ones // Everything (0x00000000 - 0xFFFFFFFF, 4 GiB, read-write) MPU_RBAR = 0 | MPU_RBAR_VALID | (0 << MPU_RBAR_REGION_LSB); MPU_RASR = MPU_RASR_ENABLE | MPU_RASR_ATTR_FLASH | MPU_RASR_SIZE_4GB | MPU_RASR_ATTR_AP_PRW_URW; // Flash (0x8007FE0 - 0x08007FFF, 32 B, no-access) MPU_RBAR = (FLASH_BASE + 0x7FE0) | MPU_RBAR_VALID | (1 << MPU_RBAR_REGION_LSB); MPU_RASR = MPU_RASR_ENABLE | MPU_RASR_ATTR_FLASH | MPU_RASR_SIZE_32B | MPU_RASR_ATTR_AP_PNO_UNO; // SRAM (0x20000000 - 0x2001FFFF, read-write, execute never) MPU_RBAR = SRAM_BASE | MPU_RBAR_VALID | (2 << MPU_RBAR_REGION_LSB); MPU_RASR = MPU_RASR_ENABLE | MPU_RASR_ATTR_SRAM | MPU_RASR_SIZE_128KB | MPU_RASR_ATTR_AP_PRW_URW | MPU_RASR_ATTR_XN; // Peripherals (0x40000000 - 0x4001FFFF, read-write, execute never) MPU_RBAR = PERIPH_BASE | MPU_RBAR_VALID | (3 << MPU_RBAR_REGION_LSB); MPU_RASR = MPU_RASR_ENABLE | MPU_RASR_ATTR_PERIPH | MPU_RASR_SIZE_128KB | MPU_RASR_ATTR_AP_PRW_URW | MPU_RASR_ATTR_XN; // Peripherals (0x40020000 - 0x40023FFF, read-write, execute never) MPU_RBAR = 0x40020000 | MPU_RBAR_VALID | (4 << MPU_RBAR_REGION_LSB); MPU_RASR = MPU_RASR_ENABLE | MPU_RASR_ATTR_PERIPH | MPU_RASR_SIZE_16KB | MPU_RASR_ATTR_AP_PRW_URW | MPU_RASR_ATTR_XN; // Don't enable DMA controller access // Peripherals (0x50000000 - 0x5007ffff, read-write, execute never) MPU_RBAR = 0x50000000 | MPU_RBAR_VALID | (5 << MPU_RBAR_REGION_LSB); MPU_RASR = MPU_RASR_ENABLE | MPU_RASR_ATTR_PERIPH | MPU_RASR_SIZE_512KB | MPU_RASR_ATTR_AP_PRW_URW | MPU_RASR_ATTR_XN; // Enable MPU MPU_CTRL = MPU_CTRL_ENABLE | MPU_CTRL_HFNMIENA; // Enable memory fault handler SCB_SHCSR |= SCB_SHCSR_MEMFAULTENA; __asm__ volatile("dsb"); __asm__ volatile("isb"); } // Never use in bootloader! Disables access to PPB (including MPU, NVIC, SCB) void mpu_config_firmware(void) { #if MEMORY_PROTECT // Disable MPU MPU_CTRL = 0; // Note: later entries overwrite previous ones // Flash (0x08000000 - 0x0807FFFF, 1 MiB, read-only) MPU_RBAR = FLASH_BASE | MPU_RBAR_VALID | (0 << MPU_RBAR_REGION_LSB); MPU_RASR = MPU_RASR_ENABLE | MPU_RASR_ATTR_FLASH | MPU_RASR_SIZE_1MB | MPU_RASR_ATTR_AP_PRO_URO; // Metadata in Flash is read-write when unlocked // (0x08008000 - 0x0800FFFF, 32 KiB, read-write, execute never) MPU_RBAR = (FLASH_BASE + 0x8000) | MPU_RBAR_VALID | (1 << MPU_RBAR_REGION_LSB); MPU_RASR = MPU_RASR_ENABLE | MPU_RASR_ATTR_FLASH | MPU_RASR_SIZE_32KB | MPU_RASR_ATTR_AP_PRW_URW | MPU_RASR_ATTR_XN; // SRAM (0x20000000 - 0x2001FFFF, read-write, execute never) MPU_RBAR = SRAM_BASE | MPU_RBAR_VALID | (2 << MPU_RBAR_REGION_LSB); MPU_RASR = MPU_RASR_ENABLE | MPU_RASR_ATTR_SRAM | MPU_RASR_SIZE_128KB | MPU_RASR_ATTR_AP_PRW_URW | MPU_RASR_ATTR_XN; // Peripherals (0x40000000 - 0x4001FFFF, read-write, execute never) MPU_RBAR = PERIPH_BASE | MPU_RBAR_VALID | (3 << MPU_RBAR_REGION_LSB); MPU_RASR = MPU_RASR_ENABLE | MPU_RASR_ATTR_PERIPH | MPU_RASR_SIZE_128KB | MPU_RASR_ATTR_AP_PRW_URW | MPU_RASR_ATTR_XN; // Peripherals (0x40020000 - 0x40023FFF, read-write, execute never) MPU_RBAR = 0x40020000 | MPU_RBAR_VALID | (4 << MPU_RBAR_REGION_LSB); MPU_RASR = MPU_RASR_ENABLE | MPU_RASR_ATTR_PERIPH | MPU_RASR_SIZE_16KB | MPU_RASR_ATTR_AP_PRW_URW | MPU_RASR_ATTR_XN; // Flash controller is protected // (0x40023C00 - 0x40023FFF, privileged read-write, user no, execute never) MPU_RBAR = 0x40023c00 | MPU_RBAR_VALID | (5 << MPU_RBAR_REGION_LSB); MPU_RASR = MPU_RASR_ENABLE | MPU_RASR_ATTR_PERIPH | MPU_RASR_SIZE_1KB | MPU_RASR_ATTR_AP_PRW_UNO | MPU_RASR_ATTR_XN; // Don't enable DMA controller access // Peripherals (0x50000000 - 0x5007ffff, read-write, execute never) MPU_RBAR = 0x50000000 | MPU_RBAR_VALID | (6 << MPU_RBAR_REGION_LSB); MPU_RASR = MPU_RASR_ENABLE | MPU_RASR_ATTR_PERIPH | MPU_RASR_SIZE_512KB | MPU_RASR_ATTR_AP_PRW_URW | MPU_RASR_ATTR_XN; // SYSCFG_* registers are disabled // (0x40013800 - 0x40013BFF, read-only, execute never) MPU_RBAR = 0x40013800 | MPU_RBAR_VALID | (7 << MPU_RBAR_REGION_LSB); MPU_RASR = MPU_RASR_ENABLE | MPU_RASR_ATTR_PERIPH | MPU_RASR_SIZE_1KB | MPU_RASR_ATTR_AP_PRO_URO | MPU_RASR_ATTR_XN; // Enable MPU MPU_CTRL = MPU_CTRL_ENABLE | MPU_CTRL_HFNMIENA; // Enable memory fault handler SCB_SHCSR |= SCB_SHCSR_MEMFAULTENA; __asm__ volatile("dsb"); __asm__ volatile("isb"); // Switch to unprivileged software execution to prevent access to MPU set_mode_unprivileged(); #endif }