refactor(core/embed): extract hw entropy logic to its own module

[no changelog]

core/embed/extmod/modtrezorconfig/modtrezorconfig.c

@@ -28,6 +28,7 @@
 #include "embed/extmod/trezorobj.h"
 
 #include "common.h"
+#include "entropy.h"
 #include "memzero.h"
 #include "storage.h"
 
@@ -55,13 +56,16 @@ static secbool wrapped_ui_wait_callback(uint32_t wait, uint32_t progress,
 ///     called from this module!
 ///     """
 STATIC mp_obj_t mod_trezorconfig_init(size_t n_args, const mp_obj_t *args) {
+  uint8_t entropy_data[HW_ENTROPY_LEN];
+  entropy_get(entropy_data);
+
   if (n_args > 0) {
     MP_STATE_VM(trezorconfig_ui_wait_callback) = args[0];
-    storage_init(wrapped_ui_wait_callback, HW_ENTROPY_DATA, HW_ENTROPY_LEN);
+    storage_init(wrapped_ui_wait_callback, entropy_data, HW_ENTROPY_LEN);
   } else {
-    storage_init(NULL, HW_ENTROPY_DATA, HW_ENTROPY_LEN);
+    storage_init(NULL, entropy_data, HW_ENTROPY_LEN);
   }
-  memzero(HW_ENTROPY_DATA, sizeof(HW_ENTROPY_DATA));
+  memzero(entropy_data, sizeof(entropy_data));
   return mp_const_none;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mod_trezorconfig_init_obj, 0, 1,

core/embed/firmware/main.c

@@ -41,6 +41,7 @@
 #include "common.h"
 #include "compiler_traits.h"
 #include "display.h"
+#include "entropy.h"
 #include "fault_handlers.h"
 #include "flash.h"
 #include "image.h"
@@ -179,7 +180,7 @@ int main(void) {
 
   mpu_config_firmware_initial();
 
-  collect_hw_entropy();
+  entropy_init();
 
 #if PRODUCTION || BOOTLOADER_QA
   check_and_replace_bootloader();

core/embed/rust/build.rs

@@ -306,8 +306,9 @@ fn generate_trezorhal_bindings() {
         // model
         .allowlist_var("MODEL_INTERNAL_NAME")
         .allowlist_var("MODEL_FULL_NAME")
-        // common
-        .allowlist_var("HW_ENTROPY_DATA")
+        // entropy
+        .allowlist_var("HW_ENTROPY_LEN")
+        .allowlist_function("entropy_get")
         // secbool
         .allowlist_type("secbool")
         .must_use_type("secbool")

core/embed/rust/src/trezorhal/storage.rs

@@ -97,10 +97,13 @@ pub type StorageResult<T> = Result<T, StorageError>;
 /// This function must be called before any other storage function.
 pub fn init() {
     unsafe {
+        let mut entropy_data: [u8; ffi::HW_ENTROPY_LEN as usize] =
+            [0; ffi::HW_ENTROPY_LEN as usize];
+        ffi::entropy_get(entropy_data.as_mut_ptr());
         ffi::storage_init(
             Some(callback_wrapper),
-            ffi::HW_ENTROPY_DATA.as_ptr(),
-            ffi::HW_ENTROPY_DATA.len() as u16,
+            entropy_data.as_ptr(),
+            entropy_data.len() as u16,
         );
     }
 }

core/embed/rust/trezorhal.h

@@ -7,6 +7,7 @@
 #include "display_draw.h"
 #include "dma2d.h"
 #include "dma2d_bitblt.h"
+#include "entropy.h"
 #include "flash.h"
 #include "fonts/fonts.h"
 #include "gfx_bitblt.h"

core/embed/trezorhal/common.h

@@ -58,10 +58,6 @@ void hal_delay(uint32_t ms);
 uint32_t hal_ticks_ms();
 void hal_delay_us(uint16_t delay_us);
 
-void collect_hw_entropy(void);
-#define HW_ENTROPY_LEN (12 + 32)
-extern uint8_t HW_ENTROPY_DATA[HW_ENTROPY_LEN];
-
 // Invalidates firmware on the device
 // Note: only works when write access to firmware area is enabled by MPU
 void invalidate_firmware(void);

core/embed/trezorhal/entropy.h

@@ -0,0 +1,31 @@
+/*
+ * This file is part of the Trezor project, https://trezor.io/
+ *
+ * Copyright (c) SatoshiLabs
+ *
+ * This program 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef TREZORHAL_ENTROPY_H
+#define TREZORHAL_ENTROPY_H
+
+#include <stdint.h>
+
+void entropy_init(void);
+
+#define HW_ENTROPY_LEN (12 + 32)
+
+void entropy_get(uint8_t *buf);
+
+#endif

core/embed/trezorhal/stm32f4/common.c

@@ -91,32 +91,6 @@ void __attribute__((noreturn)) __stack_chk_fail(void) {
   error_shutdown("(SS)");
 }
 
-uint8_t HW_ENTROPY_DATA[HW_ENTROPY_LEN];
-
-void collect_hw_entropy(void) {
-  // collect entropy from UUID
-  uint32_t w = LL_GetUID_Word0();
-  memcpy(HW_ENTROPY_DATA, &w, 4);
-  w = LL_GetUID_Word1();
-  memcpy(HW_ENTROPY_DATA + 4, &w, 4);
-  w = LL_GetUID_Word2();
-  memcpy(HW_ENTROPY_DATA + 8, &w, 4);
-
-  // set entropy in the OTP randomness block
-  if (secfalse == flash_otp_is_locked(FLASH_OTP_BLOCK_RANDOMNESS)) {
-    uint8_t entropy[FLASH_OTP_BLOCK_SIZE];
-    random_buffer(entropy, FLASH_OTP_BLOCK_SIZE);
-    ensure(flash_otp_write(FLASH_OTP_BLOCK_RANDOMNESS, 0, entropy,
-                           FLASH_OTP_BLOCK_SIZE),
-           NULL);
-    ensure(flash_otp_lock(FLASH_OTP_BLOCK_RANDOMNESS), NULL);
-  }
-  // collect entropy from OTP randomness block
-  ensure(flash_otp_read(FLASH_OTP_BLOCK_RANDOMNESS, 0, HW_ENTROPY_DATA + 12,
-                        FLASH_OTP_BLOCK_SIZE),
-         NULL);
-}
-
 void invalidate_firmware(void) {
   // erase start of the firmware (metadata) -> invalidate FW
   ensure(flash_unlock_write(), NULL);

core/embed/trezorhal/stm32f4/entropy.c

@@ -0,0 +1,55 @@
+/*
+ * This file is part of the Trezor project, https://trezor.io/
+ *
+ * Copyright (c) SatoshiLabs
+ *
+ * This program 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "entropy.h"
+
+#include "entropy.h"
+#include "flash_otp.h"
+#include "model.h"
+#include "rand.h"
+
+#include "stm32f4xx_ll_utils.h"
+
+static uint8_t g_hw_entropy[HW_ENTROPY_LEN];
+
+void entropy_init(void) {
+  // collect entropy from UUID
+  uint32_t w = LL_GetUID_Word0();
+  memcpy(g_hw_entropy, &w, 4);
+  w = LL_GetUID_Word1();
+  memcpy(g_hw_entropy + 4, &w, 4);
+  w = LL_GetUID_Word2();
+  memcpy(g_hw_entropy + 8, &w, 4);
+
+  // set entropy in the OTP randomness block
+  if (secfalse == flash_otp_is_locked(FLASH_OTP_BLOCK_RANDOMNESS)) {
+    uint8_t entropy[FLASH_OTP_BLOCK_SIZE];
+    random_buffer(entropy, FLASH_OTP_BLOCK_SIZE);
+    ensure(flash_otp_write(FLASH_OTP_BLOCK_RANDOMNESS, 0, entropy,
+                           FLASH_OTP_BLOCK_SIZE),
+           NULL);
+    ensure(flash_otp_lock(FLASH_OTP_BLOCK_RANDOMNESS), NULL);
+  }
+  // collect entropy from OTP randomness block
+  ensure(flash_otp_read(FLASH_OTP_BLOCK_RANDOMNESS, 0, g_hw_entropy + 12,
+                        FLASH_OTP_BLOCK_SIZE),
+         NULL);
+}
+
+void entropy_get(uint8_t *buf) { memcpy(buf, g_hw_entropy, HW_ENTROPY_LEN); }

core/embed/trezorhal/stm32u5/common.c

@@ -75,32 +75,6 @@ void __attribute__((noreturn)) __stack_chk_fail(void) {
   error_shutdown("(SS)");
 }
 
-uint8_t HW_ENTROPY_DATA[HW_ENTROPY_LEN];
-
-void collect_hw_entropy(void) {
-  // collect entropy from UUID
-  uint32_t w = LL_GetUID_Word0();
-  memcpy(HW_ENTROPY_DATA, &w, 4);
-  w = LL_GetUID_Word1();
-  memcpy(HW_ENTROPY_DATA + 4, &w, 4);
-  w = LL_GetUID_Word2();
-  memcpy(HW_ENTROPY_DATA + 8, &w, 4);
-
-  // set entropy in the OTP randomness block
-  if (secfalse == flash_otp_is_locked(FLASH_OTP_BLOCK_RANDOMNESS)) {
-    uint8_t entropy[FLASH_OTP_BLOCK_SIZE];
-    random_buffer(entropy, FLASH_OTP_BLOCK_SIZE);
-    ensure(flash_otp_write(FLASH_OTP_BLOCK_RANDOMNESS, 0, entropy,
-                           FLASH_OTP_BLOCK_SIZE),
-           NULL);
-    // ensure(flash_otp_lock(FLASH_OTP_BLOCK_RANDOMNESS), NULL);
-  }
-  // collect entropy from OTP randomness block
-  ensure(flash_otp_read(FLASH_OTP_BLOCK_RANDOMNESS, 0, HW_ENTROPY_DATA + 12,
-                        FLASH_OTP_BLOCK_SIZE),
-         NULL);
-}
-
 void invalidate_firmware(void) {
   // on stm32u5, we need to disable the instruction cache before erasing the
   // firmware - otherwise, the write check will fail

core/embed/trezorhal/stm32u5/entropy.c

@@ -0,0 +1,55 @@
+/*
+ * This file is part of the Trezor project, https://trezor.io/
+ *
+ * Copyright (c) SatoshiLabs
+ *
+ * This program 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <string.h>
+
+#include "entropy.h"
+#include "flash_otp.h"
+#include "model.h"
+#include "rand.h"
+
+#include "stm32u5xx_ll_utils.h"
+
+static uint8_t g_hw_entropy[HW_ENTROPY_LEN];
+
+void entropy_init(void) {
+  // collect entropy from UUID
+  uint32_t w = LL_GetUID_Word0();
+  memcpy(g_hw_entropy, &w, 4);
+  w = LL_GetUID_Word1();
+  memcpy(g_hw_entropy + 4, &w, 4);
+  w = LL_GetUID_Word2();
+  memcpy(g_hw_entropy + 8, &w, 4);
+
+  // set entropy in the OTP randomness block
+  if (secfalse == flash_otp_is_locked(FLASH_OTP_BLOCK_RANDOMNESS)) {
+    uint8_t entropy[FLASH_OTP_BLOCK_SIZE];
+    random_buffer(entropy, FLASH_OTP_BLOCK_SIZE);
+    ensure(flash_otp_write(FLASH_OTP_BLOCK_RANDOMNESS, 0, entropy,
+                           FLASH_OTP_BLOCK_SIZE),
+           NULL);
+    // ensure(flash_otp_lock(FLASH_OTP_BLOCK_RANDOMNESS), NULL);
+  }
+  // collect entropy from OTP randomness block
+  ensure(flash_otp_read(FLASH_OTP_BLOCK_RANDOMNESS, 0, g_hw_entropy + 12,
+                        FLASH_OTP_BLOCK_SIZE),
+         NULL);
+}
+
+void entropy_get(uint8_t *buf) { memcpy(buf, g_hw_entropy, HW_ENTROPY_LEN); }

core/embed/trezorhal/unix/common.c

@@ -74,7 +74,3 @@ void emulator_poll_events(void) {
   SDL_PumpEvents();
   SDL_FilterEvents(emulator_event_filter, NULL);
 }
-
-uint8_t HW_ENTROPY_DATA[HW_ENTROPY_LEN];
-
-void collect_hw_entropy(void) { memzero(HW_ENTROPY_DATA, HW_ENTROPY_LEN); }

core/embed/trezorhal/unix/entropy.c

@@ -0,0 +1,28 @@
+/*
+ * This file is part of the Trezor project, https://trezor.io/
+ *
+ * Copyright (c) SatoshiLabs
+ *
+ * This program 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <string.h>
+
+#include "entropy.h"
+
+static uint8_t g_hw_entropy[HW_ENTROPY_LEN];
+
+void entropy_init(void) { memset(g_hw_entropy, 0, HW_ENTROPY_LEN); }
+
+void entropy_get(uint8_t *buf) { memcpy(buf, g_hw_entropy, HW_ENTROPY_LEN); }

core/embed/unix/main_main.c

@@ -6,11 +6,12 @@
 #endif
 
 #include "common.h"
+#include "entropy.h"
 
 MP_NOINLINE int main_(int argc, char **argv);
 
 int main(int argc, char **argv) {
-  collect_hw_entropy();
+  entropy_init();
 
 #ifdef USE_SECP256K1_ZKP
   ensure(sectrue * (zkp_context_init() == 0), NULL);

core/site_scons/models/stm32f4_common.py

@@ -43,6 +43,7 @@ def stm32f4_common_files(env, defines, sources, paths):
         "embed/trezorhal/stm32f4/board_capabilities.c",
         "embed/trezorhal/stm32f4/boot_args.c",
         "embed/trezorhal/stm32f4/common.c",
+        "embed/trezorhal/stm32f4/entropy.c",
         "embed/trezorhal/stm32f4/fault_handlers.c",
         "embed/trezorhal/stm32f4/flash.c",
         "embed/trezorhal/stm32f4/flash_otp.c",

core/site_scons/models/stm32u5_common.py

@@ -52,6 +52,7 @@ def stm32u5_common_files(env, defines, sources, paths):
         "embed/trezorhal/stm32u5/board_capabilities.c",
         "embed/trezorhal/stm32u5/boot_args.c",
         "embed/trezorhal/stm32u5/common.c",
+        "embed/trezorhal/stm32u5/entropy.c",
         "embed/trezorhal/stm32u5/fault_handlers.c",
         "embed/trezorhal/stm32u5/flash.c",
         "embed/trezorhal/stm32u5/flash_otp.c",