From 997c27adb3ab7d99a48cad03efa5ff0564ddbf70 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ond=C5=99ej=20Vejpustek?= <ondrej.vejpustek@satoshilabs.com>
Date: Tue, 19 Nov 2024 13:34:08 +0100
Subject: [PATCH] refactor(core): use separate implementation of secret.c for
 unix

[no changelog]
---
 core/embed/sec/secret/unix/secret.c | 138 +++++++++++++++++++++++++++-
 1 file changed, 137 insertions(+), 1 deletion(-)
 mode change 120000 => 100644 core/embed/sec/secret/unix/secret.c

diff --git a/core/embed/sec/secret/unix/secret.c b/core/embed/sec/secret/unix/secret.c
deleted file mode 120000
index 91e08f2ec9..0000000000
--- a/core/embed/sec/secret/unix/secret.c
+++ /dev/null
@@ -1 +0,0 @@
-../stm32f4/secret.c
\ No newline at end of file
diff --git a/core/embed/sec/secret/unix/secret.c b/core/embed/sec/secret/unix/secret.c
new file mode 100644
index 0000000000..970f951acc
--- /dev/null
+++ b/core/embed/sec/secret/unix/secret.c
@@ -0,0 +1,137 @@
+#include <trezor_model.h>
+#include <trezor_rtl.h>
+
+#include <sec/secret.h>
+#include <sys/mpu.h>
+#include <util/flash.h>
+
+#ifdef KERNEL_MODE
+
+static secbool bootloader_locked_set = secfalse;
+static secbool bootloader_locked = secfalse;
+
+secbool secret_verify_header(void) {
+  uint8_t* addr = (uint8_t*)flash_area_get_address(&SECRET_AREA, 0,
+                                                   sizeof(SECRET_HEADER_MAGIC));
+
+  if (addr == NULL) {
+    return secfalse;
+  }
+
+  mpu_mode_t mpu_mode = mpu_reconfig(MPU_MODE_SECRET);
+
+  bootloader_locked =
+      memcmp(addr, SECRET_HEADER_MAGIC, sizeof(SECRET_HEADER_MAGIC)) == 0
+          ? sectrue
+          : secfalse;
+
+  mpu_restore(mpu_mode);
+
+  bootloader_locked_set = sectrue;
+  return bootloader_locked;
+}
+
+secbool secret_bootloader_locked(void) {
+  if (bootloader_locked_set != sectrue) {
+    // Set bootloader_locked.
+    secret_verify_header();
+  }
+
+  return bootloader_locked;
+}
+
+void secret_write_header(void) {
+  uint8_t header[SECRET_HEADER_LEN] = {0};
+  memcpy(header, SECRET_HEADER_MAGIC, 4);
+  secret_write(header, 0, SECRET_HEADER_LEN);
+}
+
+void secret_write(const uint8_t* data, uint32_t offset, uint32_t len) {
+  mpu_mode_t mpu_mode = mpu_reconfig(MPU_MODE_SECRET);
+  ensure(flash_unlock_write(), "secret write");
+  for (int i = 0; i < len; i++) {
+    ensure(flash_area_write_byte(&SECRET_AREA, offset + i, data[i]),
+           "secret write");
+  }
+  ensure(flash_lock_write(), "secret write");
+  mpu_restore(mpu_mode);
+}
+
+secbool secret_read(uint8_t* data, uint32_t offset, uint32_t len) {
+  if (sectrue != secret_verify_header()) {
+    return secfalse;
+  }
+
+  uint8_t* addr = (uint8_t*)flash_area_get_address(&SECRET_AREA, offset, len);
+
+  if (addr == NULL) {
+    return secfalse;
+  }
+
+  mpu_mode_t mpu_mode = mpu_reconfig(MPU_MODE_SECRET);
+  memcpy(data, addr, len);
+  mpu_restore(mpu_mode);
+
+  return sectrue;
+}
+
+secbool secret_wiped(void) {
+  uint32_t size = flash_area_get_size(&SECRET_AREA);
+  secbool wiped = sectrue;
+
+  mpu_mode_t mpu_mode = mpu_reconfig(MPU_MODE_SECRET);
+
+  for (int i = 0; i < size; i += 4) {
+    uint32_t* addr = (uint32_t*)flash_area_get_address(&SECRET_AREA, i, 4);
+    if (addr == NULL) {
+      wiped = secfalse;
+      break;
+    }
+    if (*addr != 0xFFFFFFFF) {
+      wiped = secfalse;
+      break;
+    }
+  }
+
+  mpu_restore(mpu_mode);
+
+  return wiped;
+}
+
+void secret_erase(void) {
+  mpu_mode_t mpu_mode = mpu_reconfig(MPU_MODE_SECRET);
+  ensure(flash_area_erase(&SECRET_AREA, NULL), "secret erase");
+  mpu_restore(mpu_mode);
+}
+
+secbool secret_optiga_set(const uint8_t secret[SECRET_OPTIGA_KEY_LEN]) {
+  secret_erase();
+  secret_write_header();
+  secret_write(secret, SECRET_OPTIGA_KEY_OFFSET, SECRET_OPTIGA_KEY_LEN);
+  return sectrue;
+}
+
+secbool secret_optiga_get(uint8_t dest[SECRET_OPTIGA_KEY_LEN]) {
+  return secret_read(dest, SECRET_OPTIGA_KEY_OFFSET, SECRET_OPTIGA_KEY_LEN);
+}
+
+secbool secret_optiga_present(void) {
+  return (sectrue != secret_wiped()) * sectrue;
+}
+
+secbool secret_optiga_writable(void) { return secret_wiped(); }
+
+void secret_optiga_erase(void) { secret_erase(); }
+
+void secret_prepare_fw(secbool allow_run_with_secret, secbool _trust_all) {
+#ifdef USE_OPTIGA
+  if (sectrue != allow_run_with_secret && sectrue != secret_wiped()) {
+    // This function does not return
+    show_install_restricted_screen();
+  }
+#endif
+}
+
+void secret_init(void) {}
+
+#endif  // KERNEL_MODE