本文介紹編譯Android13 ROOT權限固件的方法，觸覺智能RK3562開發板演示，通用各類瑞芯微RK3566 RK3568 RK3588等

本文介紹編譯Android13 ROOT權限固件的方法，觸覺智能RK3562開發板演示，搭載4核A53處理器，主頻高達2.0GHz；內置獨立1Tops算力NPU，可應用于物聯網網關、平板電腦、智能家居、教育電子、工業顯示與控制等行業。
關閉selinux
修改此文件（"+"號為修改內容）

device/rockchip/common/BoardConfig.mk
BOARD_BOOT_HEADER_VERSION ?= 2
BOARD_MKBOOTIMG_ARGS :=
BOARD_PREBUILT_DTBOIMAGE ?= $(TARGET_DEVICE_DIR)/dtbo.img
BOARD_ROCKCHIP_VIRTUAL_AB_ENABLE ?= false
-BOARD_SELINUX_ENFORCING ?= true
+BOARD_SELINUX_ENFORCING ?= false

注釋用戶組權限檢測
修改此文件（"+"號為修改內容）

system/extras/su/su.cpp

void extract_uidgids(const char* uidgids, uid_t* uid, gid_t*
gid, gid_t* gids, i
}
int main(int argc, char** argv) {

• uid_t current_uid = getuid();
• if (current_uid != AID_ROOT && current_uid != AID_SHELL) error(1, 0, "notallowed");

• //uid_t current_uid = getuid();
• //if (current_uid != AID_ROOT && current_uid != AID_SHELL) error(1, 0, "notallowed");
  給su文件默認授予root權限
  修改此文件（"+"號為修改內容）
  system/core/libcutils/fs_config.cpp

static const struct fs_path_config android_dirs[] = {
{ 00751, AID_ROOT, AID_SHELL, 0, "system/bin" },
{ 00755, AID_ROOT, AID_ROOT, 0, "system/etc/ppp" },
{ 00755, AID_ROOT, AID_SHELL, 0, "system/vendor" },

• { 00750, AID_ROOT, AID_SHELL, 0, "system/xbin" },

• { 00755, AID_ROOT, AID_SHELL, 0, "system/xbin" },
  { 00751, AID_ROOT, AID_SHELL, 0, "system/apex//bin" },
  { 00751, AID_ROOT, AID_SHELL, 0, "system_ext/bin" },
  { 00751, AID_ROOT, AID_SHELL, 0, "system_ext/apex//bin" },
  static const struct fs_path_config android_files[] = {
  // the following two files are INTENTIONALLY set-uid, but they
  // are NOT included on user builds.
  { 06755, AID_ROOT, AID_ROOT, 0, "system/xbin/procmem" },

• { 04750, AID_ROOT, AID_SHELL, 0, "system/xbin/su" },

• { 06755, AID_ROOT, AID_SHELL, 0, "system/xbin/su" },
  然后修改此文件（"+"號為修改內容）
  frameworks/base/core/jni/com_android_internal_os_Zygote.cpp
  static void DropCapabilitiesBoundingSet(fail_fn_t fail_fn) {
  +/*
  for (int i = 0; prctl(PR_CAPBSET_READ, i, 0, 0, 0) >= 0; i++) {;
  if (prctl(PR_CAPBSET_DROP, i, 0, 0, 0) == -1) {
  if (errno == EINVAL) {
  ALOGE("prctl(PR_CAPBSET_DROP) failed with EINVAL. Please verify "
  "your kernel is compiled with file capabilities support");
  } else {
  fail_fn(CREATE_ERROR("prctl(PR_CAPBSET_DROP, %d) failed: %s", i, strerror(errno)));
  }
  }
  }
• */
  }
  最后修改此文件（"+"號為修改內容）
  kernel-5.10/security/commoncap.c
  int cap_task_setnice(struct task_struct *p, int nice)
  static int cap_prctl_drop(unsigned long cap)
  {
  struct cred new;
  +/
  if (!ns_capable(current_user_ns(), CAP_SETPCAP))
  return -EPERM;
  if (!cap_valid(cap))
  return -EINVAL;

+*/
new = prepare_creds();

源碼編譯并驗證固件是否ROOT
修改完上面三個步驟的文件后，重新編譯內核和安卓源碼，執行以下命令：

make -j4

下載RootChecker測試APK軟件包（自行下載）,可通過ADB命令或者U盤安裝,安裝后按照提示點擊按鈕檢查root。

root成功如圖：