add: base for C99 zygiskd

This commit adds the first base for C99 zygiskd, that is not fully working or code-ready.

zygiskd-new/root_impl/common.c

@@ -0,0 +1,54 @@
+#include <sys/types.h>
+
+#include "kernelsu.h"
+
+#include "common.h"
+
+static enum RootImpl ROOT_IMPL = None;
+
+void root_impls_setup(void) {
+  enum RootImplState ksu_version = ksu_get_kernel_su();
+
+  enum RootImpl impl = None;
+
+  if (ksu_version == Supported) impl = KernelSU;
+
+  ROOT_IMPL = impl;
+}
+
+enum RootImpl get_impl(void) {
+  return ROOT_IMPL;
+}
+
+bool uid_granted_root(uid_t uid) {
+  switch (get_impl()) {
+    case KernelSU: {
+      return ksu_uid_granted_root(uid);
+    }
+    default: {
+      return false;
+    }
+  }
+}
+
+bool uid_should_umount(uid_t uid) {
+  switch (get_impl()) {
+    case KernelSU: {
+      return ksu_uid_should_umount(uid);
+    }
+    default: {
+      return false;
+    }
+  }
+}
+
+bool uid_is_manager(uid_t uid) {
+  switch (get_impl()) {
+    case KernelSU: {
+      return ksu_uid_is_manager(uid);
+    }
+    default: {
+      return false;
+    }
+  }
+}

zygiskd-new/root_impl/common.h

@@ -0,0 +1,22 @@
+#ifndef COMMON_H
+#define COMMON_H
+
+#include "../constants.h"
+
+enum RootImpl {
+  None,
+  Multiple, /* INFO: I know. */
+  KernelSU
+};
+
+void root_impls_setup(void);
+
+enum RootImpl get_impl(void);
+
+bool uid_granted_root(uid_t uid);
+
+bool uid_should_umount(uid_t uid);
+
+bool uid_is_manager(uid_t uid);
+
+#endif /* COMMON_H */

zygiskd-new/root_impl/kernelsu.c

@@ -0,0 +1,68 @@
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/prctl.h>
+#include <errno.h>
+
+#include "../constants.h"
+#include "../utils.h"
+
+#include "kernelsu.h"
+
+#define KERNEL_SU_OPTION 0xdeadbeef
+
+#define CMD_GET_VERSION 2
+#define CMD_UID_GRANTED_ROOT 12
+#define CMD_UID_SHOULD_UMOUNT 13
+
+enum RootImplState ksu_get_kernel_su(void) {
+  int version = 0;
+  prctl(KERNEL_SU_OPTION, CMD_GET_VERSION, &version, 0, 0);
+
+  errno = 0;
+
+  if (version == 0) return Abnormal;
+
+  if (version >= MIN_KSU_VERSION && version <= MAX_KSU_VERSION) return Supported;
+  
+  if (version >= 1 && version <= MIN_KSU_VERSION - 1) return TooOld;
+
+  return Abnormal;
+}
+
+bool ksu_uid_granted_root(uid_t uid) {
+  uint32_t result = 0;
+  bool granted = false;
+  prctl(KERNEL_SU_OPTION, CMD_UID_GRANTED_ROOT, uid, &granted, &result);
+
+  LOGI("ksu_uid_granted_root: %d", granted);
+
+  if (result != KERNEL_SU_OPTION) return false;
+
+  return granted;
+}
+
+bool ksu_uid_should_umount(uid_t uid) {
+  uint32_t result = 0;
+  bool umount = false;
+  prctl(KERNEL_SU_OPTION, CMD_UID_SHOULD_UMOUNT, uid, &umount, &result);
+
+  LOGI("ksu_uid_should_umount: %d", umount);
+
+  if (result != KERNEL_SU_OPTION) return false;
+
+  return umount;
+}
+
+bool ksu_uid_is_manager(uid_t uid) {
+
+  struct stat s;
+  if (stat("/data/user_de/0/me.weishu.kernelsu", &s) == 0) {
+    LOGI("ksu_uid_is_manager: %d", uid);
+
+    return s.st_uid == uid;
+  }
+
+  LOGI("ksu_uid_is_manager: false");
+
+  return false;
+}

zygiskd-new/root_impl/kernelsu.h

@@ -0,0 +1,14 @@
+#ifndef KERNELSU_H
+#define KERNELSU_H
+
+#include "../constants.h"
+
+enum RootImplState ksu_get_kernel_su(void);
+
+bool ksu_uid_granted_root(uid_t uid);
+
+bool ksu_uid_should_umount(uid_t uid);
+
+bool ksu_uid_is_manager(uid_t uid);
+
+#endif