dec++-ify jni part

- Refactoring to c

Co-authored-by: lamadaemon <i@lama.icu>
Co-authored-by: ShirkNeko <109797057+ShirkNeko@users.noreply.github.com>
Signed-off-by: ShirkNeko <109797057+ShirkNeko@users.noreply.github.com>

manager/app/src/main/cpp/ksu.c

@@ -0,0 +1,126 @@
+//
+// Created by weishu on 2022/12/9.
+//
+
+#include <sys/prctl.h>
+#include <stdint.h>
+#include <string.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#include "prelude.h"
+#include "ksu.h"
+
+#define KERNEL_SU_OPTION 0xDEADBEEF
+
+#define CMD_GRANT_ROOT 0
+
+#define CMD_BECOME_MANAGER 1
+#define CMD_GET_VERSION 2
+#define CMD_ALLOW_SU 3
+#define CMD_DENY_SU 4
+#define CMD_GET_SU_LIST 5
+#define CMD_GET_DENY_LIST 6
+#define CMD_CHECK_SAFEMODE 9
+
+#define CMD_GET_APP_PROFILE 10
+#define CMD_SET_APP_PROFILE 11
+
+#define CMD_IS_UID_GRANTED_ROOT 12
+#define CMD_IS_UID_SHOULD_UMOUNT 13
+#define CMD_IS_SU_ENABLED 14
+#define CMD_ENABLE_SU 15
+#define CMD_ENABLE_KPM 100
+#define CMD_HOOK_TYPE 101
+
+static bool ksuctl(int cmd, void* arg1, void* arg2) {
+    int32_t result = 0;
+    int32_t rtn = prctl(KERNEL_SU_OPTION, cmd, arg1, arg2, &result);
+
+    return result == KERNEL_SU_OPTION && rtn == -1;
+}
+
+bool become_manager(const char* pkg) {
+    char param[128];
+    uid_t uid = getuid();
+    uint32_t userId = uid / 100000;
+    if (userId == 0) {
+        sprintf(param, "/data/data/%s", pkg);
+    } else {
+        snprintf(param, sizeof(param), "/data/user/%d/%s", userId, pkg);
+    }
+
+    return ksuctl(CMD_BECOME_MANAGER, param, NULL);
+}
+
+// cache the result to avoid unnecessary syscall
+static bool is_lkm;
+int get_version() {
+    int32_t version = -1;
+    int32_t lkm = 0;
+    ksuctl(CMD_GET_VERSION, &version, &lkm);
+    if (!is_lkm && lkm != 0) {
+        is_lkm = true;
+    }
+    return version;
+}
+
+bool get_allow_list(int *uids, int *size) {
+    return ksuctl(CMD_GET_SU_LIST, uids, size);
+}
+
+bool is_safe_mode() {
+    return ksuctl(CMD_CHECK_SAFEMODE, NULL, NULL);
+}
+
+bool is_lkm_mode() {
+    // you should call get_version first!
+    return is_lkm;
+}
+
+bool uid_should_umount(int uid) {
+    int should;
+    return ksuctl(CMD_IS_UID_SHOULD_UMOUNT, (void*) ((size_t) uid), &should) && should;
+}
+
+bool set_app_profile(const struct app_profile* profile) {
+    return ksuctl(CMD_SET_APP_PROFILE, (void*) profile, NULL);
+}
+
+bool get_app_profile(char* key, struct app_profile* profile) {
+    return ksuctl(CMD_GET_APP_PROFILE, profile, NULL);
+}
+
+bool set_su_enabled(bool enabled) {
+    return ksuctl(CMD_ENABLE_SU, (void*) enabled, NULL);
+}
+
+bool is_su_enabled() {
+    int enabled = true;
+    // if ksuctl failed, we assume su is enabled, and it cannot be disabled.
+    ksuctl(CMD_IS_SU_ENABLED, &enabled, NULL);
+    return enabled;
+}
+
+bool is_KPM_enable() {
+    int enabled = false;
+    ksuctl(CMD_ENABLE_KPM, &enabled, NULL);
+    return enabled;
+}
+
+bool get_hook_type(char* hook_type, size_t size) {
+    if (hook_type == NULL || size == 0) {
+        return false;
+    }
+
+    static char cached_hook_type[16] = {0};
+    if (cached_hook_type[0] == '\0') {
+        if (!ksuctl(CMD_HOOK_TYPE, cached_hook_type, NULL)) {
+            strcpy(cached_hook_type, "Unknown");
+        }
+    }
+
+    strncpy(hook_type, cached_hook_type, size);
+    hook_type[size - 1] = '\0';
+    return true;
+}