Bump to 0.5.1

README.md

@@ -2,25 +2,15 @@
 
 Zygisk loader for KernelSU, allowing Zygisk modules to run without Magisk environment.
 
-Also works as standalone loader for Magisk on purpose of getting rid of LD_PRELOAD. (Coming soon)
+Also works as standalone loader for Magisk on purpose of getting rid of LD_PRELOAD.
 
 ## Requirements
 
-+ Minimal KernelSU version: 10575
-+ Minimal ksud version: 10616
++ Minimal KernelSU version: 10654
++ Minimal ksud version: 10647
 + Full SELinux patch support (If non-gki kernel)
++ No multiple root implementation installed
 
 ## Compatibility
 
 Should work with everything except those rely on Magisk internal behaviors.
-
-## Development road map
-
-- [x] [Inject] Basic Zygisk loader
-- [x] [Inject] Stabilize injector
-- [x] [Inject] Unload
-- [x] [Daemon] Linker namespace
-- [x] [Daemon] Separate zygiskd process
-- [x] [Daemon] Handle 64 bit only devices
-- [x] [Daemon] Handle zygote death
-- [ ] [ Misc ] Support Magisk out of box

build.gradle.kts

@@ -31,8 +31,12 @@ val gitCommitHash = "git rev-parse --verify --short HEAD".execute()
 
 val moduleId by extra("zygisksu")
 val moduleName by extra("Zygisk on KernelSU")
-val verName by extra("v4-0.4.0")
+val verName by extra("v4-0.5.1")
 val verCode by extra(gitCommitCount)
+val minKsuVersion by extra(10654)
+val minKsudVersion by extra(10647)
+val maxKsuVersion by extra(20000)
+val minMagiskVersion by extra(25000)
 
 val androidMinSdkVersion by extra(29)
 val androidTargetSdkVersion by extra(33)

loader/src/common/daemon.cpp

@@ -58,6 +58,17 @@ namespace zygiskd {
         return socket_utils::read_string(fd);
     }
 
+    uint32_t GetProcessFlags(uid_t uid) {
+        UniqueFd fd = Connect(1);
+        if (fd == -1) {
+            PLOGE("GetProcessFlags");
+            return 0;
+        }
+        socket_utils::write_u8(fd, (uint8_t) SocketAction::GetProcessFlags);
+        socket_utils::write_u32(fd, uid);
+        return socket_utils::read_u32(fd);
+    }
+
     std::vector<Module> ReadModules() {
         std::vector<Module> modules;
         UniqueFd fd = Connect(1);

loader/src/common/socket_utils.cpp

@@ -90,6 +90,10 @@ namespace socket_utils {
         return read_exact_or<uint8_t>(fd, 0);
     }
 
+    uint32_t read_u32(int fd) {
+        return read_exact_or<uint32_t>(fd, 0);
+    }
+
     size_t read_usize(int fd) {
         return read_exact_or<size_t>(fd, 0);
     }
@@ -110,6 +114,10 @@ namespace socket_utils {
         return write_exact<uint8_t>(fd, val);
     }
 
+    bool write_u32(int fd, uint32_t val) {
+        return write_exact<uint32_t>(fd, val);
+    }
+
     bool write_string(int fd, std::string_view str) {
         return write_usize(fd, str.size()) && str.size() == xwrite(fd, str.data(), str.size());
     }

loader/src/include/daemon.h

@@ -54,6 +54,7 @@ namespace zygiskd {
         PingHeartBeat,
         RequestLogcatFd,
         ReadNativeBridge,
+        GetProcessFlags,
         ReadModules,
         RequestCompanionSocket,
         GetModuleDir,
@@ -67,6 +68,8 @@ namespace zygiskd {
 
     std::vector<Module> ReadModules();
 
+    uint32_t GetProcessFlags(uid_t uid);
+
     int ConnectCompanion(size_t index);
 
     int GetModuleDir(size_t index);

loader/src/include/socket_utils.h

@@ -13,12 +13,16 @@ namespace socket_utils {
 
     uint8_t read_u8(int fd);
 
+    uint32_t read_u32(int fd);
+
     size_t read_usize(int fd);
 
     std::string read_string(int fd);
 
     bool write_u8(int fd, uint8_t val);
 
+    bool write_u32(int fd, uint32_t val);
+
     int recv_fd(int fd);
 
     bool write_usize(int fd, size_t val);

loader/src/injector/entry.cpp

@@ -26,10 +26,3 @@ void entry(void *handle) {
     LOGD("Load injector successfully");
     hook_functions();
 }
-
-// The following code runs in zygote/app process
-
-static inline bool should_load_modules(uint32_t flags) {
-    return (flags & UNMOUNT_MASK) != UNMOUNT_MASK &&
-           (flags & PROCESS_IS_MAGISK_APP) != PROCESS_IS_MAGISK_APP;
-}

loader/src/injector/hide.cpp

@@ -1,22 +0,0 @@
-#include <sys/mount.h>
-
-#include "logging.h"
-#include "misc.hpp"
-#include "zygisk.hpp"
-
-using namespace std::string_view_literals;
-
-static void lazy_unmount(const char* mountpoint) {
-    if (umount2(mountpoint, MNT_DETACH) != -1)
-        LOGD("Unmounted (%s)", mountpoint);
-}
-
-void revert_unmount() {
-    parse_mnt("/proc/self/mounts", [](mntent* mentry) {
-        if (mentry->mnt_fsname == "/data/adb/ksu/modules"sv ||
-            std::string_view(mentry->mnt_opts).find("/data/adb/ksu/modules") != std::string_view::npos) {
-            lazy_unmount(mentry->mnt_fsname);
-        }
-        return true;
-    });
-}

loader/src/injector/hook.cpp

@@ -566,15 +566,13 @@ void HookContext::run_modules_post() {
 /* Zygisksu changed: Load module fds */
 void HookContext::app_specialize_pre() {
     flags[APP_SPECIALIZE] = true;
+    info_flags = zygiskd::GetProcessFlags(g_ctx->args.app->uid);
     run_modules_pre();
 }
 
 
 void HookContext::app_specialize_post() {
     run_modules_post();
-    if (info_flags & PROCESS_IS_MAGISK_APP) {
-        setenv("ZYGISK_ENABLED", "1", 1);
-    }
 
     // Cleanups
     env->ReleaseStringUTFChars(args.app->nice_name, process);

loader/src/injector/misc.cpp

@@ -35,6 +35,31 @@ void parse_mnt(const char* file, const std::function<bool(mntent*)>& fn) {
     }
 }
 
+std::list<std::string> split_str(std::string_view s, std::string_view delimiter) {
+    std::list<std::string> ret;
+    size_t pos = 0;
+    while (pos < s.size()) {
+        auto next = s.find(delimiter, pos);
+        if (next == std::string_view::npos) {
+            ret.emplace_back(s.substr(pos));
+            break;
+        }
+        ret.emplace_back(s.substr(pos, next - pos));
+        pos = next + delimiter.size();
+    }
+    return ret;
+}
+
+std::string join_str(const std::list<std::string>& list, std::string_view delimiter) {
+    std::string ret;
+    for (auto& s : list) {
+        if (!ret.empty())
+            ret += delimiter;
+        ret += s;
+    }
+    return ret;
+}
+
 sDIR make_dir(DIR *dp) {
     return sDIR(dp, [](DIR *dp){ return dp ? closedir(dp) : 1; });
 }

loader/src/injector/misc.hpp

@@ -2,10 +2,12 @@
 
 #include <dirent.h>
 #include <functional>
+#include <list>
 #include <memory>
 #include <mntent.h>
 #include <pthread.h>
 #include <stdio.h>
+#include <string>
 #include <string_view>
 
 #include "logging.h"
@@ -34,6 +36,16 @@ private:
 using thread_entry = void *(*)(void *);
 int new_daemon_thread(thread_entry entry, void *arg);
 
+static inline bool str_contains(std::string_view s, std::string_view ss) {
+    return s.find(ss) != std::string_view::npos;
+}
+static inline bool str_starts(std::string_view s, std::string_view ss) {
+    return s.size() >= ss.size() && s.compare(0, ss.size(), ss) == 0;
+}
+static inline bool str_ends(std::string_view s, std::string_view ss) {
+    return s.size() >= ss.size() && s.compare(s.size() - ss.size(), std::string_view::npos, ss) == 0;
+}
+
 template<typename T, typename Impl>
 class stateless_allocator {
 public:
@@ -78,6 +90,25 @@ static inline sFILE xopen_file(int fd, const char *mode) {
     return make_file(fdopen(fd, mode));
 }
 
+template <typename T>
+class reversed_container {
+public:
+    reversed_container(T &base) : base(base) {}
+    decltype(std::declval<T>().rbegin()) begin() { return base.rbegin(); }
+    decltype(std::declval<T>().crbegin()) begin() const { return base.crbegin(); }
+    decltype(std::declval<T>().crbegin()) cbegin() const { return base.crbegin(); }
+    decltype(std::declval<T>().rend()) end() { return base.rend(); }
+    decltype(std::declval<T>().crend()) end() const { return base.crend(); }
+    decltype(std::declval<T>().crend()) cend() const { return base.crend(); }
+private:
+    T &base;
+};
+
+template <typename T>
+reversed_container<T> reversed(T &base) {
+    return reversed_container<T>(base);
+}
+
 template<class T>
 static inline void default_new(T *&p) { p = new T(); }
 
@@ -97,6 +128,10 @@ int parse_int(std::string_view s);
 
 void parse_mnt(const char* file, const std::function<bool(mntent*)>& fn);
 
+std::list<std::string> split_str(std::string_view s, std::string_view delimiter);
+
+std::string join_str(const std::list<std::string>& list, std::string_view delimiter);
+
 template <typename T>
 static inline T align_to(T v, int a) {
     static_assert(std::is_integral<T>::value);

loader/src/injector/module.hpp

@@ -111,12 +111,9 @@ namespace {
         PROCESS_GRANTED_ROOT = zygisk::StateFlag::PROCESS_GRANTED_ROOT,
         PROCESS_ON_DENYLIST = zygisk::StateFlag::PROCESS_ON_DENYLIST,
 
-        PROCESS_IS_SYS_UI = (1u << 29),
-        DENYLIST_ENFORCING = (1u << 30),
-        PROCESS_IS_MAGISK_APP = (1u << 31),
+        PROCESS_IS_SYS_UI = (1u << 31),
 
-        UNMOUNT_MASK = (PROCESS_ON_DENYLIST | DENYLIST_ENFORCING),
-        PRIVATE_MASK = (PROCESS_IS_SYS_UI | DENYLIST_ENFORCING | PROCESS_IS_MAGISK_APP)
+        PRIVATE_MASK = PROCESS_IS_SYS_UI
     };
 
     struct api_abi_base {

loader/src/injector/unmount.cpp

@@ -0,0 +1,71 @@
+#include <sys/mount.h>
+
+#include "logging.h"
+#include "misc.hpp"
+#include "zygisk.hpp"
+
+using namespace std::string_view_literals;
+
+static void lazy_unmount(const char* mountpoint) {
+    if (umount2(mountpoint, MNT_DETACH) != -1) {
+        LOGD("Unmounted (%s)", mountpoint);
+    } else {
+        LOGW("Failed to unmount: %s (%s)", strerror(errno), mountpoint);
+    }
+}
+
+#define PARSE_OPT(name, flag)   \
+    if (opt == name) {          \
+        flags |= (flag);        \
+        return true;            \
+    }
+
+void revert_unmount() {
+    std::vector<std::string> targets;
+    std::list<std::pair<std::string, std::string>> backups;
+
+    targets.emplace_back("/data/adb/ksu/modules");
+    parse_mnt("/proc/self/mounts", [&](mntent* mentry) {
+        if (str_starts(mentry->mnt_fsname, "/data/adb/")) {
+            targets.emplace_back(mentry->mnt_dir);
+        }
+        if (mentry->mnt_type == "overlay"sv) {
+            if (str_contains(mentry->mnt_opts, "/data/adb/ksu/modules")) {
+                targets.emplace_back(mentry->mnt_dir);
+            } else {
+                backups.emplace_back(mentry->mnt_dir, mentry->mnt_opts);
+            }
+        }
+        return true;
+    });
+
+    for (auto& s: reversed(targets)) {
+        lazy_unmount(s.data());
+    }
+
+    parse_mnt("/proc/self/mounts", [&](mntent* mentry) {
+        if (mentry->mnt_type == "overlay"sv) {
+            backups.remove_if([&](auto& mnt) {
+                return mnt.first == mentry->mnt_dir && mnt.second == mentry->mnt_opts;
+            });
+        }
+        return true;
+    });
+
+    for (auto& mnt: backups) {
+        auto opts = split_str(mnt.second, ",");
+        unsigned long flags = 0;
+        opts.remove_if([&](auto& opt) {
+            PARSE_OPT(MNTOPT_RO, MS_RDONLY)
+            PARSE_OPT(MNTOPT_NOSUID, MS_NOSUID)
+            PARSE_OPT("relatime", MS_RELATIME)
+            return false;
+        });
+        auto mnt_data = join_str(opts, ",");
+        if (mount("overlay", mnt.first.data(), "overlay", flags, mnt_data.data()) != -1) {
+            LOGD("Remounted (%s)", mnt.first.data());
+        } else {
+            LOGW("Failed to remount: %s (%s, %s)", strerror(errno), mnt.first.data(), mnt_data.data());
+        }
+    }
+}

module/build.gradle.kts

@@ -11,6 +11,10 @@ val moduleId: String by rootProject.extra
 val moduleName: String by rootProject.extra
 val verCode: Int by rootProject.extra
 val verName: String by rootProject.extra
+val minKsuVersion: Int by rootProject.extra
+val minKsudVersion: Int by rootProject.extra
+val maxKsuVersion: Int by rootProject.extra
+val minMagiskVersion: Int by rootProject.extra
 
 android.buildFeatures {
     androidResources = false
@@ -49,7 +53,11 @@ androidComponents.onVariants { variant ->
         from("$projectDir/src") {
             include("customize.sh", "daemon.sh")
             val tokens = mapOf(
-                "DEBUG" to if (buildTypeLowered == "debug") "true" else "false"
+                "DEBUG" to if (buildTypeLowered == "debug") "true" else "false",
+                "MIN_KSU_VERSION" to "$minKsuVersion",
+                "MIN_KSUD_VERSION" to "$minKsudVersion",
+                "MAX_KSU_VERSION" to "$maxKsuVersion",
+                "MIN_MAGISK_VERSION" to "$minMagiskVersion",
             )
             filter<ReplaceTokens>("tokens" to tokens)
             filter<FixCrLfFilter>("eol" to FixCrLfFilter.CrLf.newInstance("lf"))
@@ -106,7 +114,7 @@ androidComponents.onVariants { variant ->
     val installMagiskTask = task<Exec>("installMagisk$variantCapped") {
         group = "module"
         dependsOn(pushTask)
-        commandLine("adb", "shell", "su", "-c", "KSU=true magisk --install-module /data/local/tmp/$zipFileName")
+        commandLine("adb", "shell", "su", "-c", "magisk --install-module /data/local/tmp/$zipFileName")
     }
 
     task<Exec>("installKsuAndReboot$variantCapped") {

module/src/customize.sh

@@ -2,28 +2,56 @@
 SKIPUNZIP=1
 
 DEBUG=@DEBUG@
+MIN_KSU_VERSION=@MIN_KSU_VERSION@
+MIN_KSUD_VERSION=@MIN_KSUD_VERSION@
+MAX_KSU_VERSION=@MAX_KSU_VERSION@
+MIN_MAGISK_VERSION=@MIN_MAGISK_VERSION@
 
-if [ $BOOTMODE ] && [ "$KSU" == "true" ]; then
+if [ "$BOOTMODE" ] && [ "$KSU" ]; then
   ui_print "- Installing from KernelSU app"
+  ui_print "- KernelSU version: $KSU_KERNEL_VER_CODE (kernel) + $KSU_VER_CODE (ksud)"
+  if ! [ "$KSU_KERNEL_VER_CODE" ] || [ "$KSU_KERNEL_VER_CODE" -lt "$MIN_KSU_VERSION" ]; then
+    ui_print "*********************************************************"
+    ui_print "! KernelSU version is too old!"
+    ui_print "! Please update KernelSU to latest version"
+    abort    "*********************************************************"
+  elif [ "$KSU_KERNEL_VER_CODE" -ge "$MAX_KSU_VERSION" ]; then
+    ui_print "*********************************************************"
+    ui_print "! KernelSU version abnormal!"
+    ui_print "! Please integrate KernelSU into your kernel"
+    ui_print "  as submodule instead of copying the source code"
+    abort    "*********************************************************"
+  fi
+  if ! [ "$KSU_VER_CODE" ] || [ "$KSU_VER_CODE" -lt "$MIN_KSUD_VERSION" ]; then
+    ui_print "*********************************************************"
+    ui_print "! ksud version is too old!"
+    ui_print "! Please update KernelSU Manager to latest version"
+    abort    "*********************************************************"
+  fi
+  if [ "$(which magisk)" ]; then
+    ui_print "*********************************************************"
+    ui_print "! Multiple root implementation is NOT supported!"
+    ui_print "! Please uninstall Magisk before installing Zygisksu"
+    abort    "*********************************************************"
+  fi
+elif [ "$BOOTMODE" ] && [ "$MAGISK_VER_CODE" ]; then
+  ui_print "- Installing from Magisk app"
+  if [ "$MAGISK_VER_CODE" -lt "$MIN_MAGISK_VERSION" ]; then
+    ui_print "*********************************************************"
+    ui_print "! Magisk version is too old!"
+    ui_print "! Please update Magisk to latest version"
+    abort    "*********************************************************"
+  fi
 else
   ui_print "*********************************************************"
-  ui_print "! Install from recovery or Magisk is NOT supported"
-  ui_print "! Please install from KernelSU app"
-  abort "*********************************************************"
+  ui_print "! Install from recovery is not supported"
+  ui_print "! Please install from KernelSU or Magisk app"
+  abort    "*********************************************************"
 fi
 
 VERSION=$(grep_prop version "${TMPDIR}/module.prop")
 ui_print "- Installing Zygisksu $VERSION"
 
-# check KernelSU
-ui_print "- KernelSU version: $KSU_KERNEL_VER_CODE (kernel) + $KSU_VER_CODE (ksud)"
-if [ "$KSU_KERNEL_VER_CODE" -lt 10575 ]; then
-  ui_print "*********************************************************"
-  ui_print "! KernelSU version is too old!"
-  ui_print "! Please update KernelSU to latest version"
-  abort    "*********************************************************"
-fi
-
 # check android
 if [ "$API" -lt 29 ]; then
   ui_print "! Unsupported sdk: $API"
@@ -52,12 +80,14 @@ extract "$ZIPFILE" 'customize.sh'  "$TMPDIR/.vunzip"
 extract "$ZIPFILE" 'verify.sh'     "$TMPDIR/.vunzip"
 extract "$ZIPFILE" 'sepolicy.rule' "$TMPDIR"
 
-ui_print "- Checking SELinux patches"
-if ! check_sepolicy "$TMPDIR/sepolicy.rule"; then
-  ui_print "*********************************************************"
-  ui_print "! Unable to apply SELinux patches!"
-  ui_print "! Your kernel may not support SELinux patch fully"
-  abort    "*********************************************************"
+if [ "$KSU" ]; then
+  ui_print "- Checking SELinux patches"
+  if ! check_sepolicy "$TMPDIR/sepolicy.rule"; then
+    ui_print "*********************************************************"
+    ui_print "! Unable to apply SELinux patches!"
+    ui_print "! Your kernel may not support SELinux patch fully"
+    abort    "*********************************************************"
+  fi
 fi
 
 ui_print "- Extracting module files"
@@ -65,6 +95,7 @@ extract "$ZIPFILE" 'daemon.sh'       "$MODPATH"
 extract "$ZIPFILE" 'module.prop'     "$MODPATH"
 extract "$ZIPFILE" 'post-fs-data.sh' "$MODPATH"
 extract "$ZIPFILE" 'sepolicy.rule'   "$MODPATH"
+extract "$ZIPFILE" 'service.sh'      "$MODPATH"
 
 HAS32BIT=false && [ -d "/system/lib" ] && HAS32BIT=true
 HAS64BIT=false && [ -d "/system/lib64" ] && HAS64BIT=true

module/src/post-fs-data.sh

@@ -1,8 +1,24 @@
 #!/system/bin/sh
 
 MODDIR=${0%/*}
+if [ "$ZYGISK_ENABLED" ]; then
+  exit 0
+fi
 
-cd $MODDIR
+cd "$MODDIR"
 export NATIVE_BRIDGE=$(getprop ro.dalvik.vm.native.bridge)
 
-unshare -m sh -c "./daemon.sh $@&"
+if [ "$(which magisk)" ] && [ ".." -ef "/data/adb/modules" ]; then
+  for file in ../*; do
+    if [ -d "$file" ] && [ -d "$file/zygisk" ] && ! [ -f "$file/disable" ]; then
+      if [ -f "$file/post-fs-data.sh" ]; then
+        cd "$file"
+        log -p i -t "zygisksu" "Manually trigger post-fs-data.sh for $file"
+        sh "$(realpath ./post-fs-data.sh)"
+        cd "$MODDIR"
+      fi
+    fi
+  done
+fi
+
+sh -c "./daemon.sh $@&"

module/src/sepolicy.rule

@@ -10,3 +10,6 @@ allow * magisk_file lnk_file *
 allow * magisk_file sock_file *
 
 allow system_server system_server process execmem
+allow zygote mnt_vendor_file dir search
+allow zygote system_file dir mounton
+allow zygote labeledfs filesystem mount

module/src/service.sh

@@ -0,0 +1,21 @@
+#!/system/bin/sh
+
+MODDIR=${0%/*}
+if [ "$ZYGISK_ENABLED" ]; then
+  exit 0
+fi
+
+cd "$MODDIR"
+
+if [ "$(which magisk)" ] && [ ".." -ef "/data/adb/modules" ]; then
+  for file in ../*; do
+    if [ -d "$file" ] && [ -d "$file/zygisk" ] && ! [ -f "$file/disable" ]; then
+      if [ -f "$file/service.sh" ]; then
+        cd "$file"
+        log -p i -t "zygisksu" "Manually trigger service.sh for $file"
+        sh "$(realpath ./service.sh)"
+        cd "$MODDIR"
+      fi
+    fi
+  done
+fi

zygiskd/Cargo.toml

@@ -10,11 +10,13 @@ android_logger = "0.12.0"
 anyhow = { version = "1.0.68", features = ["backtrace"] }
 clap = { version = "4.1.4", features = ["derive"] }
 const_format = "0.2.5"
+konst = "0.3.4"
 lazy_static = "1.4.0"
 log = "0.4.17"
 memfd = "0.6.2"
 nix = "0.26.2"
 num_enum = "0.5.9"
+once_cell = "1.17.1"
 passfd = "0.1.5"
 rand = "0.8.5"
 

zygiskd/build.gradle.kts

@@ -5,6 +5,9 @@ plugins {
 
 val verName: String by rootProject.extra
 val verCode: Int by rootProject.extra
+val minKsuVersion: Int by rootProject.extra
+val maxKsuVersion: Int by rootProject.extra
+val minMagiskVersion: Int by rootProject.extra
 
 android.buildFeatures {
     androidResources = false
@@ -23,5 +26,8 @@ cargo {
         spec.environment("ANDROID_NDK_HOME", android.ndkDirectory.path)
         spec.environment("VERSION_CODE", verCode)
         spec.environment("VERSION_NAME", verName)
+        spec.environment("MIN_KSU_VERSION", minKsuVersion)
+        spec.environment("MAX_KSU_VERSION", maxKsuVersion)
+        spec.environment("MIN_MAGISK_VERSION", minMagiskVersion)
     }
 }

zygiskd/src/constants.rs

@@ -1,10 +1,15 @@
 use const_format::concatcp;
+use konst::primitive::parse_i32;
+use konst::unwrap_ctx;
 use log::LevelFilter;
 use num_enum::TryFromPrimitive;
 
 pub const VERSION_NAME: &str = env!("VERSION_NAME");
 pub const VERSION_CODE: &str = env!("VERSION_CODE");
 pub const VERSION_FULL: &str = concatcp!(VERSION_NAME, " (", VERSION_CODE, ")");
+pub const MIN_KSU_VERSION: i32 = unwrap_ctx!(parse_i32(env!("MIN_KSU_VERSION")));
+pub const MAX_KSU_VERSION: i32 = unwrap_ctx!(parse_i32(env!("MAX_KSU_VERSION")));
+pub const MIN_MAGISK_VERSION: i32 = unwrap_ctx!(parse_i32(env!("MIN_MAGISK_VERSION")));
 
 #[cfg(debug_assertions)]
 pub const MAX_LOG_LEVEL: LevelFilter = LevelFilter::Trace;
@@ -38,7 +43,13 @@ pub enum DaemonSocketAction {
     PingHeartbeat,
     RequestLogcatFd,
     ReadNativeBridge,
+    GetProcessFlags,
     ReadModules,
     RequestCompanionSocket,
     GetModuleDir,
 }
+
+// Zygisk process flags
+pub const PROCESS_GRANTED_ROOT: u32 = 1 << 0;
+pub const PROCESS_ON_DENYLIST: u32 = 1 << 1;
+pub const PROCESS_IS_SYSUI: u32 = 1 << 31;

zygiskd/src/main.rs

@@ -3,10 +3,12 @@
 mod companion;
 mod constants;
 mod dl;
+mod root_impl;
 mod utils;
 mod watchdog;
 mod zygiskd;
 
+use anyhow::Result;
 use clap::{Subcommand, Parser};
 
 #[derive(Parser, Debug)]
@@ -35,19 +37,23 @@ fn init_android_logger(tag: &str) {
     );
 }
 
+fn start() -> Result<()> {
+    root_impl::setup()?;
+    let cli = Args::parse();
+    match cli.command {
+        Commands::Watchdog => watchdog::entry()?,
+        Commands::Daemon => zygiskd::entry()?,
+        Commands::Companion { fd } => companion::entry(fd)?,
+    };
+    Ok(())
+}
+
 fn main() {
     let process = std::env::args().next().unwrap();
     let nice_name = process.split('/').last().unwrap();
     init_android_logger(nice_name);
 
-    let cli = Args::parse();
-    let result = match cli.command {
-        Commands::Watchdog => watchdog::entry(),
-        Commands::Daemon => zygiskd::entry(),
-        Commands::Companion { fd } => companion::entry(fd),
-    };
-
-    if let Err(e) = &result {
+    if let Err(e) = start() {
         log::error!("Crashed: {}\n{}", e, e.backtrace());
     }
 }

zygiskd/src/root_impl/kernelsu.rs

@@ -0,0 +1,36 @@
+use anyhow::{bail, Result};
+use nix::libc::prctl;
+use crate::constants::{MIN_KSU_VERSION, MAX_KSU_VERSION};
+
+const KERNEL_SU_OPTION: i32 = 0xdeadbeefu32 as i32;
+
+const CMD_GET_VERSION: usize = 2;
+const CMD_GET_ALLOW_LIST: usize = 5;
+const CMD_GET_DENY_LIST: usize = 6;
+
+pub fn is_kernel_su() -> Result<bool> {
+    let mut version = 0;
+    unsafe { prctl(KERNEL_SU_OPTION, CMD_GET_VERSION, &mut version as *mut i32) };
+    return match version {
+        0 => Ok(false),
+        MIN_KSU_VERSION..=MAX_KSU_VERSION => Ok(true),
+        1..=MIN_KSU_VERSION => bail!("KernelSU version too old: {}", version),
+        _ => bail!("KernelSU version abnormal: {}", version)
+    }
+}
+
+pub fn uid_on_allowlist(uid: i32) -> bool {
+    let mut size = 1024u32;
+    let mut uids = vec![0; size as usize];
+    unsafe { prctl(KERNEL_SU_OPTION, CMD_GET_ALLOW_LIST, uids.as_mut_ptr(), &mut size as *mut u32) };
+    uids.resize(size as usize, 0);
+    uids.contains(&uid)
+}
+
+pub fn uid_on_denylist(uid: i32) -> bool {
+    let mut size = 1024u32;
+    let mut uids = vec![0; size as usize];
+    unsafe { prctl(KERNEL_SU_OPTION, CMD_GET_DENY_LIST, uids.as_mut_ptr(), &mut size as *mut u32) };
+    uids.resize(size as usize, 0);
+    uids.contains(&uid)
+}

zygiskd/src/root_impl/magisk.rs

@@ -0,0 +1,30 @@
+use anyhow::{bail, Result};
+use std::process::{Command, Stdio};
+use crate::constants::MIN_MAGISK_VERSION;
+
+pub fn is_magisk() -> Result<bool> {
+    let version: Option<i32> = Command::new("magisk")
+        .arg("-V")
+        .stdout(Stdio::piped())
+        .spawn().ok()
+        .and_then(|child| child.wait_with_output().ok())
+        .and_then(|output| String::from_utf8(output.stdout).ok())
+        .and_then(|output| output.trim().parse().ok());
+    if let Some(version) = version {
+        if version < MIN_MAGISK_VERSION {
+            bail!("Magisk version too old: {}", version);
+        }
+        return Ok(true);
+    }
+    Ok(false)
+}
+
+pub fn uid_on_allowlist(uid: i32) -> bool {
+    // TODO: uid_on_allowlist
+    return false;
+}
+
+pub fn uid_on_denylist(uid: i32) -> bool {
+    // TODO: uid_on_denylist
+    return false;
+}

zygiskd/src/root_impl/mod.rs

@@ -0,0 +1,40 @@
+mod kernelsu;
+mod magisk;
+
+use once_cell::sync::OnceCell;
+use anyhow::{bail, Result};
+
+enum RootImpl {
+    KernelSU,
+    Magisk,
+}
+
+static ROOT_IMPL: OnceCell<RootImpl> = OnceCell::new();
+
+pub fn setup() -> Result<()> {
+    if kernelsu::is_kernel_su()? {
+        if let Ok(true) = magisk::is_magisk() {
+            bail!("Multiple root implementation");
+        }
+        let _ = ROOT_IMPL.set(RootImpl::KernelSU);
+    } else if magisk::is_magisk()? {
+        let _ = ROOT_IMPL.set(RootImpl::Magisk);
+    } else {
+        bail!("Unknown root implementation");
+    }
+    Ok(())
+}
+
+pub fn uid_on_allowlist(uid: i32) -> bool {
+    match ROOT_IMPL.get().unwrap() {
+        RootImpl::KernelSU => kernelsu::uid_on_allowlist(uid),
+        RootImpl::Magisk => magisk::uid_on_allowlist(uid),
+    }
+}
+
+pub fn uid_on_denylist(uid: i32) -> bool {
+    match ROOT_IMPL.get().unwrap() {
+        RootImpl::KernelSU => kernelsu::uid_on_denylist(uid),
+        RootImpl::Magisk => magisk::uid_on_denylist(uid),
+    }
+}

zygiskd/src/utils.rs

@@ -40,6 +40,7 @@ pub trait UnixStreamExt {
     fn read_usize(&mut self) -> Result<usize>;
     fn read_string(&mut self) -> Result<String>;
     fn write_u8(&mut self, value: u8) -> Result<()>;
+    fn write_u32(&mut self, value: u32) -> Result<()>;
     fn write_usize(&mut self, value: usize) -> Result<()>;
     fn write_string(&mut self, value: &str) -> Result<()>;
 }
@@ -75,6 +76,11 @@ impl UnixStreamExt for UnixStream {
         Ok(())
     }
 
+    fn write_u32(&mut self, value: u32) -> Result<()> {
+        self.write_all(&value.to_ne_bytes())?;
+        Ok(())
+    }
+
     fn write_usize(&mut self, value: usize) -> Result<()> {
         self.write_all(&value.to_ne_bytes())?;
         Ok(())

zygiskd/src/zygiskd.rs

@@ -1,6 +1,6 @@
 use crate::constants::DaemonSocketAction;
 use crate::utils::UnixStreamExt;
-use crate::{constants, lp_select, utils};
+use crate::{constants, lp_select, root_impl, utils};
 use anyhow::{bail, Result};
 use memfd::Memfd;
 use nix::{
@@ -67,10 +67,10 @@ fn get_arch() -> Result<&'static str> {
     let output = Command::new("getprop").arg("ro.product.cpu.abi").output()?;
     let system_arch = String::from_utf8(output.stdout)?;
     if system_arch.contains("arm") {
-        return Ok(lp_select!("armeabi-v7a", "arm64-v8a"))
+        return Ok(lp_select!("armeabi-v7a", "arm64-v8a"));
     }
     if system_arch.contains("x86") {
-        return Ok(lp_select!("x86", "x86_64"))
+        return Ok(lp_select!("x86", "x86_64"));
     }
     bail!("Unsupported system architecture: {}", system_arch);
 }
@@ -93,7 +93,7 @@ fn load_modules(arch: &str) -> Result<Vec<Module>> {
             continue;
         }
         log::info!("  Loading module `{name}`...");
-        let memfd = match create_memfd(&name, &so_path) {
+        let memfd = match create_memfd(&so_path) {
             Ok(memfd) => memfd,
             Err(e) => {
                 log::warn!("  Failed to create memfd for `{name}`: {e}");
@@ -116,10 +116,9 @@ fn load_modules(arch: &str) -> Result<Vec<Module>> {
     Ok(modules)
 }
 
-fn create_memfd(name: &str, so_path: &PathBuf) -> Result<Memfd> {
+fn create_memfd(so_path: &PathBuf) -> Result<Memfd> {
     let opts = memfd::MemfdOptions::default().allow_sealing(true);
-    let memfd = opts.create(name)?;
-
+    let memfd = opts.create("jit-cache")?;
     let file = fs::File::open(so_path)?;
     let mut reader = std::io::BufReader::new(file);
     let mut writer = memfd.as_file();
@@ -193,6 +192,18 @@ fn handle_daemon_action(mut stream: UnixStream, context: &Context) -> Result<()>
         DaemonSocketAction::ReadNativeBridge => {
             stream.write_string(&context.native_bridge)?;
         }
+        DaemonSocketAction::GetProcessFlags => {
+            let uid = stream.read_u32()? as i32;
+            let mut flags = 0u32;
+            if root_impl::uid_on_allowlist(uid) {
+                flags |= constants::PROCESS_GRANTED_ROOT;
+            }
+            if root_impl::uid_on_denylist(uid) {
+                flags |= constants::PROCESS_ON_DENYLIST;
+            }
+            // TODO: PROCESS_IS_SYSUI?
+            stream.write_u32(flags)?;
+        }
         DaemonSocketAction::ReadModules => {
             stream.write_usize(context.modules.len())?;
             for module in context.modules.iter() {