From 695c8bc5d0a4b3d22938e3661f54b9abc8b1b396 Mon Sep 17 00:00:00 2001
From: topjohnwu <topjohnwu@gmail.com>
Date: Tue, 17 Dec 2019 16:38:12 -0500
Subject: [PATCH] Detect package name for copying binaries

Close #2152
---
 native/jni/core/bootstages.cpp | 22 +++++++++++-----------
 native/jni/core/db.cpp         | 27 ++++++++++++++++++++-------
 native/jni/include/db.h        |  3 ++-
 3 files changed, 33 insertions(+), 19 deletions(-)

diff --git a/native/jni/core/bootstages.cpp b/native/jni/core/bootstages.cpp
index 6c1ba2175..c0424a2ea 100644
--- a/native/jni/core/bootstages.cpp
+++ b/native/jni/core/bootstages.cpp
@@ -317,13 +317,15 @@ static int bind_mount(const char *from, const char *to, bool log) {
 static bool magisk_env() {
 	LOGI("* Initializing Magisk environment\n");
 
+	string pkg;
+	check_manager(&pkg);
+
+	char install_dir[128];
+	sprintf(install_dir, "%s/0/%s/install", APP_DATA_DIR, pkg.data());
+
 	// Alternative binaries paths
-	constexpr const char *alt_bin[] = {
-		"/cache/data_adb/magisk", "/data/magisk",
-		"/data/data/com.topjohnwu.magisk/install",
-		"/data/user_de/0/com.topjohnwu.magisk/install"
-	};
-	for (auto &alt : alt_bin) {
+	const char *alt_bin[] = { "/cache/data_adb/magisk", "/data/magisk", install_dir };
+	for (auto alt : alt_bin) {
 		struct stat st;
 		if (lstat(alt, &st) != -1) {
 			if (S_ISLNK(st.st_mode)) {
@@ -781,11 +783,9 @@ void boot_complete(int client) {
 		rename(MANAGERAPK, "/data/magisk.apk");
 		install_apk("/data/magisk.apk");
 	} else {
-		// Check whether we have a valid manager installed
-		db_strings str;
-		get_db_strings(str, SU_MANAGER);
-		if (validate_manager(str[SU_MANAGER], 0, nullptr)) {
-			// There is no manager installed, install the stub
+		// Check whether we have manager installed
+		if (!check_manager()) {
+			// Install stub
 			exec_command_sync("/sbin/magiskinit", "-x", "manager", "/data/magisk.apk");
 			install_apk("/data/magisk.apk");
 		}
diff --git a/native/jni/core/db.cpp b/native/jni/core/db.cpp
index c644e0b7e..910362d40 100644
--- a/native/jni/core/db.cpp
+++ b/native/jni/core/db.cpp
@@ -246,28 +246,41 @@ int get_uid_policy(su_access &su, int uid) {
 	return 0;
 }
 
-int validate_manager(string &alt_pkg, int userid, struct stat *st) {
+bool check_manager(string *pkg) {
+	db_strings str;
+	get_db_strings(str, SU_MANAGER);
+	bool ret = validate_manager(str[SU_MANAGER], 0, nullptr);
+	if (pkg) {
+		if (ret)
+			pkg->swap(str[SU_MANAGER]);
+		else
+			*pkg = "xxx";  /* Make sure the return pkg can never exist */
+	}
+	return ret;
+}
+
+bool validate_manager(string &pkg, int userid, struct stat *st) {
 	struct stat tmp_st;
 	if (st == nullptr)
 		st = &tmp_st;
 
 	// Prefer DE storage
 	char app_path[128];
-	sprintf(app_path, "%s/%d/%s", APP_DATA_DIR, userid, alt_pkg.empty() ? "xxx" : alt_pkg.data());
-	if (stat(app_path, st)) {
+	sprintf(app_path, "%s/%d/%s", APP_DATA_DIR, userid, pkg.data());
+	if (pkg.empty() || stat(app_path, st)) {
 		// Check the official package name
 		sprintf(app_path, "%s/%d/" JAVA_PACKAGE_NAME, APP_DATA_DIR, userid);
 		if (stat(app_path, st)) {
 			LOGE("su: cannot find manager");
 			memset(st, 0, sizeof(*st));
-			alt_pkg.clear();
-			return 1;
+			pkg.clear();
+			return false;
 		} else {
 			// Switch to official package if exists
-			alt_pkg = JAVA_PACKAGE_NAME;
+			pkg = JAVA_PACKAGE_NAME;
 		}
 	}
-	return 0;
+	return true;
 }
 
 void exec_sql(int client) {
diff --git a/native/jni/include/db.h b/native/jni/include/db.h
index 7b5726e0a..29614a249 100644
--- a/native/jni/include/db.h
+++ b/native/jni/include/db.h
@@ -155,7 +155,8 @@ typedef std::function<bool(db_row&)> db_row_cb;
 int get_db_settings(db_settings &cfg, int key = -1);
 int get_db_strings(db_strings &str, int key = -1);
 int get_uid_policy(su_access &su, int uid);
-int validate_manager(std::string &alt_pkg, int userid, struct stat *st);
+bool check_manager(std::string *pkg = nullptr);
+bool validate_manager(std::string &pkg, int userid, struct stat *st);
 void exec_sql(int client);
 char *db_exec(const char *sql);
 char *db_exec(const char *sql, const db_row_cb &fn);