From 3a72258df4143b91e3ea9a21ef558b390ec53ded Mon Sep 17 00:00:00 2001
From: snake-4 <18491360+snake-4@users.noreply.github.com>
Date: Fri, 3 May 2024 02:30:58 +0200
Subject: [PATCH] Added prop hiding

---
 .gitmodules                    |  3 ++
 module/jni/Android.mk          |  5 +--
 module/jni/include/modules.hpp |  1 +
 module/jni/main.cpp            |  4 +--
 module/jni/modules.cpp         | 60 +++++++++++++++++++++++++++++++++-
 module/jni/system_properties   |  1 +
 6 files changed, 69 insertions(+), 5 deletions(-)
 create mode 160000 module/jni/system_properties

diff --git a/.gitmodules b/.gitmodules
index df02122..b19adfd 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -4,3 +4,6 @@
 [submodule "module/jni/libcxx"]
 	path = module/jni/libcxx
 	url = https://github.com/topjohnwu/libcxx.git
+[submodule "module/jni/system_properties"]
+	path = module/jni/system_properties
+	url = https://github.com/topjohnwu/system_properties
diff --git a/module/jni/Android.mk b/module/jni/Android.mk
index 0d3c95f..7d86b01 100644
--- a/module/jni/Android.mk
+++ b/module/jni/Android.mk
@@ -4,8 +4,9 @@ include $(CLEAR_VARS)
 LOCAL_C_INCLUDES := $(LOCAL_PATH)/include $(LOCAL_PATH)/elfio
 LOCAL_MODULE := zygisk
 LOCAL_SRC_FILES := utils.cpp map_parser.cpp mountinfo_parser.cpp modules.cpp main.cpp
-LOCAL_STATIC_LIBRARIES := libcxx
+LOCAL_STATIC_LIBRARIES := libcxx libsystemproperties
 LOCAL_LDLIBS := -llog
 include $(BUILD_SHARED_LIBRARY)
 
-include jni/libcxx/Android.mk
\ No newline at end of file
+include jni/libcxx/Android.mk
+include jni/system_properties/Android.mk
\ No newline at end of file
diff --git a/module/jni/include/modules.hpp b/module/jni/include/modules.hpp
index be24108..891d8b1 100644
--- a/module/jni/include/modules.hpp
+++ b/module/jni/include/modules.hpp
@@ -3,3 +3,4 @@
 void doUnmount();
 void doRemount();
 void doHideZygisk();
+void doMrProp();
diff --git a/module/jni/main.cpp b/module/jni/main.cpp
index 285d91c..99e5d65 100644
--- a/module/jni/main.cpp
+++ b/module/jni/main.cpp
@@ -113,9 +113,8 @@ class ZygiskModule : public zygisk::ModuleBase
                 LOGD("Invoking the companion was successful.");
             else
             {
-                LOGW("Invoking the companion failed. Performing operations in Zygote context!");
+                LOGW("Invoking the companion failed. Functionality will be limited in Zygote context!");
                 doUnmount();
-                doRemount();
             }
 
             doHideZygisk();
@@ -165,6 +164,7 @@ void zygisk_companion_handler(int fd)
             {
                 doUnmount();
                 doRemount();
+                doMrProp();
             }));
     }();
 
diff --git a/module/jni/modules.cpp b/module/jni/modules.cpp
index 4c820f8..19f1b82 100644
--- a/module/jni/modules.cpp
+++ b/module/jni/modules.cpp
@@ -1,10 +1,18 @@
 #include <string>
+#include <string_view>
 #include <set>
+#include <atomic>
 #include <unordered_map>
 #include <cstdint>
 #include <sys/mount.h>
 #include <elfio/elfio.hpp>
 
+// These includes are from the system_properties submodule, not NDK!
+#define _REALLY_INCLUDE_SYS__SYSTEM_PROPERTIES_H_
+#include <api/system_properties.h>
+#include <api/_system_properties.h>
+#include <system_properties/prop_info.h>
+
 #include "zygisk.hpp"
 #include "logging.hpp"
 #include "map_parser.hpp"
@@ -45,7 +53,7 @@ static bool shouldUnmount(const mountinfo_entry_t &mount, const mountinfo_root_r
     if (type == "overlay")
     {
         const auto &options = mount.getSuperOptions();
-        
+
         if (options.contains("lowerdir") && options.at("lowerdir").starts_with("/data/adb"))
             return true;
 
@@ -159,3 +167,53 @@ void doHideZygisk()
         LOGD("libnativebridge.so had_error was reset.");
     }
 }
+
+void doMrProp()
+{
+    static bool isInitialized = false;
+    static int resetCount = 0;
+    if (!isInitialized)
+    {
+        isInitialized = __system_properties_init() == 0;
+    }
+
+    if (!isInitialized)
+    {
+        LOGE("Could not initialize system_properties!");
+        return;
+    }
+
+    int ret = __system_property_foreach(
+        [](const prop_info *pi, void *)
+        {
+            if (std::string_view(pi->name).starts_with("ro.") && !pi->is_long())
+            {
+                auto serial = std::atomic_load_explicit(&pi->serial, std::memory_order_relaxed);
+
+                // Well this is a bit dangerous
+                bool shouldReset = (serial & 0xFF) != 0;
+                auto length = strlen(pi->value);
+
+                if (!shouldReset)
+                {
+                    for (size_t i = length; i < PROP_VALUE_MAX; i++)
+                    {
+                        if (pi->value[i] != 0)
+                        {
+                            shouldReset = true;
+                            break;
+                        }
+                    }
+                }
+
+                if (shouldReset)
+                {
+                    resetCount++;
+                    __system_property_update(const_cast<prop_info *>(pi), pi->value, length);
+                }
+            }
+        },
+        nullptr);
+
+    LOGD("__system_property_foreach returned %d. resetCount=%d", ret, resetCount);
+}
\ No newline at end of file
diff --git a/module/jni/system_properties b/module/jni/system_properties
new file mode 160000
index 0000000..e1a3e77
--- /dev/null
+++ b/module/jni/system_properties
@@ -0,0 +1 @@
+Subproject commit e1a3e77d2376be2ba747baa7ba16b34554b14956