Initial commit

zygisk-module/module.prop

@@ -0,0 +1,6 @@
+id=camera-hook-zygisk
+name=CamSwapper Zygisk Hook
+version=1.0
+versionCode=1
+author=CamSwapper
+description=Injects libcamera_hook.so into cameraserver via Zygisk

zygisk-module/zygisk_entry.cpp

@@ -0,0 +1,113 @@
+#include <cstdlib>
+#include <cstring>
+#include <cstdio>
+#include <dlfcn.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <pthread.h>
+#include <android/log.h>
+#include <sys/stat.h>
+#include <jni.h>
+
+#define LOG_TAG "CameraHookZygisk"
+#define ALOGI(...) __android_log_print(ANDROID_LOG_INFO, LOG_TAG, __VA_ARGS__)
+#define ALOGE(...) __android_log_print(ANDROID_LOG_ERROR, LOG_TAG, __VA_ARGS__)
+
+#define HOOK_LIB_PATH "/data/local/camera_magic/libcamera_hook.so"
+
+static void* g_hook_handle = nullptr;
+static bool g_hook_loaded = false;
+static bool g_in_zygote = false;
+
+static bool is_camera_process() {
+    char cmdline[256] = {0};
+    int fd = open("/proc/self/cmdline", O_RDONLY);
+    if (fd < 0) return false;
+    ssize_t n = read(fd, cmdline, sizeof(cmdline) - 1);
+    close(fd);
+    if (n <= 0) return false;
+    return (strstr(cmdline, "cameraserver") != nullptr ||
+            strstr(cmdline, "camera.provider") != nullptr ||
+            strstr(cmdline, "android.hardware.camera") != nullptr);
+}
+
+static void load_hook() {
+    if (g_hook_loaded) return;
+    g_hook_loaded = true;
+    struct stat st;
+    if (stat(HOOK_LIB_PATH, &st) != 0) {
+        ALOGE("Hook library not found: %s", HOOK_LIB_PATH);
+        return;
+    }
+    g_hook_handle = dlopen(HOOK_LIB_PATH, RTLD_NOW | RTLD_LOCAL);
+    if (!g_hook_handle) {
+        ALOGE("dlopen(%s) failed: %s", HOOK_LIB_PATH, dlerror());
+        return;
+    }
+    ALOGI("Hook library loaded in PID %d", getpid());
+}
+
+static void post_fork_child() {
+    if (is_camera_process()) {
+        ALOGI("Camera process detected (PID %d), loading hook", getpid());
+        load_hook();
+    }
+}
+
+__attribute__((constructor))
+static void zygisk_init() {
+    char cmdline[256] = {0};
+    int fd = open("/proc/self/cmdline", O_RDONLY);
+    if (fd >= 0) {
+        read(fd, cmdline, sizeof(cmdline) - 1);
+        close(fd);
+    }
+    if (strstr(cmdline, "zygote") || strstr(cmdline, "zygote64")) {
+        g_in_zygote = true;
+        ALOGI("Loaded in Zygote (PID %d), registering atfork", getpid());
+        pthread_atfork(nullptr, nullptr, post_fork_child);
+    } else if (is_camera_process()) {
+        ALOGI("Loaded directly in camera process (PID %d)", getpid());
+        load_hook();
+    }
+}
+
+extern "C" {
+
+__attribute__((visibility("default")))
+void zygisk_module_entry(void* api, JNIEnv* env) {
+    (void)api;
+    (void)env;
+}
+
+__attribute__((visibility("default")))
+void pre_app_specialize(void* module, void* args) {
+    (void)module;
+    (void)args;
+}
+
+__attribute__((visibility("default")))
+void post_app_specialize(void* module, const void* args) {
+    (void)module;
+    (void)args;
+    if (is_camera_process()) {
+        ALOGI("Camera app detected via post_app_specialize (PID %d)", getpid());
+        load_hook();
+    }
+}
+
+__attribute__((visibility("default")))
+void pre_server_specialize(void* module, void* args) {
+    (void)module;
+    (void)args;
+}
+
+__attribute__((visibility("default")))
+void post_server_specialize(void* module, const void* args) {
+    (void)module;
+    (void)args;
+    ALOGI("Server specialized (PID %d), loading hook", getpid());
+    load_hook();
+}
+
+}