diff --git a/include/utils/assets.h b/include/utils/assets.h
index 5e1b47b..cf75abf 100644
--- a/include/utils/assets.h
+++ b/include/utils/assets.h
@@ -12,4 +12,10 @@ void assets_load(assets *info);
 
 void assets_extract();
 
+// RUST DEMO START
+
+void rust_test(const char *const *ptr);
+
+// RUST DEMO END
+
 #endif
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index afa07b3..6db7fa3 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -9,6 +9,9 @@ include_directories(${PROJECT_SOURCE_DIR}/include/loader)
 
 link_directories(${PROJECT_SOURCE_DIR}/src/to-json/target/release)
 
+# TODO: just for test
+link_directories(${PROJECT_SOURCE_DIR}/src/assets/target/debug)
+
 add_subdirectory(utils)
 add_subdirectory(applet)
 add_subdirectory(bcrypt)
@@ -17,3 +20,6 @@ add_subdirectory(loader)
 
 add_executable(cleardns cleardns.c)
 target_link_libraries(cleardns utils applet bcrypt common loader)
+
+# TODO: just for test
+target_link_libraries(cleardns assets)
diff --git a/src/assets/Cargo.lock b/src/assets/Cargo.lock
index da04665..5e23ef0 100644
--- a/src/assets/Cargo.lock
+++ b/src/assets/Cargo.lock
@@ -251,12 +251,6 @@ version = "0.3.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ec90ff4d0fe1f57d600049061dc6bb68ed03c7d2fbd697274c41805dcb3f8608"
 
-[[package]]
-name = "futures-io"
-version = "0.3.26"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bfb8371b6fb2aeb2d280374607aeabfc99d95c72edfe51692e42d3d7f0d08531"
-
 [[package]]
 name = "futures-sink"
 version = "0.3.26"
@@ -276,12 +270,9 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9c1d6de3acfef38d2be4b1f543f553131788603495be83da675e180c8d6b7bd1"
 dependencies = [
  "futures-core",
- "futures-io",
  "futures-task",
- "memchr",
  "pin-project-lite",
  "pin-utils",
- "slab",
 ]
 
 [[package]]
diff --git a/src/assets/Cargo.toml b/src/assets/Cargo.toml
index 83999fa..761f136 100644
--- a/src/assets/Cargo.toml
+++ b/src/assets/Cargo.toml
@@ -3,10 +3,13 @@ name = "assets"
 version = "0.1.0"
 edition = "2021"
 
+[lib]
+crate-type = ["staticlib"]
+
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
 env_logger = "0.10.0"
 log = "0.4.17"
-reqwest = { version = "0.11.14", features = ["blocking", "deflate", "gzip", "brotli"] }
+reqwest = { version = "0.11.14", features = ["deflate", "gzip", "brotli"] }
 tokio = { version = "1.26.0", features = ["macros", "rt-multi-thread"] }
diff --git a/src/assets/cbindgen.toml b/src/assets/cbindgen.toml
new file mode 100644
index 0000000..cb8d3fd
--- /dev/null
+++ b/src/assets/cbindgen.toml
@@ -0,0 +1,3 @@
+language = "C"
+pragma_once = true
+include_version = true
diff --git a/src/assets/src/main.rs b/src/assets/src/fetch.rs
similarity index 60%
rename from src/assets/src/main.rs
rename to src/assets/src/fetch.rs
index 73381ba..a015399 100644
--- a/src/assets/src/main.rs
+++ b/src/assets/src/fetch.rs
@@ -1,17 +1,18 @@
-use std::collections::{HashMap, HashSet};
-use reqwest::Client;
-use std::env::set_var;
-use std::time::Duration;
-
 use std::fs::File;
 use std::io::Read;
+use reqwest::Client;
 use std::path::PathBuf;
-
+use std::time::Duration;
 use log::{debug, info, warn};
-
-const TIMEOUT: u64 = 60;
-
-const ASSETS_DIR: &str = "/cleardns/assets/";
+use std::collections::HashSet;
+
+#[derive(Debug)]
+pub(crate) struct Asset {
+    pub(crate) name: String,
+    pub(crate) timeout: u64,
+    pub(crate) workdir: String, // assets folder
+    pub(crate) sources: Vec<String>, // http url or file path
+}
 
 /// Cut text line by line and remove invisible characters on both sides.
 fn asset_tidy(data: &str) -> Vec<String> {
@@ -54,10 +55,10 @@ async fn http_fetch(url: &str, timeout: u64) -> Result<Vec<String>, String> {
 }
 
 /// Read the specified text file and organize it into a String array.
-async fn local_fetch(path: &str) -> Result<Vec<String>, String> {
+async fn local_fetch(path: &str, workdir: &str) -> Result<Vec<String>, String> {
     let mut path = String::from(path);
     if !path.starts_with("/") { // relative path
-        let file_path = PathBuf::from(ASSETS_DIR).join(path);
+        let file_path = PathBuf::from(workdir).join(path);
         path = String::from(file_path.to_str().unwrap());
     }
     match File::open(&path) {
@@ -74,16 +75,16 @@ async fn local_fetch(path: &str) -> Result<Vec<String>, String> {
 }
 
 /// Get multiple resource data and merge them.
-async fn asset_fetch(name: &str, sources: Vec<&str>) -> Vec<String> {
+pub(crate) async fn asset_fetch(info: &Asset) -> Vec<String> {
     let is_remote = |src: &str| {
         src.starts_with("http://") || src.starts_with("https://")
     };
     let mut contents: Vec<Vec<String>> = vec![];
-    for source in sources {
-        contents.push(match if is_remote(source) {
-            http_fetch(source.trim(), TIMEOUT).await
+    for source in &info.sources {
+        contents.push(match if is_remote(&source) {
+            http_fetch(source.trim(), info.timeout).await
         } else {
-            local_fetch(source.trim()).await
+            local_fetch(source.trim(), &info.workdir).await
         } {
             Ok(data) => {
                 debug!("Asset source `{}` fetch success with {} items", source.trim(), data.len());
@@ -99,62 +100,6 @@ async fn asset_fetch(name: &str, sources: Vec<&str>) -> Vec<String> {
         .into_iter()
         .flatten()
         .collect::<Vec<String>>());
-    info!("Asset `{}` fetch complete with {} items", name, contents.len());
+    info!("Asset `{}` fetch complete with {} items", info.name, contents.len());
     contents
 }
-
-async fn demo() {
-
-    println!("demo function start");
-
-    // match asset_fetch("https://res.343.re/Share/cleardns/gfwlist.txt", TIMEOUT).await {
-    //     Ok(data) => {
-    //         println!("{:?}", data);
-    //     },
-    //     Err(err) => println!("error -> {}", err)
-    // }
-
-    match local_fetch("../../tmp/gfwlist.txt").await {
-        Ok(data) => {
-            // println!("{:?}", data);
-        },
-        Err(err) => println!("error -> `{}`", err)
-    };
-
-    println!("demo function exit");
-
-}
-
-#[tokio::main]
-async fn main() {
-
-    set_var("RUST_LOG", "trace");
-    env_logger::init();
-
-    let d = vec![
-        "https://res.343.re/Share/cleardns/gfwlist.txt",
-        "/tmp/gfwlist.txt",
-    ];
-    asset_fetch("test", d).await;
-
-    // let demo = vec![
-    //     "baidu.com",
-    //     "ip.343.re",
-    //     "qq.com",
-    //     "google.com",
-    //     "res.343.re",
-    //     "ip.343.re",
-    //     "343.re",
-    // ];
-    // let demo = demo.into_iter()
-    //     .map(|x| String::from(x))
-    //     .collect();
-    // remove_dup(&demo);
-
-    // let data: &str = "dnomd343\n linjucong\n\nfuck\t\n7700\n";
-    // println!("{}", data);
-    // tidy(data);
-
-    println!("end demo");
-
-}
diff --git a/src/assets/src/lib.rs b/src/assets/src/lib.rs
new file mode 100644
index 0000000..ac11b25
--- /dev/null
+++ b/src/assets/src/lib.rs
@@ -0,0 +1,65 @@
+// mod fetch;
+//
+// use std::env::set_var;
+//
+// use crate::fetch::Asset;
+
+use std::ffi::{c_char, CStr};
+
+// const TIMEOUT: u64 = 60;
+//
+// const ASSETS_DIR: &str = "/cleardns/assets/";
+
+#[no_mangle]
+pub unsafe extern "C" fn rust_test(ptr: *const *const c_char) {
+    println!("enter rust function");
+
+    unsafe {
+
+        println!("ptr: {:?}", ptr);
+
+
+        let mut index = 0;
+        while *ptr.offset(index) != std::ptr::null() {
+
+            let p = *ptr.offset(index);
+
+            println!("loop: {:?}", p);
+
+            let s = String::from(
+                CStr::from_ptr(p).to_str().unwrap()
+            );
+
+            println!("content: {}", s);
+
+            index += 1;
+        }
+
+
+    }
+
+    println!("exit rust function");
+}
+
+// #[tokio::main]
+// async fn main() {
+//
+//     set_var("RUST_LOG", "trace");
+//     env_logger::init();
+//
+//     let d = vec![
+//         String::from("https://res.343.re/Share/cleardns/gfwlist.txt"),
+//         String::from("/tmp/gfwlist.txt"),
+//     ];
+//     let info = Asset {
+//         name: String::from("demo"),
+//         timeout: TIMEOUT,
+//         workdir: String::from(ASSETS_DIR),
+//         sources: d,
+//     };
+//     fetch::asset_fetch(&info).await;
+//
+//
+//     println!("end demo");
+//
+// }
diff --git a/src/cleardns.c b/src/cleardns.c
index 31c85a3..1225691 100644
--- a/src/cleardns.c
+++ b/src/cleardns.c
@@ -118,6 +118,28 @@ void cleardns() { // cleardns service
 }
 
 int main(int argc, char *argv[]) {
+
+    char **demo = string_list_init();
+    string_list_append(&demo, "item 1");
+    string_list_append(&demo, "item 2");
+    string_list_append(&demo, "item 3");
+
+    char *tmp = string_list_dump(demo);
+    log_warn("dump -> %s", tmp);
+
+    string_list_free(demo);
+
+    log_info("string list -> %p", demo);
+    log_info("string list 1 -> %p", demo[0]);
+    log_info("string list 2 -> %p", demo[1]);
+    log_info("string list 3 -> %p", demo[2]);
+    log_info("string list 4 -> %p", demo[3]);
+
+    rust_test(demo);
+
+    log_warn("test end");
+    exit(0);
+
     init(argc, argv);
     log_info("ClearDNS server start (%s)", VERSION);
     cleardns();