use sha256 as function encrypt key

Cargo.toml

@@ -11,4 +11,5 @@ anyhow = "1.0.86"
 clap = { version = "4.5.3", features = ["derive"] }
 memmap2 = "0.9.4"
 rust-crypto = "0.2.36"
+sha2 = "0.10.8"
 thiserror = "1.0.63"

src/obfus.rs

@@ -323,16 +323,10 @@ impl Obfuscator {
     }
 
     pub fn encrypt_function_name(&mut self, function: &str, key: &str) -> crate::error::Result<()> {
-        let mut key_bytes = [0; 32];
-        if key.len() > 32 {
-            return Err(crate::error::Error::InvalidOption(
-                "key length must be less than 32",
-            ));
-        }
-        for (i, byte) in key.bytes().enumerate() {
-            key_bytes[i] = byte;
-        }
-        let encryptor = crypto::aessafe::AesSafe256Encryptor::new(&key_bytes);
+        use sha2::digest::Digest as _;
+
+        let hash = sha2::Sha256::digest(key.as_bytes());
+        let encryptor = crypto::aessafe::AesSafe256Encryptor::new(&hash);
 
         let tmp_file = std::fs::OpenOptions::new()
             .read(true)