baesd ruste crypto?!!?1'1??!?!!?!?

src/lib.rs

@@ -0,0 +1,68 @@
+use wasm_bindgen::prelude::*;
+
+use js_sys::Uint8Array;
+
+use blowfish::Blowfish;
+use aes::Aes128;
+use block_modes::{BlockMode, Cbc, Ecb};
+use block_modes::block_padding::{NoPadding, ZeroPadding};
+use md5::{Md5, Digest};
+
+type BfCbc = Cbc<Blowfish, NoPadding>;
+type Aes128Ecb = Ecb<Aes128, ZeroPadding>;
+
+const TRACK_CDN_KEY: [u8; 16] = [106, 111, 54, 97, 101, 121, 54, 104, 97, 105, 100, 50, 84, 101, 105, 104];
+const BF_SECRET: [u8; 16] = [103, 52, 101, 108, 53, 56, 119, 99, 48, 122, 118, 102, 57, 110, 97, 49];
+
+#[wasm_bindgen]
+pub struct Cipher {
+    cipher: BfCbc
+}
+
+#[wasm_bindgen]
+impl Cipher {
+    #[wasm_bindgen(constructor)]
+    pub fn new(id: &str) -> Self {
+        let id_md5 = format!("{:x}", Md5::digest(id.as_bytes()));
+        let id_md5 = id_md5.as_bytes();
+        let mut key = [0u8; 16];
+        for i in 0..16 {
+            key[i] = id_md5[i] ^ id_md5[i+16] ^ BF_SECRET[i]
+        };
+        Self { cipher: BfCbc::new_from_slices(&key, &[0, 1, 2, 3, 4, 5, 6, 7]).unwrap() }
+    }
+
+    pub fn decrypt_chunk(&self, chunk: &mut [u8]) -> Uint8Array {
+        let chunk = self.cipher.clone().decrypt(chunk).unwrap();
+        unsafe { Uint8Array::view(&chunk) }
+    }
+}
+
+#[wasm_bindgen]
+pub fn stream_url(md5_origin: &str, format: &str, id: i32, media_version: u8) -> String {
+    // md5 origin + format num + id + media version
+    let metadata = [
+        md5_origin.as_bytes(),
+        &[b'\xa4'],
+        format.as_bytes(),
+        &[b'\xa4'],
+        id.to_string().as_bytes(),
+        &[b'\xa4'],
+        media_version.to_string().as_bytes(),
+    ].concat();
+
+    let hash = format!("{:x}", Md5::digest(&metadata));
+
+    // md5 hash + previous metadata
+    let metadata_hash = [
+        hash.as_bytes(),
+        &[b'\xa4'],
+        &metadata,
+        &[b'\xa4'],
+    ].concat();
+
+    let cipher = Aes128Ecb::new_from_slices(&TRACK_CDN_KEY, Default::default()).unwrap();
+    let ciphertext = cipher.encrypt_vec(&metadata_hash);
+
+    format!("https://cdns-proxy-{}.dzcdn.net/mobile/1/{}", md5_origin.chars().next().unwrap(), hex::encode(ciphertext))
+}