things

prudpv0/src/crypto/friends_insecure.rs

@@ -0,0 +1,52 @@
+use std::rc::Rc;
+
+use hmac::Mac;
+use rc4::{KeyInit, Rc4, StreamCipher};
+use rnex_core::prudp::encryption::{DEFAULT_KEY, EncryptionPair};
+use typenum::U5;
+
+use crate::crypto::{
+    Crypto, CryptoInstance,
+    common_crypto::common_checksum,
+    friends_common::{ACCESS_KEY, HmacMd5},
+};
+
+pub struct InsecureInstance {
+    pair: EncryptionPair<Rc4<U5>>,
+}
+
+impl CryptoInstance for InsecureInstance {
+    fn decrypt_incoming(&mut self, data: &mut [u8]) {
+        self.pair.recv.apply_keystream(data);
+    }
+    fn encrypt_outgoing(&mut self, data: &mut [u8]) {
+        self.pair.send.apply_keystream(data);
+    }
+    fn get_user_id(&self) -> u32 {
+        0
+    }
+    fn generate_signature(&self, data: &[u8]) -> [u8; 4] {
+        let mut hmac = <HmacMd5 as Mac>::new_from_slice(ACCESS_KEY.as_bytes())
+            .expect("unable to create hmac md5");
+        hmac.update(data);
+        hmac.finalize().into_bytes()[0..4].try_into().unwrap()
+    }
+}
+
+pub struct Insecure();
+
+impl Crypto for Insecure {
+    type Instance = InsecureInstance;
+    fn new() -> Self {
+        Self()
+    }
+    fn calculate_checksum(&self, data: &[u8]) -> u8 {
+        common_checksum(ACCESS_KEY, data)
+    }
+
+    fn instantiate(&self, packet_data: &[u8]) -> Self::Instance {
+        InsecureInstance {
+            pair: EncryptionPair::init_both(|| Rc4::new(&DEFAULT_KEY)),
+        }
+    }
+}