big changes

common/src/crypto/salt_pair.rs

@@ -0,0 +1,40 @@
+use aead::{rand_core::RngCore, OsRng};
+
+pub struct SaltPair {
+    local_salt: [u8; 32],
+    remote_salt: [u8; 32],
+    is_initiator: bool,
+}
+
+impl SaltPair {
+    pub fn new(is_initiator: bool) -> Self {
+        let mut local_salt = [0u8; 32];
+        OsRng.fill_bytes(&mut local_salt);
+        Self {
+            local_salt,
+            remote_salt: [0; 32],
+            is_initiator,
+        }
+    }
+
+    pub fn get_local(&self) -> [u8; 32] {
+        self.local_salt
+    }
+
+    pub fn set_remote_salt(&mut self, salt: [u8; 32]) {
+        self.remote_salt = salt
+    }
+
+    pub fn get_total(&self) -> [u8; 64] {
+        let mut salt = [0u8; 64];
+        if self.is_initiator {
+            salt[..32].copy_from_slice(&self.local_salt);
+            salt[32..].copy_from_slice(&self.remote_salt);
+            salt
+        } else {
+            salt[..32].copy_from_slice(&self.remote_salt);
+            salt[32..].copy_from_slice(&self.local_salt);
+            salt
+        }
+    }
+}