network: implement TCP proxy NAT via smoltcp

network/bin/network.rs

@@ -1,3 +1,6 @@
+use std::str::FromStr;
+
+use advmac::MacAddr6;
 use anyhow::Result;
 use clap::Parser;
 use env_logger::Env;
@@ -10,13 +13,23 @@ struct NetworkArgs {
 
     #[arg(long, default_value = "fe80::1/10")]
     ipv6_network: String,
+
+    #[arg(long)]
+    force_mac_address: Option<String>,
 }
 
 #[tokio::main]
 async fn main() -> Result<()> {
     env_logger::Builder::from_env(Env::default().default_filter_or("warn")).init();
     let args = NetworkArgs::parse();
-    let mut service = NetworkService::new(args.ipv4_network, args.ipv6_network)?;
+
+    let force_mac_address = if let Some(mac_str) = args.force_mac_address {
+        Some(MacAddr6::from_str(&mac_str)?)
+    } else {
+        None
+    };
+
+    let mut service = NetworkService::new(args.ipv4_network, args.ipv6_network, force_mac_address)?;
     service.watch().await?;
     Ok(())
 }