ensure chain jump is added only once

Cargo.lock

@@ -1210,9 +1210,9 @@ dependencies = [
 
 [[package]]
 name = "tokio"
-version = "0.2.11"
+version = "0.2.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8fdd17989496f49cdc57978c96f0c9fe5e4a58a8bddc6813c449a4624f6a030b"
+checksum = "d099fa27b9702bed751524694adbe393e18b36b204da91eb1cbbbbb4a5ee2d58"
 dependencies = [
  "bytes 0.5.4",
  "fnv",

Cargo.toml

@@ -11,7 +11,7 @@ reqwest = { version = "0.10", features = ["json"] }
 igd = { version = "0.10.0", features = ["aio"] }
 log = "0.4"
 pretty_env_logger = "0.4"
-tokio = "0.2.11"
+tokio = "0.2"
 futures = "0.3.5"
 serde = { version = "1.0.107", features = ["derive"] }
 serde_json = "1.0.53"

src/diplonat.rs

@@ -1,5 +1,4 @@
 use anyhow::Result;
-use log::*;
 use tokio::try_join;
 use crate::consul_actor::ConsulActor;
 use crate::igd_actor::IgdActor;

src/fw.rs

@@ -1,7 +1,6 @@
 use iptables;
 use regex::Regex;
 use std::collections::HashSet;
-use std::io;
 use crate::messages;
 
 #[derive(Debug)]
@@ -14,15 +13,17 @@ impl From<iptables::error::IPTError> for FirewallError {
 }
 
 pub fn setup(ipt: &iptables::IPTables) -> Result<(), FirewallError> {
-    
-    ipt.new_chain("filter", "DIPLONAT")?;
-    ipt.insert("filter", "INPUT", "-j DIPLONAT", 1)?;
+
+    if !ipt.chain_exists("filter", "DIPLONAT")? {
+        ipt.new_chain("filter", "DIPLONAT")?;
+    }
+
+    ipt.insert_unique("filter", "INPUT", "-j DIPLONAT", 1)?;
 
     Ok(())
 }
 
 pub fn open_ports(ipt: &iptables::IPTables, ports: messages::PublicExposedPorts) -> Result<(), FirewallError> {
-
     for p in ports.tcp_ports {
         ipt.append("filter", "DIPLONAT", &format!("-p tcp --dport {} -j ACCEPT", p))?;
     }

src/fw_actor.rs

@@ -1,8 +1,4 @@
-use igd::aio::*;
-use igd::PortMappingProtocol;
-use std::net::SocketAddrV4;
-use log::*;
-use anyhow::{Result, Context};
+use anyhow::Result;
 use tokio::{
   select, 
   sync::watch, 
@@ -10,6 +6,7 @@ use tokio::{
     self, 
     Duration
 }};
+use log::*;
 
 use iptables;
 use crate::messages;
@@ -17,7 +14,7 @@ use crate::fw;
 use std::collections::HashSet;
 
 pub struct FirewallActor {
-  ipt: iptables::IPTables,
+  pub ipt: iptables::IPTables,
   rx_ports: watch::Receiver<messages::PublicExposedPorts>,
   last_ports: messages::PublicExposedPorts,
   refresh: Duration
@@ -25,8 +22,6 @@ pub struct FirewallActor {
 
 impl FirewallActor {
   pub async fn new(_refresh: Duration, rxp: &watch::Receiver<messages::PublicExposedPorts>) -> Result<Self> {
-
-    
     let ctx = Self { 
       ipt: iptables::new(false).unwrap(),
       rx_ports: rxp.clone(),
@@ -61,7 +56,6 @@ impl FirewallActor {
   }
 
   pub async fn do_fw_update(&self) -> Result<()> {
-    
     let curr_opened_ports = fw::get_opened_ports(&self.ipt).unwrap();
 
     let diff_tcp = self.last_ports.tcp_ports.difference(&curr_opened_ports.tcp_ports).copied().collect::<HashSet<u16>>();

src/main.rs

@@ -7,7 +7,6 @@ mod diplonat;
 mod fw;
 mod fw_actor;
 
-use iptables;
 use log::*;
 use diplonat::Diplonat;