From a2d25820985b04f15f3c0f38cabfd7130124d943 Mon Sep 17 00:00:00 2001
From: darkgallium <florian+git@aloneinthedark.xyz>
Date: Fri, 22 May 2020 18:51:46 +0200
Subject: [PATCH] add better error handling

---
 src/fw.rs | 40 ++++++++++++++++++++++++++++------------
 1 file changed, 28 insertions(+), 12 deletions(-)

diff --git a/src/fw.rs b/src/fw.rs
index 07282af..7650b3a 100644
--- a/src/fw.rs
+++ b/src/fw.rs
@@ -1,6 +1,8 @@
 use iptables;
 use regex::Regex;
 use std::collections::HashSet;
+use std::io;
+
 
 #[derive(PartialEq,Eq,Debug,Hash)]
 pub struct Port {
@@ -8,22 +10,35 @@ pub struct Port {
     number: u16,
 }
 
-pub fn setup(ipt: &iptables::IPTables) {
-    ipt.new_chain("filter", "DIPLONAT").unwrap();
-    ipt.insert("filter", "INPUT", "-j DIPLONAT", 1).unwrap();
+#[derive(Debug)]
+pub struct FirewallError(String);
+
+impl From<iptables::error::IPTError> for FirewallError {
+    fn from(error: iptables::error::IPTError) -> Self {
+        FirewallError(error.to_string())
+    }
+
 }
 
-pub fn open_ports(ipt: &iptables::IPTables, ports: Vec<Port>) {
+pub fn setup(ipt: &iptables::IPTables) -> Result<(), FirewallError> {
+    ipt.new_chain("filter", "DIPLONAT")?;
+    ipt.insert("filter", "INPUT", "-j DIPLONAT", 1)?;
+    Ok(())
+}
+
+pub fn open_ports(ipt: &iptables::IPTables, ports: Vec<Port>) -> Result<(), FirewallError> {
 
     for p in ports {
-        ipt.append("filter", "DIPLONAT", &format!("-p {} --dport {} -j ACCEPT", p.proto, p.number)).unwrap();
+        ipt.append("filter", "DIPLONAT", &format!("-p {} --dport {} -j ACCEPT", p.proto, p.number))?;
     }
+
+    Ok(())
 }
 
-pub fn get_opened_ports(ipt: &iptables::IPTables) -> HashSet<Port> {
+pub fn get_opened_ports(ipt: &iptables::IPTables) -> Result<HashSet<Port>, FirewallError> {
     let mut opened_ports: HashSet<Port> = HashSet::new();
 
-    let list = ipt.list("filter", "DIPLONAT").unwrap();
+    let list = ipt.list("filter", "DIPLONAT")?;
     let re = Regex::new(r"\-A.*? \-p (\w+).*\-\-dport (\d+).*?\-j ACCEPT").unwrap();
     for i in list {
         let caps = re.captures(&i);
@@ -41,13 +56,14 @@ pub fn get_opened_ports(ipt: &iptables::IPTables) -> HashSet<Port> {
         }
     }
 
-    opened_ports
+    Ok(opened_ports)
 }
 
-pub fn cleanup(ipt: &iptables::IPTables) {
-    ipt.flush_chain("filter", "DIPLONAT").unwrap();
-    ipt.delete("filter", "INPUT", "-j DIPLONAT").unwrap();
-    ipt.delete_chain("filter", "DIPLONAT").unwrap();
+pub fn cleanup(ipt: &iptables::IPTables) -> Result<(), FirewallError> {
+    ipt.flush_chain("filter", "DIPLONAT")?;
+    ipt.delete("filter", "INPUT", "-j DIPLONAT")?;
+    ipt.delete_chain("filter", "DIPLONAT")?;
+    Ok(())
 }
 
 /*