From 4f4b6b048d53f3c4c9cc2437ba6bc6a9e70cb8c7 Mon Sep 17 00:00:00 2001 From: darkgallium Date: Sat, 4 Jul 2020 16:59:41 +0200 Subject: corrections after review --- src/fw.rs | 67 +++++++++++++++++++++++++++++++-------------------------- src/fw_actor.rs | 8 +++---- 2 files changed, 40 insertions(+), 35 deletions(-) diff --git a/src/fw.rs b/src/fw.rs index 8ee3e6b..bc4d119 100644 --- a/src/fw.rs +++ b/src/fw.rs @@ -2,61 +2,58 @@ use iptables; use regex::Regex; use std::collections::HashSet; use crate::messages; +use anyhow::{Result,Context}; +use log::*; -#[derive(Debug)] -pub struct FirewallError(String); +pub fn setup(ipt: &iptables::IPTables) -> Result<()> { -impl From for FirewallError { - fn from(error: iptables::error::IPTError) -> Self { - FirewallError(error.to_string()) - } -} - -pub fn setup(ipt: &iptables::IPTables) -> Result<(), FirewallError> { - - if !ipt.chain_exists("filter", "DIPLONAT")? { - ipt.new_chain("filter", "DIPLONAT")?; - } - - ipt.insert_unique("filter", "INPUT", "-j DIPLONAT", 1)?; + // ensure we start from a clean state without any rule already set + cleanup(ipt)?; + + ipt.new_chain("filter", "DIPLONAT").context("Failed to create new chain")?; + ipt.insert_unique("filter", "INPUT", "-j DIPLONAT", 1).context("Failed to insert jump rule")?; Ok(()) } -pub fn open_ports(ipt: &iptables::IPTables, ports: messages::PublicExposedPorts) -> Result<(), FirewallError> { +pub fn open_ports(ipt: &iptables::IPTables, ports: messages::PublicExposedPorts) -> Result<()> { for p in ports.tcp_ports { - ipt.append("filter", "DIPLONAT", &format!("-p tcp --dport {} -j ACCEPT", p))?; + ipt.append("filter", "DIPLONAT", &format!("-p tcp --dport {} -j ACCEPT", p)).context("Failed to insert port rule")?; } for p in ports.udp_ports { - ipt.append("filter", "DIPLONAT", &format!("-p udp --dport {} -j ACCEPT", p))?; + ipt.append("filter", "DIPLONAT", &format!("-p udp --dport {} -j ACCEPT", p)).context("Failed to insert port rule")?; } Ok(()) } -pub fn get_opened_ports(ipt: &iptables::IPTables) -> Result { +pub fn get_opened_ports(ipt: &iptables::IPTables) -> Result { let mut ports = messages::PublicExposedPorts { tcp_ports: HashSet::new(), udp_ports: HashSet::new() }; let list = ipt.list("filter", "DIPLONAT")?; - let re = Regex::new(r"\-A.*? \-p (\w+).*\-\-dport (\d+).*?\-j ACCEPT").unwrap(); + let re = Regex::new(r"\-A.*? \-p (\w+).*\-\-dport (\d+).*?\-j ACCEPT").context("Regex matching open ports encountered an unexpected rule")?; for i in list { let caps = re.captures(&i); match caps { Some(c) => { - let raw_proto = c.get(1).unwrap(); - let raw_port = c.get(2).unwrap(); + + if let (Some(raw_proto), Some(raw_port)) = (c.get(1), c.get(2)) { + + let proto = String::from(raw_proto.as_str()); + let number = String::from(raw_port.as_str()).parse::()?; - let proto = String::from(raw_proto.as_str()); - let number = String::from(raw_port.as_str()).parse::().unwrap(); + if proto == "tcp" { + ports.tcp_ports.insert(number); + } else { + ports.udp_ports.insert(number); + } - if proto == "tcp" { - ports.tcp_ports.insert(number); } else { - ports.udp_ports.insert(number); + error!("Unexpected rule found in DIPLONAT chain") } }, @@ -67,10 +64,18 @@ pub fn get_opened_ports(ipt: &iptables::IPTables) -> Result Result<(), FirewallError> { - ipt.flush_chain("filter", "DIPLONAT")?; - ipt.delete("filter", "INPUT", "-j DIPLONAT")?; - ipt.delete_chain("filter", "DIPLONAT")?; +pub fn cleanup(ipt: &iptables::IPTables) -> Result<()> { + + if ipt.chain_exists("filter", "DIPLONAT")? { + ipt.flush_chain("filter", "DIPLONAT").context("Failed to flush the DIPLONAT chain")?; + + if ipt.exists("filter", "INPUT", "-j DIPLONAT")? { + ipt.delete("filter", "INPUT", "-j DIPLONAT").context("Failed to delete jump rule")?; + } + + ipt.delete_chain("filter", "DIPLONAT").context("Failed to delete chain")?; + } + Ok(()) } diff --git a/src/fw_actor.rs b/src/fw_actor.rs index 523bdaa..b5e4c7e 100644 --- a/src/fw_actor.rs +++ b/src/fw_actor.rs @@ -23,13 +23,13 @@ pub struct FirewallActor { impl FirewallActor { pub async fn new(_refresh: Duration, rxp: &watch::Receiver) -> Result { let ctx = Self { - ipt: iptables::new(false).unwrap(), + ipt: iptables::new(false)?, rx_ports: rxp.clone(), last_ports: messages::PublicExposedPorts::new(), refresh: _refresh, }; - fw::setup(&ctx.ipt).expect("iptables setup failed"); + fw::setup(&ctx.ipt)?; return Ok(ctx); } @@ -56,7 +56,7 @@ impl FirewallActor { } pub async fn do_fw_update(&self) -> Result<()> { - let curr_opened_ports = fw::get_opened_ports(&self.ipt).unwrap(); + let curr_opened_ports = fw::get_opened_ports(&self.ipt)?; let diff_tcp = self.last_ports.tcp_ports.difference(&curr_opened_ports.tcp_ports).copied().collect::>(); let diff_udp = self.last_ports.udp_ports.difference(&curr_opened_ports.udp_ports).copied().collect::>(); @@ -66,7 +66,7 @@ impl FirewallActor { udp_ports: diff_udp }; - fw::open_ports(&self.ipt, ports_to_open).unwrap(); + fw::open_ports(&self.ipt, ports_to_open)?; return Ok(()); } -- cgit v1.2.3