restore: networking stack files from reflog (Phases 1-6)

Recovered from reflog commits 1c80937e and d0ecc067 after force-push data loss.
Includes: filter/, icmp_error.rs, slaac.rs, bond.rs, bridge.rs, gre.rs, ipip.rs,
qdisc.rs, tun.rs, vlan.rs, vxlan.rs, netfilter.rs, tun.rs, conntrack.rs, nat.rs,
rule.rs, table.rs, redbear-ufw/, dhcpv6d/, netdiag/ — 39 files total.

netstack/src/main.rs

@@ -13,11 +13,14 @@ use smoltcp::wire::EthernetAddress;
 
 mod buffer_pool;
 mod error;
+mod filter;
+mod icmp_error;
 mod link;
 mod logger;
 mod port_set;
 mod router;
 mod scheme;
+mod slaac;
 
 fn get_network_adapter() -> Result<String> {
     use std::fs;
@@ -82,6 +85,14 @@ fn run(daemon: daemon::Daemon) -> Result<()> {
     let netcfg_fd =
         Socket::nonblock().map_err(|e| anyhow!("failed to open netcfg scheme socket {:?}", e))?;
 
+    trace!("opening netfilter scheme socket");
+    let netfilter_fd =
+        Socket::nonblock().map_err(|e| anyhow!("failed to open netfilter scheme socket: {:?}", e))?;
+
+    trace!("opening tun scheme socket");
+    let tun_fd =
+        Socket::nonblock().map_err(|e| anyhow!("failed to open tun scheme socket: {:?}", e))?;
+
     let time_path = format!("/scheme/time/{}", syscall::CLOCK_MONOTONIC);
     let time_fd = Fd::open(&time_path, O_RDWR, 0).context("failed to open /scheme/time")?;
 
@@ -94,6 +105,7 @@ fn run(daemon: daemon::Daemon) -> Result<()> {
             TcpScheme,
             IcmpScheme,
             NetcfgScheme,
+            NetfilterScheme,
         }
     }
 
@@ -146,6 +158,14 @@ fn run(daemon: daemon::Daemon) -> Result<()> {
         )
         .map_err(|e| anyhow!("failed to listen to netcfg scheme events: {:?}", e))?;
 
+    event_queue
+        .subscribe(
+            netfilter_fd.inner().raw(),
+            EventSource::NetfilterScheme,
+            EventFlags::READ,
+        )
+        .map_err(|e| anyhow!("failed to listen to netfilter scheme events: {:?}", e))?;
+
     let mut smolnetd = Smolnetd::new(
         network_fd,
         hardware_addr,
@@ -155,6 +175,7 @@ fn run(daemon: daemon::Daemon) -> Result<()> {
         icmp_fd,
         time_fd,
         netcfg_fd,
+        netfilter_fd,
     )
     .context("smolnetd: failed to initialize smolnetd")?;
 
@@ -162,7 +183,7 @@ fn run(daemon: daemon::Daemon) -> Result<()> {
 
     let all = {
         use EventSource::*;
-        [Network, Time, IpScheme, UdpScheme, IcmpScheme, NetcfgScheme].map(Ok)
+        [Network, Time, IpScheme, UdpScheme, IcmpScheme, NetcfgScheme, NetfilterScheme].map(Ok)
     };
 
     for event_res in all
@@ -177,6 +198,7 @@ fn run(daemon: daemon::Daemon) -> Result<()> {
             EventSource::TcpScheme => smolnetd.on_tcp_scheme_event(),
             EventSource::IcmpScheme => smolnetd.on_icmp_scheme_event(),
             EventSource::NetcfgScheme => smolnetd.on_netcfg_scheme_event(),
+            EventSource::NetfilterScheme => smolnetd.on_netfilter_scheme_event(),
         }
         .map_err(|e| error!("Received packet error: {:?}", e));
     }