use netlink_packet_core::NetlinkPayload;
use netlink_packet_route::{
RouteNetlinkMessage,
address::{AddressAttribute, AddressFlags, AddressMessage},
link::{LinkAttribute, LinkMessage},
};
use netlink_sys::{Socket, protocols::NETLINK_ROUTE};
use std::net::{IpAddr, Ipv4Addr, Ipv6Addr};
use std::{collections::HashMap, io};
#[cfg(feature = "gateway")]
use netlink_packet_route::AddressFamily;
#[cfg(feature = "gateway")]
use netlink_packet_route::neighbour::{NeighbourAddress, NeighbourAttribute, NeighbourMessage};
#[cfg(feature = "gateway")]
use netlink_packet_route::route::{RouteAddress, RouteAttribute, RouteMessage};
const SEQ_BASE: u32 = 0x6E_64_65_76;
fn open_route_socket() -> io::Result<Socket> {
let mut sock = Socket::new(NETLINK_ROUTE)
.map_err(|e| io::Error::new(io::ErrorKind::Other, format!("netlink open: {e}")))?;
sock.bind_auto()
.map_err(|e| io::Error::new(io::ErrorKind::Other, format!("bind_auto: {e}")))?;
super::netlink_io::set_non_blocking(&sock)?;
Ok(sock)
}
pub fn dump_links() -> io::Result<Vec<LinkMessage>> {
let mut sock = open_route_socket()?;
let seq = SEQ_BASE ^ 0x01;
super::netlink_io::send_dump(
&mut sock,
RouteNetlinkMessage::GetLink(LinkMessage::default()),
seq,
)?;
let msgs = super::netlink_io::recv_multi(&mut sock, seq)?;
let mut out = Vec::new();
for m in msgs {
if let NetlinkPayload::InnerMessage(RouteNetlinkMessage::NewLink(link)) = m.payload {
out.push(link);
}
}
Ok(out)
}
pub fn dump_addrs() -> io::Result<Vec<AddressMessage>> {
let mut sock = open_route_socket()?;
let seq = SEQ_BASE ^ 0x02;
super::netlink_io::send_dump(
&mut sock,
RouteNetlinkMessage::GetAddress(AddressMessage::default()),
seq,
)?;
let msgs = super::netlink_io::recv_multi(&mut sock, seq)?;
let mut out = Vec::new();
for m in msgs {
if let NetlinkPayload::InnerMessage(RouteNetlinkMessage::NewAddress(addr)) = m.payload {
out.push(addr);
}
}
Ok(out)
}
#[cfg(feature = "gateway")]
pub fn dump_routes() -> io::Result<Vec<RouteMessage>> {
let mut sock = open_route_socket()?;
let seq = SEQ_BASE ^ 0x03;
super::netlink_io::send_dump(
&mut sock,
RouteNetlinkMessage::GetRoute(RouteMessage::default()),
seq,
)?;
let msgs = super::netlink_io::recv_multi(&mut sock, seq)?;
let mut out = Vec::new();
for m in msgs {
if let NetlinkPayload::InnerMessage(RouteNetlinkMessage::NewRoute(rt)) = m.payload {
out.push(rt);
}
}
Ok(out)
}
#[cfg(feature = "gateway")]
pub fn dump_neigh() -> io::Result<Vec<NeighbourMessage>> {
let mut sock = open_route_socket()?;
let seq = SEQ_BASE ^ 0x04;
super::netlink_io::send_dump(
&mut sock,
RouteNetlinkMessage::GetNeighbour(NeighbourMessage::default()),
seq,
)?;
let msgs = super::netlink_io::recv_multi(&mut sock, seq)?;
let mut out = Vec::new();
for m in msgs {
if let NetlinkPayload::InnerMessage(RouteNetlinkMessage::NewNeighbour(n)) = m.payload {
out.push(n);
}
}
Ok(out)
}
fn mac_from_link(link: &LinkMessage) -> Option<[u8; 6]> {
for nla in &link.attributes {
if let LinkAttribute::Address(bytes) = nla {
if bytes.len() == 6 {
return Some([bytes[0], bytes[1], bytes[2], bytes[3], bytes[4], bytes[5]]);
}
}
}
None
}
fn name_from_link(link: &LinkMessage) -> Option<String> {
for nla in &link.attributes {
if let LinkAttribute::IfName(n) = nla {
return Some(n.clone());
}
}
None
}
fn ip_from_addr(addr: &AddressMessage) -> Option<(IpAddr, u8, u32)> {
let pfx = addr.header.prefix_len;
let mut ip_out = None;
let mut flags: Option<AddressFlags> = None;
for nla in &addr.attributes {
match nla {
AddressAttribute::Local(ip) | AddressAttribute::Address(ip) => {
ip_out = Some(*ip);
}
AddressAttribute::Flags(f) => {
flags = Some(*f);
}
_ => {}
}
}
let addr_flags = flags
.map(|f| f.bits())
.unwrap_or(addr.header.flags.bits() as u32);
ip_out.map(|ip| (ip, pfx, addr_flags))
}
#[cfg(feature = "gateway")]
fn route_addr_to_ip(a: &RouteAddress) -> Option<IpAddr> {
match a {
RouteAddress::Inet(v4) => Some(IpAddr::V4(*v4)),
RouteAddress::Inet6(v6) => Some(IpAddr::V6(*v6)),
_ => None,
}
}
#[cfg(feature = "gateway")]
fn route_extract(rt: &RouteMessage) -> (Option<IpAddr>, Option<u8>, Option<IpAddr>, Option<u32>) {
let mut dst: Option<IpAddr> = None;
let pfx: Option<u8> = Some(rt.header.destination_prefix_length);
let mut gw: Option<IpAddr> = None;
let mut oif: Option<u32> = None;
for nla in &rt.attributes {
match nla {
RouteAttribute::Destination(a) => dst = route_addr_to_ip(a),
RouteAttribute::Gateway(a) => gw = route_addr_to_ip(a),
RouteAttribute::Oif(i) => oif = Some(*i),
_ => {}
}
}
if dst.is_none() && pfx == Some(0) {
dst = match rt.header.address_family {
AddressFamily::Inet => Some(IpAddr::V4(Ipv4Addr::UNSPECIFIED)),
AddressFamily::Inet6 => Some(IpAddr::V6(Ipv6Addr::UNSPECIFIED)),
_ => None,
};
}
(dst, pfx, gw, oif)
}
#[cfg(feature = "gateway")]
fn neigh_addr_to_ip(a: &NeighbourAddress) -> Option<IpAddr> {
match a {
NeighbourAddress::Inet(v4) => Some(IpAddr::V4(*v4)),
NeighbourAddress::Inet6(v6) => Some(IpAddr::V6(*v6)),
#[allow(unreachable_patterns)]
_ => None,
}
}
#[cfg(feature = "gateway")]
fn neigh_extract(n: &NeighbourMessage) -> (Option<IpAddr>, Option<[u8; 6]>, Option<u32>) {
let mut ip = None;
let mut mac = None;
let mut oif = Some(n.header.ifindex as u32);
for nla in &n.attributes {
match nla {
NeighbourAttribute::Destination(a) => {
ip = neigh_addr_to_ip(a);
}
NeighbourAttribute::LinkLayerAddress(v) => {
if v.len() == 6 {
mac = Some([v[0], v[1], v[2], v[3], v[4], v[5]]);
}
}
NeighbourAttribute::IfIndex(i) => oif = Some(*i as u32),
_ => {}
}
}
(ip, mac, oif)
}
fn mtu_from_link(link: &LinkMessage) -> Option<u32> {
for nla in &link.attributes {
if let LinkAttribute::Mtu(m) = nla {
return Some(*m);
}
}
None
}
#[derive(Debug, Clone)]
pub struct IfRow {
pub index: u32,
pub name: String,
pub mac: Option<[u8; 6]>,
pub ipv4: Vec<(Ipv4Addr, u8)>,
pub ipv6: Vec<(Ipv6Addr, u8)>,
pub ipv6_addr_flags: Vec<u32>,
pub flags: u32,
pub mtu: Option<u32>,
}
pub fn collect_interfaces() -> io::Result<Vec<IfRow>> {
let links = dump_links()?;
let addrs = dump_addrs()?;
let mut base: HashMap<u32, IfRow> = HashMap::new();
for l in links {
let idx = l.header.index as u32;
let name = name_from_link(&l).unwrap_or_else(|| idx.to_string());
let mac = mac_from_link(&l);
let flags = l.header.flags.bits();
let mtu_nl = mtu_from_link(&l);
base.insert(
idx,
IfRow {
index: idx,
name,
mac,
ipv4: vec![],
ipv6: vec![],
ipv6_addr_flags: vec![],
flags,
mtu: mtu_nl,
},
);
}
for a in addrs {
let idx = a.header.index as u32;
if let Some((ip, pfx, addr_flags)) = ip_from_addr(&a) {
if let Some(row) = base.get_mut(&idx) {
match ip {
IpAddr::V4(v4) => row.ipv4.push((v4, pfx)),
IpAddr::V6(v6) => {
row.ipv6.push((v6, pfx));
row.ipv6_addr_flags.push(addr_flags);
}
}
}
}
}
Ok(base.into_values().collect())
}
#[cfg(feature = "gateway")]
#[derive(Debug, Clone)]
pub struct GwRow {
#[allow(dead_code)]
pub ifindex: u32,
pub gw_v4: Vec<Ipv4Addr>,
pub gw_v6: Vec<Ipv6Addr>,
pub mac: Option<[u8; 6]>,
}
#[cfg(feature = "gateway")]
pub fn collect_routes() -> io::Result<HashMap<u32, GwRow>> {
let routes = dump_routes()?;
let neighs = dump_neigh().unwrap_or_default();
let mut m: HashMap<u32, GwRow> = HashMap::new();
for rt in routes {
let (_dst, pfx, gw, oif) = route_extract(&rt);
if pfx != Some(0) {
continue;
}
let oif = match oif {
Some(i) => i,
None => continue,
};
if let Some(gwip) = gw {
let e = m.entry(oif).or_insert(GwRow {
ifindex: oif,
gw_v4: vec![],
gw_v6: vec![],
mac: None,
});
match gwip {
IpAddr::V4(v4) => {
if !e.gw_v4.contains(&v4) {
e.gw_v4.push(v4);
}
}
IpAddr::V6(v6) => {
if !e.gw_v6.contains(&v6) {
e.gw_v6.push(v6);
}
}
}
}
}
let mut mac_candidates = super::gateway::GatewayMacCandidates::default();
for n in neighs {
let (ip, mac, ifi) = neigh_extract(&n);
let ifi = match ifi {
Some(i) => i,
None => continue,
};
let (Some(row), Some(m6), Some(ip)) = (m.get_mut(&ifi), mac, ip) else {
continue;
};
match ip {
IpAddr::V4(v4) if row.gw_v4.contains(&v4) => {
mac_candidates.record_ipv4(ifi, m6);
}
IpAddr::V6(v6) if row.gw_v6.contains(&v6) => {
mac_candidates.record_ipv6(ifi, m6);
}
_ => {}
}
}
for (ifindex, row) in &mut m {
row.mac = mac_candidates.get(*ifindex);
}
Ok(m)
}