1 use std::sync::{Arc, Mutex};
2 use std::sync::atomic::{AtomicBool, Ordering};
4 use std::collections::HashMap;
5 use std::net::{IpAddr, Ipv4Addr, Ipv6Addr, SocketAddr};
6 use std::time::{Duration, Instant};
8 use bgp_rs::{AFI, SAFI, AddPathDirection, Open, OpenCapability, OpenParameter, NLRIEncoding, PathAttribute};
9 use bgp_rs::Capabilities;
14 use tokio::prelude::*;
16 use tokio::codec::Framed;
17 use tokio::net::TcpStream;
18 use tokio::timer::Delay;
20 use futures::sync::mpsc;
22 use crate::printer::{Printer, Stat};
23 use crate::timeout_stream::TimeoutStream;
25 const PATH_SUFFIX_LEN: usize = 3;
27 struct Route { // 32 bytes
28 path_suffix: [u32; PATH_SUFFIX_LEN],
35 v4_table: HashMap<(Ipv4Addr, u8), HashMap<u32, Route>>,
36 v6_table: HashMap<(Ipv6Addr, u8), HashMap<u32, Route>>,
42 v4_table: HashMap::new(),
43 v6_table: HashMap::new(),
47 fn get_route_attrs(&self, ip: IpAddr) -> (u8, Vec<&Route>) {
48 macro_rules! lookup_res {
49 ($addrty: ty, $addr: expr, $table: expr, $addr_bits: expr) => { {
50 //TODO: Optimize this (probably means making the tables btrees)!
51 let mut lookup = $addr.octets();
52 for i in 0..$addr_bits {
53 let lookup_addr = <$addrty>::from(lookup);
54 if let Some(routes) = $table.get(&(lookup_addr, $addr_bits - i as u8)).map(|hm| hm.values()) {
56 return ($addr_bits - i as u8, routes.collect());
59 lookup[lookup.len() - (i/8) - 1] &= !(1u8 << (i % 8));
65 IpAddr::V4(v4a) => lookup_res!(Ipv4Addr, v4a, self.v4_table, 32),
66 IpAddr::V6(v6a) => lookup_res!(Ipv6Addr, v6a, self.v6_table, 128)
70 fn withdraw(&mut self, route: NLRIEncoding) {
72 NLRIEncoding::IP(p) => {
73 let (ip, len) = <(IpAddr, u8)>::from(&p);
75 IpAddr::V4(v4a) => self.v4_table.get_mut(&(v4a, len)).and_then(|hm| hm.remove(&0)),
76 IpAddr::V6(v6a) => self.v6_table.get_mut(&(v6a, len)).and_then(|hm| hm.remove(&0)),
79 NLRIEncoding::IP_WITH_PATH_ID((p, id)) => {
80 let (ip, len) = <(IpAddr, u8)>::from(&p);
82 IpAddr::V4(v4a) => self.v4_table.get_mut(&(v4a, len)).and_then(|hm| hm.remove(&id)),
83 IpAddr::V6(v6a) => self.v6_table.get_mut(&(v6a, len)).and_then(|hm| hm.remove(&id)),
86 NLRIEncoding::IP_MPLS(_) => None,
90 fn announce(&mut self, prefix: NLRIEncoding, route: Route) {
92 NLRIEncoding::IP(p) => {
93 let (ip, len) = <(IpAddr, u8)>::from(&p);
95 IpAddr::V4(v4a) => self.v4_table.entry((v4a, len)).or_insert(HashMap::new()).insert(0, route),
96 IpAddr::V6(v6a) => self.v6_table.entry((v6a, len)).or_insert(HashMap::new()).insert(0, route),
99 NLRIEncoding::IP_WITH_PATH_ID((p, id)) => {
100 let (ip, len) = <(IpAddr, u8)>::from(&p);
102 IpAddr::V4(v4a) => self.v4_table.entry((v4a, len)).or_insert(HashMap::new()).insert(id, route),
103 IpAddr::V6(v6a) => self.v6_table.entry((v6a, len)).or_insert(HashMap::new()).insert(id, route),
106 NLRIEncoding::IP_MPLS(_) => None,
111 struct BytesCoder<'a>(&'a mut bytes::BytesMut);
112 impl<'a> std::io::Write for BytesCoder<'a> {
113 fn write(&mut self, b: &[u8]) -> Result<usize, std::io::Error> {
114 self.0.extend_from_slice(&b);
117 fn flush(&mut self) -> Result<(), std::io::Error> {
121 struct BytesDecoder<'a> {
122 buf: &'a mut bytes::BytesMut,
125 impl<'a> std::io::Read for BytesDecoder<'a> {
126 fn read(&mut self, b: &mut [u8]) -> Result<usize, std::io::Error> {
127 let copy_len = cmp::min(b.len(), self.buf.len() - self.pos);
128 b[..copy_len].copy_from_slice(&self.buf[self.pos..self.pos + copy_len]);
129 self.pos += copy_len;
134 struct MsgCoder<'a>(&'a Printer);
135 impl<'a> codec::Decoder for MsgCoder<'a> {
137 type Error = std::io::Error;
139 fn decode(&mut self, bytes: &mut bytes::BytesMut) -> Result<Option<Message>, std::io::Error> {
140 let mut decoder = BytesDecoder {
145 stream: &mut decoder,
146 capabilities: Capabilities {
147 FOUR_OCTET_ASN_SUPPORT: true,
148 EXTENDED_PATH_NLRI_SUPPORT: true,
151 Ok((_header, msg)) => {
152 decoder.buf.advance(decoder.pos);
155 Err(e) => match e.kind() {
156 std::io::ErrorKind::UnexpectedEof => Ok(None),
162 impl<'a> codec::Encoder for MsgCoder<'a> {
164 type Error = std::io::Error;
166 fn encode(&mut self, msg: Message, res: &mut bytes::BytesMut) -> Result<(), std::io::Error> {
167 msg.write(&mut BytesCoder(res))?;
172 pub struct BGPClient {
173 routes: Mutex<RoutingTable>,
174 shutdown: AtomicBool,
177 pub fn get_asn(&self, addr: IpAddr) -> u32 {
178 let lock = self.routes.lock().unwrap();
179 let mut path_vecs = lock.get_route_attrs(addr).1;
180 if path_vecs.is_empty() { return 0; }
182 path_vecs.sort_unstable_by(|path_a, path_b| {
183 path_a.pref.cmp(&path_b.pref)
184 .then(path_b.path_len.cmp(&path_a.path_len))
185 .then(path_b.med.cmp(&path_a.med))
188 let primary_route = path_vecs.pop().unwrap();
189 'asn_candidates: for asn in primary_route.path_suffix.iter().rev() {
190 if *asn == 0 { continue 'asn_candidates; }
191 for secondary_route in path_vecs.iter() {
192 if !secondary_route.path_suffix.contains(asn) {
193 continue 'asn_candidates;
199 for asn in primary_route.path_suffix.iter().rev() {
207 pub fn get_path(&self, addr: IpAddr) -> (u8, [u32; PATH_SUFFIX_LEN]) {
208 let lock = self.routes.lock().unwrap();
209 let (prefixlen, mut path_vecs) = lock.get_route_attrs(addr);
210 if path_vecs.is_empty() { return (0, [0; PATH_SUFFIX_LEN]); }
212 path_vecs.sort_unstable_by(|path_a, path_b| {
213 path_a.pref.cmp(&path_b.pref)
214 .then(path_b.path_len.cmp(&path_a.path_len))
215 .then(path_b.med.cmp(&path_a.med))
218 let primary_route = path_vecs.pop().unwrap();
219 (prefixlen, primary_route.path_suffix)
222 pub fn disconnect(&self) {
223 self.shutdown.store(true, Ordering::Relaxed);
226 fn map_attrs(mut attrs: Vec<PathAttribute>) -> Option<Route> {
227 let mut as4_path = None;
228 let mut as_path = None;
231 for attr in attrs.drain(..) {
233 PathAttribute::AS4_PATH(path) => as4_path = Some(path),
234 PathAttribute::AS_PATH(path) => as_path = Some(path),
235 PathAttribute::LOCAL_PREF(p) => pref = p,
236 PathAttribute::MULTI_EXIT_DISC(m) => med = m,
240 if let Some(mut aspath) = as4_path.or(as_path) {
241 let mut pathvec = Vec::new();
242 for seg in aspath.segments.drain(..) {
244 Segment::AS_SEQUENCE(mut asn) => pathvec.append(&mut asn),
245 Segment::AS_SET(_) => {}, // Ignore sets for now, they're not that common anyway
248 let path_len = pathvec.len() as u32;
249 pathvec.dedup_by(|a, b| (*a).eq(b)); // Drop prepends, cause we don't care in this case
251 let mut path_suffix = [0; PATH_SUFFIX_LEN];
252 for (idx, asn) in pathvec.iter().rev().enumerate() {
253 path_suffix[PATH_SUFFIX_LEN - idx - 1] = *asn;
254 if idx == PATH_SUFFIX_LEN - 1 { break; }
266 fn connect_given_client(addr: SocketAddr, timeout: Duration, printer: &'static Printer, client: Arc<BGPClient>) {
267 tokio::spawn(Delay::new(Instant::now() + timeout / 4).then(move |_| {
268 let connect_timeout = Delay::new(Instant::now() + timeout.clone()).then(|_| {
269 future::err(std::io::Error::new(std::io::ErrorKind::TimedOut, "timeout reached"))
271 let client_reconn = Arc::clone(&client);
272 TcpStream::connect(&addr).select(connect_timeout)
274 Delay::new(Instant::now() + timeout / 2).then(|_| {
277 }).and_then(move |stream| {
278 let (write, read) = Framed::new(stream.0, MsgCoder(printer)).split();
279 let (mut sender, receiver) = mpsc::channel(10); // We never really should send more than 10 messages unless they're dumb
280 tokio::spawn(write.sink_map_err(|_| { () }).send_all(receiver)
284 let _ = sender.try_send(Message::Open(Open {
287 hold_timer: timeout.as_secs() as u16,
288 identifier: 0x453b1215, // 69.59.18.21
289 parameters: vec![OpenParameter::Capabilities(vec![
290 OpenCapability::MultiProtocol((AFI::IPV4, SAFI::Unicast)),
291 OpenCapability::MultiProtocol((AFI::IPV6, SAFI::Unicast)),
292 OpenCapability::FourByteASN(397444),
293 OpenCapability::RouteRefresh,
294 OpenCapability::AddPath(vec![
295 (AFI::IPV4, SAFI::Unicast, AddPathDirection::ReceivePaths),
296 (AFI::IPV6, SAFI::Unicast, AddPathDirection::ReceivePaths)]),
299 TimeoutStream::new_persistent(read, timeout).for_each(move |bgp_msg| {
300 if client.shutdown.load(Ordering::Relaxed) {
301 return future::err(std::io::Error::new(std::io::ErrorKind::Other, "Shutting Down"));
304 Message::Open(_) => {
305 client.routes.lock().unwrap().v4_table.clear();
306 client.routes.lock().unwrap().v6_table.clear();
307 printer.add_line("Connected to BGP route provider".to_string(), false);
309 Message::KeepAlive => {
310 let _ = sender.try_send(Message::KeepAlive);
312 Message::Update(mut upd) => {
314 let mut route_table = client.routes.lock().unwrap();
315 for r in upd.withdrawn_routes {
316 route_table.withdraw(r);
318 if let Some(path) = Self::map_attrs(upd.attributes) {
319 for r in upd.announced_routes {
320 route_table.announce(r, path.clone());
323 printer.set_stat(Stat::V4RoutingTableSize(route_table.v4_table.len()));
324 printer.set_stat(Stat::V6RoutingTableSize(route_table.v6_table.len()));
329 }).or_else(move |e| {
330 printer.add_line(format!("Got error from BGP stream: {:?}", e), true);
334 if !client_reconn.shutdown.load(Ordering::Relaxed) {
335 BGPClient::connect_given_client(addr, timeout, printer, client_reconn);
343 pub fn new(addr: SocketAddr, timeout: Duration, printer: &'static Printer) -> Arc<BGPClient> {
344 let client = Arc::new(BGPClient {
345 routes: Mutex::new(RoutingTable::new()),
346 shutdown: AtomicBool::new(false),
348 BGPClient::connect_given_client(addr, timeout, printer, Arc::clone(&client));