]> git.bitcoin.ninja Git - dnsseed-rust/commitdiff
Filter DNS results by common ASN
authorMatt Corallo <git@bluematt.me>
Fri, 23 Aug 2019 00:19:24 +0000 (20:19 -0400)
committerMatt Corallo <git@bluematt.me>
Fri, 23 Aug 2019 00:19:24 +0000 (20:19 -0400)
Cargo.toml
src/bgp_client.rs [new file with mode: 0644]
src/datastore.rs
src/main.rs

index 4c8459f55b0c13ea58ff5823c4701eea1bc5f4e9..3f8225acaef370db10be26fef6a0d405ce38a739 100644 (file)
@@ -7,6 +7,7 @@ edition = "2018"
 [dependencies]
 bitcoin = "0.19"
 bitcoin_hashes = "0.7"
+bgp-rs = { git = "https://github.com/TheBlueMatt/bgp-rs", rev = "330837f97b7e8e5ea3db66a4b3512863e54da8b0" }
 tokio = "0.1"
 bytes = "0.4"
 futures = "0.1"
diff --git a/src/bgp_client.rs b/src/bgp_client.rs
new file mode 100644 (file)
index 0000000..f9ab0ae
--- /dev/null
@@ -0,0 +1,293 @@
+use std::sync::{Arc, Mutex};
+use std::sync::atomic::{AtomicBool, Ordering};
+use std::cmp;
+use std::ops::Bound::Included;
+use std::collections::BTreeMap;
+use std::net::{IpAddr, Ipv4Addr, Ipv6Addr, SocketAddr};
+use std::time::{Duration, Instant};
+
+use bgp_rs::{AFI, SAFI, AddPathDirection, Open, OpenCapability, OpenParameter, NLRIEncoding, PathAttribute};
+use bgp_rs::Capabilities;
+use bgp_rs::{ASPath, Segment};
+use bgp_rs::Message;
+use bgp_rs::Reader;
+
+use tokio::prelude::*;
+use tokio::codec;
+use tokio::codec::Framed;
+use tokio::net::TcpStream;
+use tokio::timer::Delay;
+
+use futures::sync::mpsc;
+
+use crate::printer::Printer;
+
+pub struct RoutingTable {
+       v4_table: BTreeMap<(Ipv4Addr, u8, u32), Arc<Vec<PathAttribute>>>,
+       v6_table: BTreeMap<(Ipv6Addr, u8, u32), Arc<Vec<PathAttribute>>>,
+}
+
+impl RoutingTable {
+       fn new() -> Self {
+               Self {
+                       v4_table: BTreeMap::new(),
+                       v6_table: BTreeMap::new(),
+               }
+       }
+
+       fn get_route_attrs(&self, ip: IpAddr) -> Vec<Arc<Vec<PathAttribute>>> {
+               macro_rules! lookup_res {
+                       ($addrty: ty, $addr: expr, $table: expr, $addr_bits: expr) => { {
+                               let mut res = Vec::new();
+                               //TODO: Optimize this!
+                               for i in (0..($addr_bits + 1)).rev() {
+                                       let mut lookup = $addr.octets();
+                                       for b in 0..(i / 8) {
+                                               lookup[lookup.len() - b] = 0;
+                                       }
+                                       lookup[lookup.len() - (i/8)] &= !(((1u16 << (i % 8)) - 1) as u8);
+                                       let lookup_addr = <$addrty>::from(lookup);
+                                       for attrs in $table.range((Included((lookup_addr, $addr_bits, 0)), Included((lookup_addr, $addr_bits, std::u32::MAX)))) {
+                                               res.push(Arc::clone(&attrs.1));
+                                       }
+                                       if !res.is_empty() { break; }
+                               }
+                               res
+                       } }
+               }
+               match ip {
+                       IpAddr::V4(v4a) => lookup_res!(Ipv4Addr, v4a, self.v4_table, 32),
+                       IpAddr::V6(v6a) => lookup_res!(Ipv6Addr, v6a, self.v6_table, 128)
+               }
+       }
+
+       fn withdraw(&mut self, route: NLRIEncoding) {
+               match route {
+                       NLRIEncoding::IP(p) => {
+                               let (ip, len) = <(IpAddr, u8)>::from(&p);
+                               match ip {
+                                       IpAddr::V4(v4a) => self.v4_table.remove(&(v4a, len, 0)),
+                                       IpAddr::V6(v6a) => self.v6_table.remove(&(v6a, len, 0)),
+                               }
+                       },
+                       NLRIEncoding::IP_WITH_PATH_ID((p, id)) => {
+                               let (ip, len) = <(IpAddr, u8)>::from(&p);
+                               match ip {
+                                       IpAddr::V4(v4a) => self.v4_table.remove(&(v4a, len, id)),
+                                       IpAddr::V6(v6a) => self.v6_table.remove(&(v6a, len, id)),
+                               }
+                       },
+                       NLRIEncoding::IP_MPLS(_) => None,
+               };
+       }
+
+       fn announce(&mut self, route: NLRIEncoding, attrs: Arc<Vec<PathAttribute>>) {
+               match route {
+                       NLRIEncoding::IP(p) => {
+                               let (ip, len) = <(IpAddr, u8)>::from(&p);
+                               match ip {
+                                       IpAddr::V4(v4a) => self.v4_table.insert((v4a, len, 0), attrs),
+                                       IpAddr::V6(v6a) => self.v6_table.insert((v6a, len, 0), attrs),
+                               }
+                       },
+                       NLRIEncoding::IP_WITH_PATH_ID((p, id)) => {
+                               let (ip, len) = <(IpAddr, u8)>::from(&p);
+                               match ip {
+                                       IpAddr::V4(v4a) => self.v4_table.insert((v4a, len, id), attrs),
+                                       IpAddr::V6(v6a) => self.v6_table.insert((v6a, len, id), attrs),
+                               }
+                       },
+                       NLRIEncoding::IP_MPLS(_) => None,
+               };
+       }
+}
+
+struct BytesCoder<'a>(&'a mut bytes::BytesMut);
+impl<'a> std::io::Write for BytesCoder<'a> {
+       fn write(&mut self, b: &[u8]) -> Result<usize, std::io::Error> {
+               self.0.extend_from_slice(&b);
+               Ok(b.len())
+       }
+       fn flush(&mut self) -> Result<(), std::io::Error> {
+               Ok(())
+       }
+}
+struct BytesDecoder<'a> {
+       buf: &'a mut bytes::BytesMut,
+       pos: usize,
+}
+impl<'a> std::io::Read for BytesDecoder<'a> {
+       fn read(&mut self, b: &mut [u8]) -> Result<usize, std::io::Error> {
+               let copy_len = cmp::min(b.len(), self.buf.len() - self.pos);
+               b[..copy_len].copy_from_slice(&self.buf[self.pos..self.pos + copy_len]);
+               self.pos += copy_len;
+               Ok(copy_len)
+       }
+}
+
+struct MsgCoder<'a>(&'a Printer);
+impl<'a> codec::Decoder for MsgCoder<'a> {
+       type Item = Message;
+       type Error = std::io::Error;
+
+       fn decode(&mut self, bytes: &mut bytes::BytesMut) -> Result<Option<Message>, std::io::Error> {
+               let mut decoder = BytesDecoder {
+                       buf: bytes,
+                       pos: 0
+               };
+               match (Reader {
+                       stream: &mut decoder,
+                       capabilities: Capabilities {
+                               FOUR_OCTET_ASN_SUPPORT: true,
+                               EXTENDED_PATH_NLRI_SUPPORT: true,
+                       }
+               }).read() {
+                       Ok((_header, msg)) => {
+                               decoder.buf.advance(decoder.pos);
+                               Ok(Some(msg))
+                       },
+                       Err(e) => match e.kind() {
+                               std::io::ErrorKind::UnexpectedEof => Ok(None),
+                               _ => Err(e),
+                       },
+               }
+       }
+}
+impl<'a> codec::Encoder for MsgCoder<'a> {
+       type Item = Message;
+       type Error = std::io::Error;
+
+       fn encode(&mut self, msg: Message, res: &mut bytes::BytesMut) -> Result<(), std::io::Error> {
+               msg.write(&mut BytesCoder(res))?;
+               Ok(())
+       }
+}
+
+pub struct BGPClient {
+       routes: Mutex<RoutingTable>,
+       shutdown: AtomicBool,
+}
+impl BGPClient {
+       pub fn get_asn(&self, addr: IpAddr) -> u32 {
+               let attr_set = self.routes.lock().unwrap().get_route_attrs(addr);
+               let mut paths: Vec<(ASPath, u32, u32)> = Vec::new();
+               for attrs in attr_set.iter() {
+                       let mut as4_path = None;
+                       let mut as_path = None;
+                       let mut pref = 100;
+                       let mut med = 0;
+                       for attr in attrs.iter() {
+                               match attr {
+                                       PathAttribute::AS4_PATH(path) => as4_path = Some(path),
+                                       PathAttribute::AS_PATH(path) => as_path = Some(path),
+                                       PathAttribute::LOCAL_PREF(p) => pref = *p,
+                                       PathAttribute::MULTI_EXIT_DISC(m) => med = *m,
+                                       _ => {},
+                               }
+                       }
+                       if let Some(path) = as4_path.or(as_path) {
+                               paths.push((path.clone(), pref, med));
+                       }
+               }
+               if paths.is_empty() { return 0; }
+
+               let mut path_vecs: Vec<_> = paths.iter_mut().map(|(p, pref, med)| {
+                       let mut path = Vec::new();
+                       for seg in p.segments.drain(..) {
+                               match seg {
+                                       Segment::AS_SEQUENCE(mut asn) => path.append(&mut asn),
+                                       Segment::AS_SET(_) => {}, // Ignore sets for now, they're not that common anyway
+                               }
+                       }
+                       (path, pref, med)
+               }).collect();
+               path_vecs.sort_unstable_by(|(path_a, pref_a, med_a), (path_b, pref_b, med_b)| {
+                       pref_a.cmp(pref_b).then(path_b.len().cmp(&path_a.len())).then(med_b.cmp(med_a))
+               });
+               // TODO: Find last common ASN among all paths
+               *path_vecs[0].0.last().unwrap_or(&0)
+       }
+
+       pub fn disconnect(&self) {
+               self.shutdown.store(true, Ordering::Relaxed);
+       }
+
+       fn connect_given_client(addr: SocketAddr, timeout: Duration, printer: &'static Printer, client: Arc<BGPClient>) {
+               let connect_timeout = Delay::new(Instant::now() + timeout.clone()).then(|_| {
+                       future::err(std::io::Error::new(std::io::ErrorKind::TimedOut, "timeout reached"))
+               });
+               let client_reconn = Arc::clone(&client);
+               tokio::spawn(TcpStream::connect(&addr).select(connect_timeout)
+                       .or_else(move |_| {
+                               Delay::new(Instant::now() + timeout / 10).then(|_| {
+                                       future::err(())
+                               })
+                       }).and_then(move |stream| {
+                               let (write, read) = Framed::new(stream.0, MsgCoder(printer)).split();
+                               let (mut sender, receiver) = mpsc::channel(10); // We never really should send more than 10 messages unless they're dumb
+                               tokio::spawn(write.sink_map_err(|_| { () }).send_all(receiver)
+                                       .then(|_| {
+                                               future::err(())
+                                       }));
+                               let _ = sender.try_send(Message::Open(Open {
+                                       version: 4,
+                                       peer_asn: 23456,
+                                       hold_timer: 120,
+                                       identifier: 0x453b1215, // 69.59.18.21
+                                       parameters: vec![OpenParameter::Capabilities(vec![
+                                               OpenCapability::MultiProtocol((AFI::IPV4, SAFI::Unicast)),
+                                               OpenCapability::MultiProtocol((AFI::IPV6, SAFI::Unicast)),
+                                               OpenCapability::FourByteASN(397444),
+                                               OpenCapability::RouteRefresh,
+                                               OpenCapability::AddPath(vec![
+                                                       (AFI::IPV4, SAFI::Unicast, AddPathDirection::ReceivePaths),
+                                                       (AFI::IPV6, SAFI::Unicast, AddPathDirection::ReceivePaths)]),
+                                       ])]
+                               }));
+                               read.for_each(move |bgp_msg| {
+                                       if client.shutdown.load(Ordering::Relaxed) {
+                                               return future::err(std::io::Error::new(std::io::ErrorKind::Other, "Shutting Down"));
+                                       }
+                                       match bgp_msg {
+                                               Message::Open(_) => {
+                                                       printer.add_line("Connected to BGP route provider".to_string(), true);
+                                               },
+                                               Message::KeepAlive => {
+                                                       let _ = sender.try_send(Message::KeepAlive);
+                                               },
+                                               Message::Update(mut upd) => {
+                                                       upd.normalize();
+                                                       let mut route_table = client.routes.lock().unwrap();
+                                                       for r in upd.withdrawn_routes {
+                                                               route_table.withdraw(r);
+                                                       }
+                                                       let attrs = Arc::new(upd.attributes);
+                                                       for r in upd.announced_routes {
+                                                               route_table.announce(r, Arc::clone(&attrs));
+                                                       }
+                                               },
+                                               _ => {}
+                                       }
+                                       future::ok(())
+                               }).or_else(move |e| {
+                                       printer.add_line(format!("Got error from BGP stream: {:?}", e), true);
+                                       future::ok(())
+                               })
+                       }).then(move |_| {
+                               if !client_reconn.shutdown.load(Ordering::Relaxed) {
+                                       BGPClient::connect_given_client(addr, timeout, printer, client_reconn);
+                               }
+                               future::ok(())
+                       })
+               );
+       }
+
+       pub fn new(addr: SocketAddr, timeout: Duration, printer: &'static Printer) -> Arc<BGPClient> {
+               let client = Arc::new(BGPClient {
+                       routes: Mutex::new(RoutingTable::new()),
+                       shutdown: AtomicBool::new(false),
+               });
+               BGPClient::connect_given_client(addr, timeout, printer, Arc::clone(&client));
+               client
+       }
+}
index 30d2c8e8b21431cf917c0ec6d1436c7016f3a07c..c8ef0e0aed812f52599ac6d1ca47dcde0692e48b 100644 (file)
@@ -16,6 +16,8 @@ use tokio::io::write_all;
 
 use regex::Regex;
 
+use crate::bgp_client::BGPClient;
+
 #[derive(Clone, Copy, Hash, PartialEq, Eq)]
 pub enum AddressState {
        Untested,
@@ -437,7 +439,7 @@ impl Store {
                settings_future.join(nodes_future).then(|_| { future::ok(()) })
        }
 
-       pub fn write_dns(&'static self) -> impl Future<Item=(), Error=()> {
+       pub fn write_dns(&'static self, bgp_client: Arc<BGPClient>) -> impl Future<Item=(), Error=()> {
                let dns_file = self.store.clone() + "/nodes.dump";
                File::create(dns_file.clone() + ".tmp").and_then(move |f| {
                        let mut dns_buff = String::new();
@@ -496,10 +498,12 @@ impl Store {
                                                                .filter(|e| e.is_ipv6() && e.port() == 8333).map(|e| e.ip()).collect();
                                                }
                                        }
-                                       for a in v4_set.iter().choose_multiple(&mut rng, 21) {
+                                       let mut asn_set = HashSet::with_capacity(cmp::max(v4_set.len(), v6_set.len()));
+                                       for a in v4_set.iter().filter(|a| asn_set.insert(bgp_client.get_asn(**a))).choose_multiple(&mut rng, 21) {
                                                dns_buff += &format!("x{:x}.dnsseed\tIN\tA\t{}\n", i, a);
                                        }
-                                       for a in v6_set.iter().choose_multiple(&mut rng, 12) {
+                                       asn_set.clear();
+                                       for a in v6_set.iter().filter(|a| asn_set.insert(bgp_client.get_asn(**a))).choose_multiple(&mut rng, 12) {
                                                dns_buff += &format!("x{:x}.dnsseed\tIN\tAAAA\t{}\n", i, a);
                                        }
                                }
index f72ba343a1972cbc1ddb03e06e2584ee7e25ded1..ba206d60de29e42484cb84c0e0ddf5be6d6346dd 100644 (file)
@@ -1,6 +1,7 @@
 mod printer;
 mod reader;
 mod peer;
+mod bgp_client;
 mod timeout_stream;
 mod datastore;
 
@@ -25,6 +26,7 @@ use peer::Peer;
 use datastore::{AddressState, Store, U64Setting, RegexSetting};
 use timeout_stream::TimeoutStream;
 use rand::Rng;
+use bgp_client::BGPClient;
 
 use tokio::prelude::*;
 use tokio::timer::Delay;
@@ -245,7 +247,7 @@ pub fn scan_node(scan_time: Instant, node: SocketAddr, manual: bool) {
        }));
 }
 
-fn poll_dnsseeds() {
+fn poll_dnsseeds(bgp_client: Arc<BGPClient>) {
        tokio::spawn(future::lazy(|| {
                let printer = unsafe { PRINTER.as_ref().unwrap() };
                let store = unsafe { DATA_STORE.as_ref().unwrap() };
@@ -258,10 +260,12 @@ fn poll_dnsseeds() {
                printer.add_line(format!("Added {} new addresses from other DNS seeds", new_addrs), false);
                Delay::new(Instant::now() + Duration::from_secs(60)).then(|_| {
                        let store = unsafe { DATA_STORE.as_ref().unwrap() };
-                       let dns_future = store.write_dns();
+                       let dns_future = store.write_dns(Arc::clone(&bgp_client));
                        store.save_data().join(dns_future).then(|_| {
                                if !START_SHUTDOWN.load(Ordering::Relaxed) {
-                                       poll_dnsseeds();
+                                       poll_dnsseeds(bgp_client);
+                               } else {
+                                       bgp_client.disconnect();
                                }
                                future::ok(())
                        })
@@ -293,9 +297,10 @@ fn scan_net() {
        }));
 }
 
-fn make_trusted_conn(trusted_sockaddr: SocketAddr) {
+fn make_trusted_conn(trusted_sockaddr: SocketAddr, bgp_client: Arc<BGPClient>) {
        let printer = unsafe { PRINTER.as_ref().unwrap() };
        let trusted_peer = Peer::new(trusted_sockaddr.clone(), Duration::from_secs(600), printer);
+       let bgp_reload = Arc::clone(&bgp_client);
        tokio::spawn(trusted_peer.and_then(move |(mut trusted_write, trusted_read)| {
                printer.add_line("Connected to local peer".to_string(), false);
                let mut starting_height = 0;
@@ -378,7 +383,7 @@ fn make_trusted_conn(trusted_sockaddr: SocketAddr) {
                                                *unsafe { REQUEST_BLOCK.as_ref().unwrap() }.lock().unwrap() = Arc::new((height, hash, block));
                                                if !SCANNING.swap(true, Ordering::SeqCst) {
                                                        scan_net();
-                                                       poll_dnsseeds();
+                                                       poll_dnsseeds(Arc::clone(&bgp_client));
                                                }
                                        }
                                },
@@ -396,15 +401,15 @@ fn make_trusted_conn(trusted_sockaddr: SocketAddr) {
        }).then(move |_: Result<(), ()>| {
                if !START_SHUTDOWN.load(Ordering::Relaxed) {
                        printer.add_line("Lost connection from trusted peer".to_string(), true);
-                       make_trusted_conn(trusted_sockaddr);
+                       make_trusted_conn(trusted_sockaddr, bgp_reload);
                }
                future::ok(())
        }));
 }
 
 fn main() {
-       if env::args().len() != 3 {
-               println!("USAGE: dnsseed-rust datastore localPeerAddress");
+       if env::args().len() != 4 {
+               println!("USAGE: dnsseed-rust datastore localPeerAddress bgp_peer");
                return;
        }
 
@@ -423,15 +428,16 @@ fn main() {
                let mut args = env::args();
                args.next();
                let path = args.next().unwrap();
-               let addr = args.next().unwrap();
+               let trusted_sockaddr: SocketAddr = args.next().unwrap().parse().unwrap();
+               let bgp_sockaddr: SocketAddr = args.next().unwrap().parse().unwrap();
 
                Store::new(path).and_then(move |store| {
                        unsafe { DATA_STORE = Some(Box::new(store)) };
                        let store = unsafe { DATA_STORE.as_ref().unwrap() };
                        unsafe { PRINTER = Some(Box::new(Printer::new(store))) };
 
-                       let trusted_sockaddr: SocketAddr = addr.parse().unwrap();
-                       make_trusted_conn(trusted_sockaddr);
+                       let bgp_client = BGPClient::new(bgp_sockaddr, Duration::from_secs(600), unsafe { PRINTER.as_ref().unwrap() });
+                       make_trusted_conn(trusted_sockaddr, bgp_client);
 
                        reader::read(store, unsafe { PRINTER.as_ref().unwrap() });