reth_network/
error.rs

1//! Possible errors when interacting with the network.
2
3use crate::session::PendingSessionHandshakeError;
4use reth_dns_discovery::resolver::ResolveError;
5use reth_ecies::ECIESErrorImpl;
6use reth_eth_wire::{
7    errors::{EthHandshakeError, EthStreamError, P2PHandshakeError, P2PStreamError},
8    DisconnectReason,
9};
10use reth_network_types::BackoffKind;
11use std::{fmt, io, io::ErrorKind, net::SocketAddr};
12
13/// Service kind.
14#[derive(Debug, PartialEq, Eq, Copy, Clone)]
15pub enum ServiceKind {
16    /// Listener service.
17    Listener(SocketAddr),
18    /// Discovery service.
19    Discovery(SocketAddr),
20}
21
22impl ServiceKind {
23    /// Returns the appropriate flags for each variant.
24    pub const fn flags(&self) -> &'static str {
25        match self {
26            Self::Listener(_) => "--port",
27            Self::Discovery(_) => "--discovery.port",
28        }
29    }
30}
31
32impl fmt::Display for ServiceKind {
33    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
34        match self {
35            Self::Listener(addr) => write!(f, "{addr} (listener service)"),
36            Self::Discovery(addr) => write!(f, "{addr} (discovery service)"),
37        }
38    }
39}
40
41/// All error variants for the network
42#[derive(Debug, thiserror::Error)]
43pub enum NetworkError {
44    /// General IO error.
45    #[error(transparent)]
46    Io(#[from] io::Error),
47    /// Error when an address is already in use.
48    #[error("address {kind} is already in use (os error 98). Choose a different port using {}", kind.flags())]
49    AddressAlreadyInUse {
50        /// Service kind.
51        kind: ServiceKind,
52        /// IO error.
53        error: io::Error,
54    },
55    /// IO error when creating the discovery service
56    #[error("failed to launch discovery service on {0}: {1}")]
57    Discovery(SocketAddr, io::Error),
58    /// An error occurred with discovery v5 node.
59    #[error("discv5 error, {0}")]
60    Discv5Error(#[from] reth_discv5::Error),
61    /// Error when setting up the DNS resolver failed
62    ///
63    /// See also [`DnsResolver`](reth_dns_discovery::DnsResolver::from_system_conf)
64    #[error("failed to configure DNS resolver: {0}")]
65    DnsResolver(#[from] ResolveError),
66}
67
68impl NetworkError {
69    /// Converts a `std::io::Error` to a more descriptive `NetworkError`.
70    pub fn from_io_error(err: io::Error, kind: ServiceKind) -> Self {
71        match err.kind() {
72            ErrorKind::AddrInUse => Self::AddressAlreadyInUse { kind, error: err },
73            _ => {
74                if let ServiceKind::Discovery(address) = kind {
75                    return Self::Discovery(address, err)
76                }
77                Self::Io(err)
78            }
79        }
80    }
81}
82
83/// Abstraction over errors that can lead to a failed session
84#[auto_impl::auto_impl(&)]
85pub(crate) trait SessionError: fmt::Debug + fmt::Display {
86    /// Returns true if the error indicates that the corresponding peer should be removed from peer
87    /// discovery, for example if it's using a different genesis hash.
88    fn merits_discovery_ban(&self) -> bool;
89
90    /// Returns true if the error indicates that we'll never be able to establish a connection to
91    /// that peer. For example, not matching capabilities or a mismatch in protocols.
92    ///
93    /// Note: This does not necessarily mean that either of the peers are in violation of the
94    /// protocol but rather that they'll never be able to connect with each other. This check is
95    /// a superset of [`Self::merits_discovery_ban`] which checks if the peer should not be part
96    /// of the gossip network.
97    fn is_fatal_protocol_error(&self) -> bool;
98
99    /// Whether we should backoff.
100    ///
101    /// Returns the severity of the backoff that should be applied, or `None`, if no backoff should
102    /// be applied.
103    ///
104    /// In case of `Some(BackoffKind)` will temporarily prevent additional
105    /// connection attempts.
106    fn should_backoff(&self) -> Option<BackoffKind>;
107}
108
109impl SessionError for EthStreamError {
110    fn merits_discovery_ban(&self) -> bool {
111        match self {
112            Self::P2PStreamError(P2PStreamError::HandshakeError(
113                P2PHandshakeError::HelloNotInHandshake |
114                P2PHandshakeError::NonHelloMessageInHandshake,
115            )) => true,
116            Self::EthHandshakeError(err) => !matches!(err, EthHandshakeError::NoResponse),
117            _ => false,
118        }
119    }
120
121    fn is_fatal_protocol_error(&self) -> bool {
122        match self {
123            Self::P2PStreamError(err) => {
124                matches!(
125                    err,
126                    P2PStreamError::HandshakeError(
127                        P2PHandshakeError::NoSharedCapabilities |
128                            P2PHandshakeError::HelloNotInHandshake |
129                            P2PHandshakeError::NonHelloMessageInHandshake |
130                            P2PHandshakeError::Disconnected(
131                                DisconnectReason::UselessPeer |
132                                    DisconnectReason::IncompatibleP2PProtocolVersion |
133                                    DisconnectReason::ProtocolBreach
134                            )
135                    ) | P2PStreamError::UnknownReservedMessageId(_) |
136                        P2PStreamError::EmptyProtocolMessage |
137                        P2PStreamError::ParseSharedCapability(_) |
138                        P2PStreamError::CapabilityNotShared |
139                        P2PStreamError::Disconnected(
140                            DisconnectReason::UselessPeer |
141                                DisconnectReason::IncompatibleP2PProtocolVersion |
142                                DisconnectReason::ProtocolBreach
143                        ) |
144                        P2PStreamError::MismatchedProtocolVersion { .. }
145                )
146            }
147            Self::EthHandshakeError(err) => !matches!(err, EthHandshakeError::NoResponse),
148            _ => false,
149        }
150    }
151
152    fn should_backoff(&self) -> Option<BackoffKind> {
153        if let Some(err) = self.as_io() {
154            return err.should_backoff()
155        }
156
157        if let Some(err) = self.as_disconnected() {
158            return match err {
159                DisconnectReason::TooManyPeers |
160                DisconnectReason::AlreadyConnected |
161                DisconnectReason::PingTimeout |
162                DisconnectReason::DisconnectRequested |
163                DisconnectReason::TcpSubsystemError => Some(BackoffKind::Low),
164
165                DisconnectReason::ProtocolBreach |
166                DisconnectReason::UselessPeer |
167                DisconnectReason::IncompatibleP2PProtocolVersion |
168                DisconnectReason::NullNodeIdentity |
169                DisconnectReason::ClientQuitting |
170                DisconnectReason::UnexpectedHandshakeIdentity |
171                DisconnectReason::ConnectedToSelf |
172                DisconnectReason::SubprotocolSpecific => {
173                    // These are considered fatal, and are handled by the
174                    // [`SessionError::is_fatal_protocol_error`]
175                    Some(BackoffKind::High)
176                }
177            }
178        }
179
180        // This only checks for a subset of error variants, the counterpart of
181        // [`SessionError::is_fatal_protocol_error`]
182        match self {
183            // timeouts
184            Self::EthHandshakeError(EthHandshakeError::NoResponse) |
185            Self::P2PStreamError(
186                P2PStreamError::HandshakeError(P2PHandshakeError::NoResponse) |
187                P2PStreamError::PingTimeout,
188            ) => Some(BackoffKind::Low),
189            // malformed messages
190            Self::P2PStreamError(
191                P2PStreamError::Rlp(_) |
192                P2PStreamError::UnknownReservedMessageId(_) |
193                P2PStreamError::UnknownDisconnectReason(_) |
194                P2PStreamError::MessageTooBig { .. } |
195                P2PStreamError::EmptyProtocolMessage |
196                P2PStreamError::PingerError(_) |
197                P2PStreamError::Snap(_),
198            ) => Some(BackoffKind::Medium),
199            _ => None,
200        }
201    }
202}
203
204impl SessionError for PendingSessionHandshakeError {
205    fn merits_discovery_ban(&self) -> bool {
206        match self {
207            Self::Eth(eth) => eth.merits_discovery_ban(),
208            Self::Ecies(err) => matches!(
209                err.inner(),
210                ECIESErrorImpl::TagCheckDecryptFailed |
211                    ECIESErrorImpl::TagCheckHeaderFailed |
212                    ECIESErrorImpl::TagCheckBodyFailed |
213                    ECIESErrorImpl::InvalidAuthData |
214                    ECIESErrorImpl::InvalidAckData |
215                    ECIESErrorImpl::InvalidHeader |
216                    ECIESErrorImpl::Secp256k1(_) |
217                    ECIESErrorImpl::InvalidHandshake { .. }
218            ),
219            Self::Timeout | Self::UnsupportedExtraCapability => false,
220        }
221    }
222
223    fn is_fatal_protocol_error(&self) -> bool {
224        match self {
225            Self::Eth(eth) => eth.is_fatal_protocol_error(),
226            Self::Ecies(err) => matches!(
227                err.inner(),
228                ECIESErrorImpl::TagCheckDecryptFailed |
229                    ECIESErrorImpl::TagCheckHeaderFailed |
230                    ECIESErrorImpl::TagCheckBodyFailed |
231                    ECIESErrorImpl::InvalidAuthData |
232                    ECIESErrorImpl::InvalidAckData |
233                    ECIESErrorImpl::InvalidHeader |
234                    ECIESErrorImpl::Secp256k1(_) |
235                    ECIESErrorImpl::InvalidHandshake { .. }
236            ),
237            Self::Timeout => false,
238            Self::UnsupportedExtraCapability => true,
239        }
240    }
241
242    fn should_backoff(&self) -> Option<BackoffKind> {
243        match self {
244            Self::Eth(eth) => eth.should_backoff(),
245            Self::Ecies(_) => Some(BackoffKind::Low),
246            Self::Timeout => Some(BackoffKind::Medium),
247            Self::UnsupportedExtraCapability => Some(BackoffKind::High),
248        }
249    }
250}
251
252impl SessionError for io::Error {
253    fn merits_discovery_ban(&self) -> bool {
254        false
255    }
256
257    fn is_fatal_protocol_error(&self) -> bool {
258        false
259    }
260
261    fn should_backoff(&self) -> Option<BackoffKind> {
262        match self.kind() {
263            // these usually happen when the remote instantly drops the connection, for example
264            // if the previous connection isn't properly cleaned up yet and the peer is temp.
265            // banned.
266            ErrorKind::ConnectionReset | ErrorKind::BrokenPipe => Some(BackoffKind::Low),
267            ErrorKind::ConnectionRefused => {
268                // peer is unreachable, e.g. port not open or down
269                Some(BackoffKind::High)
270            }
271            _ => Some(BackoffKind::Medium),
272        }
273    }
274}
275
276#[cfg(test)]
277mod tests {
278    use super::*;
279    use std::net::{Ipv4Addr, SocketAddrV4};
280
281    #[test]
282    fn test_is_fatal_disconnect() {
283        let err = PendingSessionHandshakeError::Eth(EthStreamError::P2PStreamError(
284            P2PStreamError::HandshakeError(P2PHandshakeError::Disconnected(
285                DisconnectReason::UselessPeer,
286            )),
287        ));
288
289        assert!(err.is_fatal_protocol_error());
290    }
291
292    #[test]
293    fn test_should_backoff() {
294        let err = EthStreamError::P2PStreamError(P2PStreamError::HandshakeError(
295            P2PHandshakeError::Disconnected(DisconnectReason::TooManyPeers),
296        ));
297
298        assert_eq!(err.as_disconnected(), Some(DisconnectReason::TooManyPeers));
299        assert_eq!(err.should_backoff(), Some(BackoffKind::Low));
300
301        let err = EthStreamError::P2PStreamError(P2PStreamError::HandshakeError(
302            P2PHandshakeError::NoResponse,
303        ));
304        assert_eq!(err.should_backoff(), Some(BackoffKind::Low));
305    }
306
307    #[test]
308    fn test_address_in_use_message() {
309        let addr = SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(127, 0, 0, 1), 1234));
310        let kinds = [ServiceKind::Discovery(addr), ServiceKind::Listener(addr)];
311
312        for kind in &kinds {
313            let err = NetworkError::AddressAlreadyInUse {
314                kind: *kind,
315                error: io::Error::from(ErrorKind::AddrInUse),
316            };
317
318            assert!(err.to_string().contains(kind.flags()));
319        }
320    }
321}
reth_network/error.rs

reth_network/
error.rs
