1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
// Copyright 2015-2017 Parity Technologies (UK) Ltd.
// This file is part of Parity.

// Parity is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// Parity is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with Parity.  If not, see <http://www.gnu.org/licenses/>.

use std::sync::Arc;
use std::collections::{HashMap, BTreeMap};
use std::io;
use util::Bytes;
use network::{NetworkProtocolHandler, NetworkService, NetworkContext, PeerId, ProtocolId,
	NetworkConfiguration as BasicNetworkConfiguration, NonReservedPeerMode, NetworkError,
	AllowIP as NetworkAllowIP};
use util::{U256, H256, H512};
use io::{TimerToken};
use ethcore::ethstore::ethkey::Secret;
use ethcore::client::{BlockChainClient, ChainNotify};
use ethcore::snapshot::SnapshotService;
use ethcore::header::BlockNumber;
use sync_io::NetSyncIo;
use chain::{ChainSync, SyncStatus};
use std::net::{SocketAddr, AddrParseError};
use ipc::{BinaryConvertable, BinaryConvertError, IpcConfig};
use std::str::FromStr;
use parking_lot::RwLock;
use chain::{ETH_PACKET_COUNT, SNAPSHOT_SYNC_PACKET_COUNT};
use light::client::LightChainClient;
use light::Provider;
use light::net::{self as light_net, LightProtocol, Params as LightParams, Capabilities, Handler as LightHandler, EventContext};

/// Parity sync protocol
pub const WARP_SYNC_PROTOCOL_ID: ProtocolId = *b"par";
/// Ethereum sync protocol
pub const ETH_PROTOCOL: ProtocolId = *b"eth";
/// Ethereum light protocol
pub const LES_PROTOCOL: ProtocolId = *b"les";

/// Sync configuration
#[derive(Debug, Clone, Copy)]
pub struct SyncConfig {
	/// Max blocks to download ahead
	pub max_download_ahead_blocks: usize,
	/// Enable ancient block download.
	pub download_old_blocks: bool,
	/// Network ID
	pub network_id: u64,
	/// Main "eth" subprotocol name.
	pub subprotocol_name: [u8; 3],
	/// Light "les" subprotocol name.
	pub light_subprotocol_name: [u8; 3],
	/// Fork block to check
	pub fork_block: Option<(BlockNumber, H256)>,
	/// Enable snapshot sync
	pub warp_sync: bool,
	/// Enable light client server.
	pub serve_light: bool,
}

impl Default for SyncConfig {
	fn default() -> SyncConfig {
		SyncConfig {
			max_download_ahead_blocks: 20000,
			download_old_blocks: true,
			network_id: 1,
			subprotocol_name: ETH_PROTOCOL,
			light_subprotocol_name: LES_PROTOCOL,
			fork_block: None,
			warp_sync: false,
			serve_light: false,
		}
	}
}

binary_fixed_size!(SyncConfig);
binary_fixed_size!(SyncStatus);

/// Current sync status
pub trait SyncProvider: Send + Sync {
	/// Get sync status
	fn status(&self) -> SyncStatus;

	/// Get peers information
	fn peers(&self) -> Vec<PeerInfo>;

	/// Get the enode if available.
	fn enode(&self) -> Option<String>;

	/// Returns propagation count for pending transactions.
	fn transactions_stats(&self) -> BTreeMap<H256, TransactionStats>;
}

/// Transaction stats
#[derive(Debug)]
#[cfg_attr(feature = "ipc", derive(Binary))]
pub struct TransactionStats {
	/// Block number where this TX was first seen.
	pub first_seen: u64,
	/// Peers it was propagated to.
	pub propagated_to: BTreeMap<H512, usize>,
}

/// Peer connection information
#[derive(Debug)]
#[cfg_attr(feature = "ipc", derive(Binary))]
pub struct PeerInfo {
	/// Public node id
	pub id: Option<String>,
	/// Node client ID
	pub client_version: String,
	/// Capabilities
	pub capabilities: Vec<String>,
	/// Remote endpoint address
	pub remote_address: String,
	/// Local endpoint address
	pub local_address: String,
	/// Eth protocol info.
	pub eth_info: Option<EthProtocolInfo>,
	/// Light protocol info.
	pub les_info: Option<LesProtocolInfo>,
}

/// Ethereum protocol info.
#[derive(Debug)]
#[cfg_attr(feature = "ipc", derive(Binary))]
pub struct EthProtocolInfo {
	/// Protocol version
	pub version: u32,
	/// SHA3 of peer best block hash
	pub head: H256,
	/// Peer total difficulty if known
	pub difficulty: Option<U256>,
}

/// LES protocol info.
#[derive(Debug)]
#[cfg_attr(feature = "ipc", derive(Binary))]
pub struct LesProtocolInfo {
	/// Protocol version
	pub version: u32,
	/// SHA3 of peer best block hash
	pub head: H256,
	/// Peer total difficulty if known
	pub difficulty: U256,
}

impl From<light_net::Status> for LesProtocolInfo {
	fn from(status: light_net::Status) -> Self {
		LesProtocolInfo {
			version: status.protocol_version,
			head: status.head_hash,
			difficulty: status.head_td,
		}
	}
}

/// EthSync initialization parameters.
#[cfg_attr(feature = "ipc", derive(Binary))]
pub struct Params {
	/// Configuration.
	pub config: SyncConfig,
	/// Blockchain client.
	pub chain: Arc<BlockChainClient>,
	/// Snapshot service.
	pub snapshot_service: Arc<SnapshotService>,
	/// Light data provider.
	pub provider: Arc<::light::Provider>,
	/// Network layer configuration.
	pub network_config: NetworkConfiguration,
}

/// Ethereum network protocol handler
pub struct EthSync {
	/// Network service
	network: NetworkService,
	/// Main (eth/par) protocol handler
	eth_handler: Arc<SyncProtocolHandler>,
	/// Light (les) protocol handler
	light_proto: Option<Arc<LightProtocol>>,
	/// The main subprotocol name
	subprotocol_name: [u8; 3],
	/// Light subprotocol name.
	light_subprotocol_name: [u8; 3],
}

impl EthSync {
	/// Creates and register protocol with the network service
	pub fn new(params: Params) -> Result<Arc<EthSync>, NetworkError> {
		let pruning_info = params.chain.pruning_info();
		let light_proto = match params.config.serve_light {
			false => None,
			true => Some({
				let light_params = LightParams {
					network_id: params.config.network_id,
					flow_params: Default::default(),
					capabilities: Capabilities {
						serve_headers: true,
						serve_chain_since: Some(pruning_info.earliest_chain),
						serve_state_since: Some(pruning_info.earliest_state),
						tx_relay: true,
					},
				};

				let mut light_proto = LightProtocol::new(params.provider, light_params);
				light_proto.add_handler(Arc::new(TxRelay(params.chain.clone())));

				Arc::new(light_proto)
			})
		};

		let chain_sync = ChainSync::new(params.config, &*params.chain);
		let service = NetworkService::new(params.network_config.clone().into_basic()?)?;

		let sync = Arc::new(EthSync {
			network: service,
			eth_handler: Arc::new(SyncProtocolHandler {
				sync: RwLock::new(chain_sync),
				chain: params.chain,
				snapshot_service: params.snapshot_service,
				overlay: RwLock::new(HashMap::new()),
			}),
			light_proto: light_proto,
			subprotocol_name: params.config.subprotocol_name,
			light_subprotocol_name: params.config.light_subprotocol_name,
		});

		Ok(sync)
	}
}

#[cfg_attr(feature = "ipc", ipc(client_ident="SyncClient"))]
impl SyncProvider for EthSync {
	/// Get sync status
	fn status(&self) -> SyncStatus {
		self.eth_handler.sync.write().status()
	}

	/// Get sync peers
	fn peers(&self) -> Vec<PeerInfo> {
		self.network.with_context_eval(self.subprotocol_name, |ctx| {
			let peer_ids = self.network.connected_peers();
			let eth_sync = self.eth_handler.sync.read();
			let light_proto = self.light_proto.as_ref();

			peer_ids.into_iter().filter_map(|peer_id| {
				let session_info = match ctx.session_info(peer_id) {
					None => return None,
					Some(info) => info,
				};

				Some(PeerInfo {
					id: session_info.id.map(|id| id.hex()),
					client_version: session_info.client_version,
					capabilities: session_info.peer_capabilities.into_iter().map(|c| c.to_string()).collect(),
					remote_address: session_info.remote_address,
					local_address: session_info.local_address,
					eth_info: eth_sync.peer_info(&peer_id),
					les_info: light_proto.as_ref().and_then(|lp| lp.peer_status(&peer_id)).map(Into::into),
				})
			}).collect()
		}).unwrap_or_else(Vec::new)
	}

	fn enode(&self) -> Option<String> {
		self.network.external_url()
	}

	fn transactions_stats(&self) -> BTreeMap<H256, TransactionStats> {
		let sync = self.eth_handler.sync.read();
		sync.transactions_stats()
			.iter()
			.map(|(hash, stats)| (*hash, stats.into()))
			.collect()
	}
}

struct SyncProtocolHandler {
	/// Shared blockchain client.
	chain: Arc<BlockChainClient>,
	/// Shared snapshot service.
	snapshot_service: Arc<SnapshotService>,
	/// Sync strategy
	sync: RwLock<ChainSync>,
	/// Chain overlay used to cache data such as fork block.
	overlay: RwLock<HashMap<BlockNumber, Bytes>>,
}

impl NetworkProtocolHandler for SyncProtocolHandler {
	fn initialize(&self, io: &NetworkContext) {
		if io.subprotocol_name() != WARP_SYNC_PROTOCOL_ID {
			io.register_timer(0, 1000).expect("Error registering sync timer");
		}
	}

	fn read(&self, io: &NetworkContext, peer: &PeerId, packet_id: u8, data: &[u8]) {
		ChainSync::dispatch_packet(&self.sync, &mut NetSyncIo::new(io, &*self.chain, &*self.snapshot_service, &self.overlay), *peer, packet_id, data);
	}

	fn connected(&self, io: &NetworkContext, peer: &PeerId) {
		// If warp protocol is supported only allow warp handshake
		let warp_protocol = io.protocol_version(WARP_SYNC_PROTOCOL_ID, *peer).unwrap_or(0) != 0;
		let warp_context = io.subprotocol_name() == WARP_SYNC_PROTOCOL_ID;
		if warp_protocol == warp_context {
			self.sync.write().on_peer_connected(&mut NetSyncIo::new(io, &*self.chain, &*self.snapshot_service, &self.overlay), *peer);
		}
	}

	fn disconnected(&self, io: &NetworkContext, peer: &PeerId) {
		if io.subprotocol_name() != WARP_SYNC_PROTOCOL_ID {
			self.sync.write().on_peer_aborting(&mut NetSyncIo::new(io, &*self.chain, &*self.snapshot_service, &self.overlay), *peer);
		}
	}

	fn timeout(&self, io: &NetworkContext, _timer: TimerToken) {
		self.sync.write().maintain_peers(&mut NetSyncIo::new(io, &*self.chain, &*self.snapshot_service, &self.overlay));
		self.sync.write().maintain_sync(&mut NetSyncIo::new(io, &*self.chain, &*self.snapshot_service, &self.overlay));
		self.sync.write().propagate_new_transactions(&mut NetSyncIo::new(io, &*self.chain, &*self.snapshot_service, &self.overlay));
	}
}

impl ChainNotify for EthSync {
	fn new_blocks(&self,
		imported: Vec<H256>,
		invalid: Vec<H256>,
		enacted: Vec<H256>,
		retracted: Vec<H256>,
		sealed: Vec<H256>,
		proposed: Vec<Bytes>,
		_duration: u64)
	{
		use light::net::Announcement;

		self.network.with_context(self.subprotocol_name, |context| {
			let mut sync_io = NetSyncIo::new(context, &*self.eth_handler.chain, &*self.eth_handler.snapshot_service, &self.eth_handler.overlay);
			self.eth_handler.sync.write().chain_new_blocks(
				&mut sync_io,
				&imported,
				&invalid,
				&enacted,
				&retracted,
				&sealed,
				&proposed);
		});

		self.network.with_context(self.light_subprotocol_name, |context| {
			let light_proto = match self.light_proto.as_ref() {
				Some(lp) => lp,
				None => return,
			};

			let chain_info = self.eth_handler.chain.chain_info();
			light_proto.make_announcement(context, Announcement {
				head_hash: chain_info.best_block_hash,
				head_num: chain_info.best_block_number,
				head_td: chain_info.total_difficulty,
				reorg_depth: 0, // recalculated on a per-peer basis.
				serve_headers: false, // these fields consist of _changes_ in capability.
				serve_state_since: None,
				serve_chain_since: None,
				tx_relay: false,
			})
		})
	}

	fn start(&self) {
		match self.network.start() {
			Err(NetworkError::StdIo(ref e)) if  e.kind() == io::ErrorKind::AddrInUse => warn!("Network port {:?} is already in use, make sure that another instance of an Ethereum client is not running or change the port using the --port option.", self.network.config().listen_address.expect("Listen address is not set.")),
			Err(err) => warn!("Error starting network: {}", err),
			_ => {},
		}
		self.network.register_protocol(self.eth_handler.clone(), self.subprotocol_name, ETH_PACKET_COUNT, &[62u8, 63u8])
			.unwrap_or_else(|e| warn!("Error registering ethereum protocol: {:?}", e));
		// register the warp sync subprotocol
		self.network.register_protocol(self.eth_handler.clone(), WARP_SYNC_PROTOCOL_ID, SNAPSHOT_SYNC_PACKET_COUNT, &[1u8, 2u8])
			.unwrap_or_else(|e| warn!("Error registering snapshot sync protocol: {:?}", e));

		// register the light protocol.
		if let Some(light_proto) = self.light_proto.as_ref().map(|x| x.clone()) {
			self.network.register_protocol(light_proto, self.light_subprotocol_name, ::light::net::PACKET_COUNT, ::light::net::PROTOCOL_VERSIONS)
				.unwrap_or_else(|e| warn!("Error registering light client protocol: {:?}", e));
		}
	}

	fn stop(&self) {
		self.eth_handler.snapshot_service.abort_restore();
		self.network.stop().unwrap_or_else(|e| warn!("Error stopping network: {:?}", e));
	}

	fn broadcast(&self, message: Vec<u8>) {
		self.network.with_context(WARP_SYNC_PROTOCOL_ID, |context| {
			let mut sync_io = NetSyncIo::new(context, &*self.eth_handler.chain, &*self.eth_handler.snapshot_service, &self.eth_handler.overlay);
			self.eth_handler.sync.write().propagate_consensus_packet(&mut sync_io, message.clone());
		});
	}

	fn transactions_received(&self, hashes: Vec<H256>, peer_id: PeerId) {
		let mut sync = self.eth_handler.sync.write();
		sync.transactions_received(hashes, peer_id);
	}
}

/// LES event handler.
/// Simply queues transactions from light client peers.
struct TxRelay(Arc<BlockChainClient>);

impl LightHandler for TxRelay {
	fn on_transactions(&self, ctx: &EventContext, relay: &[::ethcore::transaction::UnverifiedTransaction]) {
		trace!(target: "les", "Relaying {} transactions from peer {}", relay.len(), ctx.peer());
		self.0.queue_transactions(relay.iter().map(|tx| ::rlp::encode(tx).to_vec()).collect(), ctx.peer())
	}
}

impl IpcConfig for ManageNetwork { }
impl IpcConfig for SyncProvider { }

/// Trait for managing network
pub trait ManageNetwork : Send + Sync {
	/// Set to allow unreserved peers to connect
	fn accept_unreserved_peers(&self);
	/// Set to deny unreserved peers to connect
	fn deny_unreserved_peers(&self);
	/// Remove reservation for the peer
	fn remove_reserved_peer(&self, peer: String) -> Result<(), String>;
	/// Add reserved peer
	fn add_reserved_peer(&self, peer: String) -> Result<(), String>;
	/// Start network
	fn start_network(&self);
	/// Stop network
	fn stop_network(&self);
	/// Query the current configuration of the network
	fn network_config(&self) -> NetworkConfiguration;
}


#[cfg_attr(feature = "ipc", ipc(client_ident="NetworkManagerClient"))]
impl ManageNetwork for EthSync {
	fn accept_unreserved_peers(&self) {
		self.network.set_non_reserved_mode(NonReservedPeerMode::Accept);
	}

	fn deny_unreserved_peers(&self) {
		self.network.set_non_reserved_mode(NonReservedPeerMode::Deny);
	}

	fn remove_reserved_peer(&self, peer: String) -> Result<(), String> {
		self.network.remove_reserved_peer(&peer).map_err(|e| format!("{:?}", e))
	}

	fn add_reserved_peer(&self, peer: String) -> Result<(), String> {
		self.network.add_reserved_peer(&peer).map_err(|e| format!("{:?}", e))
	}

	fn start_network(&self) {
		self.start();
	}

	fn stop_network(&self) {
		self.network.with_context(self.subprotocol_name, |context| {
			let mut sync_io = NetSyncIo::new(context, &*self.eth_handler.chain, &*self.eth_handler.snapshot_service, &self.eth_handler.overlay);
			self.eth_handler.sync.write().abort(&mut sync_io);
		});

		if let Some(light_proto) = self.light_proto.as_ref() {
			light_proto.abort();
		}

		self.stop();
	}

	fn network_config(&self) -> NetworkConfiguration {
		NetworkConfiguration::from(self.network.config().clone())
	}
}

/// IP fiter
#[derive(Clone, Debug, PartialEq, Eq)]
#[cfg_attr(feature = "ipc", binary)]
pub enum AllowIP {
	/// Connect to any address
	All,
	/// Connect to private network only
	Private,
	/// Connect to public network only
	Public,
}

impl AllowIP {
	/// Attempt to parse the peer mode from a string.
	pub fn parse(s: &str) -> Option<Self> {
		match s {
			"all" => Some(AllowIP::All),
			"private" => Some(AllowIP::Private),
			"public" => Some(AllowIP::Public),
			_ => None,
		}
	}
}

#[derive(Debug, Clone, PartialEq, Eq)]
#[cfg_attr(feature = "ipc", binary)]
/// Network service configuration
pub struct NetworkConfiguration {
	/// Directory path to store general network configuration. None means nothing will be saved
	pub config_path: Option<String>,
	/// Directory path to store network-specific configuration. None means nothing will be saved
	pub net_config_path: Option<String>,
	/// IP address to listen for incoming connections. Listen to all connections by default
	pub listen_address: Option<String>,
	/// IP address to advertise. Detected automatically if none.
	pub public_address: Option<String>,
	/// Port for UDP connections, same as TCP by default
	pub udp_port: Option<u16>,
	/// Enable NAT configuration
	pub nat_enabled: bool,
	/// Enable discovery
	pub discovery_enabled: bool,
	/// List of initial node addresses
	pub boot_nodes: Vec<String>,
	/// Use provided node key instead of default
	pub use_secret: Option<Secret>,
	/// Max number of connected peers to maintain
	pub max_peers: u32,
	/// Min number of connected peers to maintain
	pub min_peers: u32,
	/// Max pending peers.
	pub max_pending_peers: u32,
	/// Reserved snapshot sync peers.
	pub snapshot_peers: u32,
	/// List of reserved node addresses.
	pub reserved_nodes: Vec<String>,
	/// The non-reserved peer mode.
	pub allow_non_reserved: bool,
	/// IP Filtering
	pub allow_ips: AllowIP,
}

impl NetworkConfiguration {
	/// Create a new default config.
	pub fn new() -> Self {
		From::from(BasicNetworkConfiguration::new())
	}

	/// Create a new local config.
	pub fn new_local() -> Self {
		From::from(BasicNetworkConfiguration::new_local())
	}

	/// Attempt to convert this config into a BasicNetworkConfiguration.
	pub fn into_basic(self) -> Result<BasicNetworkConfiguration, AddrParseError> {
		Ok(BasicNetworkConfiguration {
			config_path: self.config_path,
			net_config_path: self.net_config_path,
			listen_address: match self.listen_address { None => None, Some(addr) => Some(SocketAddr::from_str(&addr)?) },
			public_address:  match self.public_address { None => None, Some(addr) => Some(SocketAddr::from_str(&addr)?) },
			udp_port: self.udp_port,
			nat_enabled: self.nat_enabled,
			discovery_enabled: self.discovery_enabled,
			boot_nodes: self.boot_nodes,
			use_secret: self.use_secret,
			max_peers: self.max_peers,
			min_peers: self.min_peers,
			max_handshakes: self.max_pending_peers,
			reserved_protocols: hash_map![WARP_SYNC_PROTOCOL_ID => self.snapshot_peers],
			reserved_nodes: self.reserved_nodes,
			allow_ips: match self.allow_ips {
				AllowIP::All => NetworkAllowIP::All,
				AllowIP::Private => NetworkAllowIP::Private,
				AllowIP::Public => NetworkAllowIP::Public,
			},
			non_reserved_mode: if self.allow_non_reserved { NonReservedPeerMode::Accept } else { NonReservedPeerMode::Deny },
		})
	}
}

impl From<BasicNetworkConfiguration> for NetworkConfiguration {
	fn from(other: BasicNetworkConfiguration) -> Self {
		NetworkConfiguration {
			config_path: other.config_path,
			net_config_path: other.net_config_path,
			listen_address: other.listen_address.and_then(|addr| Some(format!("{}", addr))),
			public_address: other.public_address.and_then(|addr| Some(format!("{}", addr))),
			udp_port: other.udp_port,
			nat_enabled: other.nat_enabled,
			discovery_enabled: other.discovery_enabled,
			boot_nodes: other.boot_nodes,
			use_secret: other.use_secret,
			max_peers: other.max_peers,
			min_peers: other.min_peers,
			max_pending_peers: other.max_handshakes,
			snapshot_peers: *other.reserved_protocols.get(&WARP_SYNC_PROTOCOL_ID).unwrap_or(&0),
			reserved_nodes: other.reserved_nodes,
			allow_ips: match other.allow_ips {
				NetworkAllowIP::All => AllowIP::All,
				NetworkAllowIP::Private => AllowIP::Private,
				NetworkAllowIP::Public => AllowIP::Public,
			},
			allow_non_reserved: match other.non_reserved_mode { NonReservedPeerMode::Accept => true, _ => false } ,
		}
	}
}

/// Configuration for IPC service.
#[derive(Debug, Clone)]
#[cfg_attr(feature = "ipc", binary)]
pub struct ServiceConfiguration {
	/// Sync config.
	pub sync: SyncConfig,
	/// Network configuration.
	pub net: NetworkConfiguration,
	/// IPC path.
	pub io_path: String,
}

/// Configuration for the light sync.
pub struct LightSyncParams<L> {
	/// Network configuration.
	pub network_config: BasicNetworkConfiguration,
	/// Light client to sync to.
	pub client: Arc<L>,
	/// Network ID.
	pub network_id: u64,
	/// Subprotocol name.
	pub subprotocol_name: [u8; 3],
}

/// Service for light synchronization.
pub struct LightSync {
	proto: Arc<LightProtocol>,
	network: NetworkService,
	subprotocol_name: [u8; 3],
}

impl LightSync {
	/// Create a new light sync service.
	pub fn new<L>(params: LightSyncParams<L>) -> Result<Self, NetworkError>
		where L: LightChainClient + Provider + 'static
	{
		use light_sync::LightSync as SyncHandler;

		// initialize light protocol handler and attach sync module.
		let light_proto = {
			let light_params = LightParams {
				network_id: params.network_id,
				flow_params: Default::default(), // or `None`?
				capabilities: Capabilities {
					serve_headers: false,
					serve_chain_since: None,
					serve_state_since: None,
					tx_relay: false,
				},
			};

			let mut light_proto = LightProtocol::new(params.client.clone(), light_params);
			let sync_handler = try!(SyncHandler::new(params.client.clone()));
			light_proto.add_handler(Arc::new(sync_handler));

			Arc::new(light_proto)
		};

		let service = try!(NetworkService::new(params.network_config));

		Ok(LightSync {
			proto: light_proto,
			network: service,
			subprotocol_name: params.subprotocol_name,
		})
	}
}

impl ManageNetwork for LightSync {
	fn accept_unreserved_peers(&self) {
		self.network.set_non_reserved_mode(NonReservedPeerMode::Accept);
	}

	fn deny_unreserved_peers(&self) {
		self.network.set_non_reserved_mode(NonReservedPeerMode::Deny);
	}

	fn remove_reserved_peer(&self, peer: String) -> Result<(), String> {
		self.network.remove_reserved_peer(&peer).map_err(|e| format!("{:?}", e))
	}

	fn add_reserved_peer(&self, peer: String) -> Result<(), String> {
		self.network.add_reserved_peer(&peer).map_err(|e| format!("{:?}", e))
	}

	fn start_network(&self) {
		match self.network.start() {
			Err(NetworkError::StdIo(ref e)) if  e.kind() == io::ErrorKind::AddrInUse => warn!("Network port {:?} is already in use, make sure that another instance of an Ethereum client is not running or change the port using the --port option.", self.network.config().listen_address.expect("Listen address is not set.")),
			Err(err) => warn!("Error starting network: {}", err),
			_ => {},
		}

		let light_proto = self.proto.clone();

		self.network.register_protocol(light_proto, self.subprotocol_name, ::light::net::PACKET_COUNT, ::light::net::PROTOCOL_VERSIONS)
			.unwrap_or_else(|e| warn!("Error registering light client protocol: {:?}", e));
	}

	fn stop_network(&self) {
		self.proto.abort();
		if let Err(e) = self.network.stop() {
			warn!("Error stopping network: {}", e);
		}
	}

	fn network_config(&self) -> NetworkConfiguration {
		NetworkConfiguration::from(self.network.config().clone())
	}
}