LBRYCommunity/lbcd
1
0
Fork 0
Code Issues 17 Pull requests 4 Packages Projects Releases 28 Wiki Activity

Flesh out addrmanger with some basic functionality.

Browse source 
Use it to add multiple peer support. We try and keep 8 outbound peers
active at all times.

This address manager is not as complete as the one in bitcoind yet, but
additional functionality is being worked on.

We currently handle (in a similar manner to bitcoind):

- biasing between new and already tried addresses based on number of connected
  peers.
- rejection of non-default ports until desparate
- address selection probabilities based on last successful connection and number
  of failures.
- routability checks based on known unroutable subnets.
- only connecting to each network `group' once at any one time.

We currently lack support for:
- tor ``addresses'' (an .onion address encoded in 64 bytes of ip address)
- full state save and restore (we just save a json with the list of known
  addresses in it)
- multiple buckets for new and tried addresses selected by a hash of address and
 source.  The current algorithm functions the same as bitcoind would with only
 one bucket for new and tried (making the address cache rather smaller than it
 otherwise would be).
This commit is contained in:
Owain G. Ainsworth 2013-08-01 18:00:14 +01:00 committed by Dave Collins
parent 79bb334b9a
commit 6c05e9d475
5 changed files with 1060 additions and 188 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

754
addrmanager.go
View file

@ -5,8 +5,13 @@
package main
import (
"container/list"
"encoding/json"
"github.com/conformal/btcwire"
"math"
"math/rand"
"net"
"os"
"strconv"
"sync"
"time"
@ -17,53 +22,235 @@ const (
// address manager will track.
maxAddresses = 2500
newAddressBufferSize = 50
dumpAddressInterval = time.Minute * 2
// dumpAddressInterval is the interval used to dump the address
// cache to disk for future use.
dumpAddressInterval = time.Minute * 2
// triedBucketSize is the maximum number of addresses in each
// tried address bucket.
triedBucketSize = 64
// newBucketSize is the maximum number of addresses in each new address
// bucket.
newBucketSize = 64
// numMissingDays is the number of days before which we assume an
// address has vanished if we have not seen it announced in that long.
numMissingDays = 30
// numRetries is the number of tried without a single success before
// we assume an address is bad.
numRetries = 3
// maxFailures is the maximum number of failures we will accept without
// a success before considering an address bad.
maxFailures = 10
// minBadDays is the number of days since the last success before we
// will consider evicting an address.
minBadDays = 7
)
// updateAddress is a helper function to either update an address already known
// to the address manager, or to add the address if not already known.
func updateAddress(a *AddrManager, netAddr *btcwire.NetAddress) {
func (a *AddrManager) updateAddress(netAddr, srcAddr *btcwire.NetAddress) {
// Protect concurrent access.
a.addrCacheLock.Lock()
defer a.addrCacheLock.Unlock()
a.mtx.Lock()
defer a.mtx.Unlock()
// Update address if it already exists.
addr := NetAddressKey(netAddr)
if na, ok := a.addrCache[addr]; ok {
ka := a.find(netAddr)
if ka != nil {
// Update the last seen time.
if netAddr.Timestamp.After(na.Timestamp) {
na.Timestamp = netAddr.Timestamp
if netAddr.Timestamp.After(ka.na.Timestamp) {
ka.na.Timestamp = netAddr.Timestamp
}
// Update services.
na.AddService(na.Services)
ka.na.AddService(netAddr.Services)
log.Tracef("[AMGR] Updated address manager address %s", addr)
log.Tracef("[AMGR] Updated address manager address %s",
NetAddressKey(netAddr))
return
}
// Enforce max addresses.
if len(a.addrCache)+1 > maxAddresses {
log.Tracef("[AMGR] Max addresses of %d reached", maxAddresses)
return
if len(a.addrNew) > newBucketSize {
log.Tracef("[AMGR] new bucket is full, expiring old ")
a.expireNew()
}
a.addrCache[addr] = netAddr
addr := NetAddressKey(netAddr)
ka = &knownAddress{na: netAddr}
// Fill in index.
a.addrIndex[addr] = ka
// Add to new bucket.
a.addrNew[addr] = ka
log.Tracef("[AMGR] Added new address %s for a total of %d addresses",
addr, len(a.addrCache))
addr, len(a.addrNew)+a.addrTried.Len())
}
// bad returns true if the address in question has not been tried in the last
// minute and meets one of the following
// criteria:
// 1) It claims to be from the future.
// 2) It hasn't been seen in over a month.
// 3) It has failed at least three times and never succeeded.
// 4) It has failed ten times in the last week.
// All addresses that meet these criteria are assumed to be worthless and not
// worth keeping hold of.
func bad(ka *knownAddress) bool {
if ka.lastattempt.After(time.Now().Add(-1 * time.Minute)) {
return false
}
// From the future?
if ka.na.Timestamp.After(time.Now().Add(10 * time.Minute)) {
return true
}
// Over a month old?
if ka.na.Timestamp.After(time.Now().Add(-1 * numMissingDays * time.Hour * 24)) {
return true
}
// Never succeeded?
if ka.lastsuccess.IsZero() && ka.attempts >= numRetries {
return true
}
// Hasn't succeeded in too long?
if !ka.lastsuccess.After(time.Now().Add(-1*minBadDays*time.Hour*24)) &&
ka.attempts >= maxFailures {
return true
}
return false
}
// chance returns the selection probability for a known address. The priority
// depends upon how recent the address has been seen, how recent it was last
// attempted and how often attempts to connect to it have failed.
func chance(ka *knownAddress) float64 {
c := 1.0
now := time.Now()
var lastSeen float64 = 0.0
var lastTry float64 = 0.0
if !ka.na.Timestamp.After(now) {
var dur time.Duration
if ka.na.Timestamp.IsZero() {
// use unix epoch to match bitcoind.
dur = now.Sub(time.Unix(0, 0))
} else {
dur = now.Sub(ka.na.Timestamp)
}
lastSeen = dur.Seconds()
}
if !ka.lastattempt.After(now) {
var dur time.Duration
if ka.lastattempt.IsZero() {
// use unix epoch to match bitcoind.
dur = now.Sub(time.Unix(0, 0))
} else {
dur = now.Sub(ka.lastattempt)
}
lastTry = dur.Seconds()
}
c = 600.0 / (600.0 + lastSeen)
// very recent attempts are less likely to be retried.
if lastTry > 60.0*10.0 {
c *= 0.01
}
// failed attempts deprioritise
if ka.attempts > 0 {
c /= (float64(ka.attempts) * 1.5)
}
return c
}
// expireNew makes space in the new buckets by expiring the really bad entries.
// If no bad entries are available we look at a few and remove the oldest.
func (a *AddrManager) expireNew() {
// First see if there are any entries that are so bad we can just throw
// them away. otherwise we throw away the oldest entry in the cache.
// Bitcoind here chooses four random and just throws the oldest of
// those away, but we keep track of oldest in the initial traversal and
// use that information instead
var oldest *knownAddress
for k, v := range a.addrNew {
if bad(v) {
log.Tracef("[AMGR] expiring bad address %v", k)
delete(a.addrIndex, k)
delete(a.addrNew, k)
return
}
if oldest == nil {
oldest = v
} else if !v.na.Timestamp.After(oldest.na.Timestamp) {
oldest = v
}
}
if oldest != nil {
key := NetAddressKey(oldest.na)
log.Tracef("[AMGR] expiring oldest address %v", key)
delete(a.addrIndex, key)
delete(a.addrNew, key)
}
}
// pickTried selects an address from the tried bucket to be evicted.
// We just choose the eldest.
func (a *AddrManager) pickTried() *list.Element {
var oldest *knownAddress
var oldestElem *list.Element
for e := a.addrTried.Front(); e != nil; e = e.Next() {
ka := e.Value.(*knownAddress)
if oldest == nil || oldest.na.Timestamp.After(ka.na.Timestamp) {
oldestElem = e
oldest = ka
}
}
return oldestElem
}
type knownAddress struct {
na *btcwire.NetAddress
attempts int
lastattempt time.Time
lastsuccess time.Time
time time.Time
tried bool
}
// AddrManager provides a concurrency safe address manager for caching potential
// peers on the bitcoin network.
type AddrManager struct {
addrCache map[string]*btcwire.NetAddress
addrCacheLock sync.Mutex
started bool
shutdown bool
newAddresses chan []*btcwire.NetAddress
removeAddresses chan []*btcwire.NetAddress
wg sync.WaitGroup
quit chan bool
mtx sync.Mutex
rand *rand.Rand
addrIndex map[string]*knownAddress // address key to ka for all addrs.
addrNew map[string]*knownAddress
addrTried *list.List
started bool
shutdown bool
wg sync.WaitGroup
quit chan bool
}
type JsonSave struct {
AddrList []string
}
// addressHandler is the main handler for the address manager. It must be run
@ -73,18 +260,13 @@ func (a *AddrManager) addressHandler() {
out:
for !a.shutdown {
select {
case addrs := <-a.newAddresses:
for _, na := range addrs {
updateAddress(a, na)
}
case <-dumpAddressTicker.C:
if !a.shutdown {
// TODO: Dump addresses to database.
a.savePeers()
}
case <-a.quit:
// TODO: Dump addresses to database.
a.savePeers()
break out
}
}
@ -93,6 +275,63 @@ out:
log.Trace("[AMGR] Address handler done")
}
// savePeers saves all the known addresses to a file so they can be read back
// in at next run.
func (a *AddrManager) savePeers() {
// May give some way to specify this later.
filename := "peers.json"
var toSave JsonSave
list := a.AddressCacheFlat()
log.Info("LIST ", list)
toSave.AddrList = list
w, err := os.Create(filename)
if err != nil {
log.Error("Error opening file: ", filename, err)
}
enc := json.NewEncoder(w)
defer w.Close()
enc.Encode(&toSave)
log.Info("Saving peer list.")
}
// loadPeers loads the known address from the saved file. If empty, missing, or
// malformed file, just don't load anything and start fresh
func (a *AddrManager) loadPeers() {
log.Info("Loading saved peers")
// May give some way to specify this later.
filename := "peers.json"
_, err := os.Stat(filename)
if os.IsNotExist(err) {
log.Debugf("%s does not exist.\n", filename)
} else {
r, err := os.Open(filename)
if err != nil {
log.Error("Error opening file: ", filename, err)
return
}
defer r.Close()
var inList JsonSave
dec := json.NewDecoder(r)
err = dec.Decode(&inList)
if err != nil {
log.Error("Error reading:", filename, err)
return
}
log.Debug("Adding ", len(inList.AddrList), " saved peers.")
if len(inList.AddrList) > 0 {
for _, ip := range inList.AddrList {
a.AddAddressByIP(ip)
}
}
}
}
// Start begins the core address handler which manages a pool of known
// addresses, timeouts, and interval based writes.
func (a *AddrManager) Start() {
@ -106,6 +345,9 @@ func (a *AddrManager) Start() {
a.wg.Add(1)
go a.addressHandler()
a.started = true
// Load peers we already know about from file.
a.loadPeers()
}
// Stop gracefully shuts down the address manager by stopping the main handler.
@ -117,6 +359,7 @@ func (a *AddrManager) Stop() error {
}
log.Infof("[AMGR] Address manager shutting down")
a.savePeers()
a.shutdown = true
a.quit <- true
a.wg.Wait()
@ -126,50 +369,115 @@ func (a *AddrManager) Stop() error {
// AddAddresses adds new addresses to the address manager. It enforces a max
// number of addresses and silently ignores duplicate addresses. It is
// safe for concurrent access.
func (a *AddrManager) AddAddresses(addrs []*btcwire.NetAddress) {
a.newAddresses <- addrs
func (a *AddrManager) AddAddresses(addrs []*btcwire.NetAddress,
srcAddr *btcwire.NetAddress) {
for _, na := range addrs {
// Filter out non-routable addresses. Note that non-routable
// also includes invalid and local addresses.
if Routable(na) {
a.updateAddress(na, srcAddr)
}
}
}
// AddAddress adds a new address to the address manager. It enforces a max
// number of addresses and silently ignores duplicate addresses. It is
// safe for concurrent access.
func (a *AddrManager) AddAddress(addr *btcwire.NetAddress) {
addrs := []*btcwire.NetAddress{addr}
a.newAddresses <- addrs
func (a *AddrManager) AddAddress(addr *btcwire.NetAddress,
srcAddr *btcwire.NetAddress) {
a.AddAddresses([]*btcwire.NetAddress{addr}, srcAddr)
}
// AddAddressByIP adds an address where we are given an ip:port and not a
// btcwire.NetAddress.
func (a *AddrManager) AddAddressByIP(addrIP string) {
// Split IP and port
addr, portStr, err := net.SplitHostPort(addrIP)
if err != nil {
log.Warnf("[AMGR] AddADddressByIP given bullshit adddress"+
"(%s): %v", err)
return
}
// Put it in btcwire.Netaddress
var na btcwire.NetAddress
na.Timestamp = time.Now()
na.IP = net.ParseIP(addr)
if na.IP == nil {
log.Error("Invalid ip address:", addr)
return
}
port, err := strconv.ParseUint(portStr, 10, 0)
if err != nil {
log.Error("Invalid port: ", portStr, err)
return
}
na.Port = uint16(port)
a.AddAddress(&na, &na) // XXX use correct src address
}
// NeedMoreAddresses returns whether or not the address manager needs more
// addresses.
func (a *AddrManager) NeedMoreAddresses() bool {
// Protect concurrent access.
a.addrCacheLock.Lock()
defer a.addrCacheLock.Unlock()
// NumAddresses handles concurrent access for us.
return len(a.addrCache)+1 <= maxAddresses
return a.NumAddresses()+1 <= maxAddresses
}
// NumAddresses returns the number of addresses known to the address manager.
func (a *AddrManager) NumAddresses() int {
// Protect concurrent access.
a.addrCacheLock.Lock()
defer a.addrCacheLock.Unlock()
a.mtx.Lock()
defer a.mtx.Unlock()
return len(a.addrCache)
return len(a.addrNew) + a.addrTried.Len()
}
// AddressCache returns the current address cache. It must be treated as
// read-only.
// read-only (but since it is a copy now, this is not as dangerous).
func (a *AddrManager) AddressCache() map[string]*btcwire.NetAddress {
return a.addrCache
allAddr := make(map[string]*btcwire.NetAddress)
a.mtx.Lock()
defer a.mtx.Unlock()
for k, v := range a.addrNew {
allAddr[k] = v.na
}
for e := a.addrTried.Front(); e != nil; e = e.Next() {
ka := e.Value.(*knownAddress)
allAddr[NetAddressKey(ka.na)] = ka.na
}
return allAddr
}
// AddressCacheFlat returns a flat list of strings with the current address
// cache. Just a copy, so one can do whatever they want to it.
func (a *AddrManager) AddressCacheFlat() []string {
var allAddr []string
a.mtx.Lock()
defer a.mtx.Unlock()
for k, _ := range a.addrNew {
allAddr = append(allAddr, k)
}
for e := a.addrTried.Front(); e != nil; e = e.Next() {
ka := e.Value.(*knownAddress)
allAddr = append(allAddr, NetAddressKey(ka.na))
}
return allAddr
}
// New returns a new bitcoin address manager.
// Use Start to begin processing asynchronous address updates.
func NewAddrManager() *AddrManager {
am := AddrManager{
addrCache: make(map[string]*btcwire.NetAddress),
newAddresses: make(chan []*btcwire.NetAddress, newAddressBufferSize),
quit: make(chan bool),
rand: rand.New(rand.NewSource(time.Now().UnixNano())),
addrIndex: make(map[string]*knownAddress),
addrNew: make(map[string]*knownAddress),
addrTried: list.New(),
quit: make(chan bool),
}
return &am
}
@ -181,3 +489,351 @@ func NetAddressKey(na *btcwire.NetAddress) string {
addr := net.JoinHostPort(na.IP.String(), port)
return addr
}
// GetAddress returns a single address that should be routable. It picks a
// random one from the possible addresses with preference given to ones that
// have not been used recently and should not pick 'close' addresses
// consecutively.
func (a *AddrManager) GetAddress(class string, newBias int) *knownAddress {
// Protect concurrent access.
a.mtx.Lock()
defer a.mtx.Unlock()
if newBias > 100 {
newBias = 100
}
if newBias < 0 {
newBias = 0
}
// Bias 50% for now between new and tried.
triedCorrelation := math.Sqrt(float64(a.addrTried.Len())) *
(100.0 - float64(newBias))
newCorrelation := math.Sqrt(float64(len(a.addrNew))) * float64(newBias)
if (newCorrelation+triedCorrelation)*a.rand.Float64() <
triedCorrelation {
// Tried entry.
large := 1 << 30
factor := 1.0
for {
// Pick a random entry in the list
e := a.addrTried.Front()
for i := a.rand.Int63n(int64(a.addrTried.Len()));
i > 0; i-- {
e = e.Next()
}
ka := e.Value.(*knownAddress)
randval := a.rand.Intn(large)
if float64(randval) < (factor * chance(ka) * float64(large)) {
log.Tracef("[AMGR] Selected %v from tried "+
"bucket", NetAddressKey(ka.na))
return ka
}
factor *= 1.2
}
} else {
// new node.
// XXX use a closure/function to avoid repeating this.
keyList := []string{}
for key := range a.addrNew {
keyList = append(keyList, key)
}
large := 1 << 30
factor := 1.0
for {
testKey := keyList[a.rand.Int63n(int64(len(keyList)))]
ka := a.addrNew[testKey]
randval := a.rand.Intn(large)
if float64(randval) < (factor * chance(ka) * float64(large)) {
log.Tracef("[AMGR] Selected %v from new bucket",
NetAddressKey(ka.na))
return ka
}
factor *= 1.2
}
}
return nil
}
func (a *AddrManager) find(addr *btcwire.NetAddress) *knownAddress {
return a.addrIndex[NetAddressKey(addr)]
}
/*
* Connected - updates the last seen time but only every 20 minutes.
* Good - last tried = last success = last seen = now. attmempts = 0.
* - move address to tried.
* Attempted - set last tried to time. nattempts++
*/
func (a *AddrManager) Attempt(addr *btcwire.NetAddress) {
a.mtx.Lock()
defer a.mtx.Unlock()
// find address.
// Surely address will be in tried by now?
ka := a.find(addr)
if ka == nil {
return
}
// set last tried time to now
ka.attempts++
ka.lastattempt = time.Now()
}
// Connected Marks the given address as currently connected and working at the
// current time. The address must already be known to AddrManager else it will
// be ignored.
func (a *AddrManager) Connected(addr *btcwire.NetAddress) {
a.mtx.Lock()
defer a.mtx.Unlock()
ka := a.find(addr)
if ka == nil {
return
}
// Update the time as long as it has been 20 minutes since last we did
// so.
now := time.Now()
if now.After(ka.na.Timestamp.Add(time.Minute * 20)) {
ka.na.Timestamp = time.Now()
}
}
// Good marks the given address as good. To be called after a successful
// connection and version exchange. If the address is unkownto the addresss
// manager it will be ignored.
func (a *AddrManager) Good(addr *btcwire.NetAddress) {
a.mtx.Lock()
defer a.mtx.Unlock()
ka := a.find(addr)
if ka == nil {
return
}
now := time.Now()
ka.lastsuccess = now
ka.lastattempt = now
ka.na.Timestamp = now
ka.attempts = 0
// move to tried set, optionally evicting other addresses if neeed.
if ka.tried {
return
}
// ok, need to move it to tried.
// remove from new buckets.
addrKey := NetAddressKey(addr)
delete(a.addrNew, addrKey)
// is tried full? or is it ok?
if a.addrTried.Len() < triedBucketSize {
a.addrTried.PushBack(ka)
return
}
// No room, we have to evict something else.
// pick another one to throw out
entry := a.pickTried()
rmka := entry.Value.(*knownAddress)
rmkey := NetAddressKey(rmka.na)
// replace with ka.
entry.Value = ka
rmka.tried = false
log.Tracef("[AMGR] replacing %s with %s in tried", rmkey, addrKey)
// We know there is space for it since we just moved out of new.
// TODO(oga) when we move to multiple buckets then we will need to
// check for size and consider putting it elsewhere.
a.addrNew[rmkey] = rmka
}
// RFC1918: IPv4 Private networks (10.0.0.0/8, 192.168.0.0/16, 172.16.0.0/12)
var rfc1918ten = net.IPNet{IP: net.ParseIP("10.0.0.0"),
Mask: net.CIDRMask(8, 32)}
var rfc1918oneninetwo = net.IPNet{IP: net.ParseIP("192.168.0.0"),
Mask: net.CIDRMask(16, 32)}
var rfc1918oneseventwo = net.IPNet{IP: net.ParseIP("172.16.0.0"),
Mask: net.CIDRMask(12, 32)}
func RFC1918(na *btcwire.NetAddress) bool {
return rfc1918ten.Contains(na.IP) ||
rfc1918oneninetwo.Contains(na.IP) ||
rfc1918oneseventwo.Contains(na.IP)
}
// RFC3849 IPv6 Documentation address (2001:0DB8::/32)
var rfc3849 = net.IPNet{IP: net.ParseIP("2001:0DB8::"),
Mask: net.CIDRMask(32, 128)}
func RFC3849(na *btcwire.NetAddress) bool {
return rfc3849.Contains(na.IP)
}
// RFC3927 IPv4 Autoconfig (169.254.0.0/16)
var rfc3927 = net.IPNet{IP: net.ParseIP("169.254.0.0"), Mask: net.CIDRMask(16, 32)}
func RFC3927(na *btcwire.NetAddress) bool {
return rfc3927.Contains(na.IP)
}
// RFC3964 IPv6 6to4 (2002::/16)
var rfc3964 = net.IPNet{IP: net.ParseIP("2002::"),
Mask: net.CIDRMask(16, 128)}
func RFC3964(na *btcwire.NetAddress) bool {
return rfc3964.Contains(na.IP)
}
// RFC4193 IPv6 unique local (FC00::/15)
var rfc4193 = net.IPNet{IP: net.ParseIP("FC00::"),
Mask: net.CIDRMask(15, 128)}
func RFC4193(na *btcwire.NetAddress) bool {
return rfc4193.Contains(na.IP)
}
// RFC4380 IPv6 Teredo tunneling (2001::/32)
var rfc4380 = net.IPNet{IP: net.ParseIP("2001::"),
Mask: net.CIDRMask(32, 128)}
func RFC4380(na *btcwire.NetAddress) bool {
return rfc4380.Contains(na.IP)
}
// RFC4843 IPv6 ORCHID: (2001:10::/28)
var rfc4843 = net.IPNet{IP: net.ParseIP("2001;10::"),
Mask: net.CIDRMask(28, 128)}
func RFC4843(na *btcwire.NetAddress) bool {
return rfc4843.Contains(na.IP)
}
// RFC4862 IPv6 Autoconfig (FE80::/64)
var rfc4862 = net.IPNet{IP: net.ParseIP("FE80::"),
Mask: net.CIDRMask(64, 128)}
func RFC4862(na *btcwire.NetAddress) bool {
return rfc4862.Contains(na.IP)
}
// RFC6052: IPv6 well known prefix (64:FF9B::/96)
var rfc6052 = net.IPNet{IP: net.ParseIP("64::FF9B::"),
Mask: net.CIDRMask(96, 128)}
func RFC6052(na *btcwire.NetAddress) bool {
return rfc6052.Contains(na.IP)
}
// RFC6145: IPv6 IPv4 translated address ::FFFF:0:0:0/96
var rfc6145 = net.IPNet{IP: net.ParseIP("::FFFF:0:0:0"),
Mask: net.CIDRMask(96, 128)}
func RFC6145(na *btcwire.NetAddress) bool {
return rfc6145.Contains(na.IP)
}
func Tor(na *btcwire.NetAddress) bool {
// bitcoind encodes a .onion address as a 16 byte number by decoding the
// address prior to the .onion (i.e. the key hash) base32 into a ten
// byte number. it then stores the first 6 bytes of the address as
// 0xfD, 0x87, 0xD8, 0x7e, 0xeb, 0x43
// making the format
// { magic 6 bytes, 10 bytes base32 decode of key hash }
// Since we use btcwire.NetAddress to represent and address we may
// well have to emulate this.
// XXX fillmein
return false
}
var zero4 = net.IPNet{IP: net.ParseIP("0.0.0.0"),
Mask: net.CIDRMask(8, 32)}
func Local(na *btcwire.NetAddress) bool {
return na.IP.IsLoopback() || zero4.Contains(na.IP)
}
// Valid returns true if an address is not one of the invalid formats.
// For IPv4 these are either a 0 or all bits set address. For IPv6 a zero
// address or one that matches the RFC3849 documentation address format.
func Valid(na *btcwire.NetAddress) bool {
// IsUnspecified returns if address is 0, so only all bits set, and
// RFC3849 need to be explicitly checked. bitcoind here also checks for
// invalid protocol addresses from earlier versions of bitcoind (before
// 0.2.9), however, since protocol versions before 70001 are
// disconnected by the bitcoin network now we have elided it.
return !(na.IP.IsUnspecified() || RFC3849(na) ||
na.IP.Equal(net.IPv4bcast))
}
// Routable returns whether a netaddress is routable on the public internet or
// not. This is true as long as the address is valid and is not in any reserved
// ranges.
func Routable(na *btcwire.NetAddress) bool {
return Valid(na) && !(RFC1918(na) || RFC3927(na) || RFC4862(na) ||
RFC4193(na) || Tor(na) || RFC4843(na) || Local(na))
}
// GroupKey returns a string representing the network group an address
// is part of.
// This is the /16 for IPv6, the /32 (/36 for he.net) for IPv6, the string
// "local" for a local address and the string "unroutable for an unroutable
// address.
func GroupKey(na *btcwire.NetAddress) string {
if Local(na) {
return "local"
}
if !Routable(na) {
return "unroutable"
}
if ipv4 := na.IP.To4(); ipv4 != nil {
return (&net.IPNet{IP: na.IP, Mask: net.CIDRMask(16, 32)}).String()
}
if RFC6145(na) || RFC6052(na) {
// last four bytes are the ip address
ip := net.IP(na.IP[12:16])
return (&net.IPNet{IP: ip, Mask: net.CIDRMask(16, 32)}).String()
}
if RFC3964(na) {
ip := net.IP(na.IP[2:7])
return (&net.IPNet{IP: ip, Mask: net.CIDRMask(16, 32)}).String()
}
if RFC4380(na) {
// teredo tunnels have the last 4 bytes as the v4 address XOR
// 0xff.
ip := net.IP(make([]byte, 4))
for i, byte := range na.IP[12:16] {
ip[i] = byte ^ 0xff
}
return (&net.IPNet{IP: ip, Mask: net.CIDRMask(16, 32)}).String()
}
// XXX tor?
if Tor(na) {
panic("oga should have implemented me")
}
// OK, so now we know ourselves to be a IPv6 address.
// bitcoind uses /32 for everything but what it calls he.net, which is
// it uses /36 for. he.net is actualy 2001:470::/32, whereas bitcoind
// counts it as 2011:470::/32.
bits := 32
heNet := &net.IPNet{IP: net.ParseIP("2011:470::"),
Mask: net.CIDRMask(32, 128)}
if heNet.Contains(na.IP) {
bits = 36
}
return (&net.IPNet{IP: na.IP, Mask: net.CIDRMask(bits, 128)}).String()
}

40
btcd.go
View file

@ -9,14 +9,10 @@ import (
"github.com/conformal/btcchain"
"github.com/conformal/btcdb"
"github.com/conformal/btcscript"
"github.com/conformal/btcwire"
"github.com/conformal/seelog"
"math/rand"
"net"
"os"
"runtime"
"strconv"
"time"
)
// These constants are used by the dns seed code to pick a random last seen
@ -142,42 +138,6 @@ func btcdMain() error {
}
server.Start()
// only ask dns for peers if we don't have a list of initial seeds.
if !cfg.DisableDNSSeed {
proxy := ""
if cfg.Proxy != "" && cfg.UseTor {
proxy = cfg.Proxy
}
seedpeers := dnsDiscover(activeNetParams.dnsSeeds, proxy)
addresses := make([]*btcwire.NetAddress, len(seedpeers))
// if this errors then we have *real* problems
intPort, _ := strconv.Atoi(activeNetParams.peerPort)
for i, peer := range seedpeers {
addresses[i] = new(btcwire.NetAddress)
addresses[i].SetAddress(peer, uint16(intPort))
// bitcoind seeds with addresses from
// a time randomly selected between 3
// and 7 days ago.
addresses[i].Timestamp = time.Now().Add(-1 *
time.Second * time.Duration(secondsIn3Days+
rand.Int31n(secondsIn4Days)))
}
server.addrManager.AddAddresses(addresses)
// XXX if this is empty do we want to use hardcoded
// XXX peers like bitcoind does?
}
peers := cfg.ConnectPeers
if len(peers) == 0 {
peers = cfg.AddPeers
}
// Connect to initial peers.
for _, addr := range peers {
// Connect to peer and add it to the server.
server.ConnectPeerAsync(addr, true)
}
server.WaitForShutdown()
return nil
}

26
discovery.go
View file

@ -149,22 +149,18 @@ func torLookupIP(host, proxy string) ([]net.IP, error) {
// resolution. If any errors occur then the seeder that errored will not have
// any hosts in the list. Therefore if all hosts failed an empty slice of
// strings will be returned.
func dnsDiscover(seeders []string, proxy string) []net.IP {
peers := []net.IP{}
for _, seeder := range seeders {
log.Debugf("[DISC] Fetching list of seeds from %v", seeder)
newPeers, err := doDNSLookup(seeder, proxy)
if err != nil {
seederPlusProxy := seeder
if proxy != "" {
seederPlusProxy = fmt.Sprintf("%s (proxy %s)",
seeder, proxy)
}
log.Warnf("[DISC] Failed to fetch dns seeds "+
"from %s: %v", seederPlusProxy, err)
continue
func dnsDiscover(seeder string, proxy string) []net.IP {
log.Debugf("[DISC] Fetching list of seeds from %v", seeder)
peers, err := doDNSLookup(seeder, proxy)
if err != nil {
seederPlusProxy := seeder
if proxy != "" {
seederPlusProxy = fmt.Sprintf("%s (proxy %s)",
seeder, proxy)
}
peers = append(peers, newPeers...)
log.Warnf("[DISC] Failed to fetch dns seeds "+
"from %s: %v", seederPlusProxy, err)
return []net.IP{}
}
return peers

151
peer.go
View file

@ -97,6 +97,8 @@ type peer struct {
services btcwire.ServiceFlag
started bool
conn net.Conn
addr string
na *btcwire.NetAddress
timeConnected time.Time
inbound bool
disconnect bool
@ -228,15 +230,15 @@ func (p *peer) handleVersionMsg(msg *btcwire.MsgVersion) {
p.Disconnect()
return
}
}
// Add inbound peer address to the server address manager.
na, err := btcwire.NewNetAddress(p.conn.RemoteAddr(), p.services)
if err != nil {
log.Errorf("[PEER] %v", err)
p.Disconnect()
return
}
p.server.addrManager.AddAddress(na)
var err error
// Set up a netaddress for the peer to be used with addrmanager..
p.na, err = newNetAddress(p.conn.RemoteAddr(), p.services)
if err != nil {
log.Errorf("[PEER] %v", err)
p.Disconnect()
return
}
// Send verack.
@ -263,10 +265,19 @@ func (p *peer) handleVersionMsg(msg *btcwire.MsgVersion) {
// Request known addresses if the server address manager needs
// more and the peer has a protocol version new enough to
// include a timestamp with addresses.
// XXX bitcoind only does this if we have < 1000 addresses, not
// the max of 2400
hasTimestamp := p.protocolVersion >= btcwire.NetAddressTimeVersion
if p.server.addrManager.NeedMoreAddresses() && hasTimestamp {
p.outputQueue <- btcwire.NewMsgGetAddr()
}
// Add inbound peer address to the server address manager.
p.server.addrManager.Good(p.na)
} else {
if NetAddressKey(&msg.AddrMe) == NetAddressKey(p.na) {
p.server.addrManager.AddAddress(p.na, p.na)
p.server.addrManager.Good(p.na)
}
}
// Signal the block manager this peer is a new sync candidate.
@ -758,7 +769,7 @@ func (p *peer) handleAddrMsg(msg *btcwire.MsgAddr) {
// Add addresses to server address manager. The address manager handles
// the details of things such as preventing duplicate addresses, max
// addresses, and last seen updates.
p.server.addrManager.AddAddresses(msg.AddrList)
p.server.addrManager.AddAddresses(msg.AddrList, p.na)
}
// handlePingMsg is invoked when a peer receives a ping bitcoin message. For
@ -882,10 +893,12 @@ out:
break out
}
markConnected := false
// Handle each supported message type.
switch msg := rmsg.(type) {
case *btcwire.MsgVersion:
p.handleVersionMsg(msg)
markConnected = true
case *btcwire.MsgVerAck:
// Do nothing.
@ -895,9 +908,11 @@ out:
case *btcwire.MsgAddr:
p.handleAddrMsg(msg)
markConnected = true
case *btcwire.MsgPing:
p.handlePingMsg(msg)
markConnected = true
case *btcwire.MsgPong:
// Don't do anything, but could try to work out network
@ -911,9 +926,11 @@ out:
case *btcwire.MsgInv:
p.handleInvMsg(msg)
markConnected = true
case *btcwire.MsgGetData:
p.handleGetDataMsg(msg)
markConnected = true
case *btcwire.MsgGetBlocks:
p.handleGetBlocksMsg(msg)
@ -925,6 +942,14 @@ out:
log.Debugf("[PEER] Received unhandled message of type %v: Fix Me",
rmsg.Command())
}
if markConnected && !p.disconnect {
if p.na == nil {
log.Warnf("we're getting stuff before we " +
"got a version message. that's bad")
continue
}
p.server.addrManager.Connected(p.na)
}
}
// Ensure connection is closed and notify server and block manager that
@ -1047,28 +1072,51 @@ func (p *peer) Start() error {
// a flag so the impending shutdown can be detected.
func (p *peer) Disconnect() {
p.disconnect = true
p.conn.Close()
if p.conn != nil {
p.conn.Close()
}
}
// Shutdown gracefully shuts down the peer by disconnecting it and waiting for
// all goroutines to finish.
func (p *peer) Shutdown() {
log.Tracef("[PEER] Shutdown peer %s", p.conn.RemoteAddr())
log.Tracef("[PEER] Shutdown peer %s", p.addr)
p.Disconnect()
p.wg.Wait()
}
// newPeer returns a new bitcoin peer for the provided server and connection.
// Use start to begin processing incoming and outgoing messages.
func newPeer(s *server, conn net.Conn, inbound bool, persistent bool) *peer {
func newPeer(s *server, conn net.Conn) *peer {
p := peer{
server: s,
protocolVersion: btcwire.ProtocolVersion,
btcnet: s.btcnet,
services: btcwire.SFNodeNetwork,
conn: conn,
addr: conn.RemoteAddr().String(),
timeConnected: time.Now(),
inbound: inbound,
inbound: true,
persistent: false,
knownAddresses: make(map[string]bool),
outputQueue: make(chan btcwire.Message, outputBufferSize),
quit: make(chan bool),
}
return &p
}
// newOutbountPeer returns a new bitcoin peer for the provided server and
// address and connects to it asynchronously. If the connetion is successful
// then the peer will also be started.
func newOutboundPeer(s *server, addr string, persistent bool) *peer {
p := peer{
server: s,
protocolVersion: btcwire.ProtocolVersion,
btcnet: s.btcnet,
services: btcwire.SFNodeNetwork,
addr: addr,
timeConnected: time.Now(),
inbound: false,
persistent: persistent,
knownAddresses: make(map[string]bool),
knownInventory: NewMruInventoryMap(maxKnownInventory),
@ -1079,5 +1127,82 @@ func newPeer(s *server, conn net.Conn, inbound bool, persistent bool) *peer {
blockProcessed: make(chan bool, 1),
quit: make(chan bool),
}
// set up p.na with a temporary address that we are connecting to with
// faked up service flags. We will replace this with the real one after
// version negotiation is successful. The only failure case here would
// be if the string was incomplete for connection so can't be split
// into address and port, and thus this would be invalid anyway. In
// which case we return nil to be handled by the caller.
// This must be done before we fork off the goroutine because as soon
// as this function returns the peer must have a valid netaddress.
ip, portStr, err := net.SplitHostPort(addr)
if err != nil {
log.Errorf("tried to create a new outbound peer with invalid "+
"address %s: %v", addr, err)
return nil
}
port, err := strconv.ParseUint(portStr, 10, 16)
if err != nil {
log.Errorf("tried to create a new outbound peer with invalid "+
"port %s: %v", portStr, err)
return nil
}
p.na = btcwire.NewNetAddressIPPort(net.ParseIP(ip), uint16(port), 0)
go func() {
// Select which dial method to call depending on whether or
// not a proxy is configured. Also, add proxy information to
// logged address if needed.
dial := net.Dial
faddr := addr
if cfg.Proxy != "" {
proxy := &socks.Proxy{cfg.Proxy, cfg.ProxyUser, cfg.ProxyPass}
dial = proxy.Dial
faddr = fmt.Sprintf("%s via proxy %s", addr, cfg.Proxy)
}
p.wg.Add(1)
// Attempt to connect to the peer. If the connection fails and
// this is a persistent connection, retry after the retry
// interval.
for !s.shutdown {
log.Debugf("[SRVR] Attempting to connect to %s", faddr)
conn, err := dial("tcp", addr)
if err != nil {
log.Errorf("[SRVR] failed to connect to %s: %v",
faddr, err)
if !persistent {
p.server.donePeers <- &p
p.wg.Done()
return
}
log.Infof("[SRVR] Retrying connection to %s "+
"in %s", faddr, connectionRetryInterval)
time.Sleep(connectionRetryInterval)
continue
}
// while we were sleeping trying to get connect then
// the server may have scheduled a shutdown. In that
// case we ditch the connection immediately.
if !s.shutdown {
p.server.addrManager.Attempt(p.na)
// Connection was successful so log it and start peer.
log.Infof("[SRVR] Connected to %s", conn.RemoteAddr())
p.conn = conn
p.Start()
} else {
p.server.donePeers <- &p
}
// We are done here, Start() will have grabbed
// additional waitgroup entries if we are not shutting
// down.
p.wg.Done()
return
}
}()
return &p
}

277
server.go
View file

@ -9,8 +9,8 @@ import (
"fmt"
"github.com/conformal/btcdb"
"github.com/conformal/btcwire"
"github.com/conformal/go-socks"
"net"
"strconv"
"sync"
"time"
)
@ -22,6 +22,9 @@ const supportedServices = btcwire.SFNodeNetwork
// when connecting to persistent peers.
const connectionRetryInterval = time.Second * 10
// defaultMaxOutbound is the default number of max outbound peers.
const defaultMaxOutbound = 8
// directionString is a helper function that returns a string that represents
// the direction of a connection (inbound or outbound).
func directionString(inbound bool) string {
@ -53,6 +56,7 @@ type server struct {
newPeers chan *peer
donePeers chan *peer
banPeers chan *peer
wakeup chan bool
relayInv chan *btcwire.InvVect
broadcast chan broadcastMsg
wg sync.WaitGroup
@ -62,29 +66,33 @@ type server struct {
// handleAddPeerMsg deals with adding new peers. It is invoked from the
// peerHandler goroutine.
func (s *server) handleAddPeerMsg(peers *list.List, banned map[string]time.Time, p *peer) {
func (s *server) handleAddPeerMsg(peers *list.List, banned map[string]time.Time, p *peer) bool {
if p == nil {
return false
}
// Ignore new peers if we're shutting down.
direction := directionString(p.inbound)
if s.shutdown {
log.Infof("[SRVR] New peer %s (%s) ignored - server is "+
"shutting down", p.conn.RemoteAddr(), direction)
"shutting down", p.addr, direction)
p.Shutdown()
return
return false
}
// Disconnect banned peers.
host, _, err := net.SplitHostPort(p.conn.RemoteAddr().String())
host, _, err := net.SplitHostPort(p.addr)
if err != nil {
log.Errorf("[SRVR] %v", err)
p.Shutdown()
return
return false
}
if banEnd, ok := banned[host]; ok {
if time.Now().Before(banEnd) {
log.Debugf("[SRVR] Peer %s is banned for another %v - "+
"disconnecting", host, banEnd.Sub(time.Now()))
p.Shutdown()
return
return false
}
log.Infof("[SRVR] Peer %s is no longer banned", host)
@ -96,43 +104,52 @@ func (s *server) handleAddPeerMsg(peers *list.List, banned map[string]time.Time,
// Limit max number of total peers.
if peers.Len() >= cfg.MaxPeers {
log.Infof("[SRVR] Max peers reached [%d] - disconnecting "+
"peer %s (%s)", cfg.MaxPeers, p.conn.RemoteAddr(),
direction)
"peer %s (%s)", cfg.MaxPeers, p.addr, direction)
p.Shutdown()
return
// TODO(oga) how to handle permanent peers here?
// they should be rescheduled.
return false
}
// Add the new peer and start it.
log.Infof("[SRVR] New peer %s (%s)", p.conn.RemoteAddr(), direction)
log.Infof("[SRVR] New peer %s (%s)", p.addr, direction)
peers.PushBack(p)
p.Start()
if p.inbound {
p.Start()
}
return true
}
// handleDonePeerMsg deals with peers that have signalled they are done. It is
// invoked from the peerHandler goroutine.
func (s *server) handleDonePeerMsg(peers *list.List, p *peer) {
func (s *server) handleDonePeerMsg(peers *list.List, p *peer) bool {
direction := directionString(p.inbound)
for e := peers.Front(); e != nil; e = e.Next() {
if e.Value == p {
peers.Remove(e)
log.Infof("[SRVR] Removed peer %s (%s)",
p.conn.RemoteAddr(), direction)
// Issue an asynchronous reconnect if the peer was a
// persistent outbound connection.
if !p.inbound && p.persistent {
addr := p.conn.RemoteAddr().String()
s.ConnectPeerAsync(addr, true)
if !p.inbound && p.persistent && !s.shutdown {
// attempt reconnect.
addr := p.addr
e.Value = newOutboundPeer(s, addr, true)
return false
}
return
peers.Remove(e)
log.Infof("[SRVR] Removed peer %s (%s)", p.addr,
direction)
return true
}
}
log.Warnf("[SRVR] Lost peer %v that we never had!", p)
return false
}
// handleBanPeerMsg deals with banning peers. It is invoked from the
// peerHandler goroutine.
func (s *server) handleBanPeerMsg(banned map[string]time.Time, p *peer) {
host, _, err := net.SplitHostPort(p.conn.RemoteAddr().String())
host, _, err := net.SplitHostPort(p.addr)
if err != nil {
log.Errorf("[SRVR] %v", err)
return
@ -172,8 +189,12 @@ func (s *server) handleBroadcastMsg(peers *list.List, bmsg *broadcastMsg) {
excluded = true
}
}
p := e.Value.(*peer)
// Don't broadcast to still connecting outbound peers .
if p.conn == nil {
excluded = true
}
if !excluded {
p := e.Value.(*peer)
p.QueueMessage(bmsg.message)
}
}
@ -192,7 +213,7 @@ func (s *server) listenHandler(listener net.Listener) {
}
continue
}
s.AddPeer(newPeer(s, conn, true, false))
s.AddPeer(newPeer(s, conn))
}
s.wg.Done()
log.Tracef("[SRVR] Listener handler done for %s", listener.Addr())
@ -213,17 +234,80 @@ func (s *server) peerHandler() {
log.Tracef("[SRVR] Starting peer handler")
peers := list.New()
bannedPeers := make(map[string]time.Time)
outboundPeers := 0
maxOutbound := defaultMaxOutbound
if cfg.MaxPeers < maxOutbound {
maxOutbound = cfg.MaxPeers
}
var wakeupTimer *time.Timer = nil
// Do initial DNS seeding to populate address manager.
if !cfg.DisableDNSSeed {
proxy := ""
if cfg.Proxy != "" && cfg.UseTor {
proxy = cfg.Proxy
}
for _, seeder := range activeNetParams.dnsSeeds {
seedpeers := dnsDiscover(seeder, proxy)
if len(seedpeers) == 0 {
continue
}
addresses := make([]*btcwire.NetAddress, len(seedpeers))
// if this errors then we have *real* problems
intPort, _ := strconv.Atoi(activeNetParams.peerPort)
for i, peer := range seedpeers {
addresses[i] = new(btcwire.NetAddress)
addresses[i].SetAddress(peer, uint16(intPort))
// bitcoind seeds with addresses from
// a time randomly selected between 3
// and 7 days ago.
addresses[i].Timestamp = time.Now().Add(-1 *
time.Second * time.Duration(secondsIn3Days+
s.addrManager.rand.Int31n(secondsIn4Days)))
}
// Bitcoind uses a lookup of the dns seeder here. This
// is rather strange since the values looked up by the
// DNS seed lookups will vary quite a lot.
// to replicate this behaviour we put all addresses as
// having come from the first one.
s.addrManager.AddAddresses(addresses, addresses[0])
}
// XXX if this is empty do we want to use hardcoded
// XXX peers like bitcoind does?
}
// Start up persistent peers.
permanentPeers := cfg.ConnectPeers
if len(permanentPeers) == 0 {
permanentPeers = cfg.AddPeers
}
for _, addr := range permanentPeers {
if s.handleAddPeerMsg(peers, bannedPeers,
newOutboundPeer(s, addr, true)) {
outboundPeers++
}
}
// if nothing else happens, wake us up soon.
time.AfterFunc(10*time.Second, func() { s.wakeup <- true })
// Live while we're not shutting down or there are still connected peers.
for !s.shutdown || peers.Len() != 0 {
select {
// New peers connected to the server.
case p := <-s.newPeers:
s.handleAddPeerMsg(peers, bannedPeers, p)
if s.handleAddPeerMsg(peers, bannedPeers, p) &&
!p.inbound {
outboundPeers++
}
// Disconnected peers.
case p := <-s.donePeers:
s.handleDonePeerMsg(peers, p)
// handleDonePeerMsg return true if it removed a peer
if s.handleDonePeerMsg(peers, p) {
outboundPeers--
}
// Peer to ban.
case p := <-s.banPeers:
@ -238,6 +322,10 @@ func (s *server) peerHandler() {
case bmsg := <-s.broadcast:
s.handleBroadcastMsg(peers, &bmsg)
// Used by timers below to wake us back up.
case <-s.wakeup:
// this page left intentionally blank
// Shutdown the peer handler.
case <-s.quit:
// Shutdown peers.
@ -246,6 +334,98 @@ func (s *server) peerHandler() {
p.Shutdown()
}
}
// Timer was just to make sure we woke up again soon. so cancel
// and remove it as soon as we next come around.
if wakeupTimer != nil {
wakeupTimer.Stop()
wakeupTimer = nil
}
// Only try connect to more peers if we actually need more
if outboundPeers >= maxOutbound || s.shutdown {
continue
}
groups := make(map[string]int)
for e := peers.Front(); e != nil; e = e.Next() {
peer := e.Value.(*peer)
if !peer.inbound {
groups[GroupKey(peer.na)]++
}
}
tries := 0
for outboundPeers < maxOutbound &&
peers.Len() < cfg.MaxPeers && !s.shutdown {
// We bias like bitcoind does, 10 for no outgoing
// up to 90 (8) for the selection of new vs tried
//addresses.
nPeers := outboundPeers
if nPeers > 8 {
nPeers = 8
}
addr := s.addrManager.GetAddress("any", 10+nPeers*10)
if addr == nil {
break
}
key := GroupKey(addr.na)
// Address will not be invalid, local or unroutable
// because addrmanager rejects those on addition.
// Just check that we don't already have an address
// in the same group so that we are not connecting
// to the same network segment at the expense of
// others. bitcoind breaks out of the loop here, but
// we continue to try other addresses.
if groups[key] != 0 {
continue
}
tries++
// After 100 bad tries exit the loop and we'll try again
// later.
if tries > 100 {
break
}
// XXX if we have limited that address skip
// only allow recent nodes (10mins) after we failed 30
// times
if time.Now().After(addr.lastattempt.Add(10*time.Minute)) &&
tries < 30 {
continue
}
// allow nondefault ports after 50 failed tries.
if fmt.Sprintf("%d", addr.na.Port) !=
activeNetParams.peerPort && tries < 50 {
continue
}
addrStr := NetAddressKey(addr.na)
tries = 0
// any failure will be due to banned peers etc. we have
// already checked that we have room for more peers.
if s.handleAddPeerMsg(peers, bannedPeers,
newOutboundPeer(s, addrStr, false)) {
outboundPeers++
groups[key]++
}
}
// We we need more peers, wake up in ten seconds and try again.
if outboundPeers < maxOutbound && peers.Len() < cfg.MaxPeers {
time.AfterFunc(10*time.Second, func() {
s.wakeup <- true
})
}
}
if wakeupTimer != nil {
wakeupTimer.Stop()
wakeupTimer = nil
}
s.blockManager.Stop()
@ -279,52 +459,6 @@ func (s *server) BroadcastMessage(msg btcwire.Message, exclPeers ...*peer) {
s.broadcast <- bmsg
}
// ConnectPeerAsync attempts to asynchronously connect to addr. If successful,
// a new peer is created and added to the server's peer list.
func (s *server) ConnectPeerAsync(addr string, persistent bool) {
// Don't try to connect to a peer if the server is shutting down.
if s.shutdown {
return
}
go func() {
// Select which dial method to call depending on whether or
// not a proxy is configured. Also, add proxy information to
// logged address if needed.
dial := net.Dial
faddr := addr
if cfg.Proxy != "" {
proxy := &socks.Proxy{cfg.Proxy, cfg.ProxyUser, cfg.ProxyPass}
dial = proxy.Dial
faddr = fmt.Sprintf("%s via proxy %s", addr, cfg.Proxy)
}
// Attempt to connect to the peer. If the connection fails and
// this is a persistent connection, retry after the retry
// interval.
for !s.shutdown {
log.Debugf("[SRVR] Attempting to connect to %s", faddr)
conn, err := dial("tcp", addr)
if err != nil {
log.Errorf("[SRVR] %v", err)
if !persistent {
return
}
log.Infof("[SRVR] Retrying connection to %s "+
"in %s", faddr, connectionRetryInterval)
time.Sleep(connectionRetryInterval)
continue
}
// Connection was successful so log it and create a new
// peer.
log.Infof("[SRVR] Connected to %s", conn.RemoteAddr())
s.AddPeer(newPeer(s, conn, false, persistent))
return
}
}()
}
// Start begins accepting connections from peers.
func (s *server) Start() {
// Already started?
@ -465,6 +599,7 @@ func newServer(addr string, db btcdb.Db, btcnet btcwire.BitcoinNet) (*server, er
newPeers: make(chan *peer, cfg.MaxPeers),
donePeers: make(chan *peer, cfg.MaxPeers),
banPeers: make(chan *peer, cfg.MaxPeers),
wakeup: make(chan bool),
relayInv: make(chan *btcwire.InvVect, cfg.MaxPeers),
broadcast: make(chan broadcastMsg, cfg.MaxPeers),
quit: make(chan bool),