@ -62,7 +62,7 @@ type KadParams struct {
RetryExponent int // exponent to multiply retry intervals with
RetryExponent int // exponent to multiply retry intervals with
MaxRetries int // maximum number of redial attempts
MaxRetries int // maximum number of redial attempts
// function to sanction or prevent suggesting a peer
// function to sanction or prevent suggesting a peer
Reachable func ( Overlay Addr) bool Reachable func ( * Bzz Addr) bool
} }
// NewKadParams returns a params struct with default values
// NewKadParams returns a params struct with default values
@ -106,45 +106,22 @@ func NewKademlia(addr []byte, params *KadParams) *Kademlia {
} }
} }
// OverlayPeer interface captures the common aspect of view of a peer from the Overlay
// entry represents a Kademlia table entry (an extension of BzzAddr)
// topology driver
type OverlayPeer interface {
Address ( ) [ ] byte
}
// OverlayConn represents a connected peer
type OverlayConn interface {
OverlayPeer
Drop ( error ) // call to indicate a peer should be expunged
Off ( ) OverlayAddr // call to return a persitent OverlayAddr
}
// OverlayAddr represents a kademlia peer record
type OverlayAddr interface {
OverlayPeer
Update ( OverlayAddr ) OverlayAddr // returns the updated version of the original
}
// entry represents a Kademlia table entry (an extension of OverlayPeer)
type entry struct { type entry struct {
OverlayPeer * BzzAddr
conn * Peer
seenAt time . Time seenAt time . Time
retries int retries int
} }
// newEntry creates a kademlia peer from an OverlayPeer interface
// newEntry creates a kademlia peer from a *Peer
func newEntry ( p OverlayPee r) * entry { func newEntry ( p * BzzAddr ) * entry {
return & entry { return & entry {
OverlayPee r: p , BzzAddr : p ,
seenAt : time . Now ( ) , seenAt : time . Now ( ) ,
} }
} }
// Bin is the binary (bitvector) serialisation of the entry address
func ( e * entry ) Bin ( ) string {
return pot . ToBin ( e . addr ( ) . Address ( ) )
}
// Label is a short tag for the entry for debug
// Label is a short tag for the entry for debug
func Label ( e * entry ) string { func Label ( e * entry ) string {
return fmt . Sprintf ( "%s (%d)" , e . Hex ( ) [ : 4 ] , e . retries ) return fmt . Sprintf ( "%s (%d)" , e . Hex ( ) [ : 4 ] , e . retries )
@ -152,29 +129,12 @@ func Label(e *entry) string {
// Hex is the hexadecimal serialisation of the entry address
// Hex is the hexadecimal serialisation of the entry address
func ( e * entry ) Hex ( ) string { func ( e * entry ) Hex ( ) string {
return fmt . Sprintf ( "%x" , e . addr ( ) . Address ( ) ) return fmt . Sprintf ( "%x" , e . Address ( ) )
} }
// String is the short tag for the entry
// Register enters each address as kademlia peer record into the
func ( e * entry ) String ( ) string {
return fmt . Sprintf ( "%s (%d)" , e . Hex ( ) [ : 8 ] , e . retries )
}
// addr returns the kad peer record (OverlayAddr) corresponding to the entry
func ( e * entry ) addr ( ) OverlayAddr {
a , _ := e . OverlayPeer . ( OverlayAddr )
return a
}
// conn returns the connected peer (OverlayPeer) corresponding to the entry
func ( e * entry ) conn ( ) OverlayConn {
c , _ := e . OverlayPeer . ( OverlayConn )
return c
}
// Register enters each OverlayAddr as kademlia peer record into the
// database of known peer addresses
// database of known peer addresses
func ( k * Kademlia ) Register ( peers [ ] Overlay Addr) error { func ( k * Kademlia ) Register ( peers ... * BzzAddr ) error {
k . lock . Lock ( ) k . lock . Lock ( )
defer k . lock . Unlock ( ) defer k . lock . Unlock ( )
var known , size int var known , size int
@ -203,7 +163,6 @@ func (k *Kademlia) Register(peers []OverlayAddr) error {
if k . addrCountC != nil && size - known > 0 { if k . addrCountC != nil && size - known > 0 {
k . addrCountC <- k . addrs . Size ( ) k . addrCountC <- k . addrs . Size ( )
} }
// log.Trace(fmt.Sprintf("%x registered %v peers, %v known, total: %v", k.BaseAddr()[:4], size, known, k.addrs.Size()))
k . sendNeighbourhoodDepthChange ( ) k . sendNeighbourhoodDepthChange ( )
return nil return nil
@ -212,7 +171,7 @@ func (k *Kademlia) Register(peers []OverlayAddr) error {
// SuggestPeer returns a known peer for the lowest proximity bin for the
// SuggestPeer returns a known peer for the lowest proximity bin for the
// lowest bincount below depth
// lowest bincount below depth
// naturally if there is an empty row it returns a peer for that
// naturally if there is an empty row it returns a peer for that
func ( k * Kademlia ) SuggestPeer ( ) ( a Overlay Addr, o int , want bool ) { func ( k * Kademlia ) SuggestPeer ( ) ( a * Bzz Addr, o int , want bool ) {
k . lock . Lock ( ) k . lock . Lock ( )
defer k . lock . Unlock ( ) defer k . lock . Unlock ( )
minsize := k . MinBinSize minsize := k . MinBinSize
@ -224,15 +183,18 @@ func (k *Kademlia) SuggestPeer() (a OverlayAddr, o int, want bool) {
if po < depth { if po < depth {
return false return false
} }
a = k . callable ( val ) e := val . ( * entry )
c := k . callable ( e )
if c {
a = e . BzzAddr
}
ppo = po ppo = po
return a == nil return ! c
} ) } )
if a != nil { if a != nil {
log . Trace ( fmt . Sprintf ( "%08x candidate nearest neighbour found: %v (%v)" , k . BaseAddr ( ) [ : 4 ] , a , ppo ) ) log . Trace ( fmt . Sprintf ( "%08x candidate nearest neighbour found: %v (%v)" , k . BaseAddr ( ) [ : 4 ] , a , ppo ) )
return a , 0 , false return a , 0 , false
} }
// log.Trace(fmt.Sprintf("%08x no candidate nearest neighbours to connect to (Depth: %v, minProxSize: %v) %#v", k.BaseAddr()[:4], depth, k.MinProxBinSize, a))
var bpo [ ] int var bpo [ ] int
prev := - 1 prev := - 1
@ -250,7 +212,6 @@ func (k *Kademlia) SuggestPeer() (a OverlayAddr, o int, want bool) {
} ) } )
// all buckets are full, ie., minsize == k.MinBinSize
// all buckets are full, ie., minsize == k.MinBinSize
if len ( bpo ) == 0 { if len ( bpo ) == 0 {
// log.Debug(fmt.Sprintf("%08x: all bins saturated", k.BaseAddr()[:4]))
return nil , 0 , false return nil , 0 , false
} }
// as long as we got candidate peers to connect to
// as long as we got candidate peers to connect to
@ -264,8 +225,12 @@ func (k *Kademlia) SuggestPeer() (a OverlayAddr, o int, want bool) {
return false return false
} }
return f ( func ( val pot . Val , _ int ) bool { return f ( func ( val pot . Val , _ int ) bool {
a = k . callable ( val ) e := val . ( * entry )
return a == nil c := k . callable ( e )
if c {
a = e . BzzAddr
}
return ! c
} ) } )
} ) } )
// found a candidate
// found a candidate
@ -282,25 +247,26 @@ func (k *Kademlia) SuggestPeer() (a OverlayAddr, o int, want bool) {
} }
// On inserts the peer as a kademlia peer into the live peers
// On inserts the peer as a kademlia peer into the live peers
func ( k * Kademlia ) On ( p OverlayConn ) ( uint8 , bool ) { func ( k * Kademlia ) On ( p * Peer ) ( uint8 , bool ) {
k . lock . Lock ( ) k . lock . Lock ( )
defer k . lock . Unlock ( ) defer k . lock . Unlock ( )
e := newEntry ( p )
var ins bool var ins bool
k . conns , _ , _ , _ = pot . Swap ( k . conns , p , pof , func ( v pot . Val ) pot . Val { k . conns , _ , _ , _ = pot . Swap ( k . conns , p , pof , func ( v pot . Val ) pot . Val {
// if not found live
// if not found live
if v == nil { if v == nil {
ins = true ins = true
// insert new online peer into conns
// insert new online peer into conns
return e return p
} }
// found among live peers, do nothing
// found among live peers, do nothing
return v return v
} ) } )
if ins { if ins {
a := newEntry ( p . BzzAddr )
a . conn = p
// insert new online peer into addrs
// insert new online peer into addrs
k . addrs , _ , _ , _ = pot . Swap ( k . addrs , p , pof , func ( v pot . Val ) pot . Val { k . addrs , _ , _ , _ = pot . Swap ( k . addrs , p , pof , func ( v pot . Val ) pot . Val {
return e return a
} ) } )
// send new address count value only if the peer is inserted
// send new address count value only if the peer is inserted
if k . addrCountC != nil { if k . addrCountC != nil {
@ -324,6 +290,8 @@ func (k *Kademlia) On(p OverlayConn) (uint8, bool) {
// Not receiving from the returned channel will block On function
// Not receiving from the returned channel will block On function
// when the neighbourhood depth is changed.
// when the neighbourhood depth is changed.
func ( k * Kademlia ) NeighbourhoodDepthC ( ) <- chan int { func ( k * Kademlia ) NeighbourhoodDepthC ( ) <- chan int {
k . lock . Lock ( )
defer k . lock . Unlock ( )
if k . nDepthC == nil { if k . nDepthC == nil {
k . nDepthC = make ( chan int ) k . nDepthC = make ( chan int )
} }
@ -357,7 +325,7 @@ func (k *Kademlia) AddrCountC() <-chan int {
} }
// Off removes a peer from among live peers
// Off removes a peer from among live peers
func ( k * Kademlia ) Off ( p OverlayConn ) { func ( k * Kademlia ) Off ( p * Peer ) {
k . lock . Lock ( ) k . lock . Lock ( )
defer k . lock . Unlock ( ) defer k . lock . Unlock ( )
var del bool var del bool
@ -367,7 +335,7 @@ func (k *Kademlia) Off(p OverlayConn) {
panic ( fmt . Sprintf ( "connected peer not found %v" , p ) ) panic ( fmt . Sprintf ( "connected peer not found %v" , p ) )
} }
del = true del = true
return newEntry ( p . Off ( ) ) return newEntry ( p . BzzAddr )
} ) } )
if del { if del {
@ -383,7 +351,7 @@ func (k *Kademlia) Off(p OverlayConn) {
} }
} }
func ( k * Kademlia ) EachBin ( base [ ] byte , pof pot . Pof , o int , eachBinFunc func ( conn OverlayConn , po int ) bool ) { func ( k * Kademlia ) EachBin ( base [ ] byte , pof pot . Pof , o int , eachBinFunc func ( conn * Peer , po int ) bool ) {
k . lock . RLock ( ) k . lock . RLock ( )
defer k . lock . RUnlock ( ) defer k . lock . RUnlock ( )
@ -403,7 +371,7 @@ func (k *Kademlia) EachBin(base []byte, pof pot.Pof, o int, eachBinFunc func(con
for bin := startPo ; bin <= endPo ; bin ++ { for bin := startPo ; bin <= endPo ; bin ++ {
f ( func ( val pot . Val , _ int ) bool { f ( func ( val pot . Val , _ int ) bool {
return eachBinFunc ( val . ( * entry ) . conn ( ) , bin ) return eachBinFunc ( val . ( * Peer ) , bin )
} ) } )
} }
return true return true
@ -413,13 +381,13 @@ func (k *Kademlia) EachBin(base []byte, pof pot.Pof, o int, eachBinFunc func(con
// EachConn is an iterator with args (base, po, f) applies f to each live peer
// EachConn is an iterator with args (base, po, f) applies f to each live peer
// that has proximity order po or less as measured from the base
// that has proximity order po or less as measured from the base
// if base is nil, kademlia base address is used
// if base is nil, kademlia base address is used
func ( k * Kademlia ) EachConn ( base [ ] byte , o int , f func ( OverlayConn , int , bool ) bool ) { func ( k * Kademlia ) EachConn ( base [ ] byte , o int , f func ( * Peer , int , bool ) bool ) {
k . lock . RLock ( ) k . lock . RLock ( )
defer k . lock . RUnlock ( ) defer k . lock . RUnlock ( )
k . eachConn ( base , o , f ) k . eachConn ( base , o , f )
} }
func ( k * Kademlia ) eachConn ( base [ ] byte , o int , f func ( OverlayConn , int , bool ) bool ) { func ( k * Kademlia ) eachConn ( base [ ] byte , o int , f func ( * Peer , int , bool ) bool ) {
if len ( base ) == 0 { if len ( base ) == 0 {
base = k . base base = k . base
} }
@ -428,20 +396,20 @@ func (k *Kademlia) eachConn(base []byte, o int, f func(OverlayConn, int, bool) b
if po > o { if po > o {
return true return true
} }
return f ( val . ( * entry ) . conn ( ) , po , po >= depth ) return f ( val . ( * Peer ) , po , po >= depth )
} ) } )
} }
// EachAddr called with (base, po, f) is an iterator applying f to each known peer
// EachAddr called with (base, po, f) is an iterator applying f to each known peer
// that has proximity order po or less as measured from the base
// that has proximity order po or less as measured from the base
// if base is nil, kademlia base address is used
// if base is nil, kademlia base address is used
func ( k * Kademlia ) EachAddr ( base [ ] byte , o int , f func ( Overlay Addr, int , bool ) bool ) { func ( k * Kademlia ) EachAddr ( base [ ] byte , o int , f func ( * Bzz Addr, int , bool ) bool ) {
k . lock . RLock ( ) k . lock . RLock ( )
defer k . lock . RUnlock ( ) defer k . lock . RUnlock ( )
k . eachAddr ( base , o , f ) k . eachAddr ( base , o , f )
} }
func ( k * Kademlia ) eachAddr ( base [ ] byte , o int , f func ( Overlay Addr, int , bool ) bool ) { func ( k * Kademlia ) eachAddr ( base [ ] byte , o int , f func ( * Bzz Addr, int , bool ) bool ) {
if len ( base ) == 0 { if len ( base ) == 0 {
base = k . base base = k . base
} }
@ -450,7 +418,7 @@ func (k *Kademlia) eachAddr(base []byte, o int, f func(OverlayAddr, int, bool) b
if po > o { if po > o {
return true return true
} }
return f ( val . ( * entry ) . addr ( ) , po , po >= depth ) return f ( val . ( * entry ) . BzzAddr , po , po >= depth )
} ) } )
} }
@ -472,12 +440,11 @@ func (k *Kademlia) neighbourhoodDepth() (depth int) {
return depth return depth
} }
// callable when called with val,
// callable decides if an address entry represents a callable peer
func ( k * Kademlia ) callable ( val pot . Val ) OverlayAddr { func ( k * Kademlia ) callable ( e * entry ) bool {
e := val . ( * entry )
// not callable if peer is live or exceeded maxRetries
// not callable if peer is live or exceeded maxRetries
if e . conn ( ) != nil || e . retries > k . MaxRetries { if e . conn != nil || e . retries > k . MaxRetries {
return nil return false
} }
// calculate the allowed number of retries based on time lapsed since last seen
// calculate the allowed number of retries based on time lapsed since last seen
timeAgo := int64 ( time . Since ( e . seenAt ) ) timeAgo := int64 ( time . Since ( e . seenAt ) )
@ -491,17 +458,17 @@ func (k *Kademlia) callable(val pot.Val) OverlayAddr {
// peer can be retried again
// peer can be retried again
if retries < e . retries { if retries < e . retries {
log . Trace ( fmt . Sprintf ( "%08x: %v long time since last try (at %v) needed before retry %v, wait only warrants %v" , k . BaseAddr ( ) [ : 4 ] , e , timeAgo , e . retries , retries ) ) log . Trace ( fmt . Sprintf ( "%08x: %v long time since last try (at %v) needed before retry %v, wait only warrants %v" , k . BaseAddr ( ) [ : 4 ] , e , timeAgo , e . retries , retries ) )
return nil return false
} }
// function to sanction or prevent suggesting a peer
// function to sanction or prevent suggesting a peer
if k . Reachable != nil && ! k . Reachable ( e . addr ( ) ) { if k . Reachable != nil && ! k . Reachable ( e . BzzAddr ) {
log . Trace ( fmt . Sprintf ( "%08x: peer %v is temporarily not callable" , k . BaseAddr ( ) [ : 4 ] , e ) ) log . Trace ( fmt . Sprintf ( "%08x: peer %v is temporarily not callable" , k . BaseAddr ( ) [ : 4 ] , e ) )
return nil return false
} }
e . retries ++ e . retries ++
log . Trace ( fmt . Sprintf ( "%08x: peer %v is callable" , k . BaseAddr ( ) [ : 4 ] , e ) ) log . Trace ( fmt . Sprintf ( "%08x: peer %v is callable" , k . BaseAddr ( ) [ : 4 ] , e ) )
return e . addr ( ) return true
} }
// BaseAddr return the kademlia base address
// BaseAddr return the kademlia base address
@ -516,7 +483,8 @@ func (k *Kademlia) String() string {
return k . string ( ) return k . string ( )
} }
// String returns kademlia table + kaddb table displayed with ascii
// string returns kademlia table + kaddb table displayed with ascii
// caller must hold the lock
func ( k * Kademlia ) string ( ) string { func ( k * Kademlia ) string ( ) string {
wsrow := " " wsrow := " "
var rows [ ] string var rows [ ] string
@ -538,7 +506,7 @@ func (k *Kademlia) string() string {
row := [ ] string { fmt . Sprintf ( "%2d" , size ) } row := [ ] string { fmt . Sprintf ( "%2d" , size ) }
rest -= size rest -= size
f ( func ( val pot . Val , vpo int ) bool { f ( func ( val pot . Val , vpo int ) bool {
e := val . ( * ent ry ) e := val . ( * Pe er)
row = append ( row , fmt . Sprintf ( "%x" , e . Address ( ) [ : 2 ] ) ) row = append ( row , fmt . Sprintf ( "%x" , e . Address ( ) [ : 2 ] ) )
rowlen ++ rowlen ++
return rowlen < 4 return rowlen < 4
@ -594,8 +562,9 @@ type PeerPot struct {
EmptyBins [ ] int EmptyBins [ ] int
} }
// NewPeerPotMap creates a map of pot record of Overlay Addr with keys
// NewPeerPotMap creates a map of pot record of *Bzz Addr with keys
// as hexadecimal representations of the address.
// as hexadecimal representations of the address.
// used for testing only
func NewPeerPotMap ( kadMinProxSize int , addrs [ ] [ ] byte ) map [ string ] * PeerPot { func NewPeerPotMap ( kadMinProxSize int , addrs [ ] [ ] byte ) map [ string ] * PeerPot {
// create a table of all nodes for health check
// create a table of all nodes for health check
np := pot . NewPot ( nil , 0 ) np := pot . NewPot ( nil , 0 )
@ -640,6 +609,7 @@ func NewPeerPotMap(kadMinProxSize int, addrs [][]byte) map[string]*PeerPot {
// saturation returns the lowest proximity order that the bin for that order
// saturation returns the lowest proximity order that the bin for that order
// has less than n peers
// has less than n peers
// It is used in Healthy function for testing only
func ( k * Kademlia ) saturation ( n int ) int { func ( k * Kademlia ) saturation ( n int ) int {
prev := - 1 prev := - 1
k . addrs . EachBin ( k . base , pof , 0 , func ( po , size int , f func ( func ( val pot . Val , i int ) bool ) bool ) bool { k . addrs . EachBin ( k . base , pof , 0 , func ( po , size int , f func ( func ( val pot . Val , i int ) bool ) bool ) bool {
@ -654,7 +624,7 @@ func (k *Kademlia) saturation(n int) int {
} }
// full returns true if all required bins have connected peers.
// full returns true if all required bins have connected peers.
// It is used in Healthy function.
// It is used in Healthy function for testing only
func ( k * Kademlia ) full ( emptyBins [ ] int ) ( full bool ) { func ( k * Kademlia ) full ( emptyBins [ ] int ) ( full bool ) {
prev := 0 prev := 0
e := len ( emptyBins ) e := len ( emptyBins )
@ -688,10 +658,13 @@ func (k *Kademlia) full(emptyBins []int) (full bool) {
return e == 0 return e == 0
} }
// knowNearestNeighbours tests if all known nearest neighbours given as arguments
// are found in the addressbook
// It is used in Healthy function for testing only
func ( k * Kademlia ) knowNearestNeighbours ( peers [ ] [ ] byte ) bool { func ( k * Kademlia ) knowNearestNeighbours ( peers [ ] [ ] byte ) bool {
pm := make ( map [ string ] bool ) pm := make ( map [ string ] bool )
k . eachAddr ( nil , 255 , func ( p Overlay Addr, po int , nn bool ) bool { k . eachAddr ( nil , 255 , func ( p * Bzz Addr, po int , nn bool ) bool {
if ! nn { if ! nn {
return false return false
} }
@ -709,10 +682,13 @@ func (k *Kademlia) knowNearestNeighbours(peers [][]byte) bool {
return true return true
} }
// gotNearestNeighbours tests if all known nearest neighbours given as arguments
// are connected peers
// It is used in Healthy function for testing only
func ( k * Kademlia ) gotNearestNeighbours ( peers [ ] [ ] byte ) ( got bool , n int , missing [ ] [ ] byte ) { func ( k * Kademlia ) gotNearestNeighbours ( peers [ ] [ ] byte ) ( got bool , n int , missing [ ] [ ] byte ) {
pm := make ( map [ string ] bool ) pm := make ( map [ string ] bool )
k . eachConn ( nil , 255 , func ( p OverlayConn , po int , nn bool ) bool { k . eachConn ( nil , 255 , func ( p * Peer , po int , nn bool ) bool {
if ! nn { if ! nn {
return false return false
} }
@ -735,6 +711,7 @@ func (k *Kademlia) gotNearestNeighbours(peers [][]byte) (got bool, n int, missin
} }
// Health state of the Kademlia
// Health state of the Kademlia
// used for testing only
type Health struct { type Health struct {
KnowNN bool // whether node knows all its nearest neighbours
KnowNN bool // whether node knows all its nearest neighbours
GotNN bool // whether node is connected to all its nearest neighbours
GotNN bool // whether node is connected to all its nearest neighbours
@ -746,6 +723,7 @@ type Health struct {
// Healthy reports the health state of the kademlia connectivity
// Healthy reports the health state of the kademlia connectivity
// returns a Health struct
// returns a Health struct
// used for testing only
func ( k * Kademlia ) Healthy ( pp * PeerPot ) * Health { func ( k * Kademlia ) Healthy ( pp * PeerPot ) * Health {
k . lock . RLock ( ) k . lock . RLock ( )
defer k . lock . RUnlock ( ) defer k . lock . RUnlock ( )
Viktor Trón
6 years ago
committed by
Balint Gabor