update spec and addrbook.go

docs/specification/new-spec/p2p/node.md

@@ -12,7 +12,7 @@ Seeds should operate full nodes with the PEX reactor in a "crawler" mode
 that continuously explores to validate the availability of peers.
 
 Seeds should only respond with some top percentile of the best peers it knows about.
-See [reputation](TODO) for details on peer quality.
+See [the peer-exchange docs](/docs/specification/new-spec/reactors/pex/pex.md)for details on peer quality.
 
 ## New Full Node
 

docs/specification/new-spec/p2p/peer.md

@@ -2,24 +2,23 @@
 
 This document explains how Tendermint Peers are identified and how they connect to one another.
 
-For details on peer discovery, see the [peer exchange (PEX) reactor doc](pex.md).
+For details on peer discovery, see the [peer exchange (PEX) reactor doc](/docs/specification/new-spec/reactors/pex/pex.md).
 
 ## Peer Identity
 
 Tendermint peers are expected to maintain long-term persistent identities in the form of a public key.
 Each peer has an ID defined as `peer.ID == peer.PubKey.Address()`, where `Address` uses the scheme defined in go-crypto.
 
-A single peer ID can have multiple IP addresses associated with it.
-TODO: define how to deal with this.
+A single peer ID can have multiple IP addresses associated with it, but a node
+will only ever connect to one at a time.
 
 When attempting to connect to a peer, we use the PeerURL: `<ID>@<IP>:<PORT>`.
 We will attempt to connect to the peer at IP:PORT, and verify,
 via authenticated encryption, that it is in possession of the private key
 corresponding to `<ID>`. This prevents man-in-the-middle attacks on the peer layer.
 
-Peers can also be connected to without specifying an ID, ie. just `<IP>:<PORT>`.
-In this case, the peer must be authenticated out-of-band of Tendermint,
-for instance via VPN.
+If `auth_enc = false`, peers can use an arbitrary ID, but they must always use
+one. Authentication can then happen out-of-band of Tendermint, for instance via VPN.
 
 ## Connections
 
@@ -84,12 +83,13 @@ The Tendermint Version Handshake allows the peers to exchange their NodeInfo:
 ```golang
 type NodeInfo struct {
   ID         p2p.ID
-  Moniker    string
-  Network    string
-  RemoteAddr string
   ListenAddr string
+
+  Network    string
   Version    string
   Channels   []int8
+
+  Moniker    string
   Other      []string
 }
 ```
@@ -98,9 +98,10 @@ The connection is disconnected if:
 - `peer.NodeInfo.ID` is not equal `peerConn.ID`
 - `peer.NodeInfo.Version` is not formatted as `X.X.X` where X are integers known as Major, Minor, and Revision
 - `peer.NodeInfo.Version` Major is not the same as ours
-- `peer.NodeInfo.Version` Minor is not the same as ours
 - `peer.NodeInfo.Network` is not the same as ours
 - `peer.Channels` does not intersect with our known Channels.
+- `peer.NodeInfo.ListenAddr` is malformed or is a DNS host that cannot be
+  resolved
 
 
 At this point, if we have not disconnected, the peer is valid.

docs/specification/new-spec/reactors/pex/pex.md

@@ -31,8 +31,9 @@ we try the seeds again.
 
 ## Listening
 
-Peers listen on a configurable ListenAddr that they self-report during
-handshakes with other peers.
+Peers listen on a configurable ListenAddr that they self-report in their
+NodeInfo during handshakes with other peers. Peers accept up to (MaxNumPeers -
+MinNumOutboundPeers) incoming peers.
 
 
 ## Address Book

p2p/pex/addrbook.go

@@ -493,11 +493,11 @@ func (a *addrBook) getBucket(bucketType byte, bucketIdx int) map[string]*knownAd
 
 // Adds ka to new bucket. Returns false if it couldn't do it cuz buckets full.
 // NOTE: currently it always returns true.
-func (a *addrBook) addToNewBucket(ka *knownAddress, bucketIdx int) bool {
+func (a *addrBook) addToNewBucket(ka *knownAddress, bucketIdx int) {
 	// Sanity check
 	if ka.isOld() {
-		a.Logger.Error(cmn.Fmt("Cannot add address already in old bucket to a new bucket: %v", ka))
-		return false
+		a.Logger.Error("Failed Sanity Check! Cant add old address to new bucket", "ka", knownAddress, "bucket", bucketIdx)
+		return
 	}
 
 	addrStr := ka.Addr.String()
@@ -505,7 +505,7 @@ func (a *addrBook) addToNewBucket(ka *knownAddress, bucketIdx int) bool {
 
 	// Already exists?
 	if _, ok := bucket[addrStr]; ok {
-		return true
+		return
 	}
 
 	// Enforce max addresses.
@@ -523,8 +523,6 @@ func (a *addrBook) addToNewBucket(ka *knownAddress, bucketIdx int) bool {
 
 	// Add it to addrLookup
 	a.addrLookup[ka.ID()] = ka
-
-	return true
 }
 
 // Adds ka to old bucket. Returns false if it couldn't do it cuz buckets full.
@@ -627,7 +625,6 @@ func (a *addrBook) addAddress(addr, src *p2p.NetAddress) error {
 	}
 
 	ka := a.addrLookup[addr.ID]
-
 	if ka != nil {
 		// Already old.
 		if ka.isOld() {
@@ -647,10 +644,7 @@ func (a *addrBook) addAddress(addr, src *p2p.NetAddress) error {
 	}
 
 	bucket := a.calcNewBucket(addr, src)
-	added := a.addToNewBucket(ka, bucket)
-	if !added {
-		return ErrAddrBookFull{addr, a.size()}
-	}
+	a.addToNewBucket(ka, bucket)
 	return nil
 }
 
@@ -696,20 +690,13 @@ func (a *addrBook) moveToOld(ka *knownAddress) {
 	oldBucketIdx := a.calcOldBucket(ka.Addr)
 	added := a.addToOldBucket(ka, oldBucketIdx)
 	if !added {
-		// No room, must evict something
+		// No room; move the oldest to a new bucket
 		oldest := a.pickOldest(bucketTypeOld, oldBucketIdx)
 		a.removeFromBucket(oldest, bucketTypeOld, oldBucketIdx)
-		// Find new bucket to put oldest in
 		newBucketIdx := a.calcNewBucket(oldest.Addr, oldest.Src)
-		added := a.addToNewBucket(oldest, newBucketIdx)
-		// No space in newBucket either, just put it in freedBucket from above.
-		if !added {
-			added := a.addToNewBucket(oldest, freedBucket)
-			if !added {
-				a.Logger.Error(cmn.Fmt("Could not migrate oldest %v to freedBucket %v", oldest, freedBucket))
-			}
-		}
-		// Finally, add to bucket again.
+		a.addToNewBucket(oldest, newBucketIdx)
+
+		// Finally, add our ka to old bucket again.
 		added = a.addToOldBucket(ka, oldBucketIdx)
 		if !added {
 			a.Logger.Error(cmn.Fmt("Could not re-add ka %v to oldBucketIdx %v", ka, oldBucketIdx))

p2p/pex/errors.go

@@ -30,12 +30,3 @@ type ErrAddrBookNilAddr struct {
 func (err ErrAddrBookNilAddr) Error() string {
 	return fmt.Sprintf("Cannot add a nil address. Got (addr, src) = (%v, %v)", err.Addr, err.Src)
 }
-
-type ErrAddrBookFull struct {
-	Addr *p2p.NetAddress
-	Size int
-}
-
-func (err ErrAddrBookFull) Error() string {
-	return fmt.Sprintf("Can't add new address (%v), addr book is full (%d)", err.Addr, err.Size)
-}