Merge pull request #246 from neilalexander/metadata

NodeInfo support

src/config/config.go

@@ -19,6 +19,7 @@ type NodeConfig struct {
 	SessionFirewall             SessionFirewall        `comment:"The session firewall controls who can send/receive network traffic\nto/from. This is useful if you want to protect this node without\nresorting to using a real firewall. This does not affect traffic\nbeing routed via this node to somewhere else. Rules are prioritised as\nfollows: blacklist, whitelist, always allow outgoing, direct, remote."`
 	TunnelRouting               TunnelRouting          `comment:"Allow tunneling non-Yggdrasil traffic over Yggdrasil. This effectively\nallows you to use Yggdrasil to route to, or to bridge other networks,\nsimilar to a VPN tunnel. Tunnelling works between any two nodes and\ndoes not require them to be directly peered."`
 	SwitchOptions               SwitchOptions          `comment:"Advanced options for tuning the switch. Normally you will not need\nto edit these options."`
+	NodeInfo                    map[string]interface{} `comment:"Optional node info. This must be a { \"key\": \"value\", ... } map\nor set as null. This is entirely optional but, if set, is visible\nto the whole network on request."`
 	//Net                         NetConfig `comment:"Extended options for connecting to peers over other networks."`
 }
 

src/yggdrasil/admin.go

@@ -322,6 +322,23 @@ func (a *admin) init(c *Core, listenaddr string) {
 			return admin_info{}, err
 		}
 	})
+	a.addHandler("getNodeInfo", []string{"box_pub_key", "coords", "[nocache]"}, func(in admin_info) (admin_info, error) {
+		var nocache bool
+		if in["nocache"] != nil {
+			nocache = in["nocache"].(string) == "true"
+		}
+		result, err := a.admin_getNodeInfo(in["box_pub_key"].(string), in["coords"].(string), nocache)
+		if err == nil {
+			var m map[string]interface{}
+			if err = json.Unmarshal(result, &m); err == nil {
+				return admin_info{"nodeinfo": m}, nil
+			} else {
+				return admin_info{}, err
+			}
+		} else {
+			return admin_info{}, err
+		}
+	})
 }
 
 // start runs the admin API socket to listen for / respond to admin API calls.
@@ -800,6 +817,52 @@ func (a *admin) admin_dhtPing(keyString, coordString, targetString string) (dhtR
 	return dhtRes{}, errors.New(fmt.Sprintf("DHT ping timeout: %s", keyString))
 }
 
+func (a *admin) admin_getNodeInfo(keyString, coordString string, nocache bool) (nodeinfoPayload, error) {
+	var key boxPubKey
+	if keyBytes, err := hex.DecodeString(keyString); err != nil {
+		return nodeinfoPayload{}, err
+	} else {
+		copy(key[:], keyBytes)
+	}
+	if !nocache {
+		if response, err := a.core.nodeinfo.getCachedNodeInfo(key); err == nil {
+			return response, nil
+		}
+	}
+	var coords []byte
+	for _, cstr := range strings.Split(strings.Trim(coordString, "[]"), " ") {
+		if cstr == "" {
+			// Special case, happens if trimmed is the empty string, e.g. this is the root
+			continue
+		}
+		if u64, err := strconv.ParseUint(cstr, 10, 8); err != nil {
+			return nodeinfoPayload{}, err
+		} else {
+			coords = append(coords, uint8(u64))
+		}
+	}
+	response := make(chan *nodeinfoPayload, 1)
+	sendNodeInfoRequest := func() {
+		a.core.nodeinfo.addCallback(key, func(nodeinfo *nodeinfoPayload) {
+			defer func() { recover() }()
+			select {
+			case response <- nodeinfo:
+			default:
+			}
+		})
+		a.core.nodeinfo.sendNodeInfo(key, coords, false)
+	}
+	a.core.router.doAdmin(sendNodeInfoRequest)
+	go func() {
+		time.Sleep(6 * time.Second)
+		close(response)
+	}()
+	for res := range response {
+		return *res, nil
+	}
+	return nodeinfoPayload{}, errors.New(fmt.Sprintf("getNodeInfo timeout: %s", keyString))
+}
+
 // getResponse_dot returns a response for a graphviz dot formatted representation of the known parts of the network.
 // This is color-coded and labeled, and includes the self node, switch peers, nodes known to the DHT, and nodes with open sessions.
 // The graph is structured as a tree with directed links leading away from the root.

src/yggdrasil/core.go

@@ -31,6 +31,7 @@ type Core struct {
 	admin       admin
 	searches    searches
 	multicast   multicast
+	nodeinfo    nodeinfo
 	tcp         tcpInterface
 	log         *log.Logger
 	ifceExpr    []*regexp.Regexp // the zone of link-local IPv6 peers must match this
@@ -122,6 +123,9 @@ func (c *Core) Start(nc *config.NodeConfig, log *log.Logger) error {
 	c.init(&boxPub, &boxPriv, &sigPub, &sigPriv)
 	c.admin.init(c, nc.AdminListen)
 
+	c.nodeinfo.init(c)
+	c.nodeinfo.setNodeInfo(nc.NodeInfo)
+
 	if err := c.tcp.init(c, nc.Listen, nc.ReadTimeout); err != nil {
 		c.log.Println("Failed to start TCP interface")
 		return err
@@ -237,6 +241,16 @@ func (c *Core) GetSubnet() *net.IPNet {
 	return &net.IPNet{IP: subnet, Mask: net.CIDRMask(64, 128)}
 }
 
+// Gets the nodeinfo.
+func (c *Core) GetNodeInfo() nodeinfoPayload {
+	return c.nodeinfo.getNodeInfo()
+}
+
+// Sets the nodeinfo.
+func (c *Core) SetNodeInfo(nodeinfo interface{}) {
+	c.nodeinfo.setNodeInfo(nodeinfo)
+}
+
 // Sets the output logger of the Yggdrasil node after startup. This may be
 // useful if you want to redirect the output later.
 func (c *Core) SetLogger(log *log.Logger) {

src/yggdrasil/nodeinfo.go

@@ -0,0 +1,175 @@
+package yggdrasil
+
+import (
+	"encoding/json"
+	"errors"
+	"runtime"
+	"sync"
+	"time"
+)
+
+type nodeinfo struct {
+	core            *Core
+	myNodeInfo      nodeinfoPayload
+	myNodeInfoMutex sync.RWMutex
+	callbacks       map[boxPubKey]nodeinfoCallback
+	callbacksMutex  sync.Mutex
+	cache           map[boxPubKey]nodeinfoCached
+	cacheMutex      sync.RWMutex
+}
+
+type nodeinfoPayload []byte
+
+type nodeinfoCached struct {
+	payload nodeinfoPayload
+	created time.Time
+}
+
+type nodeinfoCallback struct {
+	call    func(nodeinfo *nodeinfoPayload)
+	created time.Time
+}
+
+// Represents a session nodeinfo packet.
+type nodeinfoReqRes struct {
+	SendPermPub boxPubKey // Sender's permanent key
+	SendCoords  []byte    // Sender's coords
+	IsResponse  bool
+	NodeInfo    nodeinfoPayload
+}
+
+// Initialises the nodeinfo cache/callback maps, and starts a goroutine to keep
+// the cache/callback maps clean of stale entries
+func (m *nodeinfo) init(core *Core) {
+	m.core = core
+	m.callbacks = make(map[boxPubKey]nodeinfoCallback)
+	m.cache = make(map[boxPubKey]nodeinfoCached)
+
+	go func() {
+		for {
+			m.callbacksMutex.Lock()
+			for boxPubKey, callback := range m.callbacks {
+				if time.Since(callback.created) > time.Minute {
+					delete(m.callbacks, boxPubKey)
+				}
+			}
+			m.callbacksMutex.Unlock()
+			m.cacheMutex.Lock()
+			for boxPubKey, cache := range m.cache {
+				if time.Since(cache.created) > time.Hour {
+					delete(m.cache, boxPubKey)
+				}
+			}
+			m.cacheMutex.Unlock()
+			time.Sleep(time.Second * 30)
+		}
+	}()
+}
+
+// Add a callback for a nodeinfo lookup
+func (m *nodeinfo) addCallback(sender boxPubKey, call func(nodeinfo *nodeinfoPayload)) {
+	m.callbacksMutex.Lock()
+	defer m.callbacksMutex.Unlock()
+	m.callbacks[sender] = nodeinfoCallback{
+		created: time.Now(),
+		call:    call,
+	}
+}
+
+// Handles the callback, if there is one
+func (m *nodeinfo) callback(sender boxPubKey, nodeinfo nodeinfoPayload) {
+	m.callbacksMutex.Lock()
+	defer m.callbacksMutex.Unlock()
+	if callback, ok := m.callbacks[sender]; ok {
+		callback.call(&nodeinfo)
+		delete(m.callbacks, sender)
+	}
+}
+
+// Get the current node's nodeinfo
+func (m *nodeinfo) getNodeInfo() nodeinfoPayload {
+	m.myNodeInfoMutex.RLock()
+	defer m.myNodeInfoMutex.RUnlock()
+	return m.myNodeInfo
+}
+
+// Set the current node's nodeinfo
+func (m *nodeinfo) setNodeInfo(given interface{}) error {
+	m.myNodeInfoMutex.Lock()
+	defer m.myNodeInfoMutex.Unlock()
+	newnodeinfo := map[string]interface{}{
+		"buildname":     GetBuildName(),
+		"buildversion":  GetBuildVersion(),
+		"buildplatform": runtime.GOOS,
+		"buildarch":     runtime.GOARCH,
+	}
+	if nodeinfomap, ok := given.(map[string]interface{}); ok {
+		for key, value := range nodeinfomap {
+			if _, ok := newnodeinfo[key]; ok {
+				continue
+			}
+			newnodeinfo[key] = value
+		}
+	}
+	if newjson, err := json.Marshal(newnodeinfo); err == nil {
+		if len(newjson) > 16384 {
+			return errors.New("NodeInfo exceeds max length of 16384 bytes")
+		}
+		m.myNodeInfo = newjson
+		return nil
+	} else {
+		return err
+	}
+}
+
+// Add nodeinfo into the cache for a node
+func (m *nodeinfo) addCachedNodeInfo(key boxPubKey, payload nodeinfoPayload) {
+	m.cacheMutex.Lock()
+	defer m.cacheMutex.Unlock()
+	m.cache[key] = nodeinfoCached{
+		created: time.Now(),
+		payload: payload,
+	}
+}
+
+// Get a nodeinfo entry from the cache
+func (m *nodeinfo) getCachedNodeInfo(key boxPubKey) (nodeinfoPayload, error) {
+	m.cacheMutex.RLock()
+	defer m.cacheMutex.RUnlock()
+	if nodeinfo, ok := m.cache[key]; ok {
+		return nodeinfo.payload, nil
+	}
+	return nodeinfoPayload{}, errors.New("No cache entry found")
+}
+
+// Handles a nodeinfo request/response - called from the router
+func (m *nodeinfo) handleNodeInfo(nodeinfo *nodeinfoReqRes) {
+	if nodeinfo.IsResponse {
+		m.callback(nodeinfo.SendPermPub, nodeinfo.NodeInfo)
+		m.addCachedNodeInfo(nodeinfo.SendPermPub, nodeinfo.NodeInfo)
+	} else {
+		m.sendNodeInfo(nodeinfo.SendPermPub, nodeinfo.SendCoords, true)
+	}
+}
+
+// Send nodeinfo request or response - called from the router
+func (m *nodeinfo) sendNodeInfo(key boxPubKey, coords []byte, isResponse bool) {
+	table := m.core.switchTable.table.Load().(lookupTable)
+	nodeinfo := nodeinfoReqRes{
+		SendCoords: table.self.getCoords(),
+		IsResponse: isResponse,
+		NodeInfo:   m.core.nodeinfo.getNodeInfo(),
+	}
+	bs := nodeinfo.encode()
+	shared := m.core.sessions.getSharedKey(&m.core.boxPriv, &key)
+	payload, nonce := boxSeal(shared, bs, nil)
+	p := wire_protoTrafficPacket{
+		Coords:  coords,
+		ToKey:   key,
+		FromKey: m.core.boxPub,
+		Nonce:   *nonce,
+		Payload: payload,
+	}
+	packet := p.encode()
+	m.core.router.out(packet)
+}

src/yggdrasil/peer.go

@@ -86,7 +86,6 @@ type peer struct {
 	shared     boxSharedKey
 	linkShared boxSharedKey
 	endpoint   string
-	friendlyName string
 	firstSeen  time.Time       // To track uptime for getPeers
 	linkOut    (chan []byte)   // used for protocol traffic (to bypass queues)
 	doSend     (chan struct{}) // tell the linkLoop to send a switchMsg

src/yggdrasil/router.go

@@ -409,6 +409,10 @@ func (r *router) handleProto(packet []byte) {
 		r.handlePing(bs, &p.FromKey)
 	case wire_SessionPong:
 		r.handlePong(bs, &p.FromKey)
+	case wire_NodeInfoRequest:
+		fallthrough
+	case wire_NodeInfoResponse:
+		r.handleNodeInfo(bs, &p.FromKey)
 	case wire_DHTLookupRequest:
 		r.handleDHTReq(bs, &p.FromKey)
 	case wire_DHTLookupResponse:
@@ -453,6 +457,16 @@ func (r *router) handleDHTRes(bs []byte, fromKey *boxPubKey) {
 	r.core.dht.handleRes(&res)
 }
 
+// Decodes nodeinfo request
+func (r *router) handleNodeInfo(bs []byte, fromKey *boxPubKey) {
+	req := nodeinfoReqRes{}
+	if !req.decode(bs) {
+		return
+	}
+	req.SendPermPub = *fromKey
+	r.core.nodeinfo.handleNodeInfo(&req)
+}
+
 // Passed a function to call.
 // This will send the function to r.admin and block until it finishes.
 // It's used by the admin socket to ask the router mainLoop goroutine about information in the session or dht structs, which cannot be read safely from outside that goroutine.

src/yggdrasil/wire.go

@@ -16,6 +16,8 @@ const (
 	wire_SessionPong                // inside protocol traffic header
 	wire_DHTLookupRequest           // inside protocol traffic header
 	wire_DHTLookupResponse          // inside protocol traffic header
+	wire_NodeInfoRequest            // inside protocol traffic header
+	wire_NodeInfoResponse           // inside protocol traffic header
 )
 
 // Calls wire_put_uint64 on a nil slice.
@@ -353,6 +355,47 @@ func (p *sessionPing) decode(bs []byte) bool {
 
 ////////////////////////////////////////////////////////////////////////////////
 
+// Encodes a nodeinfoReqRes into its wire format.
+func (p *nodeinfoReqRes) encode() []byte {
+	var pTypeVal uint64
+	if p.IsResponse {
+		pTypeVal = wire_NodeInfoResponse
+	} else {
+		pTypeVal = wire_NodeInfoRequest
+	}
+	bs := wire_encode_uint64(pTypeVal)
+	bs = wire_put_coords(p.SendCoords, bs)
+	if pTypeVal == wire_NodeInfoResponse {
+		bs = append(bs, p.NodeInfo...)
+	}
+	return bs
+}
+
+// Decodes an encoded nodeinfoReqRes into the struct, returning true if successful.
+func (p *nodeinfoReqRes) decode(bs []byte) bool {
+	var pType uint64
+	switch {
+	case !wire_chop_uint64(&pType, &bs):
+		return false
+	case pType != wire_NodeInfoRequest && pType != wire_NodeInfoResponse:
+		return false
+	case !wire_chop_coords(&p.SendCoords, &bs):
+		return false
+	}
+	if p.IsResponse = pType == wire_NodeInfoResponse; p.IsResponse {
+		if len(bs) == 0 {
+			return false
+		}
+		p.NodeInfo = make(nodeinfoPayload, len(bs))
+		if !wire_chop_slice(p.NodeInfo[:], &bs) {
+			return false
+		}
+	}
+	return true
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
 // Encodes a dhtReq into its wire format.
 func (r *dhtReq) encode() []byte {
 	coords := wire_encode_coords(r.Coords)