Headscale is from no-juan

Fix deadlock issue

README.md

@@ -24,6 +24,7 @@ Headscale implements this coordination server.
 - [x] Node registration via pre-auth keys (including reusable keys, and ephemeral node support)
 - [X] JSON-formatted output
 - [X] ACLs
+- [X] Support for alternative IP ranges in the tailnets (default Tailscale's 100.64.0.0/10)
 - [ ] Share nodes between ~~users~~ namespaces 
 - [ ] DNS
 
@@ -113,9 +114,15 @@ Headscale's configuration file is named `config.json` or `config.yaml`. Headscal
 ```
     "server_url": "http://192.168.1.12:8080",
     "listen_addr": "0.0.0.0:8080",
+    "ip_prefix": "100.64.0.0/10"
 ```
 
-`server_url` is the external URL via which Headscale is reachable. `listen_addr` is the IP address and port the Headscale program should listen on.
+`server_url` is the external URL via which Headscale is reachable. `listen_addr` is the IP address and port the Headscale program should listen on. `ip_prefix` is the IP prefix (range) in which IP addresses for nodes will be allocated (default 100.64.0.0/10, e.g., 192.168.4.0/24, 10.0.0.0/8)
+
+```
+    "log_level": "debug"
+```
+`log_level` can be used to set the Log level for Headscale, it defaults to `debug`, and the available levels are: `trace`, `debug`, `info`, `warn` and `error`.
 
 ```
     "private_key_path": "private.key",

acls.go

@@ -4,11 +4,12 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"log"
 	"os"
 	"strconv"
 	"strings"
 
+	"github.com/rs/zerolog/log"
+
 	"github.com/tailscale/hujson"
 	"inet.af/netaddr"
 	"tailscale.com/tailcfg"
@@ -66,7 +67,8 @@ func (h *Headscale) generateACLRules() (*[]tailcfg.FilterRule, error) {
 		for j, u := range a.Users {
 			srcs, err := h.generateACLPolicySrcIP(u)
 			if err != nil {
-				log.Printf("Error parsing ACL %d, User %d", i, j)
+				log.Error().
+					Msgf("Error parsing ACL %d, User %d", i, j)
 				return nil, err
 			}
 			srcIPs = append(srcIPs, *srcs...)
@@ -77,7 +79,8 @@ func (h *Headscale) generateACLRules() (*[]tailcfg.FilterRule, error) {
 		for j, d := range a.Ports {
 			dests, err := h.generateACLPolicyDestPorts(d)
 			if err != nil {
-				log.Printf("Error parsing ACL %d, Port %d", i, j)
+				log.Error().
+					Msgf("Error parsing ACL %d, Port %d", i, j)
 				return nil, err
 			}
 			destPorts = append(destPorts, *dests...)

api.go

@@ -6,10 +6,11 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"log"
 	"net/http"
 	"time"
 
+	"github.com/rs/zerolog/log"
+
 	"github.com/gin-gonic/gin"
 	"github.com/klauspost/compress/zstd"
 	"gorm.io/datatypes"
@@ -63,21 +64,27 @@ func (h *Headscale) RegistrationHandler(c *gin.Context) {
 	mKeyStr := c.Param("id")
 	mKey, err := wgkey.ParseHex(mKeyStr)
 	if err != nil {
-		log.Printf("Cannot parse machine key: %s", err)
+		log.Error().
+			Str("handler", "Registration").
+			Err(err).
+			Msg("Cannot parse machine key")
 		c.String(http.StatusInternalServerError, "Sad!")
 		return
 	}
 	req := tailcfg.RegisterRequest{}
 	err = decode(body, &req, &mKey, h.privateKey)
 	if err != nil {
-		log.Printf("Cannot decode message: %s", err)
+		log.Error().
+			Str("handler", "Registration").
+			Err(err).
+			Msg("Cannot decode message")
 		c.String(http.StatusInternalServerError, "Very sad!")
 		return
 	}
 
 	var m Machine
 	if result := h.db.Preload("Namespace").First(&m, "machine_key = ?", mKey.HexString()); errors.Is(result.Error, gorm.ErrRecordNotFound) {
-		log.Println("New Machine!")
+		log.Info().Str("machine", req.Hostinfo.Hostname).Msg("New machine")
 		m = Machine{
 			Expiry:     &req.Expiry,
 			MachineKey: mKey.HexString(),
@@ -85,7 +92,10 @@ func (h *Headscale) RegistrationHandler(c *gin.Context) {
 			NodeKey:    wgkey.Key(req.NodeKey).HexString(),
 		}
 		if err := h.db.Create(&m).Error; err != nil {
-			log.Printf("Could not create row: %s", err)
+			log.Error().
+				Str("handler", "Registration").
+				Err(err).
+				Msg("Could not create row")
 			return
 		}
 	}
@@ -100,13 +110,20 @@ func (h *Headscale) RegistrationHandler(c *gin.Context) {
 	// We have the updated key!
 	if m.NodeKey == wgkey.Key(req.NodeKey).HexString() {
 		if m.Registered {
-			log.Printf("[%s] Client is registered and we have the current NodeKey. All clear to /map", m.Name)
+			log.Debug().
+				Str("handler", "Registration").
+				Str("machine", m.Name).
+				Msg("Client is registered and we have the current NodeKey. All clear to /map")
+
 			resp.AuthURL = ""
 			resp.MachineAuthorized = true
 			resp.User = *m.Namespace.toUser()
 			respBody, err := encode(resp, &mKey, h.privateKey)
 			if err != nil {
-				log.Printf("Cannot encode message: %s", err)
+				log.Error().
+					Str("handler", "Registration").
+					Err(err).
+					Msg("Cannot encode message")
 				c.String(http.StatusInternalServerError, "")
 				return
 			}
@@ -114,12 +131,18 @@ func (h *Headscale) RegistrationHandler(c *gin.Context) {
 			return
 		}
 
-		log.Printf("[%s] Not registered and not NodeKey rotation. Sending a authurl to register", m.Name)
+		log.Debug().
+			Str("handler", "Registration").
+			Str("machine", m.Name).
+			Msg("Not registered and not NodeKey rotation. Sending a authurl to register")
 		resp.AuthURL = fmt.Sprintf("%s/register?key=%s",
 			h.cfg.ServerURL, mKey.HexString())
 		respBody, err := encode(resp, &mKey, h.privateKey)
 		if err != nil {
-			log.Printf("Cannot encode message: %s", err)
+			log.Error().
+				Str("handler", "Registration").
+				Err(err).
+				Msg("Cannot encode message")
 			c.String(http.StatusInternalServerError, "")
 			return
 		}
@@ -129,7 +152,10 @@ func (h *Headscale) RegistrationHandler(c *gin.Context) {
 
 	// The NodeKey we have matches OldNodeKey, which means this is a refresh after an key expiration
 	if m.NodeKey == wgkey.Key(req.OldNodeKey).HexString() {
-		log.Printf("[%s] We have the OldNodeKey in the database. This is a key refresh", m.Name)
+		log.Debug().
+			Str("handler", "Registration").
+			Str("machine", m.Name).
+			Msg("We have the OldNodeKey in the database. This is a key refresh")
 		m.NodeKey = wgkey.Key(req.NodeKey).HexString()
 		h.db.Save(&m)
 
@@ -137,7 +163,10 @@ func (h *Headscale) RegistrationHandler(c *gin.Context) {
 		resp.User = *m.Namespace.toUser()
 		respBody, err := encode(resp, &mKey, h.privateKey)
 		if err != nil {
-			log.Printf("Cannot encode message: %s", err)
+			log.Error().
+				Str("handler", "Registration").
+				Err(err).
+				Msg("Cannot encode message")
 			c.String(http.StatusInternalServerError, "Extremely sad!")
 			return
 		}
@@ -148,25 +177,38 @@ func (h *Headscale) RegistrationHandler(c *gin.Context) {
 	// We arrive here after a client is restarted without finalizing the authentication flow or
 	// when headscale is stopped in the middle of the auth process.
 	if m.Registered {
-		log.Printf("[%s] The node is sending us a new NodeKey, but machine is registered. All clear for /map", m.Name)
+		log.Debug().
+			Str("handler", "Registration").
+			Str("machine", m.Name).
+			Msg("The node is sending us a new NodeKey, but machine is registered. All clear for /map")
 		resp.AuthURL = ""
 		resp.MachineAuthorized = true
 		resp.User = *m.Namespace.toUser()
 		respBody, err := encode(resp, &mKey, h.privateKey)
 		if err != nil {
-			log.Printf("Cannot encode message: %s", err)
+			log.Error().
+				Str("handler", "Registration").
+				Err(err).
+				Msg("Cannot encode message")
 			c.String(http.StatusInternalServerError, "")
 			return
 		}
 		c.Data(200, "application/json; charset=utf-8", respBody)
 		return
 	}
-	log.Printf("[%s] The node is sending us a new NodeKey, sending auth url", m.Name)
+
+	log.Debug().
+		Str("handler", "Registration").
+		Str("machine", m.Name).
+		Msg("The node is sending us a new NodeKey, sending auth url")
 	resp.AuthURL = fmt.Sprintf("%s/register?key=%s",
 		h.cfg.ServerURL, mKey.HexString())
 	respBody, err := encode(resp, &mKey, h.privateKey)
 	if err != nil {
-		log.Printf("Cannot encode message: %s", err)
+		log.Error().
+			Str("handler", "Registration").
+			Err(err).
+			Msg("Cannot encode message")
 		c.String(http.StatusInternalServerError, "")
 		return
 	}
@@ -183,28 +225,45 @@ func (h *Headscale) RegistrationHandler(c *gin.Context) {
 //
 // At this moment the updates are sent in a quite horrendous way, but they kinda work.
 func (h *Headscale) PollNetMapHandler(c *gin.Context) {
+	log.Trace().
+		Str("handler", "PollNetMap").
+		Str("id", c.Param("id")).
+		Msg("PollNetMapHandler called")
 	body, _ := io.ReadAll(c.Request.Body)
 	mKeyStr := c.Param("id")
 	mKey, err := wgkey.ParseHex(mKeyStr)
 	if err != nil {
-		log.Printf("Cannot parse client key: %s", err)
+		log.Error().
+			Str("handler", "PollNetMap").
+			Err(err).
+			Msg("Cannot parse client key")
 		c.String(http.StatusBadRequest, "")
 		return
 	}
 	req := tailcfg.MapRequest{}
 	err = decode(body, &req, &mKey, h.privateKey)
 	if err != nil {
-		log.Printf("Cannot decode message: %s", err)
+		log.Error().
+			Str("handler", "PollNetMap").
+			Err(err).
+			Msg("Cannot decode message")
 		c.String(http.StatusBadRequest, "")
 		return
 	}
 
 	var m Machine
 	if result := h.db.Preload("Namespace").First(&m, "machine_key = ?", mKey.HexString()); errors.Is(result.Error, gorm.ErrRecordNotFound) {
-		log.Printf("Ignoring request, cannot find machine with key %s", mKey.HexString())
+		log.Warn().
+			Str("handler", "PollNetMap").
+			Msgf("Ignoring request, cannot find machine with key %s", mKey.HexString())
 		c.String(http.StatusUnauthorized, "")
 		return
 	}
+	log.Trace().
+		Str("handler", "PollNetMap").
+		Str("id", c.Param("id")).
+		Str("machine", m.Name).
+		Msg("Found machine in database")
 
 	hostinfo, _ := json.Marshal(req.Hostinfo)
 	m.Name = req.Hostinfo.Hostname
@@ -227,17 +286,34 @@ func (h *Headscale) PollNetMapHandler(c *gin.Context) {
 	}
 	h.db.Save(&m)
 
-	pollData := make(chan []byte, 1)
 	update := make(chan []byte, 1)
-	cancelKeepAlive := make(chan []byte, 1)
+
+	pollData := make(chan []byte, 1)
 	defer close(pollData)
+
+	cancelKeepAlive := make(chan []byte, 1)
 	defer close(cancelKeepAlive)
-	h.pollMu.Lock()
-	h.clientsPolling[m.ID] = update
-	h.pollMu.Unlock()
+
+	log.Trace().
+		Str("handler", "PollNetMap").
+		Str("id", c.Param("id")).
+		Str("machine", m.Name).
+		Msg("Locking poll mutex")
+	h.clientsPolling.Store(m.ID, update)
+	log.Trace().
+		Str("handler", "PollNetMap").
+		Str("id", c.Param("id")).
+		Str("machine", m.Name).
+		Msg("Unlocking poll mutex")
 
 	data, err := h.getMapResponse(mKey, req, m)
 	if err != nil {
+		log.Error().
+			Str("handler", "PollNetMap").
+			Str("id", c.Param("id")).
+			Str("machine", m.Name).
+			Err(err).
+			Msg("Failed to get Map response")
 		c.String(http.StatusInternalServerError, ":(")
 		return
 	}
@@ -247,50 +323,90 @@ func (h *Headscale) PollNetMapHandler(c *gin.Context) {
 	// empty endpoints to peers)
 
 	// Details on the protocol can be found in https://github.com/tailscale/tailscale/blob/main/tailcfg/tailcfg.go#L696
-	log.Printf("[%s] ReadOnly=%t   OmitPeers=%t    Stream=%t", m.Name, req.ReadOnly, req.OmitPeers, req.Stream)
+	log.Debug().
+		Str("handler", "PollNetMap").
+		Str("id", c.Param("id")).
+		Str("machine", m.Name).
+		Bool("readOnly", req.ReadOnly).
+		Bool("omitPeers", req.OmitPeers).
+		Bool("stream", req.Stream).
+		Msg("Client map request processed")
 
 	if req.ReadOnly {
-		log.Printf("[%s] Client is starting up. Asking for DERP map", m.Name)
+		log.Info().
+			Str("handler", "PollNetMap").
+			Str("machine", m.Name).
+			Msg("Client is starting up. Asking for DERP map")
 		c.Data(200, "application/json; charset=utf-8", *data)
 		return
 	}
 	if req.OmitPeers && !req.Stream {
-		log.Printf("[%s] Client sent endpoint update and is ok with a response without peer list", m.Name)
+		log.Info().
+			Str("handler", "PollNetMap").
+			Str("machine", m.Name).
+			Msg("Client sent endpoint update and is ok with a response without peer list")
 		c.Data(200, "application/json; charset=utf-8", *data)
 		return
 	} else if req.OmitPeers && req.Stream {
-		log.Printf("[%s] Warning, ignoring request, don't know how to handle it", m.Name)
+		log.Warn().
+			Str("handler", "PollNetMap").
+			Str("machine", m.Name).
+			Msg("Ignoring request, don't know how to handle it")
 		c.String(http.StatusBadRequest, "")
 		return
 	}
 
-	log.Printf("[%s] Client is ready to access the tailnet", m.Name)
-	log.Printf("[%s] Sending initial map", m.Name)
+	log.Info().
+		Str("handler", "PollNetMap").
+		Str("machine", m.Name).
+		Msg("Client is ready to access the tailnet")
+	log.Info().
+		Str("handler", "PollNetMap").
+		Str("machine", m.Name).
+		Msg("Sending initial map")
 	pollData <- *data
 
-	log.Printf("[%s] Notifying peers", m.Name)
+	log.Info().
+		Str("handler", "PollNetMap").
+		Str("machine", m.Name).
+		Msg("Notifying peers")
 	peers, _ := h.getPeers(m)
-	h.pollMu.Lock()
 	for _, p := range *peers {
-		pUp, ok := h.clientsPolling[uint64(p.ID)]
+		pUp, ok := h.clientsPolling.Load(uint64(p.ID))
 		if ok {
-			log.Printf("[%s] Notifying peer %s (%s)", m.Name, p.Name, p.Addresses[0])
-			pUp <- []byte{}
+			log.Info().
+				Str("handler", "PollNetMap").
+				Str("machine", m.Name).
+				Str("peer", m.Name).
+				Str("address", p.Addresses[0].String()).
+				Msgf("Notifying peer %s (%s)", p.Name, p.Addresses[0])
+			pUp.(chan []byte) <- []byte{}
 		} else {
-			log.Printf("[%s] Peer %s does not appear to be polling", m.Name, p.Name)
+			log.Info().
+				Str("handler", "PollNetMap").
+				Str("machine", m.Name).
+				Str("peer", m.Name).
+				Msgf("Peer %s does not appear to be polling", p.Name)
 		}
 	}
-	h.pollMu.Unlock()
 
 	go h.keepAlive(cancelKeepAlive, pollData, mKey, req, m)
 
 	c.Stream(func(w io.Writer) bool {
 		select {
 		case data := <-pollData:
-			log.Printf("[%s] Sending data (%d bytes)", m.Name, len(data))
+			log.Trace().
+				Str("handler", "PollNetMap").
+				Str("machine", m.Name).
+				Int("bytes", len(data)).
+				Msg("Sending data")
 			_, err := w.Write(data)
 			if err != nil {
-				log.Printf("[%s] Cannot write data: %s", m.Name, err)
+				log.Error().
+					Str("handler", "PollNetMap").
+					Str("machine", m.Name).
+					Err(err).
+					Msg("Cannot write data")
 			}
 			now := time.Now().UTC()
 			m.LastSeen = &now
@@ -298,27 +414,39 @@ func (h *Headscale) PollNetMapHandler(c *gin.Context) {
 			return true
 
 		case <-update:
-			log.Printf("[%s] Received a request for update", m.Name)
+			log.Debug().
+				Str("handler", "PollNetMap").
+				Str("machine", m.Name).
+				Msg("Received a request for update")
 			data, err := h.getMapResponse(mKey, req, m)
 			if err != nil {
-				log.Printf("[%s] Could not get the map update: %s", m.Name, err)
+				log.Error().
+					Str("handler", "PollNetMap").
+					Str("machine", m.Name).
+					Err(err).
+					Msg("Could not get the map update")
 			}
 			_, err = w.Write(*data)
 			if err != nil {
-				log.Printf("[%s] Could not write the map response: %s", m.Name, err)
+				log.Error().
+					Str("handler", "PollNetMap").
+					Str("machine", m.Name).
+					Err(err).
+					Msg("Could not write the map response")
 			}
 			return true
 
 		case <-c.Request.Context().Done():
-			log.Printf("[%s] The client has closed the connection", m.Name)
+			log.Info().
+				Str("handler", "PollNetMap").
+				Str("machine", m.Name).
+				Msg("The client has closed the connection")
 			now := time.Now().UTC()
 			m.LastSeen = &now
 			h.db.Save(&m)
-			h.pollMu.Lock()
 			cancelKeepAlive <- []byte{}
-			delete(h.clientsPolling, m.ID)
+			h.clientsPolling.Delete(m.ID)
 			close(update)
-			h.pollMu.Unlock()
 			return false
 
 		}
@@ -335,10 +463,16 @@ func (h *Headscale) keepAlive(cancel chan []byte, pollData chan []byte, mKey wgk
 			h.pollMu.Lock()
 			data, err := h.getMapKeepAliveResponse(mKey, req, m)
 			if err != nil {
-				log.Printf("Error generating the keep alive msg: %s", err)
+				log.Error().
+					Str("func", "keepAlive").
+					Err(err).
+					Msg("Error generating the keep alive msg")
 				return
 			}
-			log.Printf("[%s] Sending keepalive", m.Name)
+			log.Debug().
+				Str("func", "keepAlive").
+				Str("machine", m.Name).
+				Msg("Sending keepalive")
 			pollData <- *data
 			h.pollMu.Unlock()
 			time.Sleep(60 * time.Second)
@@ -347,14 +481,24 @@ func (h *Headscale) keepAlive(cancel chan []byte, pollData chan []byte, mKey wgk
 }
 
 func (h *Headscale) getMapResponse(mKey wgkey.Key, req tailcfg.MapRequest, m Machine) (*[]byte, error) {
+	log.Trace().
+		Str("func", "getMapResponse").
+		Str("machine", req.Hostinfo.Hostname).
+		Msg("Creating Map response")
 	node, err := m.toNode()
 	if err != nil {
-		log.Printf("Cannot convert to node: %s", err)
+		log.Error().
+			Str("func", "getMapResponse").
+			Err(err).
+			Msg("Cannot convert to node")
 		return nil, err
 	}
 	peers, err := h.getPeers(m)
 	if err != nil {
-		log.Printf("Cannot fetch peers: %s", err)
+		log.Error().
+			Str("func", "getMapResponse").
+			Err(err).
+			Msg("Cannot fetch peers")
 		return nil, err
 	}
 
@@ -426,25 +570,49 @@ func (h *Headscale) getMapKeepAliveResponse(mKey wgkey.Key, req tailcfg.MapReque
 }
 
 func (h *Headscale) handleAuthKey(c *gin.Context, db *gorm.DB, idKey wgkey.Key, req tailcfg.RegisterRequest, m Machine) {
+	log.Debug().
+		Str("func", "handleAuthKey").
+		Str("machine", req.Hostinfo.Hostname).
+		Msgf("Processing auth key for %s", req.Hostinfo.Hostname)
 	resp := tailcfg.RegisterResponse{}
 	pak, err := h.checkKeyValidity(req.Auth.AuthKey)
 	if err != nil {
 		resp.MachineAuthorized = false
 		respBody, err := encode(resp, &idKey, h.privateKey)
 		if err != nil {
-			log.Printf("Cannot encode message: %s", err)
+			log.Error().
+				Str("func", "handleAuthKey").
+				Str("machine", m.Name).
+				Err(err).
+				Msg("Cannot encode message")
 			c.String(http.StatusInternalServerError, "")
 			return
 		}
 		c.Data(200, "application/json; charset=utf-8", respBody)
-		log.Printf("[%s] Failed authentication via AuthKey", m.Name)
+		log.Error().
+			Str("func", "handleAuthKey").
+			Str("machine", m.Name).
+			Msg("Failed authentication via AuthKey")
 		return
 	}
+
+	log.Debug().
+		Str("func", "handleAuthKey").
+		Str("machine", m.Name).
+		Msg("Authentication key was valid, proceeding to acquire an IP address")
 	ip, err := h.getAvailableIP()
 	if err != nil {
-		log.Println(err)
+		log.Error().
+			Str("func", "handleAuthKey").
+			Str("machine", m.Name).
+			Msg("Failed to find an available IP")
 		return
 	}
+	log.Info().
+		Str("func", "handleAuthKey").
+		Str("machine", m.Name).
+		Str("ip", ip.String()).
+		Msgf("Assining %s to %s", ip, m.Name)
 
 	m.AuthKeyID = uint(pak.ID)
 	m.IPAddress = ip.String()
@@ -458,10 +626,18 @@ func (h *Headscale) handleAuthKey(c *gin.Context, db *gorm.DB, idKey wgkey.Key,
 	resp.User = *pak.Namespace.toUser()
 	respBody, err := encode(resp, &idKey, h.privateKey)
 	if err != nil {
-		log.Printf("Cannot encode message: %s", err)
+		log.Error().
+			Str("func", "handleAuthKey").
+			Str("machine", m.Name).
+			Err(err).
+			Msg("Cannot encode message")
 		c.String(http.StatusInternalServerError, "Extremely sad!")
 		return
 	}
 	c.Data(200, "application/json; charset=utf-8", respBody)
-	log.Printf("[%s] Successfully authenticated via AuthKey", m.Name)
+	log.Info().
+		Str("func", "handleAuthKey").
+		Str("machine", m.Name).
+		Str("ip", ip.String()).
+		Msg("Successfully authenticated via AuthKey")
 }

app.go

@@ -3,16 +3,18 @@ package headscale
 import (
 	"errors"
 	"fmt"
-	"log"
 	"net/http"
 	"os"
 	"strings"
 	"sync"
 	"time"
 
+	"github.com/rs/zerolog/log"
+
 	"github.com/gin-gonic/gin"
 	"golang.org/x/crypto/acme/autocert"
 	"gorm.io/gorm"
+	"inet.af/netaddr"
 	"tailscale.com/tailcfg"
 	"tailscale.com/types/wgkey"
 )
@@ -24,6 +26,7 @@ type Config struct {
 	PrivateKeyPath                 string
 	DerpMap                        *tailcfg.DERPMap
 	EphemeralNodeInactivityTimeout time.Duration
+	IPPrefix                       netaddr.IPPrefix
 
 	DBtype string
 	DBpath string
@@ -56,7 +59,7 @@ type Headscale struct {
 	aclRules  *[]tailcfg.FilterRule
 
 	pollMu         sync.Mutex
-	clientsPolling map[uint64]chan []byte // this is by all means a hackity hack
+	clientsPolling sync.Map
 }
 
 // NewHeadscale returns the Headscale app
@@ -96,7 +99,6 @@ func NewHeadscale(cfg Config) (*Headscale, error) {
 		return nil, err
 	}
 
-	h.clientsPolling = make(map[uint64]chan []byte)
 	return &h, nil
 }
 
@@ -118,27 +120,41 @@ func (h *Headscale) ExpireEphemeralNodes(milliSeconds int64) {
 func (h *Headscale) expireEphemeralNodesWorker() {
 	namespaces, err := h.ListNamespaces()
 	if err != nil {
-		log.Printf("Error listing namespaces: %s", err)
+		log.Error().Err(err).Msg("Error listing namespaces")
 		return
 	}
 	for _, ns := range *namespaces {
 		machines, err := h.ListMachinesInNamespace(ns.Name)
 		if err != nil {
-			log.Printf("Error listing machines in namespace %s: %s", ns.Name, err)
+			log.Error().Err(err).Str("namespace", ns.Name).Msg("Error listing machines in namespace")
 			return
 		}
 		for _, m := range *machines {
 			if m.AuthKey != nil && m.LastSeen != nil && m.AuthKey.Ephemeral && time.Now().After(m.LastSeen.Add(h.cfg.EphemeralNodeInactivityTimeout)) {
-				log.Printf("[%s] Ephemeral client removed from database\n", m.Name)
+				log.Info().Str("machine", m.Name).Msg("Ephemeral client removed from database")
 				err = h.db.Unscoped().Delete(m).Error
 				if err != nil {
-					log.Printf("[%s] 🤮 Cannot delete ephemeral machine from the database: %s", m.Name, err)
+					log.Error().Err(err).Str("machine", m.Name).Msg("🤮 Cannot delete ephemeral machine from the database")
 				}
 			}
 		}
 	}
 }
 
+// WatchForKVUpdates checks the KV DB table for requests to perform tailnet upgrades
+// This is a way to communitate the CLI with the headscale server
+func (h *Headscale) watchForKVUpdates(milliSeconds int64) {
+	ticker := time.NewTicker(time.Duration(milliSeconds) * time.Millisecond)
+	for range ticker.C {
+		h.watchForKVUpdatesWorker()
+	}
+}
+
+func (h *Headscale) watchForKVUpdatesWorker() {
+	h.checkForNamespacesPendingUpdates()
+	// more functions will come here in the future
+}
+
 // Serve launches a GIN server with the Headscale API
 func (h *Headscale) Serve() error {
 	r := gin.Default()
@@ -147,9 +163,12 @@ func (h *Headscale) Serve() error {
 	r.POST("/machine/:id/map", h.PollNetMapHandler)
 	r.POST("/machine/:id", h.RegistrationHandler)
 	var err error
+
+	go h.watchForKVUpdates(5000)
+
 	if h.cfg.TLSLetsEncryptHostname != "" {
 		if !strings.HasPrefix(h.cfg.ServerURL, "https://") {
-			log.Println("WARNING: listening with TLS but ServerURL does not start with https://")
+			log.Warn().Msg("Listening with TLS but ServerURL does not start with https://")
 		}
 
 		m := autocert.Manager{
@@ -172,7 +191,10 @@ func (h *Headscale) Serve() error {
 			// port 80 for the certificate validation in addition to the headscale
 			// service, which can be configured to run on any other port.
 			go func() {
-				log.Fatal(http.ListenAndServe(h.cfg.TLSLetsEncryptListen, m.HTTPHandler(http.HandlerFunc(h.redirect))))
+
+				log.Fatal().
+					Err(http.ListenAndServe(h.cfg.TLSLetsEncryptListen, m.HTTPHandler(http.HandlerFunc(h.redirect)))).
+					Msg("failed to set up a HTTP server")
 			}()
 			err = s.ListenAndServeTLS("", "")
 		} else {
@@ -180,12 +202,12 @@ func (h *Headscale) Serve() error {
 		}
 	} else if h.cfg.TLSCertPath == "" {
 		if !strings.HasPrefix(h.cfg.ServerURL, "http://") {
-			log.Println("WARNING: listening without TLS but ServerURL does not start with http://")
+			log.Warn().Msg("Listening without TLS but ServerURL does not start with http://")
 		}
 		err = r.Run(h.cfg.Addr)
 	} else {
 		if !strings.HasPrefix(h.cfg.ServerURL, "https://") {
-			log.Println("WARNING: listening with TLS but ServerURL does not start with https://")
+			log.Warn().Msg("Listening with TLS but ServerURL does not start with https://")
 		}
 		err = r.RunTLS(h.cfg.Addr, h.cfg.TLSCertPath, h.cfg.TLSKeyPath)
 	}

app_test.go

@@ -6,6 +6,7 @@ import (
 	"testing"
 
 	"gopkg.in/check.v1"
+	"inet.af/netaddr"
 )
 
 func Test(t *testing.T) {
@@ -36,7 +37,9 @@ func (s *Suite) ResetDB(c *check.C) {
 	if err != nil {
 		c.Fatal(err)
 	}
-	cfg := Config{}
+	cfg := Config{
+		IPPrefix: netaddr.MustParseIPPrefix("10.27.0.0/23"),
+	}
 
 	h = Headscale{
 		cfg:      cfg,

cli_test.go

@@ -15,6 +15,7 @@ func (s *Suite) TestRegisterMachine(c *check.C) {
 		DiscoKey:    "faa",
 		Name:        "testmachine",
 		NamespaceID: n.ID,
+		IPAddress:   "10.0.0.1",
 	}
 	h.db.Save(&m)
 

cmd/headscale/cli/root.go

@@ -2,8 +2,9 @@ package cli
 
 import (
 	"fmt"
-	"github.com/spf13/cobra"
 	"os"
+
+	"github.com/spf13/cobra"
 )
 
 func init() {
@@ -16,8 +17,7 @@ var rootCmd = &cobra.Command{
 	Long: `
 headscale is an open source implementation of the Tailscale control server
 
-Juan Font Alonso <juanfontalonso@gmail.com> - 2021
-https://gitlab.com/juanfont/headscale`,
+https://github.com/juanfont/headscale`,
 }
 
 func Execute() {

cmd/headscale/cli/utils.go

@@ -5,15 +5,16 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"log"
 	"os"
 	"path/filepath"
 	"strings"
 	"time"
 
 	"github.com/juanfont/headscale"
+	"github.com/rs/zerolog/log"
 	"github.com/spf13/viper"
 	"gopkg.in/yaml.v2"
+	"inet.af/netaddr"
 	"tailscale.com/tailcfg"
 )
 
@@ -36,6 +37,10 @@ func LoadConfig(path string) error {
 	viper.SetDefault("tls_letsencrypt_cache_dir", "/var/www/.cache")
 	viper.SetDefault("tls_letsencrypt_challenge_type", "HTTP-01")
 
+	viper.SetDefault("ip_prefix", "100.64.0.0/10")
+
+	viper.SetDefault("log_level", "debug")
+
 	err := viper.ReadInConfig()
 	if err != nil {
 		return fmt.Errorf("Fatal error reading config file: %s \n", err)
@@ -49,7 +54,8 @@ func LoadConfig(path string) error {
 
 	if (viper.GetString("tls_letsencrypt_hostname") != "") && (viper.GetString("tls_letsencrypt_challenge_type") == "TLS-ALPN-01") && (!strings.HasSuffix(viper.GetString("listen_addr"), ":443")) {
 		// this is only a warning because there could be something sitting in front of headscale that redirects the traffic (e.g. an iptables rule)
-		log.Println("Warning: when using tls_letsencrypt_hostname with TLS-ALPN-01 as challenge type, headscale must be reachable on port 443, i.e. listen_addr should probably end in :443")
+		log.Warn().
+			Msg("Warning: when using tls_letsencrypt_hostname with TLS-ALPN-01 as challenge type, headscale must be reachable on port 443, i.e. listen_addr should probably end in :443")
 	}
 
 	if (viper.GetString("tls_letsencrypt_challenge_type") != "HTTP-01") && (viper.GetString("tls_letsencrypt_challenge_type") != "TLS-ALPN-01") {
@@ -79,9 +85,13 @@ func absPath(path string) string {
 }
 
 func getHeadscaleApp() (*headscale.Headscale, error) {
-	derpMap, err := loadDerpMap(absPath(viper.GetString("derp_map_path")))
+	derpPath := absPath(viper.GetString("derp_map_path"))
+	derpMap, err := loadDerpMap(derpPath)
 	if err != nil {
-		log.Printf("Could not load DERP servers map file: %s", err)
+		log.Error().
+			Str("path", derpPath).
+			Err(err).
+			Msg("Could not load DERP servers map file")
 	}
 
 	// Minimum inactivity time out is keepalive timeout (60s) plus a few seconds
@@ -97,6 +107,7 @@ func getHeadscaleApp() (*headscale.Headscale, error) {
 		Addr:           viper.GetString("listen_addr"),
 		PrivateKeyPath: absPath(viper.GetString("private_key_path")),
 		DerpMap:        derpMap,
+		IPPrefix:       netaddr.MustParseIPPrefix(viper.GetString("ip_prefix")),
 
 		EphemeralNodeInactivityTimeout: viper.GetDuration("ephemeral_node_inactivity_timeout"),
 
@@ -125,9 +136,13 @@ func getHeadscaleApp() (*headscale.Headscale, error) {
 	// We are doing this here, as in the future could be cool to have it also hot-reload
 
 	if viper.GetString("acl_policy_path") != "" {
-		err = h.LoadACLPolicy(absPath(viper.GetString("acl_policy_path")))
+		aclPath := absPath(viper.GetString("acl_policy_path"))
+		err = h.LoadACLPolicy(aclPath)
 		if err != nil {
-			log.Printf("Could not load the ACL policy: %s", err)
+			log.Error().
+				Str("path", aclPath).
+				Err(err).
+				Msg("Could not load the ACL policy")
 		}
 	}
 
@@ -157,24 +172,24 @@ func JsonOutput(result interface{}, errResult error, outputFormat string) {
 		if errResult != nil {
 			j, err = json.MarshalIndent(ErrorOutput{errResult.Error()}, "", "\t")
 			if err != nil {
-				log.Fatalln(err)
+				log.Fatal().Err(err)
 			}
 		} else {
 			j, err = json.MarshalIndent(result, "", "\t")
 			if err != nil {
-				log.Fatalln(err)
+				log.Fatal().Err(err)
 			}
 		}
 	case "json-line":
 		if errResult != nil {
 			j, err = json.Marshal(ErrorOutput{errResult.Error()})
 			if err != nil {
-				log.Fatalln(err)
+				log.Fatal().Err(err)
 			}
 		} else {
 			j, err = json.Marshal(result)
 			if err != nil {
-				log.Fatalln(err)
+				log.Fatal().Err(err)
 			}
 		}
 	}

cmd/headscale/headscale.go

@@ -1,15 +1,41 @@
 package main
 
 import (
-	"log"
+	"os"
+	"time"
 
 	"github.com/juanfont/headscale/cmd/headscale/cli"
+	"github.com/rs/zerolog"
+	"github.com/rs/zerolog/log"
+	"github.com/spf13/viper"
 )
 
 func main() {
+	zerolog.TimeFieldFormat = zerolog.TimeFormatUnix
+	log.Logger = log.Output(zerolog.ConsoleWriter{
+		Out:        os.Stdout,
+		TimeFormat: time.RFC3339,
+	})
+
 	err := cli.LoadConfig("")
 	if err != nil {
-		log.Fatalf(err.Error())
+		log.Fatal().Err(err)
+	}
+
+	logLevel := viper.GetString("log_level")
+	switch logLevel {
+	case "trace":
+		zerolog.SetGlobalLevel(zerolog.TraceLevel)
+	case "debug":
+		zerolog.SetGlobalLevel(zerolog.DebugLevel)
+	case "info":
+		zerolog.SetGlobalLevel(zerolog.InfoLevel)
+	case "warn":
+		zerolog.SetGlobalLevel(zerolog.WarnLevel)
+	case "error":
+		zerolog.SetGlobalLevel(zerolog.ErrorLevel)
+	default:
+		zerolog.SetGlobalLevel(zerolog.DebugLevel)
 	}
 
 	cli.Execute()

db.go

@@ -79,6 +79,7 @@ func (h *Headscale) openDB() (*gorm.DB, error) {
 	return db, nil
 }
 
+// getValue returns the value for the given key in KV
 func (h *Headscale) getValue(key string) (string, error) {
 	var row KV
 	if result := h.db.First(&row, "key = ?", key); errors.Is(result.Error, gorm.ErrRecordNotFound) {
@@ -87,6 +88,7 @@ func (h *Headscale) getValue(key string) (string, error) {
 	return row.Value, nil
 }
 
+// setValue sets value for the given key in KV
 func (h *Headscale) setValue(key string, value string) error {
 	kv := KV{
 		Key:   key,

go.mod

@@ -9,6 +9,7 @@ require (
 	github.com/klauspost/compress v1.13.1
 	github.com/lib/pq v1.10.2 // indirect
 	github.com/mattn/go-sqlite3 v1.14.7 // indirect
+	github.com/rs/zerolog v1.23.0 // indirect
 	github.com/spf13/cobra v1.1.3
 	github.com/spf13/viper v1.8.1
 	github.com/tailscale/hujson v0.0.0-20200924210142-dde312d0d6a2

go.sum

@@ -683,6 +683,8 @@ github.com/rogpeppe/go-internal v1.6.2/go.mod h1:xXDCJY+GAPziupqXw64V24skbSoqbTE
 github.com/rs/xid v1.2.1/go.mod h1:+uKXf+4Djp6Md1KODXJxgGQPKngRmWyn10oCKFzNHOQ=
 github.com/rs/zerolog v1.13.0/go.mod h1:YbFCdg8HfsridGWAh22vktObvhZbQsZXe4/zB0OKkWU=
 github.com/rs/zerolog v1.15.0/go.mod h1:xYTKnLHcpfU2225ny5qZjxnj9NvkumZYjJHlAThCjNc=
+github.com/rs/zerolog v1.23.0 h1:UskrK+saS9P9Y789yNNulYKdARjPZuS35B8gJF2x60g=
+github.com/rs/zerolog v1.23.0/go.mod h1:6c7hFfxPOy7TacJc4Fcdi24/J0NKYGzjG8FWRI916Qo=
 github.com/russross/blackfriday/v2 v2.0.1/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/ryancurrah/gomodguard v1.1.0/go.mod h1:4O8tr7hBODaGE6VIhfJDHcwzh5GUccKSJBU0UMXJFVM=
 github.com/ryanrolds/sqlclosecheck v0.3.0/go.mod h1:1gREqxyTGR3lVtpngyFo3hZAgk0KCtEdgEkHwDbigdA=

k8s/README.md

@@ -65,7 +65,6 @@ tasks like creating namespaces, authkeys, etc.
 
 headscale is an open source implementation of the Tailscale control server
 
-Juan Font Alonso <juanfontalonso@gmail.com> - 2021
 https://gitlab.com/juanfont/headscale
 
 Usage:

machine.go

@@ -3,11 +3,12 @@ package headscale
 import (
 	"encoding/json"
 	"fmt"
-	"log"
 	"sort"
 	"strconv"
 	"time"
 
+	"github.com/rs/zerolog/log"
+
 	"gorm.io/datatypes"
 	"inet.af/netaddr"
 	"tailscale.com/tailcfg"
@@ -157,7 +158,7 @@ func (h *Headscale) getPeers(m Machine) (*[]*tailcfg.Node, error) {
 	machines := []Machine{}
 	if err := h.db.Where("namespace_id = ? AND machine_key <> ? AND registered",
 		m.NamespaceID, m.MachineKey).Find(&machines).Error; err != nil {
-		log.Printf("Error accessing db: %s", err)
+		log.Error().Err(err).Msg("Error accessing db")
 		return nil, err
 	}
 
@@ -200,19 +201,22 @@ func (h *Headscale) GetMachineByID(id uint64) (*Machine, error) {
 // DeleteMachine softs deletes a Machine from the database
 func (h *Headscale) DeleteMachine(m *Machine) error {
 	m.Registered = false
+	namespaceID := m.NamespaceID
 	h.db.Save(&m) // we mark it as unregistered, just in case
 	if err := h.db.Delete(&m).Error; err != nil {
 		return err
 	}
-	return nil
+
+	return h.RequestMapUpdates(namespaceID)
 }
 
 // HardDeleteMachine hard deletes a Machine from the database
 func (h *Headscale) HardDeleteMachine(m *Machine) error {
+	namespaceID := m.NamespaceID
 	if err := h.db.Unscoped().Delete(&m).Error; err != nil {
 		return err
 	}
-	return nil
+	return h.RequestMapUpdates(namespaceID)
 }
 
 // GetHostInfo returns a Hostinfo struct for the machine

machine_test.go

@@ -1,6 +1,8 @@
 package headscale
 
 import (
+	"encoding/json"
+
 	"gopkg.in/check.v1"
 )
 
@@ -81,6 +83,15 @@ func (s *Suite) TestDeleteMachine(c *check.C) {
 	h.db.Save(&m)
 	err = h.DeleteMachine(&m)
 	c.Assert(err, check.IsNil)
+	v, err := h.getValue("namespaces_pending_updates")
+	c.Assert(err, check.IsNil)
+	names := []string{}
+	err = json.Unmarshal([]byte(v), &names)
+	c.Assert(err, check.IsNil)
+	c.Assert(names, check.DeepEquals, []string{n.Name})
+	h.checkForNamespacesPendingUpdates()
+	v, _ = h.getValue("namespaces_pending_updates")
+	c.Assert(v, check.Equals, "")
 	_, err = h.GetMachine(n.Name, "testmachine")
 	c.Assert(err, check.NotNil)
 }

namespaces.go

@@ -1,10 +1,12 @@
 package headscale
 
 import (
+	"encoding/json"
 	"errors"
-	"log"
+	"fmt"
 	"time"
 
+	"github.com/rs/zerolog/log"
 	"gorm.io/gorm"
 	"tailscale.com/tailcfg"
 )
@@ -31,7 +33,10 @@ func (h *Headscale) CreateNamespace(name string) (*Namespace, error) {
 	}
 	n.Name = name
 	if err := h.db.Create(&n).Error; err != nil {
-		log.Printf("Could not create row: %s", err)
+		log.Error().
+			Str("func", "CreateNamespace").
+			Err(err).
+			Msg("Could not create row")
 		return nil, err
 	}
 	return &n, nil
@@ -103,6 +108,104 @@ func (h *Headscale) SetMachineNamespace(m *Machine, namespaceName string) error
 	return nil
 }
 
+// RequestMapUpdates signals the KV worker to update the maps for this namespace
+func (h *Headscale) RequestMapUpdates(namespaceID uint) error {
+	namespace := Namespace{}
+	if err := h.db.First(&namespace, namespaceID).Error; err != nil {
+		return err
+	}
+
+	v, err := h.getValue("namespaces_pending_updates")
+	if err != nil || v == "" {
+		err = h.setValue("namespaces_pending_updates", fmt.Sprintf(`["%s"]`, namespace.Name))
+		if err != nil {
+			return err
+		}
+		return nil
+	}
+	names := []string{}
+	err = json.Unmarshal([]byte(v), &names)
+	if err != nil {
+		err = h.setValue("namespaces_pending_updates", fmt.Sprintf(`["%s"]`, namespace.Name))
+		if err != nil {
+			return err
+		}
+		return nil
+	}
+
+	names = append(names, namespace.Name)
+	data, err := json.Marshal(names)
+	if err != nil {
+		log.Error().
+			Str("func", "RequestMapUpdates").
+			Err(err).
+			Msg("Could not marshal namespaces_pending_updates")
+		return err
+	}
+	return h.setValue("namespaces_pending_updates", string(data))
+}
+
+func (h *Headscale) checkForNamespacesPendingUpdates() {
+	v, err := h.getValue("namespaces_pending_updates")
+	if err != nil {
+		return
+	}
+	if v == "" {
+		return
+	}
+
+	names := []string{}
+	err = json.Unmarshal([]byte(v), &names)
+	if err != nil {
+		return
+	}
+	for _, name := range names {
+		log.Trace().
+			Str("func", "RequestMapUpdates").
+			Str("machine", name).
+			Msg("Sending updates to nodes in namespace")
+		machines, err := h.ListMachinesInNamespace(name)
+		if err != nil {
+			continue
+		}
+		for _, m := range *machines {
+			peers, _ := h.getPeers(m)
+			for _, p := range *peers {
+				pUp, ok := h.clientsPolling.Load(uint64(p.ID))
+				if ok {
+					log.Info().
+						Str("func", "checkForNamespacesPendingUpdates").
+						Str("machine", m.Name).
+						Str("peer", m.Name).
+						Str("address", p.Addresses[0].String()).
+						Msgf("Notifying peer %s (%s)", p.Name, p.Addresses[0])
+					pUp.(chan []byte) <- []byte{}
+				} else {
+					log.Info().
+						Str("func", "checkForNamespacesPendingUpdates").
+						Str("machine", m.Name).
+						Str("peer", m.Name).
+						Msgf("Peer %s does not appear to be polling", p.Name)
+				}
+			}
+		}
+	}
+	newV, err := h.getValue("namespaces_pending_updates")
+	if err != nil {
+		return
+	}
+	if v == newV { // only clear when no changes, so we notified everybody
+		err = h.setValue("namespaces_pending_updates", "")
+		if err != nil {
+			log.Error().
+				Str("func", "checkForNamespacesPendingUpdates").
+				Err(err).
+				Msg("Could not save to KV")
+			return
+		}
+	}
+}
+
 func (n *Namespace) toUser() *tailcfg.User {
 	u := tailcfg.User{
 		ID:            tailcfg.UserID(n.ID),

routes.go

@@ -52,8 +52,8 @@ func (h *Headscale) EnableNodeRoute(namespace string, nodeName string, routeStr
 			peers, _ := h.getPeers(*m)
 			h.pollMu.Lock()
 			for _, p := range *peers {
-				if pUp, ok := h.clientsPolling[uint64(p.ID)]; ok {
-					pUp <- []byte{}
+				if pUp, ok := h.clientsPolling.Load(uint64(p.ID)); ok {
+					pUp.(chan []byte) <- []byte{}
 				}
 			}
 			h.pollMu.Unlock()

utils.go

@@ -7,18 +7,12 @@ package headscale
 
 import (
 	"crypto/rand"
-	"encoding/binary"
 	"encoding/json"
-	"errors"
 	"fmt"
 	"io"
-	"net"
-	"time"
-
-	mathrand "math/rand"
 
 	"golang.org/x/crypto/nacl/box"
-	"gorm.io/gorm"
+	"inet.af/netaddr"
 	"tailscale.com/types/wgkey"
 )
 
@@ -77,47 +71,71 @@ func encodeMsg(b []byte, pubKey *wgkey.Key, privKey *wgkey.Private) ([]byte, err
 	return msg, nil
 }
 
-func (h *Headscale) getAvailableIP() (*net.IP, error) {
-	i := 0
+func (h *Headscale) getAvailableIP() (*netaddr.IP, error) {
+	ipPrefix := h.cfg.IPPrefix
+
+	usedIps, err := h.getUsedIPs()
+	if err != nil {
+		return nil, err
+	}
+
+	// Get the first IP in our prefix
+	ip := ipPrefix.IP()
+
 	for {
-		ip, err := getRandomIP()
-		if err != nil {
-			return nil, err
+		if !ipPrefix.Contains(ip) {
+			return nil, fmt.Errorf("could not find any suitable IP in %s", ipPrefix)
 		}
-		m := Machine{}
-		if result := h.db.First(&m, "ip_address = ?", ip.String()); errors.Is(result.Error, gorm.ErrRecordNotFound) {
-			return ip, nil
+
+		// Some OS (including Linux) does not like when IPs ends with 0 or 255, which
+		// is typically called network or broadcast. Lets avoid them and continue
+		// to look when we get one of those traditionally reserved IPs.
+		ipRaw := ip.As4()
+		if ipRaw[3] == 0 || ipRaw[3] == 255 {
+			ip = ip.Next()
+			continue
 		}
-		i++
-		if i == 100 { // really random number
-			break
+
+		if ip.IsZero() &&
+			ip.IsLoopback() {
+
+			ip = ip.Next()
+			continue
 		}
+
+		if !containsIPs(usedIps, ip) {
+			return &ip, nil
+		}
+
+		ip = ip.Next()
 	}
-	return nil, errors.New("Could not find an available IP address in 100.64.0.0/10")
 }
 
-func getRandomIP() (*net.IP, error) {
-	mathrand.Seed(time.Now().Unix())
-	ipo, ipnet, err := net.ParseCIDR("100.64.0.0/10")
-	if err == nil {
-		ip := ipo.To4()
-		// fmt.Println("In Randomize IPAddr: IP ", ip, " IPNET: ", ipnet)
-		// fmt.Println("Final address is ", ip)
-		// fmt.Println("Broadcast address is ", ipb)
-		// fmt.Println("Network address is ", ipn)
-		r := mathrand.Uint32()
-		ipRaw := make([]byte, 4)
-		binary.LittleEndian.PutUint32(ipRaw, r)
-		// ipRaw[3] = 254
-		// fmt.Println("ipRaw is ", ipRaw)
-		for i, v := range ipRaw {
-			// fmt.Println("IP Before: ", ip[i], " v is ", v, " Mask is: ", ipnet.Mask[i])
-			ip[i] = ip[i] + (v &^ ipnet.Mask[i])
-			// fmt.Println("IP After: ", ip[i])
+func (h *Headscale) getUsedIPs() ([]netaddr.IP, error) {
+	var addresses []string
+	h.db.Model(&Machine{}).Pluck("ip_address", &addresses)
+
+	ips := make([]netaddr.IP, len(addresses))
+	for index, addr := range addresses {
+		if addr != "" {
+			ip, err := netaddr.ParseIP(addr)
+			if err != nil {
+				return nil, fmt.Errorf("failed to parse ip from database, %w", err)
+			}
+
+			ips[index] = ip
 		}
-		// fmt.Println("FINAL IP: ", ip.String())
-		return &ip, nil
 	}
 
-	return nil, err
+	return ips, nil
+}
+
+func containsIPs(ips []netaddr.IP, ip netaddr.IP) bool {
+	for _, v := range ips {
+		if v == ip {
+			return true
+		}
+	}
+
+	return false
 }

utils_test.go

@@ -0,0 +1,155 @@
+package headscale
+
+import (
+	"gopkg.in/check.v1"
+	"inet.af/netaddr"
+)
+
+func (s *Suite) TestGetAvailableIp(c *check.C) {
+	ip, err := h.getAvailableIP()
+
+	c.Assert(err, check.IsNil)
+
+	expected := netaddr.MustParseIP("10.27.0.1")
+
+	c.Assert(ip.String(), check.Equals, expected.String())
+}
+
+func (s *Suite) TestGetUsedIps(c *check.C) {
+	ip, err := h.getAvailableIP()
+	c.Assert(err, check.IsNil)
+
+	n, err := h.CreateNamespace("test_ip")
+	c.Assert(err, check.IsNil)
+
+	pak, err := h.CreatePreAuthKey(n.Name, false, false, nil)
+	c.Assert(err, check.IsNil)
+
+	_, err = h.GetMachine("test", "testmachine")
+	c.Assert(err, check.NotNil)
+
+	m := Machine{
+		ID:             0,
+		MachineKey:     "foo",
+		NodeKey:        "bar",
+		DiscoKey:       "faa",
+		Name:           "testmachine",
+		NamespaceID:    n.ID,
+		Registered:     true,
+		RegisterMethod: "authKey",
+		AuthKeyID:      uint(pak.ID),
+		IPAddress:      ip.String(),
+	}
+	h.db.Save(&m)
+
+	ips, err := h.getUsedIPs()
+
+	c.Assert(err, check.IsNil)
+
+	expected := netaddr.MustParseIP("10.27.0.1")
+
+	c.Assert(ips[0], check.Equals, expected)
+
+	m1, err := h.GetMachineByID(0)
+	c.Assert(err, check.IsNil)
+
+	c.Assert(m1.IPAddress, check.Equals, expected.String())
+}
+
+func (s *Suite) TestGetMultiIp(c *check.C) {
+	n, err := h.CreateNamespace("test-ip-multi")
+	c.Assert(err, check.IsNil)
+
+	for i := 1; i <= 350; i++ {
+		ip, err := h.getAvailableIP()
+		c.Assert(err, check.IsNil)
+
+		pak, err := h.CreatePreAuthKey(n.Name, false, false, nil)
+		c.Assert(err, check.IsNil)
+
+		_, err = h.GetMachine("test", "testmachine")
+		c.Assert(err, check.NotNil)
+
+		m := Machine{
+			ID:             uint64(i),
+			MachineKey:     "foo",
+			NodeKey:        "bar",
+			DiscoKey:       "faa",
+			Name:           "testmachine",
+			NamespaceID:    n.ID,
+			Registered:     true,
+			RegisterMethod: "authKey",
+			AuthKeyID:      uint(pak.ID),
+			IPAddress:      ip.String(),
+		}
+		h.db.Save(&m)
+	}
+
+	ips, err := h.getUsedIPs()
+
+	c.Assert(err, check.IsNil)
+
+	c.Assert(len(ips), check.Equals, 350)
+
+	c.Assert(ips[0], check.Equals, netaddr.MustParseIP("10.27.0.1"))
+	c.Assert(ips[9], check.Equals, netaddr.MustParseIP("10.27.0.10"))
+	c.Assert(ips[300], check.Equals, netaddr.MustParseIP("10.27.1.47"))
+
+	// Check that we can read back the IPs
+	m1, err := h.GetMachineByID(1)
+	c.Assert(err, check.IsNil)
+	c.Assert(m1.IPAddress, check.Equals, netaddr.MustParseIP("10.27.0.1").String())
+
+	m50, err := h.GetMachineByID(50)
+	c.Assert(err, check.IsNil)
+	c.Assert(m50.IPAddress, check.Equals, netaddr.MustParseIP("10.27.0.50").String())
+
+	expectedNextIP := netaddr.MustParseIP("10.27.1.97")
+	nextIP, err := h.getAvailableIP()
+	c.Assert(err, check.IsNil)
+
+	c.Assert(nextIP.String(), check.Equals, expectedNextIP.String())
+
+	// If we call get Available again, we should receive
+	// the same IP, as it has not been reserved.
+	nextIP2, err := h.getAvailableIP()
+	c.Assert(err, check.IsNil)
+
+	c.Assert(nextIP2.String(), check.Equals, expectedNextIP.String())
+}
+
+func (s *Suite) TestGetAvailableIpMachineWithoutIP(c *check.C) {
+	ip, err := h.getAvailableIP()
+	c.Assert(err, check.IsNil)
+
+	expected := netaddr.MustParseIP("10.27.0.1")
+
+	c.Assert(ip.String(), check.Equals, expected.String())
+
+	n, err := h.CreateNamespace("test_ip")
+	c.Assert(err, check.IsNil)
+
+	pak, err := h.CreatePreAuthKey(n.Name, false, false, nil)
+	c.Assert(err, check.IsNil)
+
+	_, err = h.GetMachine("test", "testmachine")
+	c.Assert(err, check.NotNil)
+
+	m := Machine{
+		ID:             0,
+		MachineKey:     "foo",
+		NodeKey:        "bar",
+		DiscoKey:       "faa",
+		Name:           "testmachine",
+		NamespaceID:    n.ID,
+		Registered:     true,
+		RegisterMethod: "authKey",
+		AuthKeyID:      uint(pak.ID),
+	}
+	h.db.Save(&m)
+
+	ip2, err := h.getAvailableIP()
+	c.Assert(err, check.IsNil)
+
+	c.Assert(ip2.String(), check.Equals, expected.String())
+}