feat: bootstrap central config from node config dist URL on first run

cmd/run.go

@@ -46,11 +46,39 @@ var runCmd = &cobra.Command{
 		var centralCfg state.CentralCfg
 		file, err := os.ReadFile(centralPath)
 		if err != nil {
-			panic(err)
-		}
-		err = yaml.Unmarshal(file, &centralCfg)
-		if err != nil {
-			panic(err)
+			if !os.IsNotExist(err) {
+				panic(err)
+			}
+			var nodeCfg state.LocalCfg
+			file, err = os.ReadFile(nodePath)
+			if err != nil {
+				panic(err)
+			}
+			err = yaml.Unmarshal(file, &nodeCfg)
+			if err != nil {
+				panic(err)
+			}
+			if nodeCfg.Dist == nil {
+				panic("central.yaml not found and node.yaml has no dist config")
+			}
+			cfg, err := core.FetchConfig(nodeCfg.Dist.Url, nodeCfg.Dist.Key)
+			if err != nil {
+				panic(err)
+			}
+			bytes, err := yaml.Marshal(cfg)
+			if err != nil {
+				panic(err)
+			}
+			err = os.WriteFile(centralPath, bytes, 0700)
+			if err != nil {
+				panic(err)
+			}
+			centralCfg = *cfg
+		} else {
+			err = yaml.Unmarshal(file, &centralCfg)
+			if err != nil {
+				panic(err)
+			}
 		}
 
 		var nodeCfg state.LocalCfg

core/nylon.go

@@ -74,8 +74,8 @@ func (n *Nylon) Init(s *state.State) error {
 	}
 
 	// check for central config updates
-	if s.Dist != nil {
-		for _, repo := range s.Dist.Repos {
+	if s.CentralCfg.Dist != nil {
+		for _, repo := range s.CentralCfg.Dist.Repos {
 			s.Log.Info("config source", "repo", repo)
 		}
 		s.Env.RepeatTask(checkForConfigUpdates, state.CentralUpdateDelay)

core/nylon_distribution.go

@@ -12,48 +12,58 @@ import (
 	"gopkg.in/yaml.v3"
 )
 
+// fetches and unbundles central config from url
+func FetchConfig(repoStr string, key state.NyPublicKey) (*state.CentralCfg, error) {
+	repo, err := url.Parse(repoStr)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse repo URL %s: %w", repoStr, err)
+	}
+	cfgBody := make([]byte, 0)
+
+	if repo.Scheme == "file" {
+		file, err := os.ReadFile(repo.Opaque)
+		if err != nil {
+			return nil, fmt.Errorf("failed to read file %s: %w", repo.Opaque, err)
+		}
+		cfgBody = file
+	} else if repo.Scheme == "http" || repo.Scheme == "https" {
+		res, err := http.Get(repo.String())
+		if err != nil {
+			return nil, fmt.Errorf("failed to fetch %s: %w", repo.String(), err)
+		}
+		cfgBody, err = io.ReadAll(res.Body)
+		if err != nil {
+			res.Body.Close()
+			return nil, fmt.Errorf("failed to read response from %s: %w", repo.String(), err)
+		}
+		err = res.Body.Close()
+		if err != nil {
+			return nil, fmt.Errorf("failed to close response from %s: %w", repo.String(), err)
+		}
+	}
+
+	config, err := state.UnbundleConfig(string(cfgBody), key)
+	if err != nil {
+		return nil, fmt.Errorf("failed to unbundle config from %s: %w", repoStr, err)
+	}
+	return config, nil
+}
+
 // responsible for central config distribution
 func checkForConfigUpdates(s *state.State) error {
-	if s.Dist == nil {
+	if s.CentralCfg.Dist == nil {
 		return errors.New("nylon is not configured for automatic config distribution")
 	}
-	for _, repoStr := range s.Dist.Repos {
-		repo, err := url.Parse(repoStr)
-		if err != nil {
-			return err
-		}
+	for _, repoStr := range s.CentralCfg.Dist.Repos {
 		e := s.Env
-		go func() {
+		go func(repo string) {
 			err := func() error {
-				cfgBody := make([]byte, 0)
-
-				if repo.Scheme == "file" {
-					file, err := os.ReadFile(repo.Opaque)
-					if err != nil {
-						return err
-					}
-					cfgBody = file
-				} else if repo.Scheme == "http" || repo.Scheme == "https" {
-					res, err := http.Get(repo.String())
-					if err != nil {
-						return err
-					}
-					cfgBody, err = io.ReadAll(res.Body)
-					if err != nil {
-						return err
-					}
-					err = res.Body.Close()
-					if err != nil {
-						return err
-					}
-				}
-
-				config, err := state.UnbundleConfig(string(cfgBody), e.Dist.Key)
+				config, err := FetchConfig(repo, e.CentralCfg.Dist.Key)
 				if err != nil {
 					return err
 				}
 				if config.Timestamp > e.Timestamp && !s.Updating.Swap(true) {
-					e.Log.Info("Found a new config update in repo", "repo", repo.String())
+					e.Log.Info("Found a new config update in repo", "repo", repo)
 					bytes, err := yaml.Marshal(config)
 					if err != nil {
 						e.Log.Error("Error marshalling new config", "err", err.Error())
@@ -69,14 +79,14 @@ func checkForConfigUpdates(s *state.State) error {
 				err:
 					s.Updating.Store(false)
 				} else if state.DBG_log_repo_updates {
-					e.Log.Debug(fmt.Sprintf("found old update bundle at %s, skipping", repo.String()))
+					e.Log.Debug(fmt.Sprintf("found old update bundle at %s, skipping", repo))
 				}
 				return nil
 			}()
 			if err != nil && state.DBG_log_repo_updates {
 				e.Log.Error("Error updating config", "err", err.Error())
 			}
-		}()
+		}(repoStr)
 	}
 	return nil
 }

example/sample-node.yaml

@@ -5,4 +5,7 @@ nonetconfigure: false # Default: false - If enabled, Nylon will not configure th
 usesystemrouting: false # Default: false - if enabled, Nylon will use the system route table to forward packets
 logpath: "" # Default: "" - If set, Nylon will log to this file
 interfacename: "" # Default: "" - If set, Nylon will use this interface name instead of the default "nylon" or utunx on macOS
-disablerouting: false # Default: false - If true, Nylon will not route traffic through this node
+disablerouting: false # Default: false - If true, Nylon will not route traffic through this node
+dist: # Optional: If set, Nylon will bootstrap central.yaml from this URL if it does not exist already
+  url: https://static.example.com/network1.nybundle
+  key: 7PaN6DmAayz4KnDnsXSXJH+Oy0TFGeoM4FEbQfLriVY=

state/config.go

@@ -29,6 +29,11 @@ type DistributionCfg struct {
 	Repos []string
 }
 
+type LocalDistributionCfg struct {
+	Key NyPublicKey
+	Url string
+}
+
 type CentralCfg struct {
 	Dist      *DistributionCfg `yaml:",omitempty"`
 	Routers   []RouterCfg
@@ -65,6 +70,7 @@ type LocalCfg struct {
 	Id  NodeId
 	// Address that the data plane can be accessed by
 	Port             uint16
+	Dist             *LocalDistributionCfg `yaml:",omitempty"`
 	DisableRouting   bool
 	UseSystemRouting bool
 	NoNetConfigure   bool `yaml:",omitempty"`

state/validation.go

@@ -55,6 +55,12 @@ func NodeConfigValidator(node *LocalCfg) error {
 			return fmt.Errorf("interface name is invalid: %v", err)
 		}
 	}
+	if node.Dist != nil {
+		_, err := url.Parse(node.Dist.Url)
+		if err != nil {
+			return err
+		}
+	}
 	return nil
 }