Merge pull request 'zones: improve scan validations' (#11)

Reviewed-on: #11

pkg/zones/errors.go

@@ -0,0 +1,16 @@
+package zones
+
+import "errors"
+
+var (
+	// ErrInvalidName indicates the name isn't valid
+	ErrInvalidName = errors.New("invalid name")
+
+	// ErrUnknownNode indicates there is a reference to a node
+	// we don't have on the tree
+	ErrUnknownNode = errors.New("node does not exist")
+
+	// ErrInvalidNode indicates the nodes can't be used for
+	// the intended purpose
+	ErrInvalidNode = errors.New("invalid node")
+)

pkg/zones/machine_rings.go

@@ -2,6 +2,7 @@ package zones
 
 import (
 	"bytes"
+	"errors"
 	"fmt"
 	"os"
 
@@ -135,7 +136,11 @@ func (m *Machine) applyWireguardConfig(ring int, wg *wireguard.Config) error {
 	}
 
 	for _, peer := range wg.Peer {
-		if err := m.applyWireguardPeerConfig(ring, peer); err != nil {
+		err := m.applyWireguardPeerConfig(ring, peer)
+		switch {
+		case errors.Is(err, ErrUnknownNode):
+			// ignore unknown peers
+		case err != nil:
 			err = core.Wrapf(err, "%s: wg%v:%s", m.Name, ring, addr)
 			return err
 		}
@@ -183,8 +188,10 @@ func (m *Machine) applyWireguardPeerConfig(ring int, pc wireguard.PeerConfig) er
 	switch {
 	case !found:
 		// unknown
+		return core.Wrap(ErrUnknownNode, pc.Endpoint.Host)
 	case ring == 1 && m.zone != peer.zone:
 		// invalid zone
+		return core.Wrap(ErrInvalidNode, peer.Name)
 	default:
 		// apply RingInfo
 		ri := &RingInfo{
@@ -197,8 +204,6 @@ func (m *Machine) applyWireguardPeerConfig(ring int, pc wireguard.PeerConfig) er
 
 		return peer.applyRingInfo(ring, ri)
 	}
-
-	return fmt.Errorf("%q: invalid peer endpoint", pc.Endpoint.Host)
 }
 
 func (m *Machine) applyZoneNodeID(zoneID, nodeID int) error {

pkg/zones/machine_scan.go

@@ -4,7 +4,10 @@ import (
 	"context"
 	"net/netip"
 	"strconv"
+	"strings"
 	"time"
+
+	"darvaza.org/core"
 )
 
 // LookupNetIP uses the DNS Resolver to get the public addresses associated
@@ -30,21 +33,32 @@ func (m *Machine) UpdatePublicAddresses() error {
 
 func (m *Machine) init() error {
 	if err := m.setID(); err != nil {
-		return err
+		return core.Wrap(err, m.Name)
 	}
 
 	for i := 0; i < RingsCount; i++ {
 		if err := m.tryReadWireguardKeys(i); err != nil {
-			return err
+			return core.Wrap(err, m.Name)
 		}
 	}
+
 	return nil
 }
 
 func (m *Machine) setID() error {
 	zoneName := m.zone.Name
-	suffix := m.Name[len(zoneName)+1:]
 
+	l := len(zoneName)
+	switch {
+	case len(m.Name) < l+2:
+		return ErrInvalidName
+	case !strings.HasPrefix(m.Name, zoneName):
+		return ErrInvalidName
+	case m.Name[l] != '-':
+		return ErrInvalidName
+	}
+
+	suffix := m.Name[l+1:]
 	id, err := strconv.ParseInt(suffix, 10, 8)
 	if err != nil {
 		return err

pkg/zones/scan.go

@@ -3,6 +3,8 @@ package zones
 import (
 	"io/fs"
 	"sort"
+
+	"darvaza.org/core"
 )
 
 func (m *Zones) scan(opts *ScanOptions) error {
@@ -31,23 +33,32 @@ func (m *Zones) scanDirectory(_ *ScanOptions) error {
 
 	for _, e := range entries {
 		if e.IsDir() {
-			z := &Zone{
-				zones:  m,
-				logger: m,
-				Name:   e.Name(),
-			}
-
-			if err := z.scan(); err != nil {
-				return err
+			z, err := m.newZone(e.Name())
+			switch {
+			case err != nil:
+				return core.Wrap(err, e.Name())
+			case z.Machines.Len() > 0:
+				m.Zones = append(m.Zones, z)
 			}
-
-			m.Zones = append(m.Zones, z)
 		}
 	}
 
 	return nil
 }
 
+func (m *Zones) newZone(name string) (*Zone, error) {
+	z := &Zone{
+		zones:  m,
+		logger: m,
+		Name:   name,
+	}
+
+	if err := z.scan(); err != nil {
+		return nil, err
+	}
+	return z, nil
+}
+
 func (m *Zones) scanMachines(opts *ScanOptions) error {
 	var err error
 	m.ForEachMachine(func(p *Machine) bool {