[management, client] Add API to change the network range (#4177)

client/iface/wgproxy/bind/proxy.go

@@ -171,7 +171,7 @@ func fakeAddress(peerAddress *net.UDPAddr) (*netip.AddrPort, error) {
 
 	fakeIP, err := netip.ParseAddr(fmt.Sprintf("127.1.%s.%s", octets[2], octets[3]))
 	if err != nil {
-		return nil, fmt.Errorf("failed to parse new IP: %w", err)
+		return nil, fmt.Errorf("parse new IP: %w", err)
 	}
 
 	netipAddr := netip.AddrPortFrom(fakeIP, uint16(peerAddress.Port))

client/iface/wgproxy/ebpf/wrapper.go

@@ -95,7 +95,7 @@ func (e *ProxyWrapper) CloseConn() error {
 	e.closeListener.SetCloseListener(nil)
 
 	if err := e.remoteConn.Close(); err != nil && !errors.Is(err, net.ErrClosed) {
-		return fmt.Errorf("failed to close remote conn: %w", err)
+		return fmt.Errorf("close remote conn: %w", err)
 	}
 	return nil
 }

client/internal/engine.go

@@ -861,15 +861,10 @@ func (e *Engine) updateConfig(conf *mgmProto.PeerConfig) error {
 		return errors.New("wireguard interface is not initialized")
 	}
 
+	// Cannot update the IP address without restarting the engine because
+	// the firewall, route manager, and other components cache the old address
 	if e.wgInterface.Address().String() != conf.Address {
-		oldAddr := e.wgInterface.Address().String()
-		log.Debugf("updating peer address from %s to %s", oldAddr, conf.Address)
-		err := e.wgInterface.UpdateAddr(conf.Address)
-		if err != nil {
-			return err
-		}
-		e.config.WgAddr = conf.Address
-		log.Infof("updated peer address from %s to %s", oldAddr, conf.Address)
+		log.Infof("peer IP address has changed from %s to %s", e.wgInterface.Address().String(), conf.Address)
 	}
 
 	if conf.GetSshConfig() != nil {
@@ -880,7 +875,7 @@ func (e *Engine) updateConfig(conf *mgmProto.PeerConfig) error {
 	}
 
 	state := e.statusRecorder.GetLocalPeerState()
-	state.IP = e.config.WgAddr
+	state.IP = e.wgInterface.Address().String()
 	state.PubKey = e.config.WgPrivateKey.PublicKey().String()
 	state.KernelInterface = device.WireGuardModuleIsLoaded()
 	state.FQDN = conf.GetFqdn()

management/cmd/management.go

@@ -142,7 +142,7 @@ var (
 
 			err := handleRebrand(cmd)
 			if err != nil {
-				return fmt.Errorf("failed to migrate files %v", err)
+				return fmt.Errorf("migrate files %v", err)
 			}
 
 			if _, err = os.Stat(config.Datadir); os.IsNotExist(err) {
@@ -184,7 +184,7 @@ var (
 			}
 			eventStore, key, err := integrations.InitEventStore(ctx, config.Datadir, config.DataStoreEncryptionKey, integrationMetrics)
 			if err != nil {
-				return fmt.Errorf("failed to initialize database: %s", err)
+				return fmt.Errorf("initialize database: %s", err)
 			}
 
 			if config.DataStoreEncryptionKey != key {
@@ -192,7 +192,7 @@ var (
 				config.DataStoreEncryptionKey = key
 				err := updateMgmtConfig(ctx, types.MgmtConfigPath, config)
 				if err != nil {
-					return fmt.Errorf("failed to write out store encryption key: %s", err)
+					return fmt.Errorf("write out store encryption key: %s", err)
 				}
 			}
 
@@ -205,7 +205,7 @@ var (
 
 			integratedPeerValidator, err := integrations.NewIntegratedValidator(ctx, eventStore)
 			if err != nil {
-				return fmt.Errorf("failed to initialize integrated peer validator: %v", err)
+				return fmt.Errorf("initialize integrated peer validator: %v", err)
 			}
 
 			permissionsManager := integrations.InitPermissionsManager(store)
@@ -217,7 +217,7 @@ var (
 			accountManager, err := server.BuildManager(ctx, store, peersUpdateManager, idpManager, mgmtSingleAccModeDomain,
 				dnsDomain, eventStore, geo, userDeleteFromIDPEnabled, integratedPeerValidator, appMetrics, proxyController, settingsManager, permissionsManager, config.DisableDefaultPolicy)
 			if err != nil {
-				return fmt.Errorf("failed to build default manager: %v", err)
+				return fmt.Errorf("build default manager: %v", err)
 			}
 
 			secretsManager := server.NewTimeBasedAuthSecretsManager(peersUpdateManager, config.TURNConfig, config.Relay, settingsManager)

management/server/account.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"math/rand"
 	"net"
+	"net/netip"
 	"os"
 	"reflect"
 	"regexp"
@@ -324,6 +325,13 @@ func (am *DefaultAccountManager) UpdateAccountSettings(ctx context.Context, acco
 			return err
 		}
 
+		if oldSettings.NetworkRange != newSettings.NetworkRange {
+			if err = am.reallocateAccountPeerIPs(ctx, transaction, accountID, newSettings.NetworkRange); err != nil {
+				return err
+			}
+			updateAccountPeers = true
+		}
+
 		if oldSettings.RoutingPeerDNSResolutionEnabled != newSettings.RoutingPeerDNSResolutionEnabled ||
 			oldSettings.LazyConnectionEnabled != newSettings.LazyConnectionEnabled ||
 			oldSettings.DNSDomain != newSettings.DNSDomain {
@@ -362,7 +370,18 @@ func (am *DefaultAccountManager) UpdateAccountSettings(ctx context.Context, acco
 		return nil, err
 	}
 	if oldSettings.DNSDomain != newSettings.DNSDomain {
-		am.StoreEvent(ctx, userID, accountID, accountID, activity.AccountDNSDomainUpdated, nil)
+		eventMeta := map[string]any{
+			"old_dns_domain": oldSettings.DNSDomain,
+			"new_dns_domain": newSettings.DNSDomain,
+		}
+		am.StoreEvent(ctx, userID, accountID, accountID, activity.AccountDNSDomainUpdated, eventMeta)
+	}
+	if oldSettings.NetworkRange != newSettings.NetworkRange {
+		eventMeta := map[string]any{
+			"old_network_range": oldSettings.NetworkRange.String(),
+			"new_network_range": newSettings.NetworkRange.String(),
+		}
+		am.StoreEvent(ctx, userID, accountID, accountID, activity.AccountNetworkRangeUpdated, eventMeta)
 	}
 
 	if updateAccountPeers || extraSettingsChanged || groupChangesAffectPeers {
@@ -2018,3 +2037,154 @@ func propagateUserGroupMemberships(ctx context.Context, transaction store.Store,
 
 	return len(updatedGroups) > 0, peersAffected, nil
 }
+
+// reallocateAccountPeerIPs re-allocates all peer IPs when the network range changes
+func (am *DefaultAccountManager) reallocateAccountPeerIPs(ctx context.Context, transaction store.Store, accountID string, newNetworkRange netip.Prefix) error {
+	if !newNetworkRange.IsValid() {
+		return nil
+	}
+
+	newIPNet := net.IPNet{
+		IP:   newNetworkRange.Masked().Addr().AsSlice(),
+		Mask: net.CIDRMask(newNetworkRange.Bits(), newNetworkRange.Addr().BitLen()),
+	}
+
+	account, err := transaction.GetAccount(ctx, accountID)
+	if err != nil {
+		return err
+	}
+
+	account.Network.Net = newIPNet
+
+	peers, err := transaction.GetAccountPeers(ctx, store.LockingStrengthShare, accountID, "", "")
+	if err != nil {
+		return err
+	}
+
+	var takenIPs []net.IP
+
+	for _, peer := range peers {
+		newIP, err := types.AllocatePeerIP(newIPNet, takenIPs)
+		if err != nil {
+			return status.Errorf(status.Internal, "allocate IP for peer %s: %v", peer.ID, err)
+		}
+
+		log.WithContext(ctx).Infof("reallocating peer %s IP from %s to %s due to network range change",
+			peer.ID, peer.IP.String(), newIP.String())
+
+		peer.IP = newIP
+		takenIPs = append(takenIPs, newIP)
+	}
+
+	if err = transaction.SaveAccount(ctx, account); err != nil {
+		return err
+	}
+
+	for _, peer := range peers {
+		if err = transaction.SavePeer(ctx, store.LockingStrengthUpdate, accountID, peer); err != nil {
+			return status.Errorf(status.Internal, "save updated peer %s: %v", peer.ID, err)
+		}
+	}
+
+	log.WithContext(ctx).Infof("successfully re-allocated IPs for %d peers in account %s to network range %s",
+		len(peers), accountID, newNetworkRange.String())
+
+	return nil
+}
+
+func (am *DefaultAccountManager) validateIPForUpdate(account *types.Account, peers []*nbpeer.Peer, peerID string, newIP netip.Addr) error {
+	if !account.Network.Net.Contains(newIP.AsSlice()) {
+		return status.Errorf(status.InvalidArgument, "IP %s is not within the account network range %s", newIP.String(), account.Network.Net.String())
+	}
+
+	for _, peer := range peers {
+		if peer.ID != peerID && peer.IP.Equal(newIP.AsSlice()) {
+			return status.Errorf(status.InvalidArgument, "IP %s is already assigned to peer %s", newIP.String(), peer.ID)
+		}
+	}
+	return nil
+}
+
+func (am *DefaultAccountManager) UpdatePeerIP(ctx context.Context, accountID, userID, peerID string, newIP netip.Addr) error {
+	unlock := am.Store.AcquireWriteLockByUID(ctx, accountID)
+	defer unlock()
+
+	allowed, err := am.permissionsManager.ValidateUserPermissions(ctx, accountID, userID, modules.Peers, operations.Update)
+	if err != nil {
+		return fmt.Errorf("validate user permissions: %w", err)
+	}
+	if !allowed {
+		return status.NewPermissionDeniedError()
+	}
+
+	updateNetworkMap, err := am.updatePeerIPInTransaction(ctx, accountID, userID, peerID, newIP)
+	if err != nil {
+		return fmt.Errorf("update peer IP transaction: %w", err)
+	}
+
+	if updateNetworkMap {
+		am.BufferUpdateAccountPeers(ctx, accountID)
+	}
+	return nil
+}
+
+func (am *DefaultAccountManager) updatePeerIPInTransaction(ctx context.Context, accountID, userID, peerID string, newIP netip.Addr) (bool, error) {
+	var updateNetworkMap bool
+	err := am.Store.ExecuteInTransaction(ctx, func(transaction store.Store) error {
+		account, err := transaction.GetAccount(ctx, accountID)
+		if err != nil {
+			return fmt.Errorf("get account: %w", err)
+		}
+
+		existingPeer, err := transaction.GetPeerByID(ctx, store.LockingStrengthShare, accountID, peerID)
+		if err != nil {
+			return fmt.Errorf("get peer: %w", err)
+		}
+
+		if existingPeer.IP.Equal(newIP.AsSlice()) {
+			return nil
+		}
+
+		peers, err := transaction.GetAccountPeers(ctx, store.LockingStrengthShare, accountID, "", "")
+		if err != nil {
+			return fmt.Errorf("get account peers: %w", err)
+		}
+
+		if err := am.validateIPForUpdate(account, peers, peerID, newIP); err != nil {
+			return err
+		}
+
+		if err := am.savePeerIPUpdate(ctx, transaction, accountID, userID, existingPeer, newIP); err != nil {
+			return err
+		}
+
+		updateNetworkMap = true
+		return nil
+	})
+	return updateNetworkMap, err
+}
+
+func (am *DefaultAccountManager) savePeerIPUpdate(ctx context.Context, transaction store.Store, accountID, userID string, peer *nbpeer.Peer, newIP netip.Addr) error {
+	log.WithContext(ctx).Infof("updating peer %s IP from %s to %s", peer.ID, peer.IP, newIP)
+
+	settings, err := transaction.GetAccountSettings(ctx, store.LockingStrengthShare, accountID)
+	if err != nil {
+		return fmt.Errorf("get account settings: %w", err)
+	}
+	dnsDomain := am.GetDNSDomain(settings)
+
+	eventMeta := peer.EventMeta(dnsDomain)
+	oldIP := peer.IP.String()
+
+	peer.IP = newIP.AsSlice()
+	err = transaction.SavePeer(ctx, store.LockingStrengthUpdate, accountID, peer)
+	if err != nil {
+		return fmt.Errorf("save peer: %w", err)
+	}
+
+	eventMeta["old_ip"] = oldIP
+	eventMeta["ip"] = newIP.String()
+	am.StoreEvent(ctx, userID, peer.ID, accountID, activity.PeerIPUpdated, eventMeta)
+
+	return nil
+}

management/server/account/manager.go

@@ -51,6 +51,7 @@ type Manager interface {
 	MarkPeerConnected(ctx context.Context, peerKey string, connected bool, realIP net.IP, accountID string) error
 	DeletePeer(ctx context.Context, accountID, peerID, userID string) error
 	UpdatePeer(ctx context.Context, accountID, userID string, peer *nbpeer.Peer) (*nbpeer.Peer, error)
+	UpdatePeerIP(ctx context.Context, accountID, userID, peerID string, newIP netip.Addr) error
 	GetNetworkMap(ctx context.Context, peerID string) (*types.NetworkMap, error)
 	GetPeerNetwork(ctx context.Context, peerID string) (*types.Network, error)
 	AddPeer(ctx context.Context, setupKey, userID string, peer *nbpeer.Peer) (*nbpeer.Peer, *types.NetworkMap, []*posture.Checks, error)

management/server/account_test.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"io"
 	"net"
+	"net/netip"
 	"os"
 	"reflect"
 	"strconv"
@@ -3522,3 +3523,70 @@ func TestDefaultAccountManager_UpdateAccountOnboarding(t *testing.T) {
 		require.NoError(t, err)
 	})
 }
+
+func TestDefaultAccountManager_UpdatePeerIP(t *testing.T) {
+	manager, err := createManager(t)
+	require.NoError(t, err, "unable to create account manager")
+
+	accountID, err := manager.GetAccountIDByUserID(context.Background(), userID, "")
+	require.NoError(t, err, "unable to create an account")
+
+	key1, err := wgtypes.GenerateKey()
+	require.NoError(t, err, "unable to generate WireGuard key")
+	key2, err := wgtypes.GenerateKey()
+	require.NoError(t, err, "unable to generate WireGuard key")
+
+	peer1, _, _, err := manager.AddPeer(context.Background(), "", userID, &nbpeer.Peer{
+		Key:  key1.PublicKey().String(),
+		Meta: nbpeer.PeerSystemMeta{Hostname: "test-peer-1"},
+	})
+	require.NoError(t, err, "unable to add peer1")
+
+	peer2, _, _, err := manager.AddPeer(context.Background(), "", userID, &nbpeer.Peer{
+		Key:  key2.PublicKey().String(),
+		Meta: nbpeer.PeerSystemMeta{Hostname: "test-peer-2"},
+	})
+	require.NoError(t, err, "unable to add peer2")
+
+	t.Run("update peer IP successfully", func(t *testing.T) {
+		account, err := manager.Store.GetAccount(context.Background(), accountID)
+		require.NoError(t, err, "unable to get account")
+
+		newIP, err := types.AllocatePeerIP(account.Network.Net, []net.IP{peer1.IP, peer2.IP})
+		require.NoError(t, err, "unable to allocate new IP")
+
+		newAddr := netip.MustParseAddr(newIP.String())
+		err = manager.UpdatePeerIP(context.Background(), accountID, userID, peer1.ID, newAddr)
+		require.NoError(t, err, "unable to update peer IP")
+
+		updatedPeer, err := manager.GetPeer(context.Background(), accountID, peer1.ID, userID)
+		require.NoError(t, err, "unable to get updated peer")
+		assert.Equal(t, newIP.String(), updatedPeer.IP.String(), "peer IP should be updated")
+	})
+
+	t.Run("update peer IP with same IP should be no-op", func(t *testing.T) {
+		currentAddr := netip.MustParseAddr(peer1.IP.String())
+		err := manager.UpdatePeerIP(context.Background(), accountID, userID, peer1.ID, currentAddr)
+		require.NoError(t, err, "updating with same IP should not error")
+	})
+
+	t.Run("update peer IP with collision should fail", func(t *testing.T) {
+		peer2Addr := netip.MustParseAddr(peer2.IP.String())
+		err := manager.UpdatePeerIP(context.Background(), accountID, userID, peer1.ID, peer2Addr)
+		require.Error(t, err, "should fail when IP is already assigned")
+		assert.Contains(t, err.Error(), "already assigned", "error should mention IP collision")
+	})
+
+	t.Run("update peer IP outside network range should fail", func(t *testing.T) {
+		invalidAddr := netip.MustParseAddr("192.168.1.100")
+		err := manager.UpdatePeerIP(context.Background(), accountID, userID, peer1.ID, invalidAddr)
+		require.Error(t, err, "should fail when IP is outside network range")
+		assert.Contains(t, err.Error(), "not within the account network range", "error should mention network range")
+	})
+
+	t.Run("update peer IP with invalid peer ID should fail", func(t *testing.T) {
+		newAddr := netip.MustParseAddr("100.64.0.101")
+		err := manager.UpdatePeerIP(context.Background(), accountID, userID, "invalid-peer-id", newAddr)
+		require.Error(t, err, "should fail with invalid peer ID")
+	})
+}

management/server/activity/codes.go

@@ -175,6 +175,9 @@ const (
 	AccountLazyConnectionEnabled  Activity = 85
 	AccountLazyConnectionDisabled Activity = 86
 
+	AccountNetworkRangeUpdated Activity = 87
+	PeerIPUpdated              Activity = 88
+
 	AccountDeleted Activity = 99999
 )
 
@@ -277,6 +280,10 @@ var activityMap = map[Activity]Code{
 
 	AccountLazyConnectionEnabled:  {"Account lazy connection enabled", "account.setting.lazy.connection.enable"},
 	AccountLazyConnectionDisabled: {"Account lazy connection disabled", "account.setting.lazy.connection.disable"},
+
+	AccountNetworkRangeUpdated: {"Account network range updated", "account.network.range.update"},
+
+	PeerIPUpdated: {"Peer IP updated", "peer.ip.update"},
 }
 
 // StringCode returns a string code of the activity

management/server/http/api/openapi.yml

@@ -133,6 +133,11 @@ components:
           description: Allows to define a custom dns domain for the account
           type: string
           example: my-organization.org
+        network_range:
+          description: Allows to define a custom network range for the account in CIDR format
+          type: string
+          format: cidr
+          example: 100.64.0.0/16
         extra:
           $ref: '#/components/schemas/AccountExtraSettings'
         lazy_connection_enabled:
@@ -342,6 +347,11 @@ components:
           description: (Cloud only) Indicates whether peer needs approval
           type: boolean
           example: true
+        ip:
+          description: Peer's IP address
+          type: string
+          format: ipv4
+          example: 100.64.0.15
       required:
         - name
         - ssh_enabled

management/server/http/api/types.gen.go

@@ -303,6 +303,9 @@ type AccountSettings struct {
 	// LazyConnectionEnabled Enables or disables experimental lazy connection
 	LazyConnectionEnabled *bool `json:"lazy_connection_enabled,omitempty"`
 
+	// NetworkRange Allows to define a custom network range for the account in CIDR format
+	NetworkRange *string `json:"network_range,omitempty"`
+
 	// PeerInactivityExpiration Period of time of inactivity after which peer session expires (seconds).
 	PeerInactivityExpiration int `json:"peer_inactivity_expiration"`
 
@@ -1196,11 +1199,14 @@ type PeerNetworkRangeCheckAction string
 // PeerRequest defines model for PeerRequest.
 type PeerRequest struct {
 	// ApprovalRequired (Cloud only) Indicates whether peer needs approval
-	ApprovalRequired            *bool  `json:"approval_required,omitempty"`
-	InactivityExpirationEnabled bool   `json:"inactivity_expiration_enabled"`
-	LoginExpirationEnabled      bool   `json:"login_expiration_enabled"`
-	Name                        string `json:"name"`
-	SshEnabled                  bool   `json:"ssh_enabled"`
+	ApprovalRequired            *bool `json:"approval_required,omitempty"`
+	InactivityExpirationEnabled bool  `json:"inactivity_expiration_enabled"`
+
+	// Ip Peer's IP address
+	Ip                     *string `json:"ip,omitempty"`
+	LoginExpirationEnabled bool    `json:"login_expiration_enabled"`
+	Name                   string  `json:"name"`
+	SshEnabled             bool    `json:"ssh_enabled"`
 }
 
 // PersonalAccessToken defines model for PersonalAccessToken.

management/server/http/handlers/accounts/accounts_handler.go

@@ -1,8 +1,10 @@
 package accounts
 
 import (
+	"context"
 	"encoding/json"
 	"net/http"
+	"net/netip"
 	"time"
 
 	"github.com/gorilla/mux"
@@ -16,6 +18,17 @@ import (
 	"github.com/netbirdio/netbird/management/server/types"
 )
 
+const (
+	// PeerBufferPercentage is the percentage of peers to add as buffer for network range calculations
+	PeerBufferPercentage = 0.5
+	// MinRequiredAddresses is the minimum number of addresses required in a network range
+	MinRequiredAddresses = 10
+	// MinNetworkBits is the minimum prefix length for IPv4 network ranges (e.g., /29 gives 8 addresses, /28 gives 16)
+	MinNetworkBitsIPv4 = 28
+	// MinNetworkBitsIPv6 is the minimum prefix length for IPv6 network ranges
+	MinNetworkBitsIPv6 = 120
+)
+
 // handler is a handler that handles the server.Account HTTP endpoints
 type handler struct {
 	accountManager  account.Manager
@@ -37,6 +50,86 @@ func newHandler(accountManager account.Manager, settingsManager settings.Manager
 	}
 }
 
+func validateIPAddress(addr netip.Addr) error {
+	if addr.IsLoopback() {
+		return status.Errorf(status.InvalidArgument, "loopback address range not allowed")
+	}
+
+	if addr.IsMulticast() {
+		return status.Errorf(status.InvalidArgument, "multicast address range not allowed")
+	}
+
+	if addr.IsLinkLocalUnicast() || addr.IsLinkLocalMulticast() {
+		return status.Errorf(status.InvalidArgument, "link-local address range not allowed")
+	}
+
+	return nil
+}
+
+func validateMinimumSize(prefix netip.Prefix) error {
+	addr := prefix.Addr()
+	if addr.Is4() && prefix.Bits() > MinNetworkBitsIPv4 {
+		return status.Errorf(status.InvalidArgument, "network range too small: minimum size is /%d for IPv4", MinNetworkBitsIPv4)
+	}
+	if addr.Is6() && prefix.Bits() > MinNetworkBitsIPv6 {
+		return status.Errorf(status.InvalidArgument, "network range too small: minimum size is /%d for IPv6", MinNetworkBitsIPv6)
+	}
+	return nil
+}
+
+func (h *handler) validateNetworkRange(ctx context.Context, accountID, userID string, networkRange netip.Prefix) error {
+	if !networkRange.IsValid() {
+		return nil
+	}
+
+	if err := validateIPAddress(networkRange.Addr()); err != nil {
+		return err
+	}
+
+	if err := validateMinimumSize(networkRange); err != nil {
+		return err
+	}
+
+	return h.validateCapacity(ctx, accountID, userID, networkRange)
+}
+
+func (h *handler) validateCapacity(ctx context.Context, accountID, userID string, prefix netip.Prefix) error {
+	peers, err := h.accountManager.GetPeers(ctx, accountID, userID, "", "")
+	if err != nil {
+		return status.Errorf(status.Internal, "get peer count: %v", err)
+	}
+
+	maxHosts := calculateMaxHosts(prefix)
+	requiredAddresses := calculateRequiredAddresses(len(peers))
+
+	if maxHosts < requiredAddresses {
+		return status.Errorf(status.InvalidArgument,
+			"network range too small: need at least %d addresses for %d peers + buffer, but range provides %d",
+			requiredAddresses, len(peers), maxHosts)
+	}
+
+	return nil
+}
+
+func calculateMaxHosts(prefix netip.Prefix) int64 {
+	availableAddresses := prefix.Addr().BitLen() - prefix.Bits()
+	maxHosts := int64(1) << availableAddresses
+
+	if prefix.Addr().Is4() {
+		maxHosts -= 2 // network and broadcast addresses
+	}
+
+	return maxHosts
+}
+
+func calculateRequiredAddresses(peerCount int) int64 {
+	requiredAddresses := int64(peerCount) + int64(float64(peerCount)*PeerBufferPercentage)
+	if requiredAddresses < MinRequiredAddresses {
+		requiredAddresses = MinRequiredAddresses
+	}
+	return requiredAddresses
+}
+
 // getAllAccounts is HTTP GET handler that returns a list of accounts. Effectively returns just a single account.
 func (h *handler) getAllAccounts(w http.ResponseWriter, r *http.Request) {
 	userAuth, err := nbcontext.GetUserAuthFromContext(r.Context())
@@ -131,6 +224,18 @@ func (h *handler) updateAccount(w http.ResponseWriter, r *http.Request) {
 	if req.Settings.LazyConnectionEnabled != nil {
 		settings.LazyConnectionEnabled = *req.Settings.LazyConnectionEnabled
 	}
+	if req.Settings.NetworkRange != nil && *req.Settings.NetworkRange != "" {
+		prefix, err := netip.ParsePrefix(*req.Settings.NetworkRange)
+		if err != nil {
+			util.WriteError(r.Context(), status.Errorf(status.InvalidArgument, "invalid CIDR format: %v", err), w)
+			return
+		}
+		if err := h.validateNetworkRange(r.Context(), accountID, userID, prefix); err != nil {
+			util.WriteError(r.Context(), err, w)
+			return
+		}
+		settings.NetworkRange = prefix
+	}
 
 	var onboarding *types.AccountOnboarding
 	if req.Onboarding != nil {
@@ -208,6 +313,11 @@ func toAccountResponse(accountID string, settings *types.Settings, meta *types.A
 		DnsDomain:                       &settings.DNSDomain,
 	}
 
+	if settings.NetworkRange.IsValid() {
+		networkRangeStr := settings.NetworkRange.String()
+		apiSettings.NetworkRange = &networkRangeStr
+	}
+
 	apiOnboarding := api.AccountOnboarding{
 		OnboardingFlowPending: onboarding.OnboardingFlowPending,
 		SignupFormPending:     onboarding.SignupFormPending,

management/server/http/handlers/peers/peers_handler.go

@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"net/http"
+	"net/netip"
 
 	"github.com/gorilla/mux"
 	log "github.com/sirupsen/logrus"
@@ -111,6 +112,19 @@ func (h *Handler) updatePeer(ctx context.Context, accountID, userID, peerID stri
 		}
 	}
 
+	if req.Ip != nil {
+		addr, err := netip.ParseAddr(*req.Ip)
+		if err != nil {
+			util.WriteError(ctx, status.Errorf(status.InvalidArgument, "invalid IP address %s: %v", *req.Ip, err), w)
+			return
+		}
+
+		if err = h.accountManager.UpdatePeerIP(ctx, accountID, userID, peerID, addr); err != nil {
+			util.WriteError(ctx, err, w)
+			return
+		}
+	}
+
 	peer, err := h.accountManager.UpdatePeer(ctx, accountID, userID, update)
 	if err != nil {
 		util.WriteError(ctx, err, w)

management/server/http/handlers/peers/peers_handler_test.go

@@ -9,6 +9,7 @@ import (
 	"net"
 	"net/http"
 	"net/http/httptest"
+	"net/netip"
 	"testing"
 	"time"
 
@@ -21,6 +22,7 @@ import (
 	"github.com/netbirdio/netbird/management/server/types"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 
 	"github.com/netbirdio/netbird/management/server/mock_server"
 )
@@ -112,6 +114,15 @@ func initTestMetaData(peers ...*nbpeer.Peer) *Handler {
 				p.Name = update.Name
 				return p, nil
 			},
+			UpdatePeerIPFunc: func(_ context.Context, accountID, userID, peerID string, newIP netip.Addr) error {
+				for _, peer := range peers {
+					if peer.ID == peerID {
+						peer.IP = net.IP(newIP.AsSlice())
+						return nil
+					}
+				}
+				return fmt.Errorf("peer not found")
+			},
 			GetPeerFunc: func(_ context.Context, accountID, peerID, userID string) (*nbpeer.Peer, error) {
 				var p *nbpeer.Peer
 				for _, peer := range peers {
@@ -450,3 +461,73 @@ func TestGetAccessiblePeers(t *testing.T) {
 		})
 	}
 }
+
+func TestPeersHandlerUpdatePeerIP(t *testing.T) {
+	testPeer := &nbpeer.Peer{
+		ID:                     testPeerID,
+		Key:                    "key",
+		IP:                     net.ParseIP("100.64.0.1"),
+		Status:                 &nbpeer.PeerStatus{Connected: false, LastSeen: time.Now()},
+		Name:                   "test-host@netbird.io",
+		LoginExpirationEnabled: false,
+		UserID:                 regularUser,
+		Meta: nbpeer.PeerSystemMeta{
+			Hostname: "test-host@netbird.io",
+			Core:     "22.04",
+		},
+	}
+
+	p := initTestMetaData(testPeer)
+
+	tt := []struct {
+		name           string
+		peerID         string
+		requestBody    string
+		callerUserID   string
+		expectedStatus int
+		expectedIP     string
+	}{
+		{
+			name:           "update peer IP successfully",
+			peerID:         testPeerID,
+			requestBody:    `{"ip": "100.64.0.100"}`,
+			callerUserID:   adminUser,
+			expectedStatus: http.StatusOK,
+			expectedIP:     "100.64.0.100",
+		},
+		{
+			name:           "update peer IP with invalid IP",
+			peerID:         testPeerID,
+			requestBody:    `{"ip": "invalid-ip"}`,
+			callerUserID:   adminUser,
+			expectedStatus: http.StatusUnprocessableEntity,
+		},
+	}
+
+	for _, tc := range tt {
+		t.Run(tc.name, func(t *testing.T) {
+			req := httptest.NewRequest(http.MethodPut, fmt.Sprintf("/peers/%s", tc.peerID), bytes.NewBuffer([]byte(tc.requestBody)))
+			req.Header.Set("Content-Type", "application/json")
+			req = nbcontext.SetUserAuthInRequest(req, nbcontext.UserAuth{
+				UserId:    tc.callerUserID,
+				Domain:    "hotmail.com",
+				AccountId: "test_id",
+			})
+
+			rr := httptest.NewRecorder()
+			router := mux.NewRouter()
+			router.HandleFunc("/peers/{peerId}", p.HandlePeer).Methods("PUT")
+
+			router.ServeHTTP(rr, req)
+
+			assert.Equal(t, tc.expectedStatus, rr.Code)
+
+			if tc.expectedStatus == http.StatusOK && tc.expectedIP != "" {
+				var updatedPeer api.Peer
+				err := json.Unmarshal(rr.Body.Bytes(), &updatedPeer)
+				require.NoError(t, err)
+				assert.Equal(t, tc.expectedIP, updatedPeer.Ip)
+			}
+		})
+	}
+}

management/server/mock_server/account_mock.go

@@ -60,6 +60,7 @@ type MockAccountManager struct {
 	GetUsersFromAccountFunc               func(ctx context.Context, accountID, userID string) (map[string]*types.UserInfo, error)
 	UpdatePeerMetaFunc                    func(ctx context.Context, peerID string, meta nbpeer.PeerSystemMeta) error
 	UpdatePeerFunc                        func(ctx context.Context, accountID, userID string, peer *nbpeer.Peer) (*nbpeer.Peer, error)
+	UpdatePeerIPFunc                      func(ctx context.Context, accountID, userID, peerID string, newIP netip.Addr) error
 	CreateRouteFunc                       func(ctx context.Context, accountID string, prefix netip.Prefix, networkType route.NetworkType, domains domain.List, peer string, peerGroups []string, description string, netID route.NetID, masquerade bool, metric int, groups, accessControlGroupIDs []string, enabled bool, userID string, keepRoute bool) (*route.Route, error)
 	GetRouteFunc                          func(ctx context.Context, accountID string, routeID route.ID, userID string) (*route.Route, error)
 	SaveRouteFunc                         func(ctx context.Context, accountID string, userID string, route *route.Route) error
@@ -483,6 +484,13 @@ func (am *MockAccountManager) UpdatePeer(ctx context.Context, accountID, userID
 	return nil, status.Errorf(codes.Unimplemented, "method UpdatePeer is not implemented")
 }
 
+func (am *MockAccountManager) UpdatePeerIP(ctx context.Context, accountID, userID, peerID string, newIP netip.Addr) error {
+	if am.UpdatePeerIPFunc != nil {
+		return am.UpdatePeerIPFunc(ctx, accountID, userID, peerID, newIP)
+	}
+	return status.Errorf(codes.Unimplemented, "method UpdatePeerIP is not implemented")
+}
+
 // CreateRoute mock implementation of CreateRoute from server.AccountManager interface
 func (am *MockAccountManager) CreateRoute(ctx context.Context, accountID string, prefix netip.Prefix, networkType route.NetworkType, domains domain.List, peerID string, peerGroupIDs []string, description string, netID route.NetID, masquerade bool, metric int, groups, accessControlGroupID []string, enabled bool, userID string, keepRoute bool) (*route.Route, error) {
 	if am.CreateRouteFunc != nil {

management/server/types/network.go

@@ -163,7 +163,10 @@ func (n *Network) Copy() *Network {
 // E.g. if ipNet=100.30.0.0/16 and takenIps=[100.30.0.1, 100.30.0.4] then the result would be 100.30.0.2 or 100.30.0.3
 func AllocatePeerIP(ipNet net.IPNet, takenIps []net.IP) (net.IP, error) {
 	baseIP := ipToUint32(ipNet.IP.Mask(ipNet.Mask))
-	totalIPs := uint32(1 << SubnetSize)
+
+	ones, bits := ipNet.Mask.Size()
+	hostBits := bits - ones
+	totalIPs := uint32(1 << hostBits)
 
 	taken := make(map[uint32]struct{}, len(takenIps)+1)
 	taken[baseIP] = struct{}{}            // reserve network IP

management/server/types/network_test.go

@@ -5,6 +5,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 func TestNewNetwork(t *testing.T) {
@@ -38,6 +39,107 @@ func TestAllocatePeerIP(t *testing.T) {
 	}
 }
 
+func TestAllocatePeerIPSmallSubnet(t *testing.T) {
+	// Test /27 network (10.0.0.0/27) - should only have 30 usable IPs (10.0.0.1 to 10.0.0.30)
+	ipNet := net.IPNet{IP: net.ParseIP("10.0.0.0"), Mask: net.IPMask{255, 255, 255, 224}}
+	var ips []net.IP
+
+	// Allocate all available IPs in the /27 network
+	for i := 0; i < 30; i++ {
+		ip, err := AllocatePeerIP(ipNet, ips)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		// Verify IP is within the correct range
+		if !ipNet.Contains(ip) {
+			t.Errorf("allocated IP %s is not within network %s", ip.String(), ipNet.String())
+		}
+
+		ips = append(ips, ip)
+	}
+
+	assert.Len(t, ips, 30)
+
+	// Verify all IPs are unique
+	uniq := make(map[string]struct{})
+	for _, ip := range ips {
+		if _, ok := uniq[ip.String()]; !ok {
+			uniq[ip.String()] = struct{}{}
+		} else {
+			t.Errorf("found duplicate IP %s", ip.String())
+		}
+	}
+
+	// Try to allocate one more IP - should fail as network is full
+	_, err := AllocatePeerIP(ipNet, ips)
+	if err == nil {
+		t.Error("expected error when network is full, but got none")
+	}
+}
+
+func TestAllocatePeerIPVariousCIDRs(t *testing.T) {
+	testCases := []struct {
+		name           string
+		cidr           string
+		expectedUsable int
+	}{
+		{"/30 network", "192.168.1.0/30", 2},   // 4 total - 2 reserved = 2 usable
+		{"/29 network", "192.168.1.0/29", 6},   // 8 total - 2 reserved = 6 usable
+		{"/28 network", "192.168.1.0/28", 14},  // 16 total - 2 reserved = 14 usable
+		{"/27 network", "192.168.1.0/27", 30},  // 32 total - 2 reserved = 30 usable
+		{"/26 network", "192.168.1.0/26", 62},  // 64 total - 2 reserved = 62 usable
+		{"/25 network", "192.168.1.0/25", 126}, // 128 total - 2 reserved = 126 usable
+		{"/16 network", "10.0.0.0/16", 65534},  // 65536 total - 2 reserved = 65534 usable
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			_, ipNet, err := net.ParseCIDR(tc.cidr)
+			require.NoError(t, err)
+
+			var ips []net.IP
+
+			// For larger networks, test only a subset to avoid long test runs
+			testCount := tc.expectedUsable
+			if testCount > 1000 {
+				testCount = 1000
+			}
+
+			// Allocate IPs and verify they're within the correct range
+			for i := 0; i < testCount; i++ {
+				ip, err := AllocatePeerIP(*ipNet, ips)
+				require.NoError(t, err, "failed to allocate IP %d", i)
+
+				// Verify IP is within the correct range
+				assert.True(t, ipNet.Contains(ip), "allocated IP %s is not within network %s", ip.String(), ipNet.String())
+
+				// Verify IP is not network or broadcast address
+				networkIP := ipNet.IP.Mask(ipNet.Mask)
+				ones, bits := ipNet.Mask.Size()
+				hostBits := bits - ones
+				broadcastInt := uint32(ipToUint32(networkIP)) + (1 << hostBits) - 1
+				broadcastIP := uint32ToIP(broadcastInt)
+
+				assert.False(t, ip.Equal(networkIP), "allocated network address %s", ip.String())
+				assert.False(t, ip.Equal(broadcastIP), "allocated broadcast address %s", ip.String())
+
+				ips = append(ips, ip)
+			}
+
+			assert.Len(t, ips, testCount)
+
+			// Verify all IPs are unique
+			uniq := make(map[string]struct{})
+			for _, ip := range ips {
+				ipStr := ip.String()
+				assert.NotContains(t, uniq, ipStr, "found duplicate IP %s", ipStr)
+				uniq[ipStr] = struct{}{}
+			}
+		})
+	}
+}
+
 func TestGenerateIPs(t *testing.T) {
 	ipNet := net.IPNet{IP: net.ParseIP("100.64.0.0"), Mask: net.IPMask{255, 255, 255, 0}}
 	ips, ipsLen := generateIPs(&ipNet, map[string]struct{}{"100.64.0.0": {}})

management/server/types/settings.go

@@ -1,6 +1,7 @@
 package types
 
 import (
+	"net/netip"
 	"time"
 )
 
@@ -42,6 +43,9 @@ type Settings struct {
 	// DNSDomain is the custom domain for that account
 	DNSDomain string
 
+	// NetworkRange is the custom network range for that account
+	NetworkRange netip.Prefix `gorm:"serializer:json"`
+
 	// Extra is a dictionary of Account settings
 	Extra *ExtraSettings `gorm:"embedded;embeddedPrefix:extra_"`
 
@@ -66,6 +70,7 @@ func (s *Settings) Copy() *Settings {
 		RoutingPeerDNSResolutionEnabled: s.RoutingPeerDNSResolutionEnabled,
 		LazyConnectionEnabled:           s.LazyConnectionEnabled,
 		DNSDomain:                       s.DNSDomain,
+		NetworkRange:                    s.NetworkRange,
 	}
 	if s.Extra != nil {
 		settings.Extra = s.Extra.Copy()

util/common.go

@@ -23,7 +23,6 @@ func FileExists(path string) bool {
 	return err == nil
 }
 
-
 /// Bool helpers
 
 // True returns a *bool whose underlying value is true.

util/duration.go

@@ -6,7 +6,7 @@ import (
 	"time"
 )
 
-//Duration is used strictly for JSON requests/responses due to duration marshalling issues
+// Duration is used strictly for JSON requests/responses due to duration marshalling issues
 type Duration struct {
 	time.Duration
 }