Files
Reticulum-Go/pkg/transport/transport.go
2024-12-30 01:56:25 -06:00

459 lines
10 KiB
Go

package transport
import (
"encoding/binary"
"errors"
"net"
"sync"
"time"
"github.com/Sudo-Ivan/reticulum-go/pkg/common"
)
var (
transportInstance *Transport
transportMutex sync.Mutex
)
const (
PathfinderM = 128 // Maximum number of hops
PathRequestTTL = 300 // Time to live for path requests in seconds
AnnounceTimeout = 15 // Timeout for announce responses in seconds
// Link constants
EstablishmentTimeoutPerHop = 6 // Timeout for link establishment in seconds per hop
KeepaliveTimeoutFactor = 4 // RTT timeout factor for link timeout calculation
StaleGrace = 2 // Grace period in seconds for link timeout
Keepalive = 360 // Interval for sending keep-alive packets in seconds
StaleTime = 720 // Time after which link is considered stale
// Direction constants
OUT = 0x02
IN = 0x01
// Destination type constants
SINGLE = 0x00
GROUP = 0x01
PLAIN = 0x02
)
type PathInfo struct {
NextHop []byte
Interface string
Hops uint8
LastUpdated time.Time
}
type Transport struct {
config *common.ReticulumConfig
interfaces map[string]common.NetworkInterface
paths map[string]*common.Path
announceHandlers []AnnounceHandler
mutex sync.RWMutex
handlerLock sync.RWMutex
pathLock sync.RWMutex
}
func NewTransport(config *common.ReticulumConfig) (*Transport, error) {
t := &Transport{
config: config,
interfaces: make(map[string]common.NetworkInterface),
paths: make(map[string]*common.Path),
}
transportMutex.Lock()
transportInstance = t
transportMutex.Unlock()
return t, nil
}
// Add GetTransportInstance function
func GetTransportInstance() *Transport {
transportMutex.Lock()
defer transportMutex.Unlock()
return transportInstance
}
// Update the interface methods
func (t *Transport) RegisterInterface(name string, iface common.NetworkInterface) error {
t.mutex.Lock()
defer t.mutex.Unlock()
if _, exists := t.interfaces[name]; exists {
return errors.New("interface already registered")
}
t.interfaces[name] = iface
return nil
}
func (t *Transport) GetInterface(name string) (common.NetworkInterface, error) {
t.mutex.RLock()
defer t.mutex.RUnlock()
iface, exists := t.interfaces[name]
if !exists {
return nil, errors.New("interface not found")
}
return iface, nil
}
// Update the Close method
func (t *Transport) Close() error {
t.mutex.Lock()
defer t.mutex.Unlock()
for _, iface := range t.interfaces {
iface.Detach()
}
return nil
}
type Link struct {
destination []byte
establishedAt time.Time
lastInbound time.Time
lastOutbound time.Time
lastData time.Time
rtt time.Duration
establishedCb func()
closedCb func()
packetCb func([]byte)
resourceCb func(interface{}) bool
resourceStrategy int
}
type Destination struct {
Identity interface{}
Direction int
Type int
AppName string
Aspects []string
}
func NewLink(dest []byte, establishedCallback func(), closedCallback func()) *Link {
return &Link{
destination: dest,
establishedAt: time.Now(),
lastInbound: time.Now(),
lastOutbound: time.Now(),
lastData: time.Now(),
establishedCb: establishedCallback,
closedCb: closedCallback,
}
}
// Link methods
func (l *Link) GetAge() time.Duration {
return time.Since(l.establishedAt)
}
func (l *Link) NoInboundFor() time.Duration {
return time.Since(l.lastInbound)
}
func (l *Link) NoOutboundFor() time.Duration {
return time.Since(l.lastOutbound)
}
func (l *Link) NoDataFor() time.Duration {
return time.Since(l.lastData)
}
func (l *Link) InactiveFor() time.Duration {
inbound := l.NoInboundFor()
outbound := l.NoOutboundFor()
if inbound < outbound {
return inbound
}
return outbound
}
func (l *Link) SetPacketCallback(cb func([]byte)) {
l.packetCb = cb
}
func (l *Link) SetResourceCallback(cb func(interface{}) bool) {
l.resourceCb = cb
}
func (l *Link) Teardown() {
if l.closedCb != nil {
l.closedCb()
}
}
func (l *Link) Send(data []byte) error {
l.lastOutbound = time.Now()
l.lastData = time.Now()
packet := &LinkPacket{
Destination: l.destination,
Data: data,
Timestamp: time.Now(),
}
if l.rtt == 0 {
l.rtt = l.InactiveFor()
}
return packet.send()
}
type AnnounceHandler interface {
ReceivedAnnounce(destinationHash []byte, identity interface{}, appData []byte)
}
func (t *Transport) RegisterAnnounceHandler(handler AnnounceHandler) {
t.handlerLock.Lock()
defer t.handlerLock.Unlock()
t.announceHandlers = append(t.announceHandlers, handler)
}
func (t *Transport) DeregisterAnnounceHandler(handler AnnounceHandler) {
t.handlerLock.Lock()
defer t.handlerLock.Unlock()
for i, h := range t.announceHandlers {
if h == handler {
t.announceHandlers = append(t.announceHandlers[:i], t.announceHandlers[i+1:]...)
return
}
}
}
func (t *Transport) HasPath(destinationHash []byte) bool {
t.pathLock.RLock()
defer t.pathLock.RUnlock()
path, exists := t.paths[string(destinationHash)]
if !exists {
return false
}
// Check if path is still valid (not expired)
if time.Since(path.LastUpdated) > time.Duration(PathRequestTTL)*time.Second {
delete(t.paths, string(destinationHash))
return false
}
return true
}
func (t *Transport) HopsTo(destinationHash []byte) uint8 {
t.pathLock.RLock()
defer t.pathLock.RUnlock()
path, exists := t.paths[string(destinationHash)]
if !exists {
return PathfinderM
}
return path.Hops
}
func (t *Transport) NextHop(destinationHash []byte) []byte {
t.pathLock.RLock()
defer t.pathLock.RUnlock()
path, exists := t.paths[string(destinationHash)]
if !exists {
return nil
}
return path.NextHop
}
func (t *Transport) NextHopInterface(destinationHash []byte) string {
t.pathLock.RLock()
defer t.pathLock.RUnlock()
path, exists := t.paths[string(destinationHash)]
if !exists {
return ""
}
return path.Interface.GetName()
}
func (t *Transport) RequestPath(destinationHash []byte, onInterface string, tag []byte, recursive bool) error {
packet := &PathRequest{
DestinationHash: destinationHash,
Tag: tag,
TTL: PathRequestTTL,
Recursive: recursive,
}
if onInterface != "" {
return t.sendPathRequest(packet, onInterface)
}
return t.broadcastPathRequest(packet)
}
func (t *Transport) UpdatePath(destinationHash []byte, nextHop []byte, interfaceName string, hops uint8) {
t.pathLock.Lock()
defer t.pathLock.Unlock()
iface, err := t.GetInterface(interfaceName)
if err != nil {
return
}
t.paths[string(destinationHash)] = &common.Path{
Interface: iface,
NextHop: nextHop,
Hops: hops,
LastUpdated: time.Now(),
}
}
func (t *Transport) HandleAnnounce(destinationHash []byte, identity []byte, appData []byte) {
t.handlerLock.RLock()
defer t.handlerLock.RUnlock()
for _, handler := range t.announceHandlers {
handler.ReceivedAnnounce(destinationHash, identity, appData)
}
}
func (t *Transport) NewDestination(identity interface{}, direction int, destType int, appName string, aspects ...string) *Destination {
return &Destination{
Identity: identity,
Direction: direction,
Type: destType,
AppName: appName,
Aspects: aspects,
}
}
func (t *Transport) NewLink(dest []byte, establishedCallback func(), closedCallback func()) *Link {
return NewLink(dest, establishedCallback, closedCallback)
}
type PathRequest struct {
DestinationHash []byte
Tag []byte
TTL int
Recursive bool
}
type LinkPacket struct {
Destination []byte
Data []byte
Timestamp time.Time
}
func (p *LinkPacket) send() error {
// Get transport instance
t := GetTransportInstance()
// Create packet header
header := make([]byte, 0, 64)
header = append(header, 0x02) // Link packet type
header = append(header, p.Destination...)
// Add timestamp
ts := make([]byte, 8)
binary.BigEndian.PutUint64(ts, uint64(p.Timestamp.Unix()))
header = append(header, ts...)
// Combine header and data
packet := append(header, p.Data...)
// Get next hop info
nextHop := t.NextHop(p.Destination)
if nextHop == nil {
return errors.New("no path to destination")
}
// Get interface for next hop
ifaceName := t.NextHopInterface(p.Destination)
iface, ok := t.interfaces[ifaceName]
if !ok {
return errors.New("interface not found")
}
// Send packet using interface's Send method
return iface.Send(packet, "")
}
func (t *Transport) sendPathRequest(req *PathRequest, interfaceName string) error {
// Create path request packet
packet := &PathRequestPacket{
Type: 0x01,
DestinationHash: req.DestinationHash,
Tag: req.Tag,
TTL: byte(req.TTL),
Recursive: req.Recursive,
}
// Serialize packet
buf := make([]byte, 0, 128)
buf = append(buf, packet.Type)
buf = append(buf, packet.DestinationHash...)
buf = append(buf, packet.Tag...)
buf = append(buf, packet.TTL)
if packet.Recursive {
buf = append(buf, 0x01)
} else {
buf = append(buf, 0x00)
}
// Get interface
iface, ok := t.interfaces[interfaceName]
if !ok {
return errors.New("interface not found")
}
return iface.Send(buf, "")
}
func (t *Transport) broadcastPathRequest(req *PathRequest) error {
var lastErr error
for _, iface := range t.interfaces {
if !iface.IsEnabled() {
continue
}
if err := t.sendPathRequest(req, iface.GetName()); err != nil {
lastErr = err
}
}
return lastErr
}
type PathRequestPacket struct {
Type byte // 0x01 for path request
DestinationHash []byte // 32 bytes
Tag []byte // Variable length
TTL byte
Recursive bool
}
type NetworkInterface struct {
Name string
Addr *net.UDPAddr
Conn *net.UDPConn
MTU int
Enabled bool
}
func SendAnnounce(packet []byte) error {
t := GetTransportInstance()
if t == nil {
return errors.New("transport not initialized")
}
// Send announce packet to all interfaces
var lastErr error
for _, iface := range t.interfaces {
if err := iface.Send(packet, ""); err != nil {
lastErr = err
}
}
return lastErr
}