/
router.go
264 lines (227 loc) · 5.75 KB
/
router.go
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package chain
import (
"bytes"
"context"
"fmt"
"net"
"time"
"github.com/go-gost/core/hosts"
"github.com/go-gost/core/logger"
"github.com/go-gost/core/recorder"
"github.com/go-gost/core/resolver"
)
type SockOpts struct {
Mark int
}
type RouterOptions struct {
Retries int
Timeout time.Duration
IfceName string
SockOpts *SockOpts
Chain Chainer
Resolver resolver.Resolver
HostMapper hosts.HostMapper
Recorders []recorder.RecorderObject
Logger logger.Logger
}
type RouterOption func(*RouterOptions)
func InterfaceRouterOption(ifceName string) RouterOption {
return func(o *RouterOptions) {
o.IfceName = ifceName
}
}
func SockOptsRouterOption(so *SockOpts) RouterOption {
return func(o *RouterOptions) {
o.SockOpts = so
}
}
func TimeoutRouterOption(timeout time.Duration) RouterOption {
return func(o *RouterOptions) {
o.Timeout = timeout
}
}
func RetriesRouterOption(retries int) RouterOption {
return func(o *RouterOptions) {
o.Retries = retries
}
}
func ChainRouterOption(chain Chainer) RouterOption {
return func(o *RouterOptions) {
o.Chain = chain
}
}
func ResolverRouterOption(resolver resolver.Resolver) RouterOption {
return func(o *RouterOptions) {
o.Resolver = resolver
}
}
func HostMapperRouterOption(m hosts.HostMapper) RouterOption {
return func(o *RouterOptions) {
o.HostMapper = m
}
}
func RecordersRouterOption(recorders ...recorder.RecorderObject) RouterOption {
return func(o *RouterOptions) {
o.Recorders = recorders
}
}
func LoggerRouterOption(logger logger.Logger) RouterOption {
return func(o *RouterOptions) {
o.Logger = logger
}
}
// Router:是Route的实例化,实现了Bind/Dial/Nodes方法
type Router struct {
options RouterOptions
}
// 初始化router
func NewRouter(opts ...RouterOption) *Router {
r := &Router{}
for _, opt := range opts {
if opt != nil {
opt(&r.options)
}
}
if r.options.Logger == nil {
r.options.Logger = logger.Default().WithFields(map[string]any{"kind": "router"})
}
return r
}
func (r *Router) Options() *RouterOptions {
if r == nil {
return nil
}
return &r.options
}
func (r *Router) Dial(ctx context.Context, network, address string) (conn net.Conn, err error) {
host := address
if h, _, _ := net.SplitHostPort(address); h != "" {
host = h
}
r.record(ctx, recorder.RecorderServiceRouterDialAddress, []byte(host))
conn, err = r.dial(ctx, network, address)
if err != nil {
r.record(ctx, recorder.RecorderServiceRouterDialAddressError, []byte(host))
return
}
if network == "udp" || network == "udp4" || network == "udp6" {
if _, ok := conn.(net.PacketConn); !ok {
return &packetConn{conn}, nil
}
}
return
}
func (r *Router) record(ctx context.Context, name string, data []byte) error {
if len(data) == 0 {
return nil
}
for _, rec := range r.options.Recorders {
if rec.Record == name {
err := rec.Recorder.Record(ctx, data)
if err != nil {
r.options.Logger.Errorf("record %s: %v", name, err)
}
return err
}
}
return nil
}
func (r *Router) dial(ctx context.Context, network, address string) (conn net.Conn, err error) {
count := r.options.Retries + 1
if count <= 0 {
count = 1
}
r.options.Logger.Debugf("dial %s/%s", address, network)
for i := 0; i < count; i++ {
var ipAddr string
ipAddr, err = Resolve(ctx, "ip", address, r.options.Resolver, r.options.HostMapper, r.options.Logger)
if err != nil {
r.options.Logger.Error(err)
break
}
var route Route
if r.options.Chain != nil {
//构建最终的route结构,这个route里面包含了nodes []*chain.Node结构,用于最终连接
route = r.options.Chain.Route(ctx, network, ipAddr, WithHostRouteOption(address))
}
if r.options.Logger.IsLevelEnabled(logger.DebugLevel) {
buf := bytes.Buffer{}
for _, node := range routePath(route) {
fmt.Fprintf(&buf, "%s@%s > ", node.Name, node.Addr)
}
fmt.Fprintf(&buf, "%s", ipAddr)
r.options.Logger.Debugf("route(retry=%d) %s", i, buf.String())
}
if route == nil {
route = DefaultRoute
}
conn, err = route.Dial(ctx, network, ipAddr,
InterfaceDialOption(r.options.IfceName),
SockOptsDialOption(r.options.SockOpts),
LoggerDialOption(r.options.Logger),
TimeoutDialOption(r.options.Timeout),
)
if err == nil {
break
}
r.options.Logger.Errorf("route(retry=%d) %s", i, err)
}
return
}
func (r *Router) Bind(ctx context.Context, network, address string, opts ...BindOption) (ln net.Listener, err error) {
count := r.options.Retries + 1
if count <= 0 {
count = 1
}
r.options.Logger.Debugf("bind on %s/%s", address, network)
for i := 0; i < count; i++ {
var route Route
if r.options.Chain != nil {
route = r.options.Chain.Route(ctx, network, address)
if route == nil || len(route.Nodes()) == 0 {
err = ErrEmptyRoute
return
}
}
if r.options.Logger.IsLevelEnabled(logger.DebugLevel) {
buf := bytes.Buffer{}
for _, node := range routePath(route) {
fmt.Fprintf(&buf, "%s@%s > ", node.Name, node.Addr)
}
fmt.Fprintf(&buf, "%s", address)
r.options.Logger.Debugf("route(retry=%d) %s", i, buf.String())
}
if route == nil {
route = DefaultRoute
}
ln, err = route.Bind(ctx, network, address, opts...)
if err == nil {
break
}
r.options.Logger.Errorf("route(retry=%d) %s", i, err)
}
return
}
func routePath(route Route) (path []*Node) {
if route == nil {
return
}
for _, node := range route.Nodes() {
if tr := node.Options().Transport; tr != nil {
path = append(path, routePath(tr.Options().Route)...)
}
path = append(path, node)
}
return
}
type packetConn struct {
net.Conn
}
func (c *packetConn) ReadFrom(b []byte) (n int, addr net.Addr, err error) {
n, err = c.Read(b)
addr = c.Conn.RemoteAddr()
return
}
func (c *packetConn) WriteTo(b []byte, addr net.Addr) (n int, err error) {
return c.Write(b)
}