x/handler/socks/v5/handler.go
2023-11-18 18:28:09 +08:00

139 lines
3.0 KiB
Go

package v5
import (
"context"
"errors"
"net"
"time"
"github.com/go-gost/core/chain"
"github.com/go-gost/core/handler"
md "github.com/go-gost/core/metadata"
"github.com/go-gost/gosocks5"
ctxvalue "github.com/go-gost/x/internal/ctx"
"github.com/go-gost/x/internal/util/socks"
"github.com/go-gost/x/registry"
)
var (
ErrUnknownCmd = errors.New("socks5: unknown command")
)
func init() {
registry.HandlerRegistry().Register("socks5", NewHandler)
registry.HandlerRegistry().Register("socks", NewHandler)
}
type socks5Handler struct {
selector gosocks5.Selector
router *chain.Router
md metadata
options handler.Options
}
func NewHandler(opts ...handler.Option) handler.Handler {
options := handler.Options{}
for _, opt := range opts {
opt(&options)
}
return &socks5Handler{
options: options,
}
}
func (h *socks5Handler) Init(md md.Metadata) (err error) {
if err = h.parseMetadata(md); err != nil {
return
}
h.router = h.options.Router
if h.router == nil {
h.router = chain.NewRouter(chain.LoggerRouterOption(h.options.Logger))
}
h.selector = &serverSelector{
Authenticator: h.options.Auther,
TLSConfig: h.options.TLSConfig,
logger: h.options.Logger,
noTLS: h.md.noTLS,
}
return
}
func (h *socks5Handler) Handle(ctx context.Context, conn net.Conn, opts ...handler.HandleOption) error {
defer conn.Close()
start := time.Now()
log := h.options.Logger.WithFields(map[string]any{
"remote": conn.RemoteAddr().String(),
"local": conn.LocalAddr().String(),
})
log.Infof("%s <> %s", conn.RemoteAddr(), conn.LocalAddr())
defer func() {
log.WithFields(map[string]any{
"duration": time.Since(start),
}).Infof("%s >< %s", conn.RemoteAddr(), conn.LocalAddr())
}()
if !h.checkRateLimit(conn.RemoteAddr()) {
return nil
}
if h.md.readTimeout > 0 {
conn.SetReadDeadline(time.Now().Add(h.md.readTimeout))
}
sc := gosocks5.ServerConn(conn, h.selector)
req, err := gosocks5.ReadRequest(sc)
if err != nil {
log.Error(err)
return err
}
log.Trace(req)
if clientID := sc.ID(); clientID != "" {
ctx = ctxvalue.ContextWithClientID(ctx, ctxvalue.ClientID(clientID))
}
conn = sc
conn.SetReadDeadline(time.Time{})
address := req.Addr.String()
switch req.Cmd {
case gosocks5.CmdConnect:
return h.handleConnect(ctx, conn, "tcp", address, log)
case gosocks5.CmdBind:
return h.handleBind(ctx, conn, "tcp", address, log)
case socks.CmdMuxBind:
return h.handleMuxBind(ctx, conn, "tcp", address, log)
case gosocks5.CmdUdp:
return h.handleUDP(ctx, conn, log)
case socks.CmdUDPTun:
return h.handleUDPTun(ctx, conn, "udp", address, log)
default:
err = ErrUnknownCmd
log.Error(err)
resp := gosocks5.NewReply(gosocks5.CmdUnsupported, nil)
log.Trace(resp)
resp.Write(conn)
return err
}
}
func (h *socks5Handler) checkRateLimit(addr net.Addr) bool {
if h.options.RateLimiter == nil {
return true
}
host, _, _ := net.SplitHostPort(addr.String())
if limiter := h.options.RateLimiter.Limiter(host); limiter != nil {
return limiter.Allow(1)
}
return true
}