init

handler.go

@@ -0,0 +1,270 @@
+package gost
+
+import (
+	"bufio"
+	"crypto/tls"
+	"net"
+	"net/url"
+	"time"
+
+	"github.com/go-gost/gosocks4"
+	"github.com/go-gost/gosocks5"
+	"github.com/go-log/log"
+)
+
+// Handler is a proxy server handler
+type Handler interface {
+	Init(options ...HandlerOption)
+	Handle(net.Conn)
+}
+
+// HandlerOptions describes the options for Handler.
+type HandlerOptions struct {
+	Addr          string
+	Chain         *Chain
+	Users         []*url.Userinfo
+	Authenticator Authenticator
+	TLSConfig     *tls.Config
+	Whitelist     *Permissions
+	Blacklist     *Permissions
+	Strategy      Strategy
+	MaxFails      int
+	FailTimeout   time.Duration
+	Bypass        *Bypass
+	Retries       int
+	Timeout       time.Duration
+	Resolver      Resolver
+	Hosts         *Hosts
+	ProbeResist   string
+	KnockingHost  string
+	Node          Node
+	Host          string
+	IPs           []string
+	TCPMode       bool
+	IPRoutes      []IPRoute
+}
+
+// HandlerOption allows a common way to set handler options.
+type HandlerOption func(opts *HandlerOptions)
+
+// AddrHandlerOption sets the Addr option of HandlerOptions.
+func AddrHandlerOption(addr string) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.Addr = addr
+	}
+}
+
+// ChainHandlerOption sets the Chain option of HandlerOptions.
+func ChainHandlerOption(chain *Chain) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.Chain = chain
+	}
+}
+
+// UsersHandlerOption sets the Users option of HandlerOptions.
+func UsersHandlerOption(users ...*url.Userinfo) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.Users = users
+
+		kvs := make(map[string]string)
+		for _, u := range users {
+			if u != nil {
+				kvs[u.Username()], _ = u.Password()
+			}
+		}
+		if len(kvs) > 0 {
+			opts.Authenticator = NewLocalAuthenticator(kvs)
+		}
+	}
+}
+
+// AuthenticatorHandlerOption sets the Authenticator option of HandlerOptions.
+func AuthenticatorHandlerOption(au Authenticator) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.Authenticator = au
+	}
+}
+
+// TLSConfigHandlerOption sets the TLSConfig option of HandlerOptions.
+func TLSConfigHandlerOption(config *tls.Config) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.TLSConfig = config
+	}
+}
+
+// WhitelistHandlerOption sets the Whitelist option of HandlerOptions.
+func WhitelistHandlerOption(whitelist *Permissions) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.Whitelist = whitelist
+	}
+}
+
+// BlacklistHandlerOption sets the Blacklist option of HandlerOptions.
+func BlacklistHandlerOption(blacklist *Permissions) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.Blacklist = blacklist
+	}
+}
+
+// BypassHandlerOption sets the bypass option of HandlerOptions.
+func BypassHandlerOption(bypass *Bypass) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.Bypass = bypass
+	}
+}
+
+// StrategyHandlerOption sets the strategy option of HandlerOptions.
+func StrategyHandlerOption(strategy Strategy) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.Strategy = strategy
+	}
+}
+
+// MaxFailsHandlerOption sets the max_fails option of HandlerOptions.
+func MaxFailsHandlerOption(n int) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.MaxFails = n
+	}
+}
+
+// FailTimeoutHandlerOption sets the fail_timeout option of HandlerOptions.
+func FailTimeoutHandlerOption(d time.Duration) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.FailTimeout = d
+	}
+}
+
+// RetryHandlerOption sets the retry option of HandlerOptions.
+func RetryHandlerOption(retries int) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.Retries = retries
+	}
+}
+
+// TimeoutHandlerOption sets the timeout option of HandlerOptions.
+func TimeoutHandlerOption(timeout time.Duration) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.Timeout = timeout
+	}
+}
+
+// ResolverHandlerOption sets the resolver option of HandlerOptions.
+func ResolverHandlerOption(resolver Resolver) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.Resolver = resolver
+	}
+}
+
+// HostsHandlerOption sets the Hosts option of HandlerOptions.
+func HostsHandlerOption(hosts *Hosts) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.Hosts = hosts
+	}
+}
+
+// ProbeResistHandlerOption adds the probe resistance for HTTP proxy.
+func ProbeResistHandlerOption(pr string) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.ProbeResist = pr
+	}
+}
+
+// KnockingHandlerOption adds the knocking host for probe resistance.
+func KnockingHandlerOption(host string) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.KnockingHost = host
+	}
+}
+
+// NodeHandlerOption set the server node for server handler.
+func NodeHandlerOption(node Node) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.Node = node
+	}
+}
+
+// HostHandlerOption sets the target host for SNI proxy.
+func HostHandlerOption(host string) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.Host = host
+	}
+}
+
+// IPsHandlerOption sets the ip list for port forward.
+func IPsHandlerOption(ips []string) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.IPs = ips
+	}
+}
+
+// TCPModeHandlerOption sets the tcp mode for tun/tap device.
+func TCPModeHandlerOption(b bool) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.TCPMode = b
+	}
+}
+
+// IPRoutesHandlerOption sets the IP routes for tun tunnel.
+func IPRoutesHandlerOption(routes ...IPRoute) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.IPRoutes = routes
+	}
+}
+
+type autoHandler struct {
+	options *HandlerOptions
+}
+
+// AutoHandler creates a server Handler for auto proxy server.
+func AutoHandler(opts ...HandlerOption) Handler {
+	h := &autoHandler{}
+	h.Init(opts...)
+	return h
+}
+
+func (h *autoHandler) Init(options ...HandlerOption) {
+	if h.options == nil {
+		h.options = &HandlerOptions{}
+	}
+	for _, opt := range options {
+		opt(h.options)
+	}
+}
+
+func (h *autoHandler) Handle(conn net.Conn) {
+	br := bufio.NewReader(conn)
+	b, err := br.Peek(1)
+	if err != nil {
+		log.Logf("[auto] %s - %s: %s", conn.RemoteAddr(), conn.LocalAddr(), err)
+		conn.Close()
+		return
+	}
+
+	cc := &bufferdConn{Conn: conn, br: br}
+	var handler Handler
+	switch b[0] {
+	case gosocks4.Ver4:
+		// SOCKS4(a) does not suppport authentication method,
+		// so we ignore it when credentials are specified for security reason.
+		if len(h.options.Users) > 0 {
+			cc.Close()
+			return
+		}
+		handler = &socks4Handler{options: h.options}
+	case gosocks5.Ver5: // socks5
+		handler = &socks5Handler{options: h.options}
+	default: // http
+		handler = &httpHandler{options: h.options}
+	}
+	handler.Init()
+	handler.Handle(cc)
+}
+
+type bufferdConn struct {
+	net.Conn
+	br *bufio.Reader
+}
+
+func (c *bufferdConn) Read(b []byte) (int, error) {
+	return c.br.Read(b)
+}