v1.0.0

common/protocol/http/sniff.go

@@ -0,0 +1,94 @@
+package http
+
+import (
+	"bytes"
+	"errors"
+	"strings"
+
+	"github.com/xtls/xray-core/v1/common"
+	"github.com/xtls/xray-core/v1/common/net"
+)
+
+type version byte
+
+const (
+	HTTP1 version = iota
+	HTTP2
+)
+
+type SniffHeader struct {
+	version version
+	host    string
+}
+
+func (h *SniffHeader) Protocol() string {
+	switch h.version {
+	case HTTP1:
+		return "http1"
+	case HTTP2:
+		return "http2"
+	default:
+		return "unknown"
+	}
+}
+
+func (h *SniffHeader) Domain() string {
+	return h.host
+}
+
+var (
+	methods = [...]string{"get", "post", "head", "put", "delete", "options", "connect"}
+
+	errNotHTTPMethod = errors.New("not an HTTP method")
+)
+
+func beginWithHTTPMethod(b []byte) error {
+	for _, m := range &methods {
+		if len(b) >= len(m) && strings.EqualFold(string(b[:len(m)]), m) {
+			return nil
+		}
+
+		if len(b) < len(m) {
+			return common.ErrNoClue
+		}
+	}
+
+	return errNotHTTPMethod
+}
+
+func SniffHTTP(b []byte) (*SniffHeader, error) {
+	if err := beginWithHTTPMethod(b); err != nil {
+		return nil, err
+	}
+
+	sh := &SniffHeader{
+		version: HTTP1,
+	}
+
+	headers := bytes.Split(b, []byte{'\n'})
+	for i := 1; i < len(headers); i++ {
+		header := headers[i]
+		if len(header) == 0 {
+			break
+		}
+		parts := bytes.SplitN(header, []byte{':'}, 2)
+		if len(parts) != 2 {
+			continue
+		}
+		key := strings.ToLower(string(parts[0]))
+		if key == "host" {
+			rawHost := strings.ToLower(string(bytes.TrimSpace(parts[1])))
+			dest, err := ParseHost(rawHost, net.Port(80))
+			if err != nil {
+				return nil, err
+			}
+			sh.host = dest.Address.String()
+		}
+	}
+
+	if len(sh.host) > 0 {
+		return sh, nil
+	}
+
+	return nil, common.ErrNoClue
+}