Add SSH sniffer

common/sniff/ssh.go

@@ -0,0 +1,26 @@
+package sniff
+
+import (
+	"bufio"
+	"context"
+	"io"
+	"os"
+	"strings"
+
+	"github.com/sagernet/sing-box/adapter"
+	C "github.com/sagernet/sing-box/constant"
+)
+
+func SSH(_ context.Context, metadata *adapter.InboundContext, reader io.Reader) error {
+	scanner := bufio.NewScanner(reader)
+	if !scanner.Scan() {
+		return os.ErrInvalid
+	}
+	fistLine := scanner.Text()
+	if !strings.HasPrefix(fistLine, "SSH-2.0-") {
+		return os.ErrInvalid
+	}
+	metadata.Protocol = C.ProtocolSSH
+	metadata.Client = fistLine[8:]
+	return nil
+}