实现WAF

internal/waf/action_captcha.go

@@ -0,0 +1,39 @@
+package waf
+
+import (
+	"github.com/TeaOSLab/EdgeNode/internal/waf/requests"
+	"github.com/iwind/TeaGo/types"
+	stringutil "github.com/iwind/TeaGo/utils/string"
+	"net/http"
+	"net/url"
+	"time"
+)
+
+var captchaSalt = stringutil.Rand(32)
+
+const (
+	CaptchaSeconds = 600 // 10 minutes
+)
+
+type CaptchaAction struct {
+}
+
+func (this *CaptchaAction) Perform(waf *WAF, request *requests.Request, writer http.ResponseWriter) (allow bool) {
+	// TEAWEB_CAPTCHA:
+	cookie, err := request.Cookie("TEAWEB_WAF_CAPTCHA")
+	if err == nil && cookie != nil && len(cookie.Value) > 32 {
+		m := cookie.Value[:32]
+		timestamp := cookie.Value[32:]
+		if stringutil.Md5(captchaSalt+timestamp) == m && time.Now().Unix() < types.Int64(timestamp) { // verify md5
+			return true
+		}
+	}
+
+	refURL := request.URL.String()
+	if len(request.Referer()) > 0 {
+		refURL = request.Referer()
+	}
+	http.Redirect(writer, request.Raw(), "/WAFCAPTCHA?url="+url.QueryEscape(refURL), http.StatusTemporaryRedirect)
+
+	return false
+}