Add new captcha: cloudflare turnstile

custom/conf/app.example.ini

@@ -765,7 +765,7 @@ ROUTER = console
 ;; Enable this to require captcha validation for login
 ;REQUIRE_CAPTCHA_FOR_LOGIN = false
 ;;
-;; Type of captcha you want to use. Options: image, recaptcha, hcaptcha, mcaptcha.
+;; Type of captcha you want to use. Options: image, recaptcha, hcaptcha, mcaptcha, cfturnstile.
 ;CAPTCHA_TYPE = image
 ;;
 ;; Change this to use recaptcha.net or other recaptcha service
@@ -787,6 +787,11 @@ ROUTER = console
 ;MCAPTCHA_SECRET =
 ;MCAPTCHA_SITEKEY =
 ;;
+;; Go to https://dash.cloudflare.com/?to=/:account/turnstile to sign up for a key
+;CF_TURNSTILE_SITEKEY =
+;CF_TURNSTILE_SECRET =
+;CF_REVERSE_PROXY_HEADER =
+;;
 ;; Default value for KeepEmailPrivate
 ;; Each new user will get the value of this setting copied into their profile
 ;DEFAULT_KEEP_EMAIL_PRIVATE = false

docs/content/doc/advanced/config-cheat-sheet.en-us.md

@@ -644,7 +644,7 @@ Certain queues have defaults that override the defaults set in `[queue]` (this o
 - `REQUIRE_CAPTCHA_FOR_LOGIN`: **false**: Enable this to require captcha validation for login. You also must enable `ENABLE_CAPTCHA`.
 - `REQUIRE_EXTERNAL_REGISTRATION_CAPTCHA`: **false**: Enable this to force captcha validation
    even for External Accounts (i.e. GitHub, OpenID Connect, etc). You also must enable `ENABLE_CAPTCHA`.
-- `CAPTCHA_TYPE`: **image**: \[image, recaptcha, hcaptcha, mcaptcha\]
+- `CAPTCHA_TYPE`: **image**: \[image, recaptcha, hcaptcha, mcaptcha, cfturnstile\]
 - `RECAPTCHA_SECRET`: **""**: Go to https://www.google.com/recaptcha/admin to get a secret for recaptcha.
 - `RECAPTCHA_SITEKEY`: **""**: Go to https://www.google.com/recaptcha/admin to get a sitekey for recaptcha.
 - `RECAPTCHA_URL`: **https://www.google.com/recaptcha/**: Set the recaptcha url - allows the use of recaptcha net.
@@ -653,6 +653,9 @@ Certain queues have defaults that override the defaults set in `[queue]` (this o
 - `MCAPTCHA_SECRET`: **""**: Go to your mCaptcha instance to get a secret for mCaptcha.
 - `MCAPTCHA_SITEKEY`: **""**: Go to your mCaptcha instance to get a sitekey for mCaptcha.
 - `MCAPTCHA_URL` **https://demo.mcaptcha.org/**: Set the mCaptcha URL.
+- `CF_TURNSTILE_SECRET` **""**: Go to https://dash.cloudflare.com/?to=/:account/turnstile to get a secret for cloudflare turnstile.
+- `CF_TURNSTILE_SITEKEY` **""**: Go to https://dash.cloudflare.com/?to=/:account/turnstile to get a sitekey for cloudflare turnstile.
+- `CF_REVERSE_PROXY_HEADER` **""**: The http header where the user's real ip is located. Otherwise it should be `""`.
 - `DEFAULT_KEEP_EMAIL_PRIVATE`: **false**: By default set users to keep their email address private.
 - `DEFAULT_ALLOW_CREATE_ORGANIZATION`: **true**: Allow new users to create organizations by default.
 - `DEFAULT_USER_IS_RESTRICTED`: **false**: Give new users restricted permissions by default

docs/content/doc/advanced/config-cheat-sheet.zh-cn.md

@@ -147,6 +147,18 @@ menu:
 - `ENABLE_REVERSE_PROXY_AUTO_REGISTRATION`: 允许通过反向认证做自动注册。
 - `ENABLE_CAPTCHA`: **false**: 注册时使用图片验证码。
 - `REQUIRE_CAPTCHA_FOR_LOGIN`: **false**: 登录时需要图片验证码。需要同时开启 `ENABLE_CAPTCHA`。
+- `CAPTCHA_TYPE`: **image**: \[image, recaptcha, hcaptcha, mcaptcha, cfturnstile\]，人机验证类型，分别表示图片认证、 recaptcha 、 hcaptcha 、mcaptcha 、和 cloudlfare 的 turnstile。
+- `RECAPTCHA_SECRET`: **""**: recaptcha 服务的密钥，可在 https://www.google.com/recaptcha/admin 获取。
+- `RECAPTCHA_SITEKEY`: **""**: recaptcha 服务的网站密钥 ，可在 https://www.google.com/recaptcha/admin 获取。
+- `RECAPTCHA_URL`: **https://www.google.com/recaptcha/**: 设置 recaptcha 的 url 。
+- `HCAPTCHA_SECRET`: **""**: hcaptcha 服务的密钥，可在 https://www.hcaptcha.com/ 获取。
+- `HCAPTCHA_SITEKEY`: **""**: hcaptcha 服务的网站密钥，可在 https://www.hcaptcha.com/ 获取。
+- `MCAPTCHA_SECRET`: **""**: mCaptcha 服务的密钥。
+- `MCAPTCHA_SITEKEY`: **""**: mCaptcha 服务的网站密钥。
+- `MCAPTCHA_URL` **https://demo.mcaptcha.org/**: 设置 remCaptchacaptcha 的 url 。
+- `CF_TURNSTILE_SECRET` **""**: cloudlfare turnstile 服务的密钥，可在 https://dash.cloudflare.com/?to=/:account/turnstile 获取。
+- `CF_TURNSTILE_SITEKEY` **""**: cloudlfare turnstile 服务的网站密钥 ，可在 https://www.google.com/recaptcha/admin 获取。
+- `CF_REVERSE_PROXY_HEADER` **""**: http 的 header 字段，用于获取客户端的 ip 供 cloudflare turnstile 验证时使用。如果没有反向代理设置这里应设置为 `""` 。
 
 ### Service - Expore (`service.explore`)
 

modules/context/captcha.go

@@ -14,6 +14,7 @@ import (
 	"code.gitea.io/gitea/modules/mcaptcha"
 	"code.gitea.io/gitea/modules/recaptcha"
 	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/turnstile"
 
 	"gitea.com/go-chi/captcha"
 )
@@ -47,12 +48,14 @@ func SetCaptchaData(ctx *Context) {
 	ctx.Data["HcaptchaSitekey"] = setting.Service.HcaptchaSitekey
 	ctx.Data["McaptchaSitekey"] = setting.Service.McaptchaSitekey
 	ctx.Data["McaptchaURL"] = setting.Service.McaptchaURL
+	ctx.Data["CfTurnstileSitekey"] = setting.Service.CfTurnstileSitekey
 }
 
 const (
-	gRecaptchaResponseField = "g-recaptcha-response"
-	hCaptchaResponseField   = "h-captcha-response"
-	mCaptchaResponseField   = "m-captcha-response"
+	gRecaptchaResponseField  = "g-recaptcha-response"
+	hCaptchaResponseField    = "h-captcha-response"
+	mCaptchaResponseField    = "m-captcha-response"
+	cfTurnstileResponseField = "cf-turnstile-response"
 )
 
 // VerifyCaptcha verifies Captcha data
@@ -73,6 +76,14 @@ func VerifyCaptcha(ctx *Context, tpl base.TplName, form interface{}) {
 		valid, err = hcaptcha.Verify(ctx, ctx.Req.Form.Get(hCaptchaResponseField))
 	case setting.MCaptcha:
 		valid, err = mcaptcha.Verify(ctx, ctx.Req.Form.Get(mCaptchaResponseField))
+	case setting.CfTurnstile:
+		var ip string
+		if setting.Service.CfReverseProxyHeader == "" {
+			ip = ctx.RemoteAddr()
+		} else {
+			ip = ctx.Req.Header.Get(setting.Service.CfReverseProxyHeader)
+		}
+		valid, err = turnstile.Verify(ctx, ctx.Req.Form.Get(cfTurnstileResponseField), ip)
 	default:
 		ctx.ServerError("Unknown Captcha Type", fmt.Errorf("Unknown Captcha Type: %s", setting.Service.CaptchaType))
 		return

modules/setting/service.go

@@ -46,6 +46,9 @@ var Service = struct {
 	RecaptchaSecret                         string
 	RecaptchaSitekey                        string
 	RecaptchaURL                            string
+	CfTurnstileSecret                       string
+	CfTurnstileSitekey                      string
+	CfReverseProxyHeader                    string
 	HcaptchaSecret                          string
 	HcaptchaSitekey                         string
 	McaptchaSecret                          string
@@ -137,6 +140,9 @@ func newService() {
 	Service.RecaptchaSecret = sec.Key("RECAPTCHA_SECRET").MustString("")
 	Service.RecaptchaSitekey = sec.Key("RECAPTCHA_SITEKEY").MustString("")
 	Service.RecaptchaURL = sec.Key("RECAPTCHA_URL").MustString("https://www.google.com/recaptcha/")
+	Service.CfTurnstileSecret = sec.Key("CF_TURNSTILE_SECRET").MustString("")
+	Service.CfTurnstileSitekey = sec.Key("CF_TURNSTILE_SITEKEY").MustString("")
+	Service.CfReverseProxyHeader = sec.Key("CF_REVERSE_PROXY_HEADER").MustString("")
 	Service.HcaptchaSecret = sec.Key("HCAPTCHA_SECRET").MustString("")
 	Service.HcaptchaSitekey = sec.Key("HCAPTCHA_SITEKEY").MustString("")
 	Service.McaptchaURL = sec.Key("MCAPTCHA_URL").MustString("https://demo.mcaptcha.org/")

modules/setting/setting.go

@@ -60,6 +60,7 @@ const (
 	ReCaptcha    = "recaptcha"
 	HCaptcha     = "hcaptcha"
 	MCaptcha     = "mcaptcha"
+	CfTurnstile  = "cfturnstile"
 )
 
 // settings

modules/turnstile/turnstile.go

@@ -0,0 +1,93 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package turnstile
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+
+	"code.gitea.io/gitea/modules/json"
+	"code.gitea.io/gitea/modules/setting"
+)
+
+// Response is the structure of JSON returned from API
+type Response struct {
+	Success     bool        `json:"success"`
+	ChallengeTS string      `json:"challenge_ts"`
+	Hostname    string      `json:"hostname"`
+	ErrorCodes  []ErrorCode `json:"error-codes"`
+	Action      string      `json:"login"`
+	Cdata       string      `json:"cdata"`
+}
+
+// Verify calls Cloudflare Turnstile API to verify token
+func Verify(ctx context.Context, response, ip string) (bool, error) {
+	// Cloudflare turnstile official access instruction address: https://developers.cloudflare.com/turnstile/get-started/server-side-validation/
+	post := url.Values{
+		"secret":   {setting.Service.CfTurnstileSecret},
+		"response": {response},
+		"remoteip": {ip},
+	}
+	// Basically a copy of http.PostForm, but with a context
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost,
+		"https://challenges.cloudflare.com/turnstile/v0/siteverify", strings.NewReader(post.Encode()))
+	if err != nil {
+		return false, fmt.Errorf("Failed to create CAPTCHA request: %w", err)
+	}
+	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return false, fmt.Errorf("Failed to send CAPTCHA response: %s", err)
+	}
+	defer resp.Body.Close()
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return false, fmt.Errorf("Failed to read CAPTCHA response: %s", err)
+	}
+
+	var jsonResponse Response
+	err = json.Unmarshal(body, &jsonResponse)
+	if err != nil {
+		return false, fmt.Errorf("Failed to parse CAPTCHA response: %s", err)
+	}
+	var respErr error
+	if len(jsonResponse.ErrorCodes) > 0 {
+		respErr = jsonResponse.ErrorCodes[0]
+	}
+	return jsonResponse.Success, respErr
+}
+
+// ErrorCode is a reCaptcha error
+type ErrorCode string
+
+// String fulfills the Stringer interface
+func (e ErrorCode) String() string {
+	switch e {
+	case "missing-input-secret":
+		return "The secret parameter was not passed."
+	case "invalid-input-secret":
+		return "The secret parameter was invalid or did not exist."
+	case "missing-input-response":
+		return "The response parameter was not passed."
+	case "invalid-input-response":
+		return "The response parameter is invalid or has expired."
+	case "bad-request":
+		return "The request was rejected because it was malformed."
+	case "timeout-or-duplicate":
+		return "The response parameter has already been validated before."
+	case "internal-error":
+		return "An internal error happened while validating the response. The request can be retried."
+	}
+	return string(e)
+}
+
+// Error fulfills the error interface
+func (e ErrorCode) Error() string {
+	return e.String()
+}

templates/base/footer.tmpl

@@ -21,6 +21,9 @@
 	{{if eq .CaptchaType "hcaptcha"}}
 		<script src='https://hcaptcha.com/1/api.js' async></script>
 	{{end}}
+	{{if eq .CaptchaType "cfturnstile"}}
+		<script src='https://challenges.cloudflare.com/turnstile/v0/api.js' async defer></script>
+	{{end}}
 {{end}}
 	<script src="{{AssetUrlPrefix}}/js/index.js?v={{AssetVersion}}" onerror="alert('Failed to load asset files from ' + this.src + ', please make sure the asset files can be accessed and the ROOT_URL setting in app.ini is correct.')"></script>
 {{template "custom/footer" .}}

templates/user/auth/captcha.tmpl

@@ -21,4 +21,8 @@
 		<div class="border-secondary w-100-small" id="mcaptcha__widget-container" style="width: 50%; height: 5em"></div>
 		<div class="m-captcha" data-sitekey="{{.McaptchaSitekey}}" data-instance-url="{{.McaptchaURL}}"></div>
 	</div>
+{{else if eq .CaptchaType "cfturnstile"}}
+	<div class="inline field captcha-field tc">
+		<div class="cf-turnstile" data-sitekey="{{.CfTurnstileSitekey}}"></div>
+	</div>
 {{end}}{{end}}