Make captcha and password optional for external accounts (go-gitea#6606)

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

@@ -216,6 +216,9 @@ Values containing `#` or `;` must be quoted using `` ` `` or `"""`.
    Requires `Mailer` to be enabled.
 - `DISABLE_REGISTRATION`: **false**: Disable registration, after which only admin can create
    accounts for users.
+- `REQUIRE_EXTERNAL_REGISTRATION_PASSWORD`: **false**: Enable this to force externally created
+   accounts (via GitHub, OpenID Connect, etc) to create a password. Warning: enabling this will
+   decrease security, so you should only enable it if you know what you're doing.
 - `REQUIRE_SIGNIN_VIEW`: **false**: Enable this to force users to log in to view any page.
 - `ENABLE_NOTIFY_MAIL`: **false**: Enable this to send e-mail to watchers of a repository when
    something happens, like creating issues. Requires `Mailer` to be enabled.
@@ -225,6 +228,8 @@ Values containing `#` or `;` must be quoted using `` ` `` or `"""`.
 - `ENABLE_REVERSE_PROXY_EMAIL`: **false**: Enable this to allow to auto-registration with a
    provided email rather than a generated email.
 - `ENABLE_CAPTCHA`: **false**: Enable this to use captcha validation for registration.
+- `REQUIRE_EXTERNAL_REGISTRATION_CAPTCHA`: **false**: Enable this to force captcha validation
+   even for External Accounts (i.e. GitHub, OpenID Connect, etc). You must `ENABLE_CAPTCHA` also.
 - `CAPTCHA_TYPE`: **image**: \[image, recaptcha\]
 - `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.
@@ -419,7 +424,7 @@ NB: You must `REDIRECT_MACARON_LOG` and have `DISABLE_ROUTER_LOG` set to `false`
 
 ## Metrics (`metrics`)
 
-- `ENABLED`: **false**: Enables /metrics endpoint for prometheus. 
+- `ENABLED`: **false**: Enables /metrics endpoint for prometheus.
 - `TOKEN`: **\<empty\>**: You need to specify the token, if you want to include in the authorization the metrics . The same token need to be used in prometheus parameters `bearer_token` or `bearer_token_file`.
 
 ## API (`api`)

modules/auth/user_form.go

@@ -79,7 +79,7 @@ func (f *InstallForm) Validate(ctx *macaron.Context, errs binding.Errors) bindin
 type RegisterForm struct {
 	UserName           string `binding:"Required;AlphaDashDot;MaxSize(40)"`
 	Email              string `binding:"Required;Email;MaxSize(254)"`
-	Password           string `binding:"Required;MaxSize(255)"`
+	Password           string `binding:"MaxSize(255)"`
 	Retype             string
 	GRecaptchaResponse string `form:"g-recaptcha-response"`
 }
@@ -129,6 +129,7 @@ func (f *MustChangePasswordForm) Validate(ctx *macaron.Context, errs binding.Err
 // SignInForm form for signing in with user/password
 type SignInForm struct {
 	UserName string `binding:"Required;MaxSize(254)"`
+	// TODO remove required from password for SecondFactorAuthentication
 	Password string `binding:"Required;MaxSize(255)"`
 	Remember bool
 }

modules/setting/service.go

@@ -27,6 +27,8 @@ var Service struct {
 	EnableReverseProxyAutoRegister          bool
 	EnableReverseProxyEmail                 bool
 	EnableCaptcha                           bool
+	RequireExternalRegistrationCaptcha      bool
+	RequireExternalRegistrationPassword     bool
 	CaptchaType                             string
 	RecaptchaSecret                         string
 	RecaptchaSitekey                        string
@@ -61,6 +63,8 @@ func newService() {
 	Service.EnableReverseProxyAutoRegister = sec.Key("ENABLE_REVERSE_PROXY_AUTO_REGISTRATION").MustBool()
 	Service.EnableReverseProxyEmail = sec.Key("ENABLE_REVERSE_PROXY_EMAIL").MustBool()
 	Service.EnableCaptcha = sec.Key("ENABLE_CAPTCHA").MustBool(false)
+	Service.RequireExternalRegistrationCaptcha = sec.Key("REQUIRE_EXTERNAL_REGISTRATION_CAPTCHA").MustBool(Service.EnableCaptcha)
+	Service.RequireExternalRegistrationPassword = sec.Key("REQUIRE_EXTERNAL_REGISTRATION_PASSWORD").MustBool()
 	Service.CaptchaType = sec.Key("CAPTCHA_TYPE").MustString(ImageCaptcha)
 	Service.RecaptchaSecret = sec.Key("RECAPTCHA_SECRET").MustString("")
 	Service.RecaptchaSitekey = sec.Key("RECAPTCHA_SITEKEY").MustString("")

routers/user/auth.go

@@ -697,9 +697,10 @@ func oAuth2UserLoginCallback(loginSource *models.LoginSource, request *http.Requ
 
 // LinkAccount shows the page where the user can decide to login or create a new account
 func LinkAccount(ctx *context.Context) {
+	ctx.Data["DisablePassword"] = !setting.Service.RequireExternalRegistrationCaptcha || setting.Service.AllowOnlyExternalRegistration
 	ctx.Data["Title"] = ctx.Tr("link_account")
 	ctx.Data["LinkAccountMode"] = true
-	ctx.Data["EnableCaptcha"] = setting.Service.EnableCaptcha
+	ctx.Data["EnableCaptcha"] = setting.Service.EnableCaptcha && setting.Service.RequireExternalRegistrationCaptcha
 	ctx.Data["CaptchaType"] = setting.Service.CaptchaType
 	ctx.Data["RecaptchaURL"] = setting.Service.RecaptchaURL
 	ctx.Data["RecaptchaSitekey"] = setting.Service.RecaptchaSitekey
@@ -746,10 +747,11 @@ func LinkAccount(ctx *context.Context) {
 
 // LinkAccountPostSignIn handle the coupling of external account with another account using signIn
 func LinkAccountPostSignIn(ctx *context.Context, signInForm auth.SignInForm) {
+	ctx.Data["DisablePassword"] = setting.Service.AllowOnlyExternalRegistration
 	ctx.Data["Title"] = ctx.Tr("link_account")
 	ctx.Data["LinkAccountMode"] = true
 	ctx.Data["LinkAccountModeSignIn"] = true
-	ctx.Data["EnableCaptcha"] = setting.Service.EnableCaptcha
+	ctx.Data["EnableCaptcha"] = setting.Service.EnableCaptcha && setting.Service.RequireExternalRegistrationCaptcha
 	ctx.Data["RecaptchaURL"] = setting.Service.RecaptchaURL
 	ctx.Data["CaptchaType"] = setting.Service.CaptchaType
 	ctx.Data["RecaptchaSitekey"] = setting.Service.RecaptchaSitekey
@@ -824,10 +826,13 @@ func LinkAccountPostSignIn(ctx *context.Context, signInForm auth.SignInForm) {
 
 // LinkAccountPostRegister handle the creation of a new account for an external account using signUp
 func LinkAccountPostRegister(ctx *context.Context, cpt *captcha.Captcha, form auth.RegisterForm) {
+	// TODO Make insecure passwords optional for local accounts also,
+	//      once email-based Second-Factor Auth is available
+	ctx.Data["DisablePassword"] = !setting.Service.RequireExternalRegistrationCaptcha || setting.Service.AllowOnlyExternalRegistration
 	ctx.Data["Title"] = ctx.Tr("link_account")
 	ctx.Data["LinkAccountMode"] = true
 	ctx.Data["LinkAccountModeRegister"] = true
-	ctx.Data["EnableCaptcha"] = setting.Service.EnableCaptcha
+	ctx.Data["EnableCaptcha"] = setting.Service.EnableCaptcha && setting.Service.RequireExternalRegistrationCaptcha
 	ctx.Data["RecaptchaURL"] = setting.Service.RecaptchaURL
 	ctx.Data["CaptchaType"] = setting.Service.CaptchaType
 	ctx.Data["RecaptchaSitekey"] = setting.Service.RecaptchaSitekey
@@ -854,30 +859,43 @@ func LinkAccountPostRegister(ctx *context.Context, cpt *captcha.Captcha, form au
 		return
 	}
 
-	if setting.Service.EnableCaptcha && setting.Service.CaptchaType == setting.ImageCaptcha && !cpt.VerifyReq(ctx.Req) {
-		ctx.Data["Err_Captcha"] = true
-		ctx.RenderWithErr(ctx.Tr("form.captcha_incorrect"), tplLinkAccount, &form)
-		return
-	}
+	if setting.Service.EnableCaptcha && setting.Service.RequireExternalRegistrationCaptcha {
+		var valid bool
+		switch setting.Service.CaptchaType {
+		case setting.ImageCaptcha:
+			valid = cpt.VerifyReq(ctx.Req)
+		case setting.ReCaptcha:
+			valid, _ = recaptcha.Verify(form.GRecaptchaResponse)
+		default:
+			ctx.ServerError("Unknown Captcha Type", fmt.Errorf("Unknown Captcha Type: %s", setting.Service.CaptchaType))
+			return
+		}
 
-	if setting.Service.EnableCaptcha && setting.Service.CaptchaType == setting.ReCaptcha {
-		valid, _ := recaptcha.Verify(form.GRecaptchaResponse)
 		if !valid {
 			ctx.Data["Err_Captcha"] = true
 			ctx.RenderWithErr(ctx.Tr("form.captcha_incorrect"), tplLinkAccount, &form)
 			return
 		}
 	}
 
-	if (len(strings.TrimSpace(form.Password)) > 0 || len(strings.TrimSpace(form.Retype)) > 0) && form.Password != form.Retype {
-		ctx.Data["Err_Password"] = true
-		ctx.RenderWithErr(ctx.Tr("form.password_not_match"), tplLinkAccount, &form)
-		return
-	}
-	if len(strings.TrimSpace(form.Password)) > 0 && len(form.Password) < setting.MinPasswordLength {
-		ctx.Data["Err_Password"] = true
-		ctx.RenderWithErr(ctx.Tr("auth.password_too_short", setting.MinPasswordLength), tplLinkAccount, &form)
-		return
+	if setting.Service.AllowOnlyExternalRegistration || !setting.Service.RequireExternalRegistrationPassword {
+		// In models.User an empty password is classed as not set, so we set form.Password to empty.
+		// Eventually the database should be changed to indicate "Second Factor"-enabled accounts
+		// (accounts that do not introduce the security vulnerabilities of a password).
+		// If a user decides to circumvent second-factor security, and purposefully create a password,
+		// they can still do so using the "Recover Account" option.
+		form.Password = ""
+	} else {
+		if (len(strings.TrimSpace(form.Password)) > 0 || len(strings.TrimSpace(form.Retype)) > 0) && form.Password != form.Retype {
+			ctx.Data["Err_Password"] = true
+			ctx.RenderWithErr(ctx.Tr("form.password_not_match"), tplLinkAccount, &form)
+			return
+		}
+		if len(strings.TrimSpace(form.Password)) > 0 && len(form.Password) < setting.MinPasswordLength {
+			ctx.Data["Err_Password"] = true
+			ctx.RenderWithErr(ctx.Tr("auth.password_too_short", setting.MinPasswordLength), tplLinkAccount, &form)
+			return
+		}
 	}
 
 	loginSource, err := models.GetActiveOAuth2LoginSourceByName(gothUser.(goth.User).Provider)
@@ -1000,14 +1018,18 @@ func SignUpPost(ctx *context.Context, cpt *captcha.Captcha, form auth.RegisterFo
 		return
 	}
 
-	if setting.Service.EnableCaptcha && setting.Service.CaptchaType == setting.ImageCaptcha && !cpt.VerifyReq(ctx.Req) {
-		ctx.Data["Err_Captcha"] = true
-		ctx.RenderWithErr(ctx.Tr("form.captcha_incorrect"), tplSignUp, &form)
-		return
-	}
+	if setting.Service.EnableCaptcha {
+		var valid bool
+		switch setting.Service.CaptchaType {
+		case setting.ImageCaptcha:
+			valid = cpt.VerifyReq(ctx.Req)
+		case setting.ReCaptcha:
+			valid, _ = recaptcha.Verify(form.GRecaptchaResponse)
+		default:
+			ctx.ServerError("Unknown Captcha Type", fmt.Errorf("Unknown Captcha Type: %s", setting.Service.CaptchaType))
+			return
+		}
 
-	if setting.Service.EnableCaptcha && setting.Service.CaptchaType == setting.ReCaptcha {
-		valid, _ := recaptcha.Verify(form.GRecaptchaResponse)
 		if !valid {
 			ctx.Data["Err_Captcha"] = true
 			ctx.RenderWithErr(ctx.Tr("form.captcha_incorrect"), tplSignUp, &form)

routers/user/auth_openid.go

@@ -357,19 +357,23 @@ func RegisterOpenIDPost(ctx *context.Context, cpt *captcha.Captcha, form auth.Si
 	ctx.Data["RecaptchaSitekey"] = setting.Service.RecaptchaSitekey
 	ctx.Data["OpenID"] = oid
 
-	if setting.Service.EnableCaptcha && setting.Service.CaptchaType == setting.ImageCaptcha && !cpt.VerifyReq(ctx.Req) {
-		ctx.Data["Err_Captcha"] = true
-		ctx.RenderWithErr(ctx.Tr("form.captcha_incorrect"), tplSignUpOID, &form)
-		return
-	}
-
-	if setting.Service.EnableCaptcha && setting.Service.CaptchaType == setting.ReCaptcha {
-		err := ctx.Req.ParseForm()
-		if err != nil {
-			ctx.ServerError("", err)
+	if setting.Service.EnableCaptcha {
+		var valid bool
+		switch setting.Service.CaptchaType {
+		case setting.ImageCaptcha:
+			valid = cpt.VerifyReq(ctx.Req)
+		case setting.ReCaptcha:
+			err := ctx.Req.ParseForm()
+			if err != nil {
+				ctx.ServerError("", err)
+				return
+			}
+			valid, _ = recaptcha.Verify(form.GRecaptchaResponse)
+		default:
+			ctx.ServerError("Unknown Captcha Type", fmt.Errorf("Unknown Captcha Type: %s", setting.Service.CaptchaType))
 			return
 		}
-		valid, _ := recaptcha.Verify(form.GRecaptchaResponse)
+
 		if !valid {
 			ctx.Data["Err_Captcha"] = true
 			ctx.RenderWithErr(ctx.Tr("form.captcha_incorrect"), tplSignUpOID, &form)

templates/user/auth/signin_inner.tmpl

@@ -15,10 +15,12 @@
 				<label for="user_name">{{.i18n.Tr "home.uname_holder"}}</label>
 				<input id="user_name" name="user_name" value="{{.user_name}}" autofocus required>
 			</div>
+			{{if not .DisablePassword}}
 			<div class="required inline field {{if and (.Err_Password) (or (not .LinkAccountMode) (and .LinkAccountMode .LinkAccountModeSignIn))}}error{{end}}">
 				<label for="password">{{.i18n.Tr "password"}}</label>
 				<input id="password" name="password" type="password" value="{{.password}}" autocomplete="off" required>
 			</div>
+			{{end}}
 			{{if not .LinkAccountMode}}
 			<div class="inline field">
 				<label></label>

templates/user/auth/signup_inner.tmpl

@@ -25,14 +25,17 @@
 							<label for="email">{{.i18n.Tr "email"}}</label>
 							<input id="email" name="email" type="email" value="{{.email}}" required>
 						</div>
-						<div class="required inline field {{if and (.Err_Password) (or (not .LinkAccountMode) (and .LinkAccountMode .LinkAccountModeRegister))}}error{{end}}">
-							<label for="password">{{.i18n.Tr "password"}}</label>
-							<input id="password" name="password" type="password" value="{{.password}}" autocomplete="off" required>
-						</div>
-						<div class="required inline field {{if and (.Err_Password) (or (not .LinkAccountMode) (and .LinkAccountMode .LinkAccountModeRegister))}}error{{end}}">
-							<label for="retype">{{.i18n.Tr "re_type"}}</label>
-							<input id="retype" name="retype" type="password" value="{{.retype}}" autocomplete="off" required>
-						</div>
+
+						{{if not .DisablePassword}}
+							<div class="required inline field {{if and (.Err_Password) (or (not .LinkAccountMode) (and .LinkAccountMode .LinkAccountModeRegister))}}error{{end}}">
+								<label for="password">{{.i18n.Tr "password"}}</label>
+								<input id="password" name="password" type="password" value="{{.password}}" autocomplete="off" required>
+							</div>
+							<div class="required inline field {{if and (.Err_Password) (or (not .LinkAccountMode) (and .LinkAccountMode .LinkAccountModeRegister))}}error{{end}}">
+								<label for="retype">{{.i18n.Tr "re_type"}}</label>
+								<input id="retype" name="retype" type="password" value="{{.retype}}" autocomplete="off" required>
+							</div>
+						{{end}}
 						{{if and .EnableCaptcha (eq .CaptchaType "image")}}
 							<div class="inline field">
 								<label></label>