Refactor routers directory (#15800)

* refactor routers directory

* move func used for web and api to common

* make corsHandler a function to prohibit side efects

* rm unused func

Co-authored-by: 6543 <6543@obermui.de>

1 files changed, 1769 insertions, 0 deletions

diff --git a/routers/web/user/auth.go b/routers/web/user/auth.go
new file mode 100644
index 0000000000..827b7cdef0
--- /dev/null
+++ b/routers/web/user/auth.go
@@ -0,0 +1,1769 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Copyright 2018 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package user
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"strings"
+
+	"code.gitea.io/gitea/models"
+	"code.gitea.io/gitea/modules/auth/oauth2"
+	"code.gitea.io/gitea/modules/base"
+	"code.gitea.io/gitea/modules/context"
+	"code.gitea.io/gitea/modules/eventsource"
+	"code.gitea.io/gitea/modules/hcaptcha"
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/password"
+	"code.gitea.io/gitea/modules/recaptcha"
+	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/timeutil"
+	"code.gitea.io/gitea/modules/web"
+	"code.gitea.io/gitea/modules/web/middleware"
+	"code.gitea.io/gitea/routers/utils"
+	"code.gitea.io/gitea/services/externalaccount"
+	"code.gitea.io/gitea/services/forms"
+	"code.gitea.io/gitea/services/mailer"
+
+	"github.com/markbates/goth"
+	"github.com/tstranex/u2f"
+)
+
+const (
+	// tplMustChangePassword template for updating a user's password
+	tplMustChangePassword = "user/auth/change_passwd"
+	// tplSignIn template for sign in page
+	tplSignIn base.TplName = "user/auth/signin"
+	// tplSignUp template path for sign up page
+	tplSignUp base.TplName = "user/auth/signup"
+	// TplActivate template path for activate user
+	TplActivate       base.TplName = "user/auth/activate"
+	tplForgotPassword base.TplName = "user/auth/forgot_passwd"
+	tplResetPassword  base.TplName = "user/auth/reset_passwd"
+	tplTwofa          base.TplName = "user/auth/twofa"
+	tplTwofaScratch   base.TplName = "user/auth/twofa_scratch"
+	tplLinkAccount    base.TplName = "user/auth/link_account"
+	tplU2F            base.TplName = "user/auth/u2f"
+)
+
+// AutoSignIn reads cookie and try to auto-login.
+func AutoSignIn(ctx *context.Context) (bool, error) {
+	if !models.HasEngine {
+		return false, nil
+	}
+
+	uname := ctx.GetCookie(setting.CookieUserName)
+	if len(uname) == 0 {
+		return false, nil
+	}
+
+	isSucceed := false
+	defer func() {
+		if !isSucceed {
+			log.Trace("auto-login cookie cleared: %s", uname)
+			ctx.DeleteCookie(setting.CookieUserName)
+			ctx.DeleteCookie(setting.CookieRememberName)
+		}
+	}()
+
+	u, err := models.GetUserByName(uname)
+	if err != nil {
+		if !models.IsErrUserNotExist(err) {
+			return false, fmt.Errorf("GetUserByName: %v", err)
+		}
+		return false, nil
+	}
+
+	if val, ok := ctx.GetSuperSecureCookie(
+		base.EncodeMD5(u.Rands+u.Passwd), setting.CookieRememberName); !ok || val != u.Name {
+		return false, nil
+	}
+
+	isSucceed = true
+
+	// Set session IDs
+	if err := ctx.Session.Set("uid", u.ID); err != nil {
+		return false, err
+	}
+	if err := ctx.Session.Set("uname", u.Name); err != nil {
+		return false, err
+	}
+	if err := ctx.Session.Release(); err != nil {
+		return false, err
+	}
+
+	middleware.DeleteCSRFCookie(ctx.Resp)
+	return true, nil
+}
+
+func checkAutoLogin(ctx *context.Context) bool {
+	// Check auto-login.
+	isSucceed, err := AutoSignIn(ctx)
+	if err != nil {
+		ctx.ServerError("AutoSignIn", err)
+		return true
+	}
+
+	redirectTo := ctx.Query("redirect_to")
+	if len(redirectTo) > 0 {
+		middleware.SetRedirectToCookie(ctx.Resp, redirectTo)
+	} else {
+		redirectTo = ctx.GetCookie("redirect_to")
+	}
+
+	if isSucceed {
+		middleware.DeleteRedirectToCookie(ctx.Resp)
+		ctx.RedirectToFirst(redirectTo, setting.AppSubURL+string(setting.LandingPageURL))
+		return true
+	}
+
+	return false
+}
+
+// SignIn render sign in page
+func SignIn(ctx *context.Context) {
+	ctx.Data["Title"] = ctx.Tr("sign_in")
+
+	// Check auto-login.
+	if checkAutoLogin(ctx) {
+		return
+	}
+
+	orderedOAuth2Names, oauth2Providers, err := models.GetActiveOAuth2Providers()
+	if err != nil {
+		ctx.ServerError("UserSignIn", err)
+		return
+	}
+	ctx.Data["OrderedOAuth2Names"] = orderedOAuth2Names
+	ctx.Data["OAuth2Providers"] = oauth2Providers
+	ctx.Data["Title"] = ctx.Tr("sign_in")
+	ctx.Data["SignInLink"] = setting.AppSubURL + "/user/login"
+	ctx.Data["PageIsSignIn"] = true
+	ctx.Data["PageIsLogin"] = true
+	ctx.Data["EnableSSPI"] = models.IsSSPIEnabled()
+
+	ctx.HTML(http.StatusOK, tplSignIn)
+}
+
+// SignInPost response for sign in request
+func SignInPost(ctx *context.Context) {
+	ctx.Data["Title"] = ctx.Tr("sign_in")
+
+	orderedOAuth2Names, oauth2Providers, err := models.GetActiveOAuth2Providers()
+	if err != nil {
+		ctx.ServerError("UserSignIn", err)
+		return
+	}
+	ctx.Data["OrderedOAuth2Names"] = orderedOAuth2Names
+	ctx.Data["OAuth2Providers"] = oauth2Providers
+	ctx.Data["Title"] = ctx.Tr("sign_in")
+	ctx.Data["SignInLink"] = setting.AppSubURL + "/user/login"
+	ctx.Data["PageIsSignIn"] = true
+	ctx.Data["PageIsLogin"] = true
+	ctx.Data["EnableSSPI"] = models.IsSSPIEnabled()
+
+	if ctx.HasError() {
+		ctx.HTML(http.StatusOK, tplSignIn)
+		return
+	}
+
+	form := web.GetForm(ctx).(*forms.SignInForm)
+	u, err := models.UserSignIn(form.UserName, form.Password)
+	if err != nil {
+		if models.IsErrUserNotExist(err) {
+			ctx.RenderWithErr(ctx.Tr("form.username_password_incorrect"), tplSignIn, &form)
+			log.Info("Failed authentication attempt for %s from %s: %v", form.UserName, ctx.RemoteAddr(), err)
+		} else if models.IsErrEmailAlreadyUsed(err) {
+			ctx.RenderWithErr(ctx.Tr("form.email_been_used"), tplSignIn, &form)
+			log.Info("Failed authentication attempt for %s from %s: %v", form.UserName, ctx.RemoteAddr(), err)
+		} else if models.IsErrUserProhibitLogin(err) {
+			log.Info("Failed authentication attempt for %s from %s: %v", form.UserName, ctx.RemoteAddr(), err)
+			ctx.Data["Title"] = ctx.Tr("auth.prohibit_login")
+			ctx.HTML(http.StatusOK, "user/auth/prohibit_login")
+		} else if models.IsErrUserInactive(err) {
+			if setting.Service.RegisterEmailConfirm {
+				ctx.Data["Title"] = ctx.Tr("auth.active_your_account")
+				ctx.HTML(http.StatusOK, TplActivate)
+			} else {
+				log.Info("Failed authentication attempt for %s from %s: %v", form.UserName, ctx.RemoteAddr(), err)
+				ctx.Data["Title"] = ctx.Tr("auth.prohibit_login")
+				ctx.HTML(http.StatusOK, "user/auth/prohibit_login")
+			}
+		} else {
+			ctx.ServerError("UserSignIn", err)
+		}
+		return
+	}
+	// If this user is enrolled in 2FA, we can't sign the user in just yet.
+	// Instead, redirect them to the 2FA authentication page.
+	_, err = models.GetTwoFactorByUID(u.ID)
+	if err != nil {
+		if models.IsErrTwoFactorNotEnrolled(err) {
+			handleSignIn(ctx, u, form.Remember)
+		} else {
+			ctx.ServerError("UserSignIn", err)
+		}
+		return
+	}
+
+	// User needs to use 2FA, save data and redirect to 2FA page.
+	if err := ctx.Session.Set("twofaUid", u.ID); err != nil {
+		ctx.ServerError("UserSignIn: Unable to set twofaUid in session", err)
+		return
+	}
+	if err := ctx.Session.Set("twofaRemember", form.Remember); err != nil {
+		ctx.ServerError("UserSignIn: Unable to set twofaRemember in session", err)
+		return
+	}
+	if err := ctx.Session.Release(); err != nil {
+		ctx.ServerError("UserSignIn: Unable to save session", err)
+		return
+	}
+
+	regs, err := models.GetU2FRegistrationsByUID(u.ID)
+	if err == nil && len(regs) > 0 {
+		ctx.Redirect(setting.AppSubURL + "/user/u2f")
+		return
+	}
+
+	ctx.Redirect(setting.AppSubURL + "/user/two_factor")
+}
+
+// TwoFactor shows the user a two-factor authentication page.
+func TwoFactor(ctx *context.Context) {
+	ctx.Data["Title"] = ctx.Tr("twofa")
+
+	// Check auto-login.
+	if checkAutoLogin(ctx) {
+		return
+	}
+
+	// Ensure user is in a 2FA session.
+	if ctx.Session.Get("twofaUid") == nil {
+		ctx.ServerError("UserSignIn", errors.New("not in 2FA session"))
+		return
+	}
+
+	ctx.HTML(http.StatusOK, tplTwofa)
+}
+
+// TwoFactorPost validates a user's two-factor authentication token.
+func TwoFactorPost(ctx *context.Context) {
+	form := web.GetForm(ctx).(*forms.TwoFactorAuthForm)
+	ctx.Data["Title"] = ctx.Tr("twofa")
+
+	// Ensure user is in a 2FA session.
+	idSess := ctx.Session.Get("twofaUid")
+	if idSess == nil {
+		ctx.ServerError("UserSignIn", errors.New("not in 2FA session"))
+		return
+	}
+
+	id := idSess.(int64)
+	twofa, err := models.GetTwoFactorByUID(id)
+	if err != nil {
+		ctx.ServerError("UserSignIn", err)
+		return
+	}
+
+	// Validate the passcode with the stored TOTP secret.
+	ok, err := twofa.ValidateTOTP(form.Passcode)
+	if err != nil {
+		ctx.ServerError("UserSignIn", err)
+		return
+	}
+
+	if ok && twofa.LastUsedPasscode != form.Passcode {
+		remember := ctx.Session.Get("twofaRemember").(bool)
+		u, err := models.GetUserByID(id)
+		if err != nil {
+			ctx.ServerError("UserSignIn", err)
+			return
+		}
+
+		if ctx.Session.Get("linkAccount") != nil {
+			gothUser := ctx.Session.Get("linkAccountGothUser")
+			if gothUser == nil {
+				ctx.ServerError("UserSignIn", errors.New("not in LinkAccount session"))
+				return
+			}
+
+			err = externalaccount.LinkAccountToUser(u, gothUser.(goth.User))
+			if err != nil {
+				ctx.ServerError("UserSignIn", err)
+				return
+			}
+		}
+
+		twofa.LastUsedPasscode = form.Passcode
+		if err = models.UpdateTwoFactor(twofa); err != nil {
+			ctx.ServerError("UserSignIn", err)
+			return
+		}
+
+		handleSignIn(ctx, u, remember)
+		return
+	}
+
+	ctx.RenderWithErr(ctx.Tr("auth.twofa_passcode_incorrect"), tplTwofa, forms.TwoFactorAuthForm{})
+}
+
+// TwoFactorScratch shows the scratch code form for two-factor authentication.
+func TwoFactorScratch(ctx *context.Context) {
+	ctx.Data["Title"] = ctx.Tr("twofa_scratch")
+
+	// Check auto-login.
+	if checkAutoLogin(ctx) {
+		return
+	}
+
+	// Ensure user is in a 2FA session.
+	if ctx.Session.Get("twofaUid") == nil {
+		ctx.ServerError("UserSignIn", errors.New("not in 2FA session"))
+		return
+	}
+
+	ctx.HTML(http.StatusOK, tplTwofaScratch)
+}
+
+// TwoFactorScratchPost validates and invalidates a user's two-factor scratch token.
+func TwoFactorScratchPost(ctx *context.Context) {
+	form := web.GetForm(ctx).(*forms.TwoFactorScratchAuthForm)
+	ctx.Data["Title"] = ctx.Tr("twofa_scratch")
+
+	// Ensure user is in a 2FA session.
+	idSess := ctx.Session.Get("twofaUid")
+	if idSess == nil {
+		ctx.ServerError("UserSignIn", errors.New("not in 2FA session"))
+		return
+	}
+
+	id := idSess.(int64)
+	twofa, err := models.GetTwoFactorByUID(id)
+	if err != nil {
+		ctx.ServerError("UserSignIn", err)
+		return
+	}
+
+	// Validate the passcode with the stored TOTP secret.
+	if twofa.VerifyScratchToken(form.Token) {
+		// Invalidate the scratch token.
+		_, err = twofa.GenerateScratchToken()
+		if err != nil {
+			ctx.ServerError("UserSignIn", err)
+			return
+		}
+		if err = models.UpdateTwoFactor(twofa); err != nil {
+			ctx.ServerError("UserSignIn", err)
+			return
+		}
+
+		remember := ctx.Session.Get("twofaRemember").(bool)
+		u, err := models.GetUserByID(id)
+		if err != nil {
+			ctx.ServerError("UserSignIn", err)
+			return
+		}
+
+		handleSignInFull(ctx, u, remember, false)
+		ctx.Flash.Info(ctx.Tr("auth.twofa_scratch_used"))
+		ctx.Redirect(setting.AppSubURL + "/user/settings/security")
+		return
+	}
+
+	ctx.RenderWithErr(ctx.Tr("auth.twofa_scratch_token_incorrect"), tplTwofaScratch, forms.TwoFactorScratchAuthForm{})
+}
+
+// U2F shows the U2F login page
+func U2F(ctx *context.Context) {
+	ctx.Data["Title"] = ctx.Tr("twofa")
+	ctx.Data["RequireU2F"] = true
+	// Check auto-login.
+	if checkAutoLogin(ctx) {
+		return
+	}
+
+	// Ensure user is in a 2FA session.
+	if ctx.Session.Get("twofaUid") == nil {
+		ctx.ServerError("UserSignIn", errors.New("not in U2F session"))
+		return
+	}
+
+	ctx.HTML(http.StatusOK, tplU2F)
+}
+
+// U2FChallenge submits a sign challenge to the browser
+func U2FChallenge(ctx *context.Context) {
+	// Ensure user is in a U2F session.
+	idSess := ctx.Session.Get("twofaUid")
+	if idSess == nil {
+		ctx.ServerError("UserSignIn", errors.New("not in U2F session"))
+		return
+	}
+	id := idSess.(int64)
+	regs, err := models.GetU2FRegistrationsByUID(id)
+	if err != nil {
+		ctx.ServerError("UserSignIn", err)
+		return
+	}
+	if len(regs) == 0 {
+		ctx.ServerError("UserSignIn", errors.New("no device registered"))
+		return
+	}
+	challenge, err := u2f.NewChallenge(setting.U2F.AppID, setting.U2F.TrustedFacets)
+	if err != nil {
+		ctx.ServerError("u2f.NewChallenge", err)
+		return
+	}
+	if err := ctx.Session.Set("u2fChallenge", challenge); err != nil {
+		ctx.ServerError("UserSignIn: unable to set u2fChallenge in session", err)
+		return
+	}
+	if err := ctx.Session.Release(); err != nil {
+		ctx.ServerError("UserSignIn: unable to store session", err)
+	}
+
+	ctx.JSON(http.StatusOK, challenge.SignRequest(regs.ToRegistrations()))
+}
+
+// U2FSign authenticates the user by signResp
+func U2FSign(ctx *context.Context) {
+	signResp := web.GetForm(ctx).(*u2f.SignResponse)
+	challSess := ctx.Session.Get("u2fChallenge")
+	idSess := ctx.Session.Get("twofaUid")
+	if challSess == nil || idSess == nil {
+		ctx.ServerError("UserSignIn", errors.New("not in U2F session"))
+		return
+	}
+	challenge := challSess.(*u2f.Challenge)
+	id := idSess.(int64)
+	regs, err := models.GetU2FRegistrationsByUID(id)
+	if err != nil {
+		ctx.ServerError("UserSignIn", err)
+		return
+	}
+	for _, reg := range regs {
+		r, err := reg.Parse()
+		if err != nil {
+			log.Fatal("parsing u2f registration: %v", err)
+			continue
+		}
+		newCounter, authErr := r.Authenticate(*signResp, *challenge, reg.Counter)
+		if authErr == nil {
+			reg.Counter = newCounter
+			user, err := models.GetUserByID(id)
+			if err != nil {
+				ctx.ServerError("UserSignIn", err)
+				return
+			}
+			remember := ctx.Session.Get("twofaRemember").(bool)
+			if err := reg.UpdateCounter(); err != nil {
+				ctx.ServerError("UserSignIn", err)
+				return
+			}
+
+			if ctx.Session.Get("linkAccount") != nil {
+				gothUser := ctx.Session.Get("linkAccountGothUser")
+				if gothUser == nil {
+					ctx.ServerError("UserSignIn", errors.New("not in LinkAccount session"))
+					return
+				}
+
+				err = externalaccount.LinkAccountToUser(user, gothUser.(goth.User))
+				if err != nil {
+					ctx.ServerError("UserSignIn", err)
+					return
+				}
+			}
+			redirect := handleSignInFull(ctx, user, remember, false)
+			if redirect == "" {
+				redirect = setting.AppSubURL + "/"
+			}
+			ctx.PlainText(200, []byte(redirect))
+			return
+		}
+	}
+	ctx.Error(http.StatusUnauthorized)
+}
+
+// This handles the final part of the sign-in process of the user.
+func handleSignIn(ctx *context.Context, u *models.User, remember bool) {
+	handleSignInFull(ctx, u, remember, true)
+}
+
+func handleSignInFull(ctx *context.Context, u *models.User, remember bool, obeyRedirect bool) string {
+	if remember {
+		days := 86400 * setting.LogInRememberDays
+		ctx.SetCookie(setting.CookieUserName, u.Name, days)
+		ctx.SetSuperSecureCookie(base.EncodeMD5(u.Rands+u.Passwd),
+			setting.CookieRememberName, u.Name, days)
+	}
+
+	_ = ctx.Session.Delete("openid_verified_uri")
+	_ = ctx.Session.Delete("openid_signin_remember")
+	_ = ctx.Session.Delete("openid_determined_email")
+	_ = ctx.Session.Delete("openid_determined_username")
+	_ = ctx.Session.Delete("twofaUid")
+	_ = ctx.Session.Delete("twofaRemember")
+	_ = ctx.Session.Delete("u2fChallenge")
+	_ = ctx.Session.Delete("linkAccount")
+	if err := ctx.Session.Set("uid", u.ID); err != nil {
+		log.Error("Error setting uid %d in session: %v", u.ID, err)
+	}
+	if err := ctx.Session.Set("uname", u.Name); err != nil {
+		log.Error("Error setting uname %s session: %v", u.Name, err)
+	}
+	if err := ctx.Session.Release(); err != nil {
+		log.Error("Unable to store session: %v", err)
+	}
+
+	// Language setting of the user overwrites the one previously set
+	// If the user does not have a locale set, we save the current one.
+	if len(u.Language) == 0 {
+		u.Language = ctx.Locale.Language()
+		if err := models.UpdateUserCols(u, "language"); err != nil {
+			log.Error(fmt.Sprintf("Error updating user language [user: %d, locale: %s]", u.ID, u.Language))
+			return setting.AppSubURL + "/"
+		}
+	}
+
+	middleware.SetLocaleCookie(ctx.Resp, u.Language, 0)
+
+	// Clear whatever CSRF has right now, force to generate a new one
+	middleware.DeleteCSRFCookie(ctx.Resp)
+
+	// Register last login
+	u.SetLastLogin()
+	if err := models.UpdateUserCols(u, "last_login_unix"); err != nil {
+		ctx.ServerError("UpdateUserCols", err)
+		return setting.AppSubURL + "/"
+	}
+
+	if redirectTo := ctx.GetCookie("redirect_to"); len(redirectTo) > 0 && !utils.IsExternalURL(redirectTo) {
+		middleware.DeleteRedirectToCookie(ctx.Resp)
+		if obeyRedirect {
+			ctx.RedirectToFirst(redirectTo)
+		}
+		return redirectTo
+	}
+
+	if obeyRedirect {
+		ctx.Redirect(setting.AppSubURL + "/")
+	}
+	return setting.AppSubURL + "/"
+}
+
+// SignInOAuth handles the OAuth2 login buttons
+func SignInOAuth(ctx *context.Context) {
+	provider := ctx.Params(":provider")
+
+	loginSource, err := models.GetActiveOAuth2LoginSourceByName(provider)
+	if err != nil {
+		ctx.ServerError("SignIn", err)
+		return
+	}
+
+	// try to do a direct callback flow, so we don't authenticate the user again but use the valid accesstoken to get the user
+	user, gothUser, err := oAuth2UserLoginCallback(loginSource, ctx.Req, ctx.Resp)
+	if err == nil && user != nil {
+		// we got the user without going through the whole OAuth2 authentication flow again
+		handleOAuth2SignIn(ctx, user, gothUser)
+		return
+	}
+
+	if err = oauth2.Auth(loginSource.Name, ctx.Req, ctx.Resp); err != nil {
+		if strings.Contains(err.Error(), "no provider for ") {
+			if err = models.ResetOAuth2(); err != nil {
+				ctx.ServerError("SignIn", err)
+				return
+			}
+			if err = oauth2.Auth(loginSource.Name, ctx.Req, ctx.Resp); err != nil {
+				ctx.ServerError("SignIn", err)
+			}
+			return
+		}
+		ctx.ServerError("SignIn", err)
+	}
+	// redirect is done in oauth2.Auth
+}
+
+// SignInOAuthCallback handles the callback from the given provider
+func SignInOAuthCallback(ctx *context.Context) {
+	provider := ctx.Params(":provider")
+
+	// first look if the provider is still active
+	loginSource, err := models.GetActiveOAuth2LoginSourceByName(provider)
+	if err != nil {
+		ctx.ServerError("SignIn", err)
+		return
+	}
+
+	if loginSource == nil {
+		ctx.ServerError("SignIn", errors.New("No valid provider found, check configured callback url in provider"))
+		return
+	}
+
+	u, gothUser, err := oAuth2UserLoginCallback(loginSource, ctx.Req, ctx.Resp)
+
+	if err != nil {
+		ctx.ServerError("UserSignIn", err)
+		return
+	}
+
+	if u == nil {
+		if !(setting.Service.DisableRegistration || setting.Service.AllowOnlyInternalRegistration) && setting.OAuth2Client.EnableAutoRegistration {
+			// create new user with details from oauth2 provider
+			var missingFields []string
+			if gothUser.UserID == "" {
+				missingFields = append(missingFields, "sub")
+			}
+			if gothUser.Email == "" {
+				missingFields = append(missingFields, "email")
+			}
+			if setting.OAuth2Client.Username == setting.OAuth2UsernameNickname && gothUser.NickName == "" {
+				missingFields = append(missingFields, "nickname")
+			}
+			if len(missingFields) > 0 {
+				log.Error("OAuth2 Provider %s returned empty or missing fields: %s", loginSource.Name, missingFields)
+				if loginSource.IsOAuth2() && loginSource.OAuth2().Provider == "openidConnect" {
+					log.Error("You may need to change the 'OPENID_CONNECT_SCOPES' setting to request all required fields")
+				}
+				err = fmt.Errorf("OAuth2 Provider %s returned empty or missing fields: %s", loginSource.Name, missingFields)
+				ctx.ServerError("CreateUser", err)
+				return
+			}
+			u = &models.User{
+				Name:        getUserName(&gothUser),
+				FullName:    gothUser.Name,
+				Email:       gothUser.Email,
+				IsActive:    !setting.OAuth2Client.RegisterEmailConfirm,
+				LoginType:   models.LoginOAuth2,
+				LoginSource: loginSource.ID,
+				LoginName:   gothUser.UserID,
+			}
+
+			if !createAndHandleCreatedUser(ctx, base.TplName(""), nil, u, &gothUser, setting.OAuth2Client.AccountLinking != setting.OAuth2AccountLinkingDisabled) {
+				// error already handled
+				return
+			}
+		} else {
+			// no existing user is found, request attach or new account
+			showLinkingLogin(ctx, gothUser)
+			return
+		}
+	}
+
+	handleOAuth2SignIn(ctx, u, gothUser)
+}
+
+func getUserName(gothUser *goth.User) string {
+	switch setting.OAuth2Client.Username {
+	case setting.OAuth2UsernameEmail:
+		return strings.Split(gothUser.Email, "@")[0]
+	case setting.OAuth2UsernameNickname:
+		return gothUser.NickName
+	default: // OAuth2UsernameUserid
+		return gothUser.UserID
+	}
+}
+
+func showLinkingLogin(ctx *context.Context, gothUser goth.User) {
+	if err := ctx.Session.Set("linkAccountGothUser", gothUser); err != nil {
+		log.Error("Error setting linkAccountGothUser in session: %v", err)
+	}
+	if err := ctx.Session.Release(); err != nil {
+		log.Error("Error storing session: %v", err)
+	}
+	ctx.Redirect(setting.AppSubURL + "/user/link_account")
+}
+
+func updateAvatarIfNeed(url string, u *models.User) {
+	if setting.OAuth2Client.UpdateAvatar && len(url) > 0 {
+		resp, err := http.Get(url)
+		if err == nil {
+			defer func() {
+				_ = resp.Body.Close()
+			}()
+		}
+		// ignore any error
+		if err == nil && resp.StatusCode == http.StatusOK {
+			data, err := ioutil.ReadAll(io.LimitReader(resp.Body, setting.Avatar.MaxFileSize+1))
+			if err == nil && int64(len(data)) <= setting.Avatar.MaxFileSize {
+				_ = u.UploadAvatar(data)
+			}
+		}
+	}
+}
+
+func handleOAuth2SignIn(ctx *context.Context, u *models.User, gothUser goth.User) {
+	updateAvatarIfNeed(gothUser.AvatarURL, u)
+
+	// If this user is enrolled in 2FA, we can't sign the user in just yet.
+	// Instead, redirect them to the 2FA authentication page.
+	_, err := models.GetTwoFactorByUID(u.ID)
+	if err != nil {
+		if !models.IsErrTwoFactorNotEnrolled(err) {
+			ctx.ServerError("UserSignIn", err)
+			return
+		}
+
+		if err := ctx.Session.Set("uid", u.ID); err != nil {
+			log.Error("Error setting uid in session: %v", err)
+		}
+		if err := ctx.Session.Set("uname", u.Name); err != nil {
+			log.Error("Error setting uname in session: %v", err)
+		}
+		if err := ctx.Session.Release(); err != nil {
+			log.Error("Error storing session: %v", err)
+		}
+
+		// Clear whatever CSRF has right now, force to generate a new one
+		middleware.DeleteCSRFCookie(ctx.Resp)
+
+		// Register last login
+		u.SetLastLogin()
+		if err := models.UpdateUserCols(u, "last_login_unix"); err != nil {
+			ctx.ServerError("UpdateUserCols", err)
+			return
+		}
+
+		// update external user information
+		if err := models.UpdateExternalUser(u, gothUser); err != nil {
+			log.Error("UpdateExternalUser failed: %v", err)
+		}
+
+		if redirectTo := ctx.GetCookie("redirect_to"); len(redirectTo) > 0 {
+			middleware.DeleteRedirectToCookie(ctx.Resp)
+			ctx.RedirectToFirst(redirectTo)
+			return
+		}
+
+		ctx.Redirect(setting.AppSubURL + "/")
+		return
+	}
+
+	// User needs to use 2FA, save data and redirect to 2FA page.
+	if err := ctx.Session.Set("twofaUid", u.ID); err != nil {
+		log.Error("Error setting twofaUid in session: %v", err)
+	}
+	if err := ctx.Session.Set("twofaRemember", false); err != nil {
+		log.Error("Error setting twofaRemember in session: %v", err)
+	}
+	if err := ctx.Session.Release(); err != nil {
+		log.Error("Error storing session: %v", err)
+	}
+
+	// If U2F is enrolled -> Redirect to U2F instead
+	regs, err := models.GetU2FRegistrationsByUID(u.ID)
+	if err == nil && len(regs) > 0 {
+		ctx.Redirect(setting.AppSubURL + "/user/u2f")
+		return
+	}
+
+	ctx.Redirect(setting.AppSubURL + "/user/two_factor")
+}
+
+// OAuth2UserLoginCallback attempts to handle the callback from the OAuth2 provider and if successful
+// login the user
+func oAuth2UserLoginCallback(loginSource *models.LoginSource, request *http.Request, response http.ResponseWriter) (*models.User, goth.User, error) {
+	gothUser, err := oauth2.ProviderCallback(loginSource.Name, request, response)
+
+	if err != nil {
+		if err.Error() == "securecookie: the value is too long" {
+			log.Error("OAuth2 Provider %s returned too long a token. Current max: %d. Either increase the [OAuth2] MAX_TOKEN_LENGTH or reduce the information returned from the OAuth2 provider", loginSource.Name, setting.OAuth2.MaxTokenLength)
+			err = fmt.Errorf("OAuth2 Provider %s returned too long a token. Current max: %d. Either increase the [OAuth2] MAX_TOKEN_LENGTH or reduce the information returned from the OAuth2 provider", loginSource.Name, setting.OAuth2.MaxTokenLength)
+		}
+		return nil, goth.User{}, err
+	}
+
+	user := &models.User{
+		LoginName:   gothUser.UserID,
+		LoginType:   models.LoginOAuth2,
+		LoginSource: loginSource.ID,
+	}
+
+	hasUser, err := models.GetUser(user)
+	if err != nil {
+		return nil, goth.User{}, err
+	}
+
+	if hasUser {
+		return user, gothUser, nil
+	}
+
+	// search in external linked users
+	externalLoginUser := &models.ExternalLoginUser{
+		ExternalID:    gothUser.UserID,
+		LoginSourceID: loginSource.ID,
+	}
+	hasUser, err = models.GetExternalLogin(externalLoginUser)
+	if err != nil {
+		return nil, goth.User{}, err
+	}
+	if hasUser {
+		user, err = models.GetUserByID(externalLoginUser.UserID)
+		return user, gothUser, err
+	}
+
+	// no user found to login
+	return nil, gothUser, nil
+
+}
+
+// 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.RequireExternalRegistrationPassword || setting.Service.AllowOnlyExternalRegistration
+	ctx.Data["Title"] = ctx.Tr("link_account")
+	ctx.Data["LinkAccountMode"] = true
+	ctx.Data["EnableCaptcha"] = setting.Service.EnableCaptcha && setting.Service.RequireExternalRegistrationCaptcha
+	ctx.Data["Captcha"] = context.GetImageCaptcha()
+	ctx.Data["CaptchaType"] = setting.Service.CaptchaType
+	ctx.Data["RecaptchaURL"] = setting.Service.RecaptchaURL
+	ctx.Data["RecaptchaSitekey"] = setting.Service.RecaptchaSitekey
+	ctx.Data["HcaptchaSitekey"] = setting.Service.HcaptchaSitekey
+	ctx.Data["DisableRegistration"] = setting.Service.DisableRegistration
+	ctx.Data["AllowOnlyInternalRegistration"] = setting.Service.AllowOnlyInternalRegistration
+	ctx.Data["ShowRegistrationButton"] = false
+
+	// use this to set the right link into the signIn and signUp templates in the link_account template
+	ctx.Data["SignInLink"] = setting.AppSubURL + "/user/link_account_signin"
+	ctx.Data["SignUpLink"] = setting.AppSubURL + "/user/link_account_signup"
+
+	gothUser := ctx.Session.Get("linkAccountGothUser")
+	if gothUser == nil {
+		ctx.ServerError("UserSignIn", errors.New("not in LinkAccount session"))
+		return
+	}
+
+	gu, _ := gothUser.(goth.User)
+	uname := getUserName(&gu)
+	email := gu.Email
+	ctx.Data["user_name"] = uname
+	ctx.Data["email"] = email
+
+	if len(email) != 0 {
+		u, err := models.GetUserByEmail(email)
+		if err != nil && !models.IsErrUserNotExist(err) {
+			ctx.ServerError("UserSignIn", err)
+			return
+		}
+		if u != nil {
+			ctx.Data["user_exists"] = true
+		}
+	} else if len(uname) != 0 {
+		u, err := models.GetUserByName(uname)
+		if err != nil && !models.IsErrUserNotExist(err) {
+			ctx.ServerError("UserSignIn", err)
+			return
+		}
+		if u != nil {
+			ctx.Data["user_exists"] = true
+		}
+	}
+
+	ctx.HTML(http.StatusOK, tplLinkAccount)
+}
+
+// LinkAccountPostSignIn handle the coupling of external account with another account using signIn
+func LinkAccountPostSignIn(ctx *context.Context) {
+	signInForm := web.GetForm(ctx).(*forms.SignInForm)
+	ctx.Data["DisablePassword"] = !setting.Service.RequireExternalRegistrationPassword || setting.Service.AllowOnlyExternalRegistration
+	ctx.Data["Title"] = ctx.Tr("link_account")
+	ctx.Data["LinkAccountMode"] = true
+	ctx.Data["LinkAccountModeSignIn"] = true
+	ctx.Data["EnableCaptcha"] = setting.Service.EnableCaptcha && setting.Service.RequireExternalRegistrationCaptcha
+	ctx.Data["RecaptchaURL"] = setting.Service.RecaptchaURL
+	ctx.Data["Captcha"] = context.GetImageCaptcha()
+	ctx.Data["CaptchaType"] = setting.Service.CaptchaType
+	ctx.Data["RecaptchaSitekey"] = setting.Service.RecaptchaSitekey
+	ctx.Data["HcaptchaSitekey"] = setting.Service.HcaptchaSitekey
+	ctx.Data["DisableRegistration"] = setting.Service.DisableRegistration
+	ctx.Data["ShowRegistrationButton"] = false
+
+	// use this to set the right link into the signIn and signUp templates in the link_account template
+	ctx.Data["SignInLink"] = setting.AppSubURL + "/user/link_account_signin"
+	ctx.Data["SignUpLink"] = setting.AppSubURL + "/user/link_account_signup"
+
+	gothUser := ctx.Session.Get("linkAccountGothUser")
+	if gothUser == nil {
+		ctx.ServerError("UserSignIn", errors.New("not in LinkAccount session"))
+		return
+	}
+
+	if ctx.HasError() {
+		ctx.HTML(http.StatusOK, tplLinkAccount)
+		return
+	}
+
+	u, err := models.UserSignIn(signInForm.UserName, signInForm.Password)
+	if err != nil {
+		if models.IsErrUserNotExist(err) {
+			ctx.Data["user_exists"] = true
+			ctx.RenderWithErr(ctx.Tr("form.username_password_incorrect"), tplLinkAccount, &signInForm)
+		} else {
+			ctx.ServerError("UserLinkAccount", err)
+		}
+		return
+	}
+
+	linkAccount(ctx, u, gothUser.(goth.User), signInForm.Remember)
+}
+
+func linkAccount(ctx *context.Context, u *models.User, gothUser goth.User, remember bool) {
+	updateAvatarIfNeed(gothUser.AvatarURL, u)
+
+	// If this user is enrolled in 2FA, we can't sign the user in just yet.
+	// Instead, redirect them to the 2FA authentication page.
+	_, err := models.GetTwoFactorByUID(u.ID)
+	if err != nil {
+		if !models.IsErrTwoFactorNotEnrolled(err) {
+			ctx.ServerError("UserLinkAccount", err)
+			return
+		}
+
+		err = externalaccount.LinkAccountToUser(u, gothUser)
+		if err != nil {
+			ctx.ServerError("UserLinkAccount", err)
+			return
+		}
+
+		handleSignIn(ctx, u, remember)
+		return
+	}
+
+	// User needs to use 2FA, save data and redirect to 2FA page.
+	if err := ctx.Session.Set("twofaUid", u.ID); err != nil {
+		log.Error("Error setting twofaUid in session: %v", err)
+	}
+	if err := ctx.Session.Set("twofaRemember", remember); err != nil {
+		log.Error("Error setting twofaRemember in session: %v", err)
+	}
+	if err := ctx.Session.Set("linkAccount", true); err != nil {
+		log.Error("Error setting linkAccount in session: %v", err)
+	}
+	if err := ctx.Session.Release(); err != nil {
+		log.Error("Error storing session: %v", err)
+	}
+
+	// If U2F is enrolled -> Redirect to U2F instead
+	regs, err := models.GetU2FRegistrationsByUID(u.ID)
+	if err == nil && len(regs) > 0 {
+		ctx.Redirect(setting.AppSubURL + "/user/u2f")
+		return
+	}
+
+	ctx.Redirect(setting.AppSubURL + "/user/two_factor")
+}
+
+// LinkAccountPostRegister handle the creation of a new account for an external account using signUp
+func LinkAccountPostRegister(ctx *context.Context) {
+	form := web.GetForm(ctx).(*forms.RegisterForm)
+	// TODO Make insecure passwords optional for local accounts also,
+	//      once email-based Second-Factor Auth is available
+	ctx.Data["DisablePassword"] = !setting.Service.RequireExternalRegistrationPassword || setting.Service.AllowOnlyExternalRegistration
+	ctx.Data["Title"] = ctx.Tr("link_account")
+	ctx.Data["LinkAccountMode"] = true
+	ctx.Data["LinkAccountModeRegister"] = true
+	ctx.Data["EnableCaptcha"] = setting.Service.EnableCaptcha && setting.Service.RequireExternalRegistrationCaptcha
+	ctx.Data["RecaptchaURL"] = setting.Service.RecaptchaURL
+	ctx.Data["Captcha"] = context.GetImageCaptcha()
+	ctx.Data["CaptchaType"] = setting.Service.CaptchaType
+	ctx.Data["RecaptchaSitekey"] = setting.Service.RecaptchaSitekey
+	ctx.Data["HcaptchaSitekey"] = setting.Service.HcaptchaSitekey
+	ctx.Data["DisableRegistration"] = setting.Service.DisableRegistration
+	ctx.Data["ShowRegistrationButton"] = false
+
+	// use this to set the right link into the signIn and signUp templates in the link_account template
+	ctx.Data["SignInLink"] = setting.AppSubURL + "/user/link_account_signin"
+	ctx.Data["SignUpLink"] = setting.AppSubURL + "/user/link_account_signup"
+
+	gothUserInterface := ctx.Session.Get("linkAccountGothUser")
+	if gothUserInterface == nil {
+		ctx.ServerError("UserSignUp", errors.New("not in LinkAccount session"))
+		return
+	}
+	gothUser, ok := gothUserInterface.(goth.User)
+	if !ok {
+		ctx.ServerError("UserSignUp", fmt.Errorf("session linkAccountGothUser type is %t but not goth.User", gothUserInterface))
+		return
+	}
+
+	if ctx.HasError() {
+		ctx.HTML(http.StatusOK, tplLinkAccount)
+		return
+	}
+
+	if setting.Service.DisableRegistration || setting.Service.AllowOnlyInternalRegistration {
+		ctx.Error(http.StatusForbidden)
+		return
+	}
+
+	if setting.Service.EnableCaptcha && setting.Service.RequireExternalRegistrationCaptcha {
+		var valid bool
+		var err error
+		switch setting.Service.CaptchaType {
+		case setting.ImageCaptcha:
+			valid = context.GetImageCaptcha().VerifyReq(ctx.Req)
+		case setting.ReCaptcha:
+			valid, err = recaptcha.Verify(ctx, form.GRecaptchaResponse)
+		case setting.HCaptcha:
+			valid, err = hcaptcha.Verify(ctx, form.HcaptchaResponse)
+		default:
+			ctx.ServerError("Unknown Captcha Type", fmt.Errorf("Unknown Captcha Type: %s", setting.Service.CaptchaType))
+			return
+		}
+		if err != nil {
+			log.Debug("%s", err.Error())
+		}
+
+		if !valid {
+			ctx.Data["Err_Captcha"] = true
+			ctx.RenderWithErr(ctx.Tr("form.captcha_incorrect"), tplLinkAccount, &form)
+			return
+		}
+	}
+
+	if !form.IsEmailDomainAllowed() {
+		ctx.RenderWithErr(ctx.Tr("auth.email_domain_blacklisted"), 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.Provider)
+	if err != nil {
+		ctx.ServerError("CreateUser", err)
+	}
+
+	u := &models.User{
+		Name:        form.UserName,
+		Email:       form.Email,
+		Passwd:      form.Password,
+		IsActive:    !(setting.Service.RegisterEmailConfirm || setting.Service.RegisterManualConfirm),
+		LoginType:   models.LoginOAuth2,
+		LoginSource: loginSource.ID,
+		LoginName:   gothUser.UserID,
+	}
+
+	if !createAndHandleCreatedUser(ctx, tplLinkAccount, form, u, &gothUser, false) {
+		// error already handled
+		return
+	}
+
+	ctx.Redirect(setting.AppSubURL + "/user/login")
+}
+
+// HandleSignOut resets the session and sets the cookies
+func HandleSignOut(ctx *context.Context) {
+	_ = ctx.Session.Flush()
+	_ = ctx.Session.Destroy(ctx.Resp, ctx.Req)
+	ctx.DeleteCookie(setting.CookieUserName)
+	ctx.DeleteCookie(setting.CookieRememberName)
+	middleware.DeleteCSRFCookie(ctx.Resp)
+	middleware.DeleteLocaleCookie(ctx.Resp)
+	middleware.DeleteRedirectToCookie(ctx.Resp)
+}
+
+// SignOut sign out from login status
+func SignOut(ctx *context.Context) {
+	if ctx.User != nil {
+		eventsource.GetManager().SendMessageBlocking(ctx.User.ID, &eventsource.Event{
+			Name: "logout",
+			Data: ctx.Session.ID(),
+		})
+	}
+	HandleSignOut(ctx)
+	ctx.Redirect(setting.AppSubURL + "/")
+}
+
+// SignUp render the register page
+func SignUp(ctx *context.Context) {
+	ctx.Data["Title"] = ctx.Tr("sign_up")
+
+	ctx.Data["SignUpLink"] = setting.AppSubURL + "/user/sign_up"
+
+	ctx.Data["EnableCaptcha"] = setting.Service.EnableCaptcha
+	ctx.Data["RecaptchaURL"] = setting.Service.RecaptchaURL
+	ctx.Data["Captcha"] = context.GetImageCaptcha()
+	ctx.Data["CaptchaType"] = setting.Service.CaptchaType
+	ctx.Data["RecaptchaSitekey"] = setting.Service.RecaptchaSitekey
+	ctx.Data["HcaptchaSitekey"] = setting.Service.HcaptchaSitekey
+	ctx.Data["PageIsSignUp"] = true
+
+	//Show Disabled Registration message if DisableRegistration or AllowOnlyExternalRegistration options are true
+	ctx.Data["DisableRegistration"] = setting.Service.DisableRegistration || setting.Service.AllowOnlyExternalRegistration
+
+	ctx.HTML(http.StatusOK, tplSignUp)
+}
+
+// SignUpPost response for sign up information submission
+func SignUpPost(ctx *context.Context) {
+	form := web.GetForm(ctx).(*forms.RegisterForm)
+	ctx.Data["Title"] = ctx.Tr("sign_up")
+
+	ctx.Data["SignUpLink"] = setting.AppSubURL + "/user/sign_up"
+
+	ctx.Data["EnableCaptcha"] = setting.Service.EnableCaptcha
+	ctx.Data["RecaptchaURL"] = setting.Service.RecaptchaURL
+	ctx.Data["Captcha"] = context.GetImageCaptcha()
+	ctx.Data["CaptchaType"] = setting.Service.CaptchaType
+	ctx.Data["RecaptchaSitekey"] = setting.Service.RecaptchaSitekey
+	ctx.Data["HcaptchaSitekey"] = setting.Service.HcaptchaSitekey
+	ctx.Data["PageIsSignUp"] = true
+
+	//Permission denied if DisableRegistration or AllowOnlyExternalRegistration options are true
+	if setting.Service.DisableRegistration || setting.Service.AllowOnlyExternalRegistration {
+		ctx.Error(http.StatusForbidden)
+		return
+	}
+
+	if ctx.HasError() {
+		ctx.HTML(http.StatusOK, tplSignUp)
+		return
+	}
+
+	if setting.Service.EnableCaptcha {
+		var valid bool
+		var err error
+		switch setting.Service.CaptchaType {
+		case setting.ImageCaptcha:
+			valid = context.GetImageCaptcha().VerifyReq(ctx.Req)
+		case setting.ReCaptcha:
+			valid, err = recaptcha.Verify(ctx, form.GRecaptchaResponse)
+		case setting.HCaptcha:
+			valid, err = hcaptcha.Verify(ctx, form.HcaptchaResponse)
+		default:
+			ctx.ServerError("Unknown Captcha Type", fmt.Errorf("Unknown Captcha Type: %s", setting.Service.CaptchaType))
+			return
+		}
+		if err != nil {
+			log.Debug("%s", err.Error())
+		}
+
+		if !valid {
+			ctx.Data["Err_Captcha"] = true
+			ctx.RenderWithErr(ctx.Tr("form.captcha_incorrect"), tplSignUp, &form)
+			return
+		}
+	}
+
+	if !form.IsEmailDomainAllowed() {
+		ctx.RenderWithErr(ctx.Tr("auth.email_domain_blacklisted"), tplSignUp, &form)
+		return
+	}
+
+	if form.Password != form.Retype {
+		ctx.Data["Err_Password"] = true
+		ctx.RenderWithErr(ctx.Tr("form.password_not_match"), tplSignUp, &form)
+		return
+	}
+	if len(form.Password) < setting.MinPasswordLength {
+		ctx.Data["Err_Password"] = true
+		ctx.RenderWithErr(ctx.Tr("auth.password_too_short", setting.MinPasswordLength), tplSignUp, &form)
+		return
+	}
+	if !password.IsComplexEnough(form.Password) {
+		ctx.Data["Err_Password"] = true
+		ctx.RenderWithErr(password.BuildComplexityError(ctx), tplSignUp, &form)
+		return
+	}
+	pwned, err := password.IsPwned(ctx, form.Password)
+	if pwned {
+		errMsg := ctx.Tr("auth.password_pwned")
+		if err != nil {
+			log.Error(err.Error())
+			errMsg = ctx.Tr("auth.password_pwned_err")
+		}
+		ctx.Data["Err_Password"] = true
+		ctx.RenderWithErr(errMsg, tplSignUp, &form)
+		return
+	}
+
+	u := &models.User{
+		Name:     form.UserName,
+		Email:    form.Email,
+		Passwd:   form.Password,
+		IsActive: !(setting.Service.RegisterEmailConfirm || setting.Service.RegisterManualConfirm),
+	}
+
+	if !createAndHandleCreatedUser(ctx, tplSignUp, form, u, nil, false) {
+		// error already handled
+		return
+	}
+
+	ctx.Flash.Success(ctx.Tr("auth.sign_up_successful"))
+	handleSignInFull(ctx, u, false, true)
+}
+
+// createAndHandleCreatedUser calls createUserInContext and
+// then handleUserCreated.
+func createAndHandleCreatedUser(ctx *context.Context, tpl base.TplName, form interface{}, u *models.User, gothUser *goth.User, allowLink bool) bool {
+	if !createUserInContext(ctx, tpl, form, u, gothUser, allowLink) {
+		return false
+	}
+	return handleUserCreated(ctx, u, gothUser)
+}
+
+// createUserInContext creates a user and handles errors within a given context.
+// Optionally a template can be specified.
+func createUserInContext(ctx *context.Context, tpl base.TplName, form interface{}, u *models.User, gothUser *goth.User, allowLink bool) (ok bool) {
+	if err := models.CreateUser(u); err != nil {
+		if allowLink && (models.IsErrUserAlreadyExist(err) || models.IsErrEmailAlreadyUsed(err)) {
+			if setting.OAuth2Client.AccountLinking == setting.OAuth2AccountLinkingAuto {
+				var user *models.User
+				user = &models.User{Name: u.Name}
+				hasUser, err := models.GetUser(user)
+				if !hasUser || err != nil {
+					user = &models.User{Email: u.Email}
+					hasUser, err = models.GetUser(user)
+					if !hasUser || err != nil {
+						ctx.ServerError("UserLinkAccount", err)
+						return
+					}
+				}
+
+				// TODO: probably we should respect 'remember' user's choice...
+				linkAccount(ctx, user, *gothUser, true)
+				return // user is already created here, all redirects are handled
+			} else if setting.OAuth2Client.AccountLinking == setting.OAuth2AccountLinkingLogin {
+				showLinkingLogin(ctx, *gothUser)
+				return // user will be created only after linking login
+			}
+		}
+
+		// handle error without template
+		if len(tpl) == 0 {
+			ctx.ServerError("CreateUser", err)
+			return
+		}
+
+		// handle error with template
+		switch {
+		case models.IsErrUserAlreadyExist(err):
+			ctx.Data["Err_UserName"] = true
+			ctx.RenderWithErr(ctx.Tr("form.username_been_taken"), tpl, form)
+		case models.IsErrEmailAlreadyUsed(err):
+			ctx.Data["Err_Email"] = true
+			ctx.RenderWithErr(ctx.Tr("form.email_been_used"), tpl, form)
+		case models.IsErrEmailInvalid(err):
+			ctx.Data["Err_Email"] = true
+			ctx.RenderWithErr(ctx.Tr("form.email_invalid"), tpl, form)
+		case models.IsErrNameReserved(err):
+			ctx.Data["Err_UserName"] = true
+			ctx.RenderWithErr(ctx.Tr("user.form.name_reserved", err.(models.ErrNameReserved).Name), tpl, form)
+		case models.IsErrNamePatternNotAllowed(err):
+			ctx.Data["Err_UserName"] = true
+			ctx.RenderWithErr(ctx.Tr("user.form.name_pattern_not_allowed", err.(models.ErrNamePatternNotAllowed).Pattern), tpl, form)
+		case models.IsErrNameCharsNotAllowed(err):
+			ctx.Data["Err_UserName"] = true
+			ctx.RenderWithErr(ctx.Tr("user.form.name_chars_not_allowed", err.(models.ErrNameCharsNotAllowed).Name), tpl, form)
+		default:
+			ctx.ServerError("CreateUser", err)
+		}
+		return
+	}
+	log.Trace("Account created: %s", u.Name)
+	return true
+}
+
+// handleUserCreated does additional steps after a new user is created.
+// It auto-sets admin for the only user, updates the optional external user and
+// sends a confirmation email if required.
+func handleUserCreated(ctx *context.Context, u *models.User, gothUser *goth.User) (ok bool) {
+	// Auto-set admin for the only user.
+	if models.CountUsers() == 1 {
+		u.IsAdmin = true
+		u.IsActive = true
+		u.SetLastLogin()
+		if err := models.UpdateUserCols(u, "is_admin", "is_active", "last_login_unix"); err != nil {
+			ctx.ServerError("UpdateUser", err)
+			return
+		}
+	}
+
+	// update external user information
+	if gothUser != nil {
+		if err := models.UpdateExternalUser(u, *gothUser); err != nil {
+			log.Error("UpdateExternalUser failed: %v", err)
+		}
+	}
+
+	// Send confirmation email
+	if !u.IsActive && u.ID > 1 {
+		mailer.SendActivateAccountMail(ctx.Locale, u)
+
+		ctx.Data["IsSendRegisterMail"] = true
+		ctx.Data["Email"] = u.Email
+		ctx.Data["ActiveCodeLives"] = timeutil.MinutesToFriendly(setting.Service.ActiveCodeLives, ctx.Locale.Language())
+		ctx.HTML(http.StatusOK, TplActivate)
+
+		if err := ctx.Cache.Put("MailResendLimit_"+u.LowerName, u.LowerName, 180); err != nil {
+			log.Error("Set cache(MailResendLimit) fail: %v", err)
+		}
+		return
+	}
+
+	return true
+}
+
+// Activate render activate user page
+func Activate(ctx *context.Context) {
+	code := ctx.Query("code")
+
+	if len(code) == 0 {
+		ctx.Data["IsActivatePage"] = true
+		if ctx.User == nil || ctx.User.IsActive {
+			ctx.NotFound("invalid user", nil)
+			return
+		}
+		// Resend confirmation email.
+		if setting.Service.RegisterEmailConfirm {
+			if ctx.Cache.IsExist("MailResendLimit_" + ctx.User.LowerName) {
+				ctx.Data["ResendLimited"] = true
+			} else {
+				ctx.Data["ActiveCodeLives"] = timeutil.MinutesToFriendly(setting.Service.ActiveCodeLives, ctx.Locale.Language())
+				mailer.SendActivateAccountMail(ctx.Locale, ctx.User)
+
+				if err := ctx.Cache.Put("MailResendLimit_"+ctx.User.LowerName, ctx.User.LowerName, 180); err != nil {
+					log.Error("Set cache(MailResendLimit) fail: %v", err)
+				}
+			}
+		} else {
+			ctx.Data["ServiceNotEnabled"] = true
+		}
+		ctx.HTML(http.StatusOK, TplActivate)
+		return
+	}
+
+	user := models.VerifyUserActiveCode(code)
+	// if code is wrong
+	if user == nil {
+		ctx.Data["IsActivateFailed"] = true
+		ctx.HTML(http.StatusOK, TplActivate)
+		return
+	}
+
+	// if account is local account, verify password
+	if user.LoginSource == 0 {
+		ctx.Data["Code"] = code
+		ctx.Data["NeedsPassword"] = true
+		ctx.HTML(http.StatusOK, TplActivate)
+		return
+	}
+
+	handleAccountActivation(ctx, user)
+}
+
+// ActivatePost handles account activation with password check
+func ActivatePost(ctx *context.Context) {
+	code := ctx.Query("code")
+	if len(code) == 0 {
+		ctx.Redirect(setting.AppSubURL + "/user/activate")
+		return
+	}
+
+	user := models.VerifyUserActiveCode(code)
+	// if code is wrong
+	if user == nil {
+		ctx.Data["IsActivateFailed"] = true
+		ctx.HTML(http.StatusOK, TplActivate)
+		return
+	}
+
+	// if account is local account, verify password
+	if user.LoginSource == 0 {
+		password := ctx.Query("password")
+		if len(password) == 0 {
+			ctx.Data["Code"] = code
+			ctx.Data["NeedsPassword"] = true
+			ctx.HTML(http.StatusOK, TplActivate)
+			return
+		}
+		if !user.ValidatePassword(password) {
+			ctx.Data["IsActivateFailed"] = true
+			ctx.HTML(http.StatusOK, TplActivate)
+			return
+		}
+	}
+
+	handleAccountActivation(ctx, user)
+}
+
+func handleAccountActivation(ctx *context.Context, user *models.User) {
+	user.IsActive = true
+	var err error
+	if user.Rands, err = models.GetUserSalt(); err != nil {
+		ctx.ServerError("UpdateUser", err)
+		return
+	}
+	if err := models.UpdateUserCols(user, "is_active", "rands"); err != nil {
+		if models.IsErrUserNotExist(err) {
+			ctx.NotFound("UpdateUserCols", err)
+		} else {
+			ctx.ServerError("UpdateUser", err)
+		}
+		return
+	}
+
+	log.Trace("User activated: %s", user.Name)
+
+	if err := ctx.Session.Set("uid", user.ID); err != nil {
+		log.Error(fmt.Sprintf("Error setting uid in session: %v", err))
+	}
+	if err := ctx.Session.Set("uname", user.Name); err != nil {
+		log.Error(fmt.Sprintf("Error setting uname in session: %v", err))
+	}
+	if err := ctx.Session.Release(); err != nil {
+		log.Error("Error storing session: %v", err)
+	}
+
+	ctx.Flash.Success(ctx.Tr("auth.account_activated"))
+	ctx.Redirect(setting.AppSubURL + "/")
+}
+
+// ActivateEmail render the activate email page
+func ActivateEmail(ctx *context.Context) {
+	code := ctx.Query("code")
+	emailStr := ctx.Query("email")
+
+	// Verify code.
+	if email := models.VerifyActiveEmailCode(code, emailStr); email != nil {
+		if err := email.Activate(); err != nil {
+			ctx.ServerError("ActivateEmail", err)
+		}
+
+		log.Trace("Email activated: %s", email.Email)
+		ctx.Flash.Success(ctx.Tr("settings.add_email_success"))
+
+		if u, err := models.GetUserByID(email.UID); err != nil {
+			log.Warn("GetUserByID: %d", email.UID)
+		} else {
+			// Allow user to validate more emails
+			_ = ctx.Cache.Delete("MailResendLimit_" + u.LowerName)
+		}
+	}
+
+	// FIXME: e-mail verification does not require the user to be logged in,
+	// so this could be redirecting to the login page.
+	// Should users be logged in automatically here? (consider 2FA requirements, etc.)
+	ctx.Redirect(setting.AppSubURL + "/user/settings/account")
+}
+
+// ForgotPasswd render the forget pasword page
+func ForgotPasswd(ctx *context.Context) {
+	ctx.Data["Title"] = ctx.Tr("auth.forgot_password_title")
+
+	if setting.MailService == nil {
+		ctx.Data["IsResetDisable"] = true
+		ctx.HTML(http.StatusOK, tplForgotPassword)
+		return
+	}
+
+	email := ctx.Query("email")
+	ctx.Data["Email"] = email
+
+	ctx.Data["IsResetRequest"] = true
+	ctx.HTML(http.StatusOK, tplForgotPassword)
+}
+
+// ForgotPasswdPost response for forget password request
+func ForgotPasswdPost(ctx *context.Context) {
+	ctx.Data["Title"] = ctx.Tr("auth.forgot_password_title")
+
+	if setting.MailService == nil {
+		ctx.NotFound("ForgotPasswdPost", nil)
+		return
+	}
+	ctx.Data["IsResetRequest"] = true
+
+	email := ctx.Query("email")
+	ctx.Data["Email"] = email
+
+	u, err := models.GetUserByEmail(email)
+	if err != nil {
+		if models.IsErrUserNotExist(err) {
+			ctx.Data["ResetPwdCodeLives"] = timeutil.MinutesToFriendly(setting.Service.ResetPwdCodeLives, ctx.Locale.Language())
+			ctx.Data["IsResetSent"] = true
+			ctx.HTML(http.StatusOK, tplForgotPassword)
+			return
+		}
+
+		ctx.ServerError("user.ResetPasswd(check existence)", err)
+		return
+	}
+
+	if !u.IsLocal() && !u.IsOAuth2() {
+		ctx.Data["Err_Email"] = true
+		ctx.RenderWithErr(ctx.Tr("auth.non_local_account"), tplForgotPassword, nil)
+		return
+	}
+
+	if ctx.Cache.IsExist("MailResendLimit_" + u.LowerName) {
+		ctx.Data["ResendLimited"] = true
+		ctx.HTML(http.StatusOK, tplForgotPassword)
+		return
+	}
+
+	mailer.SendResetPasswordMail(u)
+
+	if err = ctx.Cache.Put("MailResendLimit_"+u.LowerName, u.LowerName, 180); err != nil {
+		log.Error("Set cache(MailResendLimit) fail: %v", err)
+	}
+
+	ctx.Data["ResetPwdCodeLives"] = timeutil.MinutesToFriendly(setting.Service.ResetPwdCodeLives, ctx.Locale.Language())
+	ctx.Data["IsResetSent"] = true
+	ctx.HTML(http.StatusOK, tplForgotPassword)
+}
+
+func commonResetPassword(ctx *context.Context) (*models.User, *models.TwoFactor) {
+	code := ctx.Query("code")
+
+	ctx.Data["Title"] = ctx.Tr("auth.reset_password")
+	ctx.Data["Code"] = code
+
+	if nil != ctx.User {
+		ctx.Data["user_signed_in"] = true
+	}
+
+	if len(code) == 0 {
+		ctx.Flash.Error(ctx.Tr("auth.invalid_code"))
+		return nil, nil
+	}
+
+	// Fail early, don't frustrate the user
+	u := models.VerifyUserActiveCode(code)
+	if u == nil {
+		ctx.Flash.Error(ctx.Tr("auth.invalid_code"))
+		return nil, nil
+	}
+
+	twofa, err := models.GetTwoFactorByUID(u.ID)
+	if err != nil {
+		if !models.IsErrTwoFactorNotEnrolled(err) {
+			ctx.Error(http.StatusInternalServerError, "CommonResetPassword", err.Error())
+			return nil, nil
+		}
+	} else {
+		ctx.Data["has_two_factor"] = true
+		ctx.Data["scratch_code"] = ctx.QueryBool("scratch_code")
+	}
+
+	// Show the user that they are affecting the account that they intended to
+	ctx.Data["user_email"] = u.Email
+
+	if nil != ctx.User && u.ID != ctx.User.ID {
+		ctx.Flash.Error(ctx.Tr("auth.reset_password_wrong_user", ctx.User.Email, u.Email))
+		return nil, nil
+	}
+
+	return u, twofa
+}
+
+// ResetPasswd render the account recovery page
+func ResetPasswd(ctx *context.Context) {
+	ctx.Data["IsResetForm"] = true
+
+	commonResetPassword(ctx)
+	if ctx.Written() {
+		return
+	}
+
+	ctx.HTML(http.StatusOK, tplResetPassword)
+}
+
+// ResetPasswdPost response from account recovery request
+func ResetPasswdPost(ctx *context.Context) {
+	u, twofa := commonResetPassword(ctx)
+	if ctx.Written() {
+		return
+	}
+
+	if u == nil {
+		// Flash error has been set
+		ctx.HTML(http.StatusOK, tplResetPassword)
+		return
+	}
+
+	// Validate password length.
+	passwd := ctx.Query("password")
+	if len(passwd) < setting.MinPasswordLength {
+		ctx.Data["IsResetForm"] = true
+		ctx.Data["Err_Password"] = true
+		ctx.RenderWithErr(ctx.Tr("auth.password_too_short", setting.MinPasswordLength), tplResetPassword, nil)
+		return
+	} else if !password.IsComplexEnough(passwd) {
+		ctx.Data["IsResetForm"] = true
+		ctx.Data["Err_Password"] = true
+		ctx.RenderWithErr(password.BuildComplexityError(ctx), tplResetPassword, nil)
+		return
+	} else if pwned, err := password.IsPwned(ctx, passwd); pwned || err != nil {
+		errMsg := ctx.Tr("auth.password_pwned")
+		if err != nil {
+			log.Error(err.Error())
+			errMsg = ctx.Tr("auth.password_pwned_err")
+		}
+		ctx.Data["IsResetForm"] = true
+		ctx.Data["Err_Password"] = true
+		ctx.RenderWithErr(errMsg, tplResetPassword, nil)
+		return
+	}
+
+	// Handle two-factor
+	regenerateScratchToken := false
+	if twofa != nil {
+		if ctx.QueryBool("scratch_code") {
+			if !twofa.VerifyScratchToken(ctx.Query("token")) {
+				ctx.Data["IsResetForm"] = true
+				ctx.Data["Err_Token"] = true
+				ctx.RenderWithErr(ctx.Tr("auth.twofa_scratch_token_incorrect"), tplResetPassword, nil)
+				return
+			}
+			regenerateScratchToken = true
+		} else {
+			passcode := ctx.Query("passcode")
+			ok, err := twofa.ValidateTOTP(passcode)
+			if err != nil {
+				ctx.Error(http.StatusInternalServerError, "ValidateTOTP", err.Error())
+				return
+			}
+			if !ok || twofa.LastUsedPasscode == passcode {
+				ctx.Data["IsResetForm"] = true
+				ctx.Data["Err_Passcode"] = true
+				ctx.RenderWithErr(ctx.Tr("auth.twofa_passcode_incorrect"), tplResetPassword, nil)
+				return
+			}
+
+			twofa.LastUsedPasscode = passcode
+			if err = models.UpdateTwoFactor(twofa); err != nil {
+				ctx.ServerError("ResetPasswdPost: UpdateTwoFactor", err)
+				return
+			}
+		}
+	}
+	var err error
+	if u.Rands, err = models.GetUserSalt(); err != nil {
+		ctx.ServerError("UpdateUser", err)
+		return
+	}
+	if err = u.SetPassword(passwd); err != nil {
+		ctx.ServerError("UpdateUser", err)
+		return
+	}
+	u.MustChangePassword = false
+	if err := models.UpdateUserCols(u, "must_change_password", "passwd", "passwd_hash_algo", "rands", "salt"); err != nil {
+		ctx.ServerError("UpdateUser", err)
+		return
+	}
+
+	log.Trace("User password reset: %s", u.Name)
+	ctx.Data["IsResetFailed"] = true
+	remember := len(ctx.Query("remember")) != 0
+
+	if regenerateScratchToken {
+		// Invalidate the scratch token.
+		_, err = twofa.GenerateScratchToken()
+		if err != nil {
+			ctx.ServerError("UserSignIn", err)
+			return
+		}
+		if err = models.UpdateTwoFactor(twofa); err != nil {
+			ctx.ServerError("UserSignIn", err)
+			return
+		}
+
+		handleSignInFull(ctx, u, remember, false)
+		ctx.Flash.Info(ctx.Tr("auth.twofa_scratch_used"))
+		ctx.Redirect(setting.AppSubURL + "/user/settings/security")
+		return
+	}
+
+	handleSignInFull(ctx, u, remember, true)
+}
+
+// MustChangePassword renders the page to change a user's password
+func MustChangePassword(ctx *context.Context) {
+	ctx.Data["Title"] = ctx.Tr("auth.must_change_password")
+	ctx.Data["ChangePasscodeLink"] = setting.AppSubURL + "/user/settings/change_password"
+	ctx.Data["MustChangePassword"] = true
+	ctx.HTML(http.StatusOK, tplMustChangePassword)
+}
+
+// MustChangePasswordPost response for updating a user's password after his/her
+// account was created by an admin
+func MustChangePasswordPost(ctx *context.Context) {
+	form := web.GetForm(ctx).(*forms.MustChangePasswordForm)
+	ctx.Data["Title"] = ctx.Tr("auth.must_change_password")
+	ctx.Data["ChangePasscodeLink"] = setting.AppSubURL + "/user/settings/change_password"
+	if ctx.HasError() {
+		ctx.HTML(http.StatusOK, tplMustChangePassword)
+		return
+	}
+	u := ctx.User
+	// Make sure only requests for users who are eligible to change their password via
+	// this method passes through
+	if !u.MustChangePassword {
+		ctx.ServerError("MustUpdatePassword", errors.New("cannot update password.. Please visit the settings page"))
+		return
+	}
+
+	if form.Password != form.Retype {
+		ctx.Data["Err_Password"] = true
+		ctx.RenderWithErr(ctx.Tr("form.password_not_match"), tplMustChangePassword, &form)
+		return
+	}
+
+	if len(form.Password) < setting.MinPasswordLength {
+		ctx.Data["Err_Password"] = true
+		ctx.RenderWithErr(ctx.Tr("auth.password_too_short", setting.MinPasswordLength), tplMustChangePassword, &form)
+		return
+	}
+
+	var err error
+	if err = u.SetPassword(form.Password); err != nil {
+		ctx.ServerError("UpdateUser", err)
+		return
+	}
+
+	u.MustChangePassword = false
+
+	if err := models.UpdateUserCols(u, "must_change_password", "passwd", "passwd_hash_algo", "salt"); err != nil {
+		ctx.ServerError("UpdateUser", err)
+		return
+	}
+
+	ctx.Flash.Success(ctx.Tr("settings.change_password_success"))
+
+	log.Trace("User updated password: %s", u.Name)
+
+	if redirectTo := ctx.GetCookie("redirect_to"); len(redirectTo) > 0 && !utils.IsExternalURL(redirectTo) {
+		middleware.DeleteRedirectToCookie(ctx.Resp)
+		ctx.RedirectToFirst(redirectTo)
+		return
+	}
+
+	ctx.Redirect(setting.AppSubURL + "/")
+}