Unify two factor check (#27915) (#27929)

Backport #27915 by @KN4CK3R

Fixes #27819

We have support for two factor logins with the normal web login and with
basic auth. For basic auth the two factor check was implemented at three
different places and you need to know that this check is necessary. This
PR moves the check into the basic auth itself.

Co-authored-by: KN4CK3R <admin@oldschoolhack.me>

modules/context/api.go

@@ -11,7 +11,6 @@ import (
 	"net/url"
 	"strings"
 
-	"code.gitea.io/gitea/models/auth"
 	repo_model "code.gitea.io/gitea/models/repo"
 	"code.gitea.io/gitea/models/unit"
 	user_model "code.gitea.io/gitea/models/user"
@@ -205,32 +204,6 @@ func (ctx *APIContext) SetLinkHeader(total, pageSize int) {
 	}
 }
 
-// CheckForOTP validates OTP
-func (ctx *APIContext) CheckForOTP() {
-	if skip, ok := ctx.Data["SkipLocalTwoFA"]; ok && skip.(bool) {
-		return // Skip 2FA
-	}
-
-	otpHeader := ctx.Req.Header.Get("X-Gitea-OTP")
-	twofa, err := auth.GetTwoFactorByUID(ctx, ctx.Doer.ID)
-	if err != nil {
-		if auth.IsErrTwoFactorNotEnrolled(err) {
-			return // No 2FA enrollment for this user
-		}
-		ctx.Error(http.StatusInternalServerError, "GetTwoFactorByUID", err)
-		return
-	}
-	ok, err := twofa.ValidateTOTP(otpHeader)
-	if err != nil {
-		ctx.Error(http.StatusInternalServerError, "ValidateTOTP", err)
-		return
-	}
-	if !ok {
-		ctx.Error(http.StatusUnauthorized, "", nil)
-		return
-	}
-}
-
 // APIContexter returns apicontext as middleware
 func APIContexter() func(http.Handler) http.Handler {
 	return func(next http.Handler) http.Handler {