Check signups against email domain blocklist

models/error.go

@@ -34,6 +34,21 @@ func (err ErrNamePatternNotAllowed) Error() string {
 	return fmt.Sprintf("name pattern is not allowed [pattern: %s]", err.Pattern)
 }
 
+type ErrBlockedDomain struct {
+	Email string
+}
+
+func IsErrBlockedDomain(err error) bool {
+	_, ok := err.(ErrBlockedDomain)
+	fmt.Printf("Error type is BlockedDomain: %t\n", ok)
+	return ok
+}
+
+func (err ErrBlockedDomain) Error() string {
+	// don't inform the user of the blocked domain
+	return fmt.Sprintf("user sign up failed")
+}
+
 //  ____ ___
 // |    |   \______ ___________
 // |    |   /  ___// __ \_  __ \

models/user.go

@@ -5,6 +5,7 @@
 package models
 
 import (
+	"bufio"
 	"bytes"
 	"container/list"
 	"crypto/sha256"
@@ -15,6 +16,7 @@ import (
 	_ "image/jpeg"
 	"image/png"
 	"os"
+	"path"
 	"path/filepath"
 	"strings"
 	"time"
@@ -492,6 +494,31 @@ func IsUserExist(uid int64, name string) (bool, error) {
 	return x.Where("id != ?", uid).Get(&User{LowerName: strings.ToLower(name)})
 }
 
+func IsBlockedDomain(email string) (bool, error) {
+	fpath := path.Join(setting.CustomPath, "blocklist")
+	if !com.IsExist(fpath) {
+		return false, nil
+	}
+
+	f, err := os.Open(fpath)
+	if err != nil {
+		log.Error(2, "Failed to open file %q: %v", fpath, err)
+		return false, nil
+	}
+	defer f.Close()
+
+	scanner := bufio.NewScanner(f)
+	for scanner.Scan() {
+		// Check provided email address against each line as suffix
+		if strings.HasSuffix(email, scanner.Text()) {
+			log.Trace("New user email matched blocked domain: %q", email)
+			return true, nil
+		}
+	}
+
+	return false, nil
+}
+
 // GetUserSalt returns a ramdom user salt token.
 func GetUserSalt() (string, error) {
 	return tool.RandomString(10)
@@ -561,6 +588,13 @@ func CreateUser(u *User) (err error) {
 		return ErrEmailAlreadyUsed{u.Email}
 	}
 
+	isBlocked, err := IsBlockedDomain(u.Email)
+	if err != nil {
+		return err
+	} else if isBlocked {
+		return ErrBlockedDomain{u.Email}
+	}
+
 	u.LowerName = strings.ToLower(u.Name)
 	u.AvatarEmail = u.Email
 	u.Avatar = tool.HashEmail(u.AvatarEmail)