diff --git a/hscontrol/types/users.go b/hscontrol/types/users.go
index f983d7f5..d0a7c19b 100644
--- a/hscontrol/types/users.go
+++ b/hscontrol/types/users.go
@@ -2,6 +2,8 @@ package types
 
 import (
 	"cmp"
+	"database/sql"
+	"net/mail"
 	"strconv"
 
 	v1 "github.com/juanfont/headscale/gen/go/headscale/v1"
@@ -22,19 +24,19 @@ type User struct {
 
 	// Username for the user, is used if email is empty
 	// Should not be used, please use Username().
-	Name string `gorm:"unique"`
+	Name sql.NullString `gorm:"unique"`
 
 	// Typically the full name of the user
 	DisplayName string
 
 	// Email of the user
 	// Should not be used, please use Username().
-	Email string
+	Email sql.NullString
 
 	// Unique identifier of the user from OIDC,
 	// comes from `sub` claim in the OIDC token
 	// and is used to lookup the user.
-	ProviderIdentifier string `gorm:"index"`
+	ProviderIdentifier sql.NullString `gorm:"index"`
 
 	// Provider is the origin of the user account,
 	// same as RegistrationMethod, without authkey.
@@ -51,7 +53,7 @@ type User struct {
 // should be used throughout headscale, in information returned to the
 // user and the Policy engine.
 func (u *User) Username() string {
-	return cmp.Or(u.Email, u.Name, u.ProviderIdentifier, strconv.FormatUint(uint64(u.ID), 10))
+	return cmp.Or(u.Email.String, u.Name.String, u.ProviderIdentifier.String, strconv.FormatUint(uint64(u.ID), 10))
 }
 
 // DisplayNameOrUsername returns the DisplayName if it exists, otherwise
@@ -103,11 +105,11 @@ func (u *User) TailscaleUserProfile() tailcfg.UserProfile {
 func (u *User) Proto() *v1.User {
 	return &v1.User{
 		Id:            strconv.FormatUint(uint64(u.ID), util.Base10),
-		Name:          u.Name,
+		Name:          u.Name.String,
 		CreatedAt:     timestamppb.New(u.CreatedAt),
 		DisplayName:   u.DisplayName,
-		Email:         u.Email,
-		ProviderId:    u.ProviderIdentifier,
+		Email:         u.Email.String,
+		ProviderId:    u.ProviderIdentifier.String,
 		Provider:      u.Provider,
 		ProfilePicUrl: u.ProfilePicURL,
 	}
@@ -129,10 +131,20 @@ type OIDCClaims struct {
 // FromClaim overrides a User from OIDC claims.
 // All fields will be updated, except for the ID.
 func (u *User) FromClaim(claims *OIDCClaims) {
-	u.ProviderIdentifier = claims.Sub
+	err := util.CheckForFQDNRules(claims.Username)
+	if err == nil {
+		u.Name.String = claims.Username
+	}
+
+	if claims.EmailVerified {
+		_, err = mail.ParseAddress(claims.Email)
+		if err == nil {
+			u.Email.String = claims.Email
+		}
+	}
+
+	u.ProviderIdentifier.String = claims.Sub
 	u.DisplayName = claims.Name
-	u.Email = claims.Email
-	u.Name = claims.Username
 	u.ProfilePicURL = claims.ProfilePictureURL
 	u.Provider = util.RegisterMethodOIDC
 }