fix(ldap): pass through LDAP mail attribute instead of crafting email (tinyauthapp#834)

* fix(ldap): pass through LDAP mail attribute instead of crafting email

TinyAuth was constructing LDAP user emails as username@CookieDomain
instead of using the mail attribute stored in the directory. This caused
OIDC clients like Grafana to receive a synthetic email rather than the
real one.

Rename GetUserDN to GetUserInfo and extend it to also fetch the mail
attribute in the same LDAP query. Thread the result through UserSearch
and use it in both the login flow and the basic auth middleware, falling
back to the crafted email only when LDAP returns no mail value.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

* chore: add ldap email logic back after main merge

---------

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
Co-authored-by: Stavros <steveiliop56@gmail.com>

Author: 3 people

internal/controller/user_controller.go

@@ -189,6 +189,9 @@ func (controller *UserController) loginHandler(c *gin.Context) {
 
 	if search.Type == model.UserLDAP {
 		sessionCookie.Provider = "ldap"
+		if search.Email != "" {
+			sessionCookie.Email = search.Email
+		}
 	}
 
 	cookie, err := controller.auth.CreateSession(c, sessionCookie)

internal/middleware/context_middleware.go

@@ -160,7 +160,12 @@ func (m *ContextMiddleware) cookieAuth(ctx context.Context, uuid string) (*model
 
 		userContext.LDAP.Groups = user.Groups
 		userContext.LDAP.Name = utils.Capitalize(userContext.LDAP.Username)
+
 		userContext.LDAP.Email = utils.CompileUserEmail(userContext.LDAP.Username, m.runtime.CookieDomain)
+		if search.Email != "" {
+			userContext.LDAP.Email = search.Email
+		}
+
 	case model.ProviderOAuth:
 		_, exists := m.broker.GetService(userContext.OAuth.ID)
 
@@ -238,11 +243,15 @@ func (m *ContextMiddleware) basicAuth(username string, password string) (*model.
 			BaseContext: model.BaseContext{
 				Username: username,
 				Name:     utils.Capitalize(username),
-				Email:    utils.CompileUserEmail(username, m.runtime.CookieDomain),
 			},
 			Groups: user.Groups,
 		}
 		userContext.Provider = model.ProviderLDAP
+
+		userContext.LDAP.Email = utils.CompileUserEmail(username, m.runtime.CookieDomain)
+		if search.Email != "" {
+			userContext.LDAP.Email = search.Email
+		}
 	}
 
 	userContext.Authenticated = true

internal/model/users.go

@@ -21,5 +21,6 @@ type LocalUser struct {
 
 type UserSearch struct {
 	Username string
+	Email    string // used for LDAP, we can't throw it to LDAPUser because it would need another cache or an LDAP lookup every time
 	Type     UserSearchType
 }

internal/service/auth_service.go

@@ -130,14 +130,15 @@ func (auth *AuthService) SearchUser(username string) (*model.UserSearch, error)
 	}
 
 	if auth.ldap != nil {
-		userDN, err := auth.ldap.GetUserDN(username)
+		userDN, email, err := auth.ldap.GetUserInfo(username)
 
 		if err != nil {
 			return nil, fmt.Errorf("failed to get ldap user: %w", err)
 		}
 
 		return &model.UserSearch{
 			Username: userDN,
+			Email:    email,
 			Type:     model.UserLDAP,
 		}, nil
 	}

internal/service/ldap_service.go

@@ -134,16 +134,15 @@ func (ldap *LdapService) connect() (*ldapgo.Conn, error) {
 	return ldap.conn, nil
 }
 
-func (ldap *LdapService) GetUserDN(username string) (string, error) {
-	// Escape the username to prevent LDAP injection
+func (ldap *LdapService) GetUserInfo(username string) (dn string, email string, err error) {
 	escapedUsername := ldapgo.EscapeFilter(username)
 	filter := fmt.Sprintf(ldap.config.LDAP.SearchFilter, escapedUsername)
 
 	searchRequest := ldapgo.NewSearchRequest(
 		ldap.config.LDAP.BaseDN,
 		ldapgo.ScopeWholeSubtree, ldapgo.NeverDerefAliases, 0, 0, false,
 		filter,
-		[]string{"dn"},
+		[]string{"dn", "mail"},
 		nil,
 	)
 
@@ -152,15 +151,15 @@ func (ldap *LdapService) GetUserDN(username string) (string, error) {
 
 	searchResult, err := ldap.conn.Search(searchRequest)
 	if err != nil {
-		return "", err
+		return "", "", err
 	}
 
 	if len(searchResult.Entries) != 1 {
-		return "", fmt.Errorf("multiple or no entries found for user %s", username)
+		return "", "", fmt.Errorf("multiple or no entries found for user %s", username)
 	}
 
-	userDN := searchResult.Entries[0].DN
-	return userDN, nil
+	entry := searchResult.Entries[0]
+	return entry.DN, entry.GetAttributeValue("mail"), nil
 }
 
 func (ldap *LdapService) GetUserGroups(userDN string) ([]string, error) {