add the possibility to debug oauth or oidc login issues (#541)

docs/documentation/configuration/overview.md

@@ -512,13 +512,18 @@ Below are the properties for each OIDC provider entry inside `auth.oidc`:
     - `admin_group_regex`: A regular expression to match the `user_groups` claim. Each entry in the `user_groups` claim is checked against this regex.
 
 #### `registration_enabled`
-- **Default:** *(empty)*
+- **Default:** `false`
 - **Description:** If `true`, a new user will be created in WireGuard Portal if not already present.
 
 #### `log_user_info`
-- **Default:** *(empty)*
+- **Default:** `false`
 - **Description:** If `true`, OIDC user data is logged at the trace level upon login (for debugging).
 
+#### `log_sensitive_info`
+- **Default:** `false`
+- **Description:** If `true`, sensitive OIDC user data, such as tokens and raw responses, will be logged at the trace level upon login (for debugging).
+- **Important:** Keep this setting disabled in production environments! Remove logs once you finished debugging authentication issues.
+
 ---
 
 ### OAuth
@@ -585,13 +590,18 @@ Below are the properties for each OAuth provider entry inside `auth.oauth`:
   - `admin_group_regex`: A regular expression to match the `user_groups` claim. Each entry in the `user_groups` claim is checked against this regex.
 
 #### `registration_enabled`
-- **Default:** *(empty)*
+- **Default:** `false`
 - **Description:** If `true`, new users are created automatically on successful login.
 
 #### `log_user_info`
-- **Default:** *(empty)*
+- **Default:** `false`
 - **Description:** If `true`, logs user info at the trace level upon login.
 
+#### `log_sensitive_info`
+- **Default:** `false`
+- **Description:** If `true`, sensitive OIDC user data, such as tokens and raw responses, will be logged at the trace level upon login (for debugging).
+- **Important:** Keep this setting disabled in production environments! Remove logs once you finished debugging authentication issues.
+
 ---
 
 ### LDAP
@@ -608,11 +618,11 @@ Below are the properties for each LDAP provider entry inside `auth.ldap`:
 - **Description:** The LDAP server URL (e.g., `ldap://srv-ad01.company.local:389`).
 
 #### `start_tls`
-- **Default:** *(empty)*
+- **Default:** `false`
 - **Description:** If `true`, use STARTTLS to secure the LDAP connection.
 
 #### `cert_validation`
-- **Default:** *(empty)*
+- **Default:** `false`
 - **Description:** If `true`, validate the LDAP server’s TLS certificate.
 
 #### `tls_certificate_path`
@@ -682,19 +692,19 @@ Below are the properties for each LDAP provider entry inside `auth.ldap`:
   ```
 
 #### `disable_missing`
-- **Default:** *(empty)*
+- **Default:** `false`
 - **Description:** If `true`, any user **not** found in LDAP (during sync) is disabled in WireGuard Portal.
 
 #### `auto_re_enable`
-- **Default:** *(empty)*
+- **Default:** `false`
 - **Description:** If `true`, users that where disabled because they were missing (see `disable_missing`) will be re-enabled once they are found again.
 
 #### `registration_enabled`
-- **Default:** *(empty)*
+- **Default:** `false`
 - **Description:** If `true`, new user accounts are created in WireGuard Portal upon first login.
 
 #### `log_user_info`
-- **Default:** *(empty)*
+- **Default:** `false`
 - **Description:** If `true`, logs LDAP user data at the trace level upon login.
 
 ---

internal/app/auth/auth_oauth.go

@@ -27,6 +27,7 @@ type PlainOauthAuthenticator struct {
 	userAdminMapping     *config.OauthAdminMapping
 	registrationEnabled  bool
 	userInfoLogging      bool
+	sensitiveInfoLogging bool
 	allowedDomains       []string
 }
 
@@ -57,6 +58,7 @@ func newPlainOauthAuthenticator(
 	provider.userAdminMapping = &cfg.AdminMapping
 	provider.registrationEnabled = cfg.RegistrationEnabled
 	provider.userInfoLogging = cfg.LogUserInfo
+	provider.sensitiveInfoLogging = cfg.LogSensitiveInfo
 	provider.allowedDomains = cfg.AllowedDomains
 
 	return provider, nil
@@ -110,6 +112,10 @@ func (p PlainOauthAuthenticator) GetUserInfo(
 
 	response, err := p.client.Do(req)
 	if err != nil {
+		if p.sensitiveInfoLogging {
+			slog.Debug("OAuth: failed to get user info", "endpoint", p.userInfoEndpoint,
+				"token", token, "error", err)
+		}
 		return nil, fmt.Errorf("failed to get user info: %w", err)
 	}
 	defer internal.LogClose(response.Body)
@@ -121,11 +127,15 @@ func (p PlainOauthAuthenticator) GetUserInfo(
 	var userFields map[string]any
 	err = json.Unmarshal(contents, &userFields)
 	if err != nil {
+		if p.sensitiveInfoLogging {
+			slog.Debug("OAuth: failed to parse user info", "endpoint", p.userInfoEndpoint,
+				"token", token, "contents", contents, "error", err)
+		}
 		return nil, fmt.Errorf("failed to parse user info: %w", err)
 	}
 
 	if p.userInfoLogging {
-		slog.Debug("OAuth user info",
+		slog.Debug("OAuth: user info debug",
 			"source", p.name,
 			"info", string(contents))
 	}

internal/app/auth/auth_oidc.go

@@ -24,6 +24,7 @@ type OidcAuthenticator struct {
 	userAdminMapping     *config.OauthAdminMapping
 	registrationEnabled  bool
 	userInfoLogging      bool
+	sensitiveInfoLogging bool
 	allowedDomains       []string
 }
 
@@ -58,6 +59,7 @@ func newOidcAuthenticator(
 	provider.userAdminMapping = &cfg.AdminMapping
 	provider.registrationEnabled = cfg.RegistrationEnabled
 	provider.userInfoLogging = cfg.LogUserInfo
+	provider.sensitiveInfoLogging = cfg.LogSensitiveInfo
 	provider.allowedDomains = cfg.AllowedDomains
 
 	return provider, nil
@@ -102,24 +104,40 @@ func (o OidcAuthenticator) GetUserInfo(ctx context.Context, token *oauth2.Token,
 ) {
 	rawIDToken, ok := token.Extra("id_token").(string)
 	if !ok {
+		if o.sensitiveInfoLogging {
+			slog.Debug("OIDC: token does not contain id_token", "token", token, "nonce", nonce)
+		}
 		return nil, errors.New("token does not contain id_token")
 	}
 	idToken, err := o.verifier.Verify(ctx, rawIDToken)
 	if err != nil {
+		if o.sensitiveInfoLogging {
+			slog.Debug("OIDC: failed to validate id_token", "token", token, "id_token", rawIDToken, "nonce", nonce,
+				"error",
+				err)
+		}
 		return nil, fmt.Errorf("failed to validate id_token: %w", err)
 	}
 	if idToken.Nonce != nonce {
+		if o.sensitiveInfoLogging {
+			slog.Debug("OIDC: id_token nonce mismatch", "token", token, "id_token", idToken, "nonce", nonce)
+		}
 		return nil, errors.New("nonce mismatch")
 	}
 
 	var tokenFields map[string]any
 	if err = idToken.Claims(&tokenFields); err != nil {
+		if o.sensitiveInfoLogging {
+			slog.Debug("OIDC: failed to parse extra claims", "token", token, "id_token", idToken, "nonce", nonce,
+				"error",
+				err)
+		}
 		return nil, fmt.Errorf("failed to parse extra claims: %w", err)
 	}
 
 	if o.userInfoLogging {
 		contents, _ := json.Marshal(tokenFields)
-		slog.Debug("OIDC user info",
+		slog.Debug("OIDC: user info debug",
 			"source", o.name,
 			"info", string(contents))
 	}

internal/config/auth.go

@@ -211,6 +211,10 @@ type OpenIDConnectProvider struct {
 
 	// If LogUserInfo is set to true, the user info retrieved from the OIDC provider will be logged in trace level.
 	LogUserInfo bool `yaml:"log_user_info"`
+
+	// If LogSensitiveInfo is set to true, sensitive information retrieved from the OIDC provider will be logged in trace level.
+	// This also includes OAuth tokens! Keep this disabled in production!
+	LogSensitiveInfo bool `yaml:"log_sensitive_info"`
 }
 
 // OAuthProvider contains the configuration for the OAuth provider.
@@ -252,6 +256,10 @@ type OAuthProvider struct {
 
 	// If LogUserInfo is set to true, the user info retrieved from the OAuth provider will be logged in trace level.
 	LogUserInfo bool `yaml:"log_user_info"`
+
+	// If LogSensitiveInfo is set to true, sensitive information retrieved from the OAuth provider will be logged in trace level.
+	// This also includes OAuth tokens! Keep this disabled in production!
+	LogSensitiveInfo bool `yaml:"log_sensitive_info"`
 }
 
 // WebauthnConfig contains the configuration for the WebAuthn authenticator.