Refactor regexp node labels.

gravitational · Sep 29, 2018 · cbb9598 · cbb9598
1 parent 480eb23
commit cbb9598
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Showing 2 changed files with 9 additions and 4 deletions.
diff --git a/lib/services/role.go b/lib/services/role.go
@@ -1401,7 +1401,6 @@ func MatchLabels(selector Labels, target map[string]string) (bool, string, error
 		return false, "no match, empty selector", nil
 	}
 
-	// matchLabels, labelsMessage := MatchLabels(role.GetNodeLabels(Deny), s.GetAllLabels())
 	// *: * matches everything even empty target set.
 	selectorValues := selector[Wildcard]
 	if len(selectorValues) == 1 && selectorValues[0] == Wildcard {
@@ -1419,7 +1418,7 @@ func MatchLabels(selector Labels, target map[string]string) (bool, string, error
 		if !utils.SliceContainsStr(selectorValues, Wildcard) {
 			result, err := utils.SliceContainsRegexStr(targetVal, selectorValues)
 			if err != nil {
-				return false, "", trace.BadParameter(err.Error())
+				return false, "", trace.Wrap(err)
 			} else if !result {
 				return false, fmt.Sprintf("no value match: got '%v' want: '%v'", targetVal, selectorValues), nil
 			}
@@ -1568,7 +1567,7 @@ func (set RoleSet) CheckAccessToServer(login string, s Server) error {
 		matchNamespace, namespaceMessage := MatchNamespace(role.GetNamespaces(Deny), s.GetNamespace())
 		matchLabels, labelsMessage, err := MatchLabels(role.GetNodeLabels(Deny), s.GetAllLabels())
 		if err != nil {
-			return trace.CompareFailed(err.Error())
+			return trace.Wrap(err)
 		}
 		matchLogin, loginMessage := MatchLogin(role.GetLogins(Deny), login)
 		if matchNamespace && (matchLabels || matchLogin) {
@@ -1588,7 +1587,7 @@ func (set RoleSet) CheckAccessToServer(login string, s Server) error {
 		matchNamespace, namespaceMessage := MatchNamespace(role.GetNamespaces(Allow), s.GetNamespace())
 		matchLabels, labelsMessage, err := MatchLabels(role.GetNodeLabels(Allow), s.GetAllLabels())
 		if err != nil {
-			return trace.CompareFailed(err.Error())
+			return trace.Wrap(err)
 		}
 		matchLogin, loginMessage := MatchLogin(role.GetLogins(Allow), login)
 		if matchNamespace && matchLabels && matchLogin {

diff --git a/lib/utils/replace.go b/lib/utils/replace.go
@@ -46,6 +46,8 @@ func ReplaceRegexp(expression string, replaceWith string, input string) (string,
 	return expr.ReplaceAllString(input, replaceWith), nil
 }
 
+// SliceContainsRegexStr checks if input matches any of the expressions. The
+// match is always evaluated as a regex either an exact match or regexp.
 func SliceContainsRegexStr(input string, expressions []string) (bool, error) {
 	for _, expression := range expressions {
 		if !strings.HasPrefix(expression, "^") || !strings.HasSuffix(expression, "$") {
@@ -59,6 +61,10 @@ func SliceContainsRegexStr(input string, expressions []string) (bool, error) {
 		if err != nil {
 			return false, trace.BadParameter(err.Error())
 		}
+
+		// Since the expression is always surrounded by ^ and $ this is an exact
+		// match for either a a plain string (for example ^hello$) or for a regexp
+		// (for example ^hel*o$).
 		if expr.MatchString(input) {
 			return true, nil
 		}