From 246af92f5d8dab444b109df4f8f72069f6ac713b Mon Sep 17 00:00:00 2001
From: Meik <meik.drechsler@consulting4it.de>
Date: Sun, 29 Mar 2026 22:35:00 +0200
Subject: [PATCH] Add NTFS folder blacklist support

---
 LiamNtfs/C4IT.LIAM.Ntfs.cs | 116 +++++++++++++++++++++++++++++++++++--
 1 file changed, 112 insertions(+), 4 deletions(-)

diff --git a/LiamNtfs/C4IT.LIAM.Ntfs.cs b/LiamNtfs/C4IT.LIAM.Ntfs.cs
index 59bd96f..0c08329 100644
--- a/LiamNtfs/C4IT.LIAM.Ntfs.cs
+++ b/LiamNtfs/C4IT.LIAM.Ntfs.cs
@@ -371,7 +371,7 @@ namespace C4IT.LIAM
                 foreach (var childPath in GetServerRootChildPaths(parentClassification.NormalizedPath))
                 {
                     var childClassification = ClassifyPath(childPath);
-                    if (!ShouldIncludeDataArea(childClassification.DisplayName))
+                    if (!ShouldIncludeDataArea(childClassification))
                         continue;
 
                     var childDataArea = await BuildDataAreaAsync(childClassification);
@@ -393,7 +393,7 @@ namespace C4IT.LIAM
             foreach (var entry in folderEntries.Values.OfType<cNtfsResultFolder>())
             {
                 var childClassification = ClassifyPath(entry.Path);
-                if (!ShouldIncludeDataArea(childClassification.DisplayName))
+                if (!ShouldIncludeDataArea(childClassification))
                     continue;
 
                 var childDataArea = await BuildDataAreaAsync(childClassification, entry);
@@ -420,7 +420,26 @@ namespace C4IT.LIAM
                 .Select(shareName => BuildUncPath(new[] { serverName, shareName }, 2));
         }
 
-        private bool ShouldIncludeDataArea(string displayName)
+        private bool ShouldIncludeDataArea(cNtfsPathClassification classification)
+        {
+            if (classification == null)
+                return false;
+
+            if (!MatchesDataAreaRegEx(classification.DisplayName))
+                return false;
+
+            string matchingConfigurationKey;
+            string matchingRule;
+            if (IsBlacklistedFolderPath(classification, out matchingConfigurationKey, out matchingRule))
+            {
+                LogEntry($"Skip NTFS path '{classification.NormalizedPath}' due to AdditionalConfiguration rule '{matchingConfigurationKey}={matchingRule}'", LogLevels.Debug);
+                return false;
+            }
+
+            return true;
+        }
+
+        private bool MatchesDataAreaRegEx(string displayName)
         {
             if (string.IsNullOrEmpty(this.DataAreaRegEx))
                 return true;
@@ -428,6 +447,90 @@ namespace C4IT.LIAM
             return Regex.Match(displayName ?? string.Empty, this.DataAreaRegEx).Success;
         }
 
+        private bool IsBlacklistedFolderPath(cNtfsPathClassification classification, out string matchingConfigurationKey, out string matchingRule)
+        {
+            matchingConfigurationKey = null;
+            matchingRule = null;
+
+            if (classification == null || classification.Kind != eNtfsPathKind.Folder)
+                return false;
+
+            foreach (var excludedFolderName in GetAdditionalConfigurationValues("NtfsExcludeFolderNames"))
+            {
+                if (!MatchesAdditionalConfigurationPattern(classification.DisplayName, excludedFolderName))
+                    continue;
+
+                matchingConfigurationKey = "NtfsExcludeFolderNames";
+                matchingRule = excludedFolderName;
+                return true;
+            }
+
+            var relativePath = GetRelativePathFromRoot(classification.NormalizedPath);
+            foreach (var excludedRelativePath in GetAdditionalConfigurationValues("NtfsExcludeRelativePaths"))
+            {
+                if (!MatchesAdditionalConfigurationPattern(relativePath, excludedRelativePath))
+                    continue;
+
+                matchingConfigurationKey = "NtfsExcludeRelativePaths";
+                matchingRule = excludedRelativePath;
+                return true;
+            }
+
+            return false;
+        }
+
+        private IEnumerable<string> GetAdditionalConfigurationValues(string key)
+        {
+            if (AdditionalConfiguration == null || string.IsNullOrWhiteSpace(key))
+                return Enumerable.Empty<string>();
+
+            string rawValue;
+            if (!AdditionalConfiguration.TryGetValue(key, out rawValue) || string.IsNullOrWhiteSpace(rawValue))
+                return Enumerable.Empty<string>();
+
+            return rawValue
+                .Split(new[] { ';' }, StringSplitOptions.RemoveEmptyEntries)
+                .Select(i => i.Trim())
+                .Where(i => !string.IsNullOrWhiteSpace(i))
+                .Distinct(StringComparer.OrdinalIgnoreCase)
+                .ToList();
+        }
+
+        private string GetRelativePathFromRoot(string path)
+        {
+            var normalizedRoot = NormalizeUncPath(this.RootPath);
+            var normalizedPath = NormalizeUncPath(path);
+
+            if (string.IsNullOrWhiteSpace(normalizedRoot) || string.IsNullOrWhiteSpace(normalizedPath))
+                return string.Empty;
+
+            if (PathsEqual(normalizedRoot, normalizedPath))
+                return string.Empty;
+
+            var rootWithSeparator = normalizedRoot + "\\";
+            if (!normalizedPath.StartsWith(rootWithSeparator, StringComparison.OrdinalIgnoreCase))
+                return normalizedPath;
+
+            return normalizedPath.Substring(rootWithSeparator.Length)
+                .Trim()
+                .TrimStart('\\')
+                .Replace('/', '\\');
+        }
+
+        private bool MatchesAdditionalConfigurationPattern(string value, string pattern)
+        {
+            if (string.IsNullOrWhiteSpace(value) || string.IsNullOrWhiteSpace(pattern))
+                return false;
+
+            var normalizedValue = value.Trim().Replace('/', '\\');
+            var normalizedPattern = pattern.Trim().Replace('/', '\\').Trim('\\');
+            if (string.IsNullOrWhiteSpace(normalizedPattern))
+                return false;
+
+            var regexPattern = "^" + Regex.Escape(normalizedPattern).Replace("\\*", ".*") + "$";
+            return Regex.IsMatch(normalizedValue, regexPattern, RegexOptions.IgnoreCase | RegexOptions.CultureInvariant);
+        }
+
         private List<string> GetDfsObjectPrefixes(string path)
         {
             var normalizedPath = NormalizeUncPath(path);
@@ -739,7 +842,12 @@ namespace C4IT.LIAM
         public bool IsPermissionManagedFolderPath(string path)
         {
             var classification = ClassifyPath(path);
-            return classification != null && classification.Kind == eNtfsPathKind.Folder;
+            if (classification == null || classification.Kind != eNtfsPathKind.Folder)
+                return false;
+
+            string matchingConfigurationKey;
+            string matchingRule;
+            return !IsBlacklistedFolderPath(classification, out matchingConfigurationKey, out matchingRule);
         }
 
         private IEnumerable<IAM_SecurityGroupTemplate> BuildSecurityGroupTemplates()