From 89ce1e5ccaf12bc40ba25cc2fea1678e5362aba6 Mon Sep 17 00:00:00 2001
From: Dennis Whitney <DWhitney@travelclick.com>
Date: Tue, 4 Jan 2022 13:16:42 -0600
Subject: [PATCH] add directory exclusions

---
 README.md |  2 ++
 main.go   | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+)

diff --git a/README.md b/README.md
index 5de21fd..9e8680e 100644
--- a/README.md
+++ b/README.md
@@ -20,6 +20,8 @@ If you only want possibly vulnerable files to be printed rather than all files,
 Usage: log4shelldetect [options] <path>
 
 Options:
+  -exclude value
+        List of directories to exclude
   -include-zip
         include zip files in the scan
   -mode string
diff --git a/main.go b/main.go
index 139b769..3a14a2b 100644
--- a/main.go
+++ b/main.go
@@ -23,7 +23,22 @@ var printMutex = new(sync.Mutex)
 var mode = flag.String("mode", "report", "the output mode, either \"report\" (every java archive pretty printed) or \"list\" (list of potentially vulnerable files)")
 var includeZip = flag.Bool("include-zip", false, "include zip files in the scan")
 
+type exclusions []string
+
+func (i *exclusions) String() string {
+	return "my string representation"
+}
+
+func (i *exclusions) Set(value string) error {
+	*i = append(*i, value)
+	return nil
+}
+
+var excludedDirs exclusions
+
 func main() {
+	flag.Var(&excludedDirs, "exclude", "List of directories to exclude")
+
 	// Parse the arguments and flags provided to the program.
 	flag.Parse()
 
@@ -66,7 +81,13 @@ func main() {
 	// Scan through the directory provided recursively.
 	err = godirwalk.Walk(target, &godirwalk.Options{
 		Callback: func(osPathname string, de *godirwalk.Dirent) error {
+			// Check to see if we should be skipping this file due to any exclusions.
+			if shouldSkip(osPathname) {
+				return nil
+			}
+
 			// For each file in the directory, check if it ends in a known Java archive extension
+
 			if shouldCheck(osPathname) {
 				pool <- struct{}{}
 				// If it is, take a goroutine (thread) from the thread pool
@@ -116,6 +137,17 @@ func main() {
 	}
 }
 
+func shouldSkip(filename string) bool {
+	if len(excludedDirs) > 0 {
+		for _, eDir := range excludedDirs {
+			if strings.HasPrefix(strings.ToLower(filename), strings.ToLower(eDir)) {
+				return true
+			}
+		}
+	}
+	return false
+}
+
 func shouldCheck(filename string) bool {
 	ext := strings.ToLower(path.Ext(filename))
 	switch ext {