1 files changed, 25 insertions, 0 deletions
diff --git a/src/basic/util.c b/src/basic/util.c
index c63ec0ceb0..054d45092e 100644
--- a/src/basic/util.c
+++ b/src/basic/util.c
@@ -6842,3 +6842,28 @@ int version(void) {
              SYSTEMD_FEATURES);
         return 0;
 }
+
+bool fdname_is_valid(const char *s) {
+        const char *p;
+
+        /* Validates a name for $LISTEN_NAMES. We basically allow
+         * everything ASCII that's not a control character. Also, as
+         * special exception the ":" character is not allowed, as we
+         * use that as field separator in $LISTEN_NAMES.
+         *
+         * Note that the empty string is explicitly allowed here.*/
+
+        if (!s)
+                return false;
+
+        for (p = s; *p; p++) {
+                if (*p < ' ')
+                        return false;
+                if (*p >= 127)
+                        return false;
+                if (*p == ':')
+                        return false;
+        }
+
+        return p - s < 256;
+}