firewalld: allow interface names containing '-'

Previously, interface names could only contain alphanumerics.

BUG=none
TEST=ran iptables unit tests

Change-Id: I19951389f7fef54f74568592f6988fd5da1b164b
Reviewed-on: https://chromium-review.googlesource.com/255152
Reviewed-by: Jorge Lucangeli Obes <jorgelo@chromium.org>
Tested-by: Aaron Kemp <kemp@google.com>
Commit-Queue: Aaron Kemp <kemp@google.com>

1 files changed, 8 insertions, 3 deletions

diff --git a/iptables.cc b/iptables.cc
index 43daf1b..73d373d 100644
--- a/iptables.cc
+++ b/iptables.cc
@@ -9,6 +9,7 @@
 
 #include <base/logging.h>
 #include <base/strings/string_number_conversions.h>
+#include <base/strings/string_util.h>
 #include <base/strings/stringprintf.h>
 #include <chromeos/process.h>
 
@@ -29,13 +30,17 @@ const char kMarkForUserTraffic[] = "1";
 const char kTableIdForUserTraffic[] = "1";
 
 bool IsValidInterfaceName(const std::string& iface) {
-  // |iface| should be shorter than |kInterfaceNameSize| chars,
-  // and have only alphanumeric characters.
+  // |iface| should be shorter than |kInterfaceNameSize| chars and have only
+  // alphanumeric characters (embedded hypens are also permitted).
   if (iface.length() >= kInterfaceNameSize) {
     return false;
   }
+  if (StartsWithASCII(iface, "-", true /* case_sensitive */) ||
+      EndsWith(iface, "-", true /* case_sensitive */)) {
+    return false;
+  }
   for (auto c : iface) {
-    if (!std::isalnum(c)) {
+    if (!std::isalnum(c) && (c != '-')) {
       return false;
     }
   }