New upstream version 2.4.5upstream/2.4.5

1 files changed, 31 insertions, 7 deletions

diff --git a/src/openvpn/mroute.c b/src/openvpn/mroute.c
index 74ee360..28940a8 100644
--- a/src/openvpn/mroute.c
+++ b/src/openvpn/mroute.c
@@ -5,7 +5,7 @@
  *             packet encryption, packet authentication, and
  *             packet compression.
  *
- *  Copyright (C) 2002-2017 OpenVPN Technologies, Inc. <sales@openvpn.net>
+ *  Copyright (C) 2002-2018 OpenVPN Inc <sales@openvpn.net>
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License version 2
@@ -65,25 +65,49 @@ is_mac_mcast_maddr(const struct mroute_addr *addr)
  * Don't learn certain addresses.
  */
 bool
-mroute_learnable_address(const struct mroute_addr *addr)
+mroute_learnable_address(const struct mroute_addr *addr, struct gc_arena *gc)
 {
     int i;
-    bool not_all_zeros = false;
-    bool not_all_ones = false;
+    bool all_zeros = true;
+    bool all_ones = true;
 
     for (i = 0; i < addr->len; ++i)
     {
         int b = addr->raw_addr[i];
         if (b != 0x00)
         {
-            not_all_zeros = true;
+            all_zeros = false;
         }
         if (b != 0xFF)
         {
-            not_all_ones = true;
+            all_ones = false;
         }
     }
-    return not_all_zeros && not_all_ones && !is_mac_mcast_maddr(addr);
+
+    /* only networkss shorter than 8 bits are allowed to be all 0s. */
+    if (all_zeros
+        && !((addr->type & MR_WITH_NETBITS) && (addr->netbits < 8)))
+    {
+        msg(D_MULTI_LOW, "Can't learn %s: network is all 0s, but netbits >= 8",
+            mroute_addr_print(addr, gc));
+        return false;
+    }
+
+    if (all_ones)
+    {
+        msg(D_MULTI_LOW, "Can't learn %s: network is all 1s",
+            mroute_addr_print(addr, gc));
+        return false;
+    }
+
+    if (is_mac_mcast_maddr(addr))
+    {
+        msg(D_MULTI_LOW, "Can't learn %s: network is a multicast address",
+            mroute_addr_print(addr, gc));
+        return false;
+    }
+
+    return true;
 }
 
 static inline void