Fixed issue where a client might receive multiple push replies from

a server if it sent multiple push requests due to the server being
slow to respond.  This could cause the client to process pushed
options twice, leading to duplicate pushed routes, among other issues.
The fix, implemented server-side, is to reply only once to a push
request even if multiple requests are received.

git-svn-id: http://svn.openvpn.net/projects/openvpn/branches/BETA21/openvpn@7060 e7ae566f-a301-0410-adde-c780ea21d3b5

diff --git a/openvpn.h b/openvpn.h
index 0c4ff1acda17e090c28f11145a5efe57bb92f59f..47c9734b39133b11b342f28a3a562309c0f28f4e 100644 (file)
--- a/openvpn.h
+++ b/openvpn.h
@@ -414,6 +414,7 @@ struct context_2
   /* --ifconfig endpoints to be pushed to client */
   bool push_reply_deferred;
   bool push_ifconfig_defined;
+  bool sent_push_reply;
   in_addr_t push_ifconfig_local;
   in_addr_t push_ifconfig_remote_netmask;
 #ifdef ENABLE_CLIENT_NAT

diff --git a/push.c b/push.c
index 298031d10e252f0456778c171708ad2e69202460..f7b7d17b927830fb9139762c8031c706e35db2d2 100644 (file)
--- a/push.c
+++ b/push.c
@@ -331,8 +331,18 @@ process_incoming_push_msg (struct context *c,
        }
       else if (!c->c2.push_reply_deferred && c->c2.context_auth == CAS_SUCCEEDED)
        {
-         if (send_push_reply (c))
-           ret = PUSH_MSG_REQUEST;
+         if (c->c2.sent_push_reply)
+           {
+             ret = PUSH_MSG_ALREADY_REPLIED;
+           }
+         else
+           {
+             if (send_push_reply (c))
+               {
+                 ret = PUSH_MSG_REQUEST;
+                 c->c2.sent_push_reply = true;
+               }
+           }
        }
       else
        {

diff --git a/push.h b/push.h
index 089cf45b53f1fcfa52be43ce4615196a6da88056..b5d1fbf3d209fc71c91cdb57f7a0e4cc37a5de4b 100644 (file)
--- a/push.h
+++ b/push.h
@@ -35,6 +35,7 @@
 #define PUSH_MSG_REQUEST_DEFERRED 3
 #define PUSH_MSG_AUTH_FAILURE     4
 #define PUSH_MSG_CONTINUATION     5
+#define PUSH_MSG_ALREADY_REPLIED  6
 
 void incoming_push_message (struct context *c,
                            const struct buffer *buffer);