[openssl.org #2506] [PATCH] SSL_clear not fully implemented for DTLS

[Robin Seggelmann via RT]

The implementation of dtls1_clear(), called by SSL_clear(), is not handling the 
DTLS1_STATE struct at s->d1. Hence, calling SSL_clear() does not reset any 
value stored in this struct, which includes epochs, sequence numbers, replay 
check bitmask, buffered messages, etc. This also prevents the -reconnect option 
for s_client from working, because the state is not fully cleared and thus the 
next connection attempt starts with an initial ClientHello with epoch 1, which 
is invalid and ignored by the server. This patch adds clearing all values and 
emptying all queues in s->d1 when calling SSL_clear().

Best regards
Robin


--- ssl/d1_lib.c        3 Apr 2011 17:14:48 -0000       1.8.2.13.2.1
+++ ssl/d1_lib.c        27 Apr 2011 12:25:10 -0000
@@ -129,26 +129,22 @@
        return(1);
        }
 
-void dtls1_free(SSL *s)
+static void dtls1_clear_queues(SSL *s)
        {
     pitem *item = NULL;
     hm_fragment *frag = NULL;
-
-       ssl3_free(s);
-
+       
     while( (item = pqueue_pop(s->d1->unprocessed_rcds.q)) != NULL)
         {
         OPENSSL_free(item->data);
         pitem_free(item);
         }
-    pqueue_free(s->d1->unprocessed_rcds.q);
 
     while( (item = pqueue_pop(s->d1->processed_rcds.q)) != NULL)
         {
         OPENSSL_free(item->data);
         pitem_free(item);
         }
-    pqueue_free(s->d1->processed_rcds.q);
 
     while( (item = pqueue_pop(s->d1->buffered_messages)) != NULL)
         {
@@ -157,7 +153,6 @@
         OPENSSL_free(frag);
         pitem_free(item);
         }
-    pqueue_free(s->d1->buffered_messages);
 
     while ( (item = pqueue_pop(s->d1->sent_messages)) != NULL)
         {
@@ -166,7 +161,6 @@
         OPENSSL_free(frag);
         pitem_free(item);
         }
-       pqueue_free(s->d1->sent_messages);
 
        while ( (item = pqueue_pop(s->d1->buffered_app_data.q)) != NULL)
                {
@@ -175,6 +169,18 @@
                OPENSSL_free(frag);
                pitem_free(item);
                }
+       }
+
+void dtls1_free(SSL *s)
+       {
+       ssl3_free(s);
+
+       dtls1_clear_queues(s);
+
+    pqueue_free(s->d1->unprocessed_rcds.q);
+    pqueue_free(s->d1->processed_rcds.q);
+    pqueue_free(s->d1->buffered_messages);
+       pqueue_free(s->d1->sent_messages);
        pqueue_free(s->d1->buffered_app_data.q);
 
        OPENSSL_free(s->d1);
@@ -182,6 +188,36 @@
 
 void dtls1_clear(SSL *s)
        {
+    pqueue unprocessed_rcds;
+    pqueue processed_rcds;
+    pqueue buffered_messages;
+       pqueue sent_messages;
+       pqueue buffered_app_data;
+       
+       if (s->d1)
+               {
+               unprocessed_rcds = s->d1->unprocessed_rcds.q;
+               processed_rcds = s->d1->processed_rcds.q;
+               buffered_messages = s->d1->buffered_messages;
+               sent_messages = s->d1->sent_messages;
+               buffered_app_data = s->d1->buffered_app_data.q;
+
+               dtls1_clear_queues(s);
+
+               memset(s->d1, 0, sizeof(*(s->d1)));
+
+               if (s->server)
+                       {
+                       s->d1->cookie_len = sizeof(s->d1->cookie);
+                       }
+
+               s->d1->unprocessed_rcds.q = unprocessed_rcds;
+               s->d1->processed_rcds.q = processed_rcds;
+               s->d1->buffered_messages = buffered_messages;
+               s->d1->sent_messages = sent_messages;
+               s->d1->buffered_app_data.q = buffered_app_data;
+               }
+
        ssl3_clear(s);
        if (s->options & SSL_OP_CISCO_ANYCONNECT)
                s->version=DTLS1_BAD_VER;

dtls-clear-1.0.1.patch
Description: Binary data

dtls-clear-1.0.0.patch
Description: Binary data

dtls-clear-0.9.8.patch
Description: Binary data