Only use the fallback mtu after 2 unsuccessful retransmissions if it is less

[openssl.git] / ssl / d1_lib.c

diff --git a/ssl/d1_lib.c b/ssl/d1_lib.c
index 6405111066e21e9474ef13ffd56ffb890b74f033..308afff2d4ef2fe62a0176ea19241794f0ede5cf 100644 (file)
--- a/ssl/d1_lib.c
+++ b/ssl/d1_lib.c
@@ -139,6 +139,9 @@ int dtls1_new(SSL *s)
                d1->cookie_len = sizeof(s->d1->cookie);
                }
 
+       d1->link_mtu = 0;
+       d1->mtu = 0;
+
        if( ! d1->unprocessed_rcds.q || ! d1->processed_rcds.q 
         || ! d1->buffered_messages || ! d1->sent_messages || ! d1->buffered_app_data.q)
                {
@@ -187,16 +190,14 @@ static void dtls1_clear_queues(SSL *s)
     while( (item = pqueue_pop(s->d1->buffered_messages)) != NULL)
         {
         frag = (hm_fragment *)item->data;
-        OPENSSL_free(frag->fragment);
-        OPENSSL_free(frag);
+        dtls1_hm_fragment_free(frag);
         pitem_free(item);
         }
 
     while ( (item = pqueue_pop(s->d1->sent_messages)) != NULL)
         {
         frag = (hm_fragment *)item->data;
-        OPENSSL_free(frag->fragment);
-        OPENSSL_free(frag);
+        dtls1_hm_fragment_free(frag);
         pitem_free(item);
         }
 
@@ -236,6 +237,7 @@ void dtls1_clear(SSL *s)
        pqueue sent_messages;
        pqueue buffered_app_data;
        unsigned int mtu;
+       unsigned int link_mtu;
 
        if (s->d1)
                {
@@ -245,6 +247,7 @@ void dtls1_clear(SSL *s)
                sent_messages = s->d1->sent_messages;
                buffered_app_data = s->d1->buffered_app_data.q;
                mtu = s->d1->mtu;
+               link_mtu = s->d1->link_mtu;
 
                dtls1_clear_queues(s);
 
@@ -258,6 +261,7 @@ void dtls1_clear(SSL *s)
                if (SSL_get_options(s) & SSL_OP_NO_QUERY_MTU)
                        {
                        s->d1->mtu = mtu;
+                       s->d1->link_mtu = link_mtu;
                        }
 
                s->d1->unprocessed_rcds.q = unprocessed_rcds;
@@ -294,7 +298,45 @@ long dtls1_ctrl(SSL *s, int cmd, long larg, void *parg)
        case DTLS_CTRL_LISTEN:
                ret = dtls1_listen(s, parg);
                break;
-
+       case SSL_CTRL_CHECK_PROTO_VERSION:
+               /* For library-internal use; checks that the current protocol
+                * is the highest enabled version (according to s->ctx->method,
+                * as version negotiation may have changed s->method). */
+               if (s->version == s->ctx->method->version)
+                       return 1;
+               /* Apparently we're using a version-flexible SSL_METHOD
+                * (not at its highest protocol version). */
+               if (s->ctx->method->version == DTLS_method()->version)
+                       {
+#if DTLS_MAX_VERSION != DTLS1_2_VERSION
+#  error Code needs update for DTLS_method() support beyond DTLS1_2_VERSION.
+#endif
+                       if (!(s->options & SSL_OP_NO_DTLSv1_2))
+                               return s->version == DTLS1_2_VERSION;
+                       if (!(s->options & SSL_OP_NO_DTLSv1))
+                               return s->version == DTLS1_VERSION;
+                       }
+               return 0; /* Unexpected state; fail closed. */
+
+               /* Just one protocol version is supported so far;
+                * fail closed if the version is not as expected. */
+               return s->version == DTLS_MAX_VERSION;
+       case DTLS_CTRL_SET_LINK_MTU:
+               if (larg < (long)dtls1_link_min_mtu())
+                       return 0;
+               s->d1->link_mtu = larg;
+               return 1;
+       case DTLS_CTRL_GET_LINK_MIN_MTU:
+               return (long)dtls1_link_min_mtu();
+       case SSL_CTRL_SET_MTU:
+               /*
+                *  We may not have a BIO set yet so can't call dtls1_min_mtu()
+                *  We'll have to make do with dtls1_link_min_mtu() and max overhead
+                */
+               if (larg < (long)dtls1_link_min_mtu() - DTLS1_MAX_MTU_OVERHEAD)
+                       return 0;
+               s->d1->mtu = larg;
+               return larg;
        default:
                ret = ssl3_ctrl(s, cmd, larg, parg);
                break;
@@ -433,12 +475,17 @@ void dtls1_stop_timer(SSL *s)
 
 int dtls1_check_timeout_num(SSL *s)
        {
+       unsigned int mtu;
+
        s->d1->timeout.num_alerts++;
 
        /* Reduce MTU after 2 unsuccessful retransmissions */
-       if (s->d1->timeout.num_alerts > 2)
+       if (s->d1->timeout.num_alerts > 2
+                       && !(SSL_get_options(s) & SSL_OP_NO_QUERY_MTU))
                {
-               s->d1->mtu = BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_GET_FALLBACK_MTU, 0, NULL);               
+               mtu = BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_GET_FALLBACK_MTU, 0, NULL);
+               if(mtu < s->d1->mtu)
+                       s->d1->mtu = mtu;
                }
 
        if (s->d1->timeout.num_alerts > DTLS1_TMO_ALERT_COUNT)