Refactor dtls1_clear_queues()

An upcoming cleanup diff by jsing needs dtls1_clear_queues() to be
able to handle NULL pqueues. While one can easily add a NULL check
to pqueue_pop(), this does not really fit in with the rest of the
code. There are two kinds of while loops in dtls1_clear_queues that
drain pqueues, so add two helper functions with a NULL check each.

ok jsing

1 files changed, 26 insertions, 25 deletions

diff --git a/src/lib/libssl/d1_lib.c b/src/lib/libssl/d1_lib.c
index 758f5195e6..a728944047 100644
--- a/src/lib/libssl/d1_lib.c
+++ b/src/lib/libssl/d1_lib.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: d1_lib.c,v 1.47 2020/09/24 17:59:54 jsing Exp $ */
+/* $OpenBSD: d1_lib.c,v 1.48 2020/09/26 07:36:51 tb Exp $ */
 /*
  * DTLS implementation written by Nagendra Modadugu
  * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
@@ -124,46 +124,47 @@ dtls1_new(SSL *s)
 }
 
 static void
-dtls1_clear_queues(SSL *s)
+dtls1_drain_records(pqueue queue)
 {
-        pitem *item = NULL;
-        hm_fragment *frag = NULL;
+        pitem *item;
         DTLS1_RECORD_DATA_INTERNAL *rdata;
 
-        while ((item = pqueue_pop(D1I(s)->unprocessed_rcds.q)) != NULL) {
-                rdata = (DTLS1_RECORD_DATA_INTERNAL *) item->data;
-                ssl3_release_buffer(&rdata->rbuf);
-                free(item->data);
-                pitem_free(item);
-        }
+        if (queue == NULL)
+                return;
 
-        while ((item = pqueue_pop(D1I(s)->processed_rcds.q)) != NULL) {
-                rdata = (DTLS1_RECORD_DATA_INTERNAL *) item->data;
+        while ((item = pqueue_pop(queue)) != NULL) {
+                rdata = (DTLS1_RECORD_DATA_INTERNAL *)item->data;
                 ssl3_release_buffer(&rdata->rbuf);
                 free(item->data);
                 pitem_free(item);
         }
+}
 
-        while ((item = pqueue_pop(D1I(s)->buffered_messages)) != NULL) {
-                frag = (hm_fragment *)item->data;
-                free(frag->fragment);
-                free(frag);
-                pitem_free(item);
-        }
+static void
+dtls1_drain_fragments(pqueue queue)
+{
+        pitem *item;
+        hm_fragment *frag;
+
+        if (queue == NULL)
+                return;
 
-        while ((item = pqueue_pop(s->d1->sent_messages)) != NULL) {
+        while ((item = pqueue_pop(queue)) != NULL) {
                 frag = (hm_fragment *)item->data;
                 free(frag->fragment);
                 free(frag);
                 pitem_free(item);
         }
+}
 
-        while ((item = pqueue_pop(D1I(s)->buffered_app_data.q)) != NULL) {
-                rdata = (DTLS1_RECORD_DATA_INTERNAL *) item->data;
-                ssl3_release_buffer(&rdata->rbuf);
-                free(item->data);
-                pitem_free(item);
-        }
+static void
+dtls1_clear_queues(SSL *s)
+{
+        dtls1_drain_records(D1I(s)->unprocessed_rcds.q);
+        dtls1_drain_records(D1I(s)->processed_rcds.q);
+        dtls1_drain_fragments(D1I(s)->buffered_messages);
+        dtls1_drain_fragments(s->d1->sent_messages);
+        dtls1_drain_records(D1I(s)->buffered_app_data.q);
 }
 
 void