X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=blobdiff_plain;f=ssl%2Fd1_both.c;h=e6bc761e8bf236568c35da7f949c3dd9d77b4ccc;hp=5d26c949265ffd018155d85f77c88068eb86eacd;hb=e167fd05b8b781bf04fcd462c0d28fae386116fe;hpb=04d5242c46b0f348f5ab92e9764f138547b237c5

diff --git a/ssl/d1_both.c b/ssl/d1_both.c
index 5d26c94926..e6bc761e8b 100644
--- a/ssl/d1_both.c
+++ b/ssl/d1_both.c
@@ -517,6 +517,17 @@ long dtls1_get_message(SSL *s, int st1, int stn, int mt, long max, int *ok)
         return i;
     }
 
+    /*
+     * Don't change the *message* read sequence number while listening. For
+     * the *record* write sequence we reflect the ClientHello sequence number
+     * when listening.
+     */
+    if (s->d1->listen)
+        memcpy(s->s3->write_sequence, s->s3->read_sequence,
+               sizeof(s->s3->write_sequence));
+    else
+        s->d1->handshake_read_seq++;
+
     if (mt >= 0 && s->s3->tmp.message_type != mt) {
         al = SSL_AD_UNEXPECTED_MESSAGE;
         SSLerr(SSL_F_DTLS1_GET_MESSAGE, SSL_R_UNEXPECTED_MESSAGE);
@@ -544,10 +555,6 @@ long dtls1_get_message(SSL *s, int st1, int stn, int mt, long max, int *ok)
 
     memset(msg_hdr, 0x00, sizeof(struct hm_header_st));
 
-    /* Don't change sequence numbers while listening */
-    if (!s->d1->listen)
-        s->d1->handshake_read_seq++;
-
     s->init_msg = s->init_buf->data + DTLS1_HM_HEADER_LENGTH;
     return s->init_num;
 
@@ -581,9 +588,12 @@ static int dtls1_preprocess_fragment(SSL *s, struct hm_header_st *msg_hdr,
         /*
          * msg_len is limited to 2^24, but is effectively checked against max
          * above
+         *
+         * Make buffer slightly larger than message length as a precaution
+         * against small OOB reads e.g. CVE-2016-6306
          */
         if (!BUF_MEM_grow_clean
-            (s->init_buf, msg_len + DTLS1_HM_HEADER_LENGTH)) {
+            (s->init_buf, msg_len + DTLS1_HM_HEADER_LENGTH + 16)) {
             SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT, ERR_R_BUF_LIB);
             return SSL_AD_INTERNAL_ERROR;
         }
@@ -618,11 +628,23 @@ static int dtls1_retrieve_buffered_fragment(SSL *s, long max, int *ok)
     int al;
 
     *ok = 0;
-    item = pqueue_peek(s->d1->buffered_messages);
-    if (item == NULL)
-        return 0;
+    do {
+        item = pqueue_peek(s->d1->buffered_messages);
+        if (item == NULL)
+            return 0;
+
+        frag = (hm_fragment *)item->data;
+
+        if (frag->msg_header.seq < s->d1->handshake_read_seq) {
+            /* This is a stale message that has been buffered so clear it */
+            pqueue_pop(s->d1->buffered_messages);
+            dtls1_hm_fragment_free(frag);
+            pitem_free(item);
+            item = NULL;
+            frag = NULL;
+        }
+    } while (item == NULL);
 
-    frag = (hm_fragment *)item->data;
 
     /* Don't return if reassembly still in progress */
     if (frag->reassembly != NULL)
@@ -1053,7 +1075,9 @@ int dtls1_send_change_cipher_spec(SSL *s, int a, int b)
 int dtls1_read_failed(SSL *s, int code)
 {
     if (code > 0) {
+#ifdef TLS_DEBUG
         fprintf(stderr, "invalid state reached %s:%d", __FILE__, __LINE__);
+#endif
         return 1;
     }
 
@@ -1125,7 +1149,9 @@ int dtls1_retransmit_buffered_messages(SSL *s)
                                      (frag->msg_header.seq,
                                       frag->msg_header.is_ccs), 0,
                                      &found) <= 0 && found) {
+#ifdef TLS_DEBUG
             fprintf(stderr, "dtls1_retransmit_message() failed\n");
+#endif
             return -1;
         }
     }
@@ -1211,7 +1237,7 @@ dtls1_retransmit_message(SSL *s, unsigned short seq, unsigned long frag_off,
     unsigned long header_length;
     unsigned char seq64be[8];
     struct dtls1_retransmit_state saved_state;
-    unsigned char save_write_sequence[8];
+    unsigned char save_write_sequence[8] = {0, 0, 0, 0, 0, 0, 0, 0};
 
     /*-
       OPENSSL_assert(s->init_num == 0);
@@ -1225,7 +1251,9 @@ dtls1_retransmit_message(SSL *s, unsigned short seq, unsigned long frag_off,
 
     item = pqueue_find(s->d1->sent_messages, seq64be);
     if (item == NULL) {
+#ifdef TLS_DEBUG
         fprintf(stderr, "retransmit:  message %d non-existant\n", seq);
+#endif
         *found = 0;
         return 0;
     }
@@ -1296,18 +1324,6 @@ dtls1_retransmit_message(SSL *s, unsigned short seq, unsigned long frag_off,
     return ret;
 }
 
-/* call this function when the buffered messages are no longer needed */
-void dtls1_clear_record_buffer(SSL *s)
-{
-    pitem *item;
-
-    for (item = pqueue_pop(s->d1->sent_messages);
-         item != NULL; item = pqueue_pop(s->d1->sent_messages)) {
-        dtls1_hm_fragment_free((hm_fragment *)item->data);
-        pitem_free(item);
-    }
-}
-
 unsigned char *dtls1_set_message_header(SSL *s, unsigned char *p,
                                         unsigned char mt, unsigned long len,
                                         unsigned long frag_off,
@@ -1469,7 +1485,7 @@ int dtls1_process_heartbeat(SSL *s)
         memcpy(bp, pl, payload);
         bp += payload;
         /* Random padding */
-        if (RAND_pseudo_bytes(bp, padding) < 0) {
+        if (RAND_bytes(bp, padding) <= 0) {
             OPENSSL_free(buffer);
             return -1;
         }
@@ -1546,6 +1562,8 @@ int dtls1_heartbeat(SSL *s)
      *  - Padding
      */
     buf = OPENSSL_malloc(1 + 2 + payload + padding);
+    if (buf == NULL)
+        goto err;
     p = buf;
     /* Message Type */
     *p++ = TLS1_HB_REQUEST;
@@ -1554,11 +1572,11 @@ int dtls1_heartbeat(SSL *s)
     /* Sequence number */
     s2n(s->tlsext_hb_seq, p);
     /* 16 random bytes */
-    if (RAND_pseudo_bytes(p, 16) < 0)
+    if (RAND_bytes(p, 16) <= 0)
         goto err;
     p += 16;
     /* Random padding */
-    if (RAND_pseudo_bytes(p, padding) < 0)
+    if (RAND_bytes(p, padding) <= 0)
         goto err;
 
     ret = dtls1_write_bytes(s, TLS1_RT_HEARTBEAT, buf, 3 + payload + padding);