+
+int dtls1_shutdown(SSL *s)
+{
+ int ret;
+#ifndef OPENSSL_NO_SCTP
+ if (BIO_dgram_is_sctp(SSL_get_wbio(s)) &&
+ !(s->shutdown & SSL_SENT_SHUTDOWN)) {
+ ret = BIO_dgram_sctp_wait_for_dry(SSL_get_wbio(s));
+ if (ret < 0)
+ return -1;
+
+ if (ret == 0)
+ BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SAVE_SHUTDOWN, 1,
+ NULL);
+ }
+#endif
+ ret = ssl3_shutdown(s);
+#ifndef OPENSSL_NO_SCTP
+ BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SAVE_SHUTDOWN, 0, NULL);
+#endif
+ return ret;
+}
+
+#ifndef OPENSSL_NO_HEARTBEATS
+int dtls1_process_heartbeat(SSL *s)
+{
+ unsigned char *p = &s->s3->rrec.data[0], *pl;
+ unsigned short hbtype;
+ unsigned int payload;
+ unsigned int padding = 16; /* Use minimum padding */
+
+ if (s->msg_callback)
+ s->msg_callback(0, s->version, TLS1_RT_HEARTBEAT,
+ &s->s3->rrec.data[0], s->s3->rrec.length,
+ s, s->msg_callback_arg);
+
+ /* Read type and payload length first */
+ if (1 + 2 + 16 > s->s3->rrec.length)
+ return 0; /* silently discard */
+ if (s->s3->rrec.length > SSL3_RT_MAX_PLAIN_LENGTH)
+ return 0; /* silently discard per RFC 6520 sec. 4 */
+
+ hbtype = *p++;
+ n2s(p, payload);
+ if (1 + 2 + payload + 16 > s->s3->rrec.length)
+ return 0; /* silently discard per RFC 6520 sec. 4 */
+ pl = p;
+
+ if (hbtype == TLS1_HB_REQUEST) {
+ unsigned char *buffer, *bp;
+ unsigned int write_length = 1 /* heartbeat type */ +
+ 2 /* heartbeat length */ +
+ payload + padding;
+ int r;
+
+ if (write_length > SSL3_RT_MAX_PLAIN_LENGTH)
+ return 0;
+
+ /*
+ * Allocate memory for the response, size is 1 byte message type,
+ * plus 2 bytes payload length, plus payload, plus padding
+ */
+ buffer = OPENSSL_malloc(write_length);
+ if (buffer == NULL)
+ return -1;
+ bp = buffer;
+
+ /* Enter response type, length and copy payload */
+ *bp++ = TLS1_HB_RESPONSE;
+ s2n(payload, bp);
+ memcpy(bp, pl, payload);
+ bp += payload;
+ /* Random padding */
+ RAND_pseudo_bytes(bp, padding);
+
+ r = dtls1_write_bytes(s, TLS1_RT_HEARTBEAT, buffer, write_length);
+
+ if (r >= 0 && s->msg_callback)
+ s->msg_callback(1, s->version, TLS1_RT_HEARTBEAT,
+ buffer, write_length, s, s->msg_callback_arg);
+
+ OPENSSL_free(buffer);
+
+ if (r < 0)
+ return r;
+ } else if (hbtype == TLS1_HB_RESPONSE) {
+ unsigned int seq;
+
+ /*
+ * We only send sequence numbers (2 bytes unsigned int), and 16
+ * random bytes, so we just try to read the sequence number
+ */
+ n2s(pl, seq);
+
+ if (payload == 18 && seq == s->tlsext_hb_seq) {
+ dtls1_stop_timer(s);
+ s->tlsext_hb_seq++;
+ s->tlsext_hb_pending = 0;
+ }
+ }
+
+ return 0;
+}
+
+int dtls1_heartbeat(SSL *s)
+{
+ unsigned char *buf, *p;
+ int ret;
+ unsigned int payload = 18; /* Sequence number + random bytes */
+ unsigned int padding = 16; /* Use minimum padding */
+
+ /* Only send if peer supports and accepts HB requests... */
+ if (!(s->tlsext_heartbeat & SSL_TLSEXT_HB_ENABLED) ||
+ s->tlsext_heartbeat & SSL_TLSEXT_HB_DONT_SEND_REQUESTS) {
+ SSLerr(SSL_F_DTLS1_HEARTBEAT, SSL_R_TLS_HEARTBEAT_PEER_DOESNT_ACCEPT);
+ return -1;
+ }
+
+ /* ...and there is none in flight yet... */
+ if (s->tlsext_hb_pending) {
+ SSLerr(SSL_F_DTLS1_HEARTBEAT, SSL_R_TLS_HEARTBEAT_PENDING);
+ return -1;
+ }
+
+ /* ...and no handshake in progress. */
+ if (SSL_in_init(s) || s->in_handshake) {
+ SSLerr(SSL_F_DTLS1_HEARTBEAT, SSL_R_UNEXPECTED_MESSAGE);
+ return -1;
+ }
+
+ /*
+ * Check if padding is too long, payload and padding must not exceed 2^14
+ * - 3 = 16381 bytes in total.
+ */
+ OPENSSL_assert(payload + padding <= 16381);
+
+ /*-
+ * Create HeartBeat message, we just use a sequence number
+ * as payload to distuingish different messages and add
+ * some random stuff.
+ * - Message Type, 1 byte
+ * - Payload Length, 2 bytes (unsigned int)
+ * - Payload, the sequence number (2 bytes uint)
+ * - Payload, random bytes (16 bytes uint)
+ * - Padding
+ */
+ buf = OPENSSL_malloc(1 + 2 + payload + padding);
+ if (buf == NULL) {
+ SSLerr(SSL_F_DTLS1_HEARTBEAT, ERR_R_MALLOC_FAILURE);
+ return -1;
+ }
+ p = buf;
+ /* Message Type */
+ *p++ = TLS1_HB_REQUEST;
+ /* Payload length (18 bytes here) */
+ s2n(payload, p);
+ /* Sequence number */
+ s2n(s->tlsext_hb_seq, p);
+ /* 16 random bytes */
+ RAND_pseudo_bytes(p, 16);
+ p += 16;
+ /* Random padding */
+ RAND_pseudo_bytes(p, padding);
+
+ ret = dtls1_write_bytes(s, TLS1_RT_HEARTBEAT, buf, 3 + payload + padding);
+ if (ret >= 0) {
+ if (s->msg_callback)
+ s->msg_callback(1, s->version, TLS1_RT_HEARTBEAT,
+ buf, 3 + payload + padding,
+ s, s->msg_callback_arg);
+
+ dtls1_start_timer(s);
+ s->tlsext_hb_pending = 1;
+ }
+
+ OPENSSL_free(buf);
+
+ return ret;
+}
+#endif