/* ssl/d1_lib.c */
-/*
+/*
* DTLS implementation written by Nagendra Modadugu
- * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
+ * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
*/
/* ====================================================================
* Copyright (c) 1999-2005 The OpenSSL Project. All rights reserved.
* are met:
*
* 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
+ * notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
#include <stdio.h>
#define USE_SOCKETS
#include <openssl/objects.h>
+#include <openssl/rand.h>
#include "ssl_locl.h"
-#if defined(OPENSSL_SYS_WIN32) || defined(OPENSSL_SYS_VMS)
-#include <sys/timeb.h>
+#if defined(OPENSSL_SYS_VMS)
+# include <sys/timeb.h>
+#elif defined(OPENSSL_SYS_NETWARE) && !defined(_WINSOCK2API_)
+# include <sys/timeval.h>
+#elif defined(OPENSSL_SYS_VXWORKS)
+# include <sys/times.h>
+#elif !defined(OPENSSL_SYS_WIN32)
+# include <sys/time.h>
#endif
static void get_current_time(struct timeval *t);
-const char dtls1_version_str[]="DTLSv1" OPENSSL_VERSION_PTEXT;
+static int dtls1_set_handshake_header(SSL *s, int type, unsigned long len);
+static int dtls1_handshake_write(SSL *s);
int dtls1_listen(SSL *s, struct sockaddr *client);
+static unsigned int dtls1_link_min_mtu(void);
+
+/* XDTLS: figure out the right values */
+static const unsigned int g_probable_mtu[] = { 1500, 512, 256 };
-SSL3_ENC_METHOD DTLSv1_enc_data={
- dtls1_enc,
- tls1_mac,
- tls1_setup_key_block,
- tls1_generate_master_secret,
- tls1_change_cipher_state,
- tls1_final_finish_mac,
- TLS1_FINISH_MAC_LENGTH,
- tls1_cert_verify_mac,
- TLS_MD_CLIENT_FINISH_CONST,TLS_MD_CLIENT_FINISH_CONST_SIZE,
- TLS_MD_SERVER_FINISH_CONST,TLS_MD_SERVER_FINISH_CONST_SIZE,
- tls1_alert_code,
- };
+const SSL3_ENC_METHOD DTLSv1_enc_data = {
+ tls1_enc,
+ tls1_mac,
+ tls1_setup_key_block,
+ tls1_generate_master_secret,
+ tls1_change_cipher_state,
+ tls1_final_finish_mac,
+ TLS1_FINISH_MAC_LENGTH,
+ tls1_cert_verify_mac,
+ TLS_MD_CLIENT_FINISH_CONST, TLS_MD_CLIENT_FINISH_CONST_SIZE,
+ TLS_MD_SERVER_FINISH_CONST, TLS_MD_SERVER_FINISH_CONST_SIZE,
+ tls1_alert_code,
+ tls1_export_keying_material,
+ SSL_ENC_FLAG_DTLS | SSL_ENC_FLAG_EXPLICIT_IV,
+ DTLS1_HM_HEADER_LENGTH,
+ dtls1_set_handshake_header,
+ dtls1_handshake_write
+};
+
+const SSL3_ENC_METHOD DTLSv1_2_enc_data = {
+ tls1_enc,
+ tls1_mac,
+ tls1_setup_key_block,
+ tls1_generate_master_secret,
+ tls1_change_cipher_state,
+ tls1_final_finish_mac,
+ TLS1_FINISH_MAC_LENGTH,
+ tls1_cert_verify_mac,
+ TLS_MD_CLIENT_FINISH_CONST, TLS_MD_CLIENT_FINISH_CONST_SIZE,
+ TLS_MD_SERVER_FINISH_CONST, TLS_MD_SERVER_FINISH_CONST_SIZE,
+ tls1_alert_code,
+ tls1_export_keying_material,
+ SSL_ENC_FLAG_DTLS | SSL_ENC_FLAG_EXPLICIT_IV | SSL_ENC_FLAG_SIGALGS
+ | SSL_ENC_FLAG_SHA256_PRF | SSL_ENC_FLAG_TLS1_2_CIPHERS,
+ DTLS1_HM_HEADER_LENGTH,
+ dtls1_set_handshake_header,
+ dtls1_handshake_write
+};
long dtls1_default_timeout(void)
- {
- /* 2 hours, the 24 hours mentioned in the DTLSv1 spec
- * is way too long for http, the cache would over fill */
- return(60*60*2);
- }
+{
+ /*
+ * 2 hours, the 24 hours mentioned in the DTLSv1 spec is way too long for
+ * http, the cache would over fill
+ */
+ return (60 * 60 * 2);
+}
int dtls1_new(SSL *s)
- {
- DTLS1_STATE *d1;
-
- if (!ssl3_new(s)) return(0);
- if ((d1=OPENSSL_malloc(sizeof *d1)) == NULL) return (0);
- memset(d1,0, sizeof *d1);
-
- /* d1->handshake_epoch=0; */
-
- d1->unprocessed_rcds.q=pqueue_new();
- d1->processed_rcds.q=pqueue_new();
- d1->buffered_messages = pqueue_new();
- d1->sent_messages=pqueue_new();
- d1->buffered_app_data.q=pqueue_new();
-
- if ( s->server)
- {
- d1->cookie_len = sizeof(s->d1->cookie);
- }
-
- if( ! d1->unprocessed_rcds.q || ! d1->processed_rcds.q
- || ! d1->buffered_messages || ! d1->sent_messages || ! d1->buffered_app_data.q)
- {
- if ( d1->unprocessed_rcds.q) pqueue_free(d1->unprocessed_rcds.q);
- if ( d1->processed_rcds.q) pqueue_free(d1->processed_rcds.q);
- if ( d1->buffered_messages) pqueue_free(d1->buffered_messages);
- if ( d1->sent_messages) pqueue_free(d1->sent_messages);
- if ( d1->buffered_app_data.q) pqueue_free(d1->buffered_app_data.q);
- OPENSSL_free(d1);
- return (0);
- }
-
- s->d1=d1;
- s->method->ssl_clear(s);
- return(1);
- }
+{
+ DTLS1_STATE *d1;
+
+ if (!DTLS_RECORD_LAYER_new(&s->rlayer)) {
+ return 0;
+ }
+
+ if (!ssl3_new(s))
+ return (0);
+ if ((d1 = OPENSSL_zalloc(sizeof(*d1))) == NULL) {
+ ssl3_free(s);
+ return (0);
+ }
+
+ d1->buffered_messages = pqueue_new();
+ d1->sent_messages = pqueue_new();
+
+ if (s->server) {
+ d1->cookie_len = sizeof(s->d1->cookie);
+ }
+
+ d1->link_mtu = 0;
+ d1->mtu = 0;
+
+ if (d1->buffered_messages == NULL || d1->sent_messages == NULL) {
+ pqueue_free(d1->buffered_messages);
+ pqueue_free(d1->sent_messages);
+ OPENSSL_free(d1);
+ ssl3_free(s);
+ return (0);
+ }
+
+ s->d1 = d1;
+ s->method->ssl_clear(s);
+ return (1);
+}
static void dtls1_clear_queues(SSL *s)
- {
+{
pitem *item = NULL;
hm_fragment *frag = NULL;
- DTLS1_RECORD_DATA *rdata;
-
- while( (item = pqueue_pop(s->d1->unprocessed_rcds.q)) != NULL)
- {
- rdata = (DTLS1_RECORD_DATA *) item->data;
- if (rdata->rbuf.buf)
- {
- OPENSSL_free(rdata->rbuf.buf);
- }
- OPENSSL_free(item->data);
- pitem_free(item);
- }
- while( (item = pqueue_pop(s->d1->processed_rcds.q)) != NULL)
- {
- rdata = (DTLS1_RECORD_DATA *) item->data;
- if (rdata->rbuf.buf)
- {
- OPENSSL_free(rdata->rbuf.buf);
- }
- OPENSSL_free(item->data);
- pitem_free(item);
- }
-
- while( (item = pqueue_pop(s->d1->buffered_messages)) != NULL)
- {
+ 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)
- {
+ 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);
- }
-
- while ( (item = pqueue_pop(s->d1->buffered_app_data.q)) != NULL)
- {
- frag = (hm_fragment *)item->data;
- OPENSSL_free(frag->fragment);
- OPENSSL_free(frag);
- pitem_free(item);
- }
- }
+ }
+}
void dtls1_free(SSL *s)
- {
- ssl3_free(s);
+{
+ DTLS_RECORD_LAYER_free(&s->rlayer);
+
+ ssl3_free(s);
- dtls1_clear_queues(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);
+ pqueue_free(s->d1->sent_messages);
- OPENSSL_free(s->d1);
- }
+ OPENSSL_free(s->d1);
+ s->d1 = NULL;
+}
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;
- else
- s->version=DTLS1_VERSION;
- }
+ pqueue sent_messages;
+ unsigned int mtu;
+ unsigned int link_mtu;
+
+ DTLS_RECORD_LAYER_clear(&s->rlayer);
+
+ if (s->d1) {
+ buffered_messages = s->d1->buffered_messages;
+ sent_messages = s->d1->sent_messages;
+ mtu = s->d1->mtu;
+ link_mtu = s->d1->link_mtu;
+
+ dtls1_clear_queues(s);
+
+ memset(s->d1, 0, sizeof(*s->d1));
+
+ if (s->server) {
+ s->d1->cookie_len = sizeof(s->d1->cookie);
+ }
+
+ if (SSL_get_options(s) & SSL_OP_NO_QUERY_MTU) {
+ s->d1->mtu = mtu;
+ s->d1->link_mtu = link_mtu;
+ }
+
+ s->d1->buffered_messages = buffered_messages;
+ s->d1->sent_messages = sent_messages;
+ }
+
+ ssl3_clear(s);
+ if (s->options & SSL_OP_CISCO_ANYCONNECT)
+ s->client_version = s->version = DTLS1_BAD_VER;
+ else if (s->method->version == DTLS_ANY_VERSION)
+ s->version = DTLS1_2_VERSION;
+ else
+ s->version = s->method->version;
+}
long dtls1_ctrl(SSL *s, int cmd, long larg, void *parg)
- {
- int ret=0;
-
- switch (cmd)
- {
- case DTLS_CTRL_GET_TIMEOUT:
- if (dtls1_get_timeout(s, (struct timeval*) parg) != NULL)
- {
- ret = 1;
- }
- break;
- case DTLS_CTRL_HANDLE_TIMEOUT:
- ret = dtls1_handle_timeout(s);
- break;
- case DTLS_CTRL_LISTEN:
- ret = dtls1_listen(s, parg);
- break;
-
- default:
- ret = ssl3_ctrl(s, cmd, larg, parg);
- break;
- }
- return(ret);
- }
+{
+ int ret = 0;
+
+ switch (cmd) {
+ case DTLS_CTRL_GET_TIMEOUT:
+ if (dtls1_get_timeout(s, (struct timeval *)parg) != NULL) {
+ ret = 1;
+ }
+ break;
+ case DTLS_CTRL_HANDLE_TIMEOUT:
+ ret = dtls1_handle_timeout(s);
+ break;
+ 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. */
+ 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;
+ }
+ return (ret);
+}
/*
* As it's impossible to use stream ciphers in "datagram" mode, this
* available, but if new ones emerge, they will have to be added...
*/
const SSL_CIPHER *dtls1_get_cipher(unsigned int u)
- {
- const SSL_CIPHER *ciph = ssl3_get_cipher(u);
+{
+ const SSL_CIPHER *ciph = ssl3_get_cipher(u);
- if (ciph != NULL)
- {
- if (ciph->algorithm_enc == SSL_RC4)
- return NULL;
- }
+ if (ciph != NULL) {
+ if (ciph->algorithm_enc == SSL_RC4)
+ return NULL;
+ }
- return ciph;
- }
+ return ciph;
+}
void dtls1_start_timer(SSL *s)
- {
- /* If timer is not set, initialize duration with 1 second */
- if (s->d1->next_timeout.tv_sec == 0 && s->d1->next_timeout.tv_usec == 0)
- {
- s->d1->timeout_duration = 1;
- }
-
- /* Set timeout to current time */
- get_current_time(&(s->d1->next_timeout));
-
- /* Add duration to current time */
- s->d1->next_timeout.tv_sec += s->d1->timeout_duration;
- BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT, 0, &(s->d1->next_timeout));
- }
-
-struct timeval* dtls1_get_timeout(SSL *s, struct timeval* timeleft)
- {
- struct timeval timenow;
-
- /* If no timeout is set, just return NULL */
- if (s->d1->next_timeout.tv_sec == 0 && s->d1->next_timeout.tv_usec == 0)
- {
- return NULL;
- }
-
- /* Get current time */
- get_current_time(&timenow);
-
- /* If timer already expired, set remaining time to 0 */
- if (s->d1->next_timeout.tv_sec < timenow.tv_sec ||
- (s->d1->next_timeout.tv_sec == timenow.tv_sec &&
- s->d1->next_timeout.tv_usec <= timenow.tv_usec))
- {
- memset(timeleft, 0, sizeof(struct timeval));
- return timeleft;
- }
-
- /* Calculate time left until timer expires */
- memcpy(timeleft, &(s->d1->next_timeout), sizeof(struct timeval));
- timeleft->tv_sec -= timenow.tv_sec;
- timeleft->tv_usec -= timenow.tv_usec;
- if (timeleft->tv_usec < 0)
- {
- timeleft->tv_sec--;
- timeleft->tv_usec += 1000000;
- }
-
- /* If remaining time is less than 15 ms, set it to 0
- * to prevent issues because of small devergences with
- * socket timeouts.
- */
- if (timeleft->tv_sec == 0 && timeleft->tv_usec < 15000)
- {
- memset(timeleft, 0, sizeof(struct timeval));
- }
-
-
- return timeleft;
- }
+{
+#ifndef OPENSSL_NO_SCTP
+ /* Disable timer for SCTP */
+ if (BIO_dgram_is_sctp(SSL_get_wbio(s))) {
+ memset(&s->d1->next_timeout, 0, sizeof(s->d1->next_timeout));
+ return;
+ }
+#endif
+
+ /* If timer is not set, initialize duration with 1 second */
+ if (s->d1->next_timeout.tv_sec == 0 && s->d1->next_timeout.tv_usec == 0) {
+ s->d1->timeout_duration = 1;
+ }
+
+ /* Set timeout to current time */
+ get_current_time(&(s->d1->next_timeout));
+
+ /* Add duration to current time */
+ s->d1->next_timeout.tv_sec += s->d1->timeout_duration;
+ BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT, 0,
+ &(s->d1->next_timeout));
+}
+
+struct timeval *dtls1_get_timeout(SSL *s, struct timeval *timeleft)
+{
+ struct timeval timenow;
+
+ /* If no timeout is set, just return NULL */
+ if (s->d1->next_timeout.tv_sec == 0 && s->d1->next_timeout.tv_usec == 0) {
+ return NULL;
+ }
+
+ /* Get current time */
+ get_current_time(&timenow);
+
+ /* If timer already expired, set remaining time to 0 */
+ if (s->d1->next_timeout.tv_sec < timenow.tv_sec ||
+ (s->d1->next_timeout.tv_sec == timenow.tv_sec &&
+ s->d1->next_timeout.tv_usec <= timenow.tv_usec)) {
+ memset(timeleft, 0, sizeof(*timeleft));
+ return timeleft;
+ }
+
+ /* Calculate time left until timer expires */
+ memcpy(timeleft, &(s->d1->next_timeout), sizeof(struct timeval));
+ timeleft->tv_sec -= timenow.tv_sec;
+ timeleft->tv_usec -= timenow.tv_usec;
+ if (timeleft->tv_usec < 0) {
+ timeleft->tv_sec--;
+ timeleft->tv_usec += 1000000;
+ }
+
+ /*
+ * If remaining time is less than 15 ms, set it to 0 to prevent issues
+ * because of small devergences with socket timeouts.
+ */
+ if (timeleft->tv_sec == 0 && timeleft->tv_usec < 15000) {
+ memset(timeleft, 0, sizeof(*timeleft));
+ }
+
+ return timeleft;
+}
int dtls1_is_timer_expired(SSL *s)
- {
- struct timeval timeleft;
+{
+ struct timeval timeleft;
- /* Get time left until timeout, return false if no timer running */
- if (dtls1_get_timeout(s, &timeleft) == NULL)
- {
- return 0;
- }
+ /* Get time left until timeout, return false if no timer running */
+ if (dtls1_get_timeout(s, &timeleft) == NULL) {
+ return 0;
+ }
- /* Return false if timer is not expired yet */
- if (timeleft.tv_sec > 0 || timeleft.tv_usec > 0)
- {
- return 0;
- }
+ /* Return false if timer is not expired yet */
+ if (timeleft.tv_sec > 0 || timeleft.tv_usec > 0) {
+ return 0;
+ }
- /* Timer expired, so return true */
- return 1;
- }
+ /* Timer expired, so return true */
+ return 1;
+}
void dtls1_double_timeout(SSL *s)
- {
- s->d1->timeout_duration *= 2;
- if (s->d1->timeout_duration > 60)
- s->d1->timeout_duration = 60;
- dtls1_start_timer(s);
- }
+{
+ s->d1->timeout_duration *= 2;
+ if (s->d1->timeout_duration > 60)
+ s->d1->timeout_duration = 60;
+ dtls1_start_timer(s);
+}
void dtls1_stop_timer(SSL *s)
- {
- /* Reset everything */
- memset(&(s->d1->next_timeout), 0, sizeof(struct timeval));
- s->d1->timeout_duration = 1;
- BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT, 0, &(s->d1->next_timeout));
- /* Clear retransmission buffer */
- dtls1_clear_record_buffer(s);
- }
+{
+ /* Reset everything */
+ memset(&s->d1->timeout, 0, sizeof(s->d1->timeout));
+ memset(&s->d1->next_timeout, 0, sizeof(s->d1->next_timeout));
+ s->d1->timeout_duration = 1;
+ BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT, 0,
+ &(s->d1->next_timeout));
+ /* Clear retransmission buffer */
+ dtls1_clear_record_buffer(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
+ && !(SSL_get_options(s) & SSL_OP_NO_QUERY_MTU)) {
+ 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) {
+ /* fail the connection, enough alerts have been sent */
+ SSLerr(SSL_F_DTLS1_CHECK_TIMEOUT_NUM, SSL_R_READ_TIMEOUT_EXPIRED);
+ return -1;
+ }
+
+ return 0;
+}
int dtls1_handle_timeout(SSL *s)
- {
- DTLS1_STATE *state;
-
- /* if no timer is expired, don't do anything */
- if (!dtls1_is_timer_expired(s))
- {
- return 0;
- }
-
- dtls1_double_timeout(s);
- state = s->d1;
- state->timeout.num_alerts++;
- if ( state->timeout.num_alerts > DTLS1_TMO_ALERT_COUNT)
- {
- /* fail the connection, enough alerts have been sent */
- SSLerr(SSL_F_DTLS1_HANDLE_TIMEOUT,SSL_R_READ_TIMEOUT_EXPIRED);
- return -1;
- }
-
- state->timeout.read_timeouts++;
- if ( state->timeout.read_timeouts > DTLS1_TMO_READ_COUNT)
- {
- state->timeout.read_timeouts = 1;
- }
-
- dtls1_start_timer(s);
- return dtls1_retransmit_buffered_messages(s);
- }
+{
+ /* if no timer is expired, don't do anything */
+ if (!dtls1_is_timer_expired(s)) {
+ return 0;
+ }
+
+ dtls1_double_timeout(s);
+
+ if (dtls1_check_timeout_num(s) < 0)
+ return -1;
+
+ s->d1->timeout.read_timeouts++;
+ if (s->d1->timeout.read_timeouts > DTLS1_TMO_READ_COUNT) {
+ s->d1->timeout.read_timeouts = 1;
+ }
+#ifndef OPENSSL_NO_HEARTBEATS
+ if (s->tlsext_hb_pending) {
+ s->tlsext_hb_pending = 0;
+ return dtls1_heartbeat(s);
+ }
+#endif
+
+ dtls1_start_timer(s);
+ return dtls1_retransmit_buffered_messages(s);
+}
static void get_current_time(struct timeval *t)
{
-#ifdef OPENSSL_SYS_WIN32
- struct _timeb tb;
- _ftime(&tb);
- t->tv_sec = (long)tb.time;
- t->tv_usec = (long)tb.millitm * 1000;
+#if defined(_WIN32)
+ SYSTEMTIME st;
+ union {
+ unsigned __int64 ul;
+ FILETIME ft;
+ } now;
+
+ GetSystemTime(&st);
+ SystemTimeToFileTime(&st, &now.ft);
+# ifdef __MINGW32__
+ now.ul -= 116444736000000000ULL;
+# else
+ now.ul -= 116444736000000000UI64; /* re-bias to 1/1/1970 */
+# endif
+ t->tv_sec = (long)(now.ul / 10000000);
+ t->tv_usec = ((int)(now.ul % 10000000)) / 10;
#elif defined(OPENSSL_SYS_VMS)
- struct timeb tb;
- ftime(&tb);
- t->tv_sec = (long)tb.time;
- t->tv_usec = (long)tb.millitm * 1000;
+ struct timeb tb;
+ ftime(&tb);
+ t->tv_sec = (long)tb.time;
+ t->tv_usec = (long)tb.millitm * 1000;
#else
- gettimeofday(t, NULL);
+ gettimeofday(t, NULL);
#endif
}
+
+#define LISTEN_SUCCESS 2
+#define LISTEN_SEND_VERIFY_REQUEST 1
+
+
int dtls1_listen(SSL *s, struct sockaddr *client)
- {
- int ret;
-
- SSL_set_options(s, SSL_OP_COOKIE_EXCHANGE);
- s->d1->listen = 1;
-
- ret = SSL_accept(s);
- if (ret <= 0) return ret;
-
- (void) BIO_dgram_get_peer(SSL_get_rbio(s), client);
- return 1;
- }
+{
+ int next, n, ret = 0, clearpkt = 0;
+ unsigned char cookie[DTLS1_COOKIE_LENGTH];
+ unsigned char seq[SEQ_NUM_SIZE];
+ unsigned char *data, *p, *buf;
+ unsigned long reclen, fragoff, fraglen, msglen;
+ unsigned int rectype, versmajor, msgseq, msgtype, clientvers, cookielen;
+ BIO *rbio, *wbio;
+ BUF_MEM *bufm;
+ struct sockaddr_storage tmpclient;
+ PACKET pkt, msgpkt, msgpayload, session, cookiepkt;
+
+ /* Ensure there is no state left over from a previous invocation */
+ if (!SSL_clear(s))
+ return -1;
+
+ ERR_clear_error();
+
+ rbio = SSL_get_rbio(s);
+ wbio = SSL_get_wbio(s);
+
+ if(!rbio || !wbio) {
+ SSLerr(SSL_F_DTLS1_LISTEN, SSL_R_BIO_NOT_SET);
+ return -1;
+ }
+
+ /*
+ * We only peek at incoming ClientHello's until we're sure we are going to
+ * to respond with a HelloVerifyRequest. If its a ClientHello with a valid
+ * cookie then we leave it in the BIO for dtls1_accept to handle.
+ */
+ BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_PEEK_MODE, 1, NULL);
+
+ /*
+ * Note: This check deliberately excludes DTLS1_BAD_VER because that version
+ * requires the MAC to be calculated *including* the first ClientHello
+ * (without the cookie). Since DTLSv1_listen is stateless that cannot be
+ * supported. DTLS1_BAD_VER must use cookies in a stateful manner (e.g. via
+ * SSL_accept)
+ */
+ if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00)) {
+ SSLerr(SSL_F_DTLS1_LISTEN, SSL_R_UNSUPPORTED_SSL_VERSION);
+ return -1;
+ }
+
+ if (s->init_buf == NULL) {
+ if ((bufm = BUF_MEM_new()) == NULL) {
+ SSLerr(SSL_F_DTLS1_LISTEN, ERR_R_MALLOC_FAILURE);
+ return -1;
+ }
+
+ if (!BUF_MEM_grow(bufm, SSL3_RT_MAX_PLAIN_LENGTH)) {
+ BUF_MEM_free(bufm);
+ SSLerr(SSL_F_DTLS1_LISTEN, ERR_R_MALLOC_FAILURE);
+ return -1;
+ }
+ s->init_buf = bufm;
+ }
+ buf = (unsigned char *)s->init_buf->data;
+
+ do {
+ /* Get a packet */
+
+ clear_sys_error();
+ /*
+ * Technically a ClientHello could be SSL3_RT_MAX_PLAIN_LENGTH
+ * + DTLS1_RT_HEADER_LENGTH bytes long. Normally init_buf does not store
+ * the record header as well, but we do here. We've set up init_buf to
+ * be the standard size for simplicity. In practice we shouldn't ever
+ * receive a ClientHello as long as this. If we do it will get dropped
+ * in the record length check below.
+ */
+ n = BIO_read(rbio, buf, SSL3_RT_MAX_PLAIN_LENGTH);
+
+ if (n <= 0) {
+ if(BIO_should_retry(rbio)) {
+ /* Non-blocking IO */
+ goto end;
+ }
+ return -1;
+ }
+
+ /* If we hit any problems we need to clear this packet from the BIO */
+ clearpkt = 1;
+
+ if (!PACKET_buf_init(&pkt, buf, n)) {
+ SSLerr(SSL_F_DTLS1_LISTEN, ERR_R_INTERNAL_ERROR);
+ return -1;
+ }
+
+ /*
+ * Parse the received record. If there are any problems with it we just
+ * dump it - with no alert. RFC6347 says this "Unlike TLS, DTLS is
+ * resilient in the face of invalid records (e.g., invalid formatting,
+ * length, MAC, etc.). In general, invalid records SHOULD be silently
+ * discarded, thus preserving the association; however, an error MAY be
+ * logged for diagnostic purposes."
+ */
+
+ /* this packet contained a partial record, dump it */
+ if (n < DTLS1_RT_HEADER_LENGTH) {
+ SSLerr(SSL_F_DTLS1_LISTEN, SSL_R_RECORD_TOO_SMALL);
+ goto end;
+ }
+
+ if (s->msg_callback)
+ s->msg_callback(0, 0, SSL3_RT_HEADER, buf,
+ DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
+
+ /* Get the record header */
+ if (!PACKET_get_1(&pkt, &rectype)
+ || !PACKET_get_1(&pkt, &versmajor)) {
+ SSLerr(SSL_F_DTLS1_LISTEN, SSL_R_LENGTH_MISMATCH);
+ goto end;
+ }
+
+ if (rectype != SSL3_RT_HANDSHAKE) {
+ SSLerr(SSL_F_DTLS1_LISTEN, SSL_R_UNEXPECTED_MESSAGE);
+ goto end;
+ }
+
+ /*
+ * Check record version number. We only check that the major version is
+ * the same.
+ */
+ if (versmajor != DTLS1_VERSION_MAJOR) {
+ SSLerr(SSL_F_DTLS1_LISTEN, SSL_R_BAD_PROTOCOL_VERSION_NUMBER);
+ goto end;
+ }
+
+ if (!PACKET_forward(&pkt, 1)
+ /* Save the sequence number: 64 bits, with top 2 bytes = epoch */
+ || !PACKET_copy_bytes(&pkt, seq, SEQ_NUM_SIZE)
+ || !PACKET_get_length_prefixed_2(&pkt, &msgpkt)
+ || PACKET_remaining(&pkt) != 0) {
+ SSLerr(SSL_F_DTLS1_LISTEN, SSL_R_LENGTH_MISMATCH);
+ goto end;
+ }
+
+ /* This is an initial ClientHello so the epoch has to be 0 */
+ if (seq[0] != 0 || seq[1] != 0) {
+ SSLerr(SSL_F_DTLS1_LISTEN, SSL_R_UNEXPECTED_MESSAGE);
+ goto end;
+ }
+
+ /* Get a pointer to the raw message for the later callback */
+ data = PACKET_data(&msgpkt);
+
+ /* Finished processing the record header, now process the message */
+ if (!PACKET_get_1(&msgpkt, &msgtype)
+ || !PACKET_get_net_3(&msgpkt, &msglen)
+ || !PACKET_get_net_2(&msgpkt, &msgseq)
+ || !PACKET_get_net_3(&msgpkt, &fragoff)
+ || !PACKET_get_net_3(&msgpkt, &fraglen)
+ || !PACKET_get_sub_packet(&msgpkt, &msgpayload, msglen)
+ || PACKET_remaining(&msgpkt) != 0) {
+ SSLerr(SSL_F_DTLS1_LISTEN, SSL_R_LENGTH_MISMATCH);
+ goto end;
+ }
+
+ if (msgtype != SSL3_MT_CLIENT_HELLO) {
+ SSLerr(SSL_F_DTLS1_LISTEN, SSL_R_UNEXPECTED_MESSAGE);
+ goto end;
+ }
+
+ /* Message sequence number can only be 0 or 1 */
+ if(msgseq > 2) {
+ SSLerr(SSL_F_DTLS1_LISTEN, SSL_R_INVALID_SEQUENCE_NUMBER);
+ goto end;
+ }
+
+ /* We don't support a fragmented ClientHello whilst listening */
+ if (fragoff != 0 || fraglen != msglen) {
+ SSLerr(SSL_F_DTLS1_LISTEN, SSL_R_FRAGMENTED_CLIENT_HELLO);
+ goto end;
+ }
+
+ if (s->msg_callback)
+ s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, data,
+ msglen + DTLS1_HM_HEADER_LENGTH, s,
+ s->msg_callback_arg);
+
+ if (!PACKET_get_net_2(&msgpayload, &clientvers)) {
+ SSLerr(SSL_F_DTLS1_LISTEN, SSL_R_LENGTH_MISMATCH);
+ goto end;
+ }
+
+ /*
+ * Verify client version is supported
+ */
+ if ((clientvers > (unsigned int)s->method->version &&
+ s->method->version != DTLS_ANY_VERSION)) {
+ SSLerr(SSL_F_DTLS1_LISTEN, SSL_R_WRONG_VERSION_NUMBER);
+ goto end;
+ }
+
+ if (!PACKET_forward(&msgpayload, SSL3_RANDOM_SIZE)
+ || !PACKET_get_length_prefixed_1(&msgpayload, &session)
+ || !PACKET_get_length_prefixed_1(&msgpayload, &cookiepkt)) {
+ SSLerr(SSL_F_DTLS1_LISTEN, SSL_R_LENGTH_MISMATCH);
+ goto end;
+ }
+
+ /*
+ * Check if we have a cookie or not. If not we need to send a
+ * HelloVerifyRequest.
+ */
+ if (PACKET_remaining(&cookiepkt) == 0) {
+ next = LISTEN_SEND_VERIFY_REQUEST;
+ } else {
+ /*
+ * We have a cookie, so lets check it.
+ */
+ if (s->ctx->app_verify_cookie_cb == NULL) {
+ SSLerr(SSL_F_DTLS1_LISTEN, SSL_R_NO_VERIFY_COOKIE_CALLBACK);
+ /* This is fatal */
+ return -1;
+ }
+ if (s->ctx->app_verify_cookie_cb(s, PACKET_data(&cookiepkt),
+ PACKET_remaining(&cookiepkt)) ==
+ 0) {
+ /*
+ * We treat invalid cookies in the same was as no cookie as
+ * per RFC6347
+ */
+ next = LISTEN_SEND_VERIFY_REQUEST;
+ } else {
+ /* Cookie verification succeeded */
+ next = LISTEN_SUCCESS;
+ }
+ }
+
+ if (next == LISTEN_SEND_VERIFY_REQUEST) {
+ /*
+ * There was no cookie in the ClientHello so we need to send a
+ * HelloVerifyRequest. If this fails we do not worry about trying
+ * to resend, we just drop it.
+ */
+
+ /*
+ * Dump the read packet, we don't need it any more. Ignore return
+ * value
+ */
+ BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_PEEK_MODE, 0, NULL);
+ BIO_read(rbio, buf, SSL3_RT_MAX_PLAIN_LENGTH);
+ BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_PEEK_MODE, 1, NULL);
+
+ /* Generate the cookie */
+ if (s->ctx->app_gen_cookie_cb == NULL ||
+ s->ctx->app_gen_cookie_cb(s, cookie, &cookielen) == 0 ||
+ cookielen > 255) {
+ SSLerr(SSL_F_DTLS1_LISTEN, SSL_R_COOKIE_GEN_CALLBACK_FAILURE);
+ /* This is fatal */
+ return -1;
+ }
+
+ p = &buf[DTLS1_RT_HEADER_LENGTH];
+ msglen = dtls_raw_hello_verify_request(p + DTLS1_HM_HEADER_LENGTH,
+ cookie, cookielen);
+
+ *p++ = DTLS1_MT_HELLO_VERIFY_REQUEST;
+
+ /* Message length */
+ l2n3(msglen, p);
+
+ /* Message sequence number is always 0 for a HelloVerifyRequest */
+ s2n(0, p);
+
+ /*
+ * We never fragment a HelloVerifyRequest, so fragment offset is 0
+ * and fragment length is message length
+ */
+ l2n3(0, p);
+ l2n3(msglen, p);
+
+ /* Set reclen equal to length of whole handshake message */
+ reclen = msglen + DTLS1_HM_HEADER_LENGTH;
+
+ /* Add the record header */
+ p = buf;
+
+ *(p++) = SSL3_RT_HANDSHAKE;
+ /*
+ * Special case: for hello verify request, client version 1.0 and we
+ * haven't decided which version to use yet send back using version
+ * 1.0 header: otherwise some clients will ignore it.
+ */
+ if (s->method->version == DTLS_ANY_VERSION) {
+ *(p++) = DTLS1_VERSION >> 8;
+ *(p++) = DTLS1_VERSION & 0xff;
+ } else {
+ *(p++) = s->version >> 8;
+ *(p++) = s->version & 0xff;
+ }
+
+ /*
+ * Record sequence number is always the same as in the received
+ * ClientHello
+ */
+ memcpy(p, seq, SEQ_NUM_SIZE);
+ p += SEQ_NUM_SIZE;
+
+ /* Length */
+ s2n(reclen, p);
+
+ /*
+ * Set reclen equal to length of whole record including record
+ * header
+ */
+ reclen += DTLS1_RT_HEADER_LENGTH;
+
+ if (s->msg_callback)
+ s->msg_callback(1, 0, SSL3_RT_HEADER, buf,
+ DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
+
+ /*
+ * This is unneccessary if rbio and wbio are one and the same - but
+ * maybe they're not.
+ */
+ if(BIO_dgram_get_peer(rbio, &tmpclient) <= 0
+ || BIO_dgram_set_peer(wbio, &tmpclient) <= 0) {
+ SSLerr(SSL_F_DTLS1_LISTEN, ERR_R_INTERNAL_ERROR);
+ goto end;
+ }
+
+ if (BIO_write(wbio, buf, reclen) < (int)reclen) {
+ if(BIO_should_retry(wbio)) {
+ /*
+ * Non-blocking IO...but we're stateless, so we're just
+ * going to drop this packet.
+ */
+ goto end;
+ }
+ return -1;
+ }
+
+ if (BIO_flush(wbio) <= 0) {
+ if(BIO_should_retry(wbio)) {
+ /*
+ * Non-blocking IO...but we're stateless, so we're just
+ * going to drop this packet.
+ */
+ goto end;
+ }
+ return -1;
+ }
+ }
+ } while (next != LISTEN_SUCCESS);
+
+ /*
+ * Set expected sequence numbers to continue the handshake.
+ */
+ s->d1->handshake_read_seq = 1;
+ s->d1->handshake_write_seq = 1;
+ s->d1->next_handshake_write_seq = 1;
+ DTLS_RECORD_LAYER_set_write_sequence(&s->rlayer, seq);
+
+ /*
+ * We are doing cookie exchange, so make sure we set that option in the
+ * SSL object
+ */
+ SSL_set_options(s, SSL_OP_COOKIE_EXCHANGE);
+
+ /*
+ * Tell the state machine that we've done the initial hello verify
+ * exchange
+ */
+ ossl_statem_set_hello_verify_done(s);
+
+ if(BIO_dgram_get_peer(rbio, client) <= 0) {
+ SSLerr(SSL_F_DTLS1_LISTEN, ERR_R_INTERNAL_ERROR);
+ return -1;
+ }
+
+ ret = 1;
+ clearpkt = 0;
+end:
+ BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_PEEK_MODE, 0, NULL);
+ if (clearpkt) {
+ /* Dump this packet. Ignore return value */
+ BIO_read(rbio, buf, SSL3_RT_MAX_PLAIN_LENGTH);
+ }
+ return ret;
+}
+
+static int dtls1_set_handshake_header(SSL *s, int htype, unsigned long len)
+{
+ unsigned char *p = (unsigned char *)s->init_buf->data;
+ dtls1_set_message_header(s, p, htype, len, 0, len);
+ s->init_num = (int)len + DTLS1_HM_HEADER_LENGTH;
+ s->init_off = 0;
+ /* Buffer the message to handle re-xmits */
+
+ if (!dtls1_buffer_message(s, 0))
+ return 0;
+
+ return 1;
+}
+
+static int dtls1_handshake_write(SSL *s)
+{
+ return dtls1_do_write(s, SSL3_RT_HANDSHAKE);
+}
+
+#ifndef OPENSSL_NO_HEARTBEATS
+int dtls1_process_heartbeat(SSL *s, unsigned char *p, unsigned int length)
+{
+ unsigned char *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,
+ p, length, s, s->msg_callback_arg);
+
+ /* Read type and payload length first */
+ if (1 + 2 + 16 > length)
+ return 0; /* silently discard */
+ if (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 > 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 */
+ if (RAND_bytes(bp, padding) <= 0) {
+ OPENSSL_free(buffer);
+ return -1;
+ }
+
+ 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 = -1;
+ 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) || ossl_statem_get_in_handshake(s)) {
+ SSLerr(SSL_F_DTLS1_HEARTBEAT, SSL_R_UNEXPECTED_MESSAGE);
+ return -1;
+ }
+
+ /*-
+ * 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 */
+ if (RAND_bytes(p, 16) <= 0) {
+ SSLerr(SSL_F_DTLS1_HEARTBEAT, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+ p += 16;
+ /* Random padding */
+ if (RAND_bytes(p, padding) <= 0) {
+ SSLerr(SSL_F_DTLS1_HEARTBEAT, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+
+ 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;
+ }
+
+ err:
+ OPENSSL_free(buf);
+
+ return ret;
+}
+#endif
+
+int dtls1_shutdown(SSL *s)
+{
+ int ret;
+#ifndef OPENSSL_NO_SCTP
+ BIO *wbio;
+
+ wbio = SSL_get_wbio(s);
+ if (wbio != NULL && BIO_dgram_is_sctp(wbio) &&
+ !(s->shutdown & SSL_SENT_SHUTDOWN)) {
+ ret = BIO_dgram_sctp_wait_for_dry(wbio);
+ 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;
+}
+
+int dtls1_query_mtu(SSL *s)
+{
+ if (s->d1->link_mtu) {
+ s->d1->mtu =
+ s->d1->link_mtu - BIO_dgram_get_mtu_overhead(SSL_get_wbio(s));
+ s->d1->link_mtu = 0;
+ }
+
+ /* AHA! Figure out the MTU, and stick to the right size */
+ if (s->d1->mtu < dtls1_min_mtu(s)) {
+ if (!(SSL_get_options(s) & SSL_OP_NO_QUERY_MTU)) {
+ s->d1->mtu =
+ BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL);
+
+ /*
+ * I've seen the kernel return bogus numbers when it doesn't know
+ * (initial write), so just make sure we have a reasonable number
+ */
+ if (s->d1->mtu < dtls1_min_mtu(s)) {
+ /* Set to min mtu */
+ s->d1->mtu = dtls1_min_mtu(s);
+ BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SET_MTU,
+ s->d1->mtu, NULL);
+ }
+ } else
+ return 0;
+ }
+ return 1;
+}
+
+static unsigned int dtls1_link_min_mtu(void)
+{
+ return (g_probable_mtu[(sizeof(g_probable_mtu) /
+ sizeof(g_probable_mtu[0])) - 1]);
+}
+
+unsigned int dtls1_min_mtu(SSL *s)
+{
+ return dtls1_link_min_mtu() - BIO_dgram_get_mtu_overhead(SSL_get_wbio(s));
+}