/*
- * DTLS implementation written by Nagendra Modadugu
- * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
- */
-/* ====================================================================
- * Copyright (c) 1999-2005 The OpenSSL Project. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- * 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
- * the documentation and/or other materials provided with the
- * distribution.
- *
- * 3. All advertising materials mentioning features or use of this
- * software must display the following acknowledgment:
- * "This product includes software developed by the OpenSSL Project
- * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
- *
- * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
- * endorse or promote products derived from this software without
- * prior written permission. For written permission, please contact
- * openssl-core@OpenSSL.org.
- *
- * 5. Products derived from this software may not be called "OpenSSL"
- * nor may "OpenSSL" appear in their names without prior written
- * permission of the OpenSSL Project.
- *
- * 6. Redistributions of any form whatsoever must retain the following
- * acknowledgment:
- * "This product includes software developed by the OpenSSL Project
- * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
- *
- * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
- * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
- * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
- * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
- * OF THE POSSIBILITY OF SUCH DAMAGE.
- * ====================================================================
- *
- * This product includes cryptographic software written by Eric Young
- * (eay@cryptsoft.com). This product includes software written by Tim
- * Hudson (tjh@cryptsoft.com).
+ * Copyright 2005-2016 The OpenSSL Project Authors. All Rights Reserved.
*
+ * Licensed under the OpenSSL license (the "License"). You may not use
+ * this file except in compliance with the License. You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
*/
#include <stdio.h>
#include <openssl/rand.h>
#include "ssl_locl.h"
-#if defined(OPENSSL_SYS_VMS)
-# include <sys/timeb.h>
-#elif defined(OPENSSL_SYS_VXWORKS)
+#if 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);
-static int dtls1_set_handshake_header(SSL *s, int type, unsigned long len);
static int dtls1_handshake_write(SSL *s);
-static unsigned int dtls1_link_min_mtu(void);
+static size_t dtls1_link_min_mtu(void);
/* XDTLS: figure out the right values */
-static const unsigned int g_probable_mtu[] = { 1500, 512, 256 };
+static const size_t g_probable_mtu[] = { 1500, 512, 256 };
const SSL3_ENC_METHOD DTLSv1_enc_data = {
tls1_enc,
tls1_generate_master_secret,
tls1_change_cipher_state,
tls1_final_finish_mac,
- TLS1_FINISH_MAC_LENGTH,
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_close_construct_packet,
dtls1_handshake_write
};
tls1_generate_master_secret,
tls1_change_cipher_state,
tls1_final_finish_mac,
- TLS1_FINISH_MAC_LENGTH,
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_close_construct_packet,
dtls1_handshake_write
};
if (!DTLS_RECORD_LAYER_new(&s->rlayer)) {
return 0;
}
-
+
if (!ssl3_new(s))
return (0);
if ((d1 = OPENSSL_zalloc(sizeof(*d1))) == NULL) {
}
static void dtls1_clear_queues(SSL *s)
+{
+ dtls1_clear_received_buffer(s);
+ dtls1_clear_sent_buffer(s);
+}
+
+void dtls1_clear_received_buffer(SSL *s)
{
pitem *item = NULL;
hm_fragment *frag = NULL;
dtls1_hm_fragment_free(frag);
pitem_free(item);
}
+}
+
+void dtls1_clear_sent_buffer(SSL *s)
+{
+ pitem *item = NULL;
+ hm_fragment *frag = NULL;
while ((item = pqueue_pop(s->d1->sent_messages)) != NULL) {
frag = (hm_fragment *)item->data;
}
}
+
void dtls1_free(SSL *s)
{
DTLS_RECORD_LAYER_free(&s->rlayer);
{
pqueue *buffered_messages;
pqueue *sent_messages;
- unsigned int mtu;
- unsigned int link_mtu;
+ size_t mtu;
+ size_t link_mtu;
DTLS_RECORD_LAYER_clear(&s->rlayer);
}
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)
+
+ if (s->method->version == DTLS_ANY_VERSION)
s->version = DTLS_MAX_VERSION;
+#ifndef OPENSSL_NO_DTLS1_METHOD
+ else if (s->options & SSL_OP_CISCO_ANYCONNECT)
+ s->client_version = s->version = DTLS1_BAD_VER;
+#endif
else
s->version = s->method->version;
}
/*
* If remaining time is less than 15 ms, set it to 0 to prevent issues
- * because of small devergences with socket timeouts.
+ * because of small divergences with socket timeouts.
*/
if (timeleft->tv_sec == 0 && timeleft->tv_usec < 15000) {
memset(timeleft, 0, sizeof(*timeleft));
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);
+ dtls1_clear_sent_buffer(s);
}
int dtls1_check_timeout_num(SSL *s)
{
- unsigned int mtu;
+ size_t mtu;
s->d1->timeout.num_alerts++;
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);
+ 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.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);
GetSystemTime(&st);
SystemTimeToFileTime(&st, &now.ft);
+ /* re-bias to 1/1/1970 */
# ifdef __MINGW32__
now.ul -= 116444736000000000ULL;
# else
- now.ul -= 116444736000000000UI64; /* re-bias to 1/1/1970 */
+ /* *INDENT-OFF* */
+ now.ul -= 116444736000000000UI64;
+ /* *INDENT-ON* */
# 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;
#else
gettimeofday(t, NULL);
#endif
}
-
#define LISTEN_SUCCESS 2
#define LISTEN_SEND_VERIFY_REQUEST 1
-
+#ifndef OPENSSL_NO_SOCK
int DTLSv1_listen(SSL *s, BIO_ADDR *client)
{
int next, n, ret = 0, clearpkt = 0;
unsigned char cookie[DTLS1_COOKIE_LENGTH];
unsigned char seq[SEQ_NUM_SIZE];
const unsigned char *data;
- unsigned char *p, *buf;
- unsigned long reclen, fragoff, fraglen, msglen;
+ unsigned char *buf;
+ size_t fragoff, fraglen, msglen;
unsigned int rectype, versmajor, msgseq, msgtype, clientvers, cookielen;
BIO *rbio, *wbio;
BUF_MEM *bufm;
BIO_ADDR *tmpclient = NULL;
PACKET pkt, msgpkt, msgpayload, session, cookiepkt;
+ if (s->handshake_func == NULL) {
+ /* Not properly initialized yet */
+ SSL_set_accept_state(s);
+ }
+
/* Ensure there is no state left over from a previous invocation */
if (!SSL_clear(s))
return -1;
rbio = SSL_get_rbio(s);
wbio = SSL_get_wbio(s);
- if(!rbio || !wbio) {
+ if (!rbio || !wbio) {
SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_BIO_NOT_SET);
return -1;
}
n = BIO_read(rbio, buf, SSL3_RT_MAX_PLAIN_LENGTH);
if (n <= 0) {
- if(BIO_should_retry(rbio)) {
+ if (BIO_should_retry(rbio)) {
/* Non-blocking IO */
goto end;
}
goto end;
}
- if (rectype != SSL3_RT_HANDSHAKE) {
+ if (rectype != SSL3_RT_HANDSHAKE) {
SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_UNEXPECTED_MESSAGE);
goto end;
}
/* Finished processing the record header, now process the message */
if (!PACKET_get_1(&msgpkt, &msgtype)
- || !PACKET_get_net_3(&msgpkt, &msglen)
+ || !PACKET_get_net_3_len(&msgpkt, &msglen)
|| !PACKET_get_net_2(&msgpkt, &msgseq)
- || !PACKET_get_net_3(&msgpkt, &fragoff)
- || !PACKET_get_net_3(&msgpkt, &fraglen)
+ || !PACKET_get_net_3_len(&msgpkt, &fragoff)
+ || !PACKET_get_net_3_len(&msgpkt, &fraglen)
|| !PACKET_get_sub_packet(&msgpkt, &msgpayload, fraglen)
|| PACKET_remaining(&msgpkt) != 0) {
SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_LENGTH_MISMATCH);
}
/* Message sequence number can only be 0 or 1 */
- if(msgseq > 2) {
+ if (msgseq > 2) {
SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_INVALID_SEQUENCE_NUMBER);
goto end;
}
return -1;
}
if (s->ctx->app_verify_cookie_cb(s, PACKET_data(&cookiepkt),
- PACKET_remaining(&cookiepkt)) ==
- 0) {
+ (unsigned int)PACKET_remaining(&cookiepkt)) == 0) {
/*
* We treat invalid cookies in the same was as no cookie as
* per RFC6347
}
if (next == LISTEN_SEND_VERIFY_REQUEST) {
+ WPACKET wpkt;
+ unsigned int version;
+ size_t wreclen;
+
/*
* There was no cookie in the ClientHello so we need to send a
* HelloVerifyRequest. If this fails we do not worry about trying
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;
+ version = (s->method->version == DTLS_ANY_VERSION) ? DTLS1_VERSION
+ : s->version;
+
+ /* Construct the record and message headers */
+ if (!WPACKET_init(&wpkt, s->init_buf)
+ || !WPACKET_put_bytes_u8(&wpkt, SSL3_RT_HANDSHAKE)
+ || !WPACKET_put_bytes_u16(&wpkt, version)
+ /*
+ * Record sequence number is always the same as in the
+ * received ClientHello
+ */
+ || !WPACKET_memcpy(&wpkt, seq, SEQ_NUM_SIZE)
+ /* End of record, start sub packet for message */
+ || !WPACKET_start_sub_packet_u16(&wpkt)
+ /* Message type */
+ || !WPACKET_put_bytes_u8(&wpkt,
+ DTLS1_MT_HELLO_VERIFY_REQUEST)
+ /*
+ * Message length - doesn't follow normal TLS convention:
+ * the length isn't the last thing in the message header.
+ * We'll need to fill this in later when we know the
+ * length. Set it to zero for now
+ */
+ || !WPACKET_put_bytes_u24(&wpkt, 0)
+ /*
+ * Message sequence number is always 0 for a
+ * HelloVerifyRequest
+ */
+ || !WPACKET_put_bytes_u16(&wpkt, 0)
+ /*
+ * We never fragment a HelloVerifyRequest, so fragment
+ * offset is 0
+ */
+ || !WPACKET_put_bytes_u24(&wpkt, 0)
+ /*
+ * Fragment length is the same as message length, but
+ * this *is* the last thing in the message header so we
+ * can just start a sub-packet. No need to come back
+ * later for this one.
+ */
+ || !WPACKET_start_sub_packet_u24(&wpkt)
+ /* Create the actual HelloVerifyRequest body */
+ || !dtls_raw_hello_verify_request(&wpkt, cookie, cookielen)
+ /* Close message body */
+ || !WPACKET_close(&wpkt)
+ /* Close record body */
+ || !WPACKET_close(&wpkt)
+ || !WPACKET_get_total_written(&wpkt, &wreclen)
+ || !WPACKET_finish(&wpkt)) {
+ SSLerr(SSL_F_DTLSV1_LISTEN, ERR_R_INTERNAL_ERROR);
+ WPACKET_cleanup(&wpkt);
+ /* This is fatal */
+ return -1;
}
/*
- * 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
+ * Fix up the message len in the message header. Its the same as the
+ * fragment len which has been filled in by WPACKET, so just copy
+ * that. Destination for the message len is after the record header
+ * plus one byte for the message content type. The source is the
+ * last 3 bytes of the message header
*/
- reclen += DTLS1_RT_HEADER_LENGTH;
+ memcpy(&buf[DTLS1_RT_HEADER_LENGTH + 1],
+ &buf[DTLS1_RT_HEADER_LENGTH + DTLS1_HM_HEADER_LENGTH - 3],
+ 3);
if (s->msg_callback)
s->msg_callback(1, 0, SSL3_RT_HEADER, buf,
DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
-
if ((tmpclient = BIO_ADDR_new()) == NULL) {
SSLerr(SSL_F_DTLSV1_LISTEN, ERR_R_MALLOC_FAILURE);
goto end;
}
/*
- * This is unneccessary if rbio and wbio are one and the same - but
+ * This is unnecessary if rbio and wbio are one and the same - but
* maybe they're not. We ignore errors here - some BIOs do not
* support this.
*/
- if(BIO_dgram_get_peer(rbio, tmpclient) > 0) {
+ if (BIO_dgram_get_peer(rbio, tmpclient) > 0) {
(void)BIO_dgram_set_peer(wbio, tmpclient);
}
BIO_ADDR_free(tmpclient);
tmpclient = NULL;
- if (BIO_write(wbio, buf, reclen) < (int)reclen) {
- if(BIO_should_retry(wbio)) {
+ /* TODO(size_t): convert this call */
+ if (BIO_write(wbio, buf, wreclen) < (int)wreclen) {
+ if (BIO_should_retry(wbio)) {
/*
* Non-blocking IO...but we're stateless, so we're just
* going to drop this packet.
}
if (BIO_flush(wbio) <= 0) {
- if(BIO_should_retry(wbio)) {
+ if (BIO_should_retry(wbio)) {
/*
* Non-blocking IO...but we're stateless, so we're just
* going to drop this packet.
*/
ossl_statem_set_hello_verify_done(s);
- /* Some BIOs may not support this. If we fail we clear the client address */
+ /*
+ * Some BIOs may not support this. If we fail we clear the client address
+ */
if (BIO_dgram_get_peer(rbio, client) <= 0)
BIO_ADDR_clear(client);
ret = 1;
clearpkt = 0;
-end:
+ end:
BIO_ADDR_free(tmpclient);
BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_PEEK_MODE, 0, NULL);
if (clearpkt) {
}
return ret;
}
-
-static int dtls1_set_handshake_header(SSL *s, int htype, unsigned long len)
-{
- dtls1_set_message_header(s, 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;
-}
+#endif
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, DTLS1_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, DTLS1_RT_HEARTBEAT, buffer, write_length);
-
- if (r >= 0 && s->msg_callback)
- s->msg_callback(1, s->version, DTLS1_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_DTLSEXT_HB_ENABLED) ||
- s->tlsext_heartbeat & SSL_DTLSEXT_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, DTLS1_RT_HEARTBEAT, buf, 3 + payload + padding);
- if (ret >= 0) {
- if (s->msg_callback)
- s->msg_callback(1, s->version, DTLS1_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;
/* 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);
+ (long)s->d1->mtu, NULL);
}
} else
return 0;
return 1;
}
-static unsigned int dtls1_link_min_mtu(void)
+static size_t 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)
+size_t dtls1_min_mtu(SSL *s)
{
return dtls1_link_min_mtu() - BIO_dgram_get_mtu_overhead(SSL_get_wbio(s));
}
+
+size_t DTLS_get_data_mtu(const SSL *s)
+{
+ size_t mac_overhead, int_overhead, blocksize, ext_overhead;
+ const SSL_CIPHER *ciph = SSL_get_current_cipher(s);
+ size_t mtu = s->d1->mtu;
+
+ if (ciph == NULL)
+ return 0;
+
+ if (!ssl_cipher_get_overhead(ciph, &mac_overhead, &int_overhead,
+ &blocksize, &ext_overhead))
+ return 0;
+
+ if (SSL_READ_ETM(s))
+ ext_overhead += mac_overhead;
+ else
+ int_overhead += mac_overhead;
+
+ /* Subtract external overhead (e.g. IV/nonce, separate MAC) */
+ if (ext_overhead + DTLS1_RT_HEADER_LENGTH >= mtu)
+ return 0;
+ mtu -= ext_overhead + DTLS1_RT_HEADER_LENGTH;
+
+ /* Round encrypted payload down to cipher block size (for CBC etc.)
+ * No check for overflow since 'mtu % blocksize' cannot exceed mtu. */
+ if (blocksize)
+ mtu -= (mtu % blocksize);
+
+ /* Subtract internal overhead (e.g. CBC padding len byte) */
+ if (int_overhead >= mtu)
+ return 0;
+ mtu -= int_overhead;
+
+ return mtu;
+}