-/* ssl/d1_lib.c */
/*
- * 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>
#define USE_SOCKETS
#include <openssl/objects.h>
+#include <openssl/rand.h>
#include "ssl_locl.h"
-#if defined(OPENSSL_SYS_VMS)
-# include <sys/timeb.h>
+#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 void dtls1_set_handshake_header(SSL *s, int type, unsigned long len);
static int dtls1_handshake_write(SSL *s);
-const char dtls1_version_str[] = "DTLSv1" OPENSSL_VERSION_PTEXT;
-int dtls1_listen(SSL *s, struct sockaddr *client);
+static size_t dtls1_link_min_mtu(void);
+
+/* XDTLS: figure out the right values */
+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,
- 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_close_construct_packet,
dtls1_handshake_write
};
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_close_construct_packet,
dtls1_handshake_write
};
{
DTLS1_STATE *d1;
+ if (!DTLS_RECORD_LAYER_new(&s->rlayer)) {
+ return 0;
+ }
+
if (!ssl3_new(s))
return (0);
- if ((d1 = OPENSSL_malloc(sizeof *d1)) == NULL) {
+ if ((d1 = OPENSSL_zalloc(sizeof(*d1))) == NULL) {
ssl3_free(s);
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);
d1->link_mtu = 0;
d1->mtu = 0;
- 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);
+ 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);
}
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_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) {
frag = (hm_fragment *)item->data;
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;
dtls1_hm_fragment_free(frag);
pitem_free(item);
}
-
- while ((item = pqueue_pop(s->d1->buffered_app_data.q)) != NULL) {
- rdata = (DTLS1_RECORD_DATA *)item->data;
- if (rdata->rbuf.buf) {
- OPENSSL_free(rdata->rbuf.buf);
- }
- OPENSSL_free(item->data);
- pitem_free(item);
- }
}
+
void dtls1_free(SSL *s)
{
+ DTLS_RECORD_LAYER_free(&s->rlayer);
+
ssl3_free(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);
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;
- unsigned int mtu;
- unsigned int link_mtu;
+ pqueue *buffered_messages;
+ pqueue *sent_messages;
+ size_t mtu;
+ size_t link_mtu;
+
+ DTLS_RECORD_LAYER_clear(&s->rlayer);
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;
mtu = s->d1->mtu;
link_mtu = s->d1->link_mtu;
dtls1_clear_queues(s);
- memset(s->d1, 0, sizeof(*(s->d1)));
+ memset(s->d1, 0, sizeof(*s->d1));
if (s->server) {
s->d1->cookie_len = sizeof(s->d1->cookie);
s->d1->link_mtu = link_mtu;
}
- 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)
+
+ 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;
- else if (s->method->version == DTLS_ANY_VERSION)
- s->version = DTLS1_2_VERSION;
+#endif
else
s->version = s->method->version;
}
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;
return (ret);
}
-/*
- * As it's impossible to use stream ciphers in "datagram" mode, this
- * simple filter is designed to disengage them in DTLS. Unfortunately
- * there is no universal way to identify stream SSL_CIPHER, so we have
- * to explicitly list their SSL_* codes. Currently RC4 is the only one
- * 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);
-
- if (ciph != NULL) {
- if (ciph->algorithm_enc == SSL_RC4)
- return NULL;
- }
-
- return ciph;
-}
-
void dtls1_start_timer(SSL *s)
{
#ifndef OPENSSL_NO_SCTP
/* Disable timer for SCTP */
if (BIO_dgram_is_sctp(SSL_get_wbio(s))) {
- memset(&(s->d1->next_timeout), 0, sizeof(struct timeval));
+ memset(&s->d1->next_timeout, 0, sizeof(s->d1->next_timeout));
return;
}
#endif
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));
+ memset(timeleft, 0, sizeof(*timeleft));
return timeleft;
}
/*
* 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(struct timeval));
+ memset(timeleft, 0, sizeof(*timeleft));
}
return timeleft;
void dtls1_stop_timer(SSL *s)
{
/* Reset everything */
- memset(&(s->d1->timeout), 0, sizeof(struct dtls1_timeout_st));
- memset(&(s->d1->next_timeout), 0, sizeof(struct timeval));
+ 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);
+ 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
}
-int dtls1_listen(SSL *s, struct sockaddr *client)
+#define LISTEN_SUCCESS 2
+#define LISTEN_SEND_VERIFY_REQUEST 1
+
+#ifndef OPENSSL_NO_SOCK
+int DTLSv1_listen(SSL *s, BIO_ADDR *client)
{
- int ret;
+ 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 *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 */
- SSL_clear(s);
+ 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_DTLSV1_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 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_DTLSV1_LISTEN, SSL_R_UNSUPPORTED_SSL_VERSION);
+ return -1;
+ }
+
+ if (s->init_buf == NULL) {
+ if ((bufm = BUF_MEM_new()) == NULL) {
+ SSLerr(SSL_F_DTLSV1_LISTEN, ERR_R_MALLOC_FAILURE);
+ return -1;
+ }
+
+ if (!BUF_MEM_grow(bufm, SSL3_RT_MAX_PLAIN_LENGTH)) {
+ BUF_MEM_free(bufm);
+ SSLerr(SSL_F_DTLSV1_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_DTLSV1_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_DTLSV1_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_DTLSV1_LISTEN, SSL_R_LENGTH_MISMATCH);
+ goto end;
+ }
+
+ if (rectype != SSL3_RT_HANDSHAKE) {
+ SSLerr(SSL_F_DTLSV1_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_DTLSV1_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)) {
+ SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_LENGTH_MISMATCH);
+ goto end;
+ }
+ /*
+ * We allow data remaining at the end of the packet because there could
+ * be a second record (but we ignore it)
+ */
+
+ /* This is an initial ClientHello so the epoch has to be 0 */
+ if (seq[0] != 0 || seq[1] != 0) {
+ SSLerr(SSL_F_DTLSV1_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_len(&msgpkt, &msglen)
+ || !PACKET_get_net_2(&msgpkt, &msgseq)
+ || !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);
+ goto end;
+ }
+
+ if (msgtype != SSL3_MT_CLIENT_HELLO) {
+ SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_UNEXPECTED_MESSAGE);
+ goto end;
+ }
+
+ /* Message sequence number can only be 0 or 1 */
+ if (msgseq > 2) {
+ SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_INVALID_SEQUENCE_NUMBER);
+ goto end;
+ }
+
+ /*
+ * We don't support fragment reassembly for ClientHellos whilst
+ * listening because that would require server side state (which is
+ * against the whole point of the ClientHello/HelloVerifyRequest
+ * mechanism). Instead we only look at the first ClientHello fragment
+ * and require that the cookie must be contained within it.
+ */
+ if (fragoff != 0 || fraglen > msglen) {
+ /* Non initial ClientHello fragment (or bad fragment) */
+ SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_FRAGMENTED_CLIENT_HELLO);
+ goto end;
+ }
+
+ if (s->msg_callback)
+ s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, data,
+ fraglen + DTLS1_HM_HEADER_LENGTH, s,
+ s->msg_callback_arg);
+
+ if (!PACKET_get_net_2(&msgpayload, &clientvers)) {
+ SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_LENGTH_MISMATCH);
+ goto end;
+ }
+
+ /*
+ * Verify client version is supported
+ */
+ if (DTLS_VERSION_LT(clientvers, (unsigned int)s->method->version) &&
+ s->method->version != DTLS_ANY_VERSION) {
+ SSLerr(SSL_F_DTLSV1_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)) {
+ /*
+ * Could be malformed or the cookie does not fit within the initial
+ * ClientHello fragment. Either way we can't handle it.
+ */
+ SSLerr(SSL_F_DTLSV1_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_DTLSV1_LISTEN, SSL_R_NO_VERIFY_COOKIE_CALLBACK);
+ /* This is fatal */
+ return -1;
+ }
+ if (s->ctx->app_verify_cookie_cb(s, PACKET_data(&cookiepkt),
+ (unsigned int)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) {
+ 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
+ * 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_DTLSV1_LISTEN, SSL_R_COOKIE_GEN_CALLBACK_FAILURE);
+ /* This is fatal */
+ return -1;
+ }
+
+ /*
+ * 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.
+ */
+ 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;
+ }
+
+ /*
+ * 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
+ */
+ 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 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) {
+ (void)BIO_dgram_set_peer(wbio, tmpclient);
+ }
+ BIO_ADDR_free(tmpclient);
+ tmpclient = NULL;
+
+ /* 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.
+ */
+ 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);
- s->d1->listen = 1;
- ret = SSL_accept(s);
- if (ret <= 0)
- return ret;
+ /*
+ * Tell the state machine that we've done the initial hello verify
+ * exchange
+ */
+ ossl_statem_set_hello_verify_done(s);
+
+ /*
+ * 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:
+ BIO_ADDR_free(tmpclient);
+ 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;
+}
+#endif
+
+static int dtls1_handshake_write(SSL *s)
+{
+ return dtls1_do_write(s, SSL3_RT_HANDSHAKE);
+}
+
+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;
+ }
- (void)BIO_dgram_get_peer(SSL_get_rbio(s), client);
+ /* 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,
+ (long)s->d1->mtu, NULL);
+ }
+ } else
+ return 0;
+ }
return 1;
}
-static void dtls1_set_handshake_header(SSL *s, int htype, unsigned long len)
+static size_t dtls1_link_min_mtu(void)
{
- 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 */
- dtls1_buffer_message(s, 0);
+ return (g_probable_mtu[(sizeof(g_probable_mtu) /
+ sizeof(g_probable_mtu[0])) - 1]);
}
-static int dtls1_handshake_write(SSL *s)
+size_t dtls1_min_mtu(SSL *s)
{
- return dtls1_do_write(s, SSL3_RT_HANDSHAKE);
+ 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;
}
projects / openssl.git / blobdiff