/* $OpenBSD: d1_pkt.c,v 1.123 2022/03/26 15:05:53 jsing Exp $ */
/*
* DTLS implementation written by Nagendra Modadugu
* (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
*/
/* ====================================================================
* Copyright (c) 1998-2005 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 (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* 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 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 acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS 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 AUTHOR OR 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.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.]
*/
#include <endian.h>
#include <errno.h>
#include <stdio.h>
#include <openssl/buffer.h>
#include <openssl/evp.h>
#include "bytestring.h"
#include "dtls_locl.h"
#include "pqueue.h"
#include "ssl_locl.h"
/* mod 128 saturating subtract of two 64-bit values in big-endian order */
static int
satsub64be(const unsigned char *v1, const unsigned char *v2)
{
int ret, sat, brw, i;
if (sizeof(long) == 8)
do {
long l;
if (BYTE_ORDER == LITTLE_ENDIAN)
break;
/* not reached on little-endians */
/* following test is redundant, because input is
* always aligned, but I take no chances... */
if (((size_t)v1 | (size_t)v2) & 0x7)
break;
l = *((long *)v1);
l -= *((long *)v2);
if (l > 128)
return 128;
else if (l<-128)
return -128;
else
return (int)l;
} while (0);
ret = (int)v1[7] - (int)v2[7];
sat = 0;
brw = ret >> 8; /* brw is either 0 or -1 */
if (ret & 0x80) {
for (i = 6; i >= 0; i--) {
brw += (int)v1[i]-(int)v2[i];
sat |= ~brw;
brw >>= 8;
}
} else {
for (i = 6; i >= 0; i--) {
brw += (int)v1[i]-(int)v2[i];
sat |= brw;
brw >>= 8;
}
}
brw <<= 8; /* brw is either 0 or -256 */
if (sat & 0xff)
return brw | 0x80;
else
return brw + (ret & 0xFF);
}
static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap,
const unsigned char *seq);
static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap,
const unsigned char *seq);
static DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD_INTERNAL *rr,
unsigned int *is_next_epoch);
static int dtls1_buffer_record(SSL *s, record_pqueue *q,
unsigned char *priority);
static int dtls1_process_record(SSL *s);
/* copy buffered record into SSL structure */
static int
dtls1_copy_record(SSL *s, DTLS1_RECORD_DATA_INTERNAL *rdata)
{
ssl3_release_buffer(&s->s3->rbuf);
s->internal->packet = rdata->packet;
s->internal->packet_length = rdata->packet_length;
memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER_INTERNAL));
memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD_INTERNAL));
return (1);
}
static int
dtls1_buffer_record(SSL *s, record_pqueue *queue, unsigned char *priority)
{
DTLS1_RECORD_DATA_INTERNAL *rdata;
pitem *item;
/* Limit the size of the queue to prevent DOS attacks */
if (pqueue_size(queue->q) >= 100)
return 0;
rdata = malloc(sizeof(DTLS1_RECORD_DATA_INTERNAL));
item = pitem_new(priority, rdata);
if (rdata == NULL || item == NULL)
goto init_err;
rdata->packet = s->internal->packet;
rdata->packet_length = s->internal->packet_length;
memcpy(&(rdata->rbuf), &(s->s3->rbuf), sizeof(SSL3_BUFFER_INTERNAL));
memcpy(&(rdata->rrec), &(s->s3->rrec), sizeof(SSL3_RECORD_INTERNAL));
item->data = rdata;
s->internal->packet = NULL;
s->internal->packet_length = 0;
memset(&(s->s3->rbuf), 0, sizeof(SSL3_BUFFER_INTERNAL));
memset(&(s->s3->rrec), 0, sizeof(SSL3_RECORD_INTERNAL));
if (!ssl3_setup_buffers(s))
goto err;
/* insert should not fail, since duplicates are dropped */
if (pqueue_insert(queue->q, item) == NULL)
goto err;
return (1);
err:
ssl3_release_buffer(&rdata->rbuf);
init_err:
SSLerror(s, ERR_R_INTERNAL_ERROR);
free(rdata);
pitem_free(item);
return (-1);
}
static int
dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue)
{
pitem *item;
item = pqueue_pop(queue->q);
if (item) {
dtls1_copy_record(s, item->data);
free(item->data);
pitem_free(item);
return (1);
}
return (0);
}
static int
dtls1_process_buffered_record(SSL *s)
{
/* Check if epoch is current. */
if (s->d1->unprocessed_rcds.epoch !=
tls12_record_layer_read_epoch(s->internal->rl))
return (0);
/* Update epoch once all unprocessed records have been processed. */
if (pqueue_peek(s->d1->unprocessed_rcds.q) == NULL) {
s->d1->unprocessed_rcds.epoch =
tls12_record_layer_read_epoch(s->internal->rl) + 1;
return (0);
}
/* Process one of the records. */
if (!dtls1_retrieve_buffered_record(s, &s->d1->unprocessed_rcds))
return (-1);
if (!dtls1_process_record(s))
return (-1);
return (1);
}
static int
dtls1_process_record(SSL *s)
{
SSL3_RECORD_INTERNAL *rr = &(s->s3->rrec);
uint8_t alert_desc;
uint8_t *out;
size_t out_len;
tls12_record_layer_set_version(s->internal->rl, s->version);
if (!tls12_record_layer_open_record(s->internal->rl, s->internal->packet,
s->internal->packet_length, &out, &out_len)) {
tls12_record_layer_alert(s->internal->rl, &alert_desc);
if (alert_desc == 0)
goto err;
/*
* DTLS should silently discard invalid records, including those
* with a bad MAC, as per RFC 6347 section 4.1.2.1.
*/
if (alert_desc == SSL_AD_BAD_RECORD_MAC) {
out_len = 0;
goto done;
}
if (alert_desc == SSL_AD_RECORD_OVERFLOW)
SSLerror(s, SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
goto fatal_err;
}
done:
rr->data = out;
rr->length = out_len;
rr->off = 0;
s->internal->packet_length = 0;
return (1);
fatal_err:
ssl3_send_alert(s, SSL3_AL_FATAL, alert_desc);
err:
return (0);
}
/* Call this to get a new input record.
* It will return <= 0 if more data is needed, normally due to an error
* or non-blocking IO.
* When it finishes, one packet has been decoded and can be found in
* ssl->s3->internal->rrec.type - is the type of record
* ssl->s3->internal->rrec.data, - data
* ssl->s3->internal->rrec.length, - number of bytes
*/
/* used only by dtls1_read_bytes */
int
dtls1_get_record(SSL *s)
{
SSL3_RECORD_INTERNAL *rr = &(s->s3->rrec);
unsigned char *p = NULL;
DTLS1_BITMAP *bitmap;
unsigned int is_next_epoch;
int ret, n;
/* See if there are pending records that can now be processed. */
if ((ret = dtls1_process_buffered_record(s)) != 0)
return (ret);
/* get something from the wire */
if (0) {
again:
/* dump this record on all retries */
rr->length = 0;
s->internal->packet_length = 0;
}
/* check if we have the header */
if ((s->internal->rstate != SSL_ST_READ_BODY) ||
(s->internal->packet_length < DTLS1_RT_HEADER_LENGTH)) {
CBS header, seq_no;
uint16_t epoch, len, ssl_version;
uint8_t type;
n = ssl3_packet_read(s, DTLS1_RT_HEADER_LENGTH);
if (n <= 0)
return (n);
/* If this packet contained a partial record, dump it. */
if (n != DTLS1_RT_HEADER_LENGTH)
goto again;
s->internal->rstate = SSL_ST_READ_BODY;
CBS_init(&header, s->internal->packet, s->internal->packet_length);
/* Pull apart the header into the DTLS1_RECORD */
if (!CBS_get_u8(&header, &type))
goto again;
if (!CBS_get_u16(&header, &ssl_version))
goto again;
/* Sequence number is 64 bits, with top 2 bytes = epoch. */
if (!CBS_get_bytes(&header, &seq_no, SSL3_SEQUENCE_SIZE))
goto again;
if (!CBS_get_u16(&seq_no, &epoch))
goto again;
if (!CBS_write_bytes(&seq_no, &rr->seq_num[2],
sizeof(rr->seq_num) - 2, NULL))
goto again;
if (!CBS_get_u16(&header, &len))
goto again;
rr->type = type;
rr->epoch = epoch;
rr->length = len;
/* unexpected version, silently discard */
if (!s->internal->first_packet && ssl_version != s->version)
goto again;
/* wrong version, silently discard record */
if ((ssl_version & 0xff00) != (s->version & 0xff00))
goto again;
/* record too long, silently discard it */
if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH)
goto again;
/* now s->internal->rstate == SSL_ST_READ_BODY */
p = (unsigned char *)CBS_data(&header);
}
/* s->internal->rstate == SSL_ST_READ_BODY, get and decode the data */
n = ssl3_packet_extend(s, DTLS1_RT_HEADER_LENGTH + rr->length);
if (n <= 0)
return (n);
/* If this packet contained a partial record, dump it. */
if (n != DTLS1_RT_HEADER_LENGTH + rr->length)
goto again;
s->internal->rstate = SSL_ST_READ_HEADER; /* set state for later operations */
/* match epochs. NULL means the packet is dropped on the floor */
bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch);
if (bitmap == NULL)
goto again;
/*
* Check whether this is a repeat, or aged record.
* Don't check if we're listening and this message is
* a ClientHello. They can look as if they're replayed,
* since they arrive from different connections and
* would be dropped unnecessarily.
*/
if (!(s->d1->listen && rr->type == SSL3_RT_HANDSHAKE &&
p != NULL && *p == SSL3_MT_CLIENT_HELLO) &&
!dtls1_record_replay_check(s, bitmap, rr->seq_num))
goto again;
/* just read a 0 length packet */
if (rr->length == 0)
goto again;
/* If this record is from the next epoch (either HM or ALERT),
* and a handshake is currently in progress, buffer it since it
* cannot be processed at this time. However, do not buffer
* anything while listening.
*/
if (is_next_epoch) {
if ((SSL_in_init(s) || s->internal->in_handshake) && !s->d1->listen) {
if (dtls1_buffer_record(s, &(s->d1->unprocessed_rcds),
rr->seq_num) < 0)
return (-1);
/* Mark receipt of record. */
dtls1_record_bitmap_update(s, bitmap, rr->seq_num);
}
goto again;
}
if (!dtls1_process_record(s))
goto again;
/* Mark receipt of record. */
dtls1_record_bitmap_update(s, bitmap, rr->seq_num);
return (1);
}
static int
dtls1_read_handshake_unexpected(SSL *s)
{
SSL3_RECORD_INTERNAL *rr = &s->s3->rrec;
struct hm_header_st hs_msg_hdr;
CBS cbs;
int ret;
if (s->internal->in_handshake) {
SSLerror(s, ERR_R_INTERNAL_ERROR);
return -1;
}
if (rr->off != 0) {
SSLerror(s, ERR_R_INTERNAL_ERROR);
return -1;
}
/* Parse handshake message header. */
CBS_init(&cbs, rr->data, rr->length);
if (!dtls1_get_message_header(&cbs, &hs_msg_hdr))
return -1; /* XXX - probably should drop/continue. */
/* This may just be a stale retransmit. */
if (rr->epoch != tls12_record_layer_read_epoch(s->internal->rl)) {
rr->length = 0;
return 1;
}
if (hs_msg_hdr.type == SSL3_MT_HELLO_REQUEST) {
/*
* Incoming HelloRequest messages should only be received by a
* client. A server may send these at any time - a client should
* ignore the message if received in the middle of a handshake.
* See RFC 5246 sections 7.4 and 7.4.1.1.
*/
if (s->server) {
SSLerror(s, SSL_R_UNEXPECTED_MESSAGE);
ssl3_send_alert(s, SSL3_AL_FATAL,
SSL_AD_UNEXPECTED_MESSAGE);
return -1;
}
/* XXX - should also check frag offset/length. */
if (hs_msg_hdr.msg_len != 0) {
SSLerror(s, SSL_R_BAD_HELLO_REQUEST);
ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
return -1;
}
ssl_msg_callback(s, 0, SSL3_RT_HANDSHAKE, rr->data,
DTLS1_HM_HEADER_LENGTH);
rr->length = 0;
/*
* It should be impossible to hit this, but keep the safety
* harness for now...
*/
if (s->session == NULL || s->session->cipher == NULL)
return 1;
/*
* Ignore this message if we're currently handshaking,
* renegotiation is already pending or renegotiation is disabled
* via flags.
*/
if (!SSL_is_init_finished(s) || s->s3->renegotiate ||
(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) != 0)
return 1;
s->d1->handshake_read_seq++;
/* XXX - why is this set here but not in ssl3? */
s->internal->new_session = 1;
if (!ssl3_renegotiate(s))
return 1;
if (!ssl3_renegotiate_check(s))
return 1;
} else if (hs_msg_hdr.type == SSL3_MT_CLIENT_HELLO) {
/*
* Incoming ClientHello messages should only be received by a
* server. A client may send these in response to server
* initiated renegotiation (HelloRequest) or in order to
* initiate renegotiation by the client. See RFC 5246 section
* 7.4.1.2.
*/
if (!s->server) {
SSLerror(s, SSL_R_UNEXPECTED_MESSAGE);
ssl3_send_alert(s, SSL3_AL_FATAL,
SSL_AD_UNEXPECTED_MESSAGE);
return -1;
}
/*
* A client should not be sending a ClientHello unless we're not
* currently handshaking.
*/
if (!SSL_is_init_finished(s)) {
SSLerror(s, SSL_R_UNEXPECTED_MESSAGE);
ssl3_send_alert(s, SSL3_AL_FATAL,
SSL_AD_UNEXPECTED_MESSAGE);
return -1;
}
if ((s->internal->options & SSL_OP_NO_CLIENT_RENEGOTIATION) != 0) {
ssl3_send_alert(s, SSL3_AL_FATAL,
SSL_AD_NO_RENEGOTIATION);
return -1;
}
if (s->session == NULL || s->session->cipher == NULL) {
SSLerror(s, ERR_R_INTERNAL_ERROR);
return -1;
}
/* Client requested renegotiation but it is not permitted. */
if (!s->s3->send_connection_binding ||
(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) != 0) {
ssl3_send_alert(s, SSL3_AL_WARNING,
SSL_AD_NO_RENEGOTIATION);
return 1;
}
s->s3->hs.state = SSL_ST_ACCEPT;
s->internal->renegotiate = 1;
s->internal->new_session = 1;
} else if (hs_msg_hdr.type == SSL3_MT_FINISHED && s->server) {
/*
* If we are server, we may have a repeated FINISHED of the
* client here, then retransmit our CCS and FINISHED.
*/
if (dtls1_check_timeout_num(s) < 0)
return -1;
/* XXX - should this be calling ssl_msg_callback()? */
dtls1_retransmit_buffered_messages(s);
rr->length = 0;
return 1;
} else {
SSLerror(s, SSL_R_UNEXPECTED_MESSAGE);
ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE);
return -1;
}
if ((ret = s->internal->handshake_func(s)) < 0)
return ret;
if (ret == 0) {
SSLerror(s, SSL_R_SSL_HANDSHAKE_FAILURE);
return -1;
}
if (!(s->internal->mode & SSL_MODE_AUTO_RETRY)) {
if (s->s3->rbuf.left == 0) {
ssl_force_want_read(s);
return -1;
}
}
/*
* We either finished a handshake or ignored the request, now try again
* to obtain the (application) data we were asked for.
*/
return 1;
}
/* Return up to 'len' payload bytes received in 'type' records.
* 'type' is one of the following:
*
* - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
* - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
* - 0 (during a shutdown, no data has to be returned)
*
* If we don't have stored data to work from, read a SSL/TLS record first
* (possibly multiple records if we still don't have anything to return).
*
* This function must handle any surprises the peer may have for us, such as
* Alert records (e.g. close_notify), ChangeCipherSpec records (not really
* a surprise, but handled as if it were), or renegotiation requests.
* Also if record payloads contain fragments too small to process, we store
* them until there is enough for the respective protocol (the record protocol
* may use arbitrary fragmentation and even interleaving):
* Change cipher spec protocol
* just 1 byte needed, no need for keeping anything stored
* Alert protocol
* 2 bytes needed (AlertLevel, AlertDescription)
* Handshake protocol
* 4 bytes needed (HandshakeType, uint24 length) -- we just have
* to detect unexpected Client Hello and Hello Request messages
* here, anything else is handled by higher layers
* Application data protocol
* none of our business
*/
int
dtls1_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
{
SSL3_RECORD_INTERNAL *rr;
int rrcount = 0;
unsigned int n;
int ret;
if (s->s3->rbuf.buf == NULL) {
if (!ssl3_setup_buffers(s))
return -1;
}
if (len < 0) {
SSLerror(s, ERR_R_INTERNAL_ERROR);
return -1;
}
if (type != 0 && type != SSL3_RT_APPLICATION_DATA &&
type != SSL3_RT_HANDSHAKE) {
SSLerror(s, ERR_R_INTERNAL_ERROR);
return -1;
}
if (peek && type != SSL3_RT_APPLICATION_DATA) {
SSLerror(s, ERR_R_INTERNAL_ERROR);
return -1;
}
if (SSL_in_init(s) && !s->internal->in_handshake) {
if ((ret = s->internal->handshake_func(s)) < 0)
return ret;
if (ret == 0) {
SSLerror(s, SSL_R_SSL_HANDSHAKE_FAILURE);
return -1;
}
}
start:
/*
* Do not process more than three consecutive records, otherwise the
* peer can cause us to loop indefinitely. Instead, return with an
* SSL_ERROR_WANT_READ so the caller can choose when to handle further
* processing. In the future, the total number of non-handshake and
* non-application data records per connection should probably also be
* limited...
*/
if (rrcount++ >= 3) {
ssl_force_want_read(s);
return -1;
}
s->internal->rwstate = SSL_NOTHING;
rr = &s->s3->rrec;
/*
* We are not handshaking and have no data yet, so process data buffered
* during the last handshake in advance, if any.
*/
if (s->s3->hs.state == SSL_ST_OK && rr->length == 0)
dtls1_retrieve_buffered_record(s, &s->d1->buffered_app_data);
if (dtls1_handle_timeout(s) > 0)
goto start;
if (rr->length == 0 || s->internal->rstate == SSL_ST_READ_BODY) {
if ((ret = dtls1_get_record(s)) <= 0) {
/* Anything other than a timeout is an error. */
if ((ret = dtls1_read_failed(s, ret)) <= 0)
return ret;
goto start;
}
}
if (s->d1->listen && rr->type != SSL3_RT_HANDSHAKE) {
rr->length = 0;
goto start;
}
/* We now have a packet which can be read and processed. */
if (s->s3->change_cipher_spec && rr->type != SSL3_RT_HANDSHAKE) {
/*
* We now have application data between CCS and Finished.
* Most likely the packets were reordered on their way, so
* buffer the application data for later processing rather
* than dropping the connection.
*/
if (dtls1_buffer_record(s, &s->d1->buffered_app_data,
rr->seq_num) < 0) {
SSLerror(s, ERR_R_INTERNAL_ERROR);
return (-1);
}
rr->length = 0;
goto start;
}
/*
* If the other end has shut down, throw anything we read away (even in
* 'peek' mode).
*/
if (s->internal->shutdown & SSL_RECEIVED_SHUTDOWN) {
s->internal->rwstate = SSL_NOTHING;
rr->length = 0;
return 0;
}
/* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
if (type == rr->type) {
/*
* Make sure that we are not getting application data when we
* are doing a handshake for the first time.
*/
if (SSL_in_init(s) && type == SSL3_RT_APPLICATION_DATA &&
!tls12_record_layer_read_protected(s->internal->rl)) {
SSLerror(s, SSL_R_APP_DATA_IN_HANDSHAKE);
ssl3_send_alert(s, SSL3_AL_FATAL,
SSL_AD_UNEXPECTED_MESSAGE);
return -1;
}
if (len <= 0)
return len;
if ((unsigned int)len > rr->length)
n = rr->length;
else
n = (unsigned int)len;
memcpy(buf, &rr->data[rr->off], n);
if (!peek) {
memset(&rr->data[rr->off], 0, n);
rr->length -= n;
rr->off += n;
if (rr->length == 0) {
s->internal->rstate = SSL_ST_READ_HEADER;
rr->off = 0;
}
}
return n;
}
/*
* If we get here, then type != rr->type; if we have a handshake
* message, then it was unexpected (Hello Request or Client Hello).
*/
if (rr->type == SSL3_RT_ALERT) {
if ((ret = ssl3_read_alert(s)) <= 0)
return ret;
goto start;
}
if (s->internal->shutdown & SSL_SENT_SHUTDOWN) {
s->internal->rwstate = SSL_NOTHING;
rr->length = 0;
return (0);
}
if (rr->type == SSL3_RT_APPLICATION_DATA) {
/*
* At this point, we were expecting handshake data, but have
* application data. If the library was running inside
* ssl3_read() (i.e. in_read_app_data is set) and it makes
* sense to read application data at this point (session
* renegotiation not yet started), we will indulge it.
*/
if (s->s3->in_read_app_data != 0 &&
s->s3->total_renegotiations != 0 &&
(((s->s3->hs.state & SSL_ST_CONNECT) &&
(s->s3->hs.state >= SSL3_ST_CW_CLNT_HELLO_A) &&
(s->s3->hs.state <= SSL3_ST_CR_SRVR_HELLO_A)) || (
(s->s3->hs.state & SSL_ST_ACCEPT) &&
(s->s3->hs.state <= SSL3_ST_SW_HELLO_REQ_A) &&
(s->s3->hs.state >= SSL3_ST_SR_CLNT_HELLO_A)))) {
s->s3->in_read_app_data = 2;
return -1;
} else {
SSLerror(s, SSL_R_UNEXPECTED_RECORD);
ssl3_send_alert(s, SSL3_AL_FATAL,
SSL_AD_UNEXPECTED_MESSAGE);
return -1;
}
}
if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) {
if ((ret = ssl3_read_change_cipher_spec(s)) <= 0)
return ret;
goto start;
}
if (rr->type == SSL3_RT_HANDSHAKE) {
if ((ret = dtls1_read_handshake_unexpected(s)) <= 0)
return ret;
goto start;
}
/* Unknown record type. */
SSLerror(s, SSL_R_UNEXPECTED_RECORD);
ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE);
return -1;
}
int
dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len)
{
int i;
if (SSL_in_init(s) && !s->internal->in_handshake)
{
i = s->internal->handshake_func(s);
if (i < 0)
return (i);
if (i == 0) {
SSLerror(s, SSL_R_SSL_HANDSHAKE_FAILURE);
return -1;
}
}
if (len > SSL3_RT_MAX_PLAIN_LENGTH) {
SSLerror(s, SSL_R_DTLS_MESSAGE_TOO_BIG);
return -1;
}
i = dtls1_write_bytes(s, type, buf_, len);
return i;
}
/* Call this to write data in records of type 'type'
* It will return <= 0 if not all data has been sent or non-blocking IO.
*/
int
dtls1_write_bytes(SSL *s, int type, const void *buf, int len)
{
int i;
OPENSSL_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH);
s->internal->rwstate = SSL_NOTHING;
i = do_dtls1_write(s, type, buf, len);
return i;
}
int
do_dtls1_write(SSL *s, int type, const unsigned char *buf, unsigned int len)
{
SSL3_BUFFER_INTERNAL *wb = &(s->s3->wbuf);
size_t out_len;
CBB cbb;
int ret;
memset(&cbb, 0, sizeof(cbb));
/*
* First check if there is a SSL3_BUFFER_INTERNAL still being written
* out. This will happen with non blocking IO.
*/
if (wb->left != 0) {
OPENSSL_assert(0); /* XDTLS: want to see if we ever get here */
return (ssl3_write_pending(s, type, buf, len));
}
/* If we have an alert to send, let's send it */
if (s->s3->alert_dispatch) {
if ((ret = ssl3_dispatch_alert(s)) <= 0)
return (ret);
/* If it went, fall through and send more stuff. */
}
if (len == 0)
return 0;
wb->offset = 0;
if (!CBB_init_fixed(&cbb, wb->buf, wb->len))
goto err;
tls12_record_layer_set_version(s->internal->rl, s->version);
if (!tls12_record_layer_seal_record(s->internal->rl, type, buf, len, &cbb))
goto err;
if (!CBB_finish(&cbb, NULL, &out_len))
goto err;
wb->left = out_len;
/*
* Memorize arguments so that ssl3_write_pending can detect
* bad write retries later.
*/
s->s3->wpend_tot = len;
s->s3->wpend_buf = buf;
s->s3->wpend_type = type;
s->s3->wpend_ret = len;
/* We now just need to write the buffer. */
return ssl3_write_pending(s, type, buf, len);
err:
CBB_cleanup(&cbb);
return -1;
}
static int
dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap,
const unsigned char *seq)
{
unsigned int shift;
int cmp;
cmp = satsub64be(seq, bitmap->max_seq_num);
if (cmp > 0)
return 1; /* this record in new */
shift = -cmp;
if (shift >= sizeof(bitmap->map)*8)
return 0; /* stale, outside the window */
else if (bitmap->map & (1UL << shift))
return 0; /* record previously received */
return 1;
}
static void
dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap,
const unsigned char *seq)
{
unsigned int shift;
int cmp;
cmp = satsub64be(seq, bitmap->max_seq_num);
if (cmp > 0) {
shift = cmp;
if (shift < sizeof(bitmap->map)*8)
bitmap->map <<= shift, bitmap->map |= 1UL;
else
bitmap->map = 1UL;
memcpy(bitmap->max_seq_num, seq, 8);
} else {
shift = -cmp;
if (shift < sizeof(bitmap->map) * 8)
bitmap->map |= 1UL << shift;
}
}
static DTLS1_BITMAP *
dtls1_get_bitmap(SSL *s, SSL3_RECORD_INTERNAL *rr, unsigned int *is_next_epoch)
{
uint16_t read_epoch, read_epoch_next;
*is_next_epoch = 0;
read_epoch = tls12_record_layer_read_epoch(s->internal->rl);
read_epoch_next = read_epoch + 1;
/* In current epoch, accept HM, CCS, DATA, & ALERT */
if (rr->epoch == read_epoch)
return &s->d1->bitmap;
/* Only HM and ALERT messages can be from the next epoch */
if (rr->epoch == read_epoch_next &&
(rr->type == SSL3_RT_HANDSHAKE || rr->type == SSL3_RT_ALERT)) {
*is_next_epoch = 1;
return &s->d1->next_bitmap;
}
return NULL;
}
void
dtls1_reset_read_seq_numbers(SSL *s)
{
memcpy(&(s->d1->bitmap), &(s->d1->next_bitmap), sizeof(DTLS1_BITMAP));
memset(&(s->d1->next_bitmap), 0, sizeof(DTLS1_BITMAP));
}