Rename record layer source files

Reviewed-by: Richard Levitte <levitte@openssl.org>

1 files changed, 1323 insertions, 0 deletions

diff --git a/ssl/record/rec_layer_d1.c b/ssl/record/rec_layer_d1.c
new file mode 100644
index 0000000000..bd3c0e8f3d
--- /dev/null
+++ b/ssl/record/rec_layer_d1.c
@@ -0,0 +1,1323 @@
+/* ssl/record/rec_layer_d1.c */
+/*
+ * 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 <stdio.h>
+#include <errno.h>
+#define USE_SOCKETS
+#include "../ssl_locl.h"
+#include <openssl/evp.h>
+#include <openssl/buffer.h>
+#include <openssl/pqueue.h>
+#include <openssl/rand.h>
+#include "record_locl.h"
+
+int DTLS_RECORD_LAYER_new(RECORD_LAYER *rl)
+{
+    DTLS_RECORD_LAYER *d;
+    
+    if ((d = OPENSSL_malloc(sizeof *d)) == NULL) {
+        return (0);
+    }
+
+
+    rl->d = d;
+
+    d->unprocessed_rcds.q = pqueue_new();
+    d->processed_rcds.q = pqueue_new();
+    d->buffered_app_data.q = pqueue_new();
+
+    if (!d->unprocessed_rcds.q || !d->processed_rcds.q
+        || !d->buffered_app_data.q) {
+        if (d->unprocessed_rcds.q)
+            pqueue_free(d->unprocessed_rcds.q);
+        if (d->processed_rcds.q)
+            pqueue_free(d->processed_rcds.q);
+        if (d->buffered_app_data.q)
+            pqueue_free(d->buffered_app_data.q);
+        OPENSSL_free(d);
+        rl->d = NULL;
+        return (0);
+    }
+
+    return 1;
+}
+
+void DTLS_RECORD_LAYER_free(RECORD_LAYER *rl)
+{
+    DTLS_RECORD_LAYER_clear(rl);
+    pqueue_free(rl->d->unprocessed_rcds.q);
+    pqueue_free(rl->d->processed_rcds.q);
+    pqueue_free(rl->d->buffered_app_data.q);
+    OPENSSL_free(rl->d);
+    rl->d = NULL;
+}
+
+void DTLS_RECORD_LAYER_clear(RECORD_LAYER *rl)
+{
+    DTLS_RECORD_LAYER *d;
+    pitem *item = NULL;
+    DTLS1_RECORD_DATA *rdata;
+    pqueue unprocessed_rcds;
+    pqueue processed_rcds;
+    pqueue buffered_app_data;
+
+    d = rl->d;
+    
+    while ((item = pqueue_pop(d->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(d->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(d->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);
+    }
+
+    unprocessed_rcds = d->unprocessed_rcds.q;
+    processed_rcds = d->processed_rcds.q;
+    buffered_app_data = d->buffered_app_data.q;
+    memset(d, 0, sizeof *d);
+    d->unprocessed_rcds.q = unprocessed_rcds;
+    d->processed_rcds.q = processed_rcds;
+    d->buffered_app_data.q = buffered_app_data;
+}
+
+void DTLS_RECORD_LAYER_set_saved_w_epoch(RECORD_LAYER *rl, unsigned short e)
+{
+    if (e == rl->d->w_epoch - 1) {
+        memcpy(rl->d->curr_write_sequence,
+               rl->write_sequence,
+               sizeof(rl->write_sequence));
+        memcpy(rl->write_sequence,
+               rl->d->last_write_sequence,
+               sizeof(rl->write_sequence));
+    } else if (e == rl->d->w_epoch + 1) {
+        memcpy(rl->d->last_write_sequence,
+               rl->write_sequence,
+               sizeof(unsigned char[8]));
+        memcpy(rl->write_sequence,
+               rl->d->curr_write_sequence,
+               sizeof(rl->write_sequence));
+    }
+    rl->d->w_epoch = e;
+}
+
+void DTLS_RECORD_LAYER_resync_write(RECORD_LAYER *rl)
+{
+    memcpy(rl->write_sequence, rl->read_sequence, sizeof(rl->write_sequence));
+}
+
+static int have_handshake_fragment(SSL *s, int type, unsigned char *buf,
+                                   int len, int peek);
+
+/* copy buffered record into SSL structure */
+static int dtls1_copy_record(SSL *s, pitem *item)
+{
+    DTLS1_RECORD_DATA *rdata;
+
+    rdata = (DTLS1_RECORD_DATA *)item->data;
+
+    SSL3_BUFFER_release(&s->rlayer.rbuf);
+
+    s->rlayer.packet = rdata->packet;
+    s->rlayer.packet_length = rdata->packet_length;
+    memcpy(&s->rlayer.rbuf, &(rdata->rbuf), sizeof(SSL3_BUFFER));
+    memcpy(&s->rlayer.rrec, &(rdata->rrec), sizeof(SSL3_RECORD));
+
+    /* Set proper sequence number for mac calculation */
+    memcpy(&(s->rlayer.read_sequence[2]), &(rdata->packet[5]), 6);
+
+    return (1);
+}
+
+int
+dtls1_buffer_record(SSL *s, record_pqueue *queue, unsigned char *priority)
+{
+    DTLS1_RECORD_DATA *rdata;
+    pitem *item;
+
+    /* Limit the size of the queue to prevent DOS attacks */
+    if (pqueue_size(queue->q) >= 100)
+        return 0;
+
+    rdata = OPENSSL_malloc(sizeof(DTLS1_RECORD_DATA));
+    item = pitem_new(priority, rdata);
+    if (rdata == NULL || item == NULL) {
+        if (rdata != NULL)
+            OPENSSL_free(rdata);
+        if (item != NULL)
+            pitem_free(item);
+
+        SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
+        return -1;
+    }
+
+    rdata->packet = s->rlayer.packet;
+    rdata->packet_length = s->rlayer.packet_length;
+    memcpy(&(rdata->rbuf), &s->rlayer.rbuf, sizeof(SSL3_BUFFER));
+    memcpy(&(rdata->rrec), &s->rlayer.rrec, sizeof(SSL3_RECORD));
+
+    item->data = rdata;
+
+#ifndef OPENSSL_NO_SCTP
+    /* Store bio_dgram_sctp_rcvinfo struct */
+    if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
+        (s->state == SSL3_ST_SR_FINISHED_A
+         || s->state == SSL3_ST_CR_FINISHED_A)) {
+        BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_GET_RCVINFO,
+                 sizeof(rdata->recordinfo), &rdata->recordinfo);
+    }
+#endif
+
+    s->rlayer.packet = NULL;
+    s->rlayer.packet_length = 0;
+    memset(&s->rlayer.rbuf, 0, sizeof(SSL3_BUFFER));
+    memset(&s->rlayer.rrec, 0, sizeof(SSL3_RECORD));
+
+    if (!ssl3_setup_buffers(s)) {
+        SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
+        if (rdata->rbuf.buf != NULL)
+            OPENSSL_free(rdata->rbuf.buf);
+        OPENSSL_free(rdata);
+        pitem_free(item);
+        return (-1);
+    }
+
+    /* insert should not fail, since duplicates are dropped */
+    if (pqueue_insert(queue->q, item) == NULL) {
+        SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
+        if (rdata->rbuf.buf != NULL)
+            OPENSSL_free(rdata->rbuf.buf);
+        OPENSSL_free(rdata);
+        pitem_free(item);
+        return (-1);
+    }
+
+    return (1);
+}
+
+int dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue)
+{
+    pitem *item;
+
+    item = pqueue_pop(queue->q);
+    if (item) {
+        dtls1_copy_record(s, item);
+
+        OPENSSL_free(item->data);
+        pitem_free(item);
+
+        return (1);
+    }
+
+    return (0);
+}
+
+/*
+ * retrieve a buffered record that belongs to the new epoch, i.e., not
+ * processed yet
+ */
+#define dtls1_get_unprocessed_record(s) \
+                   dtls1_retrieve_buffered_record((s), \
+                   &((s)->rlayer.d->unprocessed_rcds))
+
+
+int dtls1_process_buffered_records(SSL *s)
+{
+    pitem *item;
+
+    item = pqueue_peek(s->rlayer.d->unprocessed_rcds.q);
+    if (item) {
+        /* Check if epoch is current. */
+        if (s->rlayer.d->unprocessed_rcds.epoch != s->rlayer.d->r_epoch)
+            return (1);         /* Nothing to do. */
+
+        /* Process all the records. */
+        while (pqueue_peek(s->rlayer.d->unprocessed_rcds.q)) {
+            dtls1_get_unprocessed_record(s);
+            if (!dtls1_process_record(s))
+                return (0);
+            if (dtls1_buffer_record(s, &(s->rlayer.d->processed_rcds),
+                SSL3_RECORD_get_seq_num(&s->rlayer.rrec)) < 0)
+                return -1;
+        }
+    }
+
+    /*
+     * sync epoch numbers once all the unprocessed records have been
+     * processed
+     */
+    s->rlayer.d->processed_rcds.epoch = s->rlayer.d->r_epoch;
+    s->rlayer.d->unprocessed_rcds.epoch = s->rlayer.d->r_epoch + 1;
+
+    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)
+{
+    int al, i, j, ret;
+    unsigned int n;
+    SSL3_RECORD *rr;
+    void (*cb) (const SSL *ssl, int type2, int val) = NULL;
+
+    if (!SSL3_BUFFER_is_initialised(&s->rlayer.rbuf)) {
+        /* Not initialized yet */
+        if (!ssl3_setup_buffers(s))
+            return (-1);
+    }
+
+    if ((type && (type != SSL3_RT_APPLICATION_DATA) &&
+         (type != SSL3_RT_HANDSHAKE)) ||
+        (peek && (type != SSL3_RT_APPLICATION_DATA))) {
+        SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
+        return -1;
+    }
+
+    /*
+     * check whether there's a handshake message (client hello?) waiting
+     */
+    if ((ret = have_handshake_fragment(s, type, buf, len, peek)))
+        return ret;
+
+    /*
+     * Now s->rlayer.d->handshake_fragment_len == 0 if
+     * type == SSL3_RT_HANDSHAKE.
+     */
+
+#ifndef OPENSSL_NO_SCTP
+    /*
+     * Continue handshake if it had to be interrupted to read app data with
+     * SCTP.
+     */
+    if ((!s->in_handshake && SSL_in_init(s)) ||
+        (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
+         (s->state == DTLS1_SCTP_ST_SR_READ_SOCK
+          || s->state == DTLS1_SCTP_ST_CR_READ_SOCK)
+         && s->s3->in_read_app_data != 2))
+#else
+    if (!s->in_handshake && SSL_in_init(s))
+#endif
+    {
+        /* type == SSL3_RT_APPLICATION_DATA */
+        i = s->handshake_func(s);
+        if (i < 0)
+            return (i);
+        if (i == 0) {
+            SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
+            return (-1);
+        }
+    }
+
+ start:
+    s->rwstate = SSL_NOTHING;
+
+    /*-
+     * s->s3->rrec.type         - is the type of record
+     * s->s3->rrec.data,    - data
+     * s->s3->rrec.off,     - offset into 'data' for next read
+     * s->s3->rrec.length,  - number of bytes.
+     */
+    rr = &s->rlayer.rrec;
+
+    /*
+     * We are not handshaking and have no data yet, so process data buffered
+     * during the last handshake in advance, if any.
+     */
+    if (s->state == SSL_ST_OK && rr->length == 0) {
+        pitem *item;
+        item = pqueue_pop(s->rlayer.d->buffered_app_data.q);
+        if (item) {
+#ifndef OPENSSL_NO_SCTP
+            /* Restore bio_dgram_sctp_rcvinfo struct */
+            if (BIO_dgram_is_sctp(SSL_get_rbio(s))) {
+                DTLS1_RECORD_DATA *rdata = (DTLS1_RECORD_DATA *)item->data;
+                BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_SET_RCVINFO,
+                         sizeof(rdata->recordinfo), &rdata->recordinfo);
+            }
+#endif
+
+            dtls1_copy_record(s, item);
+
+            OPENSSL_free(item->data);
+            pitem_free(item);
+        }
+    }
+
+    /* Check for timeout */
+    if (dtls1_handle_timeout(s) > 0)
+        goto start;
+
+    /* get new packet if necessary */
+    if ((rr->length == 0) || (s->rlayer.rstate == SSL_ST_READ_BODY)) {
+        ret = dtls1_get_record(s);
+        if (ret <= 0) {
+            ret = dtls1_read_failed(s, ret);
+            /* anything other than a timeout is an error */
+            if (ret <= 0)
+                return (ret);
+            else
+                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 /* set when we receive ChangeCipherSpec,
+                                   * reset by ssl3_get_finished */
+        && (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->rlayer.d->buffered_app_data),
+            rr->seq_num) < 0) {
+            SSLerr(SSL_F_DTLS1_READ_BYTES, 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->shutdown & SSL_RECEIVED_SHUTDOWN) {
+        rr->length = 0;
+        s->rwstate = SSL_NOTHING;
+        return (0);
+    }
+
+    if (type == rr->type) {     /* SSL3_RT_APPLICATION_DATA or
+                                 * SSL3_RT_HANDSHAKE */
+        /*
+         * 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) &&
+            (s->enc_read_ctx == NULL)) {
+            al = SSL_AD_UNEXPECTED_MESSAGE;
+            SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_APP_DATA_IN_HANDSHAKE);
+            goto f_err;
+        }
+
+        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) {
+            rr->length -= n;
+            rr->off += n;
+            if (rr->length == 0) {
+                s->rlayer.rstate = SSL_ST_READ_HEADER;
+                rr->off = 0;
+            }
+        }
+#ifndef OPENSSL_NO_SCTP
+        /*
+         * We were about to renegotiate but had to read belated application
+         * data first, so retry.
+         */
+        if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
+            rr->type == SSL3_RT_APPLICATION_DATA &&
+            (s->state == DTLS1_SCTP_ST_SR_READ_SOCK
+             || s->state == DTLS1_SCTP_ST_CR_READ_SOCK)) {
+            s->rwstate = SSL_READING;
+            BIO_clear_retry_flags(SSL_get_rbio(s));
+            BIO_set_retry_read(SSL_get_rbio(s));
+        }
+
+        /*
+         * We might had to delay a close_notify alert because of reordered
+         * app data. If there was an alert and there is no message to read
+         * anymore, finally set shutdown.
+         */
+        if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
+            s->d1->shutdown_received
+            && !BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) {
+            s->shutdown |= SSL_RECEIVED_SHUTDOWN;
+            return (0);
+        }
+#endif
+        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).
+     */
+
+    /*
+     * In case of record types for which we have 'fragment' storage, fill
+     * that so that we can process the data at a fixed place.
+     */
+    {
+        unsigned int k, dest_maxlen = 0;
+        unsigned char *dest = NULL;
+        unsigned int *dest_len = NULL;
+
+        if (rr->type == SSL3_RT_HANDSHAKE) {
+            dest_maxlen = sizeof s->rlayer.d->handshake_fragment;
+            dest = s->rlayer.d->handshake_fragment;
+            dest_len = &s->rlayer.d->handshake_fragment_len;
+        } else if (rr->type == SSL3_RT_ALERT) {
+            dest_maxlen = sizeof(s->rlayer.d->alert_fragment);
+            dest = s->rlayer.d->alert_fragment;
+            dest_len = &s->rlayer.d->alert_fragment_len;
+        }
+#ifndef OPENSSL_NO_HEARTBEATS
+        else if (rr->type == TLS1_RT_HEARTBEAT) {
+            /* We allow a 0 return */
+            if(dtls1_process_heartbeat(s, SSL3_RECORD_get_data(&s->rlayer.rrec),
+                    SSL3_RECORD_get_length(&s->rlayer.rrec)) < 0) {
+                return -1;
+            }
+            /* Exit and notify application to read again */
+            rr->length = 0;
+            s->rwstate = SSL_READING;
+            BIO_clear_retry_flags(SSL_get_rbio(s));
+            BIO_set_retry_read(SSL_get_rbio(s));
+            return (-1);
+        }
+#endif
+        /* else it's a CCS message, or application data or wrong */
+        else if (rr->type != SSL3_RT_CHANGE_CIPHER_SPEC) {
+            /*
+             * Application data while renegotiating is allowed. Try again
+             * reading.
+             */
+            if (rr->type == SSL3_RT_APPLICATION_DATA) {
+                BIO *bio;
+                s->s3->in_read_app_data = 2;
+                bio = SSL_get_rbio(s);
+                s->rwstate = SSL_READING;
+                BIO_clear_retry_flags(bio);
+                BIO_set_retry_read(bio);
+                return (-1);
+            }
+
+            /* Not certain if this is the right error handling */
+            al = SSL_AD_UNEXPECTED_MESSAGE;
+            SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
+            goto f_err;
+        }
+
+        if (dest_maxlen > 0) {
+            /*
+             * XDTLS: In a pathalogical case, the Client Hello may be
+             * fragmented--don't always expect dest_maxlen bytes
+             */
+            if (rr->length < dest_maxlen) {
+#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
+                /*
+                 * for normal alerts rr->length is 2, while
+                 * dest_maxlen is 7 if we were to handle this
+                 * non-existing alert...
+                 */
+                FIX ME
+#endif
+                 s->rlayer.rstate = SSL_ST_READ_HEADER;
+                rr->length = 0;
+                goto start;
+            }
+
+            /* now move 'n' bytes: */
+            for (k = 0; k < dest_maxlen; k++) {
+                dest[k] = rr->data[rr->off++];
+                rr->length--;
+            }
+            *dest_len = dest_maxlen;
+        }
+    }
+
+    /*-
+     * s->rlayer.d->handshake_fragment_len == 12  iff  rr->type == SSL3_RT_HANDSHAKE;
+     * s->rlayer.d->alert_fragment_len == 7      iff  rr->type == SSL3_RT_ALERT.
+     * (Possibly rr is 'empty' now, i.e. rr->length may be 0.)
+     */
+
+    /* If we are a client, check for an incoming 'Hello Request': */
+    if ((!s->server) &&
+        (s->rlayer.d->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
+        (s->rlayer.d->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
+        (s->session != NULL) && (s->session->cipher != NULL)) {
+        s->rlayer.d->handshake_fragment_len = 0;
+
+        if ((s->rlayer.d->handshake_fragment[1] != 0) ||
+            (s->rlayer.d->handshake_fragment[2] != 0) ||
+            (s->rlayer.d->handshake_fragment[3] != 0)) {
+            al = SSL_AD_DECODE_ERROR;
+            SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_BAD_HELLO_REQUEST);
+            goto err;
+        }
+
+        /*
+         * no need to check sequence number on HELLO REQUEST messages
+         */
+
+        if (s->msg_callback)
+            s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
+                            s->rlayer.d->handshake_fragment, 4, s,
+                            s->msg_callback_arg);
+
+        if (SSL_is_init_finished(s) &&
+            !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
+            !s->s3->renegotiate) {
+            s->d1->handshake_read_seq++;
+            s->new_session = 1;
+            ssl3_renegotiate(s);
+            if (ssl3_renegotiate_check(s)) {
+                i = s->handshake_func(s);
+                if (i < 0)
+                    return (i);
+                if (i == 0) {
+                    SSLerr(SSL_F_DTLS1_READ_BYTES,
+                           SSL_R_SSL_HANDSHAKE_FAILURE);
+                    return (-1);
+                }
+
+                if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
+                    if (SSL3_BUFFER_get_left(&s->rlayer.rbuf) == 0) {
+                        /* no read-ahead left? */
+                        BIO *bio;
+                        /*
+                         * In the case where we try to read application data,
+                         * but we trigger an SSL handshake, we return -1 with
+                         * the retry option set.  Otherwise renegotiation may
+                         * cause nasty problems in the blocking world
+                         */
+                        s->rwstate = SSL_READING;
+                        bio = SSL_get_rbio(s);
+                        BIO_clear_retry_flags(bio);
+                        BIO_set_retry_read(bio);
+                        return (-1);
+                    }
+                }
+            }
+        }
+        /*
+         * we either finished a handshake or ignored the request, now try
+         * again to obtain the (application) data we were asked for
+         */
+        goto start;
+    }
+
+    if (s->rlayer.d->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH) {
+        int alert_level = s->rlayer.d->alert_fragment[0];
+        int alert_descr = s->rlayer.d->alert_fragment[1];
+
+        s->rlayer.d->alert_fragment_len = 0;
+
+        if (s->msg_callback)
+            s->msg_callback(0, s->version, SSL3_RT_ALERT,
+                            s->rlayer.d->alert_fragment, 2, s,
+                            s->msg_callback_arg);
+
+        if (s->info_callback != NULL)
+            cb = s->info_callback;
+        else if (s->ctx->info_callback != NULL)
+            cb = s->ctx->info_callback;
+
+        if (cb != NULL) {
+            j = (alert_level << 8) | alert_descr;
+            cb(s, SSL_CB_READ_ALERT, j);
+        }
+
+        if (alert_level == SSL3_AL_WARNING) {
+            s->s3->warn_alert = alert_descr;
+            if (alert_descr == SSL_AD_CLOSE_NOTIFY) {
+#ifndef OPENSSL_NO_SCTP
+                /*
+                 * With SCTP and streams the socket may deliver app data
+                 * after a close_notify alert. We have to check this first so
+                 * that nothing gets discarded.
+                 */
+                if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
+                    BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) {
+                    s->d1->shutdown_received = 1;
+                    s->rwstate = SSL_READING;
+                    BIO_clear_retry_flags(SSL_get_rbio(s));
+                    BIO_set_retry_read(SSL_get_rbio(s));
+                    return -1;
+                }
+#endif
+                s->shutdown |= SSL_RECEIVED_SHUTDOWN;
+                return (0);
+            }
+#if 0
+            /* XXX: this is a possible improvement in the future */
+            /* now check if it's a missing record */
+            if (alert_descr == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE) {
+                unsigned short seq;
+                unsigned int frag_off;
+                unsigned char *p = &(s->rlayer.d->alert_fragment[2]);
+
+                n2s(p, seq);
+                n2l3(p, frag_off);
+
+                dtls1_retransmit_message(s,
+                                         dtls1_get_queue_priority
+                                         (frag->msg_header.seq, 0), frag_off,
+                                         &found);
+                if (!found && SSL_in_init(s)) {
+                    /*
+                     * fprintf( stderr,"in init = %d\n", SSL_in_init(s));
+                     */
+                    /*
+                     * requested a message not yet sent, send an alert
+                     * ourselves
+                     */
+                    ssl3_send_alert(s, SSL3_AL_WARNING,
+                                    DTLS1_AD_MISSING_HANDSHAKE_MESSAGE);
+                }
+            }
+#endif
+        } else if (alert_level == SSL3_AL_FATAL) {
+            char tmp[16];
+
+            s->rwstate = SSL_NOTHING;
+            s->s3->fatal_alert = alert_descr;
+            SSLerr(SSL_F_DTLS1_READ_BYTES,
+                   SSL_AD_REASON_OFFSET + alert_descr);
+            BIO_snprintf(tmp, sizeof tmp, "%d", alert_descr);
+            ERR_add_error_data(2, "SSL alert number ", tmp);
+            s->shutdown |= SSL_RECEIVED_SHUTDOWN;
+            SSL_CTX_remove_session(s->ctx, s->session);
+            return (0);
+        } else {
+            al = SSL_AD_ILLEGAL_PARAMETER;
+            SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNKNOWN_ALERT_TYPE);
+            goto f_err;
+        }
+
+        goto start;
+    }
+
+    if (s->shutdown & SSL_SENT_SHUTDOWN) { /* but we have not received a
+                                            * shutdown */
+        s->rwstate = SSL_NOTHING;
+        rr->length = 0;
+        return (0);
+    }
+
+    if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) {
+        struct ccs_header_st ccs_hdr;
+        unsigned int ccs_hdr_len = DTLS1_CCS_HEADER_LENGTH;
+
+        dtls1_get_ccs_header(rr->data, &ccs_hdr);
+
+        if (s->version == DTLS1_BAD_VER)
+            ccs_hdr_len = 3;
+
+        /*
+         * 'Change Cipher Spec' is just a single byte, so we know exactly
+         * what the record payload has to look like
+         */
+        /* XDTLS: check that epoch is consistent */
+        if ((rr->length != ccs_hdr_len) ||
+            (rr->off != 0) || (rr->data[0] != SSL3_MT_CCS)) {
+            i = SSL_AD_ILLEGAL_PARAMETER;
+            SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_BAD_CHANGE_CIPHER_SPEC);
+            goto err;
+        }
+
+        rr->length = 0;
+
+        if (s->msg_callback)
+            s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC,
+                            rr->data, 1, s, s->msg_callback_arg);
+
+        /*
+         * We can't process a CCS now, because previous handshake messages
+         * are still missing, so just drop it.
+         */
+        if (!s->d1->change_cipher_spec_ok) {
+            goto start;
+        }
+
+        s->d1->change_cipher_spec_ok = 0;
+
+        s->s3->change_cipher_spec = 1;
+        if (!ssl3_do_change_cipher_spec(s))
+            goto err;
+
+        /* do this whenever CCS is processed */
+        dtls1_reset_seq_numbers(s, SSL3_CC_READ);
+
+        if (s->version == DTLS1_BAD_VER)
+            s->d1->handshake_read_seq++;
+
+#ifndef OPENSSL_NO_SCTP
+        /*
+         * Remember that a CCS has been received, so that an old key of
+         * SCTP-Auth can be deleted when a CCS is sent. Will be ignored if no
+         * SCTP is used
+         */
+        BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL);
+#endif
+
+        goto start;
+    }
+
+    /*
+     * Unexpected handshake message (Client Hello, or protocol violation)
+     */
+    if ((s->rlayer.d->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
+        !s->in_handshake) {
+        struct hm_header_st msg_hdr;
+
+        /* this may just be a stale retransmit */
+        dtls1_get_message_header(rr->data, &msg_hdr);
+        if (rr->epoch != s->rlayer.d->r_epoch) {
+            rr->length = 0;
+            goto start;
+        }
+
+        /*
+         * If we are server, we may have a repeated FINISHED of the client
+         * here, then retransmit our CCS and FINISHED.
+         */
+        if (msg_hdr.type == SSL3_MT_FINISHED) {
+            if (dtls1_check_timeout_num(s) < 0)
+                return -1;
+
+            dtls1_retransmit_buffered_messages(s);
+            rr->length = 0;
+            goto start;
+        }
+
+        if (((s->state & SSL_ST_MASK) == SSL_ST_OK) &&
+            !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) {
+            s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
+            s->renegotiate = 1;
+            s->new_session = 1;
+        }
+        i = s->handshake_func(s);
+        if (i < 0)
+            return (i);
+        if (i == 0) {
+            SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
+            return (-1);
+        }
+
+        if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
+            if (SSL3_BUFFER_get_left(&s->rlayer.rbuf) == 0) {
+                /* no read-ahead left? */
+                BIO *bio;
+                /*
+                 * In the case where we try to read application data, but we
+                 * trigger an SSL handshake, we return -1 with the retry
+                 * option set.  Otherwise renegotiation may cause nasty
+                 * problems in the blocking world
+                 */
+                s->rwstate = SSL_READING;
+                bio = SSL_get_rbio(s);
+                BIO_clear_retry_flags(bio);
+                BIO_set_retry_read(bio);
+                return (-1);
+            }
+        }
+        goto start;
+    }
+
+    switch (rr->type) {
+    default:
+        /* TLS just ignores unknown message types */
+        if (s->version == TLS1_VERSION) {
+            rr->length = 0;
+            goto start;
+        }
+        al = SSL_AD_UNEXPECTED_MESSAGE;
+        SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
+        goto f_err;
+    case SSL3_RT_CHANGE_CIPHER_SPEC:
+    case SSL3_RT_ALERT:
+    case SSL3_RT_HANDSHAKE:
+        /*
+         * we already handled all of these, with the possible exception of
+         * SSL3_RT_HANDSHAKE when s->in_handshake is set, but that should not
+         * happen when type != rr->type
+         */
+        al = SSL_AD_UNEXPECTED_MESSAGE;
+        SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
+        goto f_err;
+    case 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 &&
+            (s->s3->total_renegotiations != 0) &&
+            (((s->state & SSL_ST_CONNECT) &&
+              (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
+              (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
+             ) || ((s->state & SSL_ST_ACCEPT) &&
+                   (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
+                   (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
+             )
+            )) {
+            s->s3->in_read_app_data = 2;
+            return (-1);
+        } else {
+            al = SSL_AD_UNEXPECTED_MESSAGE;
+            SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
+            goto f_err;
+        }
+    }
+    /* not reached */
+
+ f_err:
+    ssl3_send_alert(s, SSL3_AL_FATAL, al);
+ err:
+    return (-1);
+}
+
+
+        /*
+         * this only happens when a client hello is received and a handshake
+         * is started.
+         */
+static int
+have_handshake_fragment(SSL *s, int type, unsigned char *buf,
+                        int len, int peek)
+{
+
+    if ((type == SSL3_RT_HANDSHAKE)
+            && (s->rlayer.d->handshake_fragment_len > 0))
+        /* (partially) satisfy request from storage */
+    {
+        unsigned char *src = s->rlayer.d->handshake_fragment;
+        unsigned char *dst = buf;
+        unsigned int k, n;
+
+        /* peek == 0 */
+        n = 0;
+        while ((len > 0) && (s->rlayer.d->handshake_fragment_len > 0)) {
+            *dst++ = *src++;
+            len--;
+            s->rlayer.d->handshake_fragment_len--;
+            n++;
+        }
+        /* move any remaining fragment bytes: */
+        for (k = 0; k < s->rlayer.d->handshake_fragment_len; k++)
+            s->rlayer.d->handshake_fragment[k] = *src++;
+        return n;
+    }
+
+    return 0;
+}
+
+/*
+ * 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->rwstate = SSL_NOTHING;
+    i = do_dtls1_write(s, type, buf, len, 0);
+    return i;
+}
+
+int do_dtls1_write(SSL *s, int type, const unsigned char *buf,
+                   unsigned int len, int create_empty_fragment)
+{
+    unsigned char *p, *pseq;
+    int i, mac_size, clear = 0;
+    int prefix_len = 0;
+    int eivlen;
+    SSL3_RECORD *wr;
+    SSL3_BUFFER *wb;
+    SSL_SESSION *sess;
+
+    wb = &s->rlayer.wbuf;
+
+    /*
+     * first check if there is a SSL3_BUFFER still being written out.  This
+     * will happen with non blocking IO
+     */
+    if (SSL3_BUFFER_get_left(wb) != 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, lets send it */
+    if (s->s3->alert_dispatch) {
+        i = s->method->ssl_dispatch_alert(s);
+        if (i <= 0)
+            return (i);
+        /* if it went, fall through and send more stuff */
+    }
+
+    if (len == 0 && !create_empty_fragment)
+        return 0;
+
+    wr = &s->rlayer.wrec;
+    sess = s->session;
+
+    if ((sess == NULL) ||
+        (s->enc_write_ctx == NULL) || (EVP_MD_CTX_md(s->write_hash) == NULL))
+        clear = 1;
+
+    if (clear)
+        mac_size = 0;
+    else {
+        mac_size = EVP_MD_CTX_size(s->write_hash);
+        if (mac_size < 0)
+            goto err;
+    }
+
+    p = wb->buf + prefix_len;
+
+    /* write the header */
+
+    *(p++) = type & 0xff;
+    wr->type = type;
+    /*
+     * 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;
+    }
+
+    /* field where we are to write out packet epoch, seq num and len */
+    pseq = p;
+    p += 10;
+
+    /* Explicit IV length, block ciphers appropriate version flag */
+    if (s->enc_write_ctx) {
+        int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
+        if (mode == EVP_CIPH_CBC_MODE) {
+            eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
+            if (eivlen <= 1)
+                eivlen = 0;
+        }
+        /* Need explicit part of IV for GCM mode */
+        else if (mode == EVP_CIPH_GCM_MODE)
+            eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
+        else
+            eivlen = 0;
+    } else
+        eivlen = 0;
+
+    /* lets setup the record stuff. */
+    wr->data = p + eivlen;      /* make room for IV in case of CBC */
+    wr->length = (int)len;
+    wr->input = (unsigned char *)buf;
+
+    /*
+     * we now 'read' from wr->input, wr->length bytes into wr->data
+     */
+
+    /* first we compress */
+    if (s->compress != NULL) {
+        if (!ssl3_do_compress(s)) {
+            SSLerr(SSL_F_DO_DTLS1_WRITE, SSL_R_COMPRESSION_FAILURE);
+            goto err;
+        }
+    } else {
+        memcpy(wr->data, wr->input, wr->length);
+        wr->input = wr->data;
+    }
+
+    /*
+     * we should still have the output to wr->data and the input from
+     * wr->input.  Length should be wr->length. wr->data still points in the
+     * wb->buf
+     */
+
+    if (mac_size != 0) {
+        if (s->method->ssl3_enc->mac(s, &(p[wr->length + eivlen]), 1) < 0)
+            goto err;
+        wr->length += mac_size;
+    }
+
+    /* this is true regardless of mac size */
+    wr->input = p;
+    wr->data = p;
+
+    if (eivlen)
+        wr->length += eivlen;
+
+    if (s->method->ssl3_enc->enc(s, 1) < 1)
+        goto err;
+
+    /* record length after mac and block padding */
+    /*
+     * if (type == SSL3_RT_APPLICATION_DATA || (type == SSL3_RT_ALERT && !
+     * SSL_in_init(s)))
+     */
+
+    /* there's only one epoch between handshake and app data */
+
+    s2n(s->rlayer.d->w_epoch, pseq);
+
+    /* XDTLS: ?? */
+    /*
+     * else s2n(s->d1->handshake_epoch, pseq);
+     */
+
+    memcpy(pseq, &(s->rlayer.write_sequence[2]), 6);
+    pseq += 6;
+    s2n(wr->length, pseq);
+
+    if (s->msg_callback)
+        s->msg_callback(1, 0, SSL3_RT_HEADER, pseq - DTLS1_RT_HEADER_LENGTH,
+                        DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
+
+    /*
+     * we should now have wr->data pointing to the encrypted data, which is
+     * wr->length long
+     */
+    wr->type = type;            /* not needed but helps for debugging */
+    wr->length += DTLS1_RT_HEADER_LENGTH;
+
+    ssl3_record_sequence_update(&(s->rlayer.write_sequence[0]));
+
+    if (create_empty_fragment) {
+        /*
+         * we are in a recursive call; just return the length, don't write
+         * out anything here
+         */
+        return wr->length;
+    }
+
+    /* now let's set up wb */
+    wb->left = prefix_len + wr->length;
+    wb->offset = 0;
+
+    /*
+     * memorize arguments so that ssl3_write_pending can detect bad write
+     * retries later
+     */
+    s->rlayer.wpend_tot = len;
+    s->rlayer.wpend_buf = buf;
+    s->rlayer.wpend_type = type;
+    s->rlayer.wpend_ret = len;
+
+    /* we now just need to write the buffer */
+    return ssl3_write_pending(s, type, buf, len);
+ err:
+    return -1;
+}
+
+DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr,
+                                      unsigned int *is_next_epoch)
+{
+
+    *is_next_epoch = 0;
+
+    /* In current epoch, accept HM, CCS, DATA, & ALERT */
+    if (rr->epoch == s->rlayer.d->r_epoch)
+        return &s->rlayer.d->bitmap;
+
+    /* Only HM and ALERT messages can be from the next epoch */
+    else if (rr->epoch == (unsigned long)(s->rlayer.d->r_epoch + 1) &&
+            (rr->type == SSL3_RT_HANDSHAKE || rr->type == SSL3_RT_ALERT)) {
+        *is_next_epoch = 1;
+        return &s->rlayer.d->next_bitmap;
+    }
+
+    return NULL;
+}
+
+void dtls1_reset_seq_numbers(SSL *s, int rw)
+{
+    unsigned char *seq;
+    unsigned int seq_bytes = sizeof(s->rlayer.read_sequence);
+
+    if (rw & SSL3_CC_READ) {
+        seq = s->rlayer.read_sequence;
+        s->rlayer.d->r_epoch++;
+        memcpy(&(s->rlayer.d->bitmap), &(s->rlayer.d->next_bitmap),
+            sizeof(DTLS1_BITMAP));
+        memset(&(s->rlayer.d->next_bitmap), 0x00, sizeof(DTLS1_BITMAP));
+    } else {
+        seq = s->rlayer.write_sequence;
+        memcpy(s->rlayer.d->last_write_sequence, seq,
+               sizeof(s->rlayer.write_sequence));
+        s->rlayer.d->w_epoch++;
+    }
+
+    memset(seq, 0x00, seq_bytes);
+}