xref: /freebsd-10.3-release/crypto/openssl/ssl/d1_clnt.c

/* ssl/d1_clnt.c */
/*
 * DTLS implementation written by Nagendra Modadugu
 * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
 */
/* ====================================================================
 * Copyright (c) 1999-2007 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 "ssl_locl.h"
#ifndef OPENSSL_NO_KRB5
# include "kssl_lcl.h"
#endif
#include <openssl/buffer.h>
#include <openssl/rand.h>
#include <openssl/objects.h>
#include <openssl/evp.h>
#include <openssl/md5.h>
#include <openssl/bn.h>
#ifndef OPENSSL_NO_DH
# include <openssl/dh.h>
#endif

static const SSL_METHOD *dtls1_get_client_method(int ver);
static int dtls1_get_hello_verify(SSL *s);

static const SSL_METHOD *dtls1_get_client_method(int ver)
{
    if (ver == DTLS1_VERSION || ver == DTLS1_BAD_VER)
        return (DTLSv1_client_method());
    else
        return (NULL);
}

IMPLEMENT_dtls1_meth_func(DTLSv1_client_method,
                          ssl_undefined_function,
                          dtls1_connect, dtls1_get_client_method)

int dtls1_connect(SSL *s)
{
    BUF_MEM *buf = NULL;
    unsigned long Time = (unsigned long)time(NULL);
    void (*cb) (const SSL *ssl, int type, int val) = NULL;
    int ret = -1;
    int new_state, state, skip = 0;
#ifndef OPENSSL_NO_SCTP
    unsigned char sctpauthkey[64];
    char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
#endif

    RAND_add(&Time, sizeof(Time), 0);
    ERR_clear_error();
    clear_sys_error();

    if (s->info_callback != NULL)
        cb = s->info_callback;
    else if (s->ctx->info_callback != NULL)
        cb = s->ctx->info_callback;

    s->in_handshake++;
    if (!SSL_in_init(s) || SSL_in_before(s))
        SSL_clear(s);

#ifndef OPENSSL_NO_SCTP
    /*
     * Notify SCTP BIO socket to enter handshake mode and prevent stream
     * identifier other than 0. Will be ignored if no SCTP is used.
     */
    BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE,
             s->in_handshake, NULL);
#endif

#ifndef OPENSSL_NO_HEARTBEATS
    /*
     * If we're awaiting a HeartbeatResponse, pretend we already got and
     * don't await it anymore, because Heartbeats don't make sense during
     * handshakes anyway.
     */
    if (s->tlsext_hb_pending) {
        dtls1_stop_timer(s);
        s->tlsext_hb_pending = 0;
        s->tlsext_hb_seq++;
    }
#endif

    for (;;) {
        state = s->state;

        switch (s->state) {
        case SSL_ST_RENEGOTIATE:
            s->renegotiate = 1;
            s->state = SSL_ST_CONNECT;
            s->ctx->stats.sess_connect_renegotiate++;
            /* break */
        case SSL_ST_BEFORE:
        case SSL_ST_CONNECT:
        case SSL_ST_BEFORE | SSL_ST_CONNECT:
        case SSL_ST_OK | SSL_ST_CONNECT:

            s->server = 0;
            if (cb != NULL)
                cb(s, SSL_CB_HANDSHAKE_START, 1);

            if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00) &&
                (s->version & 0xff00) != (DTLS1_BAD_VER & 0xff00)) {
                SSLerr(SSL_F_DTLS1_CONNECT, ERR_R_INTERNAL_ERROR);
                ret = -1;
                s->state = SSL_ST_ERR;
                goto end;
            }

            /* s->version=SSL3_VERSION; */
            s->type = SSL_ST_CONNECT;

            if (s->init_buf == NULL) {
                if ((buf = BUF_MEM_new()) == NULL) {
                    ret = -1;
                    s->state = SSL_ST_ERR;
                    goto end;
                }
                if (!BUF_MEM_grow(buf, SSL3_RT_MAX_PLAIN_LENGTH)) {
                    ret = -1;
                    s->state = SSL_ST_ERR;
                    goto end;
                }
                s->init_buf = buf;
                buf = NULL;
            }

            if (!ssl3_setup_buffers(s)) {
                ret = -1;
                s->state = SSL_ST_ERR;
                goto end;
            }

            /* setup buffing BIO */
            if (!ssl_init_wbio_buffer(s, 0)) {
                ret = -1;
                s->state = SSL_ST_ERR;
                goto end;
            }

            /* don't push the buffering BIO quite yet */

            s->state = SSL3_ST_CW_CLNT_HELLO_A;
            s->ctx->stats.sess_connect++;
            s->init_num = 0;
            /* mark client_random uninitialized */
            memset(s->s3->client_random, 0, sizeof(s->s3->client_random));
            s->d1->send_cookie = 0;
            s->hit = 0;
            s->d1->change_cipher_spec_ok = 0;
            /*
             * Should have been reset by ssl3_get_finished, too.
             */
            s->s3->change_cipher_spec = 0;
            break;

#ifndef OPENSSL_NO_SCTP
        case DTLS1_SCTP_ST_CR_READ_SOCK:

            if (BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) {
                s->s3->in_read_app_data = 2;
                s->rwstate = SSL_READING;
                BIO_clear_retry_flags(SSL_get_rbio(s));
                BIO_set_retry_read(SSL_get_rbio(s));
                ret = -1;
                goto end;
            }

            s->state = s->s3->tmp.next_state;
            break;

        case DTLS1_SCTP_ST_CW_WRITE_SOCK:
            /* read app data until dry event */

            ret = BIO_dgram_sctp_wait_for_dry(SSL_get_wbio(s));
            if (ret < 0)
                goto end;

            if (ret == 0) {
                s->s3->in_read_app_data = 2;
                s->rwstate = SSL_READING;
                BIO_clear_retry_flags(SSL_get_rbio(s));
                BIO_set_retry_read(SSL_get_rbio(s));
                ret = -1;
                goto end;
            }

            s->state = s->d1->next_state;
            break;
#endif

        case SSL3_ST_CW_CLNT_HELLO_A:
            s->shutdown = 0;

            /* every DTLS ClientHello resets Finished MAC */
            ssl3_init_finished_mac(s);

        case SSL3_ST_CW_CLNT_HELLO_B:
            dtls1_start_timer(s);
            ret = dtls1_client_hello(s);
            if (ret <= 0)
                goto end;

            if (s->d1->send_cookie) {
                s->state = SSL3_ST_CW_FLUSH;
                s->s3->tmp.next_state = SSL3_ST_CR_SRVR_HELLO_A;
            } else
                s->state = SSL3_ST_CR_SRVR_HELLO_A;

            s->init_num = 0;

#ifndef OPENSSL_NO_SCTP
            /* Disable buffering for SCTP */
            if (!BIO_dgram_is_sctp(SSL_get_wbio(s))) {
#endif
                /*
                 * turn on buffering for the next lot of output
                 */
                if (s->bbio != s->wbio)
                    s->wbio = BIO_push(s->bbio, s->wbio);
#ifndef OPENSSL_NO_SCTP
            }
#endif

            break;

        case SSL3_ST_CR_SRVR_HELLO_A:
        case SSL3_ST_CR_SRVR_HELLO_B:
            ret = ssl3_get_server_hello(s);
            if (ret <= 0)
                goto end;
            else {
                if (s->hit) {
#ifndef OPENSSL_NO_SCTP
                    /*
                     * Add new shared key for SCTP-Auth, will be ignored if
                     * no SCTP used.
                     */
                    snprintf((char *)labelbuffer,
                             sizeof(DTLS1_SCTP_AUTH_LABEL),
                             DTLS1_SCTP_AUTH_LABEL);

                    if (SSL_export_keying_material(s, sctpauthkey,
                                               sizeof(sctpauthkey),
                                               labelbuffer,
                                               sizeof(labelbuffer), NULL, 0,
                                               0) <= 0) {
                        ret = -1;
                        s->state = SSL_ST_ERR;
                        goto end;
                    }

                    BIO_ctrl(SSL_get_wbio(s),
                             BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
                             sizeof(sctpauthkey), sctpauthkey);
#endif

                    s->state = SSL3_ST_CR_FINISHED_A;
                    if (s->tlsext_ticket_expected) {
                        /* receive renewed session ticket */
                        s->state = SSL3_ST_CR_SESSION_TICKET_A;
                    }
                } else
                    s->state = DTLS1_ST_CR_HELLO_VERIFY_REQUEST_A;
            }
            s->init_num = 0;
            break;

        case DTLS1_ST_CR_HELLO_VERIFY_REQUEST_A:
        case DTLS1_ST_CR_HELLO_VERIFY_REQUEST_B:

            ret = dtls1_get_hello_verify(s);
            if (ret <= 0)
                goto end;
            dtls1_stop_timer(s);
            if (s->d1->send_cookie) /* start again, with a cookie */
                s->state = SSL3_ST_CW_CLNT_HELLO_A;
            else
                s->state = SSL3_ST_CR_CERT_A;
            s->init_num = 0;
            break;

        case SSL3_ST_CR_CERT_A:
        case SSL3_ST_CR_CERT_B:
            /* Check if it is anon DH or PSK */
            if (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL) &&
                !(s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK)) {
                ret = ssl3_get_server_certificate(s);
                if (ret <= 0)
                    goto end;
#ifndef OPENSSL_NO_TLSEXT
                if (s->tlsext_status_expected)
                    s->state = SSL3_ST_CR_CERT_STATUS_A;
                else
                    s->state = SSL3_ST_CR_KEY_EXCH_A;
            } else {
                skip = 1;
                s->state = SSL3_ST_CR_KEY_EXCH_A;
            }
#else
            } else
                skip = 1;

            s->state = SSL3_ST_CR_KEY_EXCH_A;
#endif
            s->init_num = 0;
            break;

        case SSL3_ST_CR_KEY_EXCH_A:
        case SSL3_ST_CR_KEY_EXCH_B:
            ret = ssl3_get_key_exchange(s);
            if (ret <= 0)
                goto end;
            s->state = SSL3_ST_CR_CERT_REQ_A;
            s->init_num = 0;

            /*
             * at this point we check that we have the required stuff from
             * the server
             */
            if (!ssl3_check_cert_and_algorithm(s)) {
                ret = -1;
                s->state = SSL_ST_ERR;
                goto end;
            }
            break;

        case SSL3_ST_CR_CERT_REQ_A:
        case SSL3_ST_CR_CERT_REQ_B:
            ret = ssl3_get_certificate_request(s);
            if (ret <= 0)
                goto end;
            s->state = SSL3_ST_CR_SRVR_DONE_A;
            s->init_num = 0;
            break;

        case SSL3_ST_CR_SRVR_DONE_A:
        case SSL3_ST_CR_SRVR_DONE_B:
            ret = ssl3_get_server_done(s);
            if (ret <= 0)
                goto end;
            dtls1_stop_timer(s);
            if (s->s3->tmp.cert_req)
                s->s3->tmp.next_state = SSL3_ST_CW_CERT_A;
            else
                s->s3->tmp.next_state = SSL3_ST_CW_KEY_EXCH_A;
            s->init_num = 0;

#ifndef OPENSSL_NO_SCTP
            if (BIO_dgram_is_sctp(SSL_get_wbio(s)) &&
                state == SSL_ST_RENEGOTIATE)
                s->state = DTLS1_SCTP_ST_CR_READ_SOCK;
            else
#endif
                s->state = s->s3->tmp.next_state;
            break;

        case SSL3_ST_CW_CERT_A:
        case SSL3_ST_CW_CERT_B:
        case SSL3_ST_CW_CERT_C:
        case SSL3_ST_CW_CERT_D:
            dtls1_start_timer(s);
            ret = dtls1_send_client_certificate(s);
            if (ret <= 0)
                goto end;
            s->state = SSL3_ST_CW_KEY_EXCH_A;
            s->init_num = 0;
            break;

        case SSL3_ST_CW_KEY_EXCH_A:
        case SSL3_ST_CW_KEY_EXCH_B:
            dtls1_start_timer(s);
            ret = dtls1_send_client_key_exchange(s);
            if (ret <= 0)
                goto end;

#ifndef OPENSSL_NO_SCTP
            /*
             * Add new shared key for SCTP-Auth, will be ignored if no SCTP
             * used.
             */
            snprintf((char *)labelbuffer, sizeof(DTLS1_SCTP_AUTH_LABEL),
                     DTLS1_SCTP_AUTH_LABEL);

            if (SSL_export_keying_material(s, sctpauthkey,
                                       sizeof(sctpauthkey), labelbuffer,
                                       sizeof(labelbuffer), NULL, 0, 0) <= 0) {
                ret = -1;
                s->state = SSL_ST_ERR;
                goto end;
            }

            BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
                     sizeof(sctpauthkey), sctpauthkey);
#endif

            /*
             * EAY EAY EAY need to check for DH fix cert sent back
             */
            /*
             * For TLS, cert_req is set to 2, so a cert chain of nothing is
             * sent, but no verify packet is sent
             */
            if (s->s3->tmp.cert_req == 1) {
                s->state = SSL3_ST_CW_CERT_VRFY_A;
            } else {
#ifndef OPENSSL_NO_SCTP
                if (BIO_dgram_is_sctp(SSL_get_wbio(s))) {
                    s->d1->next_state = SSL3_ST_CW_CHANGE_A;
                    s->state = DTLS1_SCTP_ST_CW_WRITE_SOCK;
                } else
#endif
                    s->state = SSL3_ST_CW_CHANGE_A;
            }

            s->init_num = 0;
            break;

        case SSL3_ST_CW_CERT_VRFY_A:
        case SSL3_ST_CW_CERT_VRFY_B:
            dtls1_start_timer(s);
            ret = dtls1_send_client_verify(s);
            if (ret <= 0)
                goto end;
#ifndef OPENSSL_NO_SCTP
            if (BIO_dgram_is_sctp(SSL_get_wbio(s))) {
                s->d1->next_state = SSL3_ST_CW_CHANGE_A;
                s->state = DTLS1_SCTP_ST_CW_WRITE_SOCK;
            } else
#endif
                s->state = SSL3_ST_CW_CHANGE_A;
            s->init_num = 0;
            break;

        case SSL3_ST_CW_CHANGE_A:
        case SSL3_ST_CW_CHANGE_B:
            if (!s->hit)
                dtls1_start_timer(s);
            ret = dtls1_send_change_cipher_spec(s,
                                                SSL3_ST_CW_CHANGE_A,
                                                SSL3_ST_CW_CHANGE_B);
            if (ret <= 0)
                goto end;

            s->state = SSL3_ST_CW_FINISHED_A;
            s->init_num = 0;

            s->session->cipher = s->s3->tmp.new_cipher;
#ifdef OPENSSL_NO_COMP
            s->session->compress_meth = 0;
#else
            if (s->s3->tmp.new_compression == NULL)
                s->session->compress_meth = 0;
            else
                s->session->compress_meth = s->s3->tmp.new_compression->id;
#endif
            if (!s->method->ssl3_enc->setup_key_block(s)) {
                ret = -1;
                s->state = SSL_ST_ERR;
                goto end;
            }

            if (!s->method->ssl3_enc->change_cipher_state(s,
                                                          SSL3_CHANGE_CIPHER_CLIENT_WRITE))
            {
                ret = -1;
                s->state = SSL_ST_ERR;
                goto end;
            }
#ifndef OPENSSL_NO_SCTP
            if (s->hit) {
                /*
                 * Change to new shared key of SCTP-Auth, will be ignored if
                 * no SCTP used.
                 */
                BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
                         0, NULL);
            }
#endif

            dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
            break;

        case SSL3_ST_CW_FINISHED_A:
        case SSL3_ST_CW_FINISHED_B:
            if (!s->hit)
                dtls1_start_timer(s);
            ret = dtls1_send_finished(s,
                                      SSL3_ST_CW_FINISHED_A,
                                      SSL3_ST_CW_FINISHED_B,
                                      s->method->
                                      ssl3_enc->client_finished_label,
                                      s->method->
                                      ssl3_enc->client_finished_label_len);
            if (ret <= 0)
                goto end;
            s->state = SSL3_ST_CW_FLUSH;

            /* clear flags */
            s->s3->flags &= ~SSL3_FLAGS_POP_BUFFER;
            if (s->hit) {
                s->s3->tmp.next_state = SSL_ST_OK;
#ifndef OPENSSL_NO_SCTP
                if (BIO_dgram_is_sctp(SSL_get_wbio(s))) {
                    s->d1->next_state = s->s3->tmp.next_state;
                    s->s3->tmp.next_state = DTLS1_SCTP_ST_CW_WRITE_SOCK;
                }
#endif
                if (s->s3->flags & SSL3_FLAGS_DELAY_CLIENT_FINISHED) {
                    s->state = SSL_ST_OK;
#ifndef OPENSSL_NO_SCTP
                    if (BIO_dgram_is_sctp(SSL_get_wbio(s))) {
                        s->d1->next_state = SSL_ST_OK;
                        s->state = DTLS1_SCTP_ST_CW_WRITE_SOCK;
                    }
#endif
                    s->s3->flags |= SSL3_FLAGS_POP_BUFFER;
                    s->s3->delay_buf_pop_ret = 0;
                }
            } else {
#ifndef OPENSSL_NO_SCTP
                /*
                 * Change to new shared key of SCTP-Auth, will be ignored if
                 * no SCTP used.
                 */
                BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
                         0, NULL);
#endif

#ifndef OPENSSL_NO_TLSEXT
                /*
                 * Allow NewSessionTicket if ticket expected
                 */
                if (s->tlsext_ticket_expected)
                    s->s3->tmp.next_state = SSL3_ST_CR_SESSION_TICKET_A;
                else
#endif

                    s->s3->tmp.next_state = SSL3_ST_CR_FINISHED_A;
            }
            s->init_num = 0;
            break;

#ifndef OPENSSL_NO_TLSEXT
        case SSL3_ST_CR_SESSION_TICKET_A:
        case SSL3_ST_CR_SESSION_TICKET_B:
            ret = ssl3_get_new_session_ticket(s);
            if (ret <= 0)
                goto end;
            s->state = SSL3_ST_CR_FINISHED_A;
            s->init_num = 0;
            break;

        case SSL3_ST_CR_CERT_STATUS_A:
        case SSL3_ST_CR_CERT_STATUS_B:
            ret = ssl3_get_cert_status(s);
            if (ret <= 0)
                goto end;
            s->state = SSL3_ST_CR_KEY_EXCH_A;
            s->init_num = 0;
            break;
#endif

        case SSL3_ST_CR_FINISHED_A:
        case SSL3_ST_CR_FINISHED_B:
            s->d1->change_cipher_spec_ok = 1;
            ret = ssl3_get_finished(s, SSL3_ST_CR_FINISHED_A,
                                    SSL3_ST_CR_FINISHED_B);
            if (ret <= 0)
                goto end;
            dtls1_stop_timer(s);

            if (s->hit)
                s->state = SSL3_ST_CW_CHANGE_A;
            else
                s->state = SSL_ST_OK;

#ifndef OPENSSL_NO_SCTP
            if (BIO_dgram_is_sctp(SSL_get_wbio(s)) &&
                state == SSL_ST_RENEGOTIATE) {
                s->d1->next_state = s->state;
                s->state = DTLS1_SCTP_ST_CW_WRITE_SOCK;
            }
#endif

            s->init_num = 0;
            break;

        case SSL3_ST_CW_FLUSH:
            s->rwstate = SSL_WRITING;
            if (BIO_flush(s->wbio) <= 0) {
                /*
                 * If the write error was fatal, stop trying
                 */
                if (!BIO_should_retry(s->wbio)) {
                    s->rwstate = SSL_NOTHING;
                    s->state = s->s3->tmp.next_state;
                }

                ret = -1;
                goto end;
            }
            s->rwstate = SSL_NOTHING;
            s->state = s->s3->tmp.next_state;
            break;

        case SSL_ST_OK:
            /* clean a few things up */
            ssl3_cleanup_key_block(s);

#if 0
            if (s->init_buf != NULL) {
                BUF_MEM_free(s->init_buf);
                s->init_buf = NULL;
            }
#endif

            /*
             * If we are not 'joining' the last two packets, remove the
             * buffering now
             */
            if (!(s->s3->flags & SSL3_FLAGS_POP_BUFFER))
                ssl_free_wbio_buffer(s);
            /* else do it later in ssl3_write */

            s->init_num = 0;
            s->renegotiate = 0;
            s->new_session = 0;

            ssl_update_cache(s, SSL_SESS_CACHE_CLIENT);
            if (s->hit)
                s->ctx->stats.sess_hit++;

            ret = 1;
            /* s->server=0; */
            s->handshake_func = dtls1_connect;
            s->ctx->stats.sess_connect_good++;

            if (cb != NULL)
                cb(s, SSL_CB_HANDSHAKE_DONE, 1);

            /* done with handshaking */
            s->d1->handshake_read_seq = 0;
            s->d1->next_handshake_write_seq = 0;
            dtls1_clear_received_buffer(s);
            goto end;
            /* break; */

        case SSL_ST_ERR:
        default:
            SSLerr(SSL_F_DTLS1_CONNECT, SSL_R_UNKNOWN_STATE);
            ret = -1;
            goto end;
            /* break; */
        }

        /* did we do anything */
        if (!s->s3->tmp.reuse_message && !skip) {
            if (s->debug) {
                if ((ret = BIO_flush(s->wbio)) <= 0)
                    goto end;
            }

            if ((cb != NULL) && (s->state != state)) {
                new_state = s->state;
                s->state = state;
                cb(s, SSL_CB_CONNECT_LOOP, 1);
                s->state = new_state;
            }
        }
        skip = 0;
    }
 end:
    s->in_handshake--;

#ifndef OPENSSL_NO_SCTP
    /*
     * Notify SCTP BIO socket to leave handshake mode and allow stream
     * identifier other than 0. Will be ignored if no SCTP is used.
     */
    BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE,
             s->in_handshake, NULL);
#endif

    if (buf != NULL)
        BUF_MEM_free(buf);
    if (cb != NULL)
        cb(s, SSL_CB_CONNECT_EXIT, ret);
    return (ret);
}

int dtls1_client_hello(SSL *s)
{
    unsigned char *buf;
    unsigned char *p, *d;
    unsigned int i, j;
    unsigned long l;
    SSL_COMP *comp;

    buf = (unsigned char *)s->init_buf->data;
    if (s->state == SSL3_ST_CW_CLNT_HELLO_A) {
        SSL_SESSION *sess = s->session;
        if ((s->session == NULL) || (s->session->ssl_version != s->version) ||
#ifdef OPENSSL_NO_TLSEXT
            !sess->session_id_length ||
#else
            (!sess->session_id_length && !sess->tlsext_tick) ||
#endif
            (s->session->not_resumable)) {
            if (!ssl_get_new_session(s, 0))
                goto err;
        }
        /* else use the pre-loaded session */

        p = s->s3->client_random;

        /*
         * if client_random is initialized, reuse it, we are required to use
         * same upon reply to HelloVerify
         */
        for (i = 0; p[i] == '\0' && i < sizeof(s->s3->client_random); i++) ;
        if (i == sizeof(s->s3->client_random))
            ssl_fill_hello_random(s, 0, p, sizeof(s->s3->client_random));

        /* Do the message type and length last */
        d = p = &(buf[DTLS1_HM_HEADER_LENGTH]);

        *(p++) = s->version >> 8;
        *(p++) = s->version & 0xff;
        s->client_version = s->version;

        /* Random stuff */
        memcpy(p, s->s3->client_random, SSL3_RANDOM_SIZE);
        p += SSL3_RANDOM_SIZE;

        /* Session ID */
        if (s->new_session)
            i = 0;
        else
            i = s->session->session_id_length;
        *(p++) = i;
        if (i != 0) {
            if (i > sizeof s->session->session_id) {
                SSLerr(SSL_F_DTLS1_CLIENT_HELLO, ERR_R_INTERNAL_ERROR);
                goto err;
            }
            memcpy(p, s->session->session_id, i);
            p += i;
        }

        /* cookie stuff */
        if (s->d1->cookie_len > sizeof(s->d1->cookie)) {
            SSLerr(SSL_F_DTLS1_CLIENT_HELLO, ERR_R_INTERNAL_ERROR);
            goto err;
        }
        *(p++) = s->d1->cookie_len;
        memcpy(p, s->d1->cookie, s->d1->cookie_len);
        p += s->d1->cookie_len;

        /* Ciphers supported */
        i = ssl_cipher_list_to_bytes(s, SSL_get_ciphers(s), &(p[2]), 0);
        if (i == 0) {
            SSLerr(SSL_F_DTLS1_CLIENT_HELLO, SSL_R_NO_CIPHERS_AVAILABLE);
            goto err;
        }
        s2n(i, p);
        p += i;

        /* COMPRESSION */
        if (s->ctx->comp_methods == NULL)
            j = 0;
        else
            j = sk_SSL_COMP_num(s->ctx->comp_methods);
        *(p++) = 1 + j;
        for (i = 0; i < j; i++) {
            comp = sk_SSL_COMP_value(s->ctx->comp_methods, i);
            *(p++) = comp->id;
        }
        *(p++) = 0;             /* Add the NULL method */

#ifndef OPENSSL_NO_TLSEXT
        /* TLS extensions */
        if (ssl_prepare_clienthello_tlsext(s) <= 0) {
            SSLerr(SSL_F_DTLS1_CLIENT_HELLO, SSL_R_CLIENTHELLO_TLSEXT);
            goto err;
        }
        if ((p =
             ssl_add_clienthello_tlsext(s, p,
                                        buf + SSL3_RT_MAX_PLAIN_LENGTH)) ==
            NULL) {
            SSLerr(SSL_F_DTLS1_CLIENT_HELLO, ERR_R_INTERNAL_ERROR);
            goto err;
        }
#endif

        l = (p - d);
        d = buf;

        d = dtls1_set_message_header(s, d, SSL3_MT_CLIENT_HELLO, l, 0, l);

        s->state = SSL3_ST_CW_CLNT_HELLO_B;
        /* number of bytes to write */
        s->init_num = p - buf;
        s->init_off = 0;

        /* buffer the message to handle re-xmits */
        dtls1_buffer_message(s, 0);
    }

    /* SSL3_ST_CW_CLNT_HELLO_B */
    return (dtls1_do_write(s, SSL3_RT_HANDSHAKE));
 err:
    return (-1);
}

static int dtls1_get_hello_verify(SSL *s)
{
    int n, al, ok = 0;
    unsigned char *data;
    unsigned int cookie_len;

    n = s->method->ssl_get_message(s,
                                   DTLS1_ST_CR_HELLO_VERIFY_REQUEST_A,
                                   DTLS1_ST_CR_HELLO_VERIFY_REQUEST_B,
                                   -1, s->max_cert_list, &ok);

    if (!ok)
        return ((int)n);

    if (s->s3->tmp.message_type != DTLS1_MT_HELLO_VERIFY_REQUEST) {
        s->d1->send_cookie = 0;
        s->s3->tmp.reuse_message = 1;
        return (1);
    }

    data = (unsigned char *)s->init_msg;

    if ((data[0] != (s->version >> 8)) || (data[1] != (s->version & 0xff))) {
        SSLerr(SSL_F_DTLS1_GET_HELLO_VERIFY, SSL_R_WRONG_SSL_VERSION);
        s->version = (s->version & 0xff00) | data[1];
        al = SSL_AD_PROTOCOL_VERSION;
        goto f_err;
    }
    data += 2;

    cookie_len = *(data++);
    if (cookie_len > sizeof(s->d1->cookie)) {
        al = SSL_AD_ILLEGAL_PARAMETER;
        goto f_err;
    }

    memcpy(s->d1->cookie, data, cookie_len);
    s->d1->cookie_len = cookie_len;

    s->d1->send_cookie = 1;
    return 1;

 f_err:
    ssl3_send_alert(s, SSL3_AL_FATAL, al);
    s->state = SSL_ST_ERR;
    return -1;
}

int dtls1_send_client_key_exchange(SSL *s)
{
    unsigned char *p, *d;
    int n;
    unsigned long alg_k;
#ifndef OPENSSL_NO_RSA
    unsigned char *q;
    EVP_PKEY *pkey = NULL;
#endif
#ifndef OPENSSL_NO_KRB5
    KSSL_ERR kssl_err;
#endif                          /* OPENSSL_NO_KRB5 */
#ifndef OPENSSL_NO_ECDH
    EC_KEY *clnt_ecdh = NULL;
    const EC_POINT *srvr_ecpoint = NULL;
    EVP_PKEY *srvr_pub_pkey = NULL;
    unsigned char *encodedPoint = NULL;
    int encoded_pt_len = 0;
    BN_CTX *bn_ctx = NULL;
#endif

    if (s->state == SSL3_ST_CW_KEY_EXCH_A) {
        d = (unsigned char *)s->init_buf->data;
        p = &(d[DTLS1_HM_HEADER_LENGTH]);

        alg_k = s->s3->tmp.new_cipher->algorithm_mkey;

        /* Fool emacs indentation */
        if (0) {
        }
#ifndef OPENSSL_NO_RSA
        else if (alg_k & SSL_kRSA) {
            RSA *rsa;
            unsigned char tmp_buf[SSL_MAX_MASTER_KEY_LENGTH];

            if (s->session->sess_cert == NULL) {
                /*
                 * We should always have a server certificate with SSL_kRSA.
                 */
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE,
                       ERR_R_INTERNAL_ERROR);
                goto err;
            }

            if (s->session->sess_cert->peer_rsa_tmp != NULL)
                rsa = s->session->sess_cert->peer_rsa_tmp;
            else {
                pkey =
                    X509_get_pubkey(s->session->
                                    sess_cert->peer_pkeys[SSL_PKEY_RSA_ENC].
                                    x509);
                if ((pkey == NULL) || (pkey->type != EVP_PKEY_RSA)
                    || (pkey->pkey.rsa == NULL)) {
                    SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE,
                           ERR_R_INTERNAL_ERROR);
                    goto err;
                }
                rsa = pkey->pkey.rsa;
                EVP_PKEY_free(pkey);
            }

            tmp_buf[0] = s->client_version >> 8;
            tmp_buf[1] = s->client_version & 0xff;
            if (RAND_bytes(&(tmp_buf[2]), sizeof tmp_buf - 2) <= 0)
                goto err;

            s->session->master_key_length = sizeof tmp_buf;

            q = p;
            /* Fix buf for TLS and [incidentally] DTLS */
            if (s->version > SSL3_VERSION)
                p += 2;
            n = RSA_public_encrypt(sizeof tmp_buf,
                                   tmp_buf, p, rsa, RSA_PKCS1_PADDING);
# ifdef PKCS1_CHECK
            if (s->options & SSL_OP_PKCS1_CHECK_1)
                p[1]++;
            if (s->options & SSL_OP_PKCS1_CHECK_2)
                tmp_buf[0] = 0x70;
# endif
            if (n <= 0) {
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE,
                       SSL_R_BAD_RSA_ENCRYPT);
                goto err;
            }

            /* Fix buf for TLS and [incidentally] DTLS */
            if (s->version > SSL3_VERSION) {
                s2n(n, q);
                n += 2;
            }

            s->session->master_key_length =
                s->method->ssl3_enc->generate_master_secret(s,
                                                            s->
                                                            session->master_key,
                                                            tmp_buf,
                                                            sizeof tmp_buf);
            OPENSSL_cleanse(tmp_buf, sizeof tmp_buf);
        }
#endif
#ifndef OPENSSL_NO_KRB5
        else if (alg_k & SSL_kKRB5) {
            krb5_error_code krb5rc;
            KSSL_CTX *kssl_ctx = s->kssl_ctx;
            /*  krb5_data   krb5_ap_req;  */
            krb5_data *enc_ticket;
            krb5_data authenticator, *authp = NULL;
            EVP_CIPHER_CTX ciph_ctx;
            const EVP_CIPHER *enc = NULL;
            unsigned char iv[EVP_MAX_IV_LENGTH];
            unsigned char tmp_buf[SSL_MAX_MASTER_KEY_LENGTH];
            unsigned char epms[SSL_MAX_MASTER_KEY_LENGTH + EVP_MAX_IV_LENGTH];
            int padl, outl = sizeof(epms);

            EVP_CIPHER_CTX_init(&ciph_ctx);

# ifdef KSSL_DEBUG
            printf("ssl3_send_client_key_exchange(%lx & %lx)\n",
                   alg_k, SSL_kKRB5);
# endif                         /* KSSL_DEBUG */

            authp = NULL;
# ifdef KRB5SENDAUTH
            if (KRB5SENDAUTH)
                authp = &authenticator;
# endif                         /* KRB5SENDAUTH */

            krb5rc = kssl_cget_tkt(kssl_ctx, &enc_ticket, authp, &kssl_err);
            enc = kssl_map_enc(kssl_ctx->enctype);
            if (enc == NULL)
                goto err;
# ifdef KSSL_DEBUG
            {
                printf("kssl_cget_tkt rtn %d\n", krb5rc);
                if (krb5rc && kssl_err.text)
                    printf("kssl_cget_tkt kssl_err=%s\n", kssl_err.text);
            }
# endif                         /* KSSL_DEBUG */

            if (krb5rc) {
                ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE, kssl_err.reason);
                goto err;
            }

            /*-
             *   20010406 VRS - Earlier versions used KRB5 AP_REQ
            **  in place of RFC 2712 KerberosWrapper, as in:
            **
            **  Send ticket (copy to *p, set n = length)
            **  n = krb5_ap_req.length;
            **  memcpy(p, krb5_ap_req.data, krb5_ap_req.length);
            **  if (krb5_ap_req.data)
            **    kssl_krb5_free_data_contents(NULL,&krb5_ap_req);
            **
            **  Now using real RFC 2712 KerberosWrapper
            **  (Thanks to Simon Wilkinson <sxw@sxw.org.uk>)
            **  Note: 2712 "opaque" types are here replaced
            **  with a 2-byte length followed by the value.
            **  Example:
            **  KerberosWrapper= xx xx asn1ticket 0 0 xx xx encpms
            **  Where "xx xx" = length bytes.  Shown here with
            **  optional authenticator omitted.
            */

            /*  KerberosWrapper.Ticket              */
            s2n(enc_ticket->length, p);
            memcpy(p, enc_ticket->data, enc_ticket->length);
            p += enc_ticket->length;
            n = enc_ticket->length + 2;

            /*  KerberosWrapper.Authenticator       */
            if (authp && authp->length) {
                s2n(authp->length, p);
                memcpy(p, authp->data, authp->length);
                p += authp->length;
                n += authp->length + 2;

                free(authp->data);
                authp->data = NULL;
                authp->length = 0;
            } else {
                s2n(0, p);      /* null authenticator length */
                n += 2;
            }

            if (RAND_bytes(tmp_buf, sizeof tmp_buf) <= 0)
                goto err;

            /*-
             *  20010420 VRS.  Tried it this way; failed.
             *      EVP_EncryptInit_ex(&ciph_ctx,enc, NULL,NULL);
             *      EVP_CIPHER_CTX_set_key_length(&ciph_ctx,
             *                              kssl_ctx->length);
             *      EVP_EncryptInit_ex(&ciph_ctx,NULL, key,iv);
             */

            memset(iv, 0, sizeof iv); /* per RFC 1510 */
            EVP_EncryptInit_ex(&ciph_ctx, enc, NULL, kssl_ctx->key, iv);
            EVP_EncryptUpdate(&ciph_ctx, epms, &outl, tmp_buf,
                              sizeof tmp_buf);
            EVP_EncryptFinal_ex(&ciph_ctx, &(epms[outl]), &padl);
            outl += padl;
            if (outl > (int)sizeof epms) {
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE,
                       ERR_R_INTERNAL_ERROR);
                goto err;
            }
            EVP_CIPHER_CTX_cleanup(&ciph_ctx);

            /*  KerberosWrapper.EncryptedPreMasterSecret    */
            s2n(outl, p);
            memcpy(p, epms, outl);
            p += outl;
            n += outl + 2;

            s->session->master_key_length =
                s->method->ssl3_enc->generate_master_secret(s,
                                                            s->
                                                            session->master_key,
                                                            tmp_buf,
                                                            sizeof tmp_buf);

            OPENSSL_cleanse(tmp_buf, sizeof tmp_buf);
            OPENSSL_cleanse(epms, outl);
        }
#endif
#ifndef OPENSSL_NO_DH
        else if (alg_k & (SSL_kEDH | SSL_kDHr | SSL_kDHd)) {
            DH *dh_srvr, *dh_clnt;

            if (s->session->sess_cert == NULL) {
                ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE);
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE,
                       SSL_R_UNEXPECTED_MESSAGE);
                goto err;
            }

            if (s->session->sess_cert->peer_dh_tmp != NULL)
                dh_srvr = s->session->sess_cert->peer_dh_tmp;
            else {
                /* we get them from the cert */
                ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE,
                       SSL_R_UNABLE_TO_FIND_DH_PARAMETERS);
                goto err;
            }

            /* generate a new random key */
            if ((dh_clnt = DHparams_dup(dh_srvr)) == NULL) {
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE, ERR_R_DH_LIB);
                goto err;
            }
            if (!DH_generate_key(dh_clnt)) {
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE, ERR_R_DH_LIB);
                goto err;
            }

            /*
             * use the 'p' output buffer for the DH key, but make sure to
             * clear it out afterwards
             */

            n = DH_compute_key(p, dh_srvr->pub_key, dh_clnt);

            if (n <= 0) {
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE, ERR_R_DH_LIB);
                goto err;
            }

            /* generate master key from the result */
            s->session->master_key_length =
                s->method->ssl3_enc->generate_master_secret(s,
                                                            s->
                                                            session->master_key,
                                                            p, n);
            /* clean up */
            memset(p, 0, n);

            /* send off the data */
            n = BN_num_bytes(dh_clnt->pub_key);
            s2n(n, p);
            BN_bn2bin(dh_clnt->pub_key, p);
            n += 2;

            DH_free(dh_clnt);

            /* perhaps clean things up a bit EAY EAY EAY EAY */
        }
#endif
#ifndef OPENSSL_NO_ECDH
        else if (alg_k & (SSL_kEECDH | SSL_kECDHr | SSL_kECDHe)) {
            const EC_GROUP *srvr_group = NULL;
            EC_KEY *tkey;
            int ecdh_clnt_cert = 0;
            int field_size = 0;

            if (s->session->sess_cert == NULL) {
                ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE);
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE,
                       SSL_R_UNEXPECTED_MESSAGE);
                goto err;
            }

            /*
             * Did we send out the client's ECDH share for use in premaster
             * computation as part of client certificate? If so, set
             * ecdh_clnt_cert to 1.
             */
            if ((alg_k & (SSL_kECDHr | SSL_kECDHe)) && (s->cert != NULL)) {
                /*
                 * XXX: For now, we do not support client authentication
                 * using ECDH certificates. To add such support, one needs to
                 * add code that checks for appropriate conditions and sets
                 * ecdh_clnt_cert to 1. For example, the cert have an ECC key
                 * on the same curve as the server's and the key should be
                 * authorized for key agreement. One also needs to add code
                 * in ssl3_connect to skip sending the certificate verify
                 * message. if ((s->cert->key->privatekey != NULL) &&
                 * (s->cert->key->privatekey->type == EVP_PKEY_EC) && ...)
                 * ecdh_clnt_cert = 1;
                 */
            }

            if (s->session->sess_cert->peer_ecdh_tmp != NULL) {
                tkey = s->session->sess_cert->peer_ecdh_tmp;
            } else {
                /* Get the Server Public Key from Cert */
                srvr_pub_pkey =
                    X509_get_pubkey(s->session->
                                    sess_cert->peer_pkeys[SSL_PKEY_ECC].x509);
                if ((srvr_pub_pkey == NULL)
                    || (srvr_pub_pkey->type != EVP_PKEY_EC)
                    || (srvr_pub_pkey->pkey.ec == NULL)) {
                    SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE,
                           ERR_R_INTERNAL_ERROR);
                    goto err;
                }

                tkey = srvr_pub_pkey->pkey.ec;
            }

            srvr_group = EC_KEY_get0_group(tkey);
            srvr_ecpoint = EC_KEY_get0_public_key(tkey);

            if ((srvr_group == NULL) || (srvr_ecpoint == NULL)) {
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE,
                       ERR_R_INTERNAL_ERROR);
                goto err;
            }

            if ((clnt_ecdh = EC_KEY_new()) == NULL) {
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE,
                       ERR_R_MALLOC_FAILURE);
                goto err;
            }

            if (!EC_KEY_set_group(clnt_ecdh, srvr_group)) {
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE, ERR_R_EC_LIB);
                goto err;
            }
            if (ecdh_clnt_cert) {
                /*
                 * Reuse key info from our certificate We only need our
                 * private key to perform the ECDH computation.
                 */
                const BIGNUM *priv_key;
                tkey = s->cert->key->privatekey->pkey.ec;
                priv_key = EC_KEY_get0_private_key(tkey);
                if (priv_key == NULL) {
                    SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE,
                           ERR_R_MALLOC_FAILURE);
                    goto err;
                }
                if (!EC_KEY_set_private_key(clnt_ecdh, priv_key)) {
                    SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE,
                           ERR_R_EC_LIB);
                    goto err;
                }
            } else {
                /* Generate a new ECDH key pair */
                if (!(EC_KEY_generate_key(clnt_ecdh))) {
                    SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE,
                           ERR_R_ECDH_LIB);
                    goto err;
                }
            }

            /*
             * use the 'p' output buffer for the ECDH key, but make sure to
             * clear it out afterwards
             */

            field_size = EC_GROUP_get_degree(srvr_group);
            if (field_size <= 0) {
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE, ERR_R_ECDH_LIB);
                goto err;
            }
            n = ECDH_compute_key(p, (field_size + 7) / 8, srvr_ecpoint,
                                 clnt_ecdh, NULL);
            if (n <= 0) {
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE, ERR_R_ECDH_LIB);
                goto err;
            }

            /* generate master key from the result */
            s->session->master_key_length =
                s->method->ssl3_enc->generate_master_secret(s,
                                                            s->
                                                            session->master_key,
                                                            p, n);

            memset(p, 0, n);    /* clean up */

            if (ecdh_clnt_cert) {
                /* Send empty client key exch message */
                n = 0;
            } else {
                /*
                 * First check the size of encoding and allocate memory
                 * accordingly.
                 */
                encoded_pt_len =
                    EC_POINT_point2oct(srvr_group,
                                       EC_KEY_get0_public_key(clnt_ecdh),
                                       POINT_CONVERSION_UNCOMPRESSED,
                                       NULL, 0, NULL);

                encodedPoint = (unsigned char *)
                    OPENSSL_malloc(encoded_pt_len * sizeof(unsigned char));
                bn_ctx = BN_CTX_new();
                if ((encodedPoint == NULL) || (bn_ctx == NULL)) {
                    SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE,
                           ERR_R_MALLOC_FAILURE);
                    goto err;
                }

                /* Encode the public key */
                n = EC_POINT_point2oct(srvr_group,
                                       EC_KEY_get0_public_key(clnt_ecdh),
                                       POINT_CONVERSION_UNCOMPRESSED,
                                       encodedPoint, encoded_pt_len, bn_ctx);

                *p = n;         /* length of encoded point */
                /* Encoded point will be copied here */
                p += 1;
                /* copy the point */
                memcpy((unsigned char *)p, encodedPoint, n);
                /* increment n to account for length field */
                n += 1;
            }

            /* Free allocated memory */
            BN_CTX_free(bn_ctx);
            if (encodedPoint != NULL)
                OPENSSL_free(encodedPoint);
            if (clnt_ecdh != NULL)
                EC_KEY_free(clnt_ecdh);
            EVP_PKEY_free(srvr_pub_pkey);
        }
#endif                          /* !OPENSSL_NO_ECDH */

#ifndef OPENSSL_NO_PSK
        else if (alg_k & SSL_kPSK) {
            char identity[PSK_MAX_IDENTITY_LEN];
            unsigned char *t = NULL;
            unsigned char psk_or_pre_ms[PSK_MAX_PSK_LEN * 2 + 4];
            unsigned int pre_ms_len = 0, psk_len = 0;
            int psk_err = 1;

            n = 0;
            if (s->psk_client_callback == NULL) {
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE,
                       SSL_R_PSK_NO_CLIENT_CB);
                goto err;
            }

            psk_len = s->psk_client_callback(s, s->ctx->psk_identity_hint,
                                             identity, PSK_MAX_IDENTITY_LEN,
                                             psk_or_pre_ms,
                                             sizeof(psk_or_pre_ms));
            if (psk_len > PSK_MAX_PSK_LEN) {
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE,
                       ERR_R_INTERNAL_ERROR);
                goto psk_err;
            } else if (psk_len == 0) {
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE,
                       SSL_R_PSK_IDENTITY_NOT_FOUND);
                goto psk_err;
            }

            /* create PSK pre_master_secret */
            pre_ms_len = 2 + psk_len + 2 + psk_len;
            t = psk_or_pre_ms;
            memmove(psk_or_pre_ms + psk_len + 4, psk_or_pre_ms, psk_len);
            s2n(psk_len, t);
            memset(t, 0, psk_len);
            t += psk_len;
            s2n(psk_len, t);

            if (s->session->psk_identity_hint != NULL)
                OPENSSL_free(s->session->psk_identity_hint);
            s->session->psk_identity_hint =
                BUF_strdup(s->ctx->psk_identity_hint);
            if (s->ctx->psk_identity_hint != NULL
                && s->session->psk_identity_hint == NULL) {
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE,
                       ERR_R_MALLOC_FAILURE);
                goto psk_err;
            }

            if (s->session->psk_identity != NULL)
                OPENSSL_free(s->session->psk_identity);
            s->session->psk_identity = BUF_strdup(identity);
            if (s->session->psk_identity == NULL) {
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE,
                       ERR_R_MALLOC_FAILURE);
                goto psk_err;
            }

            s->session->master_key_length =
                s->method->ssl3_enc->generate_master_secret(s,
                                                            s->
                                                            session->master_key,
                                                            psk_or_pre_ms,
                                                            pre_ms_len);
            n = strlen(identity);
            s2n(n, p);
            memcpy(p, identity, n);
            n += 2;
            psk_err = 0;
 psk_err:
            OPENSSL_cleanse(identity, PSK_MAX_IDENTITY_LEN);
            OPENSSL_cleanse(psk_or_pre_ms, sizeof(psk_or_pre_ms));
            if (psk_err != 0) {
                ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
                goto err;
            }
        }
#endif
        else {
            ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
            SSLerr(SSL_F_DTLS1_SEND_CLIENT_KEY_EXCHANGE,
                   ERR_R_INTERNAL_ERROR);
            goto err;
        }

        d = dtls1_set_message_header(s, d,
                                     SSL3_MT_CLIENT_KEY_EXCHANGE, n, 0, n);
        /*-
         *(d++)=SSL3_MT_CLIENT_KEY_EXCHANGE;
         l2n3(n,d);
         l2n(s->d1->handshake_write_seq,d);
         s->d1->handshake_write_seq++;
        */

        s->state = SSL3_ST_CW_KEY_EXCH_B;
        /* number of bytes to write */
        s->init_num = n + DTLS1_HM_HEADER_LENGTH;
        s->init_off = 0;

        /* buffer the message to handle re-xmits */
        dtls1_buffer_message(s, 0);
    }

    /* SSL3_ST_CW_KEY_EXCH_B */
    return (dtls1_do_write(s, SSL3_RT_HANDSHAKE));
 err:
#ifndef OPENSSL_NO_ECDH
    BN_CTX_free(bn_ctx);
    if (encodedPoint != NULL)
        OPENSSL_free(encodedPoint);
    if (clnt_ecdh != NULL)
        EC_KEY_free(clnt_ecdh);
    EVP_PKEY_free(srvr_pub_pkey);
#endif
    return (-1);
}

int dtls1_send_client_verify(SSL *s)
{
    unsigned char *p, *d;
    unsigned char data[MD5_DIGEST_LENGTH + SHA_DIGEST_LENGTH];
    EVP_PKEY *pkey;
#ifndef OPENSSL_NO_RSA
    unsigned u = 0;
#endif
    unsigned long n;
#if !defined(OPENSSL_NO_DSA) || !defined(OPENSSL_NO_ECDSA)
    int j;
#endif

    if (s->state == SSL3_ST_CW_CERT_VRFY_A) {
        d = (unsigned char *)s->init_buf->data;
        p = &(d[DTLS1_HM_HEADER_LENGTH]);
        pkey = s->cert->key->privatekey;

        s->method->ssl3_enc->cert_verify_mac(s,
                                             NID_sha1,
                                             &(data[MD5_DIGEST_LENGTH]));

#ifndef OPENSSL_NO_RSA
        if (pkey->type == EVP_PKEY_RSA) {
            s->method->ssl3_enc->cert_verify_mac(s, NID_md5, &(data[0]));
            if (RSA_sign(NID_md5_sha1, data,
                         MD5_DIGEST_LENGTH + SHA_DIGEST_LENGTH,
                         &(p[2]), &u, pkey->pkey.rsa) <= 0) {
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_VERIFY, ERR_R_RSA_LIB);
                goto err;
            }
            s2n(u, p);
            n = u + 2;
        } else
#endif
#ifndef OPENSSL_NO_DSA
        if (pkey->type == EVP_PKEY_DSA) {
            if (!DSA_sign(pkey->save_type,
                          &(data[MD5_DIGEST_LENGTH]),
                          SHA_DIGEST_LENGTH, &(p[2]),
                          (unsigned int *)&j, pkey->pkey.dsa)) {
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_VERIFY, ERR_R_DSA_LIB);
                goto err;
            }
            s2n(j, p);
            n = j + 2;
        } else
#endif
#ifndef OPENSSL_NO_ECDSA
        if (pkey->type == EVP_PKEY_EC) {
            if (!ECDSA_sign(pkey->save_type,
                            &(data[MD5_DIGEST_LENGTH]),
                            SHA_DIGEST_LENGTH, &(p[2]),
                            (unsigned int *)&j, pkey->pkey.ec)) {
                SSLerr(SSL_F_DTLS1_SEND_CLIENT_VERIFY, ERR_R_ECDSA_LIB);
                goto err;
            }
            s2n(j, p);
            n = j + 2;
        } else
#endif
        {
            SSLerr(SSL_F_DTLS1_SEND_CLIENT_VERIFY, ERR_R_INTERNAL_ERROR);
            goto err;
        }

        d = dtls1_set_message_header(s, d,
                                     SSL3_MT_CERTIFICATE_VERIFY, n, 0, n);

        s->init_num = (int)n + DTLS1_HM_HEADER_LENGTH;
        s->init_off = 0;

        /* buffer the message to handle re-xmits */
        dtls1_buffer_message(s, 0);

        s->state = SSL3_ST_CW_CERT_VRFY_B;
    }

    /* s->state = SSL3_ST_CW_CERT_VRFY_B */
    return (dtls1_do_write(s, SSL3_RT_HANDSHAKE));
 err:
    return (-1);
}

int dtls1_send_client_certificate(SSL *s)
{
    X509 *x509 = NULL;
    EVP_PKEY *pkey = NULL;
    int i;
    unsigned long l;

    if (s->state == SSL3_ST_CW_CERT_A) {
        if ((s->cert == NULL) ||
            (s->cert->key->x509 == NULL) ||
            (s->cert->key->privatekey == NULL))
            s->state = SSL3_ST_CW_CERT_B;
        else
            s->state = SSL3_ST_CW_CERT_C;
    }

    /* We need to get a client cert */
    if (s->state == SSL3_ST_CW_CERT_B) {
        /*
         * If we get an error, we need to ssl->rwstate=SSL_X509_LOOKUP;
         * return(-1); We then get retied later
         */
        i = 0;
        i = ssl_do_client_cert_cb(s, &x509, &pkey);
        if (i < 0) {
            s->rwstate = SSL_X509_LOOKUP;
            return (-1);
        }
        s->rwstate = SSL_NOTHING;
        if ((i == 1) && (pkey != NULL) && (x509 != NULL)) {
            s->state = SSL3_ST_CW_CERT_B;
            if (!SSL_use_certificate(s, x509) || !SSL_use_PrivateKey(s, pkey))
                i = 0;
        } else if (i == 1) {
            i = 0;
            SSLerr(SSL_F_DTLS1_SEND_CLIENT_CERTIFICATE,
                   SSL_R_BAD_DATA_RETURNED_BY_CALLBACK);
        }

        if (x509 != NULL)
            X509_free(x509);
        if (pkey != NULL)
            EVP_PKEY_free(pkey);
        if (i == 0) {
            if (s->version == SSL3_VERSION) {
                s->s3->tmp.cert_req = 0;
                ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_CERTIFICATE);
                return (1);
            } else {
                s->s3->tmp.cert_req = 2;
            }
        }

        /* Ok, we have a cert */
        s->state = SSL3_ST_CW_CERT_C;
    }

    if (s->state == SSL3_ST_CW_CERT_C) {
        s->state = SSL3_ST_CW_CERT_D;
        l = dtls1_output_cert_chain(s,
                                    (s->s3->tmp.cert_req ==
                                     2) ? NULL : s->cert->key->x509);
        if (!l) {
            SSLerr(SSL_F_DTLS1_SEND_CLIENT_CERTIFICATE, ERR_R_INTERNAL_ERROR);
            ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
            return 0;
        }
        s->init_num = (int)l;
        s->init_off = 0;

        /* set header called by dtls1_output_cert_chain() */

        /* buffer the message to handle re-xmits */
        dtls1_buffer_message(s, 0);
    }
    /* SSL3_ST_CW_CERT_D */
    return (dtls1_do_write(s, SSL3_RT_HANDSHAKE));
}