Get correct GOST private key instead of just assuming the last one is

[thirdparty/openssl.git] / ssl / s3_srvr.c

/* ssl/s3_srvr.c -*- mode:C; c-file-style: "eay" -*- */
/* 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.]
 */
/* ====================================================================
 * Copyright (c) 1998-2007 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 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
 *
 * Portions of the attached software ("Contribution") are developed by 
 * SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project.
 *
 * The Contribution is licensed pursuant to the OpenSSL open source
 * license provided above.
 *
 * ECC cipher suite support in OpenSSL originally written by
 * Vipul Gupta and Sumit Gupta of Sun Microsystems Laboratories.
 *
 */
/* ====================================================================
 * Copyright 2005 Nokia. All rights reserved.
 *
 * The portions of the attached software ("Contribution") is developed by
 * Nokia Corporation and is licensed pursuant to the OpenSSL open source
 * license.
 *
 * The Contribution, originally written by Mika Kousa and Pasi Eronen of
 * Nokia Corporation, consists of the "PSK" (Pre-Shared Key) ciphersuites
 * support (see RFC 4279) to OpenSSL.
 *
 * No patent licenses or other rights except those expressly stated in
 * the OpenSSL open source license shall be deemed granted or received
 * expressly, by implication, estoppel, or otherwise.
 *
 * No assurances are provided by Nokia that the Contribution does not
 * infringe the patent or other intellectual property rights of any third
 * party or that the license provides you with all the necessary rights
 * to make use of the Contribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. IN
 * ADDITION TO THE DISCLAIMERS INCLUDED IN THE LICENSE, NOKIA
 * SPECIFICALLY DISCLAIMS ANY LIABILITY FOR CLAIMS BROUGHT BY YOU OR ANY
 * OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS OR
 * OTHERWISE.
 */

#define REUSE_CIPHER_BUG
#define NETSCAPE_HANG_BUG

#include <stdio.h>
#include "ssl_locl.h"
#include "kssl_lcl.h"
#include <openssl/buffer.h>
#include <openssl/rand.h>
#include <openssl/objects.h>
#include <openssl/evp.h>
#include <openssl/hmac.h>
#include <openssl/x509.h>
#ifndef OPENSSL_NO_DH
#include <openssl/dh.h>
#endif
#include <openssl/bn.h>
#ifndef OPENSSL_NO_KRB5
#include <openssl/krb5_asn.h>
#endif
#include <openssl/md5.h>

static const SSL_METHOD *ssl3_get_server_method(int ver);

static const SSL_METHOD *ssl3_get_server_method(int ver)
        {
        if (ver == SSL3_VERSION)
                return(SSLv3_server_method());
        else
                return(NULL);
        }

IMPLEMENT_ssl3_meth_func(SSLv3_server_method,
                        ssl3_accept,
                        ssl_undefined_function,
                        ssl3_get_server_method)

int ssl3_accept(SSL *s)
        {
        BUF_MEM *buf;
        unsigned long alg_k,Time=(unsigned long)time(NULL);
        void (*cb)(const SSL *ssl,int type,int val)=NULL;
        int ret= -1;
        int new_state,state,skip=0;

        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;

        /* init things to blank */
        s->in_handshake++;
        if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);

        if (s->cert == NULL)
                {
                SSLerr(SSL_F_SSL3_ACCEPT,SSL_R_NO_CERTIFICATE_SET);
                return(-1);
                }

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

                switch (s->state)
                        {
                case SSL_ST_RENEGOTIATE:
                        s->renegotiate=1;
                        /* s->state=SSL_ST_ACCEPT; */

                case SSL_ST_BEFORE:
                case SSL_ST_ACCEPT:
                case SSL_ST_BEFORE|SSL_ST_ACCEPT:
                case SSL_ST_OK|SSL_ST_ACCEPT:

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

                        if ((s->version>>8) != 3)
                                {
                                SSLerr(SSL_F_SSL3_ACCEPT, ERR_R_INTERNAL_ERROR);
                                return -1;
                                }
                        s->type=SSL_ST_ACCEPT;

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

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

                        s->init_num=0;

                        if (s->state != SSL_ST_RENEGOTIATE)
                                {
                                /* Ok, we now need to push on a buffering BIO so that
                                 * the output is sent in a way that TCP likes :-)
                                 */
                                if (!ssl_init_wbio_buffer(s,1)) { ret= -1; goto end; }
                                
                                ssl3_init_finished_mac(s);
                                s->state=SSL3_ST_SR_CLNT_HELLO_A;
                                s->ctx->stats.sess_accept++;
                                }
                        else if (!s->s3->send_connection_binding &&
                                !(s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
                                {
                                /* Server attempting to renegotiate with
                                 * client that doesn't support secure
                                 * renegotiation.
                                 */
                                SSLerr(SSL_F_SSL3_ACCEPT, SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
                                ssl3_send_alert(s,SSL3_AL_FATAL,SSL_AD_HANDSHAKE_FAILURE);
                                ret = -1;
                                goto end;
                                }
                        else
                                {
                                /* s->state == SSL_ST_RENEGOTIATE,
                                 * we will just send a HelloRequest */
                                s->ctx->stats.sess_accept_renegotiate++;
                                s->state=SSL3_ST_SW_HELLO_REQ_A;
                                }
                        break;

                case SSL3_ST_SW_HELLO_REQ_A:
                case SSL3_ST_SW_HELLO_REQ_B:

                        s->shutdown=0;
                        ret=ssl3_send_hello_request(s);
                        if (ret <= 0) goto end;
                        s->s3->tmp.next_state=SSL3_ST_SW_HELLO_REQ_C;
                        s->state=SSL3_ST_SW_FLUSH;
                        s->init_num=0;

                        ssl3_init_finished_mac(s);
                        break;

                case SSL3_ST_SW_HELLO_REQ_C:
                        s->state=SSL_ST_OK;
                        break;

                case SSL3_ST_SR_CLNT_HELLO_A:
                case SSL3_ST_SR_CLNT_HELLO_B:
                case SSL3_ST_SR_CLNT_HELLO_C:

                        s->shutdown=0;
                        ret=ssl3_get_client_hello(s);
                        if (ret <= 0) goto end;
                        
                        s->renegotiate = 2;
                        s->state=SSL3_ST_SW_SRVR_HELLO_A;
                        s->init_num=0;
                        break;

                case SSL3_ST_SW_SRVR_HELLO_A:
                case SSL3_ST_SW_SRVR_HELLO_B:
                        ret=ssl3_send_server_hello(s);
                        if (ret <= 0) goto end;
#ifndef OPENSSL_NO_TLSEXT
                        if (s->hit)
                                {
                                if (s->tlsext_ticket_expected)
                                        s->state=SSL3_ST_SW_SESSION_TICKET_A;
                                else
                                        s->state=SSL3_ST_SW_CHANGE_A;
                                }
#else
                        if (s->hit)
                                        s->state=SSL3_ST_SW_CHANGE_A;
#endif
                        else
                                s->state=SSL3_ST_SW_CERT_A;
                        s->init_num=0;
                        break;

                case SSL3_ST_SW_CERT_A:
                case SSL3_ST_SW_CERT_B:
                        /* Check if it is anon DH or anon ECDH, */
                        /* normal PSK or KRB5 */
                        if (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL)
                                && !(s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK)
                                && !(s->s3->tmp.new_cipher->algorithm_auth & SSL_aKRB5))
                                {
                                ret=ssl3_send_server_certificate(s);
                                if (ret <= 0) goto end;
#ifndef OPENSSL_NO_TLSEXT
                                if (s->tlsext_status_expected)
                                        s->state=SSL3_ST_SW_CERT_STATUS_A;
                                else
                                        s->state=SSL3_ST_SW_KEY_EXCH_A;
                                }
                        else
                                {
                                skip = 1;
                                s->state=SSL3_ST_SW_KEY_EXCH_A;
                                }
#else
                                }
                        else
                                skip=1;

                        s->state=SSL3_ST_SW_KEY_EXCH_A;
#endif
                        s->init_num=0;
                        break;

                case SSL3_ST_SW_KEY_EXCH_A:
                case SSL3_ST_SW_KEY_EXCH_B:
                        alg_k = s->s3->tmp.new_cipher->algorithm_mkey;

                        /* clear this, it may get reset by
                         * send_server_key_exchange */
                        if ((s->options & SSL_OP_EPHEMERAL_RSA)
#ifndef OPENSSL_NO_KRB5
                                && !(alg_k & SSL_kKRB5)
#endif /* OPENSSL_NO_KRB5 */
                                )
                                /* option SSL_OP_EPHEMERAL_RSA sends temporary RSA key
                                 * even when forbidden by protocol specs
                                 * (handshake may fail as clients are not required to
                                 * be able to handle this) */
                                s->s3->tmp.use_rsa_tmp=1;
                        else
                                s->s3->tmp.use_rsa_tmp=0;


                        /* only send if a DH key exchange, fortezza or
                         * RSA but we have a sign only certificate
                         *
                         * PSK: may send PSK identity hints
                         *
                         * For ECC ciphersuites, we send a serverKeyExchange
                         * message only if the cipher suite is either
                         * ECDH-anon or ECDHE. In other cases, the
                         * server certificate contains the server's
                         * public key for key exchange.
                         */
                        if (s->s3->tmp.use_rsa_tmp
                        /* PSK: send ServerKeyExchange if PSK identity
                         * hint if provided */
#ifndef OPENSSL_NO_PSK
                            || ((alg_k & SSL_kPSK) && s->ctx->psk_identity_hint)
#endif
                            || (alg_k & (SSL_kDHr|SSL_kDHd|SSL_kEDH))
                            || (alg_k & SSL_kEECDH)
                            || ((alg_k & SSL_kRSA)
                                && (s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey == NULL
                                    || (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher)
                                        && EVP_PKEY_size(s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey)*8 > SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher)
                                        )
                                    )
                                )
                            )
                                {
                                ret=ssl3_send_server_key_exchange(s);
                                if (ret <= 0) goto end;
                                }
                        else
                                skip=1;

                        s->state=SSL3_ST_SW_CERT_REQ_A;
                        s->init_num=0;
                        break;

                case SSL3_ST_SW_CERT_REQ_A:
                case SSL3_ST_SW_CERT_REQ_B:
                        if (/* don't request cert unless asked for it: */
                                !(s->verify_mode & SSL_VERIFY_PEER) ||
                                /* if SSL_VERIFY_CLIENT_ONCE is set,
                                 * don't request cert during re-negotiation: */
                                ((s->session->peer != NULL) &&
                                 (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) ||
                                /* never request cert in anonymous ciphersuites
                                 * (see section "Certificate request" in SSL 3 drafts
                                 * and in RFC 2246): */
                                ((s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL) &&
                                 /* ... except when the application insists on verification
                                  * (against the specs, but s3_clnt.c accepts this for SSL 3) */
                                 !(s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) ||
                                 /* never request cert in Kerberos ciphersuites */
                                (s->s3->tmp.new_cipher->algorithm_auth & SSL_aKRB5)
                                /* With normal PSK Certificates and
                                 * Certificate Requests are omitted */
                                || (s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK))
                                {
                                /* no cert request */
                                skip=1;
                                s->s3->tmp.cert_request=0;
                                s->state=SSL3_ST_SW_SRVR_DONE_A;
                                }
                        else
                                {
                                s->s3->tmp.cert_request=1;
                                ret=ssl3_send_certificate_request(s);
                                if (ret <= 0) goto end;
#ifndef NETSCAPE_HANG_BUG
                                s->state=SSL3_ST_SW_SRVR_DONE_A;
#else
                                s->state=SSL3_ST_SW_FLUSH;
                                s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
#endif
                                s->init_num=0;
                                }
                        break;

                case SSL3_ST_SW_SRVR_DONE_A:
                case SSL3_ST_SW_SRVR_DONE_B:
                        ret=ssl3_send_server_done(s);
                        if (ret <= 0) goto end;
                        s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
                        s->state=SSL3_ST_SW_FLUSH;
                        s->init_num=0;
                        break;
                
                case SSL3_ST_SW_FLUSH:

                        /* This code originally checked to see if
                         * any data was pending using BIO_CTRL_INFO
                         * and then flushed. This caused problems
                         * as documented in PR#1939. The proposed
                         * fix doesn't completely resolve this issue
                         * as buggy implementations of BIO_CTRL_PENDING
                         * still exist. So instead we just flush
                         * unconditionally.
                         */

                        s->rwstate=SSL_WRITING;
                        if (BIO_flush(s->wbio) <= 0)
                                {
                                ret= -1;
                                goto end;
                                }
                        s->rwstate=SSL_NOTHING;

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

                case SSL3_ST_SR_CERT_A:
                case SSL3_ST_SR_CERT_B:
                        /* Check for second client hello (MS SGC) */
                        ret = ssl3_check_client_hello(s);
                        if (ret <= 0)
                                goto end;
                        if (ret == 2)
                                s->state = SSL3_ST_SR_CLNT_HELLO_C;
                        else {
                                if (s->s3->tmp.cert_request)
                                        {
                                        ret=ssl3_get_client_certificate(s);
                                        if (ret <= 0) goto end;
                                        }
                                s->init_num=0;
                                s->state=SSL3_ST_SR_KEY_EXCH_A;
                        }
                        break;

                case SSL3_ST_SR_KEY_EXCH_A:
                case SSL3_ST_SR_KEY_EXCH_B:
                        ret=ssl3_get_client_key_exchange(s);
                        if (ret <= 0)
                                goto end;
                        if (ret == 2)
                                {
                                /* For the ECDH ciphersuites when
                                 * the client sends its ECDH pub key in
                                 * a certificate, the CertificateVerify
                                 * message is not sent.
                                 * Also for GOST ciphersuites when
                                 * the client uses its key from the certificate
                                 * for key exchange.
                                 */
#if defined(OPENSSL_NO_TLSEXT) || defined(OPENSSL_NO_NEXTPROTONEG)
                                s->state=SSL3_ST_SR_FINISHED_A;
#else
                                if (s->s3->next_proto_neg_seen)
                                        s->state=SSL3_ST_SR_NEXT_PROTO_A;
                                else
                                        s->state=SSL3_ST_SR_FINISHED_A;
#endif
                                s->init_num = 0;
                                }
                        else
                                {
                                int offset=0;
                                int dgst_num;

                                s->state=SSL3_ST_SR_CERT_VRFY_A;
                                s->init_num=0;

                                /* We need to get hashes here so if there is
                                 * a client cert, it can be verified
                                 * FIXME - digest processing for CertificateVerify
                                 * should be generalized. But it is next step
                                 */
                                if (s->s3->handshake_buffer)
                                        if (!ssl3_digest_cached_records(s))
                                                return -1;
                                for (dgst_num=0; dgst_num<SSL_MAX_DIGEST;dgst_num++)    
                                        if (s->s3->handshake_dgst[dgst_num]) 
                                                {
                                                int dgst_size;

                                                s->method->ssl3_enc->cert_verify_mac(s,EVP_MD_CTX_type(s->s3->handshake_dgst[dgst_num]),&(s->s3->tmp.cert_verify_md[offset]));
                                                dgst_size=EVP_MD_CTX_size(s->s3->handshake_dgst[dgst_num]);
                                                if (dgst_size < 0)
                                                        {
                                                        ret = -1;
                                                        goto end;
                                                        }
                                                offset+=dgst_size;
                                                }               
                                }
                        break;

                case SSL3_ST_SR_CERT_VRFY_A:
                case SSL3_ST_SR_CERT_VRFY_B:

                        /* we should decide if we expected this one */
                        ret=ssl3_get_cert_verify(s);
                        if (ret <= 0) goto end;

#if defined(OPENSSL_NO_TLSEXT) || defined(OPENSSL_NO_NEXTPROTONEG)
                        s->state=SSL3_ST_SR_FINISHED_A;
#else
                        if (s->s3->next_proto_neg_seen)
                                s->state=SSL3_ST_SR_NEXT_PROTO_A;
                        else
                                s->state=SSL3_ST_SR_FINISHED_A;
#endif
                        s->init_num=0;
                        break;

#if !defined(OPENSSL_NO_TLSEXT) && !defined(OPENSSL_NO_NEXTPROTONEG)
                case SSL3_ST_SR_NEXT_PROTO_A:
                case SSL3_ST_SR_NEXT_PROTO_B:
                        ret=ssl3_get_next_proto(s);
                        if (ret <= 0) goto end;
                        s->init_num = 0;
                        s->state=SSL3_ST_SR_FINISHED_A;
                        break;
#endif

                case SSL3_ST_SR_FINISHED_A:
                case SSL3_ST_SR_FINISHED_B:
                        ret=ssl3_get_finished(s,SSL3_ST_SR_FINISHED_A,
                                SSL3_ST_SR_FINISHED_B);
                        if (ret <= 0) goto end;
#ifndef OPENSSL_NO_TLSEXT
                        if (s->tlsext_ticket_expected)
                                s->state=SSL3_ST_SW_SESSION_TICKET_A;
                        else if (s->hit)
                                s->state=SSL_ST_OK;
#else
                        if (s->hit)
                                s->state=SSL_ST_OK;
#endif
                        else
                                s->state=SSL3_ST_SW_CHANGE_A;
                        s->init_num=0;
                        break;

#ifndef OPENSSL_NO_TLSEXT
                case SSL3_ST_SW_SESSION_TICKET_A:
                case SSL3_ST_SW_SESSION_TICKET_B:
                        ret=ssl3_send_newsession_ticket(s);
                        if (ret <= 0) goto end;
                        s->state=SSL3_ST_SW_CHANGE_A;
                        s->init_num=0;
                        break;

                case SSL3_ST_SW_CERT_STATUS_A:
                case SSL3_ST_SW_CERT_STATUS_B:
                        ret=ssl3_send_cert_status(s);
                        if (ret <= 0) goto end;
                        s->state=SSL3_ST_SW_KEY_EXCH_A;
                        s->init_num=0;
                        break;

#endif

                case SSL3_ST_SW_CHANGE_A:
                case SSL3_ST_SW_CHANGE_B:

                        s->session->cipher=s->s3->tmp.new_cipher;
                        if (!s->method->ssl3_enc->setup_key_block(s))
                                { ret= -1; goto end; }

                        ret=ssl3_send_change_cipher_spec(s,
                                SSL3_ST_SW_CHANGE_A,SSL3_ST_SW_CHANGE_B);

                        if (ret <= 0) goto end;
                        s->state=SSL3_ST_SW_FINISHED_A;
                        s->init_num=0;

                        if (!s->method->ssl3_enc->change_cipher_state(s,
                                SSL3_CHANGE_CIPHER_SERVER_WRITE))
                                {
                                ret= -1;
                                goto end;
                                }

                        break;

                case SSL3_ST_SW_FINISHED_A:
                case SSL3_ST_SW_FINISHED_B:
                        ret=ssl3_send_finished(s,
                                SSL3_ST_SW_FINISHED_A,SSL3_ST_SW_FINISHED_B,
                                s->method->ssl3_enc->server_finished_label,
                                s->method->ssl3_enc->server_finished_label_len);
                        if (ret <= 0) goto end;
                        s->state=SSL3_ST_SW_FLUSH;
                        if (s->hit)
                                {
#if defined(OPENSSL_NO_TLSEXT) || defined(OPENSSL_NO_NEXTPROTONEG)
                                s->s3->tmp.next_state=SSL3_ST_SR_FINISHED_A;
#else
                                if (s->s3->next_proto_neg_seen)
                                        s->s3->tmp.next_state=SSL3_ST_SR_NEXT_PROTO_A;
                                else
                                        s->s3->tmp.next_state=SSL3_ST_SR_FINISHED_A;
#endif
                                }
                        else
                                s->s3->tmp.next_state=SSL_ST_OK;
                        s->init_num=0;
                        break;

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

                        BUF_MEM_free(s->init_buf);
                        s->init_buf=NULL;

                        /* remove buffering on output */
                        ssl_free_wbio_buffer(s);

                        s->init_num=0;

                        if (s->renegotiate == 2) /* skipped if we just sent a HelloRequest */
                                {
                                /* actually not necessarily a 'new' session unless
                                 * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION is set */
                                
                                s->renegotiate=0;
                                s->new_session=0;
                                
                                ssl_update_cache(s,SSL_SESS_CACHE_SERVER);
                                
                                s->ctx->stats.sess_accept_good++;
                                /* s->server=1; */
                                s->handshake_func=ssl3_accept;

                                if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_DONE,1);
                                }
                        
                        ret = 1;
                        goto end;
                        /* break; */

                default:
                        SSLerr(SSL_F_SSL3_ACCEPT,SSL_R_UNKNOWN_STATE);
                        ret= -1;
                        goto end;
                        /* break; */
                        }
                
                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_ACCEPT_LOOP,1);
                                s->state=new_state;
                                }
                        }
                skip=0;
                }
end:
        /* BIO_flush(s->wbio); */

        s->in_handshake--;
        if (cb != NULL)
                cb(s,SSL_CB_ACCEPT_EXIT,ret);
        return(ret);
        }

int ssl3_send_hello_request(SSL *s)
        {
        unsigned char *p;

        if (s->state == SSL3_ST_SW_HELLO_REQ_A)
                {
                p=(unsigned char *)s->init_buf->data;
                *(p++)=SSL3_MT_HELLO_REQUEST;
                *(p++)=0;
                *(p++)=0;
                *(p++)=0;

                s->state=SSL3_ST_SW_HELLO_REQ_B;
                /* number of bytes to write */
                s->init_num=4;
                s->init_off=0;
                }

        /* SSL3_ST_SW_HELLO_REQ_B */
        return(ssl3_do_write(s,SSL3_RT_HANDSHAKE));
        }

int ssl3_check_client_hello(SSL *s)
        {
        int ok;
        long n;

        /* this function is called when we really expect a Certificate message,
         * so permit appropriate message length */
        n=s->method->ssl_get_message(s,
                SSL3_ST_SR_CERT_A,
                SSL3_ST_SR_CERT_B,
                -1,
                s->max_cert_list,
                &ok);
        if (!ok) return((int)n);
        s->s3->tmp.reuse_message = 1;
        if (s->s3->tmp.message_type == SSL3_MT_CLIENT_HELLO)
                {
                /* Throw away what we have done so far in the current handshake,
                 * which will now be aborted. (A full SSL_clear would be too much.)
                 * I hope that tmp.dh is the only thing that may need to be cleared
                 * when a handshake is not completed ... */
#ifndef OPENSSL_NO_DH
                if (s->s3->tmp.dh != NULL)
                        {
                        DH_free(s->s3->tmp.dh);
                        s->s3->tmp.dh = NULL;
                        }
#endif
                return 2;
                }
        return 1;
}

int ssl3_get_client_hello(SSL *s)
        {
        int i,j,ok,al,ret= -1;
        unsigned int cookie_len;
        long n;
        unsigned long id;
        unsigned char *p,*d,*q;
        SSL_CIPHER *c;
#ifndef OPENSSL_NO_COMP
        SSL_COMP *comp=NULL;
#endif
        STACK_OF(SSL_CIPHER) *ciphers=NULL;

        /* We do this so that we will respond with our native type.
         * If we are TLSv1 and we get SSLv3, we will respond with TLSv1,
         * This down switching should be handled by a different method.
         * If we are SSLv3, we will respond with SSLv3, even if prompted with
         * TLSv1.
         */
        if (s->state == SSL3_ST_SR_CLNT_HELLO_A)
                {
                s->state=SSL3_ST_SR_CLNT_HELLO_B;
                }
        s->first_packet=1;
        n=s->method->ssl_get_message(s,
                SSL3_ST_SR_CLNT_HELLO_B,
                SSL3_ST_SR_CLNT_HELLO_C,
                SSL3_MT_CLIENT_HELLO,
                SSL3_RT_MAX_PLAIN_LENGTH,
                &ok);

        if (!ok) return((int)n);
        s->first_packet=0;
        d=p=(unsigned char *)s->init_msg;

        /* use version from inside client hello, not from record header
         * (may differ: see RFC 2246, Appendix E, second paragraph) */
        s->client_version=(((int)p[0])<<8)|(int)p[1];
        p+=2;

        if ((s->version == DTLS1_VERSION && s->client_version > s->version) ||
            (s->version != DTLS1_VERSION && s->client_version < s->version))
                {
                SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_WRONG_VERSION_NUMBER);
                if ((s->client_version>>8) == SSL3_VERSION_MAJOR)
                        {
                        /* similar to ssl3_get_record, send alert using remote version number */
                        s->version = s->client_version;
                        }
                al = SSL_AD_PROTOCOL_VERSION;
                goto f_err;
                }

        /* If we require cookies and this ClientHello doesn't
         * contain one, just return since we do not want to
         * allocate any memory yet. So check cookie length...
         */
        if (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE)
                {
                unsigned int session_length, cookie_length;
                
                session_length = *(p + SSL3_RANDOM_SIZE);
                cookie_length = *(p + SSL3_RANDOM_SIZE + session_length + 1);

                if (cookie_length == 0)
                        return 1;
                }

        /* load the client random */
        memcpy(s->s3->client_random,p,SSL3_RANDOM_SIZE);
        p+=SSL3_RANDOM_SIZE;

        /* get the session-id */
        j= *(p++);

        s->hit=0;
        /* Versions before 0.9.7 always allow session reuse during renegotiation
         * (i.e. when s->new_session is true), option
         * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION is new with 0.9.7.
         * Maybe this optional behaviour should always have been the default,
         * but we cannot safely change the default behaviour (or new applications
         * might be written that become totally unsecure when compiled with
         * an earlier library version)
         */
        if ((s->new_session && (s->options & SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION)))
                {
                if (!ssl_get_new_session(s,1))
                        goto err;
                }
        else
                {
                i=ssl_get_prev_session(s, p, j, d + n);
                if (i == 1)
                        { /* previous session */
                        s->hit=1;
                        }
                else if (i == -1)
                        goto err;
                else /* i == 0 */
                        {
                        if (!ssl_get_new_session(s,1))
                                goto err;
                        }
                }

        p+=j;

        if (s->version == DTLS1_VERSION || s->version == DTLS1_BAD_VER)
                {
                /* cookie stuff */
                cookie_len = *(p++);

                /* 
                 * The ClientHello may contain a cookie even if the
                 * HelloVerify message has not been sent--make sure that it
                 * does not cause an overflow.
                 */
                if ( cookie_len > sizeof(s->d1->rcvd_cookie))
                        {
                        /* too much data */
                        al = SSL_AD_DECODE_ERROR;
                        SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_COOKIE_MISMATCH);
                        goto f_err;
                        }

                /* verify the cookie if appropriate option is set. */
                if ((SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) &&
                        cookie_len > 0)
                        {
                        memcpy(s->d1->rcvd_cookie, p, cookie_len);

                        if ( s->ctx->app_verify_cookie_cb != NULL)
                                {
                                if ( s->ctx->app_verify_cookie_cb(s, s->d1->rcvd_cookie,
                                        cookie_len) == 0)
                                        {
                                        al=SSL_AD_HANDSHAKE_FAILURE;
                                        SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, 
                                                SSL_R_COOKIE_MISMATCH);
                                        goto f_err;
                                        }
                                /* else cookie verification succeeded */
                                }
                        else if ( memcmp(s->d1->rcvd_cookie, s->d1->cookie, 
                                                  s->d1->cookie_len) != 0) /* default verification */
                                {
                                        al=SSL_AD_HANDSHAKE_FAILURE;
                                        SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, 
                                                SSL_R_COOKIE_MISMATCH);
                                        goto f_err;
                                }

                        ret = 2;
                        }

                p += cookie_len;
                }

        n2s(p,i);
        if ((i == 0) && (j != 0))
                {
                /* we need a cipher if we are not resuming a session */
                al=SSL_AD_ILLEGAL_PARAMETER;
                SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_NO_CIPHERS_SPECIFIED);
                goto f_err;
                }
        if ((p+i) >= (d+n))
                {
                /* not enough data */
                al=SSL_AD_DECODE_ERROR;
                SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_LENGTH_MISMATCH);
                goto f_err;
                }
        if ((i > 0) && (ssl_bytes_to_cipher_list(s,p,i,&(ciphers))
                == NULL))
                {
                goto err;
                }
        p+=i;

        /* If it is a hit, check that the cipher is in the list */
        if ((s->hit) && (i > 0))
                {
                j=0;
                id=s->session->cipher->id;

#ifdef CIPHER_DEBUG
                printf("client sent %d ciphers\n",sk_num(ciphers));
#endif
                for (i=0; i<sk_SSL_CIPHER_num(ciphers); i++)
                        {
                        c=sk_SSL_CIPHER_value(ciphers,i);
#ifdef CIPHER_DEBUG
                        printf("client [%2d of %2d]:%s\n",
                                i,sk_num(ciphers),SSL_CIPHER_get_name(c));
#endif
                        if (c->id == id)
                                {
                                j=1;
                                break;
                                }
                        }
                if (j == 0 && (s->options & SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG) && (sk_SSL_CIPHER_num(ciphers) == 1))
                        {
                        /* Special case as client bug workaround: the previously used cipher may
                         * not be in the current list, the client instead might be trying to
                         * continue using a cipher that before wasn't chosen due to server
                         * preferences.  We'll have to reject the connection if the cipher is not
                         * enabled, though. */
                        c = sk_SSL_CIPHER_value(ciphers, 0);
                        if (sk_SSL_CIPHER_find(SSL_get_ciphers(s), c) >= 0)
                                {
                                s->session->cipher = c;
                                j = 1;
                                }
                        }
                if (j == 0)
                        {
                        /* we need to have the cipher in the cipher
                         * list if we are asked to reuse it */
                        al=SSL_AD_ILLEGAL_PARAMETER;
                        SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_REQUIRED_CIPHER_MISSING);
                        goto f_err;
                        }
                }

        /* compression */
        i= *(p++);
        if ((p+i) > (d+n))
                {
                /* not enough data */
                al=SSL_AD_DECODE_ERROR;
                SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_LENGTH_MISMATCH);
                goto f_err;
                }
        q=p;
        for (j=0; j<i; j++)
                {
                if (p[j] == 0) break;
                }

        p+=i;
        if (j >= i)
                {
                /* no compress */
                al=SSL_AD_DECODE_ERROR;
                SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_NO_COMPRESSION_SPECIFIED);
                goto f_err;
                }

#ifndef OPENSSL_NO_TLSEXT
        /* TLS extensions*/
        if (s->version >= SSL3_VERSION)
                {
                if (!ssl_parse_clienthello_tlsext(s,&p,d,n, &al))
                        {
                        /* 'al' set by ssl_parse_clienthello_tlsext */
                        SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_PARSE_TLSEXT);
                        goto f_err;
                        }
                }
                if (ssl_check_clienthello_tlsext(s) <= 0) {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_CLIENTHELLO_TLSEXT);
                        goto err;
                }

        /* Check if we want to use external pre-shared secret for this
         * handshake for not reused session only. We need to generate
         * server_random before calling tls_session_secret_cb in order to allow
         * SessionTicket processing to use it in key derivation. */
        {
                unsigned long Time;
                unsigned char *pos;
                Time=(unsigned long)time(NULL);                 /* Time */
                pos=s->s3->server_random;
                l2n(Time,pos);
                if (RAND_pseudo_bytes(pos,SSL3_RANDOM_SIZE-4) <= 0)
                        {
                        al=SSL_AD_INTERNAL_ERROR;
                        goto f_err;
                        }
        }

        if (!s->hit && s->version >= TLS1_VERSION && s->tls_session_secret_cb)
                {
                SSL_CIPHER *pref_cipher=NULL;

                s->session->master_key_length=sizeof(s->session->master_key);
                if(s->tls_session_secret_cb(s, s->session->master_key, &s->session->master_key_length,
                        ciphers, &pref_cipher, s->tls_session_secret_cb_arg))
                        {
                        s->hit=1;
                        s->session->ciphers=ciphers;
                        s->session->verify_result=X509_V_OK;

                        ciphers=NULL;

                        /* check if some cipher was preferred by call back */
                        pref_cipher=pref_cipher ? pref_cipher : ssl3_choose_cipher(s, s->session->ciphers, SSL_get_ciphers(s));
                        if (pref_cipher == NULL)
                                {
                                al=SSL_AD_HANDSHAKE_FAILURE;
                                SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_NO_SHARED_CIPHER);
                                goto f_err;
                                }

                        s->session->cipher=pref_cipher;

                        if (s->cipher_list)
                                sk_SSL_CIPHER_free(s->cipher_list);

                        if (s->cipher_list_by_id)
                                sk_SSL_CIPHER_free(s->cipher_list_by_id);

                        s->cipher_list = sk_SSL_CIPHER_dup(s->session->ciphers);
                        s->cipher_list_by_id = sk_SSL_CIPHER_dup(s->session->ciphers);
                        }
                }
#endif

        /* Worst case, we will use the NULL compression, but if we have other
         * options, we will now look for them.  We have i-1 compression
         * algorithms from the client, starting at q. */
        s->s3->tmp.new_compression=NULL;
#ifndef OPENSSL_NO_COMP
        /* This only happens if we have a cache hit */
        if (s->session->compress_meth != 0)
                {
                int m, comp_id = s->session->compress_meth;
                /* Perform sanity checks on resumed compression algorithm */
                /* Can't disable compression */
                if (s->options & SSL_OP_NO_COMPRESSION)
                        {
                        al=SSL_AD_INTERNAL_ERROR;
                        SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_INCONSISTENT_COMPRESSION);
                        goto f_err;
                        }
                /* Look for resumed compression method */
                for (m = 0; m < sk_SSL_COMP_num(s->ctx->comp_methods); m++)
                        {
                        comp=sk_SSL_COMP_value(s->ctx->comp_methods,m);
                        if (comp_id == comp->id)
                                {
                                s->s3->tmp.new_compression=comp;
                                break;
                                }
                        }
                if (s->s3->tmp.new_compression == NULL)
                        {
                        al=SSL_AD_INTERNAL_ERROR;
                        SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_INVALID_COMPRESSION_ALGORITHM);
                        goto f_err;
                        }
                /* Look for resumed method in compression list */
                for (m = 0; m < i; m++)
                        {
                        if (q[m] == comp_id)
                                break;
                        }
                if (m >= i)
                        {
                        al=SSL_AD_ILLEGAL_PARAMETER;
                        SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_REQUIRED_COMPRESSSION_ALGORITHM_MISSING);
                        goto f_err;
                        }
                }
        else if (s->hit)
                comp = NULL;
        else if (!(s->options & SSL_OP_NO_COMPRESSION) && s->ctx->comp_methods)
                { /* See if we have a match */
                int m,nn,o,v,done=0;

                nn=sk_SSL_COMP_num(s->ctx->comp_methods);
                for (m=0; m<nn; m++)
                        {
                        comp=sk_SSL_COMP_value(s->ctx->comp_methods,m);
                        v=comp->id;
                        for (o=0; o<i; o++)
                                {
                                if (v == q[o])
                                        {
                                        done=1;
                                        break;
                                        }
                                }
                        if (done) break;
                        }
                if (done)
                        s->s3->tmp.new_compression=comp;
                else
                        comp=NULL;
                }
#else
        /* If compression is disabled we'd better not try to resume a session
         * using compression.
         */
        if (s->session->compress_meth != 0)
                {
                al=SSL_AD_INTERNAL_ERROR;
                SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_INCONSISTENT_COMPRESSION);
                goto f_err;
                }
#endif

        /* Given s->session->ciphers and SSL_get_ciphers, we must
         * pick a cipher */

        if (!s->hit)
                {
#ifdef OPENSSL_NO_COMP
                s->session->compress_meth=0;
#else
                s->session->compress_meth=(comp == NULL)?0:comp->id;
#endif
                if (s->session->ciphers != NULL)
                        sk_SSL_CIPHER_free(s->session->ciphers);
                s->session->ciphers=ciphers;
                if (ciphers == NULL)
                        {
                        al=SSL_AD_ILLEGAL_PARAMETER;
                        SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_NO_CIPHERS_PASSED);
                        goto f_err;
                        }
                ciphers=NULL;
                c=ssl3_choose_cipher(s,s->session->ciphers,
                                     SSL_get_ciphers(s));

                if (c == NULL)
                        {
                        al=SSL_AD_HANDSHAKE_FAILURE;
                        SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_NO_SHARED_CIPHER);
                        goto f_err;
                        }
                s->s3->tmp.new_cipher=c;
                /* check whether we should disable session resumption */
                if (s->not_resumable_session_cb != NULL)
                        s->session->not_resumable=s->not_resumable_session_cb(s,
                                ((c->algorithm_mkey & (SSL_kEDH | SSL_kEECDH)) != 0));
                if (s->session->not_resumable)
                        /* do not send a session ticket */
                        s->tlsext_ticket_expected = 0;
                }
        else
                {
                /* Session-id reuse */
#ifdef REUSE_CIPHER_BUG
                STACK_OF(SSL_CIPHER) *sk;
                SSL_CIPHER *nc=NULL;
                SSL_CIPHER *ec=NULL;

                if (s->options & SSL_OP_NETSCAPE_DEMO_CIPHER_CHANGE_BUG)
                        {
                        sk=s->session->ciphers;
                        for (i=0; i<sk_SSL_CIPHER_num(sk); i++)
                                {
                                c=sk_SSL_CIPHER_value(sk,i);
                                if (c->algorithm_enc & SSL_eNULL)
                                        nc=c;
                                if (SSL_C_IS_EXPORT(c))
                                        ec=c;
                                }
                        if (nc != NULL)
                                s->s3->tmp.new_cipher=nc;
                        else if (ec != NULL)
                                s->s3->tmp.new_cipher=ec;
                        else
                                s->s3->tmp.new_cipher=s->session->cipher;
                        }
                else
#endif
                s->s3->tmp.new_cipher=s->session->cipher;
                }

        if (!ssl3_digest_cached_records(s))
                goto f_err;
        
        /* we now have the following setup. 
         * client_random
         * cipher_list          - our prefered list of ciphers
         * ciphers              - the clients prefered list of ciphers
         * compression          - basically ignored right now
         * ssl version is set   - sslv3
         * s->session           - The ssl session has been setup.
         * s->hit               - session reuse flag
         * s->tmp.new_cipher    - the new cipher to use.
         */

        if (ret < 0) ret=1;
        if (0)
                {
f_err:
                ssl3_send_alert(s,SSL3_AL_FATAL,al);
                }
err:
        if (ciphers != NULL) sk_SSL_CIPHER_free(ciphers);
        return(ret);
        }

int ssl3_send_server_hello(SSL *s)
        {
        unsigned char *buf;
        unsigned char *p,*d;
        int i,sl;
        unsigned long l;
#ifdef OPENSSL_NO_TLSEXT
        unsigned long Time;
#endif

        if (s->state == SSL3_ST_SW_SRVR_HELLO_A)
                {
                buf=(unsigned char *)s->init_buf->data;
#ifdef OPENSSL_NO_TLSEXT
                p=s->s3->server_random;
                /* Generate server_random if it was not needed previously */
                Time=(unsigned long)time(NULL);                 /* Time */
                l2n(Time,p);
                if (RAND_pseudo_bytes(p,SSL3_RANDOM_SIZE-4) <= 0)
                        return -1;
#endif
                /* Do the message type and length last */
                d=p= &(buf[4]);

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

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

                /* now in theory we have 3 options to sending back the
                 * session id.  If it is a re-use, we send back the
                 * old session-id, if it is a new session, we send
                 * back the new session-id or we send back a 0 length
                 * session-id if we want it to be single use.
                 * Currently I will not implement the '0' length session-id
                 * 12-Jan-98 - I'll now support the '0' length stuff.
                 *
                 * We also have an additional case where stateless session
                 * resumption is successful: we always send back the old
                 * session id. In this case s->hit is non zero: this can
                 * only happen if stateless session resumption is succesful
                 * if session caching is disabled so existing functionality
                 * is unaffected.
                 */
                if (s->session->not_resumable ||
                        (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER)
                                && !s->hit))
                        s->session->session_id_length=0;

                sl=s->session->session_id_length;
                if (sl > (int)sizeof(s->session->session_id))
                        {
                        SSLerr(SSL_F_SSL3_SEND_SERVER_HELLO, ERR_R_INTERNAL_ERROR);
                        return -1;
                        }
                *(p++)=sl;
                memcpy(p,s->session->session_id,sl);
                p+=sl;

                /* put the cipher */
                i=ssl3_put_cipher_by_char(s->s3->tmp.new_cipher,p);
                p+=i;

                /* put the compression method */
#ifdef OPENSSL_NO_COMP
                        *(p++)=0;
#else
                if (s->s3->tmp.new_compression == NULL)
                        *(p++)=0;
                else
                        *(p++)=s->s3->tmp.new_compression->id;
#endif
#ifndef OPENSSL_NO_TLSEXT
                if (ssl_prepare_serverhello_tlsext(s) <= 0)
                        {
                        SSLerr(SSL_F_SSL3_SEND_SERVER_HELLO,SSL_R_SERVERHELLO_TLSEXT);
                        return -1;
                        }
                if ((p = ssl_add_serverhello_tlsext(s, p, buf+SSL3_RT_MAX_PLAIN_LENGTH)) == NULL)
                        {
                        SSLerr(SSL_F_SSL3_SEND_SERVER_HELLO,ERR_R_INTERNAL_ERROR);
                        return -1;
                        }
#endif
                /* do the header */
                l=(p-d);
                d=buf;
                *(d++)=SSL3_MT_SERVER_HELLO;
                l2n3(l,d);

                s->state=SSL3_ST_SW_SRVR_HELLO_B;
                /* number of bytes to write */
                s->init_num=p-buf;
                s->init_off=0;
                }

        /* SSL3_ST_SW_SRVR_HELLO_B */
        return(ssl3_do_write(s,SSL3_RT_HANDSHAKE));
        }

int ssl3_send_server_done(SSL *s)
        {
        unsigned char *p;

        if (s->state == SSL3_ST_SW_SRVR_DONE_A)
                {
                p=(unsigned char *)s->init_buf->data;

                /* do the header */
                *(p++)=SSL3_MT_SERVER_DONE;
                *(p++)=0;
                *(p++)=0;
                *(p++)=0;

                s->state=SSL3_ST_SW_SRVR_DONE_B;
                /* number of bytes to write */
                s->init_num=4;
                s->init_off=0;
                }

        /* SSL3_ST_SW_SRVR_DONE_B */
        return(ssl3_do_write(s,SSL3_RT_HANDSHAKE));
        }

int ssl3_send_server_key_exchange(SSL *s)
        {
#ifndef OPENSSL_NO_RSA
        unsigned char *q;
        int j,num;
        RSA *rsa;
        unsigned char md_buf[MD5_DIGEST_LENGTH+SHA_DIGEST_LENGTH];
        unsigned int u;
#endif
#ifndef OPENSSL_NO_DH
        DH *dh=NULL,*dhp;
#endif
#ifndef OPENSSL_NO_ECDH
        EC_KEY *ecdh=NULL, *ecdhp;
        unsigned char *encodedPoint = NULL;
        int encodedlen = 0;
        int curve_id = 0;
        BN_CTX *bn_ctx = NULL; 
#endif
        EVP_PKEY *pkey;
        unsigned char *p,*d;
        int al,i;
        unsigned long type;
        int n;
        CERT *cert;
        BIGNUM *r[4];
        int nr[4],kn;
        BUF_MEM *buf;
        EVP_MD_CTX md_ctx;

        EVP_MD_CTX_init(&md_ctx);
        if (s->state == SSL3_ST_SW_KEY_EXCH_A)
                {
                type=s->s3->tmp.new_cipher->algorithm_mkey;
                cert=s->cert;

                buf=s->init_buf;

                r[0]=r[1]=r[2]=r[3]=NULL;
                n=0;
#ifndef OPENSSL_NO_RSA
                if (type & SSL_kRSA)
                        {
                        rsa=cert->rsa_tmp;
                        if ((rsa == NULL) && (s->cert->rsa_tmp_cb != NULL))
                                {
                                rsa=s->cert->rsa_tmp_cb(s,
                                      SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
                                      SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
                                if(rsa == NULL)
                                {
                                        al=SSL_AD_HANDSHAKE_FAILURE;
                                        SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_ERROR_GENERATING_TMP_RSA_KEY);
                                        goto f_err;
                                }
                                RSA_up_ref(rsa);
                                cert->rsa_tmp=rsa;
                                }
                        if (rsa == NULL)
                                {
                                al=SSL_AD_HANDSHAKE_FAILURE;
                                SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_RSA_KEY);
                                goto f_err;
                                }
                        r[0]=rsa->n;
                        r[1]=rsa->e;
                        s->s3->tmp.use_rsa_tmp=1;
                        }
                else
#endif
#ifndef OPENSSL_NO_DH
                        if (type & SSL_kEDH)
                        {
                        dhp=cert->dh_tmp;
                        if ((dhp == NULL) && (s->cert->dh_tmp_cb != NULL))
                                dhp=s->cert->dh_tmp_cb(s,
                                      SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
                                      SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
                        if (dhp == NULL)
                                {
                                al=SSL_AD_HANDSHAKE_FAILURE;
                                SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_DH_KEY);
                                goto f_err;
                                }

                        if (s->s3->tmp.dh != NULL)
                                {
                                DH_free(dh);
                                SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);
                                goto err;
                                }

                        if ((dh=DHparams_dup(dhp)) == NULL)
                                {
                                SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_DH_LIB);
                                goto err;
                                }

                        s->s3->tmp.dh=dh;
                        if ((dhp->pub_key == NULL ||
                             dhp->priv_key == NULL ||
                             (s->options & SSL_OP_SINGLE_DH_USE)))
                                {
                                if(!DH_generate_key(dh))
                                    {
                                    SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,
                                           ERR_R_DH_LIB);
                                    goto err;
                                    }
                                }
                        else
                                {
                                dh->pub_key=BN_dup(dhp->pub_key);
                                dh->priv_key=BN_dup(dhp->priv_key);
                                if ((dh->pub_key == NULL) ||
                                        (dh->priv_key == NULL))
                                        {
                                        SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_DH_LIB);
                                        goto err;
                                        }
                                }
                        r[0]=dh->p;
                        r[1]=dh->g;
                        r[2]=dh->pub_key;
                        }
                else 
#endif
#ifndef OPENSSL_NO_ECDH
                        if (type & SSL_kEECDH)
                        {
                        const EC_GROUP *group;

                        ecdhp=cert->ecdh_tmp;
                        if ((ecdhp == NULL) && (s->cert->ecdh_tmp_cb != NULL))
                                {
                                ecdhp=s->cert->ecdh_tmp_cb(s,
                                      SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
                                      SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
                                }
                        if (ecdhp == NULL)
                                {
                                al=SSL_AD_HANDSHAKE_FAILURE;
                                SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_ECDH_KEY);
                                goto f_err;
                                }

                        if (s->s3->tmp.ecdh != NULL)
                                {
                                EC_KEY_free(s->s3->tmp.ecdh); 
                                SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);
                                goto err;
                                }

                        /* Duplicate the ECDH structure. */
                        if (ecdhp == NULL)
                                {
                                SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_ECDH_LIB);
                                goto err;
                                }
                        if (!EC_KEY_up_ref(ecdhp))
                                {
                                SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_ECDH_LIB);
                                goto err;
                                }
                        ecdh = ecdhp;

                        s->s3->tmp.ecdh=ecdh;
                        if ((EC_KEY_get0_public_key(ecdh) == NULL) ||
                            (EC_KEY_get0_private_key(ecdh) == NULL) ||
                            (s->options & SSL_OP_SINGLE_ECDH_USE))
                                {
                                if(!EC_KEY_generate_key(ecdh))
                                    {
                                    SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_ECDH_LIB);
                                    goto err;
                                    }
                                }

                        if (((group = EC_KEY_get0_group(ecdh)) == NULL) ||
                            (EC_KEY_get0_public_key(ecdh)  == NULL) ||
                            (EC_KEY_get0_private_key(ecdh) == NULL))
                                {
                                SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_ECDH_LIB);
                                goto err;
                                }

                        if (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher) &&
                            (EC_GROUP_get_degree(group) > 163)) 
                                {
                                SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_ECGROUP_TOO_LARGE_FOR_CIPHER);
                                goto err;
                                }

                        /* XXX: For now, we only support ephemeral ECDH
                         * keys over named (not generic) curves. For 
                         * supported named curves, curve_id is non-zero.
                         */
                        if ((curve_id = 
                            tls1_ec_nid2curve_id(EC_GROUP_get_curve_name(group)))
                            == 0)
                                {
                                SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNSUPPORTED_ELLIPTIC_CURVE);
                                goto err;
                                }

                        /* Encode the public key.
                         * First check the size of encoding and
                         * allocate memory accordingly.
                         */
                        encodedlen = EC_POINT_point2oct(group, 
                            EC_KEY_get0_public_key(ecdh),
                            POINT_CONVERSION_UNCOMPRESSED, 
                            NULL, 0, NULL);

                        encodedPoint = (unsigned char *) 
                            OPENSSL_malloc(encodedlen*sizeof(unsigned char)); 
                        bn_ctx = BN_CTX_new();
                        if ((encodedPoint == NULL) || (bn_ctx == NULL))
                                {
                                SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_MALLOC_FAILURE);
                                goto err;
                                }


                        encodedlen = EC_POINT_point2oct(group, 
                            EC_KEY_get0_public_key(ecdh), 
                            POINT_CONVERSION_UNCOMPRESSED, 
                            encodedPoint, encodedlen, bn_ctx);

                        if (encodedlen == 0) 
                                {
                                SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_ECDH_LIB);
                                goto err;
                                }

                        BN_CTX_free(bn_ctx);  bn_ctx=NULL;

                        /* XXX: For now, we only support named (not 
                         * generic) curves in ECDH ephemeral key exchanges.
                         * In this situation, we need four additional bytes
                         * to encode the entire ServerECDHParams
                         * structure. 
                         */
                        n = 4 + encodedlen;

                        /* We'll generate the serverKeyExchange message
                         * explicitly so we can set these to NULLs
                         */
                        r[0]=NULL;
                        r[1]=NULL;
                        r[2]=NULL;
                        r[3]=NULL;
                        }
                else 
#endif /* !OPENSSL_NO_ECDH */
#ifndef OPENSSL_NO_PSK
                        if (type & SSL_kPSK)
                                {
                                /* reserve size for record length and PSK identity hint*/
                                n+=2+strlen(s->ctx->psk_identity_hint);
                                }
                        else
#endif /* !OPENSSL_NO_PSK */
                        {
                        al=SSL_AD_HANDSHAKE_FAILURE;
                        SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE);
                        goto f_err;
                        }
                for (i=0; r[i] != NULL; i++)
                        {
                        nr[i]=BN_num_bytes(r[i]);
                        n+=2+nr[i];
                        }

                if (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL)
                        && !(s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK))
                        {
                        if ((pkey=ssl_get_sign_pkey(s,s->s3->tmp.new_cipher))
                                == NULL)
                                {
                                al=SSL_AD_DECODE_ERROR;
                                goto f_err;
                                }
                        kn=EVP_PKEY_size(pkey);
                        }
                else
                        {
                        pkey=NULL;
                        kn=0;
                        }

                if (!BUF_MEM_grow_clean(buf,n+4+kn))
                        {
                        SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_BUF);
                        goto err;
                        }
                d=(unsigned char *)s->init_buf->data;
                p= &(d[4]);

                for (i=0; r[i] != NULL; i++)
                        {
                        s2n(nr[i],p);
                        BN_bn2bin(r[i],p);
                        p+=nr[i];
                        }

#ifndef OPENSSL_NO_ECDH
                if (type & SSL_kEECDH) 
                        {
                        /* XXX: For now, we only support named (not generic) curves.
                         * In this situation, the serverKeyExchange message has:
                         * [1 byte CurveType], [2 byte CurveName]
                         * [1 byte length of encoded point], followed by
                         * the actual encoded point itself
                         */
                        *p = NAMED_CURVE_TYPE;
                        p += 1;
                        *p = 0;
                        p += 1;
                        *p = curve_id;
                        p += 1;
                        *p = encodedlen;
                        p += 1;
                        memcpy((unsigned char*)p, 
                            (unsigned char *)encodedPoint, 
                            encodedlen);
                        OPENSSL_free(encodedPoint);
                        p += encodedlen;
                        }
#endif

#ifndef OPENSSL_NO_PSK
                if (type & SSL_kPSK)
                        {
                        /* copy PSK identity hint */
                        s2n(strlen(s->ctx->psk_identity_hint), p); 
                        strncpy((char *)p, s->ctx->psk_identity_hint, strlen(s->ctx->psk_identity_hint));
                        p+=strlen(s->ctx->psk_identity_hint);
                        }
#endif

                /* not anonymous */
                if (pkey != NULL)
                        {
                        /* n is the length of the params, they start at &(d[4])
                         * and p points to the space at the end. */
#ifndef OPENSSL_NO_RSA
                        if (pkey->type == EVP_PKEY_RSA)
                                {
                                q=md_buf;
                                j=0;
                                for (num=2; num > 0; num--)
                                        {
                                        EVP_DigestInit_ex(&md_ctx,(num == 2)
                                                ?s->ctx->md5:s->ctx->sha1, NULL);
                                        EVP_DigestUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
                                        EVP_DigestUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
                                        EVP_DigestUpdate(&md_ctx,&(d[4]),n);
                                        EVP_DigestFinal_ex(&md_ctx,q,
                                                (unsigned int *)&i);
                                        q+=i;
                                        j+=i;
                                        }
                                if (RSA_sign(NID_md5_sha1, md_buf, j,
                                        &(p[2]), &u, pkey->pkey.rsa) <= 0)
                                        {
                                        SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_RSA);
                                        goto err;
                                        }
                                s2n(u,p);
                                n+=u+2;
                                }
                        else
#endif
#if !defined(OPENSSL_NO_DSA)
                                if (pkey->type == EVP_PKEY_DSA)
                                {
                                /* lets do DSS */
                                EVP_SignInit_ex(&md_ctx,EVP_dss1(), NULL);
                                EVP_SignUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
                                EVP_SignUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
                                EVP_SignUpdate(&md_ctx,&(d[4]),n);
                                if (!EVP_SignFinal(&md_ctx,&(p[2]),
                                        (unsigned int *)&i,pkey))
                                        {
                                        SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_DSA);
                                        goto err;
                                        }
                                s2n(i,p);
                                n+=i+2;
                                }
                        else
#endif
#if !defined(OPENSSL_NO_ECDSA)
                                if (pkey->type == EVP_PKEY_EC)
                                {
                                /* let's do ECDSA */
                                EVP_SignInit_ex(&md_ctx,EVP_ecdsa(), NULL);
                                EVP_SignUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
                                EVP_SignUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
                                EVP_SignUpdate(&md_ctx,&(d[4]),n);
                                if (!EVP_SignFinal(&md_ctx,&(p[2]),
                                        (unsigned int *)&i,pkey))
                                        {
                                        SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_ECDSA);
                                        goto err;
                                        }
                                s2n(i,p);
                                n+=i+2;
                                }
                        else
#endif
                                {
                                /* Is this error check actually needed? */
                                al=SSL_AD_HANDSHAKE_FAILURE;
                                SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_PKEY_TYPE);
                                goto f_err;
                                }
                        }

                *(d++)=SSL3_MT_SERVER_KEY_EXCHANGE;
                l2n3(n,d);

                /* we should now have things packed up, so lets send
                 * it off */
                s->init_num=n+4;
                s->init_off=0;
                }

        s->state = SSL3_ST_SW_KEY_EXCH_B;
        EVP_MD_CTX_cleanup(&md_ctx);
        return(ssl3_do_write(s,SSL3_RT_HANDSHAKE));
f_err:
        ssl3_send_alert(s,SSL3_AL_FATAL,al);
err:
#ifndef OPENSSL_NO_ECDH
        if (encodedPoint != NULL) OPENSSL_free(encodedPoint);
        BN_CTX_free(bn_ctx);
#endif
        EVP_MD_CTX_cleanup(&md_ctx);
        return(-1);
        }

int ssl3_send_certificate_request(SSL *s)
        {
        unsigned char *p,*d;
        int i,j,nl,off,n;
        STACK_OF(X509_NAME) *sk=NULL;
        X509_NAME *name;
        BUF_MEM *buf;

        if (s->state == SSL3_ST_SW_CERT_REQ_A)
                {
                buf=s->init_buf;

                d=p=(unsigned char *)&(buf->data[4]);

                /* get the list of acceptable cert types */
                p++;
                n=ssl3_get_req_cert_type(s,p);
                d[0]=n;
                p+=n;
                n++;

                off=n;
                p+=2;
                n+=2;

                sk=SSL_get_client_CA_list(s);
                nl=0;
                if (sk != NULL)
                        {
                        for (i=0; i<sk_X509_NAME_num(sk); i++)
                                {
                                name=sk_X509_NAME_value(sk,i);
                                j=i2d_X509_NAME(name,NULL);
                                if (!BUF_MEM_grow_clean(buf,4+n+j+2))
                                        {
                                        SSLerr(SSL_F_SSL3_SEND_CERTIFICATE_REQUEST,ERR_R_BUF_LIB);
                                        goto err;
                                        }
                                p=(unsigned char *)&(buf->data[4+n]);
                                if (!(s->options & SSL_OP_NETSCAPE_CA_DN_BUG))
                                        {
                                        s2n(j,p);
                                        i2d_X509_NAME(name,&p);
                                        n+=2+j;
                                        nl+=2+j;
                                        }
                                else
                                        {
                                        d=p;
                                        i2d_X509_NAME(name,&p);
                                        j-=2; s2n(j,d); j+=2;
                                        n+=j;
                                        nl+=j;
                                        }
                                }
                        }
                /* else no CA names */
                p=(unsigned char *)&(buf->data[4+off]);
                s2n(nl,p);

                d=(unsigned char *)buf->data;
                *(d++)=SSL3_MT_CERTIFICATE_REQUEST;
                l2n3(n,d);

                /* we should now have things packed up, so lets send
                 * it off */

                s->init_num=n+4;
                s->init_off=0;
#ifdef NETSCAPE_HANG_BUG
                p=(unsigned char *)s->init_buf->data + s->init_num;

                /* do the header */
                *(p++)=SSL3_MT_SERVER_DONE;
                *(p++)=0;
                *(p++)=0;
                *(p++)=0;
                s->init_num += 4;
#endif

                s->state = SSL3_ST_SW_CERT_REQ_B;
                }

        /* SSL3_ST_SW_CERT_REQ_B */
        return(ssl3_do_write(s,SSL3_RT_HANDSHAKE));
err:
        return(-1);
        }

int ssl3_get_client_key_exchange(SSL *s)
        {
        int i,al,ok;
        long n;
        unsigned long alg_k;
        unsigned char *p;
#ifndef OPENSSL_NO_RSA
        RSA *rsa=NULL;
        EVP_PKEY *pkey=NULL;
#endif
#ifndef OPENSSL_NO_DH
        BIGNUM *pub=NULL;
        DH *dh_srvr;
#endif
#ifndef OPENSSL_NO_KRB5
        KSSL_ERR kssl_err;
#endif /* OPENSSL_NO_KRB5 */

#ifndef OPENSSL_NO_ECDH
        EC_KEY *srvr_ecdh = NULL;
        EVP_PKEY *clnt_pub_pkey = NULL;
        EC_POINT *clnt_ecpoint = NULL;
        BN_CTX *bn_ctx = NULL; 
#endif

        n=s->method->ssl_get_message(s,
                SSL3_ST_SR_KEY_EXCH_A,
                SSL3_ST_SR_KEY_EXCH_B,
                SSL3_MT_CLIENT_KEY_EXCHANGE,
                2048, /* ??? */
                &ok);

        if (!ok) return((int)n);
        p=(unsigned char *)s->init_msg;

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

#ifndef OPENSSL_NO_RSA
        if (alg_k & SSL_kRSA)
                {
                /* FIX THIS UP EAY EAY EAY EAY */
                if (s->s3->tmp.use_rsa_tmp)
                        {
                        if ((s->cert != NULL) && (s->cert->rsa_tmp != NULL))
                                rsa=s->cert->rsa_tmp;
                        /* Don't do a callback because rsa_tmp should
                         * be sent already */
                        if (rsa == NULL)
                                {
                                al=SSL_AD_HANDSHAKE_FAILURE;
                                SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_MISSING_TMP_RSA_PKEY);
                                goto f_err;

                                }
                        }
                else
                        {
                        pkey=s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey;
                        if (    (pkey == NULL) ||
                                (pkey->type != EVP_PKEY_RSA) ||
                                (pkey->pkey.rsa == NULL))
                                {
                                al=SSL_AD_HANDSHAKE_FAILURE;
                                SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_MISSING_RSA_CERTIFICATE);
                                goto f_err;
                                }
                        rsa=pkey->pkey.rsa;
                        }

                /* TLS and [incidentally] DTLS{0xFEFF} */
                if (s->version > SSL3_VERSION && s->version != DTLS1_BAD_VER)
                        {
                        n2s(p,i);
                        if (n != i+2)
                                {
                                if (!(s->options & SSL_OP_TLS_D5_BUG))
                                        {
                                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_TLS_RSA_ENCRYPTED_VALUE_LENGTH_IS_WRONG);
                                        goto err;
                                        }
                                else
                                        p-=2;
                                }
                        else
                                n=i;
                        }

                i=RSA_private_decrypt((int)n,p,p,rsa,RSA_PKCS1_PADDING);

                al = -1;
                
                if (i != SSL_MAX_MASTER_KEY_LENGTH)
                        {
                        al=SSL_AD_DECODE_ERROR;
                        /* SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_BAD_RSA_DECRYPT); */
                        }

                if ((al == -1) && !((p[0] == (s->client_version>>8)) && (p[1] == (s->client_version & 0xff))))
                        {
                        /* The premaster secret must contain the same version number as the
                         * ClientHello to detect version rollback attacks (strangely, the
                         * protocol does not offer such protection for DH ciphersuites).
                         * However, buggy clients exist that send the negotiated protocol
                         * version instead if the server does not support the requested
                         * protocol version.
                         * If SSL_OP_TLS_ROLLBACK_BUG is set, tolerate such clients. */
                        if (!((s->options & SSL_OP_TLS_ROLLBACK_BUG) &&
                                (p[0] == (s->version>>8)) && (p[1] == (s->version & 0xff))))
                                {
                                al=SSL_AD_DECODE_ERROR;
                                /* SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_BAD_PROTOCOL_VERSION_NUMBER); */

                                /* The Klima-Pokorny-Rosa extension of Bleichenbacher's attack
                                 * (http://eprint.iacr.org/2003/052/) exploits the version
                                 * number check as a "bad version oracle" -- an alert would
                                 * reveal that the plaintext corresponding to some ciphertext
                                 * made up by the adversary is properly formatted except
                                 * that the version number is wrong.  To avoid such attacks,
                                 * we should treat this just like any other decryption error. */
                                }
                        }

                if (al != -1)
                        {
                        /* Some decryption failure -- use random value instead as countermeasure
                         * against Bleichenbacher's attack on PKCS #1 v1.5 RSA padding
                         * (see RFC 2246, section 7.4.7.1). */
                        ERR_clear_error();
                        i = SSL_MAX_MASTER_KEY_LENGTH;
                        p[0] = s->client_version >> 8;
                        p[1] = s->client_version & 0xff;
                        if (RAND_pseudo_bytes(p+2, i-2) <= 0) /* should be RAND_bytes, but we cannot work around a failure */
                                goto err;
                        }
        
                s->session->master_key_length=
                        s->method->ssl3_enc->generate_master_secret(s,
                                s->session->master_key,
                                p,i);
                OPENSSL_cleanse(p,i);
                }
        else
#endif
#ifndef OPENSSL_NO_DH
                if (alg_k & (SSL_kEDH|SSL_kDHr|SSL_kDHd))
                {
                n2s(p,i);
                if (n != i+2)
                        {
                        if (!(s->options & SSL_OP_SSLEAY_080_CLIENT_DH_BUG))
                                {
                                SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_DH_PUBLIC_VALUE_LENGTH_IS_WRONG);
                                goto err;
                                }
                        else
                                {
                                p-=2;
                                i=(int)n;
                                }
                        }

                if (n == 0L) /* the parameters are in the cert */
                        {
                        al=SSL_AD_HANDSHAKE_FAILURE;
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_UNABLE_TO_DECODE_DH_CERTS);
                        goto f_err;
                        }
                else
                        {
                        if (s->s3->tmp.dh == NULL)
                                {
                                al=SSL_AD_HANDSHAKE_FAILURE;
                                SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_MISSING_TMP_DH_KEY);
                                goto f_err;
                                }
                        else
                                dh_srvr=s->s3->tmp.dh;
                        }

                pub=BN_bin2bn(p,i,NULL);
                if (pub == NULL)
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_BN_LIB);
                        goto err;
                        }

                i=DH_compute_key(p,pub,dh_srvr);

                if (i <= 0)
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,ERR_R_DH_LIB);
                        goto err;
                        }

                DH_free(s->s3->tmp.dh);
                s->s3->tmp.dh=NULL;

                BN_clear_free(pub);
                pub=NULL;
                s->session->master_key_length=
                        s->method->ssl3_enc->generate_master_secret(s,
                                s->session->master_key,p,i);
                OPENSSL_cleanse(p,i);
                }
        else
#endif
#ifndef OPENSSL_NO_KRB5
        if (alg_k & SSL_kKRB5)
                {
                krb5_error_code         krb5rc;
                krb5_data               enc_ticket;
                krb5_data               authenticator;
                krb5_data               enc_pms;
                KSSL_CTX                *kssl_ctx = s->kssl_ctx;
                EVP_CIPHER_CTX          ciph_ctx;
                const EVP_CIPHER        *enc = NULL;
                unsigned char           iv[EVP_MAX_IV_LENGTH];
                unsigned char           pms[SSL_MAX_MASTER_KEY_LENGTH
                                               + EVP_MAX_BLOCK_LENGTH];
                int                  padl, outl;
                krb5_timestamp          authtime = 0;
                krb5_ticket_times       ttimes;

                EVP_CIPHER_CTX_init(&ciph_ctx);

                if (!kssl_ctx)  kssl_ctx = kssl_ctx_new();

                n2s(p,i);
                enc_ticket.length = i;

                if (n < (long)(enc_ticket.length + 6))
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                SSL_R_DATA_LENGTH_TOO_LONG);
                        goto err;
                        }

                enc_ticket.data = (char *)p;
                p+=enc_ticket.length;

                n2s(p,i);
                authenticator.length = i;

                if (n < (long)(enc_ticket.length + authenticator.length + 6))
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                SSL_R_DATA_LENGTH_TOO_LONG);
                        goto err;
                        }

                authenticator.data = (char *)p;
                p+=authenticator.length;

                n2s(p,i);
                enc_pms.length = i;
                enc_pms.data = (char *)p;
                p+=enc_pms.length;

                /* Note that the length is checked again below,
                ** after decryption
                */
                if(enc_pms.length > sizeof pms)
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                               SSL_R_DATA_LENGTH_TOO_LONG);
                        goto err;
                        }

                if (n != (long)(enc_ticket.length + authenticator.length +
                                                enc_pms.length + 6))
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                SSL_R_DATA_LENGTH_TOO_LONG);
                        goto err;
                        }

                if ((krb5rc = kssl_sget_tkt(kssl_ctx, &enc_ticket, &ttimes,
                                        &kssl_err)) != 0)
                        {
#ifdef KSSL_DEBUG
                        printf("kssl_sget_tkt rtn %d [%d]\n",
                                krb5rc, kssl_err.reason);
                        if (kssl_err.text)
                                printf("kssl_err text= %s\n", kssl_err.text);
#endif  /* KSSL_DEBUG */
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                kssl_err.reason);
                        goto err;
                        }

                /*  Note: no authenticator is not considered an error,
                **  but will return authtime == 0.
                */
                if ((krb5rc = kssl_check_authent(kssl_ctx, &authenticator,
                                        &authtime, &kssl_err)) != 0)
                        {
#ifdef KSSL_DEBUG
                        printf("kssl_check_authent rtn %d [%d]\n",
                                krb5rc, kssl_err.reason);
                        if (kssl_err.text)
                                printf("kssl_err text= %s\n", kssl_err.text);
#endif  /* KSSL_DEBUG */
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                kssl_err.reason);
                        goto err;
                        }

                if ((krb5rc = kssl_validate_times(authtime, &ttimes)) != 0)
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE, krb5rc);
                        goto err;
                        }

#ifdef KSSL_DEBUG
                kssl_ctx_show(kssl_ctx);
#endif  /* KSSL_DEBUG */

                enc = kssl_map_enc(kssl_ctx->enctype);
                if (enc == NULL)
                    goto err;

                memset(iv, 0, sizeof iv);       /* per RFC 1510 */

                if (!EVP_DecryptInit_ex(&ciph_ctx,enc,NULL,kssl_ctx->key,iv))
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                SSL_R_DECRYPTION_FAILED);
                        goto err;
                        }
                if (!EVP_DecryptUpdate(&ciph_ctx, pms,&outl,
                                        (unsigned char *)enc_pms.data, enc_pms.length))
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                SSL_R_DECRYPTION_FAILED);
                        goto err;
                        }
                if (outl > SSL_MAX_MASTER_KEY_LENGTH)
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                SSL_R_DATA_LENGTH_TOO_LONG);
                        goto err;
                        }
                if (!EVP_DecryptFinal_ex(&ciph_ctx,&(pms[outl]),&padl))
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                SSL_R_DECRYPTION_FAILED);
                        goto err;
                        }
                outl += padl;
                if (outl > SSL_MAX_MASTER_KEY_LENGTH)
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                SSL_R_DATA_LENGTH_TOO_LONG);
                        goto err;
                        }
                if (!((pms[0] == (s->client_version>>8)) && (pms[1] == (s->client_version & 0xff))))
                    {
                    /* The premaster secret must contain the same version number as the
                     * ClientHello to detect version rollback attacks (strangely, the
                     * protocol does not offer such protection for DH ciphersuites).
                     * However, buggy clients exist that send random bytes instead of
                     * the protocol version.
                     * If SSL_OP_TLS_ROLLBACK_BUG is set, tolerate such clients. 
                     * (Perhaps we should have a separate BUG value for the Kerberos cipher)
                     */
                    if (!(s->options & SSL_OP_TLS_ROLLBACK_BUG))
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                               SSL_AD_DECODE_ERROR);
                        goto err;
                        }
                    }

                EVP_CIPHER_CTX_cleanup(&ciph_ctx);

                s->session->master_key_length=
                        s->method->ssl3_enc->generate_master_secret(s,
                                s->session->master_key, pms, outl);

                if (kssl_ctx->client_princ)
                        {
                        size_t len = strlen(kssl_ctx->client_princ);
                        if ( len < SSL_MAX_KRB5_PRINCIPAL_LENGTH ) 
                                {
                                s->session->krb5_client_princ_len = len;
                                memcpy(s->session->krb5_client_princ,kssl_ctx->client_princ,len);
                                }
                        }


                /*  Was doing kssl_ctx_free() here,
                **  but it caused problems for apache.
                **  kssl_ctx = kssl_ctx_free(kssl_ctx);
                **  if (s->kssl_ctx)  s->kssl_ctx = NULL;
                */
                }
        else
#endif  /* OPENSSL_NO_KRB5 */

#ifndef OPENSSL_NO_ECDH
                if (alg_k & (SSL_kEECDH|SSL_kECDHr|SSL_kECDHe))
                {
                int ret = 1;
                int field_size = 0;
                const EC_KEY   *tkey;
                const EC_GROUP *group;
                const BIGNUM *priv_key;

                /* initialize structures for server's ECDH key pair */
                if ((srvr_ecdh = EC_KEY_new()) == NULL) 
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                            ERR_R_MALLOC_FAILURE);
                        goto err;
                        }

                /* Let's get server private key and group information */
                if (alg_k & (SSL_kECDHr|SSL_kECDHe))
                        { 
                        /* use the certificate */
                        tkey = s->cert->pkeys[SSL_PKEY_ECC].privatekey->pkey.ec;
                        }
                else
                        {
                        /* use the ephermeral values we saved when
                         * generating the ServerKeyExchange msg.
                         */
                        tkey = s->s3->tmp.ecdh;
                        }

                group    = EC_KEY_get0_group(tkey);
                priv_key = EC_KEY_get0_private_key(tkey);

                if (!EC_KEY_set_group(srvr_ecdh, group) ||
                    !EC_KEY_set_private_key(srvr_ecdh, priv_key))
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                               ERR_R_EC_LIB);
                        goto err;
                        }

                /* Let's get client's public key */
                if ((clnt_ecpoint = EC_POINT_new(group)) == NULL)
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                            ERR_R_MALLOC_FAILURE);
                        goto err;
                        }

                if (n == 0L) 
                        {
                        /* Client Publickey was in Client Certificate */

                         if (alg_k & SSL_kEECDH)
                                 {
                                 al=SSL_AD_HANDSHAKE_FAILURE;
                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_MISSING_TMP_ECDH_KEY);
                                 goto f_err;
                                 }
                        if (((clnt_pub_pkey=X509_get_pubkey(s->session->peer))
                            == NULL) || 
                            (clnt_pub_pkey->type != EVP_PKEY_EC))
                                {
                                /* XXX: For now, we do not support client
                                 * authentication using ECDH certificates
                                 * so this branch (n == 0L) of the code is
                                 * never executed. When that support is
                                 * added, we ought to ensure the key 
                                 * received in the certificate is 
                                 * authorized for key agreement.
                                 * ECDH_compute_key implicitly checks that
                                 * the two ECDH shares are for the same
                                 * group.
                                 */
                                al=SSL_AD_HANDSHAKE_FAILURE;
                                SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                    SSL_R_UNABLE_TO_DECODE_ECDH_CERTS);
                                goto f_err;
                                }

                        if (EC_POINT_copy(clnt_ecpoint,
                            EC_KEY_get0_public_key(clnt_pub_pkey->pkey.ec)) == 0)
                                {
                                SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                        ERR_R_EC_LIB);
                                goto err;
                                }
                        ret = 2; /* Skip certificate verify processing */
                        }
                else
                        {
                        /* Get client's public key from encoded point
                         * in the ClientKeyExchange message.
                         */
                        if ((bn_ctx = BN_CTX_new()) == NULL)
                                {
                                SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                    ERR_R_MALLOC_FAILURE);
                                goto err;
                                }

                        /* Get encoded point length */
                        i = *p; 
                        p += 1;
                        if (EC_POINT_oct2point(group, 
                            clnt_ecpoint, p, i, bn_ctx) == 0)
                                {
                                SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                    ERR_R_EC_LIB);
                                goto err;
                                }
                        /* p is pointing to somewhere in the buffer
                         * currently, so set it to the start 
                         */ 
                        p=(unsigned char *)s->init_buf->data;
                        }

                /* Compute the shared pre-master secret */
                field_size = EC_GROUP_get_degree(group);
                if (field_size <= 0)
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE, 
                               ERR_R_ECDH_LIB);
                        goto err;
                        }
                i = ECDH_compute_key(p, (field_size+7)/8, clnt_ecpoint, srvr_ecdh, NULL);
                if (i <= 0)
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                            ERR_R_ECDH_LIB);
                        goto err;
                        }

                EVP_PKEY_free(clnt_pub_pkey);
                EC_POINT_free(clnt_ecpoint);
                EC_KEY_free(srvr_ecdh);
                BN_CTX_free(bn_ctx);
                EC_KEY_free(s->s3->tmp.ecdh);
                s->s3->tmp.ecdh = NULL; 

                /* Compute the master secret */
                s->session->master_key_length = s->method->ssl3_enc-> \
                    generate_master_secret(s, s->session->master_key, p, i);
                
                OPENSSL_cleanse(p, i);
                return (ret);
                }
        else
#endif
#ifndef OPENSSL_NO_PSK
                if (alg_k & SSL_kPSK)
                        {
                        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;
                        char tmp_id[PSK_MAX_IDENTITY_LEN+1];

                        al=SSL_AD_HANDSHAKE_FAILURE;

                        n2s(p,i);
                        if (n != i+2)
                                {
                                SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                        SSL_R_LENGTH_MISMATCH);
                                goto psk_err;
                                }
                        if (i > PSK_MAX_IDENTITY_LEN)
                                {
                                SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                        SSL_R_DATA_LENGTH_TOO_LONG);
                                goto psk_err;
                                }
                        if (s->psk_server_callback == NULL)
                                {
                                SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                       SSL_R_PSK_NO_SERVER_CB);
                                goto psk_err;
                                }

                        /* Create guaranteed NULL-terminated identity
                         * string for the callback */
                        memcpy(tmp_id, p, i);
                        memset(tmp_id+i, 0, PSK_MAX_IDENTITY_LEN+1-i);
                        psk_len = s->psk_server_callback(s, tmp_id,
                                psk_or_pre_ms, sizeof(psk_or_pre_ms));
                        OPENSSL_cleanse(tmp_id, PSK_MAX_IDENTITY_LEN+1);

                        if (psk_len > PSK_MAX_PSK_LEN)
                                {
                                SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                        ERR_R_INTERNAL_ERROR);
                                goto psk_err;
                                }
                        else if (psk_len == 0)
                                {
                                /* PSK related to the given identity not found */
                                SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                       SSL_R_PSK_IDENTITY_NOT_FOUND);
                                al=SSL_AD_UNKNOWN_PSK_IDENTITY;
                                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 != NULL)
                                OPENSSL_free(s->session->psk_identity);
                        s->session->psk_identity = BUF_strdup((char *)p);
                        if (s->session->psk_identity == NULL)
                                {
                                SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                        ERR_R_MALLOC_FAILURE);
                                goto psk_err;
                                }

                        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_SSL3_GET_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);
                        psk_err = 0;
                psk_err:
                        OPENSSL_cleanse(psk_or_pre_ms, sizeof(psk_or_pre_ms));
                        if (psk_err != 0)
                                goto f_err;
                        }
                else
#endif
                if (alg_k & SSL_kGOST) 
                        {
                        int ret = 0;
                        EVP_PKEY_CTX *pkey_ctx;
                        EVP_PKEY *client_pub_pkey = NULL, *pk = NULL;
                        unsigned char premaster_secret[32], *start;
                        size_t outlen=32, inlen;
                        unsigned long alg_a;

                        /* Get our certificate private key*/
                        alg_a = s->s3->tmp.new_cipher->algorithm_auth;
                        if (alg_a & SSL_aGOST94)
                                pk = s->cert->pkeys[SSL_PKEY_GOST94].privatekey;
                        else if (alg_a & SSL_aGOST01)
                                pk = s->cert->pkeys[SSL_PKEY_GOST01].privatekey;

                        pkey_ctx = EVP_PKEY_CTX_new(pk,NULL);
                        EVP_PKEY_decrypt_init(pkey_ctx);
                        /* If client certificate is present and is of the same type, maybe
                         * use it for key exchange.  Don't mind errors from
                         * EVP_PKEY_derive_set_peer, because it is completely valid to use
                         * a client certificate for authorization only. */
                        client_pub_pkey = X509_get_pubkey(s->session->peer);
                        if (client_pub_pkey)
                                {
                                if (EVP_PKEY_derive_set_peer(pkey_ctx, client_pub_pkey) <= 0)
                                        ERR_clear_error();
                                }
                        /* Decrypt session key */
                        if ((*p!=( V_ASN1_SEQUENCE| V_ASN1_CONSTRUCTED))) 
                                {
                                SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_DECRYPTION_FAILED);
                                goto gerr;
                                }
                        if (p[1] == 0x81)
                                {
                                start = p+3;
                                inlen = p[2];
                                }
                        else if (p[1] < 0x80)
                                {
                                start = p+2;
                                inlen = p[1];
                                }
                        else
                                {
                                SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_DECRYPTION_FAILED);
                                goto gerr;
                                }
                        if (EVP_PKEY_decrypt(pkey_ctx,premaster_secret,&outlen,start,inlen) <=0) 

                                {
                                SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_DECRYPTION_FAILED);
                                goto gerr;
                                }
                        /* Generate master secret */
                        s->session->master_key_length=
                                s->method->ssl3_enc->generate_master_secret(s,
                                        s->session->master_key,premaster_secret,32);
                        /* Check if pubkey from client certificate was used */
                        if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, -1, EVP_PKEY_CTRL_PEER_KEY, 2, NULL) > 0)
                                ret = 2;
                        else
                                ret = 1;
                gerr:
                        EVP_PKEY_free(client_pub_pkey);
                        EVP_PKEY_CTX_free(pkey_ctx);
                        if (ret)
                                return ret;
                        else
                                goto err;
                        }
                else
                {
                al=SSL_AD_HANDSHAKE_FAILURE;
                SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                SSL_R_UNKNOWN_CIPHER_TYPE);
                goto f_err;
                }

        return(1);
f_err:
        ssl3_send_alert(s,SSL3_AL_FATAL,al);
#if !defined(OPENSSL_NO_DH) || !defined(OPENSSL_NO_RSA) || !defined(OPENSSL_NO_ECDH)
err:
#endif
#ifndef OPENSSL_NO_ECDH
        EVP_PKEY_free(clnt_pub_pkey);
        EC_POINT_free(clnt_ecpoint);
        if (srvr_ecdh != NULL) 
                EC_KEY_free(srvr_ecdh);
        BN_CTX_free(bn_ctx);
#endif
        return(-1);
        }

int ssl3_get_cert_verify(SSL *s)
        {
        EVP_PKEY *pkey=NULL;
        unsigned char *p;
        int al,ok,ret=0;
        long n;
        int type=0,i,j;
        X509 *peer;

        n=s->method->ssl_get_message(s,
                SSL3_ST_SR_CERT_VRFY_A,
                SSL3_ST_SR_CERT_VRFY_B,
                -1,
                514, /* 514? */
                &ok);

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

        if (s->session->peer != NULL)
                {
                peer=s->session->peer;
                pkey=X509_get_pubkey(peer);
                type=X509_certificate_type(peer,pkey);
                }
        else
                {
                peer=NULL;
                pkey=NULL;
                }

        if (s->s3->tmp.message_type != SSL3_MT_CERTIFICATE_VERIFY)
                {
                s->s3->tmp.reuse_message=1;
                if ((peer != NULL) && (type | EVP_PKT_SIGN))
                        {
                        al=SSL_AD_UNEXPECTED_MESSAGE;
                        SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_MISSING_VERIFY_MESSAGE);
                        goto f_err;
                        }
                ret=1;
                goto end;
                }

        if (peer == NULL)
                {
                SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_NO_CLIENT_CERT_RECEIVED);
                al=SSL_AD_UNEXPECTED_MESSAGE;
                goto f_err;
                }

        if (!(type & EVP_PKT_SIGN))
                {
                SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_SIGNATURE_FOR_NON_SIGNING_CERTIFICATE);
                al=SSL_AD_ILLEGAL_PARAMETER;
                goto f_err;
                }

        if (s->s3->change_cipher_spec)
                {
                SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_CCS_RECEIVED_EARLY);
                al=SSL_AD_UNEXPECTED_MESSAGE;
                goto f_err;
                }

        /* we now have a signature that we need to verify */
        p=(unsigned char *)s->init_msg;
        /* Check for broken implementations of GOST ciphersuites */
        /* If key is GOST and n is exactly 64, it is bare
         * signature without length field */
        if (n==64 && (pkey->type==NID_id_GostR3410_94 ||
                pkey->type == NID_id_GostR3410_2001) )
                {
                i=64;
                } 
        else 
                {       
                n2s(p,i);
                n-=2;
                if (i > n)
                        {
                        SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_LENGTH_MISMATCH);
                        al=SSL_AD_DECODE_ERROR;
                        goto f_err;
                        }
        }
        j=EVP_PKEY_size(pkey);
        if ((i > j) || (n > j) || (n <= 0))
                {
                SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_WRONG_SIGNATURE_SIZE);
                al=SSL_AD_DECODE_ERROR;
                goto f_err;
                }

#ifndef OPENSSL_NO_RSA 
        if (pkey->type == EVP_PKEY_RSA)
                {
                i=RSA_verify(NID_md5_sha1, s->s3->tmp.cert_verify_md,
                        MD5_DIGEST_LENGTH+SHA_DIGEST_LENGTH, p, i, 
                                                        pkey->pkey.rsa);
                if (i < 0)
                        {
                        al=SSL_AD_DECRYPT_ERROR;
                        SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_BAD_RSA_DECRYPT);
                        goto f_err;
                        }
                if (i == 0)
                        {
                        al=SSL_AD_DECRYPT_ERROR;
                        SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_BAD_RSA_SIGNATURE);
                        goto f_err;
                        }
                }
        else
#endif
#ifndef OPENSSL_NO_DSA
                if (pkey->type == EVP_PKEY_DSA)
                {
                j=DSA_verify(pkey->save_type,
                        &(s->s3->tmp.cert_verify_md[MD5_DIGEST_LENGTH]),
                        SHA_DIGEST_LENGTH,p,i,pkey->pkey.dsa);
                if (j <= 0)
                        {
                        /* bad signature */
                        al=SSL_AD_DECRYPT_ERROR;
                        SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_BAD_DSA_SIGNATURE);
                        goto f_err;
                        }
                }
        else
#endif
#ifndef OPENSSL_NO_ECDSA
                if (pkey->type == EVP_PKEY_EC)
                {
                j=ECDSA_verify(pkey->save_type,
                        &(s->s3->tmp.cert_verify_md[MD5_DIGEST_LENGTH]),
                        SHA_DIGEST_LENGTH,p,i,pkey->pkey.ec);
                if (j <= 0)
                        {
                        /* bad signature */
                        al=SSL_AD_DECRYPT_ERROR;
                        SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,
                            SSL_R_BAD_ECDSA_SIGNATURE);
                        goto f_err;
                        }
                }
        else
#endif
        if (pkey->type == NID_id_GostR3410_94 || pkey->type == NID_id_GostR3410_2001)
                {   unsigned char signature[64];
                        int idx;
                        EVP_PKEY_CTX *pctx = EVP_PKEY_CTX_new(pkey,NULL);
                        EVP_PKEY_verify_init(pctx);
                        if (i!=64) {
                                fprintf(stderr,"GOST signature length is %d",i);
                        }       
                        for (idx=0;idx<64;idx++) {
                                signature[63-idx]=p[idx];
                        }       
                        j=EVP_PKEY_verify(pctx,signature,64,s->s3->tmp.cert_verify_md,32);
                        EVP_PKEY_CTX_free(pctx);
                        if (j<=0) 
                                {
                                al=SSL_AD_DECRYPT_ERROR;
                                SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,
                                        SSL_R_BAD_ECDSA_SIGNATURE);
                                goto f_err;
                                }       
                }
        else    
                {
                SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,ERR_R_INTERNAL_ERROR);
                al=SSL_AD_UNSUPPORTED_CERTIFICATE;
                goto f_err;
                }


        ret=1;
        if (0)
                {
f_err:
                ssl3_send_alert(s,SSL3_AL_FATAL,al);
                }
end:
        EVP_PKEY_free(pkey);
        return(ret);
        }

int ssl3_get_client_certificate(SSL *s)
        {
        int i,ok,al,ret= -1;
        X509 *x=NULL;
        unsigned long l,nc,llen,n;
        const unsigned char *p,*q;
        unsigned char *d;
        STACK_OF(X509) *sk=NULL;

        n=s->method->ssl_get_message(s,
                SSL3_ST_SR_CERT_A,
                SSL3_ST_SR_CERT_B,
                -1,
                s->max_cert_list,
                &ok);

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

        if      (s->s3->tmp.message_type == SSL3_MT_CLIENT_KEY_EXCHANGE)
                {
                if (    (s->verify_mode & SSL_VERIFY_PEER) &&
                        (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT))
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE);
                        al=SSL_AD_HANDSHAKE_FAILURE;
                        goto f_err;
                        }
                /* If tls asked for a client cert, the client must return a 0 list */
                if ((s->version > SSL3_VERSION) && s->s3->tmp.cert_request)
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,SSL_R_TLS_PEER_DID_NOT_RESPOND_WITH_CERTIFICATE_LIST);
                        al=SSL_AD_UNEXPECTED_MESSAGE;
                        goto f_err;
                        }
                s->s3->tmp.reuse_message=1;
                return(1);
                }

        if (s->s3->tmp.message_type != SSL3_MT_CERTIFICATE)
                {
                al=SSL_AD_UNEXPECTED_MESSAGE;
                SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,SSL_R_WRONG_MESSAGE_TYPE);
                goto f_err;
                }
        p=d=(unsigned char *)s->init_msg;

        if ((sk=sk_X509_new_null()) == NULL)
                {
                SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,ERR_R_MALLOC_FAILURE);
                goto err;
                }

        n2l3(p,llen);
        if (llen+3 != n)
                {
                al=SSL_AD_DECODE_ERROR;
                SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,SSL_R_LENGTH_MISMATCH);
                goto f_err;
                }
        for (nc=0; nc<llen; )
                {
                n2l3(p,l);
                if ((l+nc+3) > llen)
                        {
                        al=SSL_AD_DECODE_ERROR;
                        SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,SSL_R_CERT_LENGTH_MISMATCH);
                        goto f_err;
                        }

                q=p;
                x=d2i_X509(NULL,&p,l);
                if (x == NULL)
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,ERR_R_ASN1_LIB);
                        goto err;
                        }
                if (p != (q+l))
                        {
                        al=SSL_AD_DECODE_ERROR;
                        SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,SSL_R_CERT_LENGTH_MISMATCH);
                        goto f_err;
                        }
                if (!sk_X509_push(sk,x))
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,ERR_R_MALLOC_FAILURE);
                        goto err;
                        }
                x=NULL;
                nc+=l+3;
                }

        if (sk_X509_num(sk) <= 0)
                {
                /* TLS does not mind 0 certs returned */
                if (s->version == SSL3_VERSION)
                        {
                        al=SSL_AD_HANDSHAKE_FAILURE;
                        SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,SSL_R_NO_CERTIFICATES_RETURNED);
                        goto f_err;
                        }
                /* Fail for TLS only if we required a certificate */
                else if ((s->verify_mode & SSL_VERIFY_PEER) &&
                         (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT))
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE);
                        al=SSL_AD_HANDSHAKE_FAILURE;
                        goto f_err;
                        }
                }
        else
                {
                i=ssl_verify_cert_chain(s,sk);
                if (i <= 0)
                        {
                        al=ssl_verify_alarm_type(s->verify_result);
                        SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,SSL_R_NO_CERTIFICATE_RETURNED);
                        goto f_err;
                        }
                }

        if (s->session->peer != NULL) /* This should not be needed */
                X509_free(s->session->peer);
        s->session->peer=sk_X509_shift(sk);
        s->session->verify_result = s->verify_result;

        /* With the current implementation, sess_cert will always be NULL
         * when we arrive here. */
        if (s->session->sess_cert == NULL)
                {
                s->session->sess_cert = ssl_sess_cert_new();
                if (s->session->sess_cert == NULL)
                        {
                        SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE, ERR_R_MALLOC_FAILURE);
                        goto err;
                        }
                }
        if (s->session->sess_cert->cert_chain != NULL)
                sk_X509_pop_free(s->session->sess_cert->cert_chain, X509_free);
        s->session->sess_cert->cert_chain=sk;
        /* Inconsistency alert: cert_chain does *not* include the
         * peer's own certificate, while we do include it in s3_clnt.c */

        sk=NULL;

        ret=1;
        if (0)
                {
f_err:
                ssl3_send_alert(s,SSL3_AL_FATAL,al);
                }
err:
        if (x != NULL) X509_free(x);
        if (sk != NULL) sk_X509_pop_free(sk,X509_free);
        return(ret);
        }

int ssl3_send_server_certificate(SSL *s)
        {
        unsigned long l;
        X509 *x;

        if (s->state == SSL3_ST_SW_CERT_A)
                {
                x=ssl_get_server_send_cert(s);
                if (x == NULL)
                        {
                        /* VRS: allow null cert if auth == KRB5 */
                        if ((s->s3->tmp.new_cipher->algorithm_auth != SSL_aKRB5) ||
                            (s->s3->tmp.new_cipher->algorithm_mkey & SSL_kKRB5))
                                {
                                SSLerr(SSL_F_SSL3_SEND_SERVER_CERTIFICATE,ERR_R_INTERNAL_ERROR);
                                return(0);
                                }
                        }

                l=ssl3_output_cert_chain(s,x);
                s->state=SSL3_ST_SW_CERT_B;
                s->init_num=(int)l;
                s->init_off=0;
                }

        /* SSL3_ST_SW_CERT_B */
        return(ssl3_do_write(s,SSL3_RT_HANDSHAKE));
        }
#ifndef OPENSSL_NO_TLSEXT
int ssl3_send_newsession_ticket(SSL *s)
        {
        if (s->state == SSL3_ST_SW_SESSION_TICKET_A)
                {
                unsigned char *p, *senc, *macstart;
                int len, slen;
                unsigned int hlen;
                EVP_CIPHER_CTX ctx;
                HMAC_CTX hctx;
                SSL_CTX *tctx = s->initial_ctx;
                unsigned char iv[EVP_MAX_IV_LENGTH];
                unsigned char key_name[16];

                /* get session encoding length */
                slen = i2d_SSL_SESSION(s->session, NULL);
                /* Some length values are 16 bits, so forget it if session is
                 * too long
                 */
                if (slen > 0xFF00)
                        return -1;
                /* Grow buffer if need be: the length calculation is as
                 * follows 1 (size of message name) + 3 (message length
                 * bytes) + 4 (ticket lifetime hint) + 2 (ticket length) +
                 * 16 (key name) + max_iv_len (iv length) +
                 * session_length + max_enc_block_size (max encrypted session
                 * length) + max_md_size (HMAC).
                 */
                if (!BUF_MEM_grow(s->init_buf,
                        26 + EVP_MAX_IV_LENGTH + EVP_MAX_BLOCK_LENGTH +
                        EVP_MAX_MD_SIZE + slen))
                        return -1;
                senc = OPENSSL_malloc(slen);
                if (!senc)
                        return -1;
                p = senc;
                i2d_SSL_SESSION(s->session, &p);

                p=(unsigned char *)s->init_buf->data;
                /* do the header */
                *(p++)=SSL3_MT_NEWSESSION_TICKET;
                /* Skip message length for now */
                p += 3;
                EVP_CIPHER_CTX_init(&ctx);
                HMAC_CTX_init(&hctx);
                /* Initialize HMAC and cipher contexts. If callback present
                 * it does all the work otherwise use generated values
                 * from parent ctx.
                 */
                if (tctx->tlsext_ticket_key_cb)
                        {
                        if (tctx->tlsext_ticket_key_cb(s, key_name, iv, &ctx,
                                                         &hctx, 1) < 0)
                                {
                                OPENSSL_free(senc);
                                return -1;
                                }
                        }
                else
                        {
                        RAND_pseudo_bytes(iv, 16);
                        EVP_EncryptInit_ex(&ctx, EVP_aes_128_cbc(), NULL,
                                        tctx->tlsext_tick_aes_key, iv);
                        HMAC_Init_ex(&hctx, tctx->tlsext_tick_hmac_key, 16,
                                        tlsext_tick_md(), NULL);
                        memcpy(key_name, tctx->tlsext_tick_key_name, 16);
                        }
                l2n(s->session->tlsext_tick_lifetime_hint, p);
                /* Skip ticket length for now */
                p += 2;
                /* Output key name */
                macstart = p;
                memcpy(p, key_name, 16);
                p += 16;
                /* output IV */
                memcpy(p, iv, EVP_CIPHER_CTX_iv_length(&ctx));
                p += EVP_CIPHER_CTX_iv_length(&ctx);
                /* Encrypt session data */
                EVP_EncryptUpdate(&ctx, p, &len, senc, slen);
                p += len;
                EVP_EncryptFinal(&ctx, p, &len);
                p += len;
                EVP_CIPHER_CTX_cleanup(&ctx);

                HMAC_Update(&hctx, macstart, p - macstart);
                HMAC_Final(&hctx, p, &hlen);
                HMAC_CTX_cleanup(&hctx);

                p += hlen;
                /* Now write out lengths: p points to end of data written */
                /* Total length */
                len = p - (unsigned char *)s->init_buf->data;
                p=(unsigned char *)s->init_buf->data + 1;
                l2n3(len - 4, p); /* Message length */
                p += 4;
                s2n(len - 10, p);  /* Ticket length */

                /* number of bytes to write */
                s->init_num= len;
                s->state=SSL3_ST_SW_SESSION_TICKET_B;
                s->init_off=0;
                OPENSSL_free(senc);
                }

        /* SSL3_ST_SW_SESSION_TICKET_B */
        return(ssl3_do_write(s,SSL3_RT_HANDSHAKE));
        }

int ssl3_send_cert_status(SSL *s)
        {
        if (s->state == SSL3_ST_SW_CERT_STATUS_A)
                {
                unsigned char *p;
                /* Grow buffer if need be: the length calculation is as
                 * follows 1 (message type) + 3 (message length) +
                 * 1 (ocsp response type) + 3 (ocsp response length)
                 * + (ocsp response)
                 */
                if (!BUF_MEM_grow(s->init_buf, 8 + s->tlsext_ocsp_resplen))
                        return -1;

                p=(unsigned char *)s->init_buf->data;

                /* do the header */
                *(p++)=SSL3_MT_CERTIFICATE_STATUS;
                /* message length */
                l2n3(s->tlsext_ocsp_resplen + 4, p);
                /* status type */
                *(p++)= s->tlsext_status_type;
                /* length of OCSP response */
                l2n3(s->tlsext_ocsp_resplen, p);
                /* actual response */
                memcpy(p, s->tlsext_ocsp_resp, s->tlsext_ocsp_resplen);
                /* number of bytes to write */
                s->init_num = 8 + s->tlsext_ocsp_resplen;
                s->state=SSL3_ST_SW_CERT_STATUS_B;
                s->init_off = 0;
                }

        /* SSL3_ST_SW_CERT_STATUS_B */
        return(ssl3_do_write(s,SSL3_RT_HANDSHAKE));
        }

# ifndef OPENSSL_NO_NPN
/* ssl3_get_next_proto reads a Next Protocol Negotiation handshake message. It
 * sets the next_proto member in s if found */
int ssl3_get_next_proto(SSL *s)
        {
        int ok;
        int proto_len, padding_len;
        long n;
        const unsigned char *p;

        /* Clients cannot send a NextProtocol message if we didn't see the
         * extension in their ClientHello */
        if (!s->s3->next_proto_neg_seen)
                {
                SSLerr(SSL_F_SSL3_GET_NEXT_PROTO,SSL_R_GOT_NEXT_PROTO_WITHOUT_EXTENSION);
                return -1;
                }

        n=s->method->ssl_get_message(s,
                SSL3_ST_SR_NEXT_PROTO_A,
                SSL3_ST_SR_NEXT_PROTO_B,
                SSL3_MT_NEXT_PROTO,
                514,  /* See the payload format below */
                &ok);

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

        /* s->state doesn't reflect whether ChangeCipherSpec has been received
         * in this handshake, but s->s3->change_cipher_spec does (will be reset
         * by ssl3_get_finished). */
        if (!s->s3->change_cipher_spec)
                {
                SSLerr(SSL_F_SSL3_GET_NEXT_PROTO,SSL_R_GOT_NEXT_PROTO_BEFORE_A_CCS);
                return -1;
                }

        if (n < 2)
                return 0;  /* The body must be > 1 bytes long */

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

        /* The payload looks like:
         *   uint8 proto_len;
         *   uint8 proto[proto_len];
         *   uint8 padding_len;
         *   uint8 padding[padding_len];
         */
        proto_len = p[0];
        if (proto_len + 2 > s->init_num)
                return 0;
        padding_len = p[proto_len + 1];
        if (proto_len + padding_len + 2 != s->init_num)
                return 0;

        s->next_proto_negotiated = OPENSSL_malloc(proto_len);
        if (!s->next_proto_negotiated)
                {
                SSLerr(SSL_F_SSL3_GET_NEXT_PROTO,ERR_R_MALLOC_FAILURE);
                return 0;
                }
        memcpy(s->next_proto_negotiated, p + 1, proto_len);
        s->next_proto_negotiated_len = proto_len;

        return 1;
        }
# endif
#endif