/* ssl/s3_srvr.c */

/* 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) 1998-2005 The OpenSSL Project.  All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer. 

 *

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in

 *    the documentation and/or other materials provided with the

 *    distribution.

 *

 * 3. All advertising materials mentioning features or use of this

 *    software must display the following acknowledgment:

 *    "This product includes software developed by the OpenSSL Project

 *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"

 *

 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to

 *    endorse or promote products derived from this software without

 *    prior written permission. For written permission, please contact

 *    openssl-core@openssl.org.

 *

 * 5. Products derived from this software may not be called "OpenSSL"

 *    nor may "OpenSSL" appear in their names without prior written

 *    permission of the OpenSSL Project.

 *

 * 6. Redistributions of any form whatsoever must retain the following

 *    acknowledgment:

 *    "This product includes software developed by the OpenSSL Project

 *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"

 *

 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY

 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR

 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT

 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,

 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED

 * OF THE POSSIBILITY OF SUCH DAMAGE.

 * ====================================================================

 *

 * This product includes cryptographic software written by Eric Young

 * (eay@cryptsoft.com).  This product includes software written by Tim

 * Hudson (tjh@cryptsoft.com).

 *

 */

/* ====================================================================

 * Copyright 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.

 *

 */

/*

 © Portions copyright (c) 2006 Nokia Corporation.  All rights reserved.

 */

#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>

#if (defined(SYMBIAN) && (defined(__WINSCW__) || defined(__WINS__)))

#include "libssl_wsd.h"

#endif

#ifdef EMULATOR

	GET_STATIC_VAR_FROM_TLS(SSLv3_server_method_data,s3_srvr,SSL_METHOD)

	#define SSLv3_server_method_data (*GET_WSD_VAR_NAME(SSLv3_server_method_data,s3_srvr,s)())

#endif

static SSL_METHOD *ssl3_get_server_method(int ver);

#ifndef OPENSSL_NO_ECDH

static int nid2curve_id(int nid);

#endif

static SSL_METHOD *ssl3_get_server_method(int ver)

	{

	if (ver == SSL3_VERSION)

		return(SSLv3_server_method());

	else

		return(NULL);

	}

EXPORT_C 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 l,Time=(unsigned long)time(NULL);

	void (*cb)(const SSL *ssl,int type,int val)=NULL;

	long num1;

	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->new_session=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

				{

				/* 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->new_session = 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;

			if (s->hit)

				s->state=SSL3_ST_SW_CHANGE_A;

			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 or KRB5 */

			if (!(s->s3->tmp.new_cipher->algorithms & SSL_aNULL)

				&& !(s->s3->tmp.new_cipher->algorithms & SSL_aKRB5))

				{

				ret=ssl3_send_server_certificate(s);

				if (ret <= 0) goto end;

				}

			else

				skip=1;

			s->state=SSL3_ST_SW_KEY_EXCH_A;

			s->init_num=0;

			break;

		case SSL3_ST_SW_KEY_EXCH_A:

		case SSL3_ST_SW_KEY_EXCH_B:

			l=s->s3->tmp.new_cipher->algorithms;

			/* clear this, it may get reset by

			 * send_server_key_exchange */

			if ((s->options & SSL_OP_EPHEMERAL_RSA)

#ifndef OPENSSL_NO_KRB5

				&& !(l & SSL_KRB5)

#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

			 *

			 * 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

			    || (l & SSL_kECDHE)

			    || (l & (SSL_DH|SSL_kFZA))

			    || ((l & 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->algorithms & 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->algorithms & SSL_aKRB5))

				{

				/* 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:

			/* number of bytes to be flushed */

			num1=BIO_ctrl(s->wbio,BIO_CTRL_INFO,0,NULL);

			if (num1 > 0)

				{

				s->rwstate=SSL_WRITING;

				num1=BIO_flush(s->wbio);

				if (num1 <= 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.

				 */

				s->state=SSL3_ST_SR_FINISHED_A;

				s->init_num = 0;

				}

			else   

				{

				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

				 */ 

				s->method->ssl3_enc->cert_verify_mac(s,

				    &(s->s3->finish_dgst1),

				    &(s->s3->tmp.cert_verify_md[0]));

				s->method->ssl3_enc->cert_verify_mac(s,

				    &(s->s3->finish_dgst2),

				    &(s->s3->tmp.cert_verify_md[MD5_DIGEST_LENGTH]));

				}

			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;

			s->state=SSL3_ST_SR_FINISHED_A;

			s->init_num=0;

			break;

		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;

			if (s->hit)

				s->state=SSL_ST_OK;

			else

				s->state=SSL3_ST_SW_CHANGE_A;

			s->init_num=0;

			break;

		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)

				s->s3->tmp.next_state=SSL3_ST_SR_FINISHED_A;

			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->new_session == 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->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;

		}

	/* 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)

		{

		/* cookie stuff */

		cookie_len = *(p++);

		if ( (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) &&

			s->d1->send_cookie == 0)

			{

			/* HelloVerifyMessage has already been sent */

			if ( cookie_len != s->d1->cookie_len)

				{

				al = SSL_AD_HANDSHAKE_FAILURE;

				SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_COOKIE_MISMATCH);

				goto f_err;

				}

			}

		/* 

		 * 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;

				}

			}

		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)

			{

			if ((s->options & SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG) && (sk_SSL_CIPHER_num(ciphers) == 1))

				{

				/* Very bad for multi-threading.... */

				s->session->cipher=sk_SSL_CIPHER_value(ciphers, 0);

				}

			else

				{

				/* 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;

		}

	/* 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

	if (s->ctx->comp_methods != NULL)

		{ /* 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;

		}

#endif

	/* TLS does not mind if there is extra stuff */

#if 0   /* SSL 3.0 does not mind either, so we should disable this test

         * (was enabled in 0.9.6d through 0.9.6j and 0.9.7 through 0.9.7b,

         * in earlier SSLeay/OpenSSL releases this test existed but was buggy) */

	if (s->version == SSL3_VERSION)

		{

		if (p < (d+n))

			{

			/* wrong number of bytes,

			 * there could be more to follow */

			al=SSL_AD_DECODE_ERROR;

			SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_LENGTH_MISMATCH);

			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;