/* ssl/d1_srvr.c */

 /* 

  * DTLS implementation written by Nagendra Modadugu

  * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.  

  */

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

  * Copyright (c) 1999-2005 The OpenSSL Project.  All rights reserved.

  *

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

  * modification, are permitted provided that the following conditions

  * are met:

  *

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

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

  *

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

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

  *    the documentation and/or other materials provided with the

  *    distribution.

  *

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

  *    software must display the following acknowledgment:

  *    "This product includes software developed by the OpenSSL Project

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

  *

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

  *    endorse or promote products derived from this software without

  *    prior written permission. For written permission, please contact

  *    openssl-core@OpenSSL.org.

  *

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

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

  *    permission of the OpenSSL Project.

  *

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

  *    acknowledgment:

  *    "This product includes software developed by the OpenSSL Project

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

  *

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

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

  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

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

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

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

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

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

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

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

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

  * OF THE POSSIBILITY OF SUCH DAMAGE.

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

  *

  * This product includes cryptographic software written by Eric Young

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

  * Hudson (tjh@cryptsoft.com).

  *

  */

 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)

  * All rights reserved.

  *

  * This package is an SSL implementation written

  * by Eric Young (eay@cryptsoft.com).

  * The implementation was written so as to conform with Netscapes SSL.

  * 

  * This library is free for commercial and non-commercial use as long as

  * the following conditions are aheared to.  The following conditions

  * apply to all code found in this distribution, be it the RC4, RSA,

  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation

  * included with this distribution is covered by the same copyright terms

  * except that the holder is Tim Hudson (tjh@cryptsoft.com).

  * 

  * Copyright remains Eric Young's, and as such any Copyright notices in

  * the code are not to be removed.

  * If this package is used in a product, Eric Young should be given attribution

  * as the author of the parts of the library used.

  * This can be in the form of a textual message at program startup or

  * in documentation (online or textual) provided with the package.

  * 

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

  * modification, are permitted provided that the following conditions

  * are met:

  * 1. Redistributions of source code must retain the copyright

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

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

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

  *    documentation and/or other materials provided with the distribution.

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

  *    must display the following acknowledgement:

  *    "This product includes cryptographic software written by

  *     Eric Young (eay@cryptsoft.com)"

  *    The word 'cryptographic' can be left out if the rouines from the library

  *    being used are not cryptographic related :-).

  * 4. If you include any Windows specific code (or a derivative thereof) from 

  *    the apps directory (application code) you must include an acknowledgement:

  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"

  * 

  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND

  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE

  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

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

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

  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

  * SUCH DAMAGE.

  * 

  * The licence and distribution terms for any publically available version or

  * derivative of this code cannot be changed.  i.e. this code cannot simply be

  * copied and put under another distribution licence

  * [including the GNU Public Licence.]

  */

 /*

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

  */

 #include <stdio.h>

 #include "ssl_locl.h"

 #include <openssl/buffer.h>

 #include <openssl/rand.h>

 #include <openssl/objects.h>

 #include <openssl/evp.h>

 #include <openssl/x509.h>

 #include <openssl/md5.h>

 #ifndef OPENSSL_NO_DH

 #include <openssl/dh.h>

 #endif

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

 #include "libssl_wsd.h"

 #endif

 #ifdef EMULATOR

 	GET_STATIC_VAR_FROM_TLS(DTLSv1_server_method_data,d1_srvr,SSL_METHOD)

 	#define DTLSv1_server_method_data (*GET_WSD_VAR_NAME(DTLSv1_server_method_data,d1_srvr,s)())

 #endif

 static SSL_METHOD *dtls1_get_server_method(int ver);

 static int dtls1_send_hello_verify_request(SSL *s);

 static SSL_METHOD *dtls1_get_server_method(int ver)

 	{

 	if (ver == DTLS1_VERSION)

 		return(DTLSv1_server_method());

 	else

 		return(NULL);

 	}

 EXPORT_C IMPLEMENT_dtls1_meth_func(DTLSv1_server_method,

 			dtls1_accept,

 			ssl_undefined_function,

 			dtls1_get_server_method)

 int dtls1_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_DTLS1_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 & 0xff00) != (DTLS1_VERSION & 0xff00))

 				{

 				SSLerr(SSL_F_DTLS1_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;

 				}

             if ( (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE))

                 s->d1->send_cookie = 1;

             else

                 s->d1->send_cookie = 0;

 			break;

 		case SSL3_ST_SW_HELLO_REQ_A:

 		case SSL3_ST_SW_HELLO_REQ_B:

 			s->shutdown=0;

 			ret=dtls1_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;

 			if ( s->d1->send_cookie)

 				s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A;

 			else

 				s->state = SSL3_ST_SW_SRVR_HELLO_A;

 			s->init_num=0;

 			break;

 		case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A:

 		case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B:

 			ret = dtls1_send_hello_verify_request(s);

 			if ( ret <= 0) goto end;

 			s->d1->send_cookie = 0;

 			s->state=SSL3_ST_SW_FLUSH;

 			s->s3->tmp.next_state=SSL3_ST_SR_CLNT_HELLO_A;

 			/* HelloVerifyRequests resets Finished MAC */

 			if (s->client_version != DTLS1_BAD_VER)

 				ssl3_init_finished_mac(s);

 			break;

 		case SSL3_ST_SW_SRVR_HELLO_A:

 		case SSL3_ST_SW_SRVR_HELLO_B:

 			ret=dtls1_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 */

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

 				{

 				ret=dtls1_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 */

 			if (s->s3->tmp.use_rsa_tmp

 			    || (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=dtls1_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=dtls1_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=dtls1_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 {

 				/* could be sent for a DH cert, even if we

 				 * have not asked for it :-) */

 				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;

 			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=dtls1_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;

 				}

 			dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);

 			break;

 		case SSL3_ST_SW_FINISHED_A:

 		case SSL3_ST_SW_FINISHED_B:

 			ret=dtls1_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);

 #if 0

 			BUF_MEM_free(s->init_buf);

 			s->init_buf=NULL;

 #endif

 			/* 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=dtls1_accept;

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

 				}

 			ret = 1;

 			/* done handshaking, next message is client hello */

 			s->d1->handshake_read_seq = 0;

 			/* next message is server hello */

 			s->d1->handshake_write_seq = 0;

 			goto end;

 			/* break; */

 		default:

 			SSLerr(SSL_F_DTLS1_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 dtls1_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 = dtls1_set_message_header(s, p, SSL3_MT_HELLO_REQUEST, 0, 0, 0);

 		s->state=SSL3_ST_SW_HELLO_REQ_B;

 		/* number of bytes to write */

 		s->init_num=DTLS1_HM_HEADER_LENGTH;

 		s->init_off=0;

 		/* no need to buffer this message, since there are no retransmit 

 		 * requests for it */

 		}

 	/* SSL3_ST_SW_HELLO_REQ_B */

 	return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));

 	}

 int dtls1_send_hello_verify_request(SSL *s)

 	{

 	unsigned int msg_len;

 	unsigned char *msg, *buf, *p;

 	if (s->state == DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A)

 		{

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

 		msg = p = &(buf[DTLS1_HM_HEADER_LENGTH]);

 		if (s->client_version == DTLS1_BAD_VER)

 			*(p++) = DTLS1_BAD_VER>>8,

 			*(p++) = DTLS1_BAD_VER&0xff;

 		else

 			*(p++) = s->version >> 8,

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

 		if (s->ctx->app_gen_cookie_cb != NULL &&

 		    s->ctx->app_gen_cookie_cb(s, s->d1->cookie, 

 		    &(s->d1->cookie_len)) == 0)

 			{

 			SSLerr(SSL_F_DTLS1_SEND_HELLO_VERIFY_REQUEST,ERR_R_INTERNAL_ERROR);

 			return 0;

 			}

 		/* else the cookie is assumed to have 

 		 * been initialized by the application */

 		*(p++) = (unsigned char) s->d1->cookie_len;

 		memcpy(p, s->d1->cookie, s->d1->cookie_len);

 		p += s->d1->cookie_len;

 		msg_len = p - msg;

 		dtls1_set_message_header(s, buf,

 			DTLS1_MT_HELLO_VERIFY_REQUEST, msg_len, 0, msg_len);

 		s->state=DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B;

 		/* number of bytes to write */

 		s->init_num=p-buf;

 		s->init_off=0;

 		/* buffer the message to handle re-xmits */

 		dtls1_buffer_message(s, 0);

 		}

 	/* s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B */

 	return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));

 	}

 int dtls1_send_server_hello(SSL *s)

 	{

 	unsigned char *buf;

 	unsigned char *p,*d;

 	int i;

 	unsigned int sl;

 	unsigned long l,Time;

 	if (s->state == SSL3_ST_SW_SRVR_HELLO_A)

 		{

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

 		p=s->s3->server_random;

 		Time=(unsigned long)time(NULL);			/* Time */

 		l2n(Time,p);

 		RAND_pseudo_bytes(p,SSL3_RANDOM_SIZE-sizeof(Time));

 		/* Do the message type and length last */

 		d=p= &(buf[DTLS1_HM_HEADER_LENGTH]);

 		if (s->client_version == DTLS1_BAD_VER)

 			*(p++)=DTLS1_BAD_VER>>8,

 			*(p++)=DTLS1_BAD_VER&0xff;

 		else

 			*(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.

 		 */

 		if (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER))

 			s->session->session_id_length=0;

 		sl=s->session->session_id_length;

 		if (sl > sizeof s->session->session_id)

 			{

 			SSLerr(SSL_F_DTLS1_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

 		/* do the header */

 		l=(p-d);

 		d=buf;

 		d = dtls1_set_message_header(s, d, SSL3_MT_SERVER_HELLO, l, 0, l);

 		s->state=SSL3_ST_CW_CLNT_HELLO_B;

 		/* number of bytes to write */

 		s->init_num=p-buf;

 		s->init_off=0;

 		/* buffer the message to handle re-xmits */

 		dtls1_buffer_message(s, 0);

 		}

 	/* SSL3_ST_CW_CLNT_HELLO_B */

 	return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));

 	}

 int dtls1_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 = dtls1_set_message_header(s, p, SSL3_MT_SERVER_DONE, 0, 0, 0);

 		s->state=SSL3_ST_SW_SRVR_DONE_B;

 		/* number of bytes to write */

 		s->init_num=DTLS1_HM_HEADER_LENGTH;

 		s->init_off=0;

 		/* buffer the message to handle re-xmits */

 		dtls1_buffer_message(s, 0);

 		}

 	/* SSL3_ST_CW_CLNT_HELLO_B */

 	return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));

 	}

 int dtls1_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

 	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->algorithms & SSL_MKEY_MASK;

 		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_DTLS1_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_DTLS1_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_DTLS1_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_DTLS1_SEND_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);

 				goto err;

 				}

 			if ((dh=DHparams_dup(dhp)) == NULL)

 				{

 				SSLerr(SSL_F_DTLS1_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_DTLS1_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_DTLS1_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

 			{

 			al=SSL_AD_HANDSHAKE_FAILURE;

 			SSLerr(SSL_F_DTLS1_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->algorithms & SSL_aNULL))

 			{

 			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+DTLS1_HM_HEADER_LENGTH+kn))

 			{

 			SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_BUF);

 			goto err;

 			}

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

 		p= &(d[DTLS1_HM_HEADER_LENGTH]);

 		for (i=0; r[i] != NULL; i++)

 			{

 			s2n(nr[i],p);

 			BN_bn2bin(r[i],p);

 			p+=nr[i];

 			}

 		/* not anonymous */

 		if (pkey != NULL)

 			{

 			/* n is the length of the params, they start at

 			 * &(d[DTLS1_HM_HEADER_LENGTH]) 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[DTLS1_HM_HEADER_LENGTH]),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_DTLS1_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[DTLS1_HM_HEADER_LENGTH]),n);

 				if (!EVP_SignFinal(&md_ctx,&(p[2]),

 					(unsigned int *)&i,pkey))

 					{

 					SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_DSA);

 					goto err;

 					}

 				s2n(i,p);

 				n+=i+2;

 				}

 			else

 #endif

 				{

 				/* Is this error check actually needed? */

 				al=SSL_AD_HANDSHAKE_FAILURE;

 				SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_PKEY_TYPE);

 				goto f_err;

 				}

 			}

 		d = dtls1_set_message_header(s, d,

 			SSL3_MT_SERVER_KEY_EXCHANGE, n, 0, n);

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

 		 * it off */

 		s->init_num=n+DTLS1_HM_HEADER_LENGTH;

 		s->init_off=0;

 		/* buffer the message to handle re-xmits */

 		dtls1_buffer_message(s, 0);

 		}

 	s->state = SSL3_ST_SW_KEY_EXCH_B;

 	EVP_MD_CTX_cleanup(&md_ctx);

 	return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));

 f_err:

 	ssl3_send_alert(s,SSL3_AL_FATAL,al);

 err:

 	EVP_MD_CTX_cleanup(&md_ctx);

 	return(-1);

 	}

 int dtls1_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;

 	unsigned int msg_len;

 	if (s->state == SSL3_ST_SW_CERT_REQ_A)

 		{

 		buf=s->init_buf;

 		d=p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH]);

 		/* 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,DTLS1_HM_HEADER_LENGTH+n+j+2))

 					{

 					SSLerr(SSL_F_DTLS1_SEND_CERTIFICATE_REQUEST,ERR_R_BUF_LIB);

 					goto err;

 					}

 				p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH+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[DTLS1_HM_HEADER_LENGTH+off]);

 		s2n(nl,p);

 		d=(unsigned char *)buf->data;

 		*(d++)=SSL3_MT_CERTIFICATE_REQUEST;

 		l2n3(n,d);

 		s2n(s->d1->handshake_write_seq,d);

 		s->d1->handshake_write_seq++;

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

 		 * it off */

 		s->init_num=n+DTLS1_HM_HEADER_LENGTH;

 		s->init_off=0;

 #ifdef NETSCAPE_HANG_BUG

 /* XXX: what to do about this? */

 		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

 		/* XDTLS:  set message header ? */

 		msg_len = s->init_num - DTLS1_HM_HEADER_LENGTH;

 		dtls1_set_message_header(s, (void *)s->init_buf->data,

 			SSL3_MT_CERTIFICATE_REQUEST, msg_len, 0, msg_len);

 		/* buffer the message to handle re-xmits */

 		dtls1_buffer_message(s, 0);

 		s->state = SSL3_ST_SW_CERT_REQ_B;

 		}

 	/* SSL3_ST_SW_CERT_REQ_B */

 	return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));

 err:

 	return(-1);

 	}

 int dtls1_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 */

                         (s->s3->tmp.new_cipher->algorithms

                                 & (SSL_MKEY_MASK|SSL_AUTH_MASK))

                         != (SSL_aKRB5|SSL_kKRB5))

 			{

 			SSLerr(SSL_F_DTLS1_SEND_SERVER_CERTIFICATE,ERR_R_INTERNAL_ERROR);

 			return(0);

 			}

 		l=dtls1_output_cert_chain(s,x);

 		s->state=SSL3_ST_SW_CERT_B;

 		s->init_num=(int)l;

 		s->init_off=0;

 		/* buffer the message to handle re-xmits */

 		dtls1_buffer_message(s, 0);

 		}

 	/* SSL3_ST_SW_CERT_B */

 	return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));

 	}