d1_pkt.c

		if (dest_maxlen > 0)
			{
            /* XDTLS:  In a pathalogical case, the Client Hello
             *  may be fragmented--don't always expect dest_maxlen bytes */
			if ( rr->length < dest_maxlen)
				{
#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
				/*
				 * for normal alerts rr->length is 2, while
				 * dest_maxlen is 7 if we were to handle this
				 * non-existing alert...
				 */
				FIX ME
#endif
				s->rstate=SSL_ST_READ_HEADER;
				rr->length = 0;
				goto start;
				}

			/* now move 'n' bytes: */
			for ( k = 0; k < dest_maxlen; k++)
				{
				dest[k] = rr->data[rr->off++];
				rr->length--;
				}
			*dest_len = dest_maxlen;
			}
		}

	/* s->d1->handshake_fragment_len == 12  iff  rr->type == SSL3_RT_HANDSHAKE;
	 * s->d1->alert_fragment_len == 7      iff  rr->type == SSL3_RT_ALERT.
	 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */

	/* If we are a client, check for an incoming 'Hello Request': */
	if ((!s->server) &&
		(s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
		(s->d1->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
		(s->session != NULL) && (s->session->cipher != NULL))
		{
		s->d1->handshake_fragment_len = 0;

		if ((s->d1->handshake_fragment[1] != 0) ||
			(s->d1->handshake_fragment[2] != 0) ||
			(s->d1->handshake_fragment[3] != 0))
			{
			al=SSL_AD_DECODE_ERROR;
			SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
			goto err;
			}

		/* no need to check sequence number on HELLO REQUEST messages */

		if (s->msg_callback)
			s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, 
				s->d1->handshake_fragment, 4, s, s->msg_callback_arg);

		if (SSL_is_init_finished(s) &&
			!(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
			!s->s3->renegotiate)
			{
			s->d1->handshake_read_seq++;
			s->new_session = 1;
			ssl3_renegotiate(s);
			if (ssl3_renegotiate_check(s))
				{
				i=s->handshake_func(s);
				if (i < 0) return(i);
				if (i == 0)
					{
					SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
					return(-1);
					}

				if (!(s->mode & SSL_MODE_AUTO_RETRY))
					{
					if (s->s3->rbuf.left == 0) /* no read-ahead left? */
						{
						BIO *bio;
						/* In the case where we try to read application data,
						 * but we trigger an SSL handshake, we return -1 with
						 * the retry option set.  Otherwise renegotiation may
						 * cause nasty problems in the blocking world */
						s->rwstate=SSL_READING;
						bio=SSL_get_rbio(s);
						BIO_clear_retry_flags(bio);
						BIO_set_retry_read(bio);
						return(-1);
						}
					}
				}
			}
		/* we either finished a handshake or ignored the request,
		 * now try again to obtain the (application) data we were asked for */
		goto start;
		}

	if (s->d1->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH)
		{
		int alert_level = s->d1->alert_fragment[0];
		int alert_descr = s->d1->alert_fragment[1];

		s->d1->alert_fragment_len = 0;

		if (s->msg_callback)
			s->msg_callback(0, s->version, SSL3_RT_ALERT, 
				s->d1->alert_fragment, 2, s, s->msg_callback_arg);

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

		if (cb != NULL)
			{
			j = (alert_level << 8) | alert_descr;
			cb(s, SSL_CB_READ_ALERT, j);
			}

		if (alert_level == 1) /* warning */
			{
			s->s3->warn_alert = alert_descr;
			if (alert_descr == SSL_AD_CLOSE_NOTIFY)
				{
#ifndef OPENSSL_NO_SCTP
				/* With SCTP and streams the socket may deliver app data
				 * after a close_notify alert. We have to check this
				 * first so that nothing gets discarded.
				 */
				if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
					BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s)))
					{
					s->d1->shutdown_received = 1;
					s->rwstate=SSL_READING;
					BIO_clear_retry_flags(SSL_get_rbio(s));
					BIO_set_retry_read(SSL_get_rbio(s));
					return -1;
					}
#endif
				s->shutdown |= SSL_RECEIVED_SHUTDOWN;
				return(0);
				}
#if 0
            /* XXX: this is a possible improvement in the future */
			/* now check if it's a missing record */
			if (alert_descr == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE)
				{
				unsigned short seq;
				unsigned int frag_off;
				unsigned char *p = &(s->d1->alert_fragment[2]);

				n2s(p, seq);
				n2l3(p, frag_off);

				dtls1_retransmit_message(s,
										 dtls1_get_queue_priority(frag->msg_header.seq, 0),
										 frag_off, &found);
				if ( ! found  && SSL_in_init(s))
					{
					/* fprintf( stderr,"in init = %d\n", SSL_in_init(s)); */
					/* requested a message not yet sent, 
					   send an alert ourselves */
					ssl3_send_alert(s,SSL3_AL_WARNING,
						DTLS1_AD_MISSING_HANDSHAKE_MESSAGE);
					}
				}
#endif
			}
		else if (alert_level == 2) /* fatal */
			{
			char tmp[16];

			s->rwstate=SSL_NOTHING;
			s->s3->fatal_alert = alert_descr;
			SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
			BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
			ERR_add_error_data(2,"SSL alert number ",tmp);
			s->shutdown|=SSL_RECEIVED_SHUTDOWN;
			SSL_CTX_remove_session(s->ctx,s->session);
			return(0);
			}
		else
			{
			al=SSL_AD_ILLEGAL_PARAMETER;
			SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
			goto f_err;
			}

		goto start;
		}

	if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
		{
		s->rwstate=SSL_NOTHING;
		rr->length=0;
		return(0);
		}

	if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
		{
		struct ccs_header_st ccs_hdr;
		unsigned int ccs_hdr_len = DTLS1_CCS_HEADER_LENGTH;

		dtls1_get_ccs_header(rr->data, &ccs_hdr);

		if (s->version == DTLS1_BAD_VER)
			ccs_hdr_len = 3;

		/* 'Change Cipher Spec' is just a single byte, so we know
		 * exactly what the record payload has to look like */
		/* XDTLS: check that epoch is consistent */
		if (	(rr->length != ccs_hdr_len) || 
			(rr->off != 0) || (rr->data[0] != SSL3_MT_CCS))
			{
			i=SSL_AD_ILLEGAL_PARAMETER;
			SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
			goto err;
			}

		rr->length=0;

		if (s->msg_callback)
			s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, 
				rr->data, 1, s, s->msg_callback_arg);

		/* We can't process a CCS now, because previous handshake
		 * messages are still missing, so just drop it.
		 */
		if (!s->d1->change_cipher_spec_ok)
			{
			goto start;
			}

		s->d1->change_cipher_spec_ok = 0;

		s->s3->change_cipher_spec=1;
		if (!ssl3_do_change_cipher_spec(s))
			goto err;

		/* do this whenever CCS is processed */
		dtls1_reset_seq_numbers(s, SSL3_CC_READ);

		if (s->version == DTLS1_BAD_VER)
			s->d1->handshake_read_seq++;

#ifndef OPENSSL_NO_SCTP
		/* Remember that a CCS has been received,
		 * so that an old key of SCTP-Auth can be
		 * deleted when a CCS is sent. Will be ignored
		 * if no SCTP is used
		 */
		BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL);
#endif

		goto start;
		}

	/* Unexpected handshake message (Client Hello, or protocol violation) */
	if ((s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) && 
		!s->in_handshake)
		{
		struct hm_header_st msg_hdr;
		
		/* this may just be a stale retransmit */
		dtls1_get_message_header(rr->data, &msg_hdr);
		if( rr->epoch != s->d1->r_epoch)
			{
			rr->length = 0;
			goto start;
			}

		/* If we are server, we may have a repeated FINISHED of the
		 * client here, then retransmit our CCS and FINISHED.
		 */
		if (msg_hdr.type == SSL3_MT_FINISHED)
			{
			if (dtls1_check_timeout_num(s) < 0)
				return -1;

			dtls1_retransmit_buffered_messages(s);
			rr->length = 0;
			goto start;
			}

		if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
			!(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
			{
#if 0 /* worked only because C operator preferences are not as expected (and
       * because this is not really needed for clients except for detecting
       * protocol violations): */
			s->state=SSL_ST_BEFORE|(s->server)
				?SSL_ST_ACCEPT
				:SSL_ST_CONNECT;
#else
			s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
#endif
			s->renegotiate=1;
			s->new_session=1;
			}
		i=s->handshake_func(s);
		if (i < 0) return(i);
		if (i == 0)
			{
			SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
			return(-1);
			}

		if (!(s->mode & SSL_MODE_AUTO_RETRY))
			{
			if (s->s3->rbuf.left == 0) /* no read-ahead left? */
				{
				BIO *bio;
				/* In the case where we try to read application data,
				 * but we trigger an SSL handshake, we return -1 with
				 * the retry option set.  Otherwise renegotiation may
				 * cause nasty problems in the blocking world */
				s->rwstate=SSL_READING;
				bio=SSL_get_rbio(s);
				BIO_clear_retry_flags(bio);
				BIO_set_retry_read(bio);
				return(-1);
				}
			}
		goto start;
		}

	switch (rr->type)
		{
	default:
#ifndef OPENSSL_NO_TLS
		/* TLS just ignores unknown message types */
		if (s->version == TLS1_VERSION)
			{
			rr->length = 0;
			goto start;
			}
#endif
		al=SSL_AD_UNEXPECTED_MESSAGE;
		SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
		goto f_err;
	case SSL3_RT_CHANGE_CIPHER_SPEC:
	case SSL3_RT_ALERT:
	case SSL3_RT_HANDSHAKE:
		/* we already handled all of these, with the possible exception
		 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
		 * should not happen when type != rr->type */
		al=SSL_AD_UNEXPECTED_MESSAGE;
		SSLerr(SSL_F_DTLS1_READ_BYTES,ERR_R_INTERNAL_ERROR);
		goto f_err;
	case SSL3_RT_APPLICATION_DATA:
		/* At this point, we were expecting handshake data,
		 * but have application data.  If the library was
		 * running inside ssl3_read() (i.e. in_read_app_data
		 * is set) and it makes sense to read application data
		 * at this point (session renegotiation not yet started),
		 * we will indulge it.
		 */
		if (s->s3->in_read_app_data &&
			(s->s3->total_renegotiations != 0) &&
			((
				(s->state & SSL_ST_CONNECT) &&
				(s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
				(s->state <= SSL3_ST_CR_SRVR_HELLO_A)
				) || (
					(s->state & SSL_ST_ACCEPT) &&
					(s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
					(s->state >= SSL3_ST_SR_CLNT_HELLO_A)
					)
				))
			{
			s->s3->in_read_app_data=2;
			return(-1);
			}
		else
			{
			al=SSL_AD_UNEXPECTED_MESSAGE;
			SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
			goto f_err;
			}
		}
	/* not reached */

f_err:
	ssl3_send_alert(s,SSL3_AL_FATAL,al);
err:
	return(-1);
	}

int
dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len)
	{
	int i;

#ifndef OPENSSL_NO_SCTP
		/* Check if we have to continue an interrupted handshake
		 * for reading belated app data with SCTP.
		 */
		if ((SSL_in_init(s) && !s->in_handshake) ||
		    (BIO_dgram_is_sctp(SSL_get_wbio(s)) &&
		     (s->state == DTLS1_SCTP_ST_SR_READ_SOCK || s->state == DTLS1_SCTP_ST_CR_READ_SOCK)))
#else
		if (SSL_in_init(s) && !s->in_handshake)
#endif
		{
		i=s->handshake_func(s);
		if (i < 0) return(i);
		if (i == 0)
			{
			SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
			return -1;
			}
		}

	if (len > SSL3_RT_MAX_PLAIN_LENGTH)
		{
			SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,SSL_R_DTLS_MESSAGE_TOO_BIG);
			return -1;
		}

	i = dtls1_write_bytes(s, type, buf_, len);
	return i;
	}


	/* this only happens when a client hello is received and a handshake 
	 * is started. */
static int
have_handshake_fragment(SSL *s, int type, unsigned char *buf, 
	int len, int peek)
	{
	
	if ((type == SSL3_RT_HANDSHAKE) && (s->d1->handshake_fragment_len > 0))
		/* (partially) satisfy request from storage */
		{
		unsigned char *src = s->d1->handshake_fragment;
		unsigned char *dst = buf;
		unsigned int k,n;
		
		/* peek == 0 */
		n = 0;
		while ((len > 0) && (s->d1->handshake_fragment_len > 0))
			{
			*dst++ = *src++;
			len--; s->d1->handshake_fragment_len--;
			n++;
			}
		/* move any remaining fragment bytes: */
		for (k = 0; k < s->d1->handshake_fragment_len; k++)
			s->d1->handshake_fragment[k] = *src++;
		return n;
		}
	
	return 0;
	}




/* Call this to write data in records of type 'type'
 * It will return <= 0 if not all data has been sent or non-blocking IO.
 */
int dtls1_write_bytes(SSL *s, int type, const void *buf, int len)
	{
	int i;

	OPENSSL_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH);
	s->rwstate=SSL_NOTHING;
	i=do_dtls1_write(s, type, buf, len, 0);
	return i;
	}

int do_dtls1_write(SSL *s, int type, const unsigned char *buf, unsigned int len, int create_empty_fragment)
	{
	unsigned char *p,*pseq;
	int i,mac_size,clear=0;
	int prefix_len = 0;
	SSL3_RECORD *wr;
	SSL3_BUFFER *wb;
	SSL_SESSION *sess;
	int bs;

	/* first check if there is a SSL3_BUFFER still being written
	 * out.  This will happen with non blocking IO */
	if (s->s3->wbuf.left != 0)
		{
		OPENSSL_assert(0); /* XDTLS:  want to see if we ever get here */
		return(ssl3_write_pending(s,type,buf,len));
		}

	/* If we have an alert to send, lets send it */
	if (s->s3->alert_dispatch)
		{
		i=s->method->ssl_dispatch_alert(s);
		if (i <= 0)
			return(i);
		/* if it went, fall through and send more stuff */
		}

	if (len == 0 && !create_empty_fragment)
		return 0;

	wr= &(s->s3->wrec);
	wb= &(s->s3->wbuf);
	sess=s->session;

	if (	(sess == NULL) ||
		(s->enc_write_ctx == NULL) ||
		(EVP_MD_CTX_md(s->write_hash) == NULL))
		clear=1;

	if (clear)
		mac_size=0;
	else
		{
		mac_size=EVP_MD_CTX_size(s->write_hash);
		if (mac_size < 0)
			goto err;
		}

	/* DTLS implements explicit IV, so no need for empty fragments */
#if 0
	/* 'create_empty_fragment' is true only when this function calls itself */
	if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done
	    && SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
		{
		/* countermeasure against known-IV weakness in CBC ciphersuites
		 * (see http://www.openssl.org/~bodo/tls-cbc.txt) 
		 */

		if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
			{
			/* recursive function call with 'create_empty_fragment' set;
			 * this prepares and buffers the data for an empty fragment
			 * (these 'prefix_len' bytes are sent out later
			 * together with the actual payload) */
			prefix_len = s->method->do_ssl_write(s, type, buf, 0, 1);
			if (prefix_len <= 0)
				goto err;

			if (s->s3->wbuf.len < (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE)
				{
				/* insufficient space */
				SSLerr(SSL_F_DO_DTLS1_WRITE, ERR_R_INTERNAL_ERROR);
				goto err;
				}
			}
		
		s->s3->empty_fragment_done = 1;
		}
#endif
	p = wb->buf + prefix_len;

	/* write the header */

	*(p++)=type&0xff;
	wr->type=type;

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

	/* field where we are to write out packet epoch, seq num and len */
	pseq=p; 
	p+=10;

	/* lets setup the record stuff. */

	/* Make space for the explicit IV in case of CBC.
	 * (this is a bit of a boundary violation, but what the heck).
	 */
	if ( s->enc_write_ctx && 
		(EVP_CIPHER_mode( s->enc_write_ctx->cipher ) & EVP_CIPH_CBC_MODE))
		bs = EVP_CIPHER_block_size(s->enc_write_ctx->cipher);
	else
		bs = 0;

	wr->data=p + bs;  /* make room for IV in case of CBC */
	wr->length=(int)len;
	wr->input=(unsigned char *)buf;

	/* we now 'read' from wr->input, wr->length bytes into
	 * wr->data */

	/* first we compress */
	if (s->compress != NULL)
		{
		if (!ssl3_do_compress(s))
			{
			SSLerr(SSL_F_DO_DTLS1_WRITE,SSL_R_COMPRESSION_FAILURE);
			goto err;
			}
		}
	else
		{
		memcpy(wr->data,wr->input,wr->length);
		wr->input=wr->data;
		}

	/* we should still have the output to wr->data and the input
	 * from wr->input.  Length should be wr->length.
	 * wr->data still points in the wb->buf */

	if (mac_size != 0)
		{
		if(s->method->ssl3_enc->mac(s,&(p[wr->length + bs]),1) < 0)
			goto err;
		wr->length+=mac_size;
		}

	/* this is true regardless of mac size */
	wr->input=p;
	wr->data=p;


	/* ssl3_enc can only have an error on read */
	if (bs)	/* bs != 0 in case of CBC */
		{
		RAND_pseudo_bytes(p,bs);
		/* master IV and last CBC residue stand for
		 * the rest of randomness */
		wr->length += bs;
		}

	s->method->ssl3_enc->enc(s,1);

	/* record length after mac and block padding */
/*	if (type == SSL3_RT_APPLICATION_DATA ||
	(type == SSL3_RT_ALERT && ! SSL_in_init(s))) */
	
	/* there's only one epoch between handshake and app data */
	
	s2n(s->d1->w_epoch, pseq);

	/* XDTLS: ?? */
/*	else
	s2n(s->d1->handshake_epoch, pseq); */

	memcpy(pseq, &(s->s3->write_sequence[2]), 6);
	pseq+=6;
	s2n(wr->length,pseq);

	/* we should now have
	 * wr->data pointing to the encrypted data, which is
	 * wr->length long */
	wr->type=type; /* not needed but helps for debugging */
	wr->length+=DTLS1_RT_HEADER_LENGTH;

#if 0  /* this is now done at the message layer */
	/* buffer the record, making it easy to handle retransmits */
	if ( type == SSL3_RT_HANDSHAKE || type == SSL3_RT_CHANGE_CIPHER_SPEC)
		dtls1_buffer_record(s, wr->data, wr->length, 
			*((PQ_64BIT *)&(s->s3->write_sequence[0])));
#endif

	ssl3_record_sequence_update(&(s->s3->write_sequence[0]));

	if (create_empty_fragment)
		{
		/* we are in a recursive call;
		 * just return the length, don't write out anything here
		 */
		return wr->length;
		}

	/* now let's set up wb */
	wb->left = prefix_len + wr->length;
	wb->offset = 0;

	/* memorize arguments so that ssl3_write_pending can detect bad write retries later */
	s->s3->wpend_tot=len;
	s->s3->wpend_buf=buf;
	s->s3->wpend_type=type;
	s->s3->wpend_ret=len;

	/* we now just need to write the buffer */
	return ssl3_write_pending(s,type,buf,len);
err:
	return -1;
	}



static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap)
	{
	int cmp;
	unsigned int shift;
	const unsigned char *seq = s->s3->read_sequence;

	cmp = satsub64be(seq,bitmap->max_seq_num);
	if (cmp > 0)
		{
		memcpy (s->s3->rrec.seq_num,seq,8);
		return 1; /* this record in new */
		}
	shift = -cmp;
	if (shift >= sizeof(bitmap->map)*8)
		return 0; /* stale, outside the window */
	else if (bitmap->map & (1UL<<shift))
		return 0; /* record previously received */

	memcpy (s->s3->rrec.seq_num,seq,8);
	return 1;
	}


static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap)
	{
	int cmp;
	unsigned int shift;
	const unsigned char *seq = s->s3->read_sequence;

	cmp = satsub64be(seq,bitmap->max_seq_num);
	if (cmp > 0)
		{
		shift = cmp;
		if (shift < sizeof(bitmap->map)*8)
			bitmap->map <<= shift, bitmap->map |= 1UL;
		else
			bitmap->map = 1UL;
		memcpy(bitmap->max_seq_num,seq,8);
		}
	else	{
		shift = -cmp;
		if (shift < sizeof(bitmap->map)*8)
			bitmap->map |= 1UL<<shift;
		}
	}


int dtls1_dispatch_alert(SSL *s)
	{
	int i,j;
	void (*cb)(const SSL *ssl,int type,int val)=NULL;
	unsigned char buf[DTLS1_AL_HEADER_LENGTH];
	unsigned char *ptr = &buf[0];

	s->s3->alert_dispatch=0;

	memset(buf, 0x00, sizeof(buf));
	*ptr++ = s->s3->send_alert[0];
	*ptr++ = s->s3->send_alert[1];

#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
	if (s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE)
		{	
		s2n(s->d1->handshake_read_seq, ptr);
#if 0
		if ( s->d1->r_msg_hdr.frag_off == 0)  /* waiting for a new msg */

		else
			s2n(s->d1->r_msg_hdr.seq, ptr); /* partial msg read */
#endif

#if 0
		fprintf(stderr, "s->d1->handshake_read_seq = %d, s->d1->r_msg_hdr.seq = %d\n",s->d1->handshake_read_seq,s->d1->r_msg_hdr.seq);
#endif
		l2n3(s->d1->r_msg_hdr.frag_off, ptr);
		}
#endif

	i = do_dtls1_write(s, SSL3_RT_ALERT, &buf[0], sizeof(buf), 0);
	if (i <= 0)
		{
		s->s3->alert_dispatch=1;
		/* fprintf( stderr, "not done with alert\n" ); */
		}
	else
		{
		if (s->s3->send_alert[0] == SSL3_AL_FATAL
#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
		    || s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
#endif
		    )
			(void)BIO_flush(s->wbio);

		if (s->msg_callback)
			s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 
				2, s, s->msg_callback_arg);

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

		if (cb != NULL)
			{
			j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
			cb(s,SSL_CB_WRITE_ALERT,j);
			}
		}
	return(i);
	}


static DTLS1_BITMAP *
dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr, unsigned int *is_next_epoch)
    {
    
    *is_next_epoch = 0;

    /* In current epoch, accept HM, CCS, DATA, & ALERT */
    if (rr->epoch == s->d1->r_epoch)
        return &s->d1->bitmap;

    /* Only HM and ALERT messages can be from the next epoch */
    else if (rr->epoch == (unsigned long)(s->d1->r_epoch + 1) &&
        (rr->type == SSL3_RT_HANDSHAKE ||
            rr->type == SSL3_RT_ALERT))
        {
        *is_next_epoch = 1;
        return &s->d1->next_bitmap;
        }

    return NULL;
    }

#if 0
static int
dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr, unsigned short *priority,
	unsigned long *offset)
	{

	/* alerts are passed up immediately */
	if ( rr->type == SSL3_RT_APPLICATION_DATA ||
		rr->type == SSL3_RT_ALERT)
		return 0;

	/* Only need to buffer if a handshake is underway.
	 * (this implies that Hello Request and Client Hello are passed up
	 * immediately) */
	if ( SSL_in_init(s))
		{
		unsigned char *data = rr->data;
		/* need to extract the HM/CCS sequence number here */
		if ( rr->type == SSL3_RT_HANDSHAKE ||
			rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
			{
			unsigned short seq_num;
			struct hm_header_st msg_hdr;
			struct ccs_header_st ccs_hdr;

			if ( rr->type == SSL3_RT_HANDSHAKE)
				{
				dtls1_get_message_header(data, &msg_hdr);
				seq_num = msg_hdr.seq;
				*offset = msg_hdr.frag_off;
				}
			else
				{
				dtls1_get_ccs_header(data, &ccs_hdr);
				seq_num = ccs_hdr.seq;
				*offset = 0;
				}
				
			/* this is either a record we're waiting for, or a
			 * retransmit of something we happened to previously 
			 * receive (higher layers will drop the repeat silently */
			if ( seq_num < s->d1->handshake_read_seq)
				return 0;
			if (rr->type == SSL3_RT_HANDSHAKE && 
				seq_num == s->d1->handshake_read_seq &&
				msg_hdr.frag_off < s->d1->r_msg_hdr.frag_off)
				return 0;
			else if ( seq_num == s->d1->handshake_read_seq &&
				(rr->type == SSL3_RT_CHANGE_CIPHER_SPEC ||
					msg_hdr.frag_off == s->d1->r_msg_hdr.frag_off))
				return 0;
			else
				{
				*priority = seq_num;
				return 1;
				}
			}
		else /* unknown record type */
			return 0;
		}

	return 0;
	}
#endif

void
dtls1_reset_seq_numbers(SSL *s, int rw)
	{
	unsigned char *seq;
	unsigned int seq_bytes = sizeof(s->s3->read_sequence);

	if ( rw & SSL3_CC_READ)
		{
		seq = s->s3->read_sequence;
		s->d1->r_epoch++;
		memcpy(&(s->d1->bitmap), &(s->d1->next_bitmap), sizeof(DTLS1_BITMAP));
		memset(&(s->d1->next_bitmap), 0x00, sizeof(DTLS1_BITMAP));
		}
	else
		{
		seq = s->s3->write_sequence;
		memcpy(s->d1->last_write_sequence, seq, sizeof(s->s3->write_sequence));
		s->d1->w_epoch++;
		}

	memset(seq, 0x00, seq_bytes);
	}