/* ssl/s2_pkt.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) 1998-2001 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).

 *

 */

#include "ssl_locl.h"

#ifndef OPENSSL_NO_SSL2

#include <stdio.h>

#include <errno.h>

#define USE_SOCKETS

static int read_n(SSL *s,unsigned int n,unsigned int max,unsigned int extend);

static int do_ssl_write(SSL *s, const unsigned char *buf, unsigned int len);

static int write_pending(SSL *s, const unsigned char *buf, unsigned int len);

static int ssl_mt_error(int n);

/* SSL 2.0 imlementation for SSL_read/SSL_peek -

 * This routine will return 0 to len bytes, decrypted etc if required.

 */

static int ssl2_read_internal(SSL *s, void *buf, int len, int peek)

	{

	int n;

	unsigned char mac[MAX_MAC_SIZE];

	unsigned char *p;

	int i;

	unsigned int mac_size;

 ssl2_read_again:

	if (SSL_in_init(s) && !s->in_handshake)

		{

		n=s->handshake_func(s);

		if (n < 0) return(n);

		if (n == 0)

			{

			SSLerr(SSL_F_SSL2_READ_INTERNAL,SSL_R_SSL_HANDSHAKE_FAILURE);

			return(-1);

			}

		}

	clear_sys_error();

	s->rwstate=SSL_NOTHING;

	if (len <= 0) return(len);

	if (s->s2->ract_data_length != 0) /* read from buffer */

		{

		if (len > s->s2->ract_data_length)

			n=s->s2->ract_data_length;

		else

			n=len;

		memcpy(buf,s->s2->ract_data,(unsigned int)n);

		if (!peek)

			{

			s->s2->ract_data_length-=n;

			s->s2->ract_data+=n;

			if (s->s2->ract_data_length == 0)

				s->rstate=SSL_ST_READ_HEADER;

			}

		return(n);

		}

	/* s->s2->ract_data_length == 0

	 * 

	 * Fill the buffer, then goto ssl2_read_again.

	 */

	if (s->rstate == SSL_ST_READ_HEADER)

		{

		if (s->first_packet)

			{

			n=read_n(s,5,SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER+2,0);

			if (n <= 0) return(n); /* error or non-blocking */

			s->first_packet=0;

			p=s->packet;

			if (!((p[0] & 0x80) && (

				(p[2] == SSL2_MT_CLIENT_HELLO) ||

				(p[2] == SSL2_MT_SERVER_HELLO))))

				{

				SSLerr(SSL_F_SSL2_READ_INTERNAL,SSL_R_NON_SSLV2_INITIAL_PACKET);

				return(-1);

				}

			}

		else

			{

			n=read_n(s,2,SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER+2,0);

			if (n <= 0) return(n); /* error or non-blocking */

			}

		/* part read stuff */

		s->rstate=SSL_ST_READ_BODY;

		p=s->packet;

		/* Do header */

		/*s->s2->padding=0;*/

		s->s2->escape=0;

		s->s2->rlength=(((unsigned int)p[0])<<8)|((unsigned int)p[1]);

		if ((p[0] & TWO_BYTE_BIT))		/* Two byte header? */

			{

			s->s2->three_byte_header=0;

			s->s2->rlength&=TWO_BYTE_MASK;	

			}

		else

			{

			s->s2->three_byte_header=1;

			s->s2->rlength&=THREE_BYTE_MASK;

			/* security >s2->escape */

			s->s2->escape=((p[0] & SEC_ESC_BIT))?1:0;

			}

		}

	if (s->rstate == SSL_ST_READ_BODY)

		{

		n=s->s2->rlength+2+s->s2->three_byte_header;

		if (n > (int)s->packet_length)

			{

			n-=s->packet_length;

			i=read_n(s,(unsigned int)n,(unsigned int)n,1);

			if (i <= 0) return(i); /* ERROR */

			}

		p= &(s->packet[2]);

		s->rstate=SSL_ST_READ_HEADER;

		if (s->s2->three_byte_header)

			s->s2->padding= *(p++);

		else	s->s2->padding=0;

		/* Data portion */

		if (s->s2->clear_text)

			{

			mac_size = 0;

			s->s2->mac_data=p;

			s->s2->ract_data=p;

			if (s->s2->padding)

				{

				SSLerr(SSL_F_SSL2_READ_INTERNAL,SSL_R_ILLEGAL_PADDING);

				return(-1);

				}

			}

		else

			{

			mac_size=EVP_MD_size(s->read_hash);

			OPENSSL_assert(mac_size <= MAX_MAC_SIZE);

			s->s2->mac_data=p;

			s->s2->ract_data= &p[mac_size];

			if (s->s2->padding + mac_size > s->s2->rlength)

				{

				SSLerr(SSL_F_SSL2_READ_INTERNAL,SSL_R_ILLEGAL_PADDING);

				return(-1);

				}

			}

		s->s2->ract_data_length=s->s2->rlength;

		/* added a check for length > max_size in case

		 * encryption was not turned on yet due to an error */

		if ((!s->s2->clear_text) &&

			(s->s2->rlength >= mac_size))

			{

			ssl2_enc(s,0);

			s->s2->ract_data_length-=mac_size;

			ssl2_mac(s,mac,0);

			s->s2->ract_data_length-=s->s2->padding;

			if (	(memcmp(mac,s->s2->mac_data,

				(unsigned int)mac_size) != 0) ||

				(s->s2->rlength%EVP_CIPHER_CTX_block_size(s->enc_read_ctx) != 0))

				{

				SSLerr(SSL_F_SSL2_READ_INTERNAL,SSL_R_BAD_MAC_DECODE);

				return(-1);

				}

			}

		INC32(s->s2->read_sequence); /* expect next number */

		/* s->s2->ract_data is now available for processing */

		/* Possibly the packet that we just read had 0 actual data bytes.

		 * (SSLeay/OpenSSL itself never sends such packets; see ssl2_write.)

		 * In this case, returning 0 would be interpreted by the caller

		 * as indicating EOF, so it's not a good idea.  Instead, we just

		 * continue reading; thus ssl2_read_internal may have to process

		 * multiple packets before it can return.

		 *

		 * [Note that using select() for blocking sockets *never* guarantees

		 * that the next SSL_read will not block -- the available

		 * data may contain incomplete packets, and except for SSL 2,

		 * renegotiation can confuse things even more.] */

		goto ssl2_read_again; /* This should really be

		                       * "return ssl2_read(s,buf,len)",

		                       * but that would allow for

		                       * denial-of-service attacks if a

		                       * C compiler is used that does not

		                       * recognize end-recursion. */

		}

	else

		{

		SSLerr(SSL_F_SSL2_READ_INTERNAL,SSL_R_BAD_STATE);

			return(-1);

		}

	}

int ssl2_read(SSL *s, void *buf, int len)

	{

	return ssl2_read_internal(s, buf, len, 0);

	}

int ssl2_peek(SSL *s, void *buf, int len)

	{

	return ssl2_read_internal(s, buf, len, 1);

	}

static int read_n(SSL *s, unsigned int n, unsigned int max,

	     unsigned int extend)

	{

	int i,off,newb;

	/* if there is stuff still in the buffer from a previous read,

	 * and there is more than we want, take some. */

	if (s->s2->rbuf_left >= (int)n)

		{

		if (extend)

			s->packet_length+=n;

		else

			{

			s->packet= &(s->s2->rbuf[s->s2->rbuf_offs]);

			s->packet_length=n;

			}

		s->s2->rbuf_left-=n;

		s->s2->rbuf_offs+=n;

		return(n);

		}

	if (!s->read_ahead) max=n;

	if (max > (unsigned int)(SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER+2))

		max=SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER+2;

	/* Else we want more than we have.

	 * First, if there is some left or we want to extend */

	off=0;

	if ((s->s2->rbuf_left != 0) || ((s->packet_length != 0) && extend))

		{

		newb=s->s2->rbuf_left;

		if (extend)

			{

			off=s->packet_length;

			if (s->packet != s->s2->rbuf)

				memcpy(s->s2->rbuf,s->packet,

					(unsigned int)newb+off);

			}

		else if (s->s2->rbuf_offs != 0)

			{

			memcpy(s->s2->rbuf,&(s->s2->rbuf[s->s2->rbuf_offs]),

				(unsigned int)newb);

			s->s2->rbuf_offs=0;

			}

		s->s2->rbuf_left=0;

		}

	else

		newb=0;

	/* off is the offset to start writing too.

	 * r->s2->rbuf_offs is the 'unread data', now 0. 

	 * newb is the number of new bytes so far

	 */

	s->packet=s->s2->rbuf;

	while (newb < (int)n)

		{

		clear_sys_error();

		if (s->rbio != NULL)

			{

			s->rwstate=SSL_READING;

			i=BIO_read(s->rbio,(char *)&(s->s2->rbuf[off+newb]),

				max-newb);

			}

		else

			{

			SSLerr(SSL_F_READ_N,SSL_R_READ_BIO_NOT_SET);

			i= -1;

			}

#ifdef PKT_DEBUG

		if (s->debug & 0x01) sleep(1);

#endif

		if (i <= 0)

			{

			s->s2->rbuf_left+=newb;

			return(i);

			}

		newb+=i;

		}

	/* record unread data */

	if (newb > (int)n)

		{

		s->s2->rbuf_offs=n+off;

		s->s2->rbuf_left=newb-n;

		}

	else

		{

		s->s2->rbuf_offs=0;

		s->s2->rbuf_left=0;

		}

	if (extend)

		s->packet_length+=n;

	else

		s->packet_length=n;

	s->rwstate=SSL_NOTHING;

	return(n);

	}

int ssl2_write(SSL *s, const void *_buf, int len)

	{

	const unsigned char *buf=_buf;

	unsigned int n,tot;

	int i;

	if (SSL_in_init(s) && !s->in_handshake)

		{

		i=s->handshake_func(s);

		if (i < 0) return(i);

		if (i == 0)

			{

			SSLerr(SSL_F_SSL2_WRITE,SSL_R_SSL_HANDSHAKE_FAILURE);

			return(-1);

			}

		}

	if (s->error)

		{

		ssl2_write_error(s);

		if (s->error)

			return(-1);

		}

	clear_sys_error();

	s->rwstate=SSL_NOTHING;

	if (len <= 0) return(len);

	tot=s->s2->wnum;

	s->s2->wnum=0;

	n=(len-tot);

	for (;;)

		{

		i=do_ssl_write(s,&(buf[tot]),n);

		if (i <= 0)

			{

			s->s2->wnum=tot;

			return(i);

			}

		if ((i == (int)n) ||

			(s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE))

			{

			return(tot+i);

			}

		n-=i;

		tot+=i;

		}

	}

static int write_pending(SSL *s, const unsigned char *buf, unsigned int len)

	{

	int i;

	/* s->s2->wpend_len != 0 MUST be true. */

	/* check that they have given us the same buffer to

	 * write */

	if ((s->s2->wpend_tot > (int)len) ||

		((s->s2->wpend_buf != buf) &&

		 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER)))

		{

		SSLerr(SSL_F_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);

		return(-1);

		}

	for (;;)

		{

		clear_sys_error();

		if (s->wbio != NULL)

			{

			s->rwstate=SSL_WRITING;

			i=BIO_write(s->wbio,

				(char *)&(s->s2->write_ptr[s->s2->wpend_off]),

				(unsigned int)s->s2->wpend_len);

			}

		else

			{

			SSLerr(SSL_F_WRITE_PENDING,SSL_R_WRITE_BIO_NOT_SET);

			i= -1;

			}

#ifdef PKT_DEBUG

		if (s->debug & 0x01) sleep(1);

#endif

		if (i == s->s2->wpend_len)

			{

			s->s2->wpend_len=0;

			s->rwstate=SSL_NOTHING;

			return(s->s2->wpend_ret);

			}

		else if (i <= 0)

			return(i);

		s->s2->wpend_off+=i;

		s->s2->wpend_len-=i;

		}

	}

static int do_ssl_write(SSL *s, const unsigned char *buf, unsigned int len)

	{

	unsigned int j,k,olen,p,mac_size,bs;

	register unsigned char *pp;

	olen=len;

	/* first check if there is data from an encryption waiting to

	 * be sent - it must be sent because the other end is waiting.

	 * This will happen with non-blocking IO.  We print it and then

	 * return.

	 */

	if (s->s2->wpend_len != 0) return(write_pending(s,buf,len));

	/* set mac_size to mac size */