text: /* ssl/s2_enc.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.]
   */
  
  #include "ssl_locl.h"
  #ifndef NO_SSL2
  #include <stdio.h>
  
  int ssl2_enc_init(SSL *s, int client)
  	{
  	/* Max number of bytes needed */
  	EVP_CIPHER_CTX *rs,*ws;
  	const EVP_CIPHER *c;
  	const EVP_MD *md;
  	int num;
  
  	if (!ssl_cipher_get_evp(s->session,&c,&md,NULL))
  		{
  		ssl2_return_error(s,SSL2_PE_NO_CIPHER);
  		SSLerr(SSL_F_SSL2_ENC_INIT,SSL_R_PROBLEMS_MAPPING_CIPHER_FUNCTIONS);
  		return(0);
  		}
  
  	s->read_hash=md;
  	s->write_hash=md;
  
  	if ((s->enc_read_ctx == NULL) &&
  		((s->enc_read_ctx=(EVP_CIPHER_CTX *)
  		OPENSSL_malloc(sizeof(EVP_CIPHER_CTX))) == NULL))
  		goto err;
  	if ((s->enc_write_ctx == NULL) &&
  		((s->enc_write_ctx=(EVP_CIPHER_CTX *)
  		OPENSSL_malloc(sizeof(EVP_CIPHER_CTX))) == NULL))
  		goto err;
  
  	rs= s->enc_read_ctx;
  	ws= s->enc_write_ctx;
  
  	EVP_CIPHER_CTX_init(rs);
  	EVP_CIPHER_CTX_init(ws);
  
  	num=c->key_len;
  	s->s2->key_material_length=num*2;
  
  	ssl2_generate_key_material(s);
  
  	EVP_EncryptInit(ws,c,&(s->s2->key_material[(client)?num:0]),
  		s->session->key_arg);
  	EVP_DecryptInit(rs,c,&(s->s2->key_material[(client)?0:num]),
  		s->session->key_arg);
  	s->s2->read_key=  &(s->s2->key_material[(client)?0:num]);
  	s->s2->write_key= &(s->s2->key_material[(client)?num:0]);
  	return(1);
  err:
  	SSLerr(SSL_F_SSL2_ENC_INIT,ERR_R_MALLOC_FAILURE);
  	return(0);
  	}
  
  /* read/writes from s->s2->mac_data using length for encrypt and 
   * decrypt.  It sets the s->s2->padding, s->[rw]length and
   * s->s2->pad_data ptr if we are encrypting */
  void ssl2_enc(SSL *s, int send)
  	{
  	EVP_CIPHER_CTX *ds;
  	unsigned long l;
  	int bs;
  
  	if (send)
  		{
  		ds=s->enc_write_ctx;
  		l=s->s2->wlength;
  		}
  	else
  		{
  		ds=s->enc_read_ctx;
  		l=s->s2->rlength;
  		}
  
  	/* check for NULL cipher */
  	if (ds == NULL) return;
  
  
  	bs=ds->cipher->block_size;
  	/* This should be using (bs-1) and bs instead of 7 and 8, but
  	 * what the hell. */
  	if (bs == 8)
  		l=(l+7)/8*8;
  
  	EVP_Cipher(ds,s->s2->mac_data,s->s2->mac_data,l);
  	}
  
  void ssl2_mac(SSL *s, unsigned char *md, int send)
  	{
  	EVP_MD_CTX c;
  	unsigned char sequence[4],*p,*sec,*act;
  	unsigned long seq;
  	unsigned int len;
  
  	if (send)
  		{
  		seq=s->s2->write_sequence;
  		sec=s->s2->write_key;
  		len=s->s2->wact_data_length;
  		act=s->s2->wact_data;
  		}
  	else
  		{
  		seq=s->s2->read_sequence;
  		sec=s->s2->read_key;
  		len=s->s2->ract_data_length;
  		act=s->s2->ract_data;
  		}
  
  	p= &(sequence[0]);
  	l2n(seq,p);
  
  	/* There has to be a MAC algorithm. */
  	EVP_DigestInit(&c,s->read_hash);
  	EVP_DigestUpdate(&c,sec,
  		EVP_CIPHER_CTX_key_length(s->enc_read_ctx));
  	EVP_DigestUpdate(&c,act,len); 
  	/* the above line also does the pad data */
  	EVP_DigestUpdate(&c,sequence,4); 
  	EVP_DigestFinal(&c,md,NULL);
  	/* some would say I should zero the md context */
  	}
  #else /* !NO_SSL2 */
  
  # if PEDANTIC
  static void *dummy=&dummy;
  # endif
  
  #endif
  