ssl/s2_enc.c

   1 /* ssl/s2_enc.c */
   2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
   3  * All rights reserved.
   4  *
   5  * This package is an SSL implementation written
   6  * by Eric Young (eay@cryptsoft.com).
   7  * The implementation was written so as to conform with Netscapes SSL.
   8  *
   9  * This library is free for commercial and non-commercial use as long as
  10  * the following conditions are aheared to.  The following conditions
  11  * apply to all code found in this distribution, be it the RC4, RSA,
  12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  13  * included with this distribution is covered by the same copyright terms
  14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
  15  *
  16  * Copyright remains Eric Young's, and as such any Copyright notices in
  17  * the code are not to be removed.
  18  * If this package is used in a product, Eric Young should be given attribution
  19  * as the author of the parts of the library used.
  20  * This can be in the form of a textual message at program startup or
  21  * in documentation (online or textual) provided with the package.
  22  *
  23  * Redistribution and use in source and binary forms, with or without
  24  * modification, are permitted provided that the following conditions
  25  * are met:
  26  * 1. Redistributions of source code must retain the copyright
  27  *    notice, this list of conditions and the following disclaimer.
  28  * 2. Redistributions in binary form must reproduce the above copyright
  29  *    notice, this list of conditions and the following disclaimer in the
  30  *    documentation and/or other materials provided with the distribution.
  31  * 3. All advertising materials mentioning features or use of this software
  32  *    must display the following acknowledgement:
  33  *    "This product includes cryptographic software written by
  34  *     Eric Young (eay@cryptsoft.com)"
  35  *    The word 'cryptographic' can be left out if the rouines from the library
  36  *    being used are not cryptographic related :-).
  37  * 4. If you include any Windows specific code (or a derivative thereof) from
  38  *    the apps directory (application code) you must include an acknowledgement:
  39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
  40  *
  41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  51  * SUCH DAMAGE.
  52  *
  53  * The licence and distribution terms for any publically available version or
  54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
  55  * copied and put under another distribution licence
  56  * [including the GNU Public Licence.]
  57  */
  58
  59 #include "ssl_locl.h"
  60 #ifndef NO_SSL2
  61 #include <stdio.h>
  62
  63 int ssl2_enc_init(SSL *s, int client)
  64         {
  65         /* Max number of bytes needed */
  66         EVP_CIPHER_CTX *rs,*ws;
  67         const EVP_CIPHER *c;
  68         const EVP_MD *md;
  69         int num;
  70
  71         if (!ssl_cipher_get_evp(s->session,&c,&md,NULL))
  72                 {
  73                 ssl2_return_error(s,SSL2_PE_NO_CIPHER);
  74                 SSLerr(SSL_F_SSL2_ENC_INIT,SSL_R_PROBLEMS_MAPPING_CIPHER_FUNCTIONS);
  75                 return(0);
  76                 }
  77
  78         s->read_hash=md;
  79         s->write_hash=md;
  80
  81         if ((s->enc_read_ctx == NULL) &&
  82                 ((s->enc_read_ctx=(EVP_CIPHER_CTX *)
  83                 OPENSSL_malloc(sizeof(EVP_CIPHER_CTX))) == NULL))
  84                 goto err;
  85         if ((s->enc_write_ctx == NULL) &&
  86                 ((s->enc_write_ctx=(EVP_CIPHER_CTX *)
  87                 OPENSSL_malloc(sizeof(EVP_CIPHER_CTX))) == NULL))
  88                 goto err;
  89
  90         rs= s->enc_read_ctx;
  91         ws= s->enc_write_ctx;
  92
  93         EVP_CIPHER_CTX_init(rs);
  94         EVP_CIPHER_CTX_init(ws);
  95
  96         num=c->key_len;
  97         s->s2->key_material_length=num*2;
  98
  99         ssl2_generate_key_material(s);
 100
 101         EVP_EncryptInit(ws,c,&(s->s2->key_material[(client)?num:0]),
 102                 s->session->key_arg);
 103         EVP_DecryptInit(rs,c,&(s->s2->key_material[(client)?0:num]),
 104                 s->session->key_arg);
 105         s->s2->read_key=  &(s->s2->key_material[(client)?0:num]);
 106         s->s2->write_key= &(s->s2->key_material[(client)?num:0]);
 107         return(1);
 108 err:
 109         SSLerr(SSL_F_SSL2_ENC_INIT,ERR_R_MALLOC_FAILURE);
 110         return(0);
 111         }
 112
 113 /* read/writes from s->s2->mac_data using length for encrypt and
 114  * decrypt.  It sets the s->s2->padding, s->[rw]length and
 115  * s->s2->pad_data ptr if we are encrypting */
 116 void ssl2_enc(SSL *s, int send)
 117         {
 118         EVP_CIPHER_CTX *ds;
 119         unsigned long l;
 120         int bs;
 121
 122         if (send)
 123                 {
 124                 ds=s->enc_write_ctx;
 125                 l=s->s2->wlength;
 126                 }
 127         else
 128                 {
 129                 ds=s->enc_read_ctx;
 130                 l=s->s2->rlength;
 131                 }
 132
 133         /* check for NULL cipher */
 134         if (ds == NULL) return;
 135
 136
 137         bs=ds->cipher->block_size;
 138         /* This should be using (bs-1) and bs instead of 7 and 8, but
 139          * what the hell. */
 140         if (bs == 8)
 141                 l=(l+7)/8*8;
 142
 143         EVP_Cipher(ds,s->s2->mac_data,s->s2->mac_data,l);
 144         }
 145
 146 void ssl2_mac(SSL *s, unsigned char *md, int send)
 147         {
 148         EVP_MD_CTX c;
 149         unsigned char sequence[4],*p,*sec,*act;
 150         unsigned long seq;
 151         unsigned int len;
 152
 153         if (send)
 154                 {
 155                 seq=s->s2->write_sequence;
 156                 sec=s->s2->write_key;
 157                 len=s->s2->wact_data_length;
 158                 act=s->s2->wact_data;
 159                 }
 160         else
 161                 {
 162                 seq=s->s2->read_sequence;
 163                 sec=s->s2->read_key;
 164                 len=s->s2->ract_data_length;
 165                 act=s->s2->ract_data;
 166                 }
 167
 168         p= &(sequence[0]);
 169         l2n(seq,p);
 170
 171         /* There has to be a MAC algorithm. */
 172         EVP_DigestInit(&c,s->read_hash);
 173         EVP_DigestUpdate(&c,sec,
 174                 EVP_CIPHER_CTX_key_length(s->enc_read_ctx));
 175         EVP_DigestUpdate(&c,act,len);
 176         /* the above line also does the pad data */
 177         EVP_DigestUpdate(&c,sequence,4);
 178         EVP_DigestFinal(&c,md,NULL);
 179         /* some would say I should zero the md context */
 180         }
 181 #else /* !NO_SSL2 */
 182
 183 # if PEDANTIC
 184 static void *dummy=&dummy;
 185 # endif
 186
 187 #endif