crypto/openssl-0.9/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 OPENSSL_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
  86         /* make sure it's intialized in case the malloc for enc_write_ctx fails
  87          * and we exit with an error */
  88         rs= s->enc_read_ctx;
  89         EVP_CIPHER_CTX_init(rs);
  90
  91         if ((s->enc_write_ctx == NULL) &&
  92                 ((s->enc_write_ctx=(EVP_CIPHER_CTX *)
  93                 OPENSSL_malloc(sizeof(EVP_CIPHER_CTX))) == NULL))
  94                 goto err;
  95
  96         ws= s->enc_write_ctx;
  97         EVP_CIPHER_CTX_init(ws);
  98
  99         num=c->key_len;
 100         s->s2->key_material_length=num*2;
 101         OPENSSL_assert(s->s2->key_material_length <= sizeof s->s2->key_material);
 102
 103         if (ssl2_generate_key_material(s) <= 0)
 104                 return 0;
 105
 106         OPENSSL_assert(c->iv_len <= (int)sizeof(s->session->key_arg));
 107         EVP_EncryptInit_ex(ws,c,NULL,&(s->s2->key_material[(client)?num:0]),
 108                 s->session->key_arg);
 109         EVP_DecryptInit_ex(rs,c,NULL,&(s->s2->key_material[(client)?0:num]),
 110                 s->session->key_arg);
 111         s->s2->read_key=  &(s->s2->key_material[(client)?0:num]);
 112         s->s2->write_key= &(s->s2->key_material[(client)?num:0]);
 113         return(1);
 114 err:
 115         SSLerr(SSL_F_SSL2_ENC_INIT,ERR_R_MALLOC_FAILURE);
 116         return(0);
 117         }
 118
 119 /* read/writes from s->s2->mac_data using length for encrypt and
 120  * decrypt.  It sets s->s2->padding and s->[rw]length
 121  * if we are encrypting */
 122 void ssl2_enc(SSL *s, int send)
 123         {
 124         EVP_CIPHER_CTX *ds;
 125         unsigned long l;
 126         int bs;
 127
 128         if (send)
 129                 {
 130                 ds=s->enc_write_ctx;
 131                 l=s->s2->wlength;
 132                 }
 133         else
 134                 {
 135                 ds=s->enc_read_ctx;
 136                 l=s->s2->rlength;
 137                 }
 138
 139         /* check for NULL cipher */
 140         if (ds == NULL) return;
 141
 142
 143         bs=ds->cipher->block_size;
 144         /* This should be using (bs-1) and bs instead of 7 and 8, but
 145          * what the hell. */
 146         if (bs == 8)
 147                 l=(l+7)/8*8;
 148
 149         EVP_Cipher(ds,s->s2->mac_data,s->s2->mac_data,l);
 150         }
 151
 152 void ssl2_mac(SSL *s, unsigned char *md, int send)
 153         {
 154         EVP_MD_CTX c;
 155         unsigned char sequence[4],*p,*sec,*act;
 156         unsigned long seq;
 157         unsigned int len;
 158
 159         if (send)
 160                 {
 161                 seq=s->s2->write_sequence;
 162                 sec=s->s2->write_key;
 163                 len=s->s2->wact_data_length;
 164                 act=s->s2->wact_data;
 165                 }
 166         else
 167                 {
 168                 seq=s->s2->read_sequence;
 169                 sec=s->s2->read_key;
 170                 len=s->s2->ract_data_length;
 171                 act=s->s2->ract_data;
 172                 }
 173
 174         p= &(sequence[0]);
 175         l2n(seq,p);
 176
 177         /* There has to be a MAC algorithm. */
 178         EVP_MD_CTX_init(&c);
 179         EVP_DigestInit_ex(&c, s->read_hash, NULL);
 180         EVP_DigestUpdate(&c,sec,
 181                 EVP_CIPHER_CTX_key_length(s->enc_read_ctx));
 182         EVP_DigestUpdate(&c,act,len);
 183         /* the above line also does the pad data */
 184         EVP_DigestUpdate(&c,sequence,4);
 185         EVP_DigestFinal_ex(&c,md,NULL);
 186         EVP_MD_CTX_cleanup(&c);
 187         }
 188 #else /* !OPENSSL_NO_SSL2 */
 189
 190 # if PEDANTIC
 191 static void *dummy=&dummy;
 192 # endif
 193
 194 #endif