crypto/external/bsd/openssl/dist/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, NULL, NULL)) {
  72         ssl2_return_error(s, SSL2_PE_NO_CIPHER);
  73         SSLerr(SSL_F_SSL2_ENC_INIT, SSL_R_PROBLEMS_MAPPING_CIPHER_FUNCTIONS);
  74         return (0);
  75     }
  76     ssl_replace_hash(&s->read_hash, md);
  77     ssl_replace_hash(&s->write_hash, md);
  78
  79     if ((s->enc_read_ctx == NULL) && ((s->enc_read_ctx = (EVP_CIPHER_CTX *)
  80                                        OPENSSL_malloc(sizeof(EVP_CIPHER_CTX)))
  81                                       == NULL))
  82         goto err;
  83
  84     /*
  85      * make sure it's intialized in case the malloc for enc_write_ctx fails
  86      * and we exit with an error
  87      */
  88     rs = s->enc_read_ctx;
  89     EVP_CIPHER_CTX_init(rs);
  90
  91     if ((s->enc_write_ctx == NULL) && ((s->enc_write_ctx = (EVP_CIPHER_CTX *)
  92                                         OPENSSL_malloc(sizeof
  93                                                        (EVP_CIPHER_CTX))) ==
  94                                        NULL))
  95         goto err;
  96
  97     ws = s->enc_write_ctx;
  98     EVP_CIPHER_CTX_init(ws);
  99
 100     num = c->key_len;
 101     s->s2->key_material_length = num * 2;
 102     OPENSSL_assert(s->s2->key_material_length <= sizeof s->s2->key_material);
 103
 104     if (ssl2_generate_key_material(s) <= 0)
 105         return 0;
 106
 107     OPENSSL_assert(c->iv_len <= (int)sizeof(s->session->key_arg));
 108     EVP_EncryptInit_ex(ws, c, NULL,
 109                        &(s->s2->key_material[(client) ? num : 0]),
 110                        s->session->key_arg);
 111     EVP_DecryptInit_ex(rs, c, NULL,
 112                        &(s->s2->key_material[(client) ? 0 : num]),
 113                        s->session->key_arg);
 114     s->s2->read_key = &(s->s2->key_material[(client) ? 0 : num]);
 115     s->s2->write_key = &(s->s2->key_material[(client) ? num : 0]);
 116     return (1);
 117  err:
 118     SSLerr(SSL_F_SSL2_ENC_INIT, ERR_R_MALLOC_FAILURE);
 119     return (0);
 120 }
 121
 122 /*
 123  * read/writes from s->s2->mac_data using length for encrypt and decrypt.
 124  * It sets s->s2->padding and s->[rw]length if we are encrypting Returns 0 on
 125  * error and 1 on success
 126  */
 127 int ssl2_enc(SSL *s, int send)
 128 {
 129     EVP_CIPHER_CTX *ds;
 130     unsigned long l;
 131     int bs;
 132
 133     if (send) {
 134         ds = s->enc_write_ctx;
 135         l = s->s2->wlength;
 136     } else {
 137         ds = s->enc_read_ctx;
 138         l = s->s2->rlength;
 139     }
 140
 141     /* check for NULL cipher */
 142     if (ds == NULL)
 143         return 1;
 144
 145     bs = ds->cipher->block_size;
 146     /*
 147      * This should be using (bs-1) and bs instead of 7 and 8, but what the
 148      * hell.
 149      */
 150     if (bs == 8)
 151         l = (l + 7) / 8 * 8;
 152
 153     if (EVP_Cipher(ds, s->s2->mac_data, s->s2->mac_data, l) < 1)
 154         return 0;
 155
 156     return 1;
 157 }
 158
 159 void ssl2_mac(SSL *s, unsigned char *md, int send)
 160 {
 161     EVP_MD_CTX c;
 162     unsigned char sequence[4], *p, *sec, *act;
 163     unsigned long seq;
 164     unsigned int len;
 165
 166     if (send) {
 167         seq = s->s2->write_sequence;
 168         sec = s->s2->write_key;
 169         len = s->s2->wact_data_length;
 170         act = s->s2->wact_data;
 171     } else {
 172         seq = s->s2->read_sequence;
 173         sec = s->s2->read_key;
 174         len = s->s2->ract_data_length;
 175         act = s->s2->ract_data;
 176     }
 177
 178     p = &(sequence[0]);
 179     l2n(seq, p);
 180
 181     /* There has to be a MAC algorithm. */
 182     EVP_MD_CTX_init(&c);
 183     EVP_MD_CTX_copy(&c, s->read_hash);
 184     EVP_DigestUpdate(&c, sec, EVP_CIPHER_CTX_key_length(s->enc_read_ctx));
 185     EVP_DigestUpdate(&c, act, len);
 186     /* the above line also does the pad data */
 187     EVP_DigestUpdate(&c, sequence, 4);
 188     EVP_DigestFinal_ex(&c, md, NULL);
 189     EVP_MD_CTX_cleanup(&c);
 190 }
 191 #else                           /* !OPENSSL_NO_SSL2 */
 192
 193 # if PEDANTIC
 194 static void *dummy = &dummy;
 195 # endif
 196
 197 #endif