crypto/openssl/ssl/d1_enc.c

   1 /* ssl/d1_enc.c */
   2 /*
   3  * DTLS implementation written by Nagendra Modadugu
   4  * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
   5  */
   6 /* ====================================================================
   7  * Copyright (c) 1998-2005 The OpenSSL Project.  All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  *
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  *
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in
  18  *    the documentation and/or other materials provided with the
  19  *    distribution.
  20  *
  21  * 3. All advertising materials mentioning features or use of this
  22  *    software must display the following acknowledgment:
  23  *    "This product includes software developed by the OpenSSL Project
  24  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
  25  *
  26  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  27  *    endorse or promote products derived from this software without
  28  *    prior written permission. For written permission, please contact
  29  *    openssl-core@openssl.org.
  30  *
  31  * 5. Products derived from this software may not be called "OpenSSL"
  32  *    nor may "OpenSSL" appear in their names without prior written
  33  *    permission of the OpenSSL Project.
  34  *
  35  * 6. Redistributions of any form whatsoever must retain the following
  36  *    acknowledgment:
  37  *    "This product includes software developed by the OpenSSL Project
  38  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
  39  *
  40  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  41  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  43  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  44  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  45  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  46  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  47  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  49  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  50  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  51  * OF THE POSSIBILITY OF SUCH DAMAGE.
  52  * ====================================================================
  53  *
  54  * This product includes cryptographic software written by Eric Young
  55  * (eay@cryptsoft.com).  This product includes software written by Tim
  56  * Hudson (tjh@cryptsoft.com).
  57  *
  58  */
  59 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  60  * All rights reserved.
  61  *
  62  * This package is an SSL implementation written
  63  * by Eric Young (eay@cryptsoft.com).
  64  * The implementation was written so as to conform with Netscapes SSL.
  65  *
  66  * This library is free for commercial and non-commercial use as long as
  67  * the following conditions are aheared to.  The following conditions
  68  * apply to all code found in this distribution, be it the RC4, RSA,
  69  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  70  * included with this distribution is covered by the same copyright terms
  71  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
  72  *
  73  * Copyright remains Eric Young's, and as such any Copyright notices in
  74  * the code are not to be removed.
  75  * If this package is used in a product, Eric Young should be given attribution
  76  * as the author of the parts of the library used.
  77  * This can be in the form of a textual message at program startup or
  78  * in documentation (online or textual) provided with the package.
  79  *
  80  * Redistribution and use in source and binary forms, with or without
  81  * modification, are permitted provided that the following conditions
  82  * are met:
  83  * 1. Redistributions of source code must retain the copyright
  84  *    notice, this list of conditions and the following disclaimer.
  85  * 2. Redistributions in binary form must reproduce the above copyright
  86  *    notice, this list of conditions and the following disclaimer in the
  87  *    documentation and/or other materials provided with the distribution.
  88  * 3. All advertising materials mentioning features or use of this software
  89  *    must display the following acknowledgement:
  90  *    "This product includes cryptographic software written by
  91  *     Eric Young (eay@cryptsoft.com)"
  92  *    The word 'cryptographic' can be left out if the rouines from the library
  93  *    being used are not cryptographic related :-).
  94  * 4. If you include any Windows specific code (or a derivative thereof) from
  95  *    the apps directory (application code) you must include an acknowledgement:
  96  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
  97  *
  98  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  99  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 100  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 101  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 102  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 103  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 104  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 105  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 106  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 107  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 108  * SUCH DAMAGE.
 109  *
 110  * The licence and distribution terms for any publically available version or
 111  * derivative of this code cannot be changed.  i.e. this code cannot simply be
 112  * copied and put under another distribution licence
 113  * [including the GNU Public Licence.]
 114  */
 115
 116 #include <stdio.h>
 117 #include "ssl_locl.h"
 118 #ifndef OPENSSL_NO_COMP
 119 # include <openssl/comp.h>
 120 #endif
 121 #include <openssl/evp.h>
 122 #include <openssl/hmac.h>
 123 #include <openssl/md5.h>
 124 #include <openssl/rand.h>
 125 #ifdef KSSL_DEBUG
 126 # include <openssl/des.h>
 127 #endif
 128
 129 /*-
 130  * dtls1_enc encrypts/decrypts the record in |s->wrec| / |s->rrec|, respectively.
 131  *
 132  * Returns:
 133  *   0: (in non-constant time) if the record is publically invalid (i.e. too
 134  *       short etc).
 135  *   1: if the record's padding is valid / the encryption was successful.
 136  *   -1: if the record's padding/AEAD-authenticator is invalid or, if sending,
 137  *       an internal error occured.
 138  */
 139 int dtls1_enc(SSL *s, int send)
 140 {
 141     SSL3_RECORD *rec;
 142     EVP_CIPHER_CTX *ds;
 143     unsigned long l;
 144     int bs, i, j, k, mac_size = 0;
 145     const EVP_CIPHER *enc;
 146
 147     if (send) {
 148         if (EVP_MD_CTX_md(s->write_hash)) {
 149             mac_size = EVP_MD_CTX_size(s->write_hash);
 150             if (mac_size < 0)
 151                 return -1;
 152         }
 153         ds = s->enc_write_ctx;
 154         rec = &(s->s3->wrec);
 155         if (s->enc_write_ctx == NULL)
 156             enc = NULL;
 157         else {
 158             enc = EVP_CIPHER_CTX_cipher(s->enc_write_ctx);
 159             if (rec->data != rec->input)
 160                 /* we can't write into the input stream */
 161                 fprintf(stderr, "%s:%d: rec->data != rec->input\n",
 162                         __FILE__, __LINE__);
 163             else if (EVP_CIPHER_block_size(ds->cipher) > 1) {
 164                 if (RAND_bytes(rec->input, EVP_CIPHER_block_size(ds->cipher))
 165                     <= 0)
 166                     return -1;
 167             }
 168         }
 169     } else {
 170         if (EVP_MD_CTX_md(s->read_hash)) {
 171             mac_size = EVP_MD_CTX_size(s->read_hash);
 172             OPENSSL_assert(mac_size >= 0);
 173         }
 174         ds = s->enc_read_ctx;
 175         rec = &(s->s3->rrec);
 176         if (s->enc_read_ctx == NULL)
 177             enc = NULL;
 178         else
 179             enc = EVP_CIPHER_CTX_cipher(s->enc_read_ctx);
 180     }
 181
 182 #ifdef KSSL_DEBUG
 183     printf("dtls1_enc(%d)\n", send);
 184 #endif                          /* KSSL_DEBUG */
 185
 186     if ((s->session == NULL) || (ds == NULL) || (enc == NULL)) {
 187         memmove(rec->data, rec->input, rec->length);
 188         rec->input = rec->data;
 189     } else {
 190         l = rec->length;
 191         bs = EVP_CIPHER_block_size(ds->cipher);
 192
 193         if ((bs != 1) && send) {
 194             i = bs - ((int)l % bs);
 195
 196             /* Add weird padding of upto 256 bytes */
 197
 198             /* we need to add 'i' padding bytes of value j */
 199             j = i - 1;
 200             if (s->options & SSL_OP_TLS_BLOCK_PADDING_BUG) {
 201                 if (s->s3->flags & TLS1_FLAGS_TLS_PADDING_BUG)
 202                     j++;
 203             }
 204             for (k = (int)l; k < (int)(l + i); k++)
 205                 rec->input[k] = j;
 206             l += i;
 207             rec->length += i;
 208         }
 209 #ifdef KSSL_DEBUG
 210         {
 211             unsigned long ui;
 212             printf("EVP_Cipher(ds=%p,rec->data=%p,rec->input=%p,l=%ld) ==>\n",
 213                    ds, rec->data, rec->input, l);
 214             printf
 215                 ("\tEVP_CIPHER_CTX: %d buf_len, %d key_len [%d %d], %d iv_len\n",
 216                  ds->buf_len, ds->cipher->key_len, DES_KEY_SZ,
 217                  DES_SCHEDULE_SZ, ds->cipher->iv_len);
 218             printf("\t\tIV: ");
 219             for (i = 0; i < ds->cipher->iv_len; i++)
 220                 printf("%02X", ds->iv[i]);
 221             printf("\n");
 222             printf("\trec->input=");
 223             for (ui = 0; ui < l; ui++)
 224                 printf(" %02x", rec->input[ui]);
 225             printf("\n");
 226         }
 227 #endif                          /* KSSL_DEBUG */
 228
 229         if (!send) {
 230             if (l == 0 || l % bs != 0)
 231                 return 0;
 232         }
 233
 234         if (EVP_Cipher(ds, rec->data, rec->input, l) < 1)
 235             return -1;
 236
 237 #ifdef KSSL_DEBUG
 238         {
 239             unsigned long i;
 240             printf("\trec->data=");
 241             for (i = 0; i < l; i++)
 242                 printf(" %02x", rec->data[i]);
 243             printf("\n");
 244         }
 245 #endif                          /* KSSL_DEBUG */
 246
 247         if ((bs != 1) && !send)
 248             return tls1_cbc_remove_padding(s, rec, bs, mac_size);
 249     }
 250     return (1);
 251 }