crypto/evp/e_rc4_hmac_md5.c

   1 /* ====================================================================
   2  * Copyright (c) 2011 The OpenSSL Project.  All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  *
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  *
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in
  13  *    the documentation and/or other materials provided with the
  14  *    distribution.
  15  *
  16  * 3. All advertising materials mentioning features or use of this
  17  *    software must display the following acknowledgment:
  18  *    "This product includes software developed by the OpenSSL Project
  19  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
  20  *
  21  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  22  *    endorse or promote products derived from this software without
  23  *    prior written permission. For written permission, please contact
  24  *    licensing@OpenSSL.org.
  25  *
  26  * 5. Products derived from this software may not be called "OpenSSL"
  27  *    nor may "OpenSSL" appear in their names without prior written
  28  *    permission of the OpenSSL Project.
  29  *
  30  * 6. Redistributions of any form whatsoever must retain the following
  31  *    acknowledgment:
  32  *    "This product includes software developed by the OpenSSL Project
  33  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  34  *
  35  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  36  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  37  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  38  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  39  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  40  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  41  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  42  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  43  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  44  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  45  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  46  * OF THE POSSIBILITY OF SUCH DAMAGE.
  47  * ====================================================================
  48  */
  49
  50 #include <openssl/opensslconf.h>
  51
  52 #include <stdio.h>
  53 #include <string.h>
  54
  55 #if !defined(OPENSSL_NO_RC4) && !defined(OPENSSL_NO_MD5)
  56
  57 # include <openssl/crypto.h>
  58 # include <openssl/evp.h>
  59 # include <openssl/objects.h>
  60 # include <openssl/rc4.h>
  61 # include <openssl/md5.h>
  62 # include "internal/evp_int.h"
  63
  64 # ifndef EVP_CIPH_FLAG_AEAD_CIPHER
  65 #  define EVP_CIPH_FLAG_AEAD_CIPHER       0x200000
  66 #  define EVP_CTRL_AEAD_TLS1_AAD          0x16
  67 #  define EVP_CTRL_AEAD_SET_MAC_KEY       0x17
  68 # endif
  69
  70 /* FIXME: surely this is available elsewhere? */
  71 # define EVP_RC4_KEY_SIZE                16
  72
  73 typedef struct {
  74     RC4_KEY ks;
  75     MD5_CTX head, tail, md;
  76     size_t payload_length;
  77 } EVP_RC4_HMAC_MD5;
  78
  79 # define NO_PAYLOAD_LENGTH       ((size_t)-1)
  80
  81 void rc4_md5_enc(RC4_KEY *key, const void *in0, void *out,
  82                  MD5_CTX *ctx, const void *inp, size_t blocks);
  83
  84 # define data(ctx) ((EVP_RC4_HMAC_MD5 *)EVP_CIPHER_CTX_get_cipher_data(ctx))
  85
  86 static int rc4_hmac_md5_init_key(EVP_CIPHER_CTX *ctx,
  87                                  const unsigned char *inkey,
  88                                  const unsigned char *iv, int enc)
  89 {
  90     EVP_RC4_HMAC_MD5 *key = data(ctx);
  91
  92     RC4_set_key(&key->ks, EVP_CIPHER_CTX_key_length(ctx), inkey);
  93
  94     MD5_Init(&key->head);       /* handy when benchmarking */
  95     key->tail = key->head;
  96     key->md = key->head;
  97
  98     key->payload_length = NO_PAYLOAD_LENGTH;
  99
 100     return 1;
 101 }
 102
 103 # if     !defined(OPENSSL_NO_ASM) &&     ( \
 104         defined(__x86_64)       || defined(__x86_64__)  || \
 105         defined(_M_AMD64)       || defined(_M_X64)      )
 106 #  define STITCHED_CALL
 107 # endif
 108
 109 # if !defined(STITCHED_CALL)
 110 #  define rc4_off 0
 111 #  define md5_off 0
 112 # endif
 113
 114 static int rc4_hmac_md5_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
 115                                const unsigned char *in, size_t len)
 116 {
 117     EVP_RC4_HMAC_MD5 *key = data(ctx);
 118 # if defined(STITCHED_CALL)
 119     size_t rc4_off = 32 - 1 - (key->ks.x & (32 - 1)), /* 32 is $MOD from
 120                                                        * rc4_md5-x86_64.pl */
 121         md5_off = MD5_CBLOCK - key->md.num, blocks;
 122     unsigned int l;
 123     extern unsigned int OPENSSL_ia32cap_P[];
 124 # endif
 125     size_t plen = key->payload_length;
 126
 127     if (plen != NO_PAYLOAD_LENGTH && len != (plen + MD5_DIGEST_LENGTH))
 128         return 0;
 129
 130     if (EVP_CIPHER_CTX_encrypting(ctx)) {
 131         if (plen == NO_PAYLOAD_LENGTH)
 132             plen = len;
 133 # if defined(STITCHED_CALL)
 134         /* cipher has to "fall behind" */
 135         if (rc4_off > md5_off)
 136             md5_off += MD5_CBLOCK;
 137
 138         if (plen > md5_off && (blocks = (plen - md5_off) / MD5_CBLOCK) &&
 139             (OPENSSL_ia32cap_P[0] & (1 << 20)) == 0) {
 140             MD5_Update(&key->md, in, md5_off);
 141             RC4(&key->ks, rc4_off, in, out);
 142
 143             rc4_md5_enc(&key->ks, in + rc4_off, out + rc4_off,
 144                         &key->md, in + md5_off, blocks);
 145             blocks *= MD5_CBLOCK;
 146             rc4_off += blocks;
 147             md5_off += blocks;
 148             key->md.Nh += blocks >> 29;
 149             key->md.Nl += blocks <<= 3;
 150             if (key->md.Nl < (unsigned int)blocks)
 151                 key->md.Nh++;
 152         } else {
 153             rc4_off = 0;
 154             md5_off = 0;
 155         }
 156 # endif
 157         MD5_Update(&key->md, in + md5_off, plen - md5_off);
 158
 159         if (plen != len) {      /* "TLS" mode of operation */
 160             if (in != out)
 161                 memcpy(out + rc4_off, in + rc4_off, plen - rc4_off);
 162
 163             /* calculate HMAC and append it to payload */
 164             MD5_Final(out + plen, &key->md);
 165             key->md = key->tail;
 166             MD5_Update(&key->md, out + plen, MD5_DIGEST_LENGTH);
 167             MD5_Final(out + plen, &key->md);
 168             /* encrypt HMAC at once */
 169             RC4(&key->ks, len - rc4_off, out + rc4_off, out + rc4_off);
 170         } else {
 171             RC4(&key->ks, len - rc4_off, in + rc4_off, out + rc4_off);
 172         }
 173     } else {
 174         unsigned char mac[MD5_DIGEST_LENGTH];
 175 # if defined(STITCHED_CALL)
 176         /* digest has to "fall behind" */
 177         if (md5_off > rc4_off)
 178             rc4_off += 2 * MD5_CBLOCK;
 179         else
 180             rc4_off += MD5_CBLOCK;
 181
 182         if (len > rc4_off && (blocks = (len - rc4_off) / MD5_CBLOCK) &&
 183             (OPENSSL_ia32cap_P[0] & (1 << 20)) == 0) {
 184             RC4(&key->ks, rc4_off, in, out);
 185             MD5_Update(&key->md, out, md5_off);
 186
 187             rc4_md5_enc(&key->ks, in + rc4_off, out + rc4_off,
 188                         &key->md, out + md5_off, blocks);
 189             blocks *= MD5_CBLOCK;
 190             rc4_off += blocks;
 191             md5_off += blocks;
 192             l = (key->md.Nl + (blocks << 3)) & 0xffffffffU;
 193             if (l < key->md.Nl)
 194                 key->md.Nh++;
 195             key->md.Nl = l;
 196             key->md.Nh += blocks >> 29;
 197         } else {
 198             md5_off = 0;
 199             rc4_off = 0;
 200         }
 201 # endif
 202         /* decrypt HMAC at once */
 203         RC4(&key->ks, len - rc4_off, in + rc4_off, out + rc4_off);
 204         if (plen != NO_PAYLOAD_LENGTH) { /* "TLS" mode of operation */
 205             MD5_Update(&key->md, out + md5_off, plen - md5_off);
 206
 207             /* calculate HMAC and verify it */
 208             MD5_Final(mac, &key->md);
 209             key->md = key->tail;
 210             MD5_Update(&key->md, mac, MD5_DIGEST_LENGTH);
 211             MD5_Final(mac, &key->md);
 212
 213             if (CRYPTO_memcmp(out + plen, mac, MD5_DIGEST_LENGTH))
 214                 return 0;
 215         } else {
 216             MD5_Update(&key->md, out + md5_off, len - md5_off);
 217         }
 218     }
 219
 220     key->payload_length = NO_PAYLOAD_LENGTH;
 221
 222     return 1;
 223 }
 224
 225 static int rc4_hmac_md5_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg,
 226                              void *ptr)
 227 {
 228     EVP_RC4_HMAC_MD5 *key = data(ctx);
 229
 230     switch (type) {
 231     case EVP_CTRL_AEAD_SET_MAC_KEY:
 232         {
 233             unsigned int i;
 234             unsigned char hmac_key[64];
 235
 236             memset(hmac_key, 0, sizeof(hmac_key));
 237
 238             if (arg > (int)sizeof(hmac_key)) {
 239                 MD5_Init(&key->head);
 240                 MD5_Update(&key->head, ptr, arg);
 241                 MD5_Final(hmac_key, &key->head);
 242             } else {
 243                 memcpy(hmac_key, ptr, arg);
 244             }
 245
 246             for (i = 0; i < sizeof(hmac_key); i++)
 247                 hmac_key[i] ^= 0x36; /* ipad */
 248             MD5_Init(&key->head);
 249             MD5_Update(&key->head, hmac_key, sizeof(hmac_key));
 250
 251             for (i = 0; i < sizeof(hmac_key); i++)
 252                 hmac_key[i] ^= 0x36 ^ 0x5c; /* opad */
 253             MD5_Init(&key->tail);
 254             MD5_Update(&key->tail, hmac_key, sizeof(hmac_key));
 255
 256             return 1;
 257         }
 258     case EVP_CTRL_AEAD_TLS1_AAD:
 259         {
 260             unsigned char *p = ptr;
 261             unsigned int len;
 262
 263             if (arg != EVP_AEAD_TLS1_AAD_LEN)
 264                 return -1;
 265
 266             len = p[arg - 2] << 8 | p[arg - 1];
 267
 268             if (!EVP_CIPHER_CTX_encrypting(ctx)) {
 269                 len -= MD5_DIGEST_LENGTH;
 270                 p[arg - 2] = len >> 8;
 271                 p[arg - 1] = len;
 272             }
 273             key->payload_length = len;
 274             key->md = key->head;
 275             MD5_Update(&key->md, p, arg);
 276
 277             return MD5_DIGEST_LENGTH;
 278         }
 279     default:
 280         return -1;
 281     }
 282 }
 283
 284 static EVP_CIPHER r4_hmac_md5_cipher = {
 285 # ifdef NID_rc4_hmac_md5
 286     NID_rc4_hmac_md5,
 287 # else
 288     NID_undef,
 289 # endif
 290     1, EVP_RC4_KEY_SIZE, 0,
 291     EVP_CIPH_STREAM_CIPHER | EVP_CIPH_VARIABLE_LENGTH |
 292         EVP_CIPH_FLAG_AEAD_CIPHER,
 293     rc4_hmac_md5_init_key,
 294     rc4_hmac_md5_cipher,
 295     NULL,
 296     sizeof(EVP_RC4_HMAC_MD5),
 297     NULL,
 298     NULL,
 299     rc4_hmac_md5_ctrl,
 300     NULL
 301 };
 302
 303 const EVP_CIPHER *EVP_rc4_hmac_md5(void)
 304 {
 305     return (&r4_hmac_md5_cipher);
 306 }
 307 #endif