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 #include <openssl/engine.h>
  55 #include <openssl/rand.h>
  56 #include <openssl/err.h>
  57 
  58 #if (defined(__i386)   || defined(__i386__)   || defined(_M_IX86) || \
  59      defined(__x86_64) || defined(__x86_64__) || \
  60      defined(_M_AMD64) || defined (_M_X64)) && defined(OPENSSL_CPUID_OBJ)
  61 
  62 size_t OPENSSL_ia32_rdrand(void);
  63 
  64 static int get_random_bytes (unsigned char *buf, int num)
  65         {
  66         size_t rnd;
  67 
  68         while (num>=(int)sizeof(size_t)) {
  69                 if ((rnd = OPENSSL_ia32_rdrand()) == 0) return 0;
  70 
  71                 *((size_t *)buf) = rnd;
  72                 buf += sizeof(size_t);
  73                 num -= sizeof(size_t);
  74         }
  75         if (num) {
  76                 if ((rnd = OPENSSL_ia32_rdrand()) == 0) return 0;
  77 
  78                 memcpy (buf,&rnd,num);
  79         }
  80 
  81         return 1;
  82         }
  83 
  84 static int random_status (void)
  85 {       return 1;       }
  86 
  87 static RAND_METHOD rdrand_meth =
  88         {
  89         NULL,   /* seed */
  90         get_random_bytes,
  91         NULL,   /* cleanup */
  92         NULL,   /* add */
  93         get_random_bytes,
  94         random_status,
  95         };
  96 
  97 static int rdrand_init(ENGINE *e)
  98 {       return 1;       }
  99 
 100 static const char *engine_e_rdrand_id = "rdrand";
 101 static const char *engine_e_rdrand_name = "Intel RDRAND engine";
 102 
 103 static int bind_helper(ENGINE *e)
 104         {
 105         if (!ENGINE_set_id(e, engine_e_rdrand_id) ||
 106             !ENGINE_set_name(e, engine_e_rdrand_name) ||
 107             !ENGINE_set_flags(e, ENGINE_FLAGS_NO_REGISTER_ALL) ||
 108             !ENGINE_set_init_function(e, rdrand_init) ||
 109             !ENGINE_set_RAND(e, &rdrand_meth) )
 110                 return 0;
 111 
 112         return 1;
 113         }
 114 
 115 static ENGINE *ENGINE_rdrand(void)
 116         {
 117         ENGINE *ret = ENGINE_new();
 118         if(!ret)
 119                 return NULL;
 120         if(!bind_helper(ret))
 121                 {
 122                 ENGINE_free(ret);
 123                 return NULL;
 124                 }
 125         return ret;
 126         }
 127 
 128 void ENGINE_load_rdrand (void)
 129         {
 130         extern unsigned int OPENSSL_ia32cap_P[];
 131 
 132         if (OPENSSL_ia32cap_P[1] & (1<<(62-32)))
 133                 {
 134                 ENGINE *toadd = ENGINE_rdrand();
 135                 if(!toadd) return;
 136                 ENGINE_add(toadd);
 137                 ENGINE_free(toadd);
 138                 ERR_clear_error();
 139                 }
 140         }
 141 #else
 142 void ENGINE_load_rdrand (void) {}
 143 #endif