crypto/evp/scrypt.c

   1 /*
   2  * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project
   3  * 2015.
   4  */
   5 /* ====================================================================
   6  * Copyright (c) 2015 The OpenSSL Project.  All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  *
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in
  17  *    the documentation and/or other materials provided with the
  18  *    distribution.
  19  *
  20  * 3. All advertising materials mentioning features or use of this
  21  *    software must display the following acknowledgment:
  22  *    "This product includes software developed by the OpenSSL Project
  23  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
  24  *
  25  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  26  *    endorse or promote products derived from this software without
  27  *    prior written permission. For written permission, please contact
  28  *    licensing@OpenSSL.org.
  29  *
  30  * 5. Products derived from this software may not be called "OpenSSL"
  31  *    nor may "OpenSSL" appear in their names without prior written
  32  *    permission of the OpenSSL Project.
  33  *
  34  * 6. Redistributions of any form whatsoever must retain the following
  35  *    acknowledgment:
  36  *    "This product includes software developed by the OpenSSL Project
  37  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  38  *
  39  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  40  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  41  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  42  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  43  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  44  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  45  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  46  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  48  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  49  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  50  * OF THE POSSIBILITY OF SUCH DAMAGE.
  51  * ====================================================================
  52  *
  53  * This product includes cryptographic software written by Eric Young
  54  * (eay@cryptsoft.com).  This product includes software written by Tim
  55  * Hudson (tjh@cryptsoft.com).
  56  *
  57  */
  58
  59 #include <stddef.h>
  60 #include <stdio.h>
  61 #include <string.h>
  62 #include <openssl/evp.h>
  63 #include <openssl/err.h>
  64 #include <internal/numbers.h>
  65
  66 #ifndef OPENSSL_NO_SCRYPT
  67
  68 #define R(a,b) (((a) << (b)) | ((a) >> (32 - (b))))
  69 static void salsa208_word_specification(uint32_t inout[16])
  70 {
  71     int i;
  72     uint32_t x[16];
  73     memcpy(x, inout, sizeof(x));
  74     for (i = 8; i > 0; i -= 2) {
  75         x[4] ^= R(x[0] + x[12], 7);
  76         x[8] ^= R(x[4] + x[0], 9);
  77         x[12] ^= R(x[8] + x[4], 13);
  78         x[0] ^= R(x[12] + x[8], 18);
  79         x[9] ^= R(x[5] + x[1], 7);
  80         x[13] ^= R(x[9] + x[5], 9);
  81         x[1] ^= R(x[13] + x[9], 13);
  82         x[5] ^= R(x[1] + x[13], 18);
  83         x[14] ^= R(x[10] + x[6], 7);
  84         x[2] ^= R(x[14] + x[10], 9);
  85         x[6] ^= R(x[2] + x[14], 13);
  86         x[10] ^= R(x[6] + x[2], 18);
  87         x[3] ^= R(x[15] + x[11], 7);
  88         x[7] ^= R(x[3] + x[15], 9);
  89         x[11] ^= R(x[7] + x[3], 13);
  90         x[15] ^= R(x[11] + x[7], 18);
  91         x[1] ^= R(x[0] + x[3], 7);
  92         x[2] ^= R(x[1] + x[0], 9);
  93         x[3] ^= R(x[2] + x[1], 13);
  94         x[0] ^= R(x[3] + x[2], 18);
  95         x[6] ^= R(x[5] + x[4], 7);
  96         x[7] ^= R(x[6] + x[5], 9);
  97         x[4] ^= R(x[7] + x[6], 13);
  98         x[5] ^= R(x[4] + x[7], 18);
  99         x[11] ^= R(x[10] + x[9], 7);
 100         x[8] ^= R(x[11] + x[10], 9);
 101         x[9] ^= R(x[8] + x[11], 13);
 102         x[10] ^= R(x[9] + x[8], 18);
 103         x[12] ^= R(x[15] + x[14], 7);
 104         x[13] ^= R(x[12] + x[15], 9);
 105         x[14] ^= R(x[13] + x[12], 13);
 106         x[15] ^= R(x[14] + x[13], 18);
 107     }
 108     for (i = 0; i < 16; ++i)
 109         inout[i] += x[i];
 110     OPENSSL_cleanse(x, sizeof(x));
 111 }
 112
 113 static void scryptBlockMix(uint32_t *B_, uint32_t *B, uint64_t r)
 114 {
 115     uint64_t i, j;
 116     uint32_t X[16], *pB;
 117
 118     memcpy(X, B + (r * 2 - 1) * 16, sizeof(X));
 119     pB = B;
 120     for (i = 0; i < r * 2; i++) {
 121         for (j = 0; j < 16; j++)
 122             X[j] ^= *pB++;
 123         salsa208_word_specification(X);
 124         memcpy(B_ + (i / 2 + (i & 1) * r) * 16, X, sizeof(X));
 125     }
 126     OPENSSL_cleanse(X, sizeof(X));
 127 }
 128
 129 static void scryptROMix(unsigned char *B, uint64_t r, uint64_t N,
 130                         uint32_t *X, uint32_t *T, uint32_t *V)
 131 {
 132     unsigned char *pB;
 133     uint32_t *pV;
 134     uint64_t i, k;
 135
 136     /* Convert from little endian input */
 137     for (pV = V, i = 0, pB = B; i < 32 * r; i++, pV++) {
 138         *pV = *pB++;
 139         *pV |= *pB++ << 8;
 140         *pV |= *pB++ << 16;
 141         *pV |= (uint32_t)*pB++ << 24;
 142     }
 143
 144     for (i = 1; i < N; i++, pV += 32 * r)
 145         scryptBlockMix(pV, pV - 32 * r, r);
 146
 147     scryptBlockMix(X, V + (N - 1) * 32 * r, r);
 148
 149     for (i = 0; i < N; i++) {
 150         uint32_t j;
 151         j = X[16 * (2 * r - 1)] % N;
 152         pV = V + 32 * r * j;
 153         for (k = 0; k < 32 * r; k++)
 154             T[k] = X[k] ^ *pV++;
 155         scryptBlockMix(X, T, r);
 156     }
 157     /* Convert output to little endian */
 158     for (i = 0, pB = B; i < 32 * r; i++) {
 159         uint32_t xtmp = X[i];
 160         *pB++ = xtmp & 0xff;
 161         *pB++ = (xtmp >> 8) & 0xff;
 162         *pB++ = (xtmp >> 16) & 0xff;
 163         *pB++ = (xtmp >> 24) & 0xff;
 164     }
 165 }
 166
 167 #ifndef SIZE_MAX
 168 # define SIZE_MAX    ((size_t)-1)
 169 #endif
 170
 171 /*
 172  * Maximum power of two that will fit in uint64_t: this should work on
 173  * most (all?) platforms.
 174  */
 175
 176 #define LOG2_UINT64_MAX         (sizeof(uint64_t) * 8 - 1)
 177
 178 /*
 179  * Maximum value of p * r:
 180  * p <= ((2^32-1) * hLen) / MFLen =>
 181  * p <= ((2^32-1) * 32) / (128 * r) =>
 182  * p * r <= (2^30-1)
 183  *
 184  */
 185
 186 #define SCRYPT_PR_MAX   ((1 << 30) - 1)
 187
 188 /*
 189  * Maximum permitted memory allow this to be overridden with Configuration
 190  * option: e.g. -DSCRYPT_MAX_MEM=0 for maximum possible.
 191  */
 192
 193 #ifdef SCRYPT_MAX_MEM
 194 # if SCRYPT_MAX_MEM == 0
 195 #  undef SCRYPT_MAX_MEM
 196 /*
 197  * Although we could theoretically allocate SIZE_MAX memory that would leave
 198  * no memory available for anything else so set limit as half that.
 199  */
 200 #  define SCRYPT_MAX_MEM (SIZE_MAX/2)
 201 # endif
 202 #else
 203 /* Default memory limit: 32 MB */
 204 # define SCRYPT_MAX_MEM  (1024 * 1024 * 32)
 205 #endif
 206
 207 int EVP_PBE_scrypt(const char *pass, size_t passlen,
 208                    const unsigned char *salt, size_t saltlen,
 209                    uint64_t N, uint64_t r, uint64_t p, uint64_t maxmem,
 210                    unsigned char *key, size_t keylen)
 211 {
 212     int rv = 0;
 213     unsigned char *B;
 214     uint32_t *X, *V, *T;
 215     uint64_t i, Blen, Vlen;
 216
 217     /* Sanity check parameters */
 218     /* initial check, r,p must be non zero, N >= 2 and a power of 2 */
 219     if (r == 0 || p == 0 || N < 2 || (N & (N - 1)))
 220         return 0;
 221     /* Check p * r < SCRYPT_PR_MAX avoiding overflow */
 222     if (p > SCRYPT_PR_MAX / r)
 223         return 0;
 224
 225     /*
 226      * Need to check N: if 2^(128 * r / 8) overflows limit this is
 227      * automatically satisfied since N <= UINT64_MAX.
 228      */
 229
 230     if (16 * r <= LOG2_UINT64_MAX) {
 231         if (N >= (1UL << (16 * r)))
 232             return 0;
 233     }
 234
 235     /* Memory checks: check total allocated buffer size fits in uint64_t */
 236
 237     /*
 238      * B size in section 5 step 1.S
 239      * Note: we know p * 128 * r < UINT64_MAX because we already checked
 240      * p * r < SCRYPT_PR_MAX
 241      */
 242     Blen = p * 128 * r;
 243
 244     /*
 245      * Check 32 * r * (N + 2) * sizeof(uint32_t) fits in uint64_t.
 246      * This is combined size V, X and T (section 4)
 247      */
 248     i = UINT64_MAX / (32 * sizeof(uint32_t));
 249     if (N + 2 > i / r)
 250         return 0;
 251     Vlen = 32 * r * (N + 2) * sizeof(uint32_t);
 252
 253     /* check total allocated size fits in uint64_t */
 254     if (Blen > UINT64_MAX - Vlen)
 255         return 0;
 256
 257     if (maxmem == 0)
 258         maxmem = SCRYPT_MAX_MEM;
 259
 260     if (Blen + Vlen > maxmem) {
 261         EVPerr(EVP_F_EVP_PBE_SCRYPT, EVP_R_MEMORY_LIMIT_EXCEEDED);
 262         return 0;
 263     }
 264
 265     /* If no key return to indicate parameters are OK */
 266     if (key == NULL)
 267         return 1;
 268
 269     B = OPENSSL_malloc(Blen + Vlen);
 270     if (B == NULL)
 271         return 0;
 272     X = (uint32_t *)(B + Blen);
 273     T = X + 32 * r;
 274     V = T + 32 * r;
 275     if (PKCS5_PBKDF2_HMAC(pass, passlen, salt, saltlen, 1, EVP_sha256(),
 276                           Blen, B) == 0)
 277         goto err;
 278
 279     for (i = 0; i < p; i++)
 280         scryptROMix(B + 128 * r * i, r, N, X, T, V);
 281
 282     if (PKCS5_PBKDF2_HMAC(pass, passlen, B, Blen, 1, EVP_sha256(),
 283                           keylen, key) == 0)
 284         goto err;
 285     rv = 1;
 286 #ifdef SCRYPT_DEBUG
 287     fprintf(stderr, "scrypt parameters:\n");
 288     fprintf(stderr, "N=%lu, p=%lu, r=%lu\n", N, p, r);
 289     fprintf(stderr, "Salt:\n");
 290     BIO_dump_fp(stderr, (char *)salt, saltlen);
 291     fprintf(stderr, "Password:\n");
 292     BIO_dump_fp(stderr, (char *)pass, passlen);
 293     fprintf(stderr, "Key:\n");
 294     BIO_dump_fp(stderr, (char *)key, keylen);
 295 #endif
 296  err:
 297     OPENSSL_clear_free(B, Blen + Vlen);
 298     return rv;
 299 }
 300 #endif