1 /*-
2 * Copyright 2009 Colin Percival
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * This file was originally written by Colin Percival as part of the Tarsnap
27 * online backup system.
28 */
29 #include "scrypt_platform.h"
30
31 #include <sys/types.h>
32 #include <sys/mman.h>
33
34 #include <emmintrin.h>
35 #include <errno.h>
36 #include <stdint.h>
37 #include <stdlib.h>
38 #include <string.h>
39
40 #ifdef USE_OPENSSL_PBKDF2
41 #include <openssl/evp.h>
42 #else
43 #include "sha256.h"
44 #endif
45 #include "sysendian.h"
46
47 #include "crypto_scrypt.h"
48
49 static void blkcpy(void *, void *, size_t);
50 static void blkxor(void *, void *, size_t);
51 static void salsa20_8(__m128i *);
52 static void blockmix_salsa8(__m128i *, __m128i *, __m128i *, size_t);
53 static uint64_t integerify(void *, size_t);
54 static void smix(uint8_t *, size_t, uint64_t, void *, void *);
55
56 static void
blkcpy(void * dest,void * src,size_t len)57 blkcpy(void * dest, void * src, size_t len)
58 {
59 __m128i * D = dest;
60 __m128i * S = src;
61 size_t L = len / 16;
62 size_t i;
63
64 for (i = 0; i < L; i++)
65 D[i] = S[i];
66 }
67
68 static void
blkxor(void * dest,void * src,size_t len)69 blkxor(void * dest, void * src, size_t len)
70 {
71 __m128i * D = dest;
72 __m128i * S = src;
73 size_t L = len / 16;
74 size_t i;
75
76 for (i = 0; i < L; i++)
77 D[i] = _mm_xor_si128(D[i], S[i]);
78 }
79
80 /**
81 * salsa20_8(B):
82 * Apply the salsa20/8 core to the provided block.
83 */
84 static void
salsa20_8(__m128i B[4])85 salsa20_8(__m128i B[4])
86 {
87 __m128i X0, X1, X2, X3;
88 __m128i T;
89 size_t i;
90
91 X0 = B[0];
92 X1 = B[1];
93 X2 = B[2];
94 X3 = B[3];
95
96 for (i = 0; i < 8; i += 2) {
97 /* Operate on "columns". */
98 T = _mm_add_epi32(X0, X3);
99 X1 = _mm_xor_si128(X1, _mm_slli_epi32(T, 7));
100 X1 = _mm_xor_si128(X1, _mm_srli_epi32(T, 25));
101 T = _mm_add_epi32(X1, X0);
102 X2 = _mm_xor_si128(X2, _mm_slli_epi32(T, 9));
103 X2 = _mm_xor_si128(X2, _mm_srli_epi32(T, 23));
104 T = _mm_add_epi32(X2, X1);
105 X3 = _mm_xor_si128(X3, _mm_slli_epi32(T, 13));
106 X3 = _mm_xor_si128(X3, _mm_srli_epi32(T, 19));
107 T = _mm_add_epi32(X3, X2);
108 X0 = _mm_xor_si128(X0, _mm_slli_epi32(T, 18));
109 X0 = _mm_xor_si128(X0, _mm_srli_epi32(T, 14));
110
111 /* Rearrange data. */
112 X1 = _mm_shuffle_epi32(X1, 0x93);
113 X2 = _mm_shuffle_epi32(X2, 0x4E);
114 X3 = _mm_shuffle_epi32(X3, 0x39);
115
116 /* Operate on "rows". */
117 T = _mm_add_epi32(X0, X1);
118 X3 = _mm_xor_si128(X3, _mm_slli_epi32(T, 7));
119 X3 = _mm_xor_si128(X3, _mm_srli_epi32(T, 25));
120 T = _mm_add_epi32(X3, X0);
121 X2 = _mm_xor_si128(X2, _mm_slli_epi32(T, 9));
122 X2 = _mm_xor_si128(X2, _mm_srli_epi32(T, 23));
123 T = _mm_add_epi32(X2, X3);
124 X1 = _mm_xor_si128(X1, _mm_slli_epi32(T, 13));
125 X1 = _mm_xor_si128(X1, _mm_srli_epi32(T, 19));
126 T = _mm_add_epi32(X1, X2);
127 X0 = _mm_xor_si128(X0, _mm_slli_epi32(T, 18));
128 X0 = _mm_xor_si128(X0, _mm_srli_epi32(T, 14));
129
130 /* Rearrange data. */
131 X1 = _mm_shuffle_epi32(X1, 0x39);
132 X2 = _mm_shuffle_epi32(X2, 0x4E);
133 X3 = _mm_shuffle_epi32(X3, 0x93);
134 }
135
136 B[0] = _mm_add_epi32(B[0], X0);
137 B[1] = _mm_add_epi32(B[1], X1);
138 B[2] = _mm_add_epi32(B[2], X2);
139 B[3] = _mm_add_epi32(B[3], X3);
140 }
141
142 /**
143 * blockmix_salsa8(Bin, Bout, X, r):
144 * Compute Bout = BlockMix_{salsa20/8, r}(Bin). The input Bin must be 128r
145 * bytes in length; the output Bout must also be the same size. The
146 * temporary space X must be 64 bytes.
147 */
148 static void
blockmix_salsa8(__m128i * Bin,__m128i * Bout,__m128i * X,size_t r)149 blockmix_salsa8(__m128i * Bin, __m128i * Bout, __m128i * X, size_t r)
150 {
151 size_t i;
152
153 /* 1: X <-- B_{2r - 1} */
154 blkcpy(X, &Bin[8 * r - 4], 64);
155
156 /* 2: for i = 0 to 2r - 1 do */
157 for (i = 0; i < r; i++) {
158 /* 3: X <-- H(X \xor B_i) */
159 blkxor(X, &Bin[i * 8], 64);
160 salsa20_8(X);
161
162 /* 4: Y_i <-- X */
163 /* 6: B' <-- (Y_0, Y_2 ... Y_{2r-2}, Y_1, Y_3 ... Y_{2r-1}) */
164 blkcpy(&Bout[i * 4], X, 64);
165
166 /* 3: X <-- H(X \xor B_i) */
167 blkxor(X, &Bin[i * 8 + 4], 64);
168 salsa20_8(X);
169
170 /* 4: Y_i <-- X */
171 /* 6: B' <-- (Y_0, Y_2 ... Y_{2r-2}, Y_1, Y_3 ... Y_{2r-1}) */
172 blkcpy(&Bout[(r + i) * 4], X, 64);
173 }
174 }
175
176 /**
177 * integerify(B, r):
178 * Return the result of parsing B_{2r-1} as a little-endian integer.
179 */
180 static uint64_t
integerify(void * B,size_t r)181 integerify(void * B, size_t r)
182 {
183 uint32_t * X = (void *)((uintptr_t)(B) + (2 * r - 1) * 64);
184
185 return (((uint64_t)(X[13]) << 32) + X[0]);
186 }
187
188 /**
189 * smix(B, r, N, V, XY):
190 * Compute B = SMix_r(B, N). The input B must be 128r bytes in length;
191 * the temporary storage V must be 128rN bytes in length; the temporary
192 * storage XY must be 256r + 64 bytes in length. The value N must be a
193 * power of 2 greater than 1. The arrays B, V, and XY must be aligned to a
194 * multiple of 64 bytes.
195 */
196 static void
smix(uint8_t * B,size_t r,uint64_t N,void * V,void * XY)197 smix(uint8_t * B, size_t r, uint64_t N, void * V, void * XY)
198 {
199 __m128i * X = XY;
200 __m128i * Y = (void *)((uintptr_t)(XY) + 128 * r);
201 __m128i * Z = (void *)((uintptr_t)(XY) + 256 * r);
202 uint32_t * X32 = (void *)X;
203 uint64_t i, j;
204 size_t k;
205
206 /* 1: X <-- B */
207 for (k = 0; k < 2 * r; k++) {
208 for (i = 0; i < 16; i++) {
209 X32[k * 16 + i] =
210 le32dec(&B[(k * 16 + (i * 5 % 16)) * 4]);
211 }
212 }
213
214 /* 2: for i = 0 to N - 1 do */
215 for (i = 0; i < N; i += 2) {
216 /* 3: V_i <-- X */
217 blkcpy((void *)((uintptr_t)(V) + i * 128 * r), X, 128 * r);
218
219 /* 4: X <-- H(X) */
220 blockmix_salsa8(X, Y, Z, r);
221
222 /* 3: V_i <-- X */
223 blkcpy((void *)((uintptr_t)(V) + (i + 1) * 128 * r),
224 Y, 128 * r);
225
226 /* 4: X <-- H(X) */
227 blockmix_salsa8(Y, X, Z, r);
228 }
229
230 /* 6: for i = 0 to N - 1 do */
231 for (i = 0; i < N; i += 2) {
232 /* 7: j <-- Integerify(X) mod N */
233 j = integerify(X, r) & (N - 1);
234
235 /* 8: X <-- H(X \xor V_j) */
236 blkxor(X, (void *)((uintptr_t)(V) + j * 128 * r), 128 * r);
237 blockmix_salsa8(X, Y, Z, r);
238
239 /* 7: j <-- Integerify(X) mod N */
240 j = integerify(Y, r) & (N - 1);
241
242 /* 8: X <-- H(X \xor V_j) */
243 blkxor(Y, (void *)((uintptr_t)(V) + j * 128 * r), 128 * r);
244 blockmix_salsa8(Y, X, Z, r);
245 }
246
247 /* 10: B' <-- X */
248 for (k = 0; k < 2 * r; k++) {
249 for (i = 0; i < 16; i++) {
250 le32enc(&B[(k * 16 + (i * 5 % 16)) * 4],
251 X32[k * 16 + i]);
252 }
253 }
254 }
255
256 /**
257 * crypto_scrypt(passwd, passwdlen, salt, saltlen, N, r, p, buf, buflen):
258 * Compute scrypt(passwd[0 .. passwdlen - 1], salt[0 .. saltlen - 1], N, r,
259 * p, buflen) and write the result into buf. The parameters r, p, and buflen
260 * must satisfy r * p < 2^30 and buflen <= (2^32 - 1) * 32. The parameter N
261 * must be a power of 2 greater than 1.
262 *
263 * Return 0 on success; or -1 on error.
264 */
265 int
crypto_scrypt(const uint8_t * passwd,size_t passwdlen,const uint8_t * salt,size_t saltlen,uint64_t N,uint32_t r,uint32_t p,uint8_t * buf,size_t buflen)266 crypto_scrypt(const uint8_t * passwd, size_t passwdlen,
267 const uint8_t * salt, size_t saltlen, uint64_t N, uint32_t r, uint32_t p,
268 uint8_t * buf, size_t buflen)
269 {
270 void * B0, * V0, * XY0;
271 uint8_t * B;
272 uint32_t * V;
273 uint32_t * XY;
274 uint32_t i;
275
276 /* Sanity-check parameters. */
277 #if SIZE_MAX > UINT32_MAX
278 if (buflen > (((uint64_t)(1) << 32) - 1) * 32) {
279 errno = EFBIG;
280 goto err0;
281 }
282 #endif
283 if ((uint64_t)(r) * (uint64_t)(p) >= (1 << 30)) {
284 errno = EFBIG;
285 goto err0;
286 }
287 if (((N & (N - 1)) != 0) || (N == 0)) {
288 errno = EINVAL;
289 goto err0;
290 }
291 if ((r > SIZE_MAX / 128 / p) ||
292 #if SIZE_MAX / 256 <= UINT32_MAX
293 (r > (SIZE_MAX - 64) / 256) ||
294 #endif
295 (N > SIZE_MAX / 128 / r)) {
296 errno = ENOMEM;
297 goto err0;
298 }
299
300 /* Allocate memory. */
301 #ifdef HAVE_POSIX_MEMALIGN
302 if ((errno = posix_memalign(&B0, 64, 128 * r * p)) != 0)
303 goto err0;
304 B = (uint8_t *)(B0);
305 if ((errno = posix_memalign(&XY0, 64, 256 * r + 64)) != 0)
306 goto err1;
307 XY = (uint32_t *)(XY0);
308 #ifndef MAP_ANON
309 if ((errno = posix_memalign(&V0, 64, 128 * r * N)) != 0)
310 goto err2;
311 V = (uint32_t *)(V0);
312 #endif
313 #else
314 if ((B0 = malloc(128 * r * p + 63)) == NULL)
315 goto err0;
316 B = (uint8_t *)(((uintptr_t)(B0) + 63) & ~ (uintptr_t)(63));
317 if ((XY0 = malloc(256 * r + 64 + 63)) == NULL)
318 goto err1;
319 XY = (uint32_t *)(((uintptr_t)(XY0) + 63) & ~ (uintptr_t)(63));
320 #ifndef MAP_ANON
321 if ((V0 = malloc(128 * r * N + 63)) == NULL)
322 goto err2;
323 V = (uint32_t *)(((uintptr_t)(V0) + 63) & ~ (uintptr_t)(63));
324 #endif
325 #endif
326 #ifdef MAP_ANON
327 if ((V0 = mmap(NULL, 128 * r * N, PROT_READ | PROT_WRITE,
328 #ifdef MAP_NOCORE
329 MAP_ANON | MAP_PRIVATE | MAP_NOCORE,
330 #else
331 MAP_ANON | MAP_PRIVATE,
332 #endif
333 -1, 0)) == MAP_FAILED)
334 goto err2;
335 V = (uint32_t *)(V0);
336 #endif
337
338 /* 1: (B_0 ... B_{p-1}) <-- PBKDF2(P, S, 1, p * MFLen) */
339 #ifdef USE_OPENSSL_PBKDF2
340 PKCS5_PBKDF2_HMAC((const char *)passwd, passwdlen, salt, saltlen, 1, EVP_sha256(), p * 128 * r, B);
341 #else
342 PBKDF2_SHA256(passwd, passwdlen, salt, saltlen, 1, B, p * 128 * r);
343 #endif
344
345 /* 2: for i = 0 to p - 1 do */
346 for (i = 0; i < p; i++) {
347 /* 3: B_i <-- MF(B_i, N) */
348 smix(&B[i * 128 * r], r, N, V, XY);
349 }
350
351 /* 5: DK <-- PBKDF2(P, B, 1, dkLen) */
352 #ifdef USE_OPENSSL_PBKDF2
353 PKCS5_PBKDF2_HMAC((const char *)passwd, passwdlen, B, p * 128 * r, 1, EVP_sha256(), buflen, buf);
354 #else
355 PBKDF2_SHA256(passwd, passwdlen, B, p * 128 * r, 1, buf, buflen);
356 #endif
357
358 /* Free memory. */
359 #ifdef MAP_ANON
360 if (munmap(V0, 128 * r * N))
361 goto err2;
362 #else
363 free(V0);
364 #endif
365 free(XY0);
366 free(B0);
367
368 /* Success! */
369 return (0);
370
371 err2:
372 free(XY0);
373 err1:
374 free(B0);
375 err0:
376 /* Failure! */
377 return (-1);
378 }
379