xref: /freebsd/sys/crypto/sha2/sha256c.c (revision 87b759f0fa1f7554d50ce640c40138512bbded44)
1 /*-
2  * Copyright 2005 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 
27 #include <sys/cdefs.h>
28 #include <sys/endian.h>
29 #include <sys/types.h>
30 
31 #ifdef _KERNEL
32 #include <sys/systm.h>
33 #else
34 #include <string.h>
35 #endif
36 
37 #include "sha224.h"
38 #include "sha256.h"
39 #include "sha256c_impl.h"
40 
41 #if defined(ARM64_SHA2)
42 #include <sys/auxv.h>
43 #include <machine/ifunc.h>
44 #endif
45 
46 #if BYTE_ORDER == BIG_ENDIAN
47 
48 /* Copy a vector of big-endian uint32_t into a vector of bytes */
49 #define be32enc_vect(dst, src, len)	\
50 	memcpy((void *)dst, (const void *)src, (size_t)len)
51 
52 /* Copy a vector of bytes into a vector of big-endian uint32_t */
53 #define be32dec_vect(dst, src, len)	\
54 	memcpy((void *)dst, (const void *)src, (size_t)len)
55 
56 #else /* BYTE_ORDER != BIG_ENDIAN */
57 
58 /*
59  * Encode a length len/4 vector of (uint32_t) into a length len vector of
60  * (unsigned char) in big-endian form.  Assumes len is a multiple of 4.
61  */
62 static void
63 be32enc_vect(unsigned char *dst, const uint32_t *src, size_t len)
64 {
65 	size_t i;
66 
67 	for (i = 0; i < len / 4; i++)
68 		be32enc(dst + i * 4, src[i]);
69 }
70 
71 /*
72  * Decode a big-endian length len vector of (unsigned char) into a length
73  * len/4 vector of (uint32_t).  Assumes len is a multiple of 4.
74  */
75 static void
76 be32dec_vect(uint32_t *dst, const unsigned char *src, size_t len)
77 {
78 	size_t i;
79 
80 	for (i = 0; i < len / 4; i++)
81 		dst[i] = be32dec(src + i * 4);
82 }
83 
84 #endif /* BYTE_ORDER != BIG_ENDIAN */
85 
86 /* SHA256 round constants. */
87 static const uint32_t K[64] = {
88 	0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
89 	0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
90 	0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
91 	0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
92 	0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
93 	0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
94 	0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
95 	0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
96 	0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
97 	0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
98 	0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
99 	0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
100 	0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
101 	0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
102 	0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
103 	0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
104 };
105 
106 /* Elementary functions used by SHA256 */
107 #define Ch(x, y, z)	((x & (y ^ z)) ^ z)
108 #define Maj(x, y, z)	((x & (y | z)) | (y & z))
109 #define SHR(x, n)	(x >> n)
110 #define ROTR(x, n)	((x >> n) | (x << (32 - n)))
111 #define S0(x)		(ROTR(x, 2) ^ ROTR(x, 13) ^ ROTR(x, 22))
112 #define S1(x)		(ROTR(x, 6) ^ ROTR(x, 11) ^ ROTR(x, 25))
113 #define s0(x)		(ROTR(x, 7) ^ ROTR(x, 18) ^ SHR(x, 3))
114 #define s1(x)		(ROTR(x, 17) ^ ROTR(x, 19) ^ SHR(x, 10))
115 
116 /* SHA256 round function */
117 #define RND(a, b, c, d, e, f, g, h, k)			\
118 	h += S1(e) + Ch(e, f, g) + k;			\
119 	d += h;						\
120 	h += S0(a) + Maj(a, b, c);
121 
122 /* Adjusted round function for rotating state */
123 #define RNDr(S, W, i, ii)			\
124 	RND(S[(64 - i) % 8], S[(65 - i) % 8],	\
125 	    S[(66 - i) % 8], S[(67 - i) % 8],	\
126 	    S[(68 - i) % 8], S[(69 - i) % 8],	\
127 	    S[(70 - i) % 8], S[(71 - i) % 8],	\
128 	    W[i + ii] + K[i + ii])
129 
130 /* Message schedule computation */
131 #define MSCH(W, ii, i)				\
132 	W[i + ii + 16] = s1(W[i + ii + 14]) + W[i + ii + 9] + s0(W[i + ii + 1]) + W[i + ii]
133 
134 /*
135  * SHA256 block compression function.  The 256-bit state is transformed via
136  * the 512-bit input block to produce a new state.
137  */
138 static void
139 #if defined(ARM64_SHA2)
140 SHA256_Transform_c(uint32_t * state, const unsigned char block[64])
141 #else
142 SHA256_Transform(uint32_t * state, const unsigned char block[64])
143 #endif
144 {
145 	uint32_t W[64];
146 	uint32_t S[8];
147 	int i;
148 
149 	/* 1. Prepare the first part of the message schedule W. */
150 	be32dec_vect(W, block, 64);
151 
152 	/* 2. Initialize working variables. */
153 	memcpy(S, state, 32);
154 
155 	/* 3. Mix. */
156 	for (i = 0; i < 64; i += 16) {
157 		RNDr(S, W, 0, i);
158 		RNDr(S, W, 1, i);
159 		RNDr(S, W, 2, i);
160 		RNDr(S, W, 3, i);
161 		RNDr(S, W, 4, i);
162 		RNDr(S, W, 5, i);
163 		RNDr(S, W, 6, i);
164 		RNDr(S, W, 7, i);
165 		RNDr(S, W, 8, i);
166 		RNDr(S, W, 9, i);
167 		RNDr(S, W, 10, i);
168 		RNDr(S, W, 11, i);
169 		RNDr(S, W, 12, i);
170 		RNDr(S, W, 13, i);
171 		RNDr(S, W, 14, i);
172 		RNDr(S, W, 15, i);
173 
174 		if (i == 48)
175 			break;
176 		MSCH(W, 0, i);
177 		MSCH(W, 1, i);
178 		MSCH(W, 2, i);
179 		MSCH(W, 3, i);
180 		MSCH(W, 4, i);
181 		MSCH(W, 5, i);
182 		MSCH(W, 6, i);
183 		MSCH(W, 7, i);
184 		MSCH(W, 8, i);
185 		MSCH(W, 9, i);
186 		MSCH(W, 10, i);
187 		MSCH(W, 11, i);
188 		MSCH(W, 12, i);
189 		MSCH(W, 13, i);
190 		MSCH(W, 14, i);
191 		MSCH(W, 15, i);
192 	}
193 
194 	/* 4. Mix local working variables into global state */
195 	for (i = 0; i < 8; i++)
196 		state[i] += S[i];
197 }
198 
199 #if defined(ARM64_SHA2)
200 static void
201 SHA256_Transform_arm64(uint32_t * state, const unsigned char block[64])
202 {
203 	SHA256_Transform_arm64_impl(state, block, K);
204 }
205 
206 DEFINE_UIFUNC(static, void, SHA256_Transform,
207     (uint32_t * state, const unsigned char block[64]))
208 {
209 	u_long hwcap;
210 
211 	if (elf_aux_info(AT_HWCAP, &hwcap, sizeof(hwcap)) == 0) {
212 		if ((hwcap & HWCAP_SHA2) != 0)
213 			return (SHA256_Transform_arm64);
214 	}
215 
216 	return (SHA256_Transform_c);
217 }
218 #endif
219 
220 static unsigned char PAD[64] = {
221 	0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
222 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
223 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
224 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
225 };
226 
227 /* Add padding and terminating bit-count. */
228 static void
229 SHA256_Pad(SHA256_CTX * ctx)
230 {
231 	size_t r;
232 
233 	/* Figure out how many bytes we have buffered. */
234 	r = (ctx->count >> 3) & 0x3f;
235 
236 	/* Pad to 56 mod 64, transforming if we finish a block en route. */
237 	if (r < 56) {
238 		/* Pad to 56 mod 64. */
239 		memcpy(&ctx->buf[r], PAD, 56 - r);
240 	} else {
241 		/* Finish the current block and mix. */
242 		memcpy(&ctx->buf[r], PAD, 64 - r);
243 		SHA256_Transform(ctx->state, ctx->buf);
244 
245 		/* The start of the final block is all zeroes. */
246 		memset(&ctx->buf[0], 0, 56);
247 	}
248 
249 	/* Add the terminating bit-count. */
250 	be64enc(&ctx->buf[56], ctx->count);
251 
252 	/* Mix in the final block. */
253 	SHA256_Transform(ctx->state, ctx->buf);
254 }
255 
256 /* SHA-256 initialization.  Begins a SHA-256 operation. */
257 void
258 SHA256_Init(SHA256_CTX * ctx)
259 {
260 
261 	/* Zero bits processed so far */
262 	ctx->count = 0;
263 
264 	/* Magic initialization constants */
265 	ctx->state[0] = 0x6A09E667;
266 	ctx->state[1] = 0xBB67AE85;
267 	ctx->state[2] = 0x3C6EF372;
268 	ctx->state[3] = 0xA54FF53A;
269 	ctx->state[4] = 0x510E527F;
270 	ctx->state[5] = 0x9B05688C;
271 	ctx->state[6] = 0x1F83D9AB;
272 	ctx->state[7] = 0x5BE0CD19;
273 }
274 
275 /* Add bytes into the hash */
276 void
277 SHA256_Update(SHA256_CTX * ctx, const void *in, size_t len)
278 {
279 	uint64_t bitlen;
280 	uint32_t r;
281 	const unsigned char *src = in;
282 
283 	/* Number of bytes left in the buffer from previous updates */
284 	r = (ctx->count >> 3) & 0x3f;
285 
286 	/* Convert the length into a number of bits */
287 	bitlen = len << 3;
288 
289 	/* Update number of bits */
290 	ctx->count += bitlen;
291 
292 	/* Handle the case where we don't need to perform any transforms */
293 	if (len < 64 - r) {
294 		memcpy(&ctx->buf[r], src, len);
295 		return;
296 	}
297 
298 	/* Finish the current block */
299 	memcpy(&ctx->buf[r], src, 64 - r);
300 	SHA256_Transform(ctx->state, ctx->buf);
301 	src += 64 - r;
302 	len -= 64 - r;
303 
304 	/* Perform complete blocks */
305 	while (len >= 64) {
306 		SHA256_Transform(ctx->state, src);
307 		src += 64;
308 		len -= 64;
309 	}
310 
311 	/* Copy left over data into buffer */
312 	memcpy(ctx->buf, src, len);
313 }
314 
315 /*
316  * SHA-256 finalization.  Pads the input data, exports the hash value,
317  * and clears the context state.
318  */
319 void
320 SHA256_Final(unsigned char digest[static SHA256_DIGEST_LENGTH], SHA256_CTX *ctx)
321 {
322 
323 	/* Add padding */
324 	SHA256_Pad(ctx);
325 
326 	/* Write the hash */
327 	be32enc_vect(digest, ctx->state, SHA256_DIGEST_LENGTH);
328 
329 	/* Clear the context state */
330 	explicit_bzero(ctx, sizeof(*ctx));
331 }
332 
333 /*** SHA-224: *********************************************************/
334 /*
335  * the SHA224 and SHA256 transforms are identical
336  */
337 
338 /* SHA-224 initialization.  Begins a SHA-224 operation. */
339 void
340 SHA224_Init(SHA224_CTX * ctx)
341 {
342 
343 	/* Zero bits processed so far */
344 	ctx->count = 0;
345 
346 	/* Magic initialization constants */
347 	ctx->state[0] = 0xC1059ED8;
348 	ctx->state[1] = 0x367CD507;
349 	ctx->state[2] = 0x3070DD17;
350 	ctx->state[3] = 0xF70E5939;
351 	ctx->state[4] = 0xFFC00B31;
352 	ctx->state[5] = 0x68581511;
353 	ctx->state[6] = 0x64f98FA7;
354 	ctx->state[7] = 0xBEFA4FA4;
355 }
356 
357 /* Add bytes into the SHA-224 hash */
358 void
359 SHA224_Update(SHA224_CTX * ctx, const void *in, size_t len)
360 {
361 
362 	SHA256_Update((SHA256_CTX *)ctx, in, len);
363 }
364 
365 /*
366  * SHA-224 finalization.  Pads the input data, exports the hash value,
367  * and clears the context state.
368  */
369 void
370 SHA224_Final(unsigned char digest[static SHA224_DIGEST_LENGTH], SHA224_CTX *ctx)
371 {
372 
373 	/* Add padding */
374 	SHA256_Pad((SHA256_CTX *)ctx);
375 
376 	/* Write the hash */
377 	be32enc_vect(digest, ctx->state, SHA224_DIGEST_LENGTH);
378 
379 	/* Clear the context state */
380 	explicit_bzero(ctx, sizeof(*ctx));
381 }
382 
383 #ifdef WEAK_REFS
384 /* When building libmd, provide weak references. Note: this is not
385    activated in the context of compiling these sources for internal
386    use in libcrypt.
387  */
388 #undef SHA256_Init
389 __weak_reference(_libmd_SHA256_Init, SHA256_Init);
390 #undef SHA256_Update
391 __weak_reference(_libmd_SHA256_Update, SHA256_Update);
392 #undef SHA256_Final
393 __weak_reference(_libmd_SHA256_Final, SHA256_Final);
394 
395 #undef SHA224_Init
396 __weak_reference(_libmd_SHA224_Init, SHA224_Init);
397 #undef SHA224_Update
398 __weak_reference(_libmd_SHA224_Update, SHA224_Update);
399 #undef SHA224_Final
400 __weak_reference(_libmd_SHA224_Final, SHA224_Final);
401 #endif
402