xref: /dflybsd-src/sys/crypto/blake2/blake2s.c (revision 03517d4e1314f46a8bc390aa6bcb929361ee0569)
1  /*	$OpenBSD: blake2s.c,v 1.3 2023/02/03 18:31:16 miod Exp $	*/
2  /*
3   * Copyright (C) 2012 Samuel Neves <sneves@dei.uc.pt>. All Rights Reserved.
4   * Copyright (C) 2015-2020 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
5   *
6   * Permission to use, copy, modify, and distribute this software for any
7   * purpose with or without fee is hereby granted, provided that the above
8   * copyright notice and this permission notice appear in all copies.
9   *
10   * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11   * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12   * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13   * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14   * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15   * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16   * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17   *
18   * This is an implementation of the BLAKE2s hash and PRF functions.
19   * Information: https://blake2.net/
20   */
21  
22  #include <sys/types.h>
23  #include <sys/systm.h>
24  #include <sys/endian.h>
25  
26  #include <crypto/blake2/blake2s.h>
27  
28  static inline uint32_t ror32(uint32_t word, unsigned int shift)
29  {
30  	return (word >> shift) | (word << (32 - shift));
31  }
32  
33  static const uint32_t blake2s_iv[8] = {
34  	0x6A09E667UL, 0xBB67AE85UL, 0x3C6EF372UL, 0xA54FF53AUL,
35  	0x510E527FUL, 0x9B05688CUL, 0x1F83D9ABUL, 0x5BE0CD19UL
36  };
37  
38  static const uint8_t blake2s_sigma[10][16] = {
39  	{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 },
40  	{ 14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0, 2, 11, 7, 5, 3 },
41  	{ 11, 8, 12, 0, 5, 2, 15, 13, 10, 14, 3, 6, 7, 1, 9, 4 },
42  	{ 7, 9, 3, 1, 13, 12, 11, 14, 2, 6, 5, 10, 4, 0, 15, 8 },
43  	{ 9, 0, 5, 7, 2, 4, 10, 15, 14, 1, 11, 12, 6, 8, 3, 13 },
44  	{ 2, 12, 6, 10, 0, 11, 8, 3, 4, 13, 7, 5, 15, 14, 1, 9 },
45  	{ 12, 5, 1, 15, 14, 13, 4, 10, 0, 7, 6, 3, 9, 2, 8, 11 },
46  	{ 13, 11, 7, 14, 12, 1, 3, 9, 5, 0, 15, 4, 8, 6, 2, 10 },
47  	{ 6, 15, 14, 9, 11, 3, 0, 8, 12, 2, 13, 7, 1, 4, 10, 5 },
48  	{ 10, 2, 8, 4, 7, 6, 1, 5, 15, 11, 9, 14, 3, 12, 13, 0 },
49  };
50  
51  static inline void blake2s_set_lastblock(struct blake2s_state *state)
52  {
53  	state->f[0] = -1;
54  }
55  
56  static inline void blake2s_increment_counter(struct blake2s_state *state,
57  					     uint32_t inc)
58  {
59  	state->t[0] += inc;
60  	state->t[1] += (state->t[0] < inc);
61  }
62  
63  static inline void blake2s_init_param(struct blake2s_state *state,
64  				      uint32_t param)
65  {
66  	int i;
67  
68  	memset(state, 0, sizeof(*state));
69  	for (i = 0; i < 8; ++i)
70  		state->h[i] = blake2s_iv[i];
71  	state->h[0] ^= param;
72  }
73  
74  void blake2s_init(struct blake2s_state *state, size_t outlen)
75  {
76  	KKASSERT(!(!outlen || outlen > BLAKE2S_HASH_SIZE));
77  	blake2s_init_param(state, 0x01010000 | outlen);
78  	state->outlen = outlen;
79  }
80  
81  void blake2s_init_key(struct blake2s_state *state, size_t outlen,
82  		      const void *key, size_t keylen)
83  {
84  	uint8_t block[BLAKE2S_BLOCK_SIZE] = { 0 };
85  
86  	KKASSERT(!(!outlen || outlen > BLAKE2S_HASH_SIZE ||
87  		   !key || !keylen || keylen > BLAKE2S_KEY_SIZE));
88  
89  	blake2s_init_param(state, 0x01010000 | keylen << 8 | outlen);
90  	state->outlen = outlen;
91  	memcpy(block, key, keylen);
92  	blake2s_update(state, block, BLAKE2S_BLOCK_SIZE);
93  	explicit_bzero(block, BLAKE2S_BLOCK_SIZE);
94  }
95  
96  static inline void blake2s_compress(struct blake2s_state *state,
97  				    const uint8_t *block, size_t nblocks,
98  				    uint32_t inc)
99  {
100  	uint32_t m[16];
101  	uint32_t v[16];
102  	int i;
103  
104  	KKASSERT(!((nblocks > 1 && inc != BLAKE2S_BLOCK_SIZE)));
105  
106  	while (nblocks > 0) {
107  		blake2s_increment_counter(state, inc);
108  		memcpy(m, block, BLAKE2S_BLOCK_SIZE);
109  		for (i = 0; i < 16; i++)
110  			m[i] = le32toh(m[i]);
111  		memcpy(v, state->h, 32);
112  		v[ 8] = blake2s_iv[0];
113  		v[ 9] = blake2s_iv[1];
114  		v[10] = blake2s_iv[2];
115  		v[11] = blake2s_iv[3];
116  		v[12] = blake2s_iv[4] ^ state->t[0];
117  		v[13] = blake2s_iv[5] ^ state->t[1];
118  		v[14] = blake2s_iv[6] ^ state->f[0];
119  		v[15] = blake2s_iv[7] ^ state->f[1];
120  
121  #define G(r, i, a, b, c, d) do { \
122  	a += b + m[blake2s_sigma[r][2 * i + 0]]; \
123  	d = ror32(d ^ a, 16); \
124  	c += d; \
125  	b = ror32(b ^ c, 12); \
126  	a += b + m[blake2s_sigma[r][2 * i + 1]]; \
127  	d = ror32(d ^ a, 8); \
128  	c += d; \
129  	b = ror32(b ^ c, 7); \
130  } while (0)
131  
132  #define ROUND(r) do { \
133  	G(r, 0, v[0], v[ 4], v[ 8], v[12]); \
134  	G(r, 1, v[1], v[ 5], v[ 9], v[13]); \
135  	G(r, 2, v[2], v[ 6], v[10], v[14]); \
136  	G(r, 3, v[3], v[ 7], v[11], v[15]); \
137  	G(r, 4, v[0], v[ 5], v[10], v[15]); \
138  	G(r, 5, v[1], v[ 6], v[11], v[12]); \
139  	G(r, 6, v[2], v[ 7], v[ 8], v[13]); \
140  	G(r, 7, v[3], v[ 4], v[ 9], v[14]); \
141  } while (0)
142  		ROUND(0);
143  		ROUND(1);
144  		ROUND(2);
145  		ROUND(3);
146  		ROUND(4);
147  		ROUND(5);
148  		ROUND(6);
149  		ROUND(7);
150  		ROUND(8);
151  		ROUND(9);
152  
153  #undef G
154  #undef ROUND
155  
156  		for (i = 0; i < 8; ++i)
157  			state->h[i] ^= v[i] ^ v[i + 8];
158  
159  		block += BLAKE2S_BLOCK_SIZE;
160  		--nblocks;
161  	}
162  }
163  
164  void blake2s_update(struct blake2s_state *state, const uint8_t *in, size_t inlen)
165  {
166  	const size_t fill = BLAKE2S_BLOCK_SIZE - state->buflen;
167  
168  	if (!inlen)
169  		return;
170  	if (inlen > fill) {
171  		memcpy(state->buf + state->buflen, in, fill);
172  		blake2s_compress(state, state->buf, 1, BLAKE2S_BLOCK_SIZE);
173  		state->buflen = 0;
174  		in += fill;
175  		inlen -= fill;
176  	}
177  	if (inlen > BLAKE2S_BLOCK_SIZE) {
178  		const size_t nblocks =
179  			(inlen + BLAKE2S_BLOCK_SIZE - 1) / BLAKE2S_BLOCK_SIZE;
180  		/* Hash one less (full) block than strictly possible */
181  		blake2s_compress(state, in, nblocks - 1, BLAKE2S_BLOCK_SIZE);
182  		in += BLAKE2S_BLOCK_SIZE * (nblocks - 1);
183  		inlen -= BLAKE2S_BLOCK_SIZE * (nblocks - 1);
184  	}
185  	memcpy(state->buf + state->buflen, in, inlen);
186  	state->buflen += inlen;
187  }
188  
189  void blake2s_final(struct blake2s_state *state, uint8_t *out)
190  {
191  	int i;
192  	blake2s_set_lastblock(state);
193  	memset(state->buf + state->buflen, 0,
194  	       BLAKE2S_BLOCK_SIZE - state->buflen); /* Padding */
195  	blake2s_compress(state, state->buf, 1, state->buflen);
196  	for (i = 0; i < 8; i++)
197  		state->h[i] = htole32(state->h[i]);
198  	memcpy(out, state->h, state->outlen);
199  	explicit_bzero(state, sizeof(*state));
200  }
201  
202  void blake2s_hmac(uint8_t *out, const uint8_t *in, const uint8_t *key,
203  		  size_t outlen, size_t inlen, size_t keylen)
204  {
205  	struct blake2s_state state;
206  	uint8_t x_key[BLAKE2S_BLOCK_SIZE] __aligned(__alignof__(uint32_t)) = { 0 };
207  	uint8_t i_hash[BLAKE2S_HASH_SIZE] __aligned(__alignof__(uint32_t));
208  	int i;
209  
210  	if (keylen > BLAKE2S_BLOCK_SIZE) {
211  		blake2s_init(&state, BLAKE2S_HASH_SIZE);
212  		blake2s_update(&state, key, keylen);
213  		blake2s_final(&state, x_key);
214  	} else
215  		memcpy(x_key, key, keylen);
216  
217  	for (i = 0; i < BLAKE2S_BLOCK_SIZE; ++i)
218  		x_key[i] ^= 0x36;
219  
220  	blake2s_init(&state, BLAKE2S_HASH_SIZE);
221  	blake2s_update(&state, x_key, BLAKE2S_BLOCK_SIZE);
222  	blake2s_update(&state, in, inlen);
223  	blake2s_final(&state, i_hash);
224  
225  	for (i = 0; i < BLAKE2S_BLOCK_SIZE; ++i)
226  		x_key[i] ^= 0x5c ^ 0x36;
227  
228  	blake2s_init(&state, BLAKE2S_HASH_SIZE);
229  	blake2s_update(&state, x_key, BLAKE2S_BLOCK_SIZE);
230  	blake2s_update(&state, i_hash, BLAKE2S_HASH_SIZE);
231  	blake2s_final(&state, i_hash);
232  
233  	memcpy(out, i_hash, outlen);
234  	explicit_bzero(x_key, BLAKE2S_BLOCK_SIZE);
235  	explicit_bzero(i_hash, BLAKE2S_HASH_SIZE);
236  }
237