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git.proxmox.com Git - mirror_frr.git/blob - lib/sha256.c
2 * Copyright 2005,2007,2009 Colin Percival
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
30 #if !HAVE_DECL_BE32DEC
31 static inline uint32_t be32dec(const void *pp
)
33 const uint8_t *p
= (uint8_t const *)pp
;
35 return ((uint32_t)(p
[3]) + ((uint32_t)(p
[2]) << 8)
36 + ((uint32_t)(p
[1]) << 16) + ((uint32_t)(p
[0]) << 24));
40 #if !HAVE_DECL_BE32ENC
41 static inline void be32enc(void *pp
, uint32_t x
)
43 uint8_t *p
= (uint8_t *)pp
;
46 p
[2] = (x
>> 8) & 0xff;
47 p
[1] = (x
>> 16) & 0xff;
48 p
[0] = (x
>> 24) & 0xff;
53 * Encode a length len/4 vector of (uint32_t) into a length len vector of
54 * (unsigned char) in big-endian form. Assumes len is a multiple of 4.
56 static void be32enc_vect(unsigned char *dst
, const uint32_t *src
, size_t len
)
60 for (i
= 0; i
< len
/ 4; i
++)
61 be32enc(dst
+ i
* 4, src
[i
]);
65 * Decode a big-endian length len vector of (unsigned char) into a length
66 * len/4 vector of (uint32_t). Assumes len is a multiple of 4.
68 static void be32dec_vect(uint32_t *dst
, const unsigned char *src
, size_t len
)
72 for (i
= 0; i
< len
/ 4; i
++)
73 dst
[i
] = be32dec(src
+ i
* 4);
76 /* Elementary functions used by SHA256 */
77 #define Ch(x, y, z) ((x & (y ^ z)) ^ z)
78 #define Maj(x, y, z) ((x & (y | z)) | (y & z))
79 #define SHR(x, n) (x >> n)
80 #define ROTR(x, n) ((x >> n) | (x << (32 - n)))
81 #define S0(x) (ROTR(x, 2) ^ ROTR(x, 13) ^ ROTR(x, 22))
82 #define S1(x) (ROTR(x, 6) ^ ROTR(x, 11) ^ ROTR(x, 25))
83 #define s0(x) (ROTR(x, 7) ^ ROTR(x, 18) ^ SHR(x, 3))
84 #define s1(x) (ROTR(x, 17) ^ ROTR(x, 19) ^ SHR(x, 10))
86 /* SHA256 round function */
87 #define RND(a, b, c, d, e, f, g, h, k) \
88 t0 = h + S1(e) + Ch(e, f, g) + k; \
89 t1 = S0(a) + Maj(a, b, c); \
93 /* Adjusted round function for rotating state */
94 #define RNDr(S, W, i, k) \
95 RND(S[(64 - i) % 8], S[(65 - i) % 8], S[(66 - i) % 8], \
96 S[(67 - i) % 8], S[(68 - i) % 8], S[(69 - i) % 8], \
97 S[(70 - i) % 8], S[(71 - i) % 8], W[i] + k)
100 * SHA256 block compression function. The 256-bit state is transformed via
101 * the 512-bit input block to produce a new state.
103 static void SHA256_Transform(uint32_t *state
, const unsigned char block
[64])
110 /* 1. Prepare message schedule W. */
111 be32dec_vect(W
, block
, 64);
112 for (i
= 16; i
< 64; i
++)
113 W
[i
] = s1(W
[i
- 2]) + W
[i
- 7] + s0(W
[i
- 15]) + W
[i
- 16];
115 /* 2. Initialize working variables. */
116 memcpy(S
, state
, 32);
119 RNDr(S
, W
, 0, 0x428a2f98);
120 RNDr(S
, W
, 1, 0x71374491);
121 RNDr(S
, W
, 2, 0xb5c0fbcf);
122 RNDr(S
, W
, 3, 0xe9b5dba5);
123 RNDr(S
, W
, 4, 0x3956c25b);
124 RNDr(S
, W
, 5, 0x59f111f1);
125 RNDr(S
, W
, 6, 0x923f82a4);
126 RNDr(S
, W
, 7, 0xab1c5ed5);
127 RNDr(S
, W
, 8, 0xd807aa98);
128 RNDr(S
, W
, 9, 0x12835b01);
129 RNDr(S
, W
, 10, 0x243185be);
130 RNDr(S
, W
, 11, 0x550c7dc3);
131 RNDr(S
, W
, 12, 0x72be5d74);
132 RNDr(S
, W
, 13, 0x80deb1fe);
133 RNDr(S
, W
, 14, 0x9bdc06a7);
134 RNDr(S
, W
, 15, 0xc19bf174);
135 RNDr(S
, W
, 16, 0xe49b69c1);
136 RNDr(S
, W
, 17, 0xefbe4786);
137 RNDr(S
, W
, 18, 0x0fc19dc6);
138 RNDr(S
, W
, 19, 0x240ca1cc);
139 RNDr(S
, W
, 20, 0x2de92c6f);
140 RNDr(S
, W
, 21, 0x4a7484aa);
141 RNDr(S
, W
, 22, 0x5cb0a9dc);
142 RNDr(S
, W
, 23, 0x76f988da);
143 RNDr(S
, W
, 24, 0x983e5152);
144 RNDr(S
, W
, 25, 0xa831c66d);
145 RNDr(S
, W
, 26, 0xb00327c8);
146 RNDr(S
, W
, 27, 0xbf597fc7);
147 RNDr(S
, W
, 28, 0xc6e00bf3);
148 RNDr(S
, W
, 29, 0xd5a79147);
149 RNDr(S
, W
, 30, 0x06ca6351);
150 RNDr(S
, W
, 31, 0x14292967);
151 RNDr(S
, W
, 32, 0x27b70a85);
152 RNDr(S
, W
, 33, 0x2e1b2138);
153 RNDr(S
, W
, 34, 0x4d2c6dfc);
154 RNDr(S
, W
, 35, 0x53380d13);
155 RNDr(S
, W
, 36, 0x650a7354);
156 RNDr(S
, W
, 37, 0x766a0abb);
157 RNDr(S
, W
, 38, 0x81c2c92e);
158 RNDr(S
, W
, 39, 0x92722c85);
159 RNDr(S
, W
, 40, 0xa2bfe8a1);
160 RNDr(S
, W
, 41, 0xa81a664b);
161 RNDr(S
, W
, 42, 0xc24b8b70);
162 RNDr(S
, W
, 43, 0xc76c51a3);
163 RNDr(S
, W
, 44, 0xd192e819);
164 RNDr(S
, W
, 45, 0xd6990624);
165 RNDr(S
, W
, 46, 0xf40e3585);
166 RNDr(S
, W
, 47, 0x106aa070);
167 RNDr(S
, W
, 48, 0x19a4c116);
168 RNDr(S
, W
, 49, 0x1e376c08);
169 RNDr(S
, W
, 50, 0x2748774c);
170 RNDr(S
, W
, 51, 0x34b0bcb5);
171 RNDr(S
, W
, 52, 0x391c0cb3);
172 RNDr(S
, W
, 53, 0x4ed8aa4a);
173 RNDr(S
, W
, 54, 0x5b9cca4f);
174 RNDr(S
, W
, 55, 0x682e6ff3);
175 RNDr(S
, W
, 56, 0x748f82ee);
176 RNDr(S
, W
, 57, 0x78a5636f);
177 RNDr(S
, W
, 58, 0x84c87814);
178 RNDr(S
, W
, 59, 0x8cc70208);
179 RNDr(S
, W
, 60, 0x90befffa);
180 RNDr(S
, W
, 61, 0xa4506ceb);
181 RNDr(S
, W
, 62, 0xbef9a3f7);
182 RNDr(S
, W
, 63, 0xc67178f2);
184 /* 4. Mix local working variables into global state */
185 for (i
= 0; i
< 8; i
++)
188 /* Clean the stack. */
191 memset(&t0
, 0, sizeof(t0
));
192 memset(&t1
, 0, sizeof(t0
));
195 static unsigned char PAD
[64] = {
196 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
197 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
198 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
200 /* Add padding and terminating bit-count. */
201 static void SHA256_Pad(SHA256_CTX
*ctx
)
203 unsigned char len
[8];
207 * Convert length to a vector of bytes -- we do this now rather
208 * than later because the length will change after we pad.
210 be32enc_vect(len
, ctx
->count
, 8);
212 /* Add 1--64 bytes so that the resulting length is 56 mod 64 */
213 r
= (ctx
->count
[1] >> 3) & 0x3f;
214 plen
= (r
< 56) ? (56 - r
) : (120 - r
);
215 SHA256_Update(ctx
, PAD
, (size_t)plen
);
217 /* Add the terminating bit-count */
218 SHA256_Update(ctx
, len
, 8);
221 /* SHA-256 initialization. Begins a SHA-256 operation. */
222 void SHA256_Init(SHA256_CTX
*ctx
)
225 /* Zero bits processed so far */
226 ctx
->count
[0] = ctx
->count
[1] = 0;
228 /* Magic initialization constants */
229 ctx
->state
[0] = 0x6A09E667;
230 ctx
->state
[1] = 0xBB67AE85;
231 ctx
->state
[2] = 0x3C6EF372;
232 ctx
->state
[3] = 0xA54FF53A;
233 ctx
->state
[4] = 0x510E527F;
234 ctx
->state
[5] = 0x9B05688C;
235 ctx
->state
[6] = 0x1F83D9AB;
236 ctx
->state
[7] = 0x5BE0CD19;
239 /* Add bytes into the hash */
240 void SHA256_Update(SHA256_CTX
*ctx
, const void *in
, size_t len
)
244 const unsigned char *src
= in
;
246 /* Number of bytes left in the buffer from previous updates */
247 r
= (ctx
->count
[1] >> 3) & 0x3f;
249 /* Convert the length into a number of bits */
250 bitlen
[1] = ((uint32_t)len
) << 3;
251 bitlen
[0] = (uint32_t)(len
>> 29);
253 /* Update number of bits */
254 if ((ctx
->count
[1] += bitlen
[1]) < bitlen
[1])
256 ctx
->count
[0] += bitlen
[0];
258 /* Handle the case where we don't need to perform any transforms */
260 memcpy(&ctx
->buf
[r
], src
, len
);
264 /* Finish the current block */
265 memcpy(&ctx
->buf
[r
], src
, 64 - r
);
266 SHA256_Transform(ctx
->state
, ctx
->buf
);
270 /* Perform complete blocks */
272 SHA256_Transform(ctx
->state
, src
);
277 /* Copy left over data into buffer */
278 memcpy(ctx
->buf
, src
, len
);
282 * SHA-256 finalization. Pads the input data, exports the hash value,
283 * and clears the context state.
285 void SHA256_Final(unsigned char digest
[32], SHA256_CTX
*ctx
)
292 be32enc_vect(digest
, ctx
->state
, 32);
294 /* Clear the context state */
295 memset((void *)ctx
, 0, sizeof(*ctx
));
298 /* Initialize an HMAC-SHA256 operation with the given key. */
299 void HMAC__SHA256_Init(HMAC_SHA256_CTX
*ctx
, const void *_K
, size_t Klen
)
301 unsigned char pad
[64];
302 unsigned char khash
[32];
303 const unsigned char *K
= _K
;
306 /* If Klen > 64, the key is really SHA256(K). */
308 SHA256_Init(&ctx
->ictx
);
309 SHA256_Update(&ctx
->ictx
, K
, Klen
);
310 SHA256_Final(khash
, &ctx
->ictx
);
315 /* Inner SHA256 operation is SHA256(K xor [block of 0x36] || data). */
316 SHA256_Init(&ctx
->ictx
);
317 memset(pad
, 0x36, 64);
318 for (i
= 0; i
< Klen
; i
++)
320 SHA256_Update(&ctx
->ictx
, pad
, 64);
322 /* Outer SHA256 operation is SHA256(K xor [block of 0x5c] || hash). */
323 SHA256_Init(&ctx
->octx
);
324 memset(pad
, 0x5c, 64);
325 for (i
= 0; i
< Klen
; i
++)
327 SHA256_Update(&ctx
->octx
, pad
, 64);
329 /* Clean the stack. */
330 memset(khash
, 0, 32);
333 /* Add bytes to the HMAC-SHA256 operation. */
334 void HMAC__SHA256_Update(HMAC_SHA256_CTX
*ctx
, const void *in
, size_t len
)
337 /* Feed data to the inner SHA256 operation. */
338 SHA256_Update(&ctx
->ictx
, in
, len
);
341 /* Finish an HMAC-SHA256 operation. */
342 void HMAC__SHA256_Final(unsigned char digest
[32], HMAC_SHA256_CTX
*ctx
)
344 unsigned char ihash
[32];
346 /* Finish the inner SHA256 operation. */
347 SHA256_Final(ihash
, &ctx
->ictx
);
349 /* Feed the inner hash to the outer SHA256 operation. */
350 SHA256_Update(&ctx
->octx
, ihash
, 32);
352 /* Finish the outer SHA256 operation. */
353 SHA256_Final(digest
, &ctx
->octx
);
355 /* Clean the stack. */
356 memset(ihash
, 0, 32);
360 * PBKDF2_SHA256(passwd, passwdlen, salt, saltlen, c, buf, dkLen):
361 * Compute PBKDF2(passwd, salt, c, dkLen) using HMAC-SHA256 as the PRF, and
362 * write the output to buf. The value dkLen must be at most 32 * (2^32 - 1).
364 void PBKDF2_SHA256(const uint8_t *passwd
, size_t passwdlen
, const uint8_t *salt
,
365 size_t saltlen
, uint64_t c
, uint8_t *buf
, size_t dkLen
)
367 HMAC_SHA256_CTX PShctx
, hctx
;
376 /* Compute HMAC state after processing P and S. */
377 HMAC__SHA256_Init(&PShctx
, passwd
, passwdlen
);
378 HMAC__SHA256_Update(&PShctx
, salt
, saltlen
);
380 /* Iterate through the blocks. */
381 for (i
= 0; i
* 32 < dkLen
; i
++) {
382 /* Generate INT(i + 1). */
383 be32enc(ivec
, (uint32_t)(i
+ 1));
385 /* Compute U_1 = PRF(P, S || INT(i)). */
386 memcpy(&hctx
, &PShctx
, sizeof(HMAC_SHA256_CTX
));
387 HMAC__SHA256_Update(&hctx
, ivec
, 4);
388 HMAC__SHA256_Final(U
, &hctx
);
393 for (j
= 2; j
<= c
; j
++) {
395 HMAC__SHA256_Init(&hctx
, passwd
, passwdlen
);
396 HMAC__SHA256_Update(&hctx
, U
, 32);
397 HMAC__SHA256_Final(U
, &hctx
);
399 /* ... xor U_j ... */
400 for (k
= 0; k
< 32; k
++)
404 /* Copy as many bytes as necessary into buf. */
405 clen
= dkLen
- i
* 32;
408 memcpy(&buf
[i
* 32], T
, clen
);
411 /* Clean PShctx, since we never called _Final on it. */
412 memset(&PShctx
, 0, sizeof(HMAC_SHA256_CTX
));