1/*
2 * SHA-256 hash implementation and interface functions
3 * Copyright (c) 2003-2011, Jouni Malinen <j@w1.fi>
4 *
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
7 */
8
9#include "includes.h"
10
11#include "common.h"
12#include "sha256.h"
13#include "sha256_i.h"
14#include "crypto.h"
15
16
17/**
18 * sha256_vector - SHA256 hash for data vector
19 * @num_elem: Number of elements in the data vector
20 * @addr: Pointers to the data areas
21 * @len: Lengths of the data blocks
22 * @mac: Buffer for the hash
23 * Returns: 0 on success, -1 of failure
24 */
25int sha256_vector(size_t num_elem, const u8 *addr[], const size_t *len,
26		  u8 *mac)
27{
28	struct sha256_state ctx;
29	size_t i;
30
31	if (TEST_FAIL())
32		return -1;
33
34	sha256_init(&ctx);
35	for (i = 0; i < num_elem; i++)
36		if (sha256_process(&ctx, addr[i], len[i]))
37			return -1;
38	if (sha256_done(&ctx, mac))
39		return -1;
40	return 0;
41}
42
43
44/* ===== start - public domain SHA256 implementation ===== */
45
46/* This is based on SHA256 implementation in LibTomCrypt that was released into
47 * public domain by Tom St Denis. */
48
49/* the K array */
50static const unsigned long K[64] = {
51	0x428a2f98UL, 0x71374491UL, 0xb5c0fbcfUL, 0xe9b5dba5UL, 0x3956c25bUL,
52	0x59f111f1UL, 0x923f82a4UL, 0xab1c5ed5UL, 0xd807aa98UL, 0x12835b01UL,
53	0x243185beUL, 0x550c7dc3UL, 0x72be5d74UL, 0x80deb1feUL, 0x9bdc06a7UL,
54	0xc19bf174UL, 0xe49b69c1UL, 0xefbe4786UL, 0x0fc19dc6UL, 0x240ca1ccUL,
55	0x2de92c6fUL, 0x4a7484aaUL, 0x5cb0a9dcUL, 0x76f988daUL, 0x983e5152UL,
56	0xa831c66dUL, 0xb00327c8UL, 0xbf597fc7UL, 0xc6e00bf3UL, 0xd5a79147UL,
57	0x06ca6351UL, 0x14292967UL, 0x27b70a85UL, 0x2e1b2138UL, 0x4d2c6dfcUL,
58	0x53380d13UL, 0x650a7354UL, 0x766a0abbUL, 0x81c2c92eUL, 0x92722c85UL,
59	0xa2bfe8a1UL, 0xa81a664bUL, 0xc24b8b70UL, 0xc76c51a3UL, 0xd192e819UL,
60	0xd6990624UL, 0xf40e3585UL, 0x106aa070UL, 0x19a4c116UL, 0x1e376c08UL,
61	0x2748774cUL, 0x34b0bcb5UL, 0x391c0cb3UL, 0x4ed8aa4aUL, 0x5b9cca4fUL,
62	0x682e6ff3UL, 0x748f82eeUL, 0x78a5636fUL, 0x84c87814UL, 0x8cc70208UL,
63	0x90befffaUL, 0xa4506cebUL, 0xbef9a3f7UL, 0xc67178f2UL
64};
65
66
67/* Various logical functions */
68#define RORc(x, y) \
69( ((((unsigned long) (x) & 0xFFFFFFFFUL) >> (unsigned long) ((y) & 31)) | \
70   ((unsigned long) (x) << (unsigned long) (32 - ((y) & 31)))) & 0xFFFFFFFFUL)
71#define Ch(x,y,z)       (z ^ (x & (y ^ z)))
72#define Maj(x,y,z)      (((x | y) & z) | (x & y))
73#define S(x, n)         RORc((x), (n))
74#define R(x, n)         (((x)&0xFFFFFFFFUL)>>(n))
75#define Sigma0(x)       (S(x, 2) ^ S(x, 13) ^ S(x, 22))
76#define Sigma1(x)       (S(x, 6) ^ S(x, 11) ^ S(x, 25))
77#define Gamma0(x)       (S(x, 7) ^ S(x, 18) ^ R(x, 3))
78#define Gamma1(x)       (S(x, 17) ^ S(x, 19) ^ R(x, 10))
79#ifndef MIN
80#define MIN(x, y) (((x) < (y)) ? (x) : (y))
81#endif
82
83/* compress 512-bits */
84static int sha256_compress(struct sha256_state *md, unsigned char *buf)
85{
86	u32 S[8], W[64], t0, t1;
87	u32 t;
88	int i;
89
90	/* copy state into S */
91	for (i = 0; i < 8; i++) {
92		S[i] = md->state[i];
93	}
94
95	/* copy the state into 512-bits into W[0..15] */
96	for (i = 0; i < 16; i++)
97		W[i] = WPA_GET_BE32(buf + (4 * i));
98
99	/* fill W[16..63] */
100	for (i = 16; i < 64; i++) {
101		W[i] = Gamma1(W[i - 2]) + W[i - 7] + Gamma0(W[i - 15]) +
102			W[i - 16];
103	}
104
105	/* Compress */
106#define RND(a,b,c,d,e,f,g,h,i)                          \
107	t0 = h + Sigma1(e) + Ch(e, f, g) + K[i] + W[i];	\
108	t1 = Sigma0(a) + Maj(a, b, c);			\
109	d += t0;					\
110	h  = t0 + t1;
111
112	for (i = 0; i < 64; ++i) {
113		RND(S[0], S[1], S[2], S[3], S[4], S[5], S[6], S[7], i);
114		t = S[7]; S[7] = S[6]; S[6] = S[5]; S[5] = S[4];
115		S[4] = S[3]; S[3] = S[2]; S[2] = S[1]; S[1] = S[0]; S[0] = t;
116	}
117
118	/* feedback */
119	for (i = 0; i < 8; i++) {
120		md->state[i] = md->state[i] + S[i];
121	}
122	return 0;
123}
124
125
126/* Initialize the hash state */
127void sha256_init(struct sha256_state *md)
128{
129	md->curlen = 0;
130	md->length = 0;
131	md->state[0] = 0x6A09E667UL;
132	md->state[1] = 0xBB67AE85UL;
133	md->state[2] = 0x3C6EF372UL;
134	md->state[3] = 0xA54FF53AUL;
135	md->state[4] = 0x510E527FUL;
136	md->state[5] = 0x9B05688CUL;
137	md->state[6] = 0x1F83D9ABUL;
138	md->state[7] = 0x5BE0CD19UL;
139}
140
141/**
142   Process a block of memory though the hash
143   @param md     The hash state
144   @param in     The data to hash
145   @param inlen  The length of the data (octets)
146   @return CRYPT_OK if successful
147*/
148int sha256_process(struct sha256_state *md, const unsigned char *in,
149		   unsigned long inlen)
150{
151	unsigned long n;
152
153	if (md->curlen >= sizeof(md->buf))
154		return -1;
155
156	while (inlen > 0) {
157		if (md->curlen == 0 && inlen >= SHA256_BLOCK_SIZE) {
158			if (sha256_compress(md, (unsigned char *) in) < 0)
159				return -1;
160			md->length += SHA256_BLOCK_SIZE * 8;
161			in += SHA256_BLOCK_SIZE;
162			inlen -= SHA256_BLOCK_SIZE;
163		} else {
164			n = MIN(inlen, (SHA256_BLOCK_SIZE - md->curlen));
165			os_memcpy(md->buf + md->curlen, in, n);
166			md->curlen += n;
167			in += n;
168			inlen -= n;
169			if (md->curlen == SHA256_BLOCK_SIZE) {
170				if (sha256_compress(md, md->buf) < 0)
171					return -1;
172				md->length += 8 * SHA256_BLOCK_SIZE;
173				md->curlen = 0;
174			}
175		}
176	}
177
178	return 0;
179}
180
181
182/**
183   Terminate the hash to get the digest
184   @param md  The hash state
185   @param out [out] The destination of the hash (32 bytes)
186   @return CRYPT_OK if successful
187*/
188int sha256_done(struct sha256_state *md, unsigned char *out)
189{
190	int i;
191
192	if (md->curlen >= sizeof(md->buf))
193		return -1;
194
195	/* increase the length of the message */
196	md->length += md->curlen * 8;
197
198	/* append the '1' bit */
199	md->buf[md->curlen++] = (unsigned char) 0x80;
200
201	/* if the length is currently above 56 bytes we append zeros
202	 * then compress.  Then we can fall back to padding zeros and length
203	 * encoding like normal.
204	 */
205	if (md->curlen > 56) {
206		while (md->curlen < SHA256_BLOCK_SIZE) {
207			md->buf[md->curlen++] = (unsigned char) 0;
208		}
209		sha256_compress(md, md->buf);
210		md->curlen = 0;
211	}
212
213	/* pad up to 56 bytes of zeroes */
214	while (md->curlen < 56) {
215		md->buf[md->curlen++] = (unsigned char) 0;
216	}
217
218	/* store length */
219	WPA_PUT_BE64(md->buf + 56, md->length);
220	sha256_compress(md, md->buf);
221
222	/* copy output */
223	for (i = 0; i < 8; i++)
224		WPA_PUT_BE32(out + (4 * i), md->state[i]);
225
226	return 0;
227}
228
229/* ===== end - public domain SHA256 implementation ===== */
230