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