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63d6aac5 RZ |
1 | #include "sha256.h" |
2 | ||
3 | /** | |
4 | * SHA256 Hashing | |
5 | * @addr: pointers to the data area | |
6 | * @len: Lengths of the data block | |
7 | * @res: Buffer for the digest | |
8 | * Returns: 0 on success, -1 of failure | |
9 | */ | |
10 | int sha256(const unsigned char *addr, const size_t len, | |
11 | unsigned char *res) | |
12 | { | |
13 | struct sha256_state ctx; | |
14 | ||
15 | sha256_init(&ctx); | |
16 | ||
17 | if (sha256_process(&ctx, addr, len) || sha256_done(&ctx, res)) | |
18 | return -1; | |
19 | ||
20 | return 0; | |
21 | } | |
22 | ||
23 | /** ===== start - public domain SHA256 implementation ===== */ | |
24 | ||
25 | /** This is based on SHA256 implementation in LibTomCrypt that was released into | |
26 | * public domain by Tom St Denis. | |
27 | */ | |
28 | ||
29 | /** the K array */ | |
30 | static const unsigned long K[64] = { | |
31 | 0x428a2f98UL, 0x71374491UL, 0xb5c0fbcfUL, 0xe9b5dba5UL, 0x3956c25bUL, | |
32 | 0x59f111f1UL, 0x923f82a4UL, 0xab1c5ed5UL, 0xd807aa98UL, 0x12835b01UL, | |
33 | 0x243185beUL, 0x550c7dc3UL, 0x72be5d74UL, 0x80deb1feUL, 0x9bdc06a7UL, | |
34 | 0xc19bf174UL, 0xe49b69c1UL, 0xefbe4786UL, 0x0fc19dc6UL, 0x240ca1ccUL, | |
35 | 0x2de92c6fUL, 0x4a7484aaUL, 0x5cb0a9dcUL, 0x76f988daUL, 0x983e5152UL, | |
36 | 0xa831c66dUL, 0xb00327c8UL, 0xbf597fc7UL, 0xc6e00bf3UL, 0xd5a79147UL, | |
37 | 0x06ca6351UL, 0x14292967UL, 0x27b70a85UL, 0x2e1b2138UL, 0x4d2c6dfcUL, | |
38 | 0x53380d13UL, 0x650a7354UL, 0x766a0abbUL, 0x81c2c92eUL, 0x92722c85UL, | |
39 | 0xa2bfe8a1UL, 0xa81a664bUL, 0xc24b8b70UL, 0xc76c51a3UL, 0xd192e819UL, | |
40 | 0xd6990624UL, 0xf40e3585UL, 0x106aa070UL, 0x19a4c116UL, 0x1e376c08UL, | |
41 | 0x2748774cUL, 0x34b0bcb5UL, 0x391c0cb3UL, 0x4ed8aa4aUL, 0x5b9cca4fUL, | |
42 | 0x682e6ff3UL, 0x748f82eeUL, 0x78a5636fUL, 0x84c87814UL, 0x8cc70208UL, | |
43 | 0x90befffaUL, 0xa4506cebUL, 0xbef9a3f7UL, 0xc67178f2UL | |
44 | }; | |
45 | ||
46 | ||
47 | /** Various logical functions */ | |
48 | #define RORc(x, y) \ | |
49 | (((((unsigned long) (x) & 0xFFFFFFFFUL) >> (unsigned long) ((y) & 31)) | \ | |
50 | ((unsigned long) (x) << (unsigned long) (32 - ((y) & 31)))) & 0xFFFFFFFFUL) | |
51 | #define Ch(x, y, z) (z ^ (x & (y ^ z))) | |
52 | #define Maj(x, y, z) (((x | y) & z) | (x & y)) | |
53 | #define S(x, n) RORc((x), (n)) | |
54 | #define R(x, n) (((x)&0xFFFFFFFFUL)>>(n)) | |
55 | #define Sigma0(x) (S(x, 2) ^ S(x, 13) ^ S(x, 22)) | |
56 | #define Sigma1(x) (S(x, 6) ^ S(x, 11) ^ S(x, 25)) | |
57 | #define Gamma0(x) (S(x, 7) ^ S(x, 18) ^ R(x, 3)) | |
58 | #define Gamma1(x) (S(x, 17) ^ S(x, 19) ^ R(x, 10)) | |
59 | #ifndef MIN | |
60 | #define MIN(x, y) (((x) < (y)) ? (x) : (y)) | |
61 | #endif | |
62 | ||
63 | /* compress 512-bits */ | |
64 | static int sha256_compress(struct sha256_state *md, const unsigned char *buf) | |
65 | { | |
66 | __u32 S[8], W[64], t0, t1; | |
67 | __u32 t; | |
68 | int i; | |
69 | ||
70 | /* copy state into S */ | |
71 | for (i = 0; i < 8; i++) | |
72 | S[i] = md->state[i]; | |
73 | ||
74 | /* copy the state into 512-bits into W[0..15] */ | |
75 | for (i = 0; i < 16; i++) | |
76 | W[i] = LOAD32B(buf + (4 * i)); | |
77 | ||
78 | /* fill W[16..63] */ | |
79 | for (i = 16; i < 64; i++) | |
80 | W[i] = Gamma1(W[i - 2]) + W[i - 7] + Gamma0(W[i - 15]) + W[i - 16]; | |
81 | ||
82 | /* Compress */ | |
83 | #define RND(a, b, c, d, e, f, g, h, i) \ | |
84 | t0 = h + Sigma1(e) + Ch(e, f, g) + K[i] + W[i]; \ | |
85 | t1 = Sigma0(a) + Maj(a, b, c); \ | |
86 | d += t0; \ | |
87 | h = t0 + t1; | |
88 | ||
89 | for (i = 0; i < 64; ++i) { | |
90 | RND(S[0], S[1], S[2], S[3], S[4], S[5], S[6], S[7], i); | |
91 | t = S[7]; S[7] = S[6]; S[6] = S[5]; S[5] = S[4]; | |
92 | S[4] = S[3]; S[3] = S[2]; S[2] = S[1]; S[1] = S[0]; S[0] = t; | |
93 | } | |
94 | ||
95 | /* feedback */ | |
96 | for (i = 0; i < 8; i++) | |
97 | md->state[i] = md->state[i] + S[i]; | |
98 | ||
99 | return 0; | |
100 | } | |
101 | ||
102 | ||
103 | /* Initialize the hash state */ | |
104 | void sha256_init(struct sha256_state *md) | |
105 | { | |
106 | md->curlen = 0; | |
107 | md->length = 0; | |
108 | md->state[0] = 0x6A09E667UL; | |
109 | md->state[1] = 0xBB67AE85UL; | |
110 | md->state[2] = 0x3C6EF372UL; | |
111 | md->state[3] = 0xA54FF53AUL; | |
112 | md->state[4] = 0x510E527FUL; | |
113 | md->state[5] = 0x9B05688CUL; | |
114 | md->state[6] = 0x1F83D9ABUL; | |
115 | md->state[7] = 0x5BE0CD19UL; | |
116 | } | |
117 | ||
118 | /** | |
119 | * Process a block of memory though the hash | |
120 | * @param md The hash state | |
121 | * @param in The data to hash | |
122 | * @param inlen The length of the data (octets) | |
123 | * @return CRYPT_OK if successful | |
124 | */ | |
125 | int sha256_process(struct sha256_state *md, const unsigned char *in, | |
126 | unsigned long inlen) | |
127 | { | |
128 | unsigned long n; | |
129 | ||
130 | if (md->curlen >= sizeof(md->buf)) | |
131 | return -1; | |
132 | ||
133 | while (inlen > 0) { | |
134 | if (md->curlen == 0 && inlen >= SHA256_BLOCK_SIZE) { | |
135 | if (sha256_compress(md, (unsigned char *) in) < 0) | |
136 | return -1; | |
137 | md->length += SHA256_BLOCK_SIZE * 8; | |
138 | in += SHA256_BLOCK_SIZE; | |
139 | inlen -= SHA256_BLOCK_SIZE; | |
140 | } else { | |
141 | n = MIN(inlen, (SHA256_BLOCK_SIZE - md->curlen)); | |
142 | memcpy(md->buf + md->curlen, in, n); | |
143 | md->curlen += n; | |
144 | in += n; | |
145 | inlen -= n; | |
146 | if (md->curlen == SHA256_BLOCK_SIZE) { | |
147 | if (sha256_compress(md, md->buf) < 0) | |
148 | return -1; | |
149 | md->length += 8 * SHA256_BLOCK_SIZE; | |
150 | md->curlen = 0; | |
151 | } | |
152 | } | |
153 | } | |
154 | ||
155 | return 0; | |
156 | } | |
157 | ||
158 | ||
159 | /** | |
160 | * Terminate the hash to get the digest | |
161 | * @param md The hash state | |
162 | * @param out [out] The destination of the hash (32 bytes) | |
163 | * @return CRYPT_OK if successful | |
164 | */ | |
165 | int sha256_done(struct sha256_state *md, unsigned char *out) | |
166 | { | |
167 | int i; | |
168 | ||
169 | if (md->curlen >= sizeof(md->buf)) | |
170 | return -1; | |
171 | ||
172 | /* increase the length of the message */ | |
173 | md->length += md->curlen * 8; | |
174 | ||
175 | /* append the '1' bit */ | |
176 | md->buf[md->curlen++] = (unsigned char) 0x80; | |
177 | ||
178 | /* if the length is currently above 56 bytes we append zeros | |
179 | * then compress. Then we can fall back to padding zeros and length | |
180 | * encoding like normal. | |
181 | */ | |
182 | if (md->curlen > 56) { | |
183 | while (md->curlen < SHA256_BLOCK_SIZE) | |
184 | md->buf[md->curlen++] = (unsigned char) 0; | |
185 | ||
186 | sha256_compress(md, md->buf); | |
187 | md->curlen = 0; | |
188 | } | |
189 | ||
190 | /* pad up to 56 bytes of zeroes */ | |
191 | while (md->curlen < 56) | |
192 | md->buf[md->curlen++] = (unsigned char) 0; | |
193 | ||
194 | /* store length */ | |
195 | STORE64B(md->buf + 56, md->length); | |
196 | sha256_compress(md, md->buf); | |
197 | ||
198 | /* copy output */ | |
199 | for (i = 0; i < 8; i++) | |
200 | STORE32B(out + (4 * i), md->state[i]); | |
201 | ||
202 | return 0; | |
203 | } | |
204 | ||
205 | /* ===== end - public domain SHA256 implementation ===== */ |