1 /*	$NetBSD: sha256.c,v 1.1.1.1 2011/04/13 18:14:51 elric Exp $	*/
2 
3 /*
4  * Copyright (c) 2006 Kungliga Tekniska Högskolan
5  * (Royal Institute of Technology, Stockholm, Sweden).
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * 3. Neither the name of the Institute nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include "config.h"
37 
38 #include "hash.h"
39 #include "sha.h"
40 
41 #define Ch(x,y,z) (((x) & (y)) ^ ((~(x)) & (z)))
42 #define Maj(x,y,z) (((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z)))
43 
44 #define ROTR(x,n)   (((x)>>(n)) | ((x) << (32 - (n))))
45 
46 #define Sigma0(x)	(ROTR(x,2)  ^ ROTR(x,13) ^ ROTR(x,22))
47 #define Sigma1(x)	(ROTR(x,6)  ^ ROTR(x,11) ^ ROTR(x,25))
48 #define sigma0(x)	(ROTR(x,7)  ^ ROTR(x,18) ^ ((x)>>3))
49 #define sigma1(x)	(ROTR(x,17) ^ ROTR(x,19) ^ ((x)>>10))
50 
51 #define A m->counter[0]
52 #define B m->counter[1]
53 #define C m->counter[2]
54 #define D m->counter[3]
55 #define E m->counter[4]
56 #define F m->counter[5]
57 #define G m->counter[6]
58 #define H m->counter[7]
59 
60 static const uint32_t constant_256[64] = {
61     0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
62     0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
63     0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
64     0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
65     0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
66     0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
67     0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
68     0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
69     0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
70     0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
71     0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
72     0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
73     0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
74     0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
75     0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
76     0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
77 };
78 
79 void
80 SHA256_Init (SHA256_CTX *m)
81 {
82     m->sz[0] = 0;
83     m->sz[1] = 0;
84     A = 0x6a09e667;
85     B = 0xbb67ae85;
86     C = 0x3c6ef372;
87     D = 0xa54ff53a;
88     E = 0x510e527f;
89     F = 0x9b05688c;
90     G = 0x1f83d9ab;
91     H = 0x5be0cd19;
92 }
93 
94 static void
95 calc (SHA256_CTX *m, uint32_t *in)
96 {
97     uint32_t AA, BB, CC, DD, EE, FF, GG, HH;
98     uint32_t data[64];
99     int i;
100 
101     AA = A;
102     BB = B;
103     CC = C;
104     DD = D;
105     EE = E;
106     FF = F;
107     GG = G;
108     HH = H;
109 
110     for (i = 0; i < 16; ++i)
111 	data[i] = in[i];
112     for (i = 16; i < 64; ++i)
113 	data[i] = sigma1(data[i-2]) + data[i-7] +
114 	    sigma0(data[i-15]) + data[i - 16];
115 
116     for (i = 0; i < 64; i++) {
117 	uint32_t T1, T2;
118 
119 	T1 = HH + Sigma1(EE) + Ch(EE, FF, GG) + constant_256[i] + data[i];
120 	T2 = Sigma0(AA) + Maj(AA,BB,CC);
121 
122 	HH = GG;
123 	GG = FF;
124 	FF = EE;
125 	EE = DD + T1;
126 	DD = CC;
127 	CC = BB;
128 	BB = AA;
129 	AA = T1 + T2;
130     }
131 
132     A += AA;
133     B += BB;
134     C += CC;
135     D += DD;
136     E += EE;
137     F += FF;
138     G += GG;
139     H += HH;
140 }
141 
142 /*
143  * From `Performance analysis of MD5' by Joseph D. Touch <touch@isi.edu>
144  */
145 
146 #if !defined(WORDS_BIGENDIAN) || defined(_CRAY)
147 static inline uint32_t
148 swap_uint32_t (uint32_t t)
149 {
150 #define ROL(x,n) ((x)<<(n))|((x)>>(32-(n)))
151     uint32_t temp1, temp2;
152 
153     temp1   = cshift(t, 16);
154     temp2   = temp1 >> 8;
155     temp1  &= 0x00ff00ff;
156     temp2  &= 0x00ff00ff;
157     temp1 <<= 8;
158     return temp1 | temp2;
159 }
160 #endif
161 
162 struct x32{
163     unsigned int a:32;
164     unsigned int b:32;
165 };
166 
167 void
168 SHA256_Update (SHA256_CTX *m, const void *v, size_t len)
169 {
170     const unsigned char *p = v;
171     size_t old_sz = m->sz[0];
172     size_t offset;
173 
174     m->sz[0] += len * 8;
175     if (m->sz[0] < old_sz)
176 	++m->sz[1];
177     offset = (old_sz / 8) % 64;
178     while(len > 0){
179 	size_t l = min(len, 64 - offset);
180 	memcpy(m->save + offset, p, l);
181 	offset += l;
182 	p += l;
183 	len -= l;
184 	if(offset == 64){
185 #if !defined(WORDS_BIGENDIAN) || defined(_CRAY)
186 	    int i;
187 	    uint32_t current[16];
188 	    struct x32 *us = (struct x32*)m->save;
189 	    for(i = 0; i < 8; i++){
190 		current[2*i+0] = swap_uint32_t(us[i].a);
191 		current[2*i+1] = swap_uint32_t(us[i].b);
192 	    }
193 	    calc(m, current);
194 #else
195 	    calc(m, (uint32_t*)m->save);
196 #endif
197 	    offset = 0;
198 	}
199     }
200 }
201 
202 void
203 SHA256_Final (void *res, SHA256_CTX *m)
204 {
205     unsigned char zeros[72];
206     unsigned offset = (m->sz[0] / 8) % 64;
207     unsigned int dstart = (120 - offset - 1) % 64 + 1;
208 
209     *zeros = 0x80;
210     memset (zeros + 1, 0, sizeof(zeros) - 1);
211     zeros[dstart+7] = (m->sz[0] >> 0) & 0xff;
212     zeros[dstart+6] = (m->sz[0] >> 8) & 0xff;
213     zeros[dstart+5] = (m->sz[0] >> 16) & 0xff;
214     zeros[dstart+4] = (m->sz[0] >> 24) & 0xff;
215     zeros[dstart+3] = (m->sz[1] >> 0) & 0xff;
216     zeros[dstart+2] = (m->sz[1] >> 8) & 0xff;
217     zeros[dstart+1] = (m->sz[1] >> 16) & 0xff;
218     zeros[dstart+0] = (m->sz[1] >> 24) & 0xff;
219     SHA256_Update (m, zeros, dstart + 8);
220     {
221 	int i;
222 	unsigned char *r = (unsigned char*)res;
223 
224 	for (i = 0; i < 8; ++i) {
225 	    r[4*i+3] = m->counter[i] & 0xFF;
226 	    r[4*i+2] = (m->counter[i] >> 8) & 0xFF;
227 	    r[4*i+1] = (m->counter[i] >> 16) & 0xFF;
228 	    r[4*i]   = (m->counter[i] >> 24) & 0xFF;
229 	}
230     }
231 }
232