3 * The compression function of the sha512 hash function.
6 /* nettle, low-level cryptographics library
8 * Copyright (C) 2001, 2010 Niels Möller
10 * The nettle library is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU Lesser General Public License as published by
12 * the Free Software Foundation; either version 2.1 of the License, or (at your
13 * option) any later version.
15 * The nettle library is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
17 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
18 * License for more details.
20 * You should have received a copy of the GNU Lesser General Public License
21 * along with the nettle library; see the file COPYING.LIB. If not, write to
22 * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
38 /* A block, treated as a sequence of 64-bit words. */
39 #define SHA512_DATA_LENGTH 16
41 #define ROTR(n,x) ((x)>>(n) | ((x)<<(64-(n))))
42 #define SHR(n,x) ((x)>>(n))
44 /* The SHA512 functions. The Choice function is the same as the SHA1
45 function f1, and the majority function is the same as the SHA1 f3
46 function, and the same as for SHA256. */
48 #define Choice(x,y,z) ( (z) ^ ( (x) & ( (y) ^ (z) ) ) )
49 #define Majority(x,y,z) ( ((x) & (y)) ^ ((z) & ((x) ^ (y))) )
51 #define S0(x) (ROTR(28,(x)) ^ ROTR(34,(x)) ^ ROTR(39,(x)))
52 #define S1(x) (ROTR(14,(x)) ^ ROTR(18,(x)) ^ ROTR(41,(x)))
54 #define s0(x) (ROTR(1,(x)) ^ ROTR(8,(x)) ^ SHR(7,(x)))
55 #define s1(x) (ROTR(19,(x)) ^ ROTR(61,(x)) ^ SHR(6,(x)))
57 /* The initial expanding function. The hash function is defined over
58 an 64-word expanded input array W, where the first 16 are copies of
59 the input data, and the remaining 64 are defined by
61 W[ t ] = s1(W[t-2]) + W[t-7] + s0(W[i-15]) + W[i-16]
63 This implementation generates these values on the fly in a circular
68 ( W[(i) & 15 ] += (s1(W[((i)-2) & 15]) + W[((i)-7) & 15] + s0(W[((i)-15) & 15])) )
70 /* The prototype SHA sub-round. The fundamental sub-round is:
72 T1 = h + S1(e) + Choice(e,f,g) + K[t] + W[t]
73 T2 = S0(a) + Majority(a,b,c)
83 but this is implemented by unrolling the loop 8 times and renaming
85 ( h, a, b, c, d, e, f, g ) = ( a, b, c, d, e, f, g, h ) each
86 iteration. This code is then replicated 8, using the next 8 values
87 from the W[] array each time */
89 /* It's crucial that DATA is only used once, as that argument will
90 * have side effects. */
91 #define ROUND(a,b,c,d,e,f,g,h,k,data) do { \
92 uint64_t T = h + S1(e) + Choice(e,f,g) + k + data; \
94 h = T + S0(a) + Majority(a,b,c); \
98 _nettle_sha512_compress(uint64_t *state, const uint8_t *input, const uint64_t *k)
100 uint64_t data[SHA512_DATA_LENGTH];
101 uint64_t A, B, C, D, E, F, G, H; /* Local vars */
105 for (i = 0; i < SHA512_DATA_LENGTH; i++, input += 8)
107 data[i] = READ_UINT64(input);
110 /* Set up first buffer and local data buffer */
121 /* First 16 subrounds that act on the original data */
123 for (i = 0, d = data; i<16; i+=8, k += 8, d+= 8)
125 ROUND(A, B, C, D, E, F, G, H, k[0], d[0]);
126 ROUND(H, A, B, C, D, E, F, G, k[1], d[1]);
127 ROUND(G, H, A, B, C, D, E, F, k[2], d[2]);
128 ROUND(F, G, H, A, B, C, D, E, k[3], d[3]);
129 ROUND(E, F, G, H, A, B, C, D, k[4], d[4]);
130 ROUND(D, E, F, G, H, A, B, C, k[5], d[5]);
131 ROUND(C, D, E, F, G, H, A, B, k[6], d[6]);
132 ROUND(B, C, D, E, F, G, H, A, k[7], d[7]);
135 for (; i<80; i += 16, k+= 16)
137 ROUND(A, B, C, D, E, F, G, H, k[ 0], EXPAND(data, 0));
138 ROUND(H, A, B, C, D, E, F, G, k[ 1], EXPAND(data, 1));
139 ROUND(G, H, A, B, C, D, E, F, k[ 2], EXPAND(data, 2));
140 ROUND(F, G, H, A, B, C, D, E, k[ 3], EXPAND(data, 3));
141 ROUND(E, F, G, H, A, B, C, D, k[ 4], EXPAND(data, 4));
142 ROUND(D, E, F, G, H, A, B, C, k[ 5], EXPAND(data, 5));
143 ROUND(C, D, E, F, G, H, A, B, k[ 6], EXPAND(data, 6));
144 ROUND(B, C, D, E, F, G, H, A, k[ 7], EXPAND(data, 7));
145 ROUND(A, B, C, D, E, F, G, H, k[ 8], EXPAND(data, 8));
146 ROUND(H, A, B, C, D, E, F, G, k[ 9], EXPAND(data, 9));
147 ROUND(G, H, A, B, C, D, E, F, k[10], EXPAND(data, 10));
148 ROUND(F, G, H, A, B, C, D, E, k[11], EXPAND(data, 11));
149 ROUND(E, F, G, H, A, B, C, D, k[12], EXPAND(data, 12));
150 ROUND(D, E, F, G, H, A, B, C, k[13], EXPAND(data, 13));
151 ROUND(C, D, E, F, G, H, A, B, k[14], EXPAND(data, 14));
152 ROUND(B, C, D, E, F, G, H, A, k[15], EXPAND(data, 15));