1/*
 2    Copyright 2018 0KIMS association.
 3
 4    This file is part of circom (Zero Knowledge Circuit Compiler).
 5
 6    circom is a free software: you can redistribute it and/or modify it
 7    under the terms of the GNU General Public License as published by
 8    the Free Software Foundation, either version 3 of the License, or
 9    (at your option) any later version.
10
11    circom is distributed in the hope that it will be useful, but WITHOUT
12    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
13    or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
14    License for more details.
15
16    You should have received a copy of the GNU General Public License
17    along with circom. If not, see <https://www.gnu.org/licenses/>.
18*/
19
20include "constants.circom";
21include "sha256compression.circom";
22include "../bitify.circom"
23
24template Sha256_2() {
25    signal input a;
26    signal input b;
27    signal output out;
28
29    var i;
30    var k;
31
32    component bits2num = Bits2Num(216);
33    component num2bits[2];
34
35    num2bits[0] = Num2Bits(216);
36    num2bits[1] = Num2Bits(216);
37
38    num2bits[0].in <== a;
39    num2bits[1].in <== b;
40
41
42    component sha256compression = Sha256compression() ;
43
44    component ha0 = H(0);
45    component hb0 = H(1);
46    component hc0 = H(2);
47    component hd0 = H(3);
48    component he0 = H(4);
49    component hf0 = H(5);
50    component hg0 = H(6);
51    component hh0 = H(7);
52
53    for (k=0; k<32; k++ ) {
54        sha256compression.hin[0*32+k] <== ha0.out[k];
55        sha256compression.hin[1*32+k] <== hb0.out[k];
56        sha256compression.hin[2*32+k] <== hc0.out[k];
57        sha256compression.hin[3*32+k] <== hd0.out[k];
58        sha256compression.hin[4*32+k] <== he0.out[k];
59        sha256compression.hin[5*32+k] <== hf0.out[k];
60        sha256compression.hin[6*32+k] <== hg0.out[k];
61        sha256compression.hin[7*32+k] <== hh0.out[k];
62    }
63
64    for (i=0; i<216; i++) {
65        sha256compression.inp[i] <== num2bits[0].out[215-i];
66        sha256compression.inp[i+216] <== num2bits[1].out[215-i];
67    }
68
69    sha256compression.inp[432] <== 1;
70
71    for (i=433; i<503; i++) {
72        sha256compression.inp[i] <== 0;
73    }
74
75    sha256compression.inp[503] <== 1;
76    sha256compression.inp[504] <== 1;
77    sha256compression.inp[505] <== 0;
78    sha256compression.inp[506] <== 1;
79    sha256compression.inp[507] <== 1;
80    sha256compression.inp[508] <== 0;
81    sha256compression.inp[509] <== 0;
82    sha256compression.inp[510] <== 0;
83    sha256compression.inp[511] <== 0;
84
85    for (i=0; i<216; i++) {
86        bits2num.in[i] <== sha256compression.out[255-i];
87    }
88
89    out <== bits2num.out;
90}