circomlib/circuit/pedersen.circom
2018-11-11 19:52:07 +01:00

48 lines
1.8 KiB
Plaintext

include "escalarmul.circom";
component Pedersen(n) {
signal input in[n];
signal output out[2];
var nexps = ((n-1) \ 253) + 1;
var nlastbits = n - (nexps-1)*253;
component escalarMuls[nexps];
var PBASE = [
[17777552123799933955779906779655732241715742912184938656739573121738514868268,
2626589144620713026669568689430873010625803728049924121243784502389097019475],
[17777552123799933955779906779655732241715742912184938656739573121738514868268,
2626589144620713026669568689430873010625803728049924121243784502389097019475],
[17777552123799933955779906779655732241715742912184938656739573121738514868268,
2626589144620713026669568689430873010625803728049924121243784502389097019475],
[17777552123799933955779906779655732241715742912184938656739573121738514868268,
2626589144620713026669568689430873010625803728049924121243784502389097019475],
[17777552123799933955779906779655732241715742912184938656739573121738514868268,
2626589144620713026669568689430873010625803728049924121243784502389097019475]
];
var i;
var j;
for (i=0; i<nexps; i++) {
var nexpbits = (i == nexps-1) ? nlastbits : 253;
escalarMuls[i] = EscalarMul(nexpbits, PBASE[i][0], PBAS[i][1]);
for (j=0; j<nexpbits; j++) {
escalarMuls[i].in[j] <== in[253*i + j];
}
if (i==0) {
escalarMuls[i].inp[0] <== 0;
escalarMuls[i].inp[1] <== 0;
} else {
escalarMuls[i].inp[0] <== escalarMuls[i-1].out[0];
escalarMuls[i].inp[1] <== escalarMuls[i-1].out[1];
}
}
escalarMuls[nexps-1].out[0] ==> out[0];
escalarMuls[nexps-1].out[1] ==> out[1];
}