/* This file is part of libbrandt. * Copyright (C) 2016 GNUnet e.V. * * libbrandt is free software: you can redistribute it and/or modify it under * the terms of the GNU General Public License as published by the Free Software * Foundation, either version 3 of the License, or (at your option) any later * version. * * libbrandt is distributed in the hope that it will be useful, but WITHOUT ANY * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR * A PARTICULAR PURPOSE. See the GNU General Public License for more details. * * You should have received a copy of the GNU General Public License along with * libbrandt. If not, see . */ /** * @file smc.c * @brief Implementation of the smc primitives. */ #include "util.h" #include GEN smc_hextodec (char *s) /* int */ { size_t i; char c; pari_sp ltop = avma; GEN ret = gen_0; /* int */ for (i = 0; i < strlen (s); i++) { errno = 0; if (1 != sscanf (&s[i], "%1hhx", &c)) { brandt_eprintf ("failed to parse hex (\"%s\") to decimal:", s); return NULL; } ret = addis (shifti (ret, 4), c); } return gerepilecopy (ltop, ret); } void smc_genbid (AuctionData *ad, uint16_t bid) { uint16_t j; pari_sp ltop = avma; GEN ret = cgetg (itos (ad->k)+1, t_VEC); /* vec */ for (j = 1; j <= ad->k; j++) { gel (ret, j) = gpowgs (ad->g, bid == j); } ad->b = gerepilecopy (ltop, ret); } void smc_genalpha (AuctionData *ad) { uint16_t j; pari_sp ltop = avma; GEN ret = cgetg (ad->k+1, t_VEC); for (j = 1; j <= ad->k; ++j) { gel (ret, j) = gmul (gel (ad->b, j), gpowgi (ad->y, gel (ad->r, j))); } ab->alpha = gerepilecopy (ltop, ret); } void smc_genbeta (AuctionData *ad) { uint16_t j; pari_sp ltop = avma; GEN ret = cgetg (ad->k+1, t_VEC); for (j = 1; j <= ad->k; ++j) { gel (ret, j) = gpowgi (ad->g, gel (ad->r, j)); } ab->beta = gerepilecopy (ltop, ret); }