diff options
| -rw-r--r-- | internals.h | 46 | ||||
| -rw-r--r-- | smc.c | 72 | ||||
| -rw-r--r-- | smc.gp | 18 | ||||
| -rw-r--r-- | util.h | 25 |
4 files changed, 140 insertions, 21 deletions
diff --git a/internals.h b/internals.h new file mode 100644 index 0000000..32080ec --- /dev/null +++ b/internals.h @@ -0,0 +1,46 @@ +/* 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 <http://www.gnu.org/licenses/>. + */ + +/** + * @file internals.h + * @brief This header contains library internal structs. + */ + +#ifndef _BRANDT_INTERNALS_H +#define _BRANDT_INTERNALS_H + +#include <pari/pari.h> + +struct AuctionData { + GEN p; /** The "safe prime" p */ + GEN q; /** The prime @f$q = (p - 1) / 2@f$. */ + GEN g; /** The generator of @f$\mathbb{G}_q@f$ */ + uint16_t n; /** The amount of bidders/agents */ + uint16_t k; /** The amount of possible prices */ + + GEN x; /** Own private additive key share */ + GEN y; /** Own public multiplicative key share */ + GEN Y; /** Shared public key */ + + GEN m; /** Additive share of random exponents, type: Matrix(n,k) */ + GEN r; /** Key share exponent, type: Vector(k) */ + GEN b; /** Own bid, type: Vector(k) */ + + GEN alpha; /** Own alpha, type: Vector(k) */ + GEN beta; /** Own beta, type: Vector(k) */ +}; + +#endif @@ -19,27 +19,71 @@ * @brief Implementation of the smc primitives. */ +#include "util.h" + #include <pari/pari.h> GEN smc_hextodec (char *s) /* int */ { - unsigned int i, tmp; + size_t i; + char c; + pari_sp ltop = avma; GEN ret = gen_0; /* int */ - GEN v = gtovecsmall (strtoGENstr (s)); /* vecsmall */ - for (i = 1; i < lg (v); ++i) + for (i = 0; i < strlen (s); i++) { - ///TODO: scanf instead of if - if ((v[i] >= '0') && (v[i] <= '9')) - tmp = v[i] - '0'; - else if ((v[i] >= 'a') && (v[i] <= 'f')) - tmp = v[i] + 10 - 'a'; - else if ((v[i] >= 'A') && (v[i] <= 'F')) - tmp = v[i] + 10 - 'A'; - else - pari_err (e_MISC, "invalid input format"); - ret = addis (shifti (ret, 4), tmp); + 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 ret; + 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); +} + @@ -17,15 +17,19 @@ smc_hextodec(s:str) = ret; } -smc_genfield(p:int, g)= +smc_genbid(k:small, bid:small, g)= { - local(q:int); - q = (p - 1) / 2; - [Mod(g^2, p), q]; + vector(k,j,g^(bid==j)); } -smc_genkeypair(field:vec)= +smc_genalpha(k:small, b:vec, r:vec, y)= { - local(x:int=random(field[2])); - [x, field[1]^x]; + vector(k, j, b[j]*y^r[j]); } + +smc_genbeta(k:small, r:vec, g)= +{ + vector(k, j, g^r[j]); +} + + @@ -0,0 +1,25 @@ +/* This file is part of libgotr. + * (C) 2014-2015 Markus Teich, Jannik Theiß + * + * libgotr is free software; you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License as published + * by the Free Software Foundation; either version 3, or (at your + * option) any later version. + * + * libgotr 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public License + * along with libgotr; see the file LICENSE. If not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 02111-1307, USA. + */ + +#ifndef _BRANDT_UTIL_H +#define _BRANDT_UTIL_H + +void brandt_eprintf(const char *format, ...); + +#endif |