2 Blind-ID library for user identification using RSA blind signatures
3 Copyright (C) 2010 Rudolf Polzer
5 This library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 This library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with this library; if not, write to the Free Software
17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20 #include "d0_bignum.h"
31 static gmp_randstate_t RANDSTATE;
32 static d0_bignum_t temp;
36 void d0_bignum_INITIALIZE(void)
39 d0_bignum_init(&temp);
40 gmp_randinit_mt(RANDSTATE);
41 gmp_randseed_ui(RANDSTATE, time(NULL));
42 f = fopen("/dev/urandom", "rb");
44 f = fopen("/dev/random", "rb");
47 unsigned char buf[256];
49 if(fread(buf, sizeof(buf), 1, f) == 1)
51 mpz_import(temp.z, sizeof(buf), 1, 1, 0, 0, buf);
52 gmp_randseed(RANDSTATE, temp.z);
58 void d0_bignum_SHUTDOWN(void)
60 d0_bignum_clear(&temp);
61 gmp_randclear(RANDSTATE);
64 BOOL d0_iobuf_write_bignum(d0_iobuf_t *buf, const d0_bignum_t *bignum)
66 static unsigned char numbuf[65536];
68 numbuf[0] = mpz_sgn(bignum->z) & 3;
69 if((numbuf[0] & 3) != 0) // nonzero
71 count = (mpz_sizeinbase(bignum->z, 2) + 7) / 8;
72 if(count > sizeof(numbuf) - 1)
74 mpz_export(numbuf+1, &count, 1, 1, 0, 0, bignum->z);
76 return d0_iobuf_write_packet(buf, numbuf, count + 1);
79 d0_bignum_t *d0_iobuf_read_bignum(d0_iobuf_t *buf, d0_bignum_t *bignum)
81 static unsigned char numbuf[65536];
82 size_t count = sizeof(numbuf);
83 if(!d0_iobuf_read_packet(buf, numbuf, &count))
87 if(!bignum) bignum = d0_bignum_new(); if(!bignum) return NULL;
88 if(numbuf[0] & 3) // nonzero
90 mpz_import(bignum->z, count-1, 1, 1, 0, 0, numbuf+1);
91 if(numbuf[0] & 2) // negative
92 mpz_neg(bignum->z, bignum->z);
96 mpz_set_ui(bignum->z, 0);
101 ssize_t d0_bignum_export_unsigned(const d0_bignum_t *bignum, void *buf, size_t bufsize)
104 count = (mpz_sizeinbase(bignum->z, 2) + 7) / 8;
109 // pad from left (big endian numbers!)
110 memset(buf, 0, bufsize - count);
111 buf += bufsize - count;
114 mpz_export(buf, &bufsize, 1, 1, 0, 0, bignum->z);
118 // mpz_sizeinbase lied to us
120 // there is no sane way whatsoever to handle this
126 // mpz_sizeinbase lied to us
130 memset(buf, 0, count);
134 memmove(buf + count - bufsize, buf, bufsize);
135 memset(buf, 0, count - bufsize);
141 d0_bignum_t *d0_bignum_import_unsigned(d0_bignum_t *bignum, const void *buf, size_t bufsize)
144 if(!bignum) bignum = d0_bignum_new(); if(!bignum) return NULL;
145 mpz_import(bignum->z, bufsize, 1, 1, 0, 0, buf);
149 d0_bignum_t *d0_bignum_new(void)
151 d0_bignum_t *b = d0_malloc(sizeof(d0_bignum_t));
156 void d0_bignum_free(d0_bignum_t *a)
162 void d0_bignum_init(d0_bignum_t *b)
167 void d0_bignum_clear(d0_bignum_t *a)
172 size_t d0_bignum_size(const d0_bignum_t *r)
174 return mpz_sizeinbase(r->z, 2);
177 int d0_bignum_cmp(const d0_bignum_t *a, const d0_bignum_t *b)
179 return mpz_cmp(a->z, b->z);
182 d0_bignum_t *d0_bignum_rand_range(d0_bignum_t *r, const d0_bignum_t *min, const d0_bignum_t *max)
184 if(!r) r = d0_bignum_new(); if(!r) return NULL;
185 mpz_sub(temp.z, max->z, min->z);
186 mpz_urandomm(r->z, RANDSTATE, temp.z);
187 mpz_add(r->z, r->z, min->z);
191 d0_bignum_t *d0_bignum_rand_bit_atmost(d0_bignum_t *r, size_t n)
193 if(!r) r = d0_bignum_new(); if(!r) return NULL;
194 mpz_urandomb(r->z, RANDSTATE, n);
198 d0_bignum_t *d0_bignum_rand_bit_exact(d0_bignum_t *r, size_t n)
200 if(!r) r = d0_bignum_new(); if(!r) return NULL;
201 mpz_urandomb(r->z, RANDSTATE, n-1);
202 mpz_setbit(r->z, n-1);
206 d0_bignum_t *d0_bignum_zero(d0_bignum_t *r)
208 return d0_bignum_int(r, 0);
211 d0_bignum_t *d0_bignum_one(d0_bignum_t *r)
213 return d0_bignum_int(r, 1);
216 d0_bignum_t *d0_bignum_int(d0_bignum_t *r, int n)
218 if(!r) r = d0_bignum_new(); if(!r) return NULL;
223 d0_bignum_t *d0_bignum_mov(d0_bignum_t *r, const d0_bignum_t *a)
227 if(!r) r = d0_bignum_new(); if(!r) return NULL;
232 d0_bignum_t *d0_bignum_neg(d0_bignum_t *r, const d0_bignum_t *a)
234 if(!r) r = d0_bignum_new(); if(!r) return NULL;
239 d0_bignum_t *d0_bignum_shl(d0_bignum_t *r, const d0_bignum_t *a, ssize_t n)
241 if(!r) r = d0_bignum_new(); if(!r) return NULL;
243 mpz_mul_2exp(r->z, a->z, n);
245 mpz_fdiv_q_2exp(r->z, a->z, -n);
251 d0_bignum_t *d0_bignum_add(d0_bignum_t *r, const d0_bignum_t *a, const d0_bignum_t *b)
253 if(!r) r = d0_bignum_new(); if(!r) return NULL;
254 mpz_add(r->z, a->z, b->z);
258 d0_bignum_t *d0_bignum_sub(d0_bignum_t *r, const d0_bignum_t *a, const d0_bignum_t *b)
260 if(!r) r = d0_bignum_new(); if(!r) return NULL;
261 mpz_sub(r->z, a->z, b->z);
265 d0_bignum_t *d0_bignum_mul(d0_bignum_t *r, const d0_bignum_t *a, const d0_bignum_t *b)
267 if(!r) r = d0_bignum_new(); if(!r) return NULL;
268 mpz_mul(r->z, a->z, b->z);
272 d0_bignum_t *d0_bignum_divmod(d0_bignum_t *q, d0_bignum_t *m, const d0_bignum_t *a, const d0_bignum_t *b)
278 mpz_fdiv_qr(q->z, m->z, a->z, b->z);
280 mpz_fdiv_q(q->z, a->z, b->z);
282 mpz_fdiv_r(m->z, a->z, b->z);
289 d0_bignum_t *d0_bignum_mod_add(d0_bignum_t *r, const d0_bignum_t *a, const d0_bignum_t *b, const d0_bignum_t *m)
291 r = d0_bignum_add(r, a, b);
292 mpz_fdiv_r(r->z, r->z, m->z);
296 d0_bignum_t *d0_bignum_mod_mul(d0_bignum_t *r, const d0_bignum_t *a, const d0_bignum_t *b, const d0_bignum_t *m)
298 r = d0_bignum_mul(r, a, b);
299 mpz_fdiv_r(r->z, r->z, m->z);
303 d0_bignum_t *d0_bignum_mod_pow(d0_bignum_t *r, const d0_bignum_t *a, const d0_bignum_t *b, const d0_bignum_t *m)
305 if(!r) r = d0_bignum_new(); if(!r) return NULL;
306 mpz_powm(r->z, a->z, b->z, m->z);
310 BOOL d0_bignum_mod_inv(d0_bignum_t *r, const d0_bignum_t *a, const d0_bignum_t *m)
312 // here, r MUST be set, as otherwise we cannot return error state!
313 return mpz_invert(r->z, a->z, m->z);
316 int d0_bignum_isprime(d0_bignum_t *r, int param)
318 return mpz_probab_prime_p(r->z, param);
321 d0_bignum_t *d0_bignum_gcd(d0_bignum_t *r, d0_bignum_t *s, d0_bignum_t *t, const d0_bignum_t *a, const d0_bignum_t *b)
323 if(!r) r = d0_bignum_new(); if(!r) return NULL;
325 mpz_gcdext(r->z, s->z, t ? t->z : NULL, a->z, b->z);
327 mpz_gcdext(r->z, t->z, NULL, b->z, a->z);
329 mpz_gcd(r->z, a->z, b->z);
333 char *d0_bignum_tostring(const d0_bignum_t *x, unsigned int base)
335 return mpz_get_str(NULL, base, x->z);