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Diffstat (limited to 'polly/lib/External/isl/imath/examples/randprime.c')
-rw-r--r-- | polly/lib/External/isl/imath/examples/randprime.c | 245 |
1 files changed, 0 insertions, 245 deletions
diff --git a/polly/lib/External/isl/imath/examples/randprime.c b/polly/lib/External/isl/imath/examples/randprime.c deleted file mode 100644 index bca621894a3..00000000000 --- a/polly/lib/External/isl/imath/examples/randprime.c +++ /dev/null @@ -1,245 +0,0 @@ -/* - Name: randprime.c - Purpose: Generate a probable prime at random. - Author: M. J. Fromberger <http://spinning-yarns.org/michael/> - - Usage: randprime [-s] <bits> [<outfile>] - - Generate a randomly-chosen probable prime having <bits> significant bits, and - write it to the specified output file or to the standard output. If the "-s" - option is given, a prime p is chosen such that (p - 1) / 2 is also prime. - - A prime is obtained by reading random bits from /dev/random, setting the - low-order bit, and testing for primality. If the first candidate is not - prime, successive odd candidates are tried until a probable prime is found. - - Copyright (C) 2002-2008 Michael J. Fromberger, All Rights Reserved. - - Permission is hereby granted, free of charge, to any person obtaining a copy - of this software and associated documentation files (the "Software"), to deal - in the Software without restriction, including without limitation the rights - to use, copy, modify, merge, publish, distribute, sublicense, and/or sell - copies of the Software, and to permit persons to whom the Software is - furnished to do so, subject to the following conditions: - - The above copyright notice and this permission notice shall be included in - all copies or substantial portions of the Software. - - THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR - IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, - FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE - AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER - LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, - OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE - SOFTWARE. - */ - -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <errno.h> -#include <limits.h> - -#include <unistd.h> - -#include "imath.h" -#include "iprime.h" - -/* Load the specified buffer with random bytes */ -int randomize(unsigned char *buf, size_t len); - -/* Overwrite the specified value with n_bits random bits */ -mp_result mp_int_randomize(mp_int a, mp_size n_bits); - -/* Find a prime starting from the given odd seed */ -mp_result find_prime(mp_int seed, FILE *fb); -mp_result find_strong_prime(mp_int seed, FILE *fb); - -typedef mp_result (*find_f)(mp_int, FILE *); - -int main(int argc, char *argv[]) -{ - int opt, modbits; - FILE *ofp = stdout; - mp_result res; - find_f find_func = find_prime; - char tag = 'p'; - mpz_t value; - - /* Process command-line arguments */ - while((opt = getopt(argc, argv, "s")) != EOF) { - switch(opt) { - case 's': - find_func = find_strong_prime; - tag = 'P'; - break; - default: - fprintf(stderr, "Usage: randprime [-s] <bits> [<outfile>]\n"); - return 1; - } - } - - if(optind >= argc) { - fprintf(stderr, "Error: You must specify the number of significant bits.\n"); - fprintf(stderr, "Usage: randprime [-s] <bits> [<outfile>]\n"); - return 1; - } - modbits = (int) strtol(argv[optind++], NULL, 0); - if(modbits < CHAR_BIT) { - fprintf(stderr, "Error: Invalid value for number of significant bits.\n"); - return 1; - } - if(modbits % 2 == 1) - ++modbits; - - /* Check if output file is specified */ - if(optind < argc) { - if((ofp = fopen(argv[optind], "wt")) == NULL) { - fprintf(stderr, "Error: Unable to open output file for writing.\n" - " - Filename: %s\n" - " - Error: %s\n", argv[optind], strerror(errno)); - return 1; - } - } - - mp_int_init(&value); - if ((res = mp_int_randomize(&value, modbits - 1)) != MP_OK) { - fprintf(stderr, "Error: Unable to generate random start value.\n" - " - %s (%d)\n", mp_error_string(res), res); - goto EXIT; - } - fprintf(stderr, "%c: ", tag); - find_func(&value, stderr); - fputc('\n', stderr); - - /* Write the completed value to the specified output file */ - { - int len; - char *obuf; - - len = mp_int_string_len(&value, 10); - obuf = malloc(len); - mp_int_to_string(&value, 10, obuf, len); - fputs(obuf, ofp); - fputc('\n', ofp); - - free(obuf); - } - - EXIT: - fclose(ofp); - mp_int_clear(&value); - return 0; -} - -int randomize(unsigned char *buf, size_t len) -{ - FILE *rnd = fopen("/dev/random", "rb"); - size_t nr; - - if(rnd == NULL) - return -1; - - nr = fread(buf, sizeof(*buf), len, rnd); - fclose(rnd); - - return (int) nr; -} - -mp_result mp_int_randomize(mp_int a, mp_size n_bits) -{ - mp_size n_bytes = (n_bits + CHAR_BIT - 1) / CHAR_BIT; - unsigned char *buf; - mp_result res = MP_OK; - - if((buf = malloc(n_bytes)) == NULL) - return MP_MEMORY; - - if(randomize(buf, n_bytes) != n_bytes) { - res = MP_TRUNC; - goto CLEANUP; - } - - /* Clear bits beyond the number requested */ - if(n_bits % CHAR_BIT != 0) { - unsigned char b_mask = (1 << (n_bits % CHAR_BIT)) - 1; - unsigned char t_mask = (1 << (n_bits % CHAR_BIT)) >> 1; - - buf[0] &= b_mask; - buf[0] |= t_mask; - } - - /* Set low-order bit to insure value is odd */ - buf[n_bytes - 1] |= 1; - - res = mp_int_read_unsigned(a, buf, n_bytes); - - CLEANUP: - memset(buf, 0, n_bytes); - free(buf); - - return res; -} - -mp_result find_prime(mp_int seed, FILE *fb) -{ - mp_result res; - int count = 0; - - if(mp_int_is_even(seed)) - if((res = mp_int_add_value(seed, 1, seed)) != MP_OK) - return res; - - while((res = mp_int_is_prime(seed)) == MP_FALSE) { - ++count; - - if(fb != NULL && (count % 50) == 0) - fputc('.', fb); - - if((res = mp_int_add_value(seed, 2, seed)) != MP_OK) - return res; - } - - if(res == MP_TRUE && fb != NULL) - fputc('+', fb); - - return res; -} - -mp_result find_strong_prime(mp_int seed, FILE *fb) -{ - mp_result res; - mpz_t t; - - mp_int_init(&t); - for(;;) { - if ((res = find_prime(seed, fb)) != MP_TRUE) - break; - if ((res = mp_int_copy(seed, &t)) != MP_OK) - break; - - if ((res = mp_int_mul_pow2(&t, 1, &t)) != MP_OK || - (res = mp_int_add_value(&t, 1, &t)) != MP_OK) - break; - - if ((res = mp_int_is_prime(&t)) == MP_TRUE) { - if (fb != NULL) - fputc('!', fb); - - res = mp_int_copy(&t, seed); - break; - } - else if (res != MP_FALSE) - break; - - if (fb != NULL) - fputc('x', fb); - if ((res = mp_int_add_value(seed, 2, seed)) != MP_OK) - break; - } - - mp_int_clear(&t); - return res; -} - -/* Here there be dragons */ |