diff options
author | des <des@FreeBSD.org> | 2008-07-22 17:13:05 +0000 |
---|---|---|
committer | des <des@FreeBSD.org> | 2008-07-22 17:13:05 +0000 |
commit | 624d93001f28e236c027516d88282351eb7bffbe (patch) | |
tree | 4b825dc642cb6eb9a060e54bf8d69288fbee4904 /crypto/openssh/moduli.c | |
parent | f591b3e29c677bff2b0f0d482490554c419128fd (diff) | |
download | FreeBSD-src-624d93001f28e236c027516d88282351eb7bffbe.zip FreeBSD-src-624d93001f28e236c027516d88282351eb7bffbe.tar.gz |
Flatten the OpenSSH vendor tree for 3.x and newer.
Diffstat (limited to 'crypto/openssh/moduli.c')
-rw-r--r-- | crypto/openssh/moduli.c | 669 |
1 files changed, 0 insertions, 669 deletions
diff --git a/crypto/openssh/moduli.c b/crypto/openssh/moduli.c deleted file mode 100644 index 44e5ddf..0000000 --- a/crypto/openssh/moduli.c +++ /dev/null @@ -1,669 +0,0 @@ -/* $OpenBSD: moduli.c,v 1.19 2006/11/06 21:25:28 markus Exp $ */ -/* - * Copyright 1994 Phil Karn <karn@qualcomm.com> - * Copyright 1996-1998, 2003 William Allen Simpson <wsimpson@greendragon.com> - * Copyright 2000 Niels Provos <provos@citi.umich.edu> - * All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * - * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR - * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES - * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. - * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, - * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT - * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, - * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY - * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT - * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF - * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - */ - -/* - * Two-step process to generate safe primes for DHGEX - * - * Sieve candidates for "safe" primes, - * suitable for use as Diffie-Hellman moduli; - * that is, where q = (p-1)/2 is also prime. - * - * First step: generate candidate primes (memory intensive) - * Second step: test primes' safety (processor intensive) - */ - -#include "includes.h" - -#include <sys/types.h> - -#include <openssl/bn.h> - -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <stdarg.h> -#include <time.h> - -#include "xmalloc.h" -#include "log.h" - -/* - * File output defines - */ - -/* need line long enough for largest moduli plus headers */ -#define QLINESIZE (100+8192) - -/* Type: decimal. - * Specifies the internal structure of the prime modulus. - */ -#define QTYPE_UNKNOWN (0) -#define QTYPE_UNSTRUCTURED (1) -#define QTYPE_SAFE (2) -#define QTYPE_SCHNORR (3) -#define QTYPE_SOPHIE_GERMAIN (4) -#define QTYPE_STRONG (5) - -/* Tests: decimal (bit field). - * Specifies the methods used in checking for primality. - * Usually, more than one test is used. - */ -#define QTEST_UNTESTED (0x00) -#define QTEST_COMPOSITE (0x01) -#define QTEST_SIEVE (0x02) -#define QTEST_MILLER_RABIN (0x04) -#define QTEST_JACOBI (0x08) -#define QTEST_ELLIPTIC (0x10) - -/* - * Size: decimal. - * Specifies the number of the most significant bit (0 to M). - * WARNING: internally, usually 1 to N. - */ -#define QSIZE_MINIMUM (511) - -/* - * Prime sieving defines - */ - -/* Constant: assuming 8 bit bytes and 32 bit words */ -#define SHIFT_BIT (3) -#define SHIFT_BYTE (2) -#define SHIFT_WORD (SHIFT_BIT+SHIFT_BYTE) -#define SHIFT_MEGABYTE (20) -#define SHIFT_MEGAWORD (SHIFT_MEGABYTE-SHIFT_BYTE) - -/* - * Using virtual memory can cause thrashing. This should be the largest - * number that is supported without a large amount of disk activity -- - * that would increase the run time from hours to days or weeks! - */ -#define LARGE_MINIMUM (8UL) /* megabytes */ - -/* - * Do not increase this number beyond the unsigned integer bit size. - * Due to a multiple of 4, it must be LESS than 128 (yielding 2**30 bits). - */ -#define LARGE_MAXIMUM (127UL) /* megabytes */ - -/* - * Constant: when used with 32-bit integers, the largest sieve prime - * has to be less than 2**32. - */ -#define SMALL_MAXIMUM (0xffffffffUL) - -/* Constant: can sieve all primes less than 2**32, as 65537**2 > 2**32-1. */ -#define TINY_NUMBER (1UL<<16) - -/* Ensure enough bit space for testing 2*q. */ -#define TEST_MAXIMUM (1UL<<16) -#define TEST_MINIMUM (QSIZE_MINIMUM + 1) -/* real TEST_MINIMUM (1UL << (SHIFT_WORD - TEST_POWER)) */ -#define TEST_POWER (3) /* 2**n, n < SHIFT_WORD */ - -/* bit operations on 32-bit words */ -#define BIT_CLEAR(a,n) ((a)[(n)>>SHIFT_WORD] &= ~(1L << ((n) & 31))) -#define BIT_SET(a,n) ((a)[(n)>>SHIFT_WORD] |= (1L << ((n) & 31))) -#define BIT_TEST(a,n) ((a)[(n)>>SHIFT_WORD] & (1L << ((n) & 31))) - -/* - * Prime testing defines - */ - -/* Minimum number of primality tests to perform */ -#define TRIAL_MINIMUM (4) - -/* - * Sieving data (XXX - move to struct) - */ - -/* sieve 2**16 */ -static u_int32_t *TinySieve, tinybits; - -/* sieve 2**30 in 2**16 parts */ -static u_int32_t *SmallSieve, smallbits, smallbase; - -/* sieve relative to the initial value */ -static u_int32_t *LargeSieve, largewords, largetries, largenumbers; -static u_int32_t largebits, largememory; /* megabytes */ -static BIGNUM *largebase; - -int gen_candidates(FILE *, u_int32_t, u_int32_t, BIGNUM *); -int prime_test(FILE *, FILE *, u_int32_t, u_int32_t); - -/* - * print moduli out in consistent form, - */ -static int -qfileout(FILE * ofile, u_int32_t otype, u_int32_t otests, u_int32_t otries, - u_int32_t osize, u_int32_t ogenerator, BIGNUM * omodulus) -{ - struct tm *gtm; - time_t time_now; - int res; - - time(&time_now); - gtm = gmtime(&time_now); - - res = fprintf(ofile, "%04d%02d%02d%02d%02d%02d %u %u %u %u %x ", - gtm->tm_year + 1900, gtm->tm_mon + 1, gtm->tm_mday, - gtm->tm_hour, gtm->tm_min, gtm->tm_sec, - otype, otests, otries, osize, ogenerator); - - if (res < 0) - return (-1); - - if (BN_print_fp(ofile, omodulus) < 1) - return (-1); - - res = fprintf(ofile, "\n"); - fflush(ofile); - - return (res > 0 ? 0 : -1); -} - - -/* - ** Sieve p's and q's with small factors - */ -static void -sieve_large(u_int32_t s) -{ - u_int32_t r, u; - - debug3("sieve_large %u", s); - largetries++; - /* r = largebase mod s */ - r = BN_mod_word(largebase, s); - if (r == 0) - u = 0; /* s divides into largebase exactly */ - else - u = s - r; /* largebase+u is first entry divisible by s */ - - if (u < largebits * 2) { - /* - * The sieve omits p's and q's divisible by 2, so ensure that - * largebase+u is odd. Then, step through the sieve in - * increments of 2*s - */ - if (u & 0x1) - u += s; /* Make largebase+u odd, and u even */ - - /* Mark all multiples of 2*s */ - for (u /= 2; u < largebits; u += s) - BIT_SET(LargeSieve, u); - } - - /* r = p mod s */ - r = (2 * r + 1) % s; - if (r == 0) - u = 0; /* s divides p exactly */ - else - u = s - r; /* p+u is first entry divisible by s */ - - if (u < largebits * 4) { - /* - * The sieve omits p's divisible by 4, so ensure that - * largebase+u is not. Then, step through the sieve in - * increments of 4*s - */ - while (u & 0x3) { - if (SMALL_MAXIMUM - u < s) - return; - u += s; - } - - /* Mark all multiples of 4*s */ - for (u /= 4; u < largebits; u += s) - BIT_SET(LargeSieve, u); - } -} - -/* - * list candidates for Sophie-Germain primes (where q = (p-1)/2) - * to standard output. - * The list is checked against small known primes (less than 2**30). - */ -int -gen_candidates(FILE *out, u_int32_t memory, u_int32_t power, BIGNUM *start) -{ - BIGNUM *q; - u_int32_t j, r, s, t; - u_int32_t smallwords = TINY_NUMBER >> 6; - u_int32_t tinywords = TINY_NUMBER >> 6; - time_t time_start, time_stop; - u_int32_t i; - int ret = 0; - - largememory = memory; - - if (memory != 0 && - (memory < LARGE_MINIMUM || memory > LARGE_MAXIMUM)) { - error("Invalid memory amount (min %ld, max %ld)", - LARGE_MINIMUM, LARGE_MAXIMUM); - return (-1); - } - - /* - * Set power to the length in bits of the prime to be generated. - * This is changed to 1 less than the desired safe prime moduli p. - */ - if (power > TEST_MAXIMUM) { - error("Too many bits: %u > %lu", power, TEST_MAXIMUM); - return (-1); - } else if (power < TEST_MINIMUM) { - error("Too few bits: %u < %u", power, TEST_MINIMUM); - return (-1); - } - power--; /* decrement before squaring */ - - /* - * The density of ordinary primes is on the order of 1/bits, so the - * density of safe primes should be about (1/bits)**2. Set test range - * to something well above bits**2 to be reasonably sure (but not - * guaranteed) of catching at least one safe prime. - */ - largewords = ((power * power) >> (SHIFT_WORD - TEST_POWER)); - - /* - * Need idea of how much memory is available. We don't have to use all - * of it. - */ - if (largememory > LARGE_MAXIMUM) { - logit("Limited memory: %u MB; limit %lu MB", - largememory, LARGE_MAXIMUM); - largememory = LARGE_MAXIMUM; - } - - if (largewords <= (largememory << SHIFT_MEGAWORD)) { - logit("Increased memory: %u MB; need %u bytes", - largememory, (largewords << SHIFT_BYTE)); - largewords = (largememory << SHIFT_MEGAWORD); - } else if (largememory > 0) { - logit("Decreased memory: %u MB; want %u bytes", - largememory, (largewords << SHIFT_BYTE)); - largewords = (largememory << SHIFT_MEGAWORD); - } - - TinySieve = xcalloc(tinywords, sizeof(u_int32_t)); - tinybits = tinywords << SHIFT_WORD; - - SmallSieve = xcalloc(smallwords, sizeof(u_int32_t)); - smallbits = smallwords << SHIFT_WORD; - - /* - * dynamically determine available memory - */ - while ((LargeSieve = calloc(largewords, sizeof(u_int32_t))) == NULL) - largewords -= (1L << (SHIFT_MEGAWORD - 2)); /* 1/4 MB chunks */ - - largebits = largewords << SHIFT_WORD; - largenumbers = largebits * 2; /* even numbers excluded */ - - /* validation check: count the number of primes tried */ - largetries = 0; - if ((q = BN_new()) == NULL) - fatal("BN_new failed"); - - /* - * Generate random starting point for subprime search, or use - * specified parameter. - */ - if ((largebase = BN_new()) == NULL) - fatal("BN_new failed"); - if (start == NULL) { - if (BN_rand(largebase, power, 1, 1) == 0) - fatal("BN_rand failed"); - } else { - if (BN_copy(largebase, start) == NULL) - fatal("BN_copy: failed"); - } - - /* ensure odd */ - if (BN_set_bit(largebase, 0) == 0) - fatal("BN_set_bit: failed"); - - time(&time_start); - - logit("%.24s Sieve next %u plus %u-bit", ctime(&time_start), - largenumbers, power); - debug2("start point: 0x%s", BN_bn2hex(largebase)); - - /* - * TinySieve - */ - for (i = 0; i < tinybits; i++) { - if (BIT_TEST(TinySieve, i)) - continue; /* 2*i+3 is composite */ - - /* The next tiny prime */ - t = 2 * i + 3; - - /* Mark all multiples of t */ - for (j = i + t; j < tinybits; j += t) - BIT_SET(TinySieve, j); - - sieve_large(t); - } - - /* - * Start the small block search at the next possible prime. To avoid - * fencepost errors, the last pass is skipped. - */ - for (smallbase = TINY_NUMBER + 3; - smallbase < (SMALL_MAXIMUM - TINY_NUMBER); - smallbase += TINY_NUMBER) { - for (i = 0; i < tinybits; i++) { - if (BIT_TEST(TinySieve, i)) - continue; /* 2*i+3 is composite */ - - /* The next tiny prime */ - t = 2 * i + 3; - r = smallbase % t; - - if (r == 0) { - s = 0; /* t divides into smallbase exactly */ - } else { - /* smallbase+s is first entry divisible by t */ - s = t - r; - } - - /* - * The sieve omits even numbers, so ensure that - * smallbase+s is odd. Then, step through the sieve - * in increments of 2*t - */ - if (s & 1) - s += t; /* Make smallbase+s odd, and s even */ - - /* Mark all multiples of 2*t */ - for (s /= 2; s < smallbits; s += t) - BIT_SET(SmallSieve, s); - } - - /* - * SmallSieve - */ - for (i = 0; i < smallbits; i++) { - if (BIT_TEST(SmallSieve, i)) - continue; /* 2*i+smallbase is composite */ - - /* The next small prime */ - sieve_large((2 * i) + smallbase); - } - - memset(SmallSieve, 0, smallwords << SHIFT_BYTE); - } - - time(&time_stop); - - logit("%.24s Sieved with %u small primes in %ld seconds", - ctime(&time_stop), largetries, (long) (time_stop - time_start)); - - for (j = r = 0; j < largebits; j++) { - if (BIT_TEST(LargeSieve, j)) - continue; /* Definitely composite, skip */ - - debug2("test q = largebase+%u", 2 * j); - if (BN_set_word(q, 2 * j) == 0) - fatal("BN_set_word failed"); - if (BN_add(q, q, largebase) == 0) - fatal("BN_add failed"); - if (qfileout(out, QTYPE_SOPHIE_GERMAIN, QTEST_SIEVE, - largetries, (power - 1) /* MSB */, (0), q) == -1) { - ret = -1; - break; - } - - r++; /* count q */ - } - - time(&time_stop); - - xfree(LargeSieve); - xfree(SmallSieve); - xfree(TinySieve); - - logit("%.24s Found %u candidates", ctime(&time_stop), r); - - return (ret); -} - -/* - * perform a Miller-Rabin primality test - * on the list of candidates - * (checking both q and p) - * The result is a list of so-call "safe" primes - */ -int -prime_test(FILE *in, FILE *out, u_int32_t trials, u_int32_t generator_wanted) -{ - BIGNUM *q, *p, *a; - BN_CTX *ctx; - char *cp, *lp; - u_int32_t count_in = 0, count_out = 0, count_possible = 0; - u_int32_t generator_known, in_tests, in_tries, in_type, in_size; - time_t time_start, time_stop; - int res; - - if (trials < TRIAL_MINIMUM) { - error("Minimum primality trials is %d", TRIAL_MINIMUM); - return (-1); - } - - time(&time_start); - - if ((p = BN_new()) == NULL) - fatal("BN_new failed"); - if ((q = BN_new()) == NULL) - fatal("BN_new failed"); - if ((ctx = BN_CTX_new()) == NULL) - fatal("BN_CTX_new failed"); - - debug2("%.24s Final %u Miller-Rabin trials (%x generator)", - ctime(&time_start), trials, generator_wanted); - - res = 0; - lp = xmalloc(QLINESIZE + 1); - while (fgets(lp, QLINESIZE, in) != NULL) { - int ll = strlen(lp); - - count_in++; - if (ll < 14 || *lp == '!' || *lp == '#') { - debug2("%10u: comment or short line", count_in); - continue; - } - - /* XXX - fragile parser */ - /* time */ - cp = &lp[14]; /* (skip) */ - - /* type */ - in_type = strtoul(cp, &cp, 10); - - /* tests */ - in_tests = strtoul(cp, &cp, 10); - - if (in_tests & QTEST_COMPOSITE) { - debug2("%10u: known composite", count_in); - continue; - } - - /* tries */ - in_tries = strtoul(cp, &cp, 10); - - /* size (most significant bit) */ - in_size = strtoul(cp, &cp, 10); - - /* generator (hex) */ - generator_known = strtoul(cp, &cp, 16); - - /* Skip white space */ - cp += strspn(cp, " "); - - /* modulus (hex) */ - switch (in_type) { - case QTYPE_SOPHIE_GERMAIN: - debug2("%10u: (%u) Sophie-Germain", count_in, in_type); - a = q; - if (BN_hex2bn(&a, cp) == 0) - fatal("BN_hex2bn failed"); - /* p = 2*q + 1 */ - if (BN_lshift(p, q, 1) == 0) - fatal("BN_lshift failed"); - if (BN_add_word(p, 1) == 0) - fatal("BN_add_word failed"); - in_size += 1; - generator_known = 0; - break; - case QTYPE_UNSTRUCTURED: - case QTYPE_SAFE: - case QTYPE_SCHNORR: - case QTYPE_STRONG: - case QTYPE_UNKNOWN: - debug2("%10u: (%u)", count_in, in_type); - a = p; - if (BN_hex2bn(&a, cp) == 0) - fatal("BN_hex2bn failed"); - /* q = (p-1) / 2 */ - if (BN_rshift(q, p, 1) == 0) - fatal("BN_rshift failed"); - break; - default: - debug2("Unknown prime type"); - break; - } - - /* - * due to earlier inconsistencies in interpretation, check - * the proposed bit size. - */ - if ((u_int32_t)BN_num_bits(p) != (in_size + 1)) { - debug2("%10u: bit size %u mismatch", count_in, in_size); - continue; - } - if (in_size < QSIZE_MINIMUM) { - debug2("%10u: bit size %u too short", count_in, in_size); - continue; - } - - if (in_tests & QTEST_MILLER_RABIN) - in_tries += trials; - else - in_tries = trials; - - /* - * guess unknown generator - */ - if (generator_known == 0) { - if (BN_mod_word(p, 24) == 11) - generator_known = 2; - else if (BN_mod_word(p, 12) == 5) - generator_known = 3; - else { - u_int32_t r = BN_mod_word(p, 10); - - if (r == 3 || r == 7) - generator_known = 5; - } - } - /* - * skip tests when desired generator doesn't match - */ - if (generator_wanted > 0 && - generator_wanted != generator_known) { - debug2("%10u: generator %d != %d", - count_in, generator_known, generator_wanted); - continue; - } - - /* - * Primes with no known generator are useless for DH, so - * skip those. - */ - if (generator_known == 0) { - debug2("%10u: no known generator", count_in); - continue; - } - - count_possible++; - - /* - * The (1/4)^N performance bound on Miller-Rabin is - * extremely pessimistic, so don't spend a lot of time - * really verifying that q is prime until after we know - * that p is also prime. A single pass will weed out the - * vast majority of composite q's. - */ - if (BN_is_prime(q, 1, NULL, ctx, NULL) <= 0) { - debug("%10u: q failed first possible prime test", - count_in); - continue; - } - - /* - * q is possibly prime, so go ahead and really make sure - * that p is prime. If it is, then we can go back and do - * the same for q. If p is composite, chances are that - * will show up on the first Rabin-Miller iteration so it - * doesn't hurt to specify a high iteration count. - */ - if (!BN_is_prime(p, trials, NULL, ctx, NULL)) { - debug("%10u: p is not prime", count_in); - continue; - } - debug("%10u: p is almost certainly prime", count_in); - - /* recheck q more rigorously */ - if (!BN_is_prime(q, trials - 1, NULL, ctx, NULL)) { - debug("%10u: q is not prime", count_in); - continue; - } - debug("%10u: q is almost certainly prime", count_in); - - if (qfileout(out, QTYPE_SAFE, (in_tests | QTEST_MILLER_RABIN), - in_tries, in_size, generator_known, p)) { - res = -1; - break; - } - - count_out++; - } - - time(&time_stop); - xfree(lp); - BN_free(p); - BN_free(q); - BN_CTX_free(ctx); - - logit("%.24s Found %u safe primes of %u candidates in %ld seconds", - ctime(&time_stop), count_out, count_possible, - (long) (time_stop - time_start)); - - return (res); -} |