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Diffstat (limited to 'crypto/openssh/moduli.c')
| -rw-r--r-- | crypto/openssh/moduli.c | 816 | 
1 files changed, 816 insertions, 0 deletions
| diff --git a/crypto/openssh/moduli.c b/crypto/openssh/moduli.c new file mode 100644 index 000000000000..481ca2aa8ffc --- /dev/null +++ b/crypto/openssh/moduli.c @@ -0,0 +1,816 @@ +/* $OpenBSD: moduli.c,v 1.39 2023/03/02 06:41:56 dtucker 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" + +#ifdef WITH_OPENSSL + +#include <sys/types.h> + +#include <openssl/bn.h> +#include <openssl/dh.h> + +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <stdarg.h> +#include <time.h> +#include <unistd.h> +#include <limits.h> + +#include "xmalloc.h" +#include "dh.h" +#include "log.h" +#include "misc.h" + +#include "openbsd-compat/openssl-compat.h" + +/* + * File output defines + */ + +/* need line long enough for largest moduli plus headers */ +#define QLINESIZE		(100+8192) + +/* + * 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, char *, unsigned long, +    unsigned long); + +/* + * 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); +	if (gtm == NULL) +		return -1; + +	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 s32) +{ +	u_int64_t r, u, s = s32; + +	debug3("sieve_large %u", s32); +	largetries++; +	/* r = largebase mod s */ +	r = BN_mod_word(largebase, s32); +	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 * 2ULL) { +		/* +		 * 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 * 4ULL) { +		/* +		 * 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 %lld seconds", +	    ctime(&time_stop), largetries, (long 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, MODULI_TYPE_SOPHIE_GERMAIN, +		    MODULI_TESTS_SIEVE, largetries, +		    (power - 1) /* MSB */, (0), q) == -1) { +			ret = -1; +			break; +		} + +		r++; /* count q */ +	} + +	time(&time_stop); + +	free(LargeSieve); +	free(SmallSieve); +	free(TinySieve); + +	logit("%.24s Found %u candidates", ctime(&time_stop), r); + +	return (ret); +} + +static void +write_checkpoint(char *cpfile, u_int32_t lineno) +{ +	FILE *fp; +	char tmp[PATH_MAX]; +	int r, writeok, closeok; + +	r = snprintf(tmp, sizeof(tmp), "%s.XXXXXXXXXX", cpfile); +	if (r < 0 || r >= PATH_MAX) { +		logit("write_checkpoint: temp pathname too long"); +		return; +	} +	if ((r = mkstemp(tmp)) == -1) { +		logit("mkstemp(%s): %s", tmp, strerror(errno)); +		return; +	} +	if ((fp = fdopen(r, "w")) == NULL) { +		logit("write_checkpoint: fdopen: %s", strerror(errno)); +		unlink(tmp); +		close(r); +		return; +	} +	writeok = (fprintf(fp, "%lu\n", (unsigned long)lineno) > 0); +	closeok = (fclose(fp) == 0); +	if (writeok && closeok && rename(tmp, cpfile) == 0) { +		debug3("wrote checkpoint line %lu to '%s'", +		    (unsigned long)lineno, cpfile); +	} else { +		logit("failed to write to checkpoint file '%s': %s", cpfile, +		    strerror(errno)); +		(void)unlink(tmp); +	} +} + +static unsigned long +read_checkpoint(char *cpfile) +{ +	FILE *fp; +	unsigned long lineno = 0; + +	if ((fp = fopen(cpfile, "r")) == NULL) +		return 0; +	if (fscanf(fp, "%lu\n", &lineno) < 1) +		logit("Failed to load checkpoint from '%s'", cpfile); +	else +		logit("Loaded checkpoint from '%s' line %lu", cpfile, lineno); +	fclose(fp); +	return lineno; +} + +static unsigned long +count_lines(FILE *f) +{ +	unsigned long count = 0; +	char lp[QLINESIZE + 1]; + +	if (fseek(f, 0, SEEK_SET) != 0) { +		debug("input file is not seekable"); +		return ULONG_MAX; +	} +	while (fgets(lp, QLINESIZE + 1, f) != NULL) +		count++; +	rewind(f); +	debug("input file has %lu lines", count); +	return count; +} + +static char * +fmt_time(time_t seconds) +{ +	int day, hr, min; +	static char buf[128]; + +	min = (seconds / 60) % 60; +	hr = (seconds / 60 / 60) % 24; +	day = seconds / 60 / 60 / 24; +	if (day > 0) +		snprintf(buf, sizeof buf, "%dd %d:%02d", day, hr, min); +	else +		snprintf(buf, sizeof buf, "%d:%02d", hr, min); +	return buf; +} + +static void +print_progress(unsigned long start_lineno, unsigned long current_lineno, +    unsigned long end_lineno) +{ +	static time_t time_start, time_prev; +	time_t time_now, elapsed; +	unsigned long num_to_process, processed, remaining, percent, eta; +	double time_per_line; +	char *eta_str; + +	time_now = monotime(); +	if (time_start == 0) { +		time_start = time_prev = time_now; +		return; +	} +	/* print progress after 1m then once per 5m */ +	if (time_now - time_prev < 5 * 60) +		return; +	time_prev = time_now; +	elapsed = time_now - time_start; +	processed = current_lineno - start_lineno; +	remaining = end_lineno - current_lineno; +	num_to_process = end_lineno - start_lineno; +	time_per_line = (double)elapsed / processed; +	/* if we don't know how many we're processing just report count+time */ +	time(&time_now); +	if (end_lineno == ULONG_MAX) { +		logit("%.24s processed %lu in %s", ctime(&time_now), +		    processed, fmt_time(elapsed)); +		return; +	} +	percent = 100 * processed / num_to_process; +	eta = time_per_line * remaining; +	eta_str = xstrdup(fmt_time(eta)); +	logit("%.24s processed %lu of %lu (%lu%%) in %s, ETA %s", +	    ctime(&time_now), processed, num_to_process, percent, +	    fmt_time(elapsed), eta_str); +	free(eta_str); +} + +/* + * 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, +    char *checkpoint_file, unsigned long start_lineno, unsigned long num_lines) +{ +	BIGNUM *q, *p, *a; +	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; +	unsigned long last_processed = 0, end_lineno; +	time_t time_start, time_stop; +	int res, is_prime; + +	if (trials < TRIAL_MINIMUM) { +		error("Minimum primality trials is %d", TRIAL_MINIMUM); +		return (-1); +	} + +	if (num_lines == 0) +		end_lineno = count_lines(in); +	else +		end_lineno = start_lineno + num_lines; + +	time(&time_start); + +	if ((p = BN_new()) == NULL) +		fatal("BN_new failed"); +	if ((q = BN_new()) == NULL) +		fatal("BN_new failed"); + +	debug2("%.24s Final %u Miller-Rabin trials (%x generator)", +	    ctime(&time_start), trials, generator_wanted); + +	if (checkpoint_file != NULL) +		last_processed = read_checkpoint(checkpoint_file); +	last_processed = start_lineno = MAXIMUM(last_processed, start_lineno); +	if (end_lineno == ULONG_MAX) +		debug("process from line %lu from pipe", last_processed); +	else +		debug("process from line %lu to line %lu", last_processed, +		    end_lineno); + +	res = 0; +	lp = xmalloc(QLINESIZE + 1); +	while (fgets(lp, QLINESIZE + 1, in) != NULL && count_in < end_lineno) { +		count_in++; +		if (count_in <= last_processed) { +			debug3("skipping line %u, before checkpoint or " +			    "specified start line", count_in); +			continue; +		} +		if (checkpoint_file != NULL) +			write_checkpoint(checkpoint_file, count_in); +		print_progress(start_lineno, count_in, end_lineno); +		if (strlen(lp) < 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 & MODULI_TESTS_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 MODULI_TYPE_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 MODULI_TYPE_UNSTRUCTURED: +		case MODULI_TYPE_SAFE: +		case MODULI_TYPE_SCHNORR: +		case MODULI_TYPE_STRONG: +		case MODULI_TYPE_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 & MODULI_TESTS_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 { +				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. +		 */ +		is_prime = BN_is_prime_ex(q, 1, NULL, NULL); +		if (is_prime < 0) +			fatal("BN_is_prime_ex failed"); +		if (is_prime == 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. +		 */ +		is_prime = BN_is_prime_ex(p, trials, NULL, NULL); +		if (is_prime < 0) +			fatal("BN_is_prime_ex failed"); +		if (is_prime == 0) { +			debug("%10u: p is not prime", count_in); +			continue; +		} +		debug("%10u: p is almost certainly prime", count_in); + +		/* recheck q more rigorously */ +		is_prime = BN_is_prime_ex(q, trials - 1, NULL, NULL); +		if (is_prime < 0) +			fatal("BN_is_prime_ex failed"); +		if (is_prime == 0) { +			debug("%10u: q is not prime", count_in); +			continue; +		} +		debug("%10u: q is almost certainly prime", count_in); + +		if (qfileout(out, MODULI_TYPE_SAFE, +		    in_tests | MODULI_TESTS_MILLER_RABIN, +		    in_tries, in_size, generator_known, p)) { +			res = -1; +			break; +		} + +		count_out++; +	} + +	time(&time_stop); +	free(lp); +	BN_free(p); +	BN_free(q); + +	if (checkpoint_file != NULL) +		unlink(checkpoint_file); + +	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); +} + +#endif /* WITH_OPENSSL */ | 
