Annotation of src/usr.bin/ssh/moduli.c, Revision 1.39
1.39 ! dtucker 1: /* $OpenBSD: moduli.c,v 1.38 2022/05/01 23:20:30 djm Exp $ */
1.1 djm 2: /*
3: * Copyright 1994 Phil Karn <karn@qualcomm.com>
4: * Copyright 1996-1998, 2003 William Allen Simpson <wsimpson@greendragon.com>
5: * Copyright 2000 Niels Provos <provos@citi.umich.edu>
6: * All rights reserved.
7: *
8: * Redistribution and use in source and binary forms, with or without
9: * modification, are permitted provided that the following conditions
10: * are met:
11: * 1. Redistributions of source code must retain the above copyright
12: * notice, this list of conditions and the following disclaimer.
13: * 2. Redistributions in binary form must reproduce the above copyright
14: * notice, this list of conditions and the following disclaimer in the
15: * documentation and/or other materials provided with the distribution.
16: *
17: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27: */
28:
29: /*
30: * Two-step process to generate safe primes for DHGEX
31: *
32: * Sieve candidates for "safe" primes,
33: * suitable for use as Diffie-Hellman moduli;
34: * that is, where q = (p-1)/2 is also prime.
35: *
36: * First step: generate candidate primes (memory intensive)
37: * Second step: test primes' safety (processor intensive)
38: */
39:
1.14 stevesk 40: #include <sys/types.h>
41:
42: #include <openssl/bn.h>
1.21 djm 43: #include <openssl/dh.h>
1.14 stevesk 44:
1.24 stsp 45: #include <errno.h>
1.17 stevesk 46: #include <stdio.h>
1.16 stevesk 47: #include <stdlib.h>
1.15 stevesk 48: #include <string.h>
1.18 deraadt 49: #include <stdarg.h>
1.14 stevesk 50: #include <time.h>
1.23 dtucker 51: #include <unistd.h>
1.30 deraadt 52: #include <limits.h>
1.14 stevesk 53:
1.1 djm 54: #include "xmalloc.h"
1.21 djm 55: #include "dh.h"
1.1 djm 56: #include "log.h"
1.28 dtucker 57: #include "misc.h"
1.1 djm 58:
59: /*
60: * File output defines
61: */
62:
63: /* need line long enough for largest moduli plus headers */
1.9 deraadt 64: #define QLINESIZE (100+8192)
1.1 djm 65:
1.5 djm 66: /*
67: * Size: decimal.
1.1 djm 68: * Specifies the number of the most significant bit (0 to M).
1.5 djm 69: * WARNING: internally, usually 1 to N.
1.1 djm 70: */
1.9 deraadt 71: #define QSIZE_MINIMUM (511)
1.1 djm 72:
73: /*
74: * Prime sieving defines
75: */
76:
77: /* Constant: assuming 8 bit bytes and 32 bit words */
1.9 deraadt 78: #define SHIFT_BIT (3)
79: #define SHIFT_BYTE (2)
80: #define SHIFT_WORD (SHIFT_BIT+SHIFT_BYTE)
81: #define SHIFT_MEGABYTE (20)
82: #define SHIFT_MEGAWORD (SHIFT_MEGABYTE-SHIFT_BYTE)
1.1 djm 83:
84: /*
1.7 djm 85: * Using virtual memory can cause thrashing. This should be the largest
86: * number that is supported without a large amount of disk activity --
87: * that would increase the run time from hours to days or weeks!
88: */
1.9 deraadt 89: #define LARGE_MINIMUM (8UL) /* megabytes */
1.7 djm 90:
91: /*
92: * Do not increase this number beyond the unsigned integer bit size.
93: * Due to a multiple of 4, it must be LESS than 128 (yielding 2**30 bits).
94: */
1.9 deraadt 95: #define LARGE_MAXIMUM (127UL) /* megabytes */
1.7 djm 96:
97: /*
1.1 djm 98: * Constant: when used with 32-bit integers, the largest sieve prime
99: * has to be less than 2**32.
100: */
1.9 deraadt 101: #define SMALL_MAXIMUM (0xffffffffUL)
1.1 djm 102:
103: /* Constant: can sieve all primes less than 2**32, as 65537**2 > 2**32-1. */
1.9 deraadt 104: #define TINY_NUMBER (1UL<<16)
1.1 djm 105:
106: /* Ensure enough bit space for testing 2*q. */
1.12 djm 107: #define TEST_MAXIMUM (1UL<<16)
108: #define TEST_MINIMUM (QSIZE_MINIMUM + 1)
109: /* real TEST_MINIMUM (1UL << (SHIFT_WORD - TEST_POWER)) */
110: #define TEST_POWER (3) /* 2**n, n < SHIFT_WORD */
1.1 djm 111:
112: /* bit operations on 32-bit words */
1.12 djm 113: #define BIT_CLEAR(a,n) ((a)[(n)>>SHIFT_WORD] &= ~(1L << ((n) & 31)))
114: #define BIT_SET(a,n) ((a)[(n)>>SHIFT_WORD] |= (1L << ((n) & 31)))
115: #define BIT_TEST(a,n) ((a)[(n)>>SHIFT_WORD] & (1L << ((n) & 31)))
1.1 djm 116:
117: /*
118: * Prime testing defines
119: */
120:
1.7 djm 121: /* Minimum number of primality tests to perform */
1.12 djm 122: #define TRIAL_MINIMUM (4)
1.7 djm 123:
1.1 djm 124: /*
125: * Sieving data (XXX - move to struct)
126: */
127:
128: /* sieve 2**16 */
129: static u_int32_t *TinySieve, tinybits;
130:
131: /* sieve 2**30 in 2**16 parts */
132: static u_int32_t *SmallSieve, smallbits, smallbase;
133:
134: /* sieve relative to the initial value */
135: static u_int32_t *LargeSieve, largewords, largetries, largenumbers;
136: static u_int32_t largebits, largememory; /* megabytes */
137: static BIGNUM *largebase;
138:
1.11 avsm 139: int gen_candidates(FILE *, u_int32_t, u_int32_t, BIGNUM *);
1.26 dtucker 140: int prime_test(FILE *, FILE *, u_int32_t, u_int32_t, char *, unsigned long,
141: unsigned long);
1.1 djm 142:
143: /*
144: * print moduli out in consistent form,
145: */
146: static int
147: qfileout(FILE * ofile, u_int32_t otype, u_int32_t otests, u_int32_t otries,
148: u_int32_t osize, u_int32_t ogenerator, BIGNUM * omodulus)
149: {
150: struct tm *gtm;
151: time_t time_now;
152: int res;
153:
154: time(&time_now);
155: gtm = gmtime(&time_now);
1.36 dtucker 156: if (gtm == NULL)
157: return -1;
1.2 djm 158:
1.1 djm 159: res = fprintf(ofile, "%04d%02d%02d%02d%02d%02d %u %u %u %u %x ",
160: gtm->tm_year + 1900, gtm->tm_mon + 1, gtm->tm_mday,
161: gtm->tm_hour, gtm->tm_min, gtm->tm_sec,
162: otype, otests, otries, osize, ogenerator);
163:
164: if (res < 0)
165: return (-1);
166:
167: if (BN_print_fp(ofile, omodulus) < 1)
168: return (-1);
169:
170: res = fprintf(ofile, "\n");
171: fflush(ofile);
172:
173: return (res > 0 ? 0 : -1);
174: }
175:
176:
177: /*
178: ** Sieve p's and q's with small factors
179: */
180: static void
1.38 djm 181: sieve_large(u_int32_t s32)
1.1 djm 182: {
1.38 djm 183: u_int64_t r, u, s = s32;
1.1 djm 184:
1.38 djm 185: debug3("sieve_large %u", s32);
1.1 djm 186: largetries++;
187: /* r = largebase mod s */
1.38 djm 188: r = BN_mod_word(largebase, s32);
1.1 djm 189: if (r == 0)
190: u = 0; /* s divides into largebase exactly */
191: else
192: u = s - r; /* largebase+u is first entry divisible by s */
193:
1.38 djm 194: if (u < largebits * 2ULL) {
1.1 djm 195: /*
196: * The sieve omits p's and q's divisible by 2, so ensure that
197: * largebase+u is odd. Then, step through the sieve in
198: * increments of 2*s
199: */
200: if (u & 0x1)
201: u += s; /* Make largebase+u odd, and u even */
202:
203: /* Mark all multiples of 2*s */
204: for (u /= 2; u < largebits; u += s)
205: BIT_SET(LargeSieve, u);
206: }
207:
208: /* r = p mod s */
209: r = (2 * r + 1) % s;
210: if (r == 0)
211: u = 0; /* s divides p exactly */
212: else
213: u = s - r; /* p+u is first entry divisible by s */
214:
1.38 djm 215: if (u < largebits * 4ULL) {
1.1 djm 216: /*
217: * The sieve omits p's divisible by 4, so ensure that
218: * largebase+u is not. Then, step through the sieve in
219: * increments of 4*s
220: */
221: while (u & 0x3) {
222: if (SMALL_MAXIMUM - u < s)
223: return;
224: u += s;
225: }
226:
227: /* Mark all multiples of 4*s */
228: for (u /= 4; u < largebits; u += s)
229: BIT_SET(LargeSieve, u);
230: }
231: }
232:
233: /*
1.6 djm 234: * list candidates for Sophie-Germain primes (where q = (p-1)/2)
1.1 djm 235: * to standard output.
236: * The list is checked against small known primes (less than 2**30).
237: */
238: int
1.11 avsm 239: gen_candidates(FILE *out, u_int32_t memory, u_int32_t power, BIGNUM *start)
1.1 djm 240: {
241: BIGNUM *q;
242: u_int32_t j, r, s, t;
243: u_int32_t smallwords = TINY_NUMBER >> 6;
244: u_int32_t tinywords = TINY_NUMBER >> 6;
245: time_t time_start, time_stop;
1.11 avsm 246: u_int32_t i;
247: int ret = 0;
1.1 djm 248:
249: largememory = memory;
250:
1.7 djm 251: if (memory != 0 &&
1.12 djm 252: (memory < LARGE_MINIMUM || memory > LARGE_MAXIMUM)) {
1.7 djm 253: error("Invalid memory amount (min %ld, max %ld)",
254: LARGE_MINIMUM, LARGE_MAXIMUM);
255: return (-1);
256: }
257:
1.1 djm 258: /*
1.2 djm 259: * Set power to the length in bits of the prime to be generated.
260: * This is changed to 1 less than the desired safe prime moduli p.
261: */
1.1 djm 262: if (power > TEST_MAXIMUM) {
263: error("Too many bits: %u > %lu", power, TEST_MAXIMUM);
264: return (-1);
265: } else if (power < TEST_MINIMUM) {
266: error("Too few bits: %u < %u", power, TEST_MINIMUM);
267: return (-1);
268: }
269: power--; /* decrement before squaring */
270:
271: /*
1.2 djm 272: * The density of ordinary primes is on the order of 1/bits, so the
273: * density of safe primes should be about (1/bits)**2. Set test range
274: * to something well above bits**2 to be reasonably sure (but not
275: * guaranteed) of catching at least one safe prime.
1.1 djm 276: */
277: largewords = ((power * power) >> (SHIFT_WORD - TEST_POWER));
278:
279: /*
1.2 djm 280: * Need idea of how much memory is available. We don't have to use all
281: * of it.
1.1 djm 282: */
283: if (largememory > LARGE_MAXIMUM) {
284: logit("Limited memory: %u MB; limit %lu MB",
285: largememory, LARGE_MAXIMUM);
286: largememory = LARGE_MAXIMUM;
287: }
288:
289: if (largewords <= (largememory << SHIFT_MEGAWORD)) {
290: logit("Increased memory: %u MB; need %u bytes",
291: largememory, (largewords << SHIFT_BYTE));
292: largewords = (largememory << SHIFT_MEGAWORD);
293: } else if (largememory > 0) {
294: logit("Decreased memory: %u MB; want %u bytes",
295: largememory, (largewords << SHIFT_BYTE));
296: largewords = (largememory << SHIFT_MEGAWORD);
297: }
298:
1.13 djm 299: TinySieve = xcalloc(tinywords, sizeof(u_int32_t));
1.1 djm 300: tinybits = tinywords << SHIFT_WORD;
301:
1.13 djm 302: SmallSieve = xcalloc(smallwords, sizeof(u_int32_t));
1.1 djm 303: smallbits = smallwords << SHIFT_WORD;
304:
305: /*
306: * dynamically determine available memory
307: */
308: while ((LargeSieve = calloc(largewords, sizeof(u_int32_t))) == NULL)
309: largewords -= (1L << (SHIFT_MEGAWORD - 2)); /* 1/4 MB chunks */
310:
311: largebits = largewords << SHIFT_WORD;
312: largenumbers = largebits * 2; /* even numbers excluded */
313:
314: /* validation check: count the number of primes tried */
315: largetries = 0;
1.19 markus 316: if ((q = BN_new()) == NULL)
317: fatal("BN_new failed");
1.1 djm 318:
319: /*
1.2 djm 320: * Generate random starting point for subprime search, or use
321: * specified parameter.
1.1 djm 322: */
1.19 markus 323: if ((largebase = BN_new()) == NULL)
324: fatal("BN_new failed");
325: if (start == NULL) {
326: if (BN_rand(largebase, power, 1, 1) == 0)
327: fatal("BN_rand failed");
328: } else {
329: if (BN_copy(largebase, start) == NULL)
330: fatal("BN_copy: failed");
331: }
1.1 djm 332:
333: /* ensure odd */
1.19 markus 334: if (BN_set_bit(largebase, 0) == 0)
335: fatal("BN_set_bit: failed");
1.1 djm 336:
337: time(&time_start);
338:
1.2 djm 339: logit("%.24s Sieve next %u plus %u-bit", ctime(&time_start),
1.1 djm 340: largenumbers, power);
341: debug2("start point: 0x%s", BN_bn2hex(largebase));
342:
343: /*
1.2 djm 344: * TinySieve
345: */
1.1 djm 346: for (i = 0; i < tinybits; i++) {
347: if (BIT_TEST(TinySieve, i))
348: continue; /* 2*i+3 is composite */
349:
350: /* The next tiny prime */
351: t = 2 * i + 3;
352:
353: /* Mark all multiples of t */
354: for (j = i + t; j < tinybits; j += t)
355: BIT_SET(TinySieve, j);
356:
357: sieve_large(t);
358: }
359:
360: /*
1.2 djm 361: * Start the small block search at the next possible prime. To avoid
362: * fencepost errors, the last pass is skipped.
363: */
1.1 djm 364: for (smallbase = TINY_NUMBER + 3;
1.12 djm 365: smallbase < (SMALL_MAXIMUM - TINY_NUMBER);
366: smallbase += TINY_NUMBER) {
1.1 djm 367: for (i = 0; i < tinybits; i++) {
368: if (BIT_TEST(TinySieve, i))
369: continue; /* 2*i+3 is composite */
370:
371: /* The next tiny prime */
372: t = 2 * i + 3;
373: r = smallbase % t;
374:
375: if (r == 0) {
376: s = 0; /* t divides into smallbase exactly */
377: } else {
378: /* smallbase+s is first entry divisible by t */
379: s = t - r;
380: }
381:
382: /*
383: * The sieve omits even numbers, so ensure that
384: * smallbase+s is odd. Then, step through the sieve
385: * in increments of 2*t
386: */
387: if (s & 1)
388: s += t; /* Make smallbase+s odd, and s even */
389:
390: /* Mark all multiples of 2*t */
391: for (s /= 2; s < smallbits; s += t)
392: BIT_SET(SmallSieve, s);
393: }
394:
395: /*
1.2 djm 396: * SmallSieve
397: */
1.1 djm 398: for (i = 0; i < smallbits; i++) {
399: if (BIT_TEST(SmallSieve, i))
400: continue; /* 2*i+smallbase is composite */
401:
402: /* The next small prime */
403: sieve_large((2 * i) + smallbase);
404: }
405:
406: memset(SmallSieve, 0, smallwords << SHIFT_BYTE);
407: }
408:
409: time(&time_stop);
410:
1.32 deraadt 411: logit("%.24s Sieved with %u small primes in %lld seconds",
412: ctime(&time_stop), largetries, (long long)(time_stop - time_start));
1.1 djm 413:
414: for (j = r = 0; j < largebits; j++) {
415: if (BIT_TEST(LargeSieve, j))
416: continue; /* Definitely composite, skip */
417:
418: debug2("test q = largebase+%u", 2 * j);
1.19 markus 419: if (BN_set_word(q, 2 * j) == 0)
420: fatal("BN_set_word failed");
421: if (BN_add(q, q, largebase) == 0)
422: fatal("BN_add failed");
1.21 djm 423: if (qfileout(out, MODULI_TYPE_SOPHIE_GERMAIN,
424: MODULI_TESTS_SIEVE, largetries,
425: (power - 1) /* MSB */, (0), q) == -1) {
1.1 djm 426: ret = -1;
427: break;
428: }
429:
430: r++; /* count q */
431: }
432:
433: time(&time_stop);
434:
1.27 djm 435: free(LargeSieve);
436: free(SmallSieve);
437: free(TinySieve);
1.1 djm 438:
439: logit("%.24s Found %u candidates", ctime(&time_stop), r);
440:
441: return (ret);
442: }
443:
1.23 dtucker 444: static void
445: write_checkpoint(char *cpfile, u_int32_t lineno)
446: {
447: FILE *fp;
1.30 deraadt 448: char tmp[PATH_MAX];
1.39 ! dtucker 449: int r, writeok, closeok;
1.23 dtucker 450:
1.25 djm 451: r = snprintf(tmp, sizeof(tmp), "%s.XXXXXXXXXX", cpfile);
1.35 deraadt 452: if (r < 0 || r >= PATH_MAX) {
1.23 dtucker 453: logit("write_checkpoint: temp pathname too long");
454: return;
455: }
1.25 djm 456: if ((r = mkstemp(tmp)) == -1) {
457: logit("mkstemp(%s): %s", tmp, strerror(errno));
1.23 dtucker 458: return;
459: }
460: if ((fp = fdopen(r, "w")) == NULL) {
461: logit("write_checkpoint: fdopen: %s", strerror(errno));
1.29 doug 462: unlink(tmp);
1.23 dtucker 463: close(r);
464: return;
465: }
1.39 ! dtucker 466: writeok = (fprintf(fp, "%lu\n", (unsigned long)lineno) > 0);
! 467: closeok = (fclose(fp) == 0);
! 468: if (writeok && closeok && rename(tmp, cpfile) == 0) {
1.23 dtucker 469: debug3("wrote checkpoint line %lu to '%s'",
470: (unsigned long)lineno, cpfile);
1.39 ! dtucker 471: } else {
1.23 dtucker 472: logit("failed to write to checkpoint file '%s': %s", cpfile,
473: strerror(errno));
1.39 ! dtucker 474: (void)unlink(tmp);
! 475: }
1.23 dtucker 476: }
477:
478: static unsigned long
479: read_checkpoint(char *cpfile)
480: {
481: FILE *fp;
482: unsigned long lineno = 0;
483:
484: if ((fp = fopen(cpfile, "r")) == NULL)
485: return 0;
486: if (fscanf(fp, "%lu\n", &lineno) < 1)
487: logit("Failed to load checkpoint from '%s'", cpfile);
488: else
489: logit("Loaded checkpoint from '%s' line %lu", cpfile, lineno);
490: fclose(fp);
491: return lineno;
492: }
493:
1.28 dtucker 494: static unsigned long
495: count_lines(FILE *f)
496: {
497: unsigned long count = 0;
498: char lp[QLINESIZE + 1];
499:
500: if (fseek(f, 0, SEEK_SET) != 0) {
501: debug("input file is not seekable");
502: return ULONG_MAX;
503: }
504: while (fgets(lp, QLINESIZE + 1, f) != NULL)
505: count++;
506: rewind(f);
507: debug("input file has %lu lines", count);
508: return count;
509: }
510:
511: static char *
512: fmt_time(time_t seconds)
513: {
514: int day, hr, min;
515: static char buf[128];
516:
517: min = (seconds / 60) % 60;
518: hr = (seconds / 60 / 60) % 24;
519: day = seconds / 60 / 60 / 24;
520: if (day > 0)
521: snprintf(buf, sizeof buf, "%dd %d:%02d", day, hr, min);
522: else
523: snprintf(buf, sizeof buf, "%d:%02d", hr, min);
524: return buf;
525: }
526:
527: static void
528: print_progress(unsigned long start_lineno, unsigned long current_lineno,
529: unsigned long end_lineno)
530: {
531: static time_t time_start, time_prev;
532: time_t time_now, elapsed;
533: unsigned long num_to_process, processed, remaining, percent, eta;
534: double time_per_line;
535: char *eta_str;
536:
537: time_now = monotime();
538: if (time_start == 0) {
539: time_start = time_prev = time_now;
540: return;
541: }
542: /* print progress after 1m then once per 5m */
543: if (time_now - time_prev < 5 * 60)
544: return;
545: time_prev = time_now;
546: elapsed = time_now - time_start;
547: processed = current_lineno - start_lineno;
548: remaining = end_lineno - current_lineno;
549: num_to_process = end_lineno - start_lineno;
550: time_per_line = (double)elapsed / processed;
551: /* if we don't know how many we're processing just report count+time */
552: time(&time_now);
553: if (end_lineno == ULONG_MAX) {
554: logit("%.24s processed %lu in %s", ctime(&time_now),
555: processed, fmt_time(elapsed));
556: return;
557: }
558: percent = 100 * processed / num_to_process;
559: eta = time_per_line * remaining;
560: eta_str = xstrdup(fmt_time(eta));
561: logit("%.24s processed %lu of %lu (%lu%%) in %s, ETA %s",
562: ctime(&time_now), processed, num_to_process, percent,
563: fmt_time(elapsed), eta_str);
564: free(eta_str);
565: }
566:
1.1 djm 567: /*
568: * perform a Miller-Rabin primality test
569: * on the list of candidates
570: * (checking both q and p)
571: * The result is a list of so-call "safe" primes
572: */
573: int
1.23 dtucker 574: prime_test(FILE *in, FILE *out, u_int32_t trials, u_int32_t generator_wanted,
1.26 dtucker 575: char *checkpoint_file, unsigned long start_lineno, unsigned long num_lines)
1.1 djm 576: {
577: BIGNUM *q, *p, *a;
578: char *cp, *lp;
579: u_int32_t count_in = 0, count_out = 0, count_possible = 0;
580: u_int32_t generator_known, in_tests, in_tries, in_type, in_size;
1.26 dtucker 581: unsigned long last_processed = 0, end_lineno;
1.1 djm 582: time_t time_start, time_stop;
1.33 tb 583: int res, is_prime;
1.7 djm 584:
585: if (trials < TRIAL_MINIMUM) {
586: error("Minimum primality trials is %d", TRIAL_MINIMUM);
587: return (-1);
588: }
1.1 djm 589:
1.28 dtucker 590: if (num_lines == 0)
591: end_lineno = count_lines(in);
592: else
593: end_lineno = start_lineno + num_lines;
594:
1.1 djm 595: time(&time_start);
596:
1.19 markus 597: if ((p = BN_new()) == NULL)
598: fatal("BN_new failed");
599: if ((q = BN_new()) == NULL)
600: fatal("BN_new failed");
1.1 djm 601:
602: debug2("%.24s Final %u Miller-Rabin trials (%x generator)",
603: ctime(&time_start), trials, generator_wanted);
604:
1.23 dtucker 605: if (checkpoint_file != NULL)
606: last_processed = read_checkpoint(checkpoint_file);
1.31 deraadt 607: last_processed = start_lineno = MAXIMUM(last_processed, start_lineno);
1.28 dtucker 608: if (end_lineno == ULONG_MAX)
609: debug("process from line %lu from pipe", last_processed);
1.26 dtucker 610: else
1.28 dtucker 611: debug("process from line %lu to line %lu", last_processed,
612: end_lineno);
1.23 dtucker 613:
1.1 djm 614: res = 0;
615: lp = xmalloc(QLINESIZE + 1);
1.26 dtucker 616: while (fgets(lp, QLINESIZE + 1, in) != NULL && count_in < end_lineno) {
1.1 djm 617: count_in++;
1.28 dtucker 618: if (count_in <= last_processed) {
619: debug3("skipping line %u, before checkpoint or "
620: "specified start line", count_in);
621: continue;
622: }
623: if (checkpoint_file != NULL)
1.23 dtucker 624: write_checkpoint(checkpoint_file, count_in);
1.28 dtucker 625: print_progress(start_lineno, count_in, end_lineno);
1.20 ray 626: if (strlen(lp) < 14 || *lp == '!' || *lp == '#') {
1.1 djm 627: debug2("%10u: comment or short line", count_in);
628: continue;
629: }
630:
631: /* XXX - fragile parser */
632: /* time */
633: cp = &lp[14]; /* (skip) */
634:
635: /* type */
636: in_type = strtoul(cp, &cp, 10);
637:
638: /* tests */
639: in_tests = strtoul(cp, &cp, 10);
640:
1.21 djm 641: if (in_tests & MODULI_TESTS_COMPOSITE) {
1.1 djm 642: debug2("%10u: known composite", count_in);
643: continue;
644: }
1.5 djm 645:
1.1 djm 646: /* tries */
647: in_tries = strtoul(cp, &cp, 10);
648:
649: /* size (most significant bit) */
650: in_size = strtoul(cp, &cp, 10);
651:
652: /* generator (hex) */
653: generator_known = strtoul(cp, &cp, 16);
654:
655: /* Skip white space */
656: cp += strspn(cp, " ");
657:
658: /* modulus (hex) */
659: switch (in_type) {
1.21 djm 660: case MODULI_TYPE_SOPHIE_GERMAIN:
1.6 djm 661: debug2("%10u: (%u) Sophie-Germain", count_in, in_type);
1.1 djm 662: a = q;
1.19 markus 663: if (BN_hex2bn(&a, cp) == 0)
664: fatal("BN_hex2bn failed");
1.1 djm 665: /* p = 2*q + 1 */
1.19 markus 666: if (BN_lshift(p, q, 1) == 0)
667: fatal("BN_lshift failed");
668: if (BN_add_word(p, 1) == 0)
669: fatal("BN_add_word failed");
1.1 djm 670: in_size += 1;
671: generator_known = 0;
672: break;
1.21 djm 673: case MODULI_TYPE_UNSTRUCTURED:
674: case MODULI_TYPE_SAFE:
675: case MODULI_TYPE_SCHNORR:
676: case MODULI_TYPE_STRONG:
677: case MODULI_TYPE_UNKNOWN:
1.1 djm 678: debug2("%10u: (%u)", count_in, in_type);
679: a = p;
1.19 markus 680: if (BN_hex2bn(&a, cp) == 0)
681: fatal("BN_hex2bn failed");
1.1 djm 682: /* q = (p-1) / 2 */
1.19 markus 683: if (BN_rshift(q, p, 1) == 0)
684: fatal("BN_rshift failed");
1.1 djm 685: break;
1.5 djm 686: default:
687: debug2("Unknown prime type");
688: break;
1.1 djm 689: }
690:
691: /*
692: * due to earlier inconsistencies in interpretation, check
693: * the proposed bit size.
694: */
1.11 avsm 695: if ((u_int32_t)BN_num_bits(p) != (in_size + 1)) {
1.1 djm 696: debug2("%10u: bit size %u mismatch", count_in, in_size);
697: continue;
698: }
699: if (in_size < QSIZE_MINIMUM) {
700: debug2("%10u: bit size %u too short", count_in, in_size);
701: continue;
702: }
703:
1.21 djm 704: if (in_tests & MODULI_TESTS_MILLER_RABIN)
1.1 djm 705: in_tries += trials;
706: else
707: in_tries = trials;
1.5 djm 708:
1.1 djm 709: /*
710: * guess unknown generator
711: */
712: if (generator_known == 0) {
713: if (BN_mod_word(p, 24) == 11)
714: generator_known = 2;
715: else {
716: u_int32_t r = BN_mod_word(p, 10);
717:
1.5 djm 718: if (r == 3 || r == 7)
1.1 djm 719: generator_known = 5;
720: }
721: }
722: /*
723: * skip tests when desired generator doesn't match
724: */
725: if (generator_wanted > 0 &&
726: generator_wanted != generator_known) {
727: debug2("%10u: generator %d != %d",
728: count_in, generator_known, generator_wanted);
1.4 dtucker 729: continue;
730: }
731:
732: /*
733: * Primes with no known generator are useless for DH, so
734: * skip those.
735: */
736: if (generator_known == 0) {
737: debug2("%10u: no known generator", count_in);
1.1 djm 738: continue;
739: }
740:
741: count_possible++;
742:
743: /*
1.2 djm 744: * The (1/4)^N performance bound on Miller-Rabin is
745: * extremely pessimistic, so don't spend a lot of time
746: * really verifying that q is prime until after we know
747: * that p is also prime. A single pass will weed out the
1.1 djm 748: * vast majority of composite q's.
749: */
1.37 djm 750: is_prime = BN_is_prime_ex(q, 1, NULL, NULL);
1.33 tb 751: if (is_prime < 0)
752: fatal("BN_is_prime_ex failed");
753: if (is_prime == 0) {
1.5 djm 754: debug("%10u: q failed first possible prime test",
1.1 djm 755: count_in);
756: continue;
757: }
1.2 djm 758:
1.1 djm 759: /*
1.2 djm 760: * q is possibly prime, so go ahead and really make sure
761: * that p is prime. If it is, then we can go back and do
762: * the same for q. If p is composite, chances are that
1.1 djm 763: * will show up on the first Rabin-Miller iteration so it
764: * doesn't hurt to specify a high iteration count.
765: */
1.37 djm 766: is_prime = BN_is_prime_ex(p, trials, NULL, NULL);
1.33 tb 767: if (is_prime < 0)
768: fatal("BN_is_prime_ex failed");
769: if (is_prime == 0) {
1.5 djm 770: debug("%10u: p is not prime", count_in);
1.1 djm 771: continue;
772: }
773: debug("%10u: p is almost certainly prime", count_in);
774:
775: /* recheck q more rigorously */
1.37 djm 776: is_prime = BN_is_prime_ex(q, trials - 1, NULL, NULL);
1.33 tb 777: if (is_prime < 0)
778: fatal("BN_is_prime_ex failed");
779: if (is_prime == 0) {
1.1 djm 780: debug("%10u: q is not prime", count_in);
781: continue;
782: }
783: debug("%10u: q is almost certainly prime", count_in);
784:
1.21 djm 785: if (qfileout(out, MODULI_TYPE_SAFE,
786: in_tests | MODULI_TESTS_MILLER_RABIN,
1.1 djm 787: in_tries, in_size, generator_known, p)) {
788: res = -1;
789: break;
790: }
791:
792: count_out++;
793: }
794:
795: time(&time_stop);
1.27 djm 796: free(lp);
1.1 djm 797: BN_free(p);
798: BN_free(q);
1.23 dtucker 799:
800: if (checkpoint_file != NULL)
801: unlink(checkpoint_file);
1.1 djm 802:
803: logit("%.24s Found %u safe primes of %u candidates in %ld seconds",
1.2 djm 804: ctime(&time_stop), count_out, count_possible,
1.1 djm 805: (long) (time_stop - time_start));
806:
807: return (res);
808: }
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