Annotation of src/usr.bin/ssh/moduli.c, Revision 1.29
1.29 ! doug 1: /* $OpenBSD: moduli.c,v 1.28 2013/10/24 00:49:49 dtucker 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:
1.24 stsp 40: #include <sys/param.h>
1.14 stevesk 41: #include <sys/types.h>
42:
43: #include <openssl/bn.h>
1.21 djm 44: #include <openssl/dh.h>
1.14 stevesk 45:
1.24 stsp 46: #include <errno.h>
1.17 stevesk 47: #include <stdio.h>
1.16 stevesk 48: #include <stdlib.h>
1.15 stevesk 49: #include <string.h>
1.18 deraadt 50: #include <stdarg.h>
1.14 stevesk 51: #include <time.h>
1.23 dtucker 52: #include <unistd.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);
1.2 djm 156:
1.1 djm 157: res = fprintf(ofile, "%04d%02d%02d%02d%02d%02d %u %u %u %u %x ",
158: gtm->tm_year + 1900, gtm->tm_mon + 1, gtm->tm_mday,
159: gtm->tm_hour, gtm->tm_min, gtm->tm_sec,
160: otype, otests, otries, osize, ogenerator);
161:
162: if (res < 0)
163: return (-1);
164:
165: if (BN_print_fp(ofile, omodulus) < 1)
166: return (-1);
167:
168: res = fprintf(ofile, "\n");
169: fflush(ofile);
170:
171: return (res > 0 ? 0 : -1);
172: }
173:
174:
175: /*
176: ** Sieve p's and q's with small factors
177: */
178: static void
179: sieve_large(u_int32_t s)
180: {
181: u_int32_t r, u;
182:
1.5 djm 183: debug3("sieve_large %u", s);
1.1 djm 184: largetries++;
185: /* r = largebase mod s */
186: r = BN_mod_word(largebase, s);
187: if (r == 0)
188: u = 0; /* s divides into largebase exactly */
189: else
190: u = s - r; /* largebase+u is first entry divisible by s */
191:
192: if (u < largebits * 2) {
193: /*
194: * The sieve omits p's and q's divisible by 2, so ensure that
195: * largebase+u is odd. Then, step through the sieve in
196: * increments of 2*s
197: */
198: if (u & 0x1)
199: u += s; /* Make largebase+u odd, and u even */
200:
201: /* Mark all multiples of 2*s */
202: for (u /= 2; u < largebits; u += s)
203: BIT_SET(LargeSieve, u);
204: }
205:
206: /* r = p mod s */
207: r = (2 * r + 1) % s;
208: if (r == 0)
209: u = 0; /* s divides p exactly */
210: else
211: u = s - r; /* p+u is first entry divisible by s */
212:
213: if (u < largebits * 4) {
214: /*
215: * The sieve omits p's divisible by 4, so ensure that
216: * largebase+u is not. Then, step through the sieve in
217: * increments of 4*s
218: */
219: while (u & 0x3) {
220: if (SMALL_MAXIMUM - u < s)
221: return;
222: u += s;
223: }
224:
225: /* Mark all multiples of 4*s */
226: for (u /= 4; u < largebits; u += s)
227: BIT_SET(LargeSieve, u);
228: }
229: }
230:
231: /*
1.6 djm 232: * list candidates for Sophie-Germain primes (where q = (p-1)/2)
1.1 djm 233: * to standard output.
234: * The list is checked against small known primes (less than 2**30).
235: */
236: int
1.11 avsm 237: gen_candidates(FILE *out, u_int32_t memory, u_int32_t power, BIGNUM *start)
1.1 djm 238: {
239: BIGNUM *q;
240: u_int32_t j, r, s, t;
241: u_int32_t smallwords = TINY_NUMBER >> 6;
242: u_int32_t tinywords = TINY_NUMBER >> 6;
243: time_t time_start, time_stop;
1.11 avsm 244: u_int32_t i;
245: int ret = 0;
1.1 djm 246:
247: largememory = memory;
248:
1.7 djm 249: if (memory != 0 &&
1.12 djm 250: (memory < LARGE_MINIMUM || memory > LARGE_MAXIMUM)) {
1.7 djm 251: error("Invalid memory amount (min %ld, max %ld)",
252: LARGE_MINIMUM, LARGE_MAXIMUM);
253: return (-1);
254: }
255:
1.1 djm 256: /*
1.2 djm 257: * Set power to the length in bits of the prime to be generated.
258: * This is changed to 1 less than the desired safe prime moduli p.
259: */
1.1 djm 260: if (power > TEST_MAXIMUM) {
261: error("Too many bits: %u > %lu", power, TEST_MAXIMUM);
262: return (-1);
263: } else if (power < TEST_MINIMUM) {
264: error("Too few bits: %u < %u", power, TEST_MINIMUM);
265: return (-1);
266: }
267: power--; /* decrement before squaring */
268:
269: /*
1.2 djm 270: * The density of ordinary primes is on the order of 1/bits, so the
271: * density of safe primes should be about (1/bits)**2. Set test range
272: * to something well above bits**2 to be reasonably sure (but not
273: * guaranteed) of catching at least one safe prime.
1.1 djm 274: */
275: largewords = ((power * power) >> (SHIFT_WORD - TEST_POWER));
276:
277: /*
1.2 djm 278: * Need idea of how much memory is available. We don't have to use all
279: * of it.
1.1 djm 280: */
281: if (largememory > LARGE_MAXIMUM) {
282: logit("Limited memory: %u MB; limit %lu MB",
283: largememory, LARGE_MAXIMUM);
284: largememory = LARGE_MAXIMUM;
285: }
286:
287: if (largewords <= (largememory << SHIFT_MEGAWORD)) {
288: logit("Increased memory: %u MB; need %u bytes",
289: largememory, (largewords << SHIFT_BYTE));
290: largewords = (largememory << SHIFT_MEGAWORD);
291: } else if (largememory > 0) {
292: logit("Decreased memory: %u MB; want %u bytes",
293: largememory, (largewords << SHIFT_BYTE));
294: largewords = (largememory << SHIFT_MEGAWORD);
295: }
296:
1.13 djm 297: TinySieve = xcalloc(tinywords, sizeof(u_int32_t));
1.1 djm 298: tinybits = tinywords << SHIFT_WORD;
299:
1.13 djm 300: SmallSieve = xcalloc(smallwords, sizeof(u_int32_t));
1.1 djm 301: smallbits = smallwords << SHIFT_WORD;
302:
303: /*
304: * dynamically determine available memory
305: */
306: while ((LargeSieve = calloc(largewords, sizeof(u_int32_t))) == NULL)
307: largewords -= (1L << (SHIFT_MEGAWORD - 2)); /* 1/4 MB chunks */
308:
309: largebits = largewords << SHIFT_WORD;
310: largenumbers = largebits * 2; /* even numbers excluded */
311:
312: /* validation check: count the number of primes tried */
313: largetries = 0;
1.19 markus 314: if ((q = BN_new()) == NULL)
315: fatal("BN_new failed");
1.1 djm 316:
317: /*
1.2 djm 318: * Generate random starting point for subprime search, or use
319: * specified parameter.
1.1 djm 320: */
1.19 markus 321: if ((largebase = BN_new()) == NULL)
322: fatal("BN_new failed");
323: if (start == NULL) {
324: if (BN_rand(largebase, power, 1, 1) == 0)
325: fatal("BN_rand failed");
326: } else {
327: if (BN_copy(largebase, start) == NULL)
328: fatal("BN_copy: failed");
329: }
1.1 djm 330:
331: /* ensure odd */
1.19 markus 332: if (BN_set_bit(largebase, 0) == 0)
333: fatal("BN_set_bit: failed");
1.1 djm 334:
335: time(&time_start);
336:
1.2 djm 337: logit("%.24s Sieve next %u plus %u-bit", ctime(&time_start),
1.1 djm 338: largenumbers, power);
339: debug2("start point: 0x%s", BN_bn2hex(largebase));
340:
341: /*
1.2 djm 342: * TinySieve
343: */
1.1 djm 344: for (i = 0; i < tinybits; i++) {
345: if (BIT_TEST(TinySieve, i))
346: continue; /* 2*i+3 is composite */
347:
348: /* The next tiny prime */
349: t = 2 * i + 3;
350:
351: /* Mark all multiples of t */
352: for (j = i + t; j < tinybits; j += t)
353: BIT_SET(TinySieve, j);
354:
355: sieve_large(t);
356: }
357:
358: /*
1.2 djm 359: * Start the small block search at the next possible prime. To avoid
360: * fencepost errors, the last pass is skipped.
361: */
1.1 djm 362: for (smallbase = TINY_NUMBER + 3;
1.12 djm 363: smallbase < (SMALL_MAXIMUM - TINY_NUMBER);
364: smallbase += TINY_NUMBER) {
1.1 djm 365: for (i = 0; i < tinybits; i++) {
366: if (BIT_TEST(TinySieve, i))
367: continue; /* 2*i+3 is composite */
368:
369: /* The next tiny prime */
370: t = 2 * i + 3;
371: r = smallbase % t;
372:
373: if (r == 0) {
374: s = 0; /* t divides into smallbase exactly */
375: } else {
376: /* smallbase+s is first entry divisible by t */
377: s = t - r;
378: }
379:
380: /*
381: * The sieve omits even numbers, so ensure that
382: * smallbase+s is odd. Then, step through the sieve
383: * in increments of 2*t
384: */
385: if (s & 1)
386: s += t; /* Make smallbase+s odd, and s even */
387:
388: /* Mark all multiples of 2*t */
389: for (s /= 2; s < smallbits; s += t)
390: BIT_SET(SmallSieve, s);
391: }
392:
393: /*
1.2 djm 394: * SmallSieve
395: */
1.1 djm 396: for (i = 0; i < smallbits; i++) {
397: if (BIT_TEST(SmallSieve, i))
398: continue; /* 2*i+smallbase is composite */
399:
400: /* The next small prime */
401: sieve_large((2 * i) + smallbase);
402: }
403:
404: memset(SmallSieve, 0, smallwords << SHIFT_BYTE);
405: }
406:
407: time(&time_stop);
408:
409: logit("%.24s Sieved with %u small primes in %ld seconds",
410: ctime(&time_stop), largetries, (long) (time_stop - time_start));
411:
412: for (j = r = 0; j < largebits; j++) {
413: if (BIT_TEST(LargeSieve, j))
414: continue; /* Definitely composite, skip */
415:
416: debug2("test q = largebase+%u", 2 * j);
1.19 markus 417: if (BN_set_word(q, 2 * j) == 0)
418: fatal("BN_set_word failed");
419: if (BN_add(q, q, largebase) == 0)
420: fatal("BN_add failed");
1.21 djm 421: if (qfileout(out, MODULI_TYPE_SOPHIE_GERMAIN,
422: MODULI_TESTS_SIEVE, largetries,
423: (power - 1) /* MSB */, (0), q) == -1) {
1.1 djm 424: ret = -1;
425: break;
426: }
427:
428: r++; /* count q */
429: }
430:
431: time(&time_stop);
432:
1.27 djm 433: free(LargeSieve);
434: free(SmallSieve);
435: free(TinySieve);
1.1 djm 436:
437: logit("%.24s Found %u candidates", ctime(&time_stop), r);
438:
439: return (ret);
440: }
441:
1.23 dtucker 442: static void
443: write_checkpoint(char *cpfile, u_int32_t lineno)
444: {
445: FILE *fp;
1.25 djm 446: char tmp[MAXPATHLEN];
1.23 dtucker 447: int r;
448:
1.25 djm 449: r = snprintf(tmp, sizeof(tmp), "%s.XXXXXXXXXX", cpfile);
1.23 dtucker 450: if (r == -1 || r >= MAXPATHLEN) {
451: logit("write_checkpoint: temp pathname too long");
452: return;
453: }
1.25 djm 454: if ((r = mkstemp(tmp)) == -1) {
455: logit("mkstemp(%s): %s", tmp, strerror(errno));
1.23 dtucker 456: return;
457: }
458: if ((fp = fdopen(r, "w")) == NULL) {
459: logit("write_checkpoint: fdopen: %s", strerror(errno));
1.29 ! doug 460: unlink(tmp);
1.23 dtucker 461: close(r);
462: return;
463: }
464: if (fprintf(fp, "%lu\n", (unsigned long)lineno) > 0 && fclose(fp) == 0
1.25 djm 465: && rename(tmp, cpfile) == 0)
1.23 dtucker 466: debug3("wrote checkpoint line %lu to '%s'",
467: (unsigned long)lineno, cpfile);
468: else
469: logit("failed to write to checkpoint file '%s': %s", cpfile,
470: strerror(errno));
471: }
472:
473: static unsigned long
474: read_checkpoint(char *cpfile)
475: {
476: FILE *fp;
477: unsigned long lineno = 0;
478:
479: if ((fp = fopen(cpfile, "r")) == NULL)
480: return 0;
481: if (fscanf(fp, "%lu\n", &lineno) < 1)
482: logit("Failed to load checkpoint from '%s'", cpfile);
483: else
484: logit("Loaded checkpoint from '%s' line %lu", cpfile, lineno);
485: fclose(fp);
486: return lineno;
487: }
488:
1.28 dtucker 489: static unsigned long
490: count_lines(FILE *f)
491: {
492: unsigned long count = 0;
493: char lp[QLINESIZE + 1];
494:
495: if (fseek(f, 0, SEEK_SET) != 0) {
496: debug("input file is not seekable");
497: return ULONG_MAX;
498: }
499: while (fgets(lp, QLINESIZE + 1, f) != NULL)
500: count++;
501: rewind(f);
502: debug("input file has %lu lines", count);
503: return count;
504: }
505:
506: static char *
507: fmt_time(time_t seconds)
508: {
509: int day, hr, min;
510: static char buf[128];
511:
512: min = (seconds / 60) % 60;
513: hr = (seconds / 60 / 60) % 24;
514: day = seconds / 60 / 60 / 24;
515: if (day > 0)
516: snprintf(buf, sizeof buf, "%dd %d:%02d", day, hr, min);
517: else
518: snprintf(buf, sizeof buf, "%d:%02d", hr, min);
519: return buf;
520: }
521:
522: static void
523: print_progress(unsigned long start_lineno, unsigned long current_lineno,
524: unsigned long end_lineno)
525: {
526: static time_t time_start, time_prev;
527: time_t time_now, elapsed;
528: unsigned long num_to_process, processed, remaining, percent, eta;
529: double time_per_line;
530: char *eta_str;
531:
532: time_now = monotime();
533: if (time_start == 0) {
534: time_start = time_prev = time_now;
535: return;
536: }
537: /* print progress after 1m then once per 5m */
538: if (time_now - time_prev < 5 * 60)
539: return;
540: time_prev = time_now;
541: elapsed = time_now - time_start;
542: processed = current_lineno - start_lineno;
543: remaining = end_lineno - current_lineno;
544: num_to_process = end_lineno - start_lineno;
545: time_per_line = (double)elapsed / processed;
546: /* if we don't know how many we're processing just report count+time */
547: time(&time_now);
548: if (end_lineno == ULONG_MAX) {
549: logit("%.24s processed %lu in %s", ctime(&time_now),
550: processed, fmt_time(elapsed));
551: return;
552: }
553: percent = 100 * processed / num_to_process;
554: eta = time_per_line * remaining;
555: eta_str = xstrdup(fmt_time(eta));
556: logit("%.24s processed %lu of %lu (%lu%%) in %s, ETA %s",
557: ctime(&time_now), processed, num_to_process, percent,
558: fmt_time(elapsed), eta_str);
559: free(eta_str);
560: }
561:
1.1 djm 562: /*
563: * perform a Miller-Rabin primality test
564: * on the list of candidates
565: * (checking both q and p)
566: * The result is a list of so-call "safe" primes
567: */
568: int
1.23 dtucker 569: prime_test(FILE *in, FILE *out, u_int32_t trials, u_int32_t generator_wanted,
1.26 dtucker 570: char *checkpoint_file, unsigned long start_lineno, unsigned long num_lines)
1.1 djm 571: {
572: BIGNUM *q, *p, *a;
573: BN_CTX *ctx;
574: char *cp, *lp;
575: u_int32_t count_in = 0, count_out = 0, count_possible = 0;
576: u_int32_t generator_known, in_tests, in_tries, in_type, in_size;
1.26 dtucker 577: unsigned long last_processed = 0, end_lineno;
1.1 djm 578: time_t time_start, time_stop;
579: int res;
1.7 djm 580:
581: if (trials < TRIAL_MINIMUM) {
582: error("Minimum primality trials is %d", TRIAL_MINIMUM);
583: return (-1);
584: }
1.1 djm 585:
1.28 dtucker 586: if (num_lines == 0)
587: end_lineno = count_lines(in);
588: else
589: end_lineno = start_lineno + num_lines;
590:
1.1 djm 591: time(&time_start);
592:
1.19 markus 593: if ((p = BN_new()) == NULL)
594: fatal("BN_new failed");
595: if ((q = BN_new()) == NULL)
596: fatal("BN_new failed");
597: if ((ctx = BN_CTX_new()) == NULL)
598: fatal("BN_CTX_new failed");
1.1 djm 599:
600: debug2("%.24s Final %u Miller-Rabin trials (%x generator)",
601: ctime(&time_start), trials, generator_wanted);
602:
1.23 dtucker 603: if (checkpoint_file != NULL)
604: last_processed = read_checkpoint(checkpoint_file);
1.28 dtucker 605: last_processed = start_lineno = MAX(last_processed, start_lineno);
606: if (end_lineno == ULONG_MAX)
607: debug("process from line %lu from pipe", last_processed);
1.26 dtucker 608: else
1.28 dtucker 609: debug("process from line %lu to line %lu", last_processed,
610: end_lineno);
1.23 dtucker 611:
1.1 djm 612: res = 0;
613: lp = xmalloc(QLINESIZE + 1);
1.26 dtucker 614: while (fgets(lp, QLINESIZE + 1, in) != NULL && count_in < end_lineno) {
1.1 djm 615: count_in++;
1.28 dtucker 616: if (count_in <= last_processed) {
617: debug3("skipping line %u, before checkpoint or "
618: "specified start line", count_in);
619: continue;
620: }
621: if (checkpoint_file != NULL)
1.23 dtucker 622: write_checkpoint(checkpoint_file, count_in);
1.28 dtucker 623: print_progress(start_lineno, count_in, end_lineno);
1.20 ray 624: if (strlen(lp) < 14 || *lp == '!' || *lp == '#') {
1.1 djm 625: debug2("%10u: comment or short line", count_in);
626: continue;
627: }
628:
629: /* XXX - fragile parser */
630: /* time */
631: cp = &lp[14]; /* (skip) */
632:
633: /* type */
634: in_type = strtoul(cp, &cp, 10);
635:
636: /* tests */
637: in_tests = strtoul(cp, &cp, 10);
638:
1.21 djm 639: if (in_tests & MODULI_TESTS_COMPOSITE) {
1.1 djm 640: debug2("%10u: known composite", count_in);
641: continue;
642: }
1.5 djm 643:
1.1 djm 644: /* tries */
645: in_tries = strtoul(cp, &cp, 10);
646:
647: /* size (most significant bit) */
648: in_size = strtoul(cp, &cp, 10);
649:
650: /* generator (hex) */
651: generator_known = strtoul(cp, &cp, 16);
652:
653: /* Skip white space */
654: cp += strspn(cp, " ");
655:
656: /* modulus (hex) */
657: switch (in_type) {
1.21 djm 658: case MODULI_TYPE_SOPHIE_GERMAIN:
1.6 djm 659: debug2("%10u: (%u) Sophie-Germain", count_in, in_type);
1.1 djm 660: a = q;
1.19 markus 661: if (BN_hex2bn(&a, cp) == 0)
662: fatal("BN_hex2bn failed");
1.1 djm 663: /* p = 2*q + 1 */
1.19 markus 664: if (BN_lshift(p, q, 1) == 0)
665: fatal("BN_lshift failed");
666: if (BN_add_word(p, 1) == 0)
667: fatal("BN_add_word failed");
1.1 djm 668: in_size += 1;
669: generator_known = 0;
670: break;
1.21 djm 671: case MODULI_TYPE_UNSTRUCTURED:
672: case MODULI_TYPE_SAFE:
673: case MODULI_TYPE_SCHNORR:
674: case MODULI_TYPE_STRONG:
675: case MODULI_TYPE_UNKNOWN:
1.1 djm 676: debug2("%10u: (%u)", count_in, in_type);
677: a = p;
1.19 markus 678: if (BN_hex2bn(&a, cp) == 0)
679: fatal("BN_hex2bn failed");
1.1 djm 680: /* q = (p-1) / 2 */
1.19 markus 681: if (BN_rshift(q, p, 1) == 0)
682: fatal("BN_rshift failed");
1.1 djm 683: break;
1.5 djm 684: default:
685: debug2("Unknown prime type");
686: break;
1.1 djm 687: }
688:
689: /*
690: * due to earlier inconsistencies in interpretation, check
691: * the proposed bit size.
692: */
1.11 avsm 693: if ((u_int32_t)BN_num_bits(p) != (in_size + 1)) {
1.1 djm 694: debug2("%10u: bit size %u mismatch", count_in, in_size);
695: continue;
696: }
697: if (in_size < QSIZE_MINIMUM) {
698: debug2("%10u: bit size %u too short", count_in, in_size);
699: continue;
700: }
701:
1.21 djm 702: if (in_tests & MODULI_TESTS_MILLER_RABIN)
1.1 djm 703: in_tries += trials;
704: else
705: in_tries = trials;
1.5 djm 706:
1.1 djm 707: /*
708: * guess unknown generator
709: */
710: if (generator_known == 0) {
711: if (BN_mod_word(p, 24) == 11)
712: generator_known = 2;
713: else if (BN_mod_word(p, 12) == 5)
714: generator_known = 3;
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: */
1.22 djm 750: if (BN_is_prime_ex(q, 1, ctx, NULL) <= 0) {
1.5 djm 751: debug("%10u: q failed first possible prime test",
1.1 djm 752: count_in);
753: continue;
754: }
1.2 djm 755:
1.1 djm 756: /*
1.2 djm 757: * q is possibly prime, so go ahead and really make sure
758: * that p is prime. If it is, then we can go back and do
759: * the same for q. If p is composite, chances are that
1.1 djm 760: * will show up on the first Rabin-Miller iteration so it
761: * doesn't hurt to specify a high iteration count.
762: */
1.22 djm 763: if (!BN_is_prime_ex(p, trials, ctx, NULL)) {
1.5 djm 764: debug("%10u: p is not prime", count_in);
1.1 djm 765: continue;
766: }
767: debug("%10u: p is almost certainly prime", count_in);
768:
769: /* recheck q more rigorously */
1.22 djm 770: if (!BN_is_prime_ex(q, trials - 1, ctx, NULL)) {
1.1 djm 771: debug("%10u: q is not prime", count_in);
772: continue;
773: }
774: debug("%10u: q is almost certainly prime", count_in);
775:
1.21 djm 776: if (qfileout(out, MODULI_TYPE_SAFE,
777: in_tests | MODULI_TESTS_MILLER_RABIN,
1.1 djm 778: in_tries, in_size, generator_known, p)) {
779: res = -1;
780: break;
781: }
782:
783: count_out++;
784: }
785:
786: time(&time_stop);
1.27 djm 787: free(lp);
1.1 djm 788: BN_free(p);
789: BN_free(q);
790: BN_CTX_free(ctx);
1.23 dtucker 791:
792: if (checkpoint_file != NULL)
793: unlink(checkpoint_file);
1.1 djm 794:
795: logit("%.24s Found %u safe primes of %u candidates in %ld seconds",
1.2 djm 796: ctime(&time_stop), count_out, count_possible,
1.1 djm 797: (long) (time_stop - time_start));
798:
799: return (res);
800: }
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