Annotation of src/usr.bin/ssh/moduli.c, Revision 1.30
1.30 ! deraadt 1: /* $OpenBSD: moduli.c,v 1.29 2014/08/21 01:08:52 doug 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:
1.30 ! deraadt 40: #include <sys/param.h> /* MAX */
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>
1.30 ! deraadt 53: #include <limits.h>
1.14 stevesk 54:
1.1 djm 55: #include "xmalloc.h"
1.21 djm 56: #include "dh.h"
1.1 djm 57: #include "log.h"
1.28 dtucker 58: #include "misc.h"
1.1 djm 59:
60: /*
61: * File output defines
62: */
63:
64: /* need line long enough for largest moduli plus headers */
1.9 deraadt 65: #define QLINESIZE (100+8192)
1.1 djm 66:
1.5 djm 67: /*
68: * Size: decimal.
1.1 djm 69: * Specifies the number of the most significant bit (0 to M).
1.5 djm 70: * WARNING: internally, usually 1 to N.
1.1 djm 71: */
1.9 deraadt 72: #define QSIZE_MINIMUM (511)
1.1 djm 73:
74: /*
75: * Prime sieving defines
76: */
77:
78: /* Constant: assuming 8 bit bytes and 32 bit words */
1.9 deraadt 79: #define SHIFT_BIT (3)
80: #define SHIFT_BYTE (2)
81: #define SHIFT_WORD (SHIFT_BIT+SHIFT_BYTE)
82: #define SHIFT_MEGABYTE (20)
83: #define SHIFT_MEGAWORD (SHIFT_MEGABYTE-SHIFT_BYTE)
1.1 djm 84:
85: /*
1.7 djm 86: * Using virtual memory can cause thrashing. This should be the largest
87: * number that is supported without a large amount of disk activity --
88: * that would increase the run time from hours to days or weeks!
89: */
1.9 deraadt 90: #define LARGE_MINIMUM (8UL) /* megabytes */
1.7 djm 91:
92: /*
93: * Do not increase this number beyond the unsigned integer bit size.
94: * Due to a multiple of 4, it must be LESS than 128 (yielding 2**30 bits).
95: */
1.9 deraadt 96: #define LARGE_MAXIMUM (127UL) /* megabytes */
1.7 djm 97:
98: /*
1.1 djm 99: * Constant: when used with 32-bit integers, the largest sieve prime
100: * has to be less than 2**32.
101: */
1.9 deraadt 102: #define SMALL_MAXIMUM (0xffffffffUL)
1.1 djm 103:
104: /* Constant: can sieve all primes less than 2**32, as 65537**2 > 2**32-1. */
1.9 deraadt 105: #define TINY_NUMBER (1UL<<16)
1.1 djm 106:
107: /* Ensure enough bit space for testing 2*q. */
1.12 djm 108: #define TEST_MAXIMUM (1UL<<16)
109: #define TEST_MINIMUM (QSIZE_MINIMUM + 1)
110: /* real TEST_MINIMUM (1UL << (SHIFT_WORD - TEST_POWER)) */
111: #define TEST_POWER (3) /* 2**n, n < SHIFT_WORD */
1.1 djm 112:
113: /* bit operations on 32-bit words */
1.12 djm 114: #define BIT_CLEAR(a,n) ((a)[(n)>>SHIFT_WORD] &= ~(1L << ((n) & 31)))
115: #define BIT_SET(a,n) ((a)[(n)>>SHIFT_WORD] |= (1L << ((n) & 31)))
116: #define BIT_TEST(a,n) ((a)[(n)>>SHIFT_WORD] & (1L << ((n) & 31)))
1.1 djm 117:
118: /*
119: * Prime testing defines
120: */
121:
1.7 djm 122: /* Minimum number of primality tests to perform */
1.12 djm 123: #define TRIAL_MINIMUM (4)
1.7 djm 124:
1.1 djm 125: /*
126: * Sieving data (XXX - move to struct)
127: */
128:
129: /* sieve 2**16 */
130: static u_int32_t *TinySieve, tinybits;
131:
132: /* sieve 2**30 in 2**16 parts */
133: static u_int32_t *SmallSieve, smallbits, smallbase;
134:
135: /* sieve relative to the initial value */
136: static u_int32_t *LargeSieve, largewords, largetries, largenumbers;
137: static u_int32_t largebits, largememory; /* megabytes */
138: static BIGNUM *largebase;
139:
1.11 avsm 140: int gen_candidates(FILE *, u_int32_t, u_int32_t, BIGNUM *);
1.26 dtucker 141: int prime_test(FILE *, FILE *, u_int32_t, u_int32_t, char *, unsigned long,
142: unsigned long);
1.1 djm 143:
144: /*
145: * print moduli out in consistent form,
146: */
147: static int
148: qfileout(FILE * ofile, u_int32_t otype, u_int32_t otests, u_int32_t otries,
149: u_int32_t osize, u_int32_t ogenerator, BIGNUM * omodulus)
150: {
151: struct tm *gtm;
152: time_t time_now;
153: int res;
154:
155: time(&time_now);
156: gtm = gmtime(&time_now);
1.2 djm 157:
1.1 djm 158: res = fprintf(ofile, "%04d%02d%02d%02d%02d%02d %u %u %u %u %x ",
159: gtm->tm_year + 1900, gtm->tm_mon + 1, gtm->tm_mday,
160: gtm->tm_hour, gtm->tm_min, gtm->tm_sec,
161: otype, otests, otries, osize, ogenerator);
162:
163: if (res < 0)
164: return (-1);
165:
166: if (BN_print_fp(ofile, omodulus) < 1)
167: return (-1);
168:
169: res = fprintf(ofile, "\n");
170: fflush(ofile);
171:
172: return (res > 0 ? 0 : -1);
173: }
174:
175:
176: /*
177: ** Sieve p's and q's with small factors
178: */
179: static void
180: sieve_large(u_int32_t s)
181: {
182: u_int32_t r, u;
183:
1.5 djm 184: debug3("sieve_large %u", s);
1.1 djm 185: largetries++;
186: /* r = largebase mod s */
187: r = BN_mod_word(largebase, s);
188: if (r == 0)
189: u = 0; /* s divides into largebase exactly */
190: else
191: u = s - r; /* largebase+u is first entry divisible by s */
192:
193: if (u < largebits * 2) {
194: /*
195: * The sieve omits p's and q's divisible by 2, so ensure that
196: * largebase+u is odd. Then, step through the sieve in
197: * increments of 2*s
198: */
199: if (u & 0x1)
200: u += s; /* Make largebase+u odd, and u even */
201:
202: /* Mark all multiples of 2*s */
203: for (u /= 2; u < largebits; u += s)
204: BIT_SET(LargeSieve, u);
205: }
206:
207: /* r = p mod s */
208: r = (2 * r + 1) % s;
209: if (r == 0)
210: u = 0; /* s divides p exactly */
211: else
212: u = s - r; /* p+u is first entry divisible by s */
213:
214: if (u < largebits * 4) {
215: /*
216: * The sieve omits p's divisible by 4, so ensure that
217: * largebase+u is not. Then, step through the sieve in
218: * increments of 4*s
219: */
220: while (u & 0x3) {
221: if (SMALL_MAXIMUM - u < s)
222: return;
223: u += s;
224: }
225:
226: /* Mark all multiples of 4*s */
227: for (u /= 4; u < largebits; u += s)
228: BIT_SET(LargeSieve, u);
229: }
230: }
231:
232: /*
1.6 djm 233: * list candidates for Sophie-Germain primes (where q = (p-1)/2)
1.1 djm 234: * to standard output.
235: * The list is checked against small known primes (less than 2**30).
236: */
237: int
1.11 avsm 238: gen_candidates(FILE *out, u_int32_t memory, u_int32_t power, BIGNUM *start)
1.1 djm 239: {
240: BIGNUM *q;
241: u_int32_t j, r, s, t;
242: u_int32_t smallwords = TINY_NUMBER >> 6;
243: u_int32_t tinywords = TINY_NUMBER >> 6;
244: time_t time_start, time_stop;
1.11 avsm 245: u_int32_t i;
246: int ret = 0;
1.1 djm 247:
248: largememory = memory;
249:
1.7 djm 250: if (memory != 0 &&
1.12 djm 251: (memory < LARGE_MINIMUM || memory > LARGE_MAXIMUM)) {
1.7 djm 252: error("Invalid memory amount (min %ld, max %ld)",
253: LARGE_MINIMUM, LARGE_MAXIMUM);
254: return (-1);
255: }
256:
1.1 djm 257: /*
1.2 djm 258: * Set power to the length in bits of the prime to be generated.
259: * This is changed to 1 less than the desired safe prime moduli p.
260: */
1.1 djm 261: if (power > TEST_MAXIMUM) {
262: error("Too many bits: %u > %lu", power, TEST_MAXIMUM);
263: return (-1);
264: } else if (power < TEST_MINIMUM) {
265: error("Too few bits: %u < %u", power, TEST_MINIMUM);
266: return (-1);
267: }
268: power--; /* decrement before squaring */
269:
270: /*
1.2 djm 271: * The density of ordinary primes is on the order of 1/bits, so the
272: * density of safe primes should be about (1/bits)**2. Set test range
273: * to something well above bits**2 to be reasonably sure (but not
274: * guaranteed) of catching at least one safe prime.
1.1 djm 275: */
276: largewords = ((power * power) >> (SHIFT_WORD - TEST_POWER));
277:
278: /*
1.2 djm 279: * Need idea of how much memory is available. We don't have to use all
280: * of it.
1.1 djm 281: */
282: if (largememory > LARGE_MAXIMUM) {
283: logit("Limited memory: %u MB; limit %lu MB",
284: largememory, LARGE_MAXIMUM);
285: largememory = LARGE_MAXIMUM;
286: }
287:
288: if (largewords <= (largememory << SHIFT_MEGAWORD)) {
289: logit("Increased memory: %u MB; need %u bytes",
290: largememory, (largewords << SHIFT_BYTE));
291: largewords = (largememory << SHIFT_MEGAWORD);
292: } else if (largememory > 0) {
293: logit("Decreased memory: %u MB; want %u bytes",
294: largememory, (largewords << SHIFT_BYTE));
295: largewords = (largememory << SHIFT_MEGAWORD);
296: }
297:
1.13 djm 298: TinySieve = xcalloc(tinywords, sizeof(u_int32_t));
1.1 djm 299: tinybits = tinywords << SHIFT_WORD;
300:
1.13 djm 301: SmallSieve = xcalloc(smallwords, sizeof(u_int32_t));
1.1 djm 302: smallbits = smallwords << SHIFT_WORD;
303:
304: /*
305: * dynamically determine available memory
306: */
307: while ((LargeSieve = calloc(largewords, sizeof(u_int32_t))) == NULL)
308: largewords -= (1L << (SHIFT_MEGAWORD - 2)); /* 1/4 MB chunks */
309:
310: largebits = largewords << SHIFT_WORD;
311: largenumbers = largebits * 2; /* even numbers excluded */
312:
313: /* validation check: count the number of primes tried */
314: largetries = 0;
1.19 markus 315: if ((q = BN_new()) == NULL)
316: fatal("BN_new failed");
1.1 djm 317:
318: /*
1.2 djm 319: * Generate random starting point for subprime search, or use
320: * specified parameter.
1.1 djm 321: */
1.19 markus 322: if ((largebase = BN_new()) == NULL)
323: fatal("BN_new failed");
324: if (start == NULL) {
325: if (BN_rand(largebase, power, 1, 1) == 0)
326: fatal("BN_rand failed");
327: } else {
328: if (BN_copy(largebase, start) == NULL)
329: fatal("BN_copy: failed");
330: }
1.1 djm 331:
332: /* ensure odd */
1.19 markus 333: if (BN_set_bit(largebase, 0) == 0)
334: fatal("BN_set_bit: failed");
1.1 djm 335:
336: time(&time_start);
337:
1.2 djm 338: logit("%.24s Sieve next %u plus %u-bit", ctime(&time_start),
1.1 djm 339: largenumbers, power);
340: debug2("start point: 0x%s", BN_bn2hex(largebase));
341:
342: /*
1.2 djm 343: * TinySieve
344: */
1.1 djm 345: for (i = 0; i < tinybits; i++) {
346: if (BIT_TEST(TinySieve, i))
347: continue; /* 2*i+3 is composite */
348:
349: /* The next tiny prime */
350: t = 2 * i + 3;
351:
352: /* Mark all multiples of t */
353: for (j = i + t; j < tinybits; j += t)
354: BIT_SET(TinySieve, j);
355:
356: sieve_large(t);
357: }
358:
359: /*
1.2 djm 360: * Start the small block search at the next possible prime. To avoid
361: * fencepost errors, the last pass is skipped.
362: */
1.1 djm 363: for (smallbase = TINY_NUMBER + 3;
1.12 djm 364: smallbase < (SMALL_MAXIMUM - TINY_NUMBER);
365: smallbase += TINY_NUMBER) {
1.1 djm 366: for (i = 0; i < tinybits; i++) {
367: if (BIT_TEST(TinySieve, i))
368: continue; /* 2*i+3 is composite */
369:
370: /* The next tiny prime */
371: t = 2 * i + 3;
372: r = smallbase % t;
373:
374: if (r == 0) {
375: s = 0; /* t divides into smallbase exactly */
376: } else {
377: /* smallbase+s is first entry divisible by t */
378: s = t - r;
379: }
380:
381: /*
382: * The sieve omits even numbers, so ensure that
383: * smallbase+s is odd. Then, step through the sieve
384: * in increments of 2*t
385: */
386: if (s & 1)
387: s += t; /* Make smallbase+s odd, and s even */
388:
389: /* Mark all multiples of 2*t */
390: for (s /= 2; s < smallbits; s += t)
391: BIT_SET(SmallSieve, s);
392: }
393:
394: /*
1.2 djm 395: * SmallSieve
396: */
1.1 djm 397: for (i = 0; i < smallbits; i++) {
398: if (BIT_TEST(SmallSieve, i))
399: continue; /* 2*i+smallbase is composite */
400:
401: /* The next small prime */
402: sieve_large((2 * i) + smallbase);
403: }
404:
405: memset(SmallSieve, 0, smallwords << SHIFT_BYTE);
406: }
407:
408: time(&time_stop);
409:
410: logit("%.24s Sieved with %u small primes in %ld seconds",
411: ctime(&time_stop), largetries, (long) (time_stop - time_start));
412:
413: for (j = r = 0; j < largebits; j++) {
414: if (BIT_TEST(LargeSieve, j))
415: continue; /* Definitely composite, skip */
416:
417: debug2("test q = largebase+%u", 2 * j);
1.19 markus 418: if (BN_set_word(q, 2 * j) == 0)
419: fatal("BN_set_word failed");
420: if (BN_add(q, q, largebase) == 0)
421: fatal("BN_add failed");
1.21 djm 422: if (qfileout(out, MODULI_TYPE_SOPHIE_GERMAIN,
423: MODULI_TESTS_SIEVE, largetries,
424: (power - 1) /* MSB */, (0), q) == -1) {
1.1 djm 425: ret = -1;
426: break;
427: }
428:
429: r++; /* count q */
430: }
431:
432: time(&time_stop);
433:
1.27 djm 434: free(LargeSieve);
435: free(SmallSieve);
436: free(TinySieve);
1.1 djm 437:
438: logit("%.24s Found %u candidates", ctime(&time_stop), r);
439:
440: return (ret);
441: }
442:
1.23 dtucker 443: static void
444: write_checkpoint(char *cpfile, u_int32_t lineno)
445: {
446: FILE *fp;
1.30 ! deraadt 447: char tmp[PATH_MAX];
1.23 dtucker 448: int r;
449:
1.25 djm 450: r = snprintf(tmp, sizeof(tmp), "%s.XXXXXXXXXX", cpfile);
1.30 ! deraadt 451: if (r == -1 || r >= PATH_MAX) {
1.23 dtucker 452: logit("write_checkpoint: temp pathname too long");
453: return;
454: }
1.25 djm 455: if ((r = mkstemp(tmp)) == -1) {
456: logit("mkstemp(%s): %s", tmp, strerror(errno));
1.23 dtucker 457: return;
458: }
459: if ((fp = fdopen(r, "w")) == NULL) {
460: logit("write_checkpoint: fdopen: %s", strerror(errno));
1.29 doug 461: unlink(tmp);
1.23 dtucker 462: close(r);
463: return;
464: }
465: if (fprintf(fp, "%lu\n", (unsigned long)lineno) > 0 && fclose(fp) == 0
1.25 djm 466: && rename(tmp, cpfile) == 0)
1.23 dtucker 467: debug3("wrote checkpoint line %lu to '%s'",
468: (unsigned long)lineno, cpfile);
469: else
470: logit("failed to write to checkpoint file '%s': %s", cpfile,
471: strerror(errno));
472: }
473:
474: static unsigned long
475: read_checkpoint(char *cpfile)
476: {
477: FILE *fp;
478: unsigned long lineno = 0;
479:
480: if ((fp = fopen(cpfile, "r")) == NULL)
481: return 0;
482: if (fscanf(fp, "%lu\n", &lineno) < 1)
483: logit("Failed to load checkpoint from '%s'", cpfile);
484: else
485: logit("Loaded checkpoint from '%s' line %lu", cpfile, lineno);
486: fclose(fp);
487: return lineno;
488: }
489:
1.28 dtucker 490: static unsigned long
491: count_lines(FILE *f)
492: {
493: unsigned long count = 0;
494: char lp[QLINESIZE + 1];
495:
496: if (fseek(f, 0, SEEK_SET) != 0) {
497: debug("input file is not seekable");
498: return ULONG_MAX;
499: }
500: while (fgets(lp, QLINESIZE + 1, f) != NULL)
501: count++;
502: rewind(f);
503: debug("input file has %lu lines", count);
504: return count;
505: }
506:
507: static char *
508: fmt_time(time_t seconds)
509: {
510: int day, hr, min;
511: static char buf[128];
512:
513: min = (seconds / 60) % 60;
514: hr = (seconds / 60 / 60) % 24;
515: day = seconds / 60 / 60 / 24;
516: if (day > 0)
517: snprintf(buf, sizeof buf, "%dd %d:%02d", day, hr, min);
518: else
519: snprintf(buf, sizeof buf, "%d:%02d", hr, min);
520: return buf;
521: }
522:
523: static void
524: print_progress(unsigned long start_lineno, unsigned long current_lineno,
525: unsigned long end_lineno)
526: {
527: static time_t time_start, time_prev;
528: time_t time_now, elapsed;
529: unsigned long num_to_process, processed, remaining, percent, eta;
530: double time_per_line;
531: char *eta_str;
532:
533: time_now = monotime();
534: if (time_start == 0) {
535: time_start = time_prev = time_now;
536: return;
537: }
538: /* print progress after 1m then once per 5m */
539: if (time_now - time_prev < 5 * 60)
540: return;
541: time_prev = time_now;
542: elapsed = time_now - time_start;
543: processed = current_lineno - start_lineno;
544: remaining = end_lineno - current_lineno;
545: num_to_process = end_lineno - start_lineno;
546: time_per_line = (double)elapsed / processed;
547: /* if we don't know how many we're processing just report count+time */
548: time(&time_now);
549: if (end_lineno == ULONG_MAX) {
550: logit("%.24s processed %lu in %s", ctime(&time_now),
551: processed, fmt_time(elapsed));
552: return;
553: }
554: percent = 100 * processed / num_to_process;
555: eta = time_per_line * remaining;
556: eta_str = xstrdup(fmt_time(eta));
557: logit("%.24s processed %lu of %lu (%lu%%) in %s, ETA %s",
558: ctime(&time_now), processed, num_to_process, percent,
559: fmt_time(elapsed), eta_str);
560: free(eta_str);
561: }
562:
1.1 djm 563: /*
564: * perform a Miller-Rabin primality test
565: * on the list of candidates
566: * (checking both q and p)
567: * The result is a list of so-call "safe" primes
568: */
569: int
1.23 dtucker 570: prime_test(FILE *in, FILE *out, u_int32_t trials, u_int32_t generator_wanted,
1.26 dtucker 571: char *checkpoint_file, unsigned long start_lineno, unsigned long num_lines)
1.1 djm 572: {
573: BIGNUM *q, *p, *a;
574: BN_CTX *ctx;
575: char *cp, *lp;
576: u_int32_t count_in = 0, count_out = 0, count_possible = 0;
577: u_int32_t generator_known, in_tests, in_tries, in_type, in_size;
1.26 dtucker 578: unsigned long last_processed = 0, end_lineno;
1.1 djm 579: time_t time_start, time_stop;
580: int res;
1.7 djm 581:
582: if (trials < TRIAL_MINIMUM) {
583: error("Minimum primality trials is %d", TRIAL_MINIMUM);
584: return (-1);
585: }
1.1 djm 586:
1.28 dtucker 587: if (num_lines == 0)
588: end_lineno = count_lines(in);
589: else
590: end_lineno = start_lineno + num_lines;
591:
1.1 djm 592: time(&time_start);
593:
1.19 markus 594: if ((p = BN_new()) == NULL)
595: fatal("BN_new failed");
596: if ((q = BN_new()) == NULL)
597: fatal("BN_new failed");
598: if ((ctx = BN_CTX_new()) == NULL)
599: fatal("BN_CTX_new failed");
1.1 djm 600:
601: debug2("%.24s Final %u Miller-Rabin trials (%x generator)",
602: ctime(&time_start), trials, generator_wanted);
603:
1.23 dtucker 604: if (checkpoint_file != NULL)
605: last_processed = read_checkpoint(checkpoint_file);
1.28 dtucker 606: last_processed = start_lineno = MAX(last_processed, start_lineno);
607: if (end_lineno == ULONG_MAX)
608: debug("process from line %lu from pipe", last_processed);
1.26 dtucker 609: else
1.28 dtucker 610: debug("process from line %lu to line %lu", last_processed,
611: end_lineno);
1.23 dtucker 612:
1.1 djm 613: res = 0;
614: lp = xmalloc(QLINESIZE + 1);
1.26 dtucker 615: while (fgets(lp, QLINESIZE + 1, in) != NULL && count_in < end_lineno) {
1.1 djm 616: count_in++;
1.28 dtucker 617: if (count_in <= last_processed) {
618: debug3("skipping line %u, before checkpoint or "
619: "specified start line", count_in);
620: continue;
621: }
622: if (checkpoint_file != NULL)
1.23 dtucker 623: write_checkpoint(checkpoint_file, count_in);
1.28 dtucker 624: print_progress(start_lineno, count_in, end_lineno);
1.20 ray 625: if (strlen(lp) < 14 || *lp == '!' || *lp == '#') {
1.1 djm 626: debug2("%10u: comment or short line", count_in);
627: continue;
628: }
629:
630: /* XXX - fragile parser */
631: /* time */
632: cp = &lp[14]; /* (skip) */
633:
634: /* type */
635: in_type = strtoul(cp, &cp, 10);
636:
637: /* tests */
638: in_tests = strtoul(cp, &cp, 10);
639:
1.21 djm 640: if (in_tests & MODULI_TESTS_COMPOSITE) {
1.1 djm 641: debug2("%10u: known composite", count_in);
642: continue;
643: }
1.5 djm 644:
1.1 djm 645: /* tries */
646: in_tries = strtoul(cp, &cp, 10);
647:
648: /* size (most significant bit) */
649: in_size = strtoul(cp, &cp, 10);
650:
651: /* generator (hex) */
652: generator_known = strtoul(cp, &cp, 16);
653:
654: /* Skip white space */
655: cp += strspn(cp, " ");
656:
657: /* modulus (hex) */
658: switch (in_type) {
1.21 djm 659: case MODULI_TYPE_SOPHIE_GERMAIN:
1.6 djm 660: debug2("%10u: (%u) Sophie-Germain", count_in, in_type);
1.1 djm 661: a = q;
1.19 markus 662: if (BN_hex2bn(&a, cp) == 0)
663: fatal("BN_hex2bn failed");
1.1 djm 664: /* p = 2*q + 1 */
1.19 markus 665: if (BN_lshift(p, q, 1) == 0)
666: fatal("BN_lshift failed");
667: if (BN_add_word(p, 1) == 0)
668: fatal("BN_add_word failed");
1.1 djm 669: in_size += 1;
670: generator_known = 0;
671: break;
1.21 djm 672: case MODULI_TYPE_UNSTRUCTURED:
673: case MODULI_TYPE_SAFE:
674: case MODULI_TYPE_SCHNORR:
675: case MODULI_TYPE_STRONG:
676: case MODULI_TYPE_UNKNOWN:
1.1 djm 677: debug2("%10u: (%u)", count_in, in_type);
678: a = p;
1.19 markus 679: if (BN_hex2bn(&a, cp) == 0)
680: fatal("BN_hex2bn failed");
1.1 djm 681: /* q = (p-1) / 2 */
1.19 markus 682: if (BN_rshift(q, p, 1) == 0)
683: fatal("BN_rshift failed");
1.1 djm 684: break;
1.5 djm 685: default:
686: debug2("Unknown prime type");
687: break;
1.1 djm 688: }
689:
690: /*
691: * due to earlier inconsistencies in interpretation, check
692: * the proposed bit size.
693: */
1.11 avsm 694: if ((u_int32_t)BN_num_bits(p) != (in_size + 1)) {
1.1 djm 695: debug2("%10u: bit size %u mismatch", count_in, in_size);
696: continue;
697: }
698: if (in_size < QSIZE_MINIMUM) {
699: debug2("%10u: bit size %u too short", count_in, in_size);
700: continue;
701: }
702:
1.21 djm 703: if (in_tests & MODULI_TESTS_MILLER_RABIN)
1.1 djm 704: in_tries += trials;
705: else
706: in_tries = trials;
1.5 djm 707:
1.1 djm 708: /*
709: * guess unknown generator
710: */
711: if (generator_known == 0) {
712: if (BN_mod_word(p, 24) == 11)
713: generator_known = 2;
714: else if (BN_mod_word(p, 12) == 5)
715: generator_known = 3;
716: else {
717: u_int32_t r = BN_mod_word(p, 10);
718:
1.5 djm 719: if (r == 3 || r == 7)
1.1 djm 720: generator_known = 5;
721: }
722: }
723: /*
724: * skip tests when desired generator doesn't match
725: */
726: if (generator_wanted > 0 &&
727: generator_wanted != generator_known) {
728: debug2("%10u: generator %d != %d",
729: count_in, generator_known, generator_wanted);
1.4 dtucker 730: continue;
731: }
732:
733: /*
734: * Primes with no known generator are useless for DH, so
735: * skip those.
736: */
737: if (generator_known == 0) {
738: debug2("%10u: no known generator", count_in);
1.1 djm 739: continue;
740: }
741:
742: count_possible++;
743:
744: /*
1.2 djm 745: * The (1/4)^N performance bound on Miller-Rabin is
746: * extremely pessimistic, so don't spend a lot of time
747: * really verifying that q is prime until after we know
748: * that p is also prime. A single pass will weed out the
1.1 djm 749: * vast majority of composite q's.
750: */
1.22 djm 751: if (BN_is_prime_ex(q, 1, ctx, NULL) <= 0) {
1.5 djm 752: debug("%10u: q failed first possible prime test",
1.1 djm 753: count_in);
754: continue;
755: }
1.2 djm 756:
1.1 djm 757: /*
1.2 djm 758: * q is possibly prime, so go ahead and really make sure
759: * that p is prime. If it is, then we can go back and do
760: * the same for q. If p is composite, chances are that
1.1 djm 761: * will show up on the first Rabin-Miller iteration so it
762: * doesn't hurt to specify a high iteration count.
763: */
1.22 djm 764: if (!BN_is_prime_ex(p, trials, ctx, NULL)) {
1.5 djm 765: debug("%10u: p is not prime", count_in);
1.1 djm 766: continue;
767: }
768: debug("%10u: p is almost certainly prime", count_in);
769:
770: /* recheck q more rigorously */
1.22 djm 771: if (!BN_is_prime_ex(q, trials - 1, ctx, NULL)) {
1.1 djm 772: debug("%10u: q is not prime", count_in);
773: continue;
774: }
775: debug("%10u: q is almost certainly prime", count_in);
776:
1.21 djm 777: if (qfileout(out, MODULI_TYPE_SAFE,
778: in_tests | MODULI_TESTS_MILLER_RABIN,
1.1 djm 779: in_tries, in_size, generator_known, p)) {
780: res = -1;
781: break;
782: }
783:
784: count_out++;
785: }
786:
787: time(&time_stop);
1.27 djm 788: free(lp);
1.1 djm 789: BN_free(p);
790: BN_free(q);
791: BN_CTX_free(ctx);
1.23 dtucker 792:
793: if (checkpoint_file != NULL)
794: unlink(checkpoint_file);
1.1 djm 795:
796: logit("%.24s Found %u safe primes of %u candidates in %ld seconds",
1.2 djm 797: ctime(&time_stop), count_out, count_possible,
1.1 djm 798: (long) (time_stop - time_start));
799:
800: return (res);
801: }
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