c4f2d992 |
1 | /* -*-c-*- |
2 | * |
fe59d3d7 |
3 | * $Id: keygen.c,v 1.6 2003/09/17 13:17:23 mdw Exp $ |
c4f2d992 |
4 | * |
5 | * Key generation |
6 | * |
c758e654 |
7 | * (c) 1998 EBI |
c4f2d992 |
8 | */ |
9 | |
03f996bd |
10 | /*----- Licensing notice --------------------------------------------------* |
c4f2d992 |
11 | * |
12 | * This file is part of `become' |
13 | * |
14 | * `Become' is free software; you can redistribute it and/or modify |
15 | * it under the terms of the GNU General Public License as published by |
16 | * the Free Software Foundation; either version 2 of the License, or |
17 | * (at your option) any later version. |
18 | * |
19 | * `Become' is distributed in the hope that it will be useful, |
20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
22 | * GNU General Public License for more details. |
23 | * |
24 | * You should have received a copy of the GNU General Public License |
03f996bd |
25 | * along with `become'; if not, write to the Free Software Foundation, |
26 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
c4f2d992 |
27 | */ |
28 | |
29 | /*----- Revision history --------------------------------------------------* |
30 | * |
31 | * $Log: keygen.c,v $ |
fe59d3d7 |
32 | * Revision 1.6 2003/09/17 13:17:23 mdw |
33 | * Make it build\! |
34 | * |
c758e654 |
35 | * Revision 1.5 1998/01/12 16:46:05 mdw |
36 | * Fix copyright date. |
37 | * |
27d41d48 |
38 | * Revision 1.4 1997/12/08 15:29:27 mdw |
39 | * Major update: make random number sources configurable. Generate |
40 | * warnings if there isn't enough randomness available. |
41 | * |
42 | * Revision 1.3 1997/09/17 15:29:28 mdw |
b80cbed5 |
43 | * Mix the noise from the key timings with some other environmental noise |
44 | * (obtained from `noise_acquire') for a little bit more randomness. |
45 | * |
03f996bd |
46 | * Revision 1.2 1997/08/04 10:24:23 mdw |
47 | * Sources placed under CVS control. |
48 | * |
49 | * Revision 1.1 1997/07/21 13:47:48 mdw |
c4f2d992 |
50 | * Initial revision |
51 | * |
52 | */ |
53 | |
54 | /*----- Header files ------------------------------------------------------*/ |
55 | |
56 | /* --- ANSI headers --- */ |
57 | |
58 | #include <ctype.h> |
59 | #include <errno.h> |
60 | #include <signal.h> |
61 | #include <stdio.h> |
62 | #include <stdlib.h> |
63 | #include <string.h> |
fe59d3d7 |
64 | #include <time.h> |
c4f2d992 |
65 | |
66 | /* --- Unix headers --- */ |
67 | |
68 | #include <sys/types.h> |
69 | #include <sys/time.h> |
70 | #include <fcntl.h> |
71 | |
72 | #include <termios.h> |
73 | #include <unistd.h> |
74 | |
75 | /* --- Local headers --- */ |
76 | |
77 | #include "config.h" |
c4f2d992 |
78 | #include "mdwopt.h" |
b80cbed5 |
79 | #include "noise.h" |
80 | #include "rand.h" |
81 | #include "tx.h" |
c4f2d992 |
82 | #include "utils.h" |
83 | |
84 | /*----- Static variables --------------------------------------------------*/ |
85 | |
86 | static struct termios kg__raw, kg__old; /* Terminal settings */ |
87 | static int kg__tty; /* File handle for the terminal */ |
88 | static FILE *kg__ttyfp; /* Stream pointer for terminal */ |
89 | static unsigned int kg__flags; /* Various interesting flags */ |
90 | |
91 | enum { |
92 | kgFlag__cbreak = 1 /* Terminal is in cbreak mode */ |
93 | }; |
94 | |
95 | /*----- Main code ---------------------------------------------------------*/ |
96 | |
97 | /* --- @kg__cbreak@ --- * |
98 | * |
99 | * Arguments: --- |
100 | * |
101 | * Returns: --- |
102 | * |
103 | * Use: Makes the terminal return characters as soon as they're |
104 | * asked for. |
105 | */ |
106 | |
107 | void kg__cbreak(void) |
108 | { |
109 | /* --- Don't do this if I don't have to --- */ |
110 | |
111 | if (kg__flags & kgFlag__cbreak) |
112 | return; |
113 | |
114 | /* --- Fetch the old attributes, and remember them --- */ |
115 | |
116 | if (tcgetattr(kg__tty, &kg__old)) |
117 | die("couldn't read terminal attributes: %s", strerror(errno)); |
118 | memcpy(&kg__raw, &kg__old, sizeof(kg__raw)); |
119 | |
120 | /* --- Now modify them for raw mode --- */ |
121 | |
122 | kg__raw.c_lflag &= ~(ICANON | ECHO); |
123 | kg__raw.c_cc[VTIME] = 0; |
124 | kg__raw.c_cc[VMIN] = 1; |
125 | |
126 | /* --- Remember the new state, and away we go --- */ |
127 | |
128 | kg__flags |= kgFlag__cbreak; |
129 | if (tcsetattr(kg__tty, TCSAFLUSH, &kg__raw)) |
130 | die("couldn't set terminal attributes: %s", strerror(errno)); |
131 | } |
132 | |
133 | /* --- @kg__crepair@ --- * |
134 | * |
135 | * Arguments: --- |
136 | * |
137 | * Returns: --- |
138 | * |
139 | * Use: Unbreaks a cbroken tty. Obvious, innit? |
140 | */ |
141 | |
142 | static void kg__crepair(void) |
143 | { |
144 | /* --- Don't do this if I don't have to --- */ |
145 | |
146 | if (~kg__flags & kgFlag__cbreak) |
147 | return; |
148 | |
149 | /* --- Reset the old attributes --- */ |
150 | |
151 | tcsetattr(kg__tty, TCSAFLUSH, &kg__old); |
152 | kg__flags &= ~kgFlag__cbreak; |
153 | } |
154 | |
155 | /* --- @kg__signal@ --- * |
156 | * |
157 | * Arguments: @int sig@ = signal number |
158 | * |
159 | * Returns: --- |
160 | * |
161 | * Use: Tidies up if I get a signal. |
162 | */ |
163 | |
164 | static void kg__signal(int sig) |
165 | { |
166 | kg__crepair(); |
167 | signal(sig, SIG_DFL); |
168 | raise(sig); |
169 | } |
170 | |
171 | /* --- @kgFmt__binary@ --- * |
172 | * |
173 | * Arguments: @unsigned char *k@ = pointer to key buffer |
174 | * @size_t bits@ = number of bits to write |
175 | * @FILE *fp@ = stream to write on |
176 | * |
177 | * Returns: --- |
178 | * |
179 | * Use: Writes bits on a stream. |
180 | */ |
181 | |
182 | static void kgFmt__binary(unsigned char *k, size_t bits, FILE *fp) |
183 | { |
184 | fwrite(k, 1, bits / 8, fp); |
185 | } |
186 | |
187 | /* --- @kgFmt__base64@ --- * |
188 | * |
189 | * Arguments: @unsigned char *k@ = pointer to key buffer |
190 | * @size_t bits@ = number of bits to write |
191 | * @FILE *fp@ = stream to write on |
192 | * |
193 | * Returns: --- |
194 | * |
195 | * Use: Writes bits on a stream in an encoded way. |
196 | */ |
197 | |
198 | static void kgFmt__base64(unsigned char *k, size_t bits, FILE *fp) |
199 | { |
200 | static const char xlt[64] = { "ABCDEFGHIJKLMNOPQRSTUVWXYZ" |
201 | "abcdefghijklmnopqrstuvwxyz" |
202 | "0123456789+/" }; |
203 | unsigned long b; |
204 | int ll = 0; |
205 | |
206 | while (bits > 24) { |
207 | b = ((k[0] & 0xffu) << 16) | ((k[1] & 0xffu) << 8) | (k[2] & 0xffu); |
208 | k += 3; |
209 | bits -= 24; |
210 | putc(xlt[(b >> 18) & 0x3fu], fp); |
211 | putc(xlt[(b >> 12) & 0x3fu], fp); |
212 | putc(xlt[(b >> 6) & 0x3fu], fp); |
213 | putc(xlt[(b >> 0) & 0x3fu], fp); |
214 | if ((ll += 4) > 70) { |
215 | putc('\n', fp); |
216 | ll = 0; |
217 | } |
218 | } |
219 | |
220 | b = 0; |
221 | switch (bits) { |
222 | case 24: |
223 | b = *k++ & 0xffu; |
224 | case 16: |
225 | b = (b << 8) | (*k++ & 0xffu); |
226 | case 8: |
227 | b = (b << 8) | (*k++ & 0xffu); |
228 | } |
229 | b <<= (24 - bits); |
230 | putc(xlt[(b >> 18) & 0x3fu], fp); |
231 | putc(xlt[(b >> 12) & 0x3fu], fp); |
232 | switch (bits) { |
233 | case 24: |
234 | putc(xlt[(b >> 6) & 0x3fu], fp); |
235 | putc(xlt[(b >> 0) & 0x3fu], fp); |
236 | break; |
237 | case 16: |
238 | putc(xlt[(b >> 6) & 0x3fu], fp); |
239 | putc('=', fp); |
240 | break; |
241 | case 8: |
242 | fputs("==", fp); |
243 | break; |
244 | } |
245 | |
246 | putc('\n', fp); |
247 | } |
248 | |
249 | /* --- @kg__gen@ --- * |
250 | * |
251 | * Arguments: @unsigned char *ui@ = pointer to array to fill in |
252 | * @size_t sz@ = number of bits to generate |
253 | * |
254 | * Returns: --- |
255 | * |
256 | * Use: Uses key timings to generate random numbers. Maybe. |
257 | */ |
258 | |
259 | static void kg__gen(unsigned char *ui, size_t sz) |
260 | { |
261 | int bits = 32 < sz ? 32 : sz; |
262 | size_t wsz = (sz + 31u) & ~31u; |
263 | unsigned long last, ldiff = 0; |
264 | unsigned long a = 0; |
265 | unsigned long fact = 1000000 / CLOCKS_PER_SEC; |
266 | |
267 | fprintf(kg__ttyfp, |
03f996bd |
268 | "I need to get %lu random bits; I'll do this by timing your keypresses.\n" |
c4f2d992 |
269 | "Please type some arbitrary text until I say `done'.\n", |
03f996bd |
270 | (unsigned long)sz); |
c4f2d992 |
271 | |
272 | { |
273 | struct timeval tv; |
274 | gettimeofday(&tv, 0); |
275 | last = tv.tv_usec / fact + tv.tv_sec * fact; |
276 | } |
277 | |
278 | while (sz) { |
279 | int useful; |
280 | uint_32 orr, xor; |
281 | |
282 | /* --- Print current status --- */ |
283 | |
03f996bd |
284 | fprintf(kg__ttyfp, "\r%5lu...", (unsigned long)sz); |
c4f2d992 |
285 | fflush(kg__ttyfp); |
286 | |
287 | /* --- Read the next character --- */ |
288 | |
289 | { |
290 | char buff[16]; |
291 | if (read(kg__tty, buff, sizeof(buff)) < 0) |
292 | die("couldn't read from terminal: %s", strerror(errno)); |
293 | } |
294 | |
295 | /* --- Fiddle with times --- * |
296 | * |
297 | * Read the time now. Turn it into 32 bits of useful information, and |
298 | * find the difference between that and the previous time. Compare this |
299 | * with the difference between the previous pair of keypresses. |
300 | */ |
301 | |
302 | { |
303 | struct timeval tv; |
304 | uint_32 n, nd; |
305 | |
306 | gettimeofday(&tv, 0); |
307 | n = tv.tv_usec / fact + tv.tv_sec * fact; |
308 | if (!ldiff) { |
309 | ldiff = n - last; |
310 | last = n; |
311 | continue; |
312 | } |
313 | nd = n - last; |
314 | orr = nd | ldiff; |
315 | xor = nd ^ ldiff; |
316 | D( printf("\nlast = %08lx, next = %08lx, ldiff = %08lx, nd = %08lx\n", |
317 | (unsigned long)last, (unsigned long)n, |
318 | (unsigned long)ldiff, (unsigned long)nd); |
319 | printf("xor = %08lx\n", (unsigned long)xor); ) |
320 | ldiff = nd; |
321 | last = n; |
322 | } |
323 | |
324 | /* --- Find the useful bits in this value --- * |
325 | * |
326 | * Find the least significant set bit in @bowl@ and chop it off. Then |
327 | * find the most significant set bit and chop that off two. The rest is |
328 | * probably interesting. |
329 | */ |
330 | |
331 | { |
332 | unsigned long i; |
333 | |
334 | if (!orr || !xor) |
335 | continue; /* erk! */ |
336 | |
337 | useful = 30; |
338 | |
339 | i = 0x80000000ul; |
340 | if (xor & i) { |
341 | while (i && (xor & i) != 0) { |
342 | i >>= 1; |
343 | useful--; |
344 | } |
345 | } else { |
346 | while (i && (xor & i) == 0) { |
347 | i >>= 1; |
348 | useful--; |
349 | } |
350 | } |
351 | xor &= ~-i; |
352 | |
353 | while ((orr & 1) == 0) { |
354 | useful--; |
355 | orr >>= 1; |
356 | xor >>= 1; |
357 | } |
358 | xor >>= 1; |
359 | |
360 | if (useful < 1) |
361 | continue; |
362 | } |
363 | |
364 | /* --- Now add the bits in the mixing bowl to my stash --- * |
365 | * |
366 | * There are two cases: |
367 | * |
368 | * 1. I have more bits than will fit into the accumulator. Then I must |
369 | * put as many bits into the accumulator as will fit, store the |
370 | * accumulator, and remove the spent bits. |
371 | * |
372 | * 2. I have too few bits to fit in the accumulator. Then shift them |
373 | * in and return. |
374 | */ |
375 | |
376 | while (sz && useful) { |
377 | |
378 | D( printf("got %i bits, need %i/%i: %8lx\n", |
379 | useful, bits, sz, (unsigned long)xor); ) |
380 | |
381 | if (useful >= bits) { |
382 | |
383 | D( printf("shifted acc = %08lx\n" |
384 | " new bits = %08lx\n" |
385 | " result = %08lx\n", |
386 | (unsigned long)(a << bits), |
387 | (unsigned long)(xor >> (useful - bits)), |
388 | (unsigned long)((a << bits) | (xor >> (useful - bits)))); ) |
389 | |
390 | a = (a << bits) | (xor >> (useful - bits)); |
391 | |
392 | sz -= bits; |
393 | wsz -= bits; |
394 | useful -= bits; |
395 | |
396 | if (sz == 0) { |
397 | a <<= wsz; |
398 | bits = 32 - wsz; |
399 | } else |
400 | bits = 32; |
401 | |
402 | while (bits > 0) { |
403 | D( printf("writing %02x\n", (a >> 24) & 0xffu); ) |
404 | *ui++ = (a >> 24) & 0xffu; |
405 | a <<= 8; |
406 | bits -= 8; |
407 | } |
408 | a = 0; |
409 | |
410 | bits = 32 < sz ? 32 : sz; |
411 | |
412 | } else { |
413 | |
414 | D( printf("shifted acc = %08lx\n" |
415 | " new bits = %08lx\n" |
416 | " result = %08lx\n", |
417 | (unsigned long)(a << useful), |
418 | (unsigned long)(xor), |
419 | (unsigned long)((a << useful) | (xor))); ) |
420 | a = (a << useful) | xor; |
421 | bits -= useful; |
422 | sz -= useful; |
423 | wsz -= useful; |
424 | useful = 0; |
425 | } |
426 | } |
427 | } |
428 | |
429 | fputs("\rDone! \n", kg__ttyfp); |
430 | putc('\a', kg__ttyfp); fflush(kg__ttyfp); |
431 | sleep(1); |
432 | } |
433 | |
434 | /* --- @main@ --- * |
435 | * |
436 | * Arguments: @int argc@ = number of arguments |
437 | * @char *argv[]@ = array of arguments |
438 | * |
439 | * Returns: Zero if it worked, nonzero if it didn't. |
440 | * |
441 | * Use: Generates random numbers from the keyboard. |
442 | */ |
443 | |
444 | int main(int argc, char *argv[]) |
445 | { |
446 | unsigned char *uip; |
447 | size_t sz = 128; |
27d41d48 |
448 | size_t keybits = 0; |
449 | unsigned f = 0; |
c4f2d992 |
450 | const char *file = 0; |
451 | FILE *fp; |
452 | |
27d41d48 |
453 | enum { |
454 | f_envNoise = 1, |
455 | f_keyTimer = 2 |
456 | }; |
457 | |
c4f2d992 |
458 | /* --- Formats table --- */ |
459 | |
460 | static struct { |
461 | const char *name; |
462 | void (*proc)(unsigned char *k, size_t bits, FILE *fp); |
463 | } format[] = { |
464 | { "tx", tx_putBits }, |
465 | { "hex", tx_putBits }, |
466 | { "binary", kgFmt__binary }, |
467 | { "base64", kgFmt__base64 }, |
468 | { 0, 0 } |
469 | }; |
470 | |
471 | void (*fmt)(unsigned char *, size_t, FILE *) = tx_putBits; |
472 | |
473 | /* --- Explain who I am --- */ |
474 | |
475 | ego(argv[0]); |
476 | |
27d41d48 |
477 | f |= f_envNoise | f_keyTimer; |
478 | |
c4f2d992 |
479 | /* --- Read arguments --- */ |
480 | |
481 | for (;;) { |
482 | static struct option opts[] = { |
27d41d48 |
483 | { "help", 0, 0, 'h' }, |
484 | { "bits", gFlag_argReq, 0, 'b' }, |
485 | { "output", gFlag_argReq, 0, 'o' }, |
486 | { "format", gFlag_argReq, 0, 'f' }, |
487 | { "key-times", gFlag_negate|gFlag_argOpt, 0, 'k' }, |
488 | { "env-noise", gFlag_negate, 0, 'e' }, |
489 | { 0, 0, 0, 0 } |
c4f2d992 |
490 | }; |
491 | |
27d41d48 |
492 | int i = mdwopt(argc, argv, "hb:o:f:k+::e+", opts, 0, 0, gFlag_negation); |
c4f2d992 |
493 | |
494 | if (i < 0) |
495 | break; |
496 | switch (i) { |
497 | case 'h': |
498 | printf("" |
27d41d48 |
499 | "Usage: %s [-h] [-|+ek] [-b BITS] [-o FILE] [-f FORMAT]\n" |
c4f2d992 |
500 | "\n" |
27d41d48 |
501 | "Generates BITS (by default, 128) random bits. The resulting number is\n" |
502 | "written to FILE, or standard output.\n\n" |
503 | "Randomness is taken from key-timings and environmental noise, although\n" |
504 | "you can disable either (or both) of these sources.\n\n" |
505 | "Options provided are:\n\n" |
506 | "-h, --help Display this help text\n" |
507 | "-b, --bits=BITS\t Generate BITS random bits instead of 128\n" |
508 | "-o, --output=FILE Write bits to FILE, not standard output\n" |
509 | "-f, --format=FORMAT Write bits in FORMAT:\n" |
510 | " tx, hex Hexadecimal\n" |
511 | " binary Raw binary\n" |
512 | " base64 Base64-encoded binary\n" |
513 | "-e, --[no-]env-noise Do [not] read environmental noise\n" |
514 | "-k, --[no-]key-times[=BITS] Do [not] read key timing information\n" |
515 | " (only read BITS bits from key timings)\n", |
c4f2d992 |
516 | quis()); |
517 | exit(0); |
518 | break; |
519 | case 'b': |
520 | sz = atoi(optarg); |
521 | if (sz == 0) |
522 | die("bad number of bits (illegible or zero)"); |
523 | if (sz % 8) |
524 | die("can only generate a whole number of 8-bit bytes"); |
525 | break; |
526 | case 'o': |
527 | file = optarg; |
528 | break; |
529 | case 'f': |
530 | fmt = 0; |
531 | for (i = 0; format[i].name; i++) { |
532 | const char *p = format[i].name, *q = optarg; |
533 | for (;;) { |
534 | if (*q == 0) |
535 | break; |
536 | if (*p != *q) |
537 | break; |
538 | p++, q++; |
539 | } |
540 | if (!*q) { |
541 | if (fmt) |
542 | die("ambiguous format name: `%s'", optarg); |
543 | fmt = format[i].proc; |
544 | } |
545 | } |
546 | if (!fmt) |
547 | die("unknown format name: `%s'", optarg); |
548 | break; |
27d41d48 |
549 | case 'e': |
550 | f |= f_envNoise; |
551 | break; |
552 | case 'e' | gFlag_negated: |
553 | f &= ~f_envNoise; |
554 | break; |
555 | case 'k': |
556 | f |= f_keyTimer; |
557 | if (optarg) { |
558 | keybits = atoi(optarg); |
559 | if (keybits == 0) |
560 | die("bad number of bits (illegible or zero)"); |
561 | if (keybits % 8) |
562 | die("bad number of bits (must be multiple of 8)"); |
563 | } |
564 | else |
565 | keybits = 0; |
566 | break; |
567 | case 'k' | gFlag_negated: |
568 | f &= ~f_keyTimer; |
569 | break; |
c4f2d992 |
570 | case '?': |
571 | exit(1); |
572 | break; |
573 | } |
574 | } |
575 | |
27d41d48 |
576 | /* --- Check the sanity of this request --- */ |
577 | |
578 | { |
579 | size_t bits = 0; |
580 | |
581 | if (f & f_keyTimer) { |
582 | if (!keybits) |
583 | keybits = sz; |
584 | bits += keybits; |
585 | } |
586 | if (f & f_envNoise) |
587 | bits += 384; /* Estimate */ |
588 | |
589 | if (bits == 0) |
590 | die("no randomness sources given"); |
591 | if (bits < sz) |
592 | moan("warning: randomness may not be sufficiently high"); |
593 | } |
594 | |
c4f2d992 |
595 | if (optind < argc) { |
27d41d48 |
596 | fprintf(stderr, "Usage: %s [-opts]\n", quis()); |
c4f2d992 |
597 | exit(1); |
598 | } |
599 | |
600 | /* --- Allocate memory --- */ |
601 | |
27d41d48 |
602 | { |
603 | size_t buff = sz / 8; |
604 | if (f & f_keyTimer && keybits > sz) |
605 | buff = keybits / 8; |
606 | uip = xmalloc(buff); |
607 | } |
608 | |
609 | rand_clear(); |
610 | |
611 | /* --- Fetch randomness from key timings --- */ |
612 | |
613 | if (f & f_keyTimer) { |
614 | |
615 | /* --- Open the terminal --- * |
616 | * |
617 | * I'd like to be able to @fprintf@ to the terminal, so use @fopen@. |
618 | */ |
619 | |
620 | if ((kg__ttyfp = fopen("/dev/tty", "r+")) == 0) |
621 | die("couldn't open terminal: %s", strerror(errno)); |
622 | kg__tty = fileno(kg__ttyfp); |
c4f2d992 |
623 | |
27d41d48 |
624 | /* --- Tidy up nicely if I die --- */ |
c4f2d992 |
625 | |
27d41d48 |
626 | signal(SIGINT, kg__signal); |
627 | signal(SIGTERM, kg__signal); |
628 | atexit(kg__crepair); |
629 | |
630 | /* --- Put the terminal into cbreak, read the key, and restore --- */ |
631 | |
632 | kg__cbreak(); |
633 | kg__gen(uip, keybits); |
634 | kg__crepair(); |
635 | rand_add(uip, keybits / 8); |
636 | rand_churn(); |
637 | } |
638 | |
639 | /* --- Find some noise from the environment too --- */ |
640 | |
641 | if (f & f_envNoise) { |
642 | noise_acquire(); |
643 | rand_churn(); |
644 | } |
645 | |
646 | /* --- Now write the number and exit --- */ |
647 | |
648 | rand_extract(uip, sz / 8); |
649 | D( fputs("*** ", fp); tx_putBits(uip, sz, stdout); ) |
c4f2d992 |
650 | |
651 | /* --- Open the output file, if one is specified --- */ |
652 | |
653 | if (file) { |
654 | int fd; |
655 | |
656 | /* --- Open the file oddly --- * |
657 | * |
658 | * There's a good reason for this. I want to be able to @fprintf@ (for |
659 | * the benefit of @tx_putWords@ mainly) but I also want to ensure that |
660 | * only the user has read permissions for the file. So I'll use @open@ |
27d41d48 |
661 | * with an appropriate mode and then @fdopen@ the file descriptor to |
662 | * get a stream. Yuk. |
c4f2d992 |
663 | */ |
664 | |
665 | if ((fd = open(file, O_WRONLY | O_CREAT | O_TRUNC, 0600)) < 0) |
666 | die("couldn't open output file: %s", strerror(errno)); |
667 | if ((fp = fdopen(fd, "w")) == 0) |
668 | die("couldn't attach stream to output file: %s", strerror(errno)); |
669 | } else |
670 | fp = stdout; |
671 | |
c4f2d992 |
672 | fmt(uip, sz, fp); |
673 | if (file) |
674 | fclose(fp); |
675 | memset(uip, 0, sz / 8); /* Burn temporary buffer */ |
b80cbed5 |
676 | rand_clear(); |
c4f2d992 |
677 | return (0); |
678 | } |
679 | |
680 | /*----- That's all, folks -------------------------------------------------*/ |