1 | /* |
2 | * Copyright 1999-2017 The OpenSSL Project Authors. All Rights Reserved. |
3 | * |
4 | * Licensed under the Apache License 2.0 (the "License"). You may not use |
5 | * this file except in compliance with the License. You can obtain a copy |
6 | * in the file LICENSE in the source distribution or at |
7 | * https://www.openssl.org/source/license.html |
8 | */ |
9 | |
10 | /*- |
11 | * This is an implementation of the ASN1 Time structure which is: |
12 | * Time ::= CHOICE { |
13 | * utcTime UTCTime, |
14 | * generalTime GeneralizedTime } |
15 | */ |
16 | |
17 | #include <stdio.h> |
18 | #include <time.h> |
19 | #include "crypto/ctype.h" |
20 | #include "internal/cryptlib.h" |
21 | #include <openssl/asn1t.h> |
22 | #include "asn1_local.h" |
23 | |
24 | IMPLEMENT_ASN1_MSTRING(ASN1_TIME, B_ASN1_TIME) |
25 | |
26 | IMPLEMENT_ASN1_FUNCTIONS(ASN1_TIME) |
27 | |
28 | static int is_utc(const int year) |
29 | { |
30 | if (50 <= year && year <= 149) |
31 | return 1; |
32 | return 0; |
33 | } |
34 | |
35 | static int leap_year(const int year) |
36 | { |
37 | if (year % 400 == 0 || (year % 100 != 0 && year % 4 == 0)) |
38 | return 1; |
39 | return 0; |
40 | } |
41 | |
42 | /* |
43 | * Compute the day of the week and the day of the year from the year, month |
44 | * and day. The day of the year is straightforward, the day of the week uses |
45 | * a form of Zeller's congruence. For this months start with March and are |
46 | * numbered 4 through 15. |
47 | */ |
48 | static void determine_days(struct tm *tm) |
49 | { |
50 | static const int ydays[12] = { |
51 | 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 |
52 | }; |
53 | int y = tm->tm_year + 1900; |
54 | int m = tm->tm_mon; |
55 | int d = tm->tm_mday; |
56 | int c; |
57 | |
58 | tm->tm_yday = ydays[m] + d - 1; |
59 | if (m >= 2) { |
60 | /* March and onwards can be one day further into the year */ |
61 | tm->tm_yday += leap_year(y); |
62 | m += 2; |
63 | } else { |
64 | /* Treat January and February as part of the previous year */ |
65 | m += 14; |
66 | y--; |
67 | } |
68 | c = y / 100; |
69 | y %= 100; |
70 | /* Zeller's congruence */ |
71 | tm->tm_wday = (d + (13 * m) / 5 + y + y / 4 + c / 4 + 5 * c + 6) % 7; |
72 | } |
73 | |
74 | int asn1_time_to_tm(struct tm *tm, const ASN1_TIME *d) |
75 | { |
76 | static const int min[9] = { 0, 0, 1, 1, 0, 0, 0, 0, 0 }; |
77 | static const int max[9] = { 99, 99, 12, 31, 23, 59, 59, 12, 59 }; |
78 | static const int mdays[12] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }; |
79 | char *a; |
80 | int n, i, i2, l, o, min_l = 11, strict = 0, end = 6, btz = 5, md; |
81 | struct tm tmp; |
82 | #if defined(CHARSET_EBCDIC) |
83 | const char upper_z = 0x5A, num_zero = 0x30, period = 0x2E, minus = 0x2D, plus = 0x2B; |
84 | #else |
85 | const char upper_z = 'Z', num_zero = '0', period = '.', minus = '-', plus = '+'; |
86 | #endif |
87 | /* |
88 | * ASN1_STRING_FLAG_X509_TIME is used to enforce RFC 5280 |
89 | * time string format, in which: |
90 | * |
91 | * 1. "seconds" is a 'MUST' |
92 | * 2. "Zulu" timezone is a 'MUST' |
93 | * 3. "+|-" is not allowed to indicate a time zone |
94 | */ |
95 | if (d->type == V_ASN1_UTCTIME) { |
96 | if (d->flags & ASN1_STRING_FLAG_X509_TIME) { |
97 | min_l = 13; |
98 | strict = 1; |
99 | } |
100 | } else if (d->type == V_ASN1_GENERALIZEDTIME) { |
101 | end = 7; |
102 | btz = 6; |
103 | if (d->flags & ASN1_STRING_FLAG_X509_TIME) { |
104 | min_l = 15; |
105 | strict = 1; |
106 | } else { |
107 | min_l = 13; |
108 | } |
109 | } else { |
110 | return 0; |
111 | } |
112 | |
113 | l = d->length; |
114 | a = (char *)d->data; |
115 | o = 0; |
116 | memset(&tmp, 0, sizeof(tmp)); |
117 | |
118 | /* |
119 | * GENERALIZEDTIME is similar to UTCTIME except the year is represented |
120 | * as YYYY. This stuff treats everything as a two digit field so make |
121 | * first two fields 00 to 99 |
122 | */ |
123 | |
124 | if (l < min_l) |
125 | goto err; |
126 | for (i = 0; i < end; i++) { |
127 | if (!strict && (i == btz) && ((a[o] == upper_z) || (a[o] == plus) || (a[o] == minus))) { |
128 | i++; |
129 | break; |
130 | } |
131 | if (!ascii_isdigit(a[o])) |
132 | goto err; |
133 | n = a[o] - num_zero; |
134 | /* incomplete 2-digital number */ |
135 | if (++o == l) |
136 | goto err; |
137 | |
138 | if (!ascii_isdigit(a[o])) |
139 | goto err; |
140 | n = (n * 10) + a[o] - num_zero; |
141 | /* no more bytes to read, but we haven't seen time-zone yet */ |
142 | if (++o == l) |
143 | goto err; |
144 | |
145 | i2 = (d->type == V_ASN1_UTCTIME) ? i + 1 : i; |
146 | |
147 | if ((n < min[i2]) || (n > max[i2])) |
148 | goto err; |
149 | switch (i2) { |
150 | case 0: |
151 | /* UTC will never be here */ |
152 | tmp.tm_year = n * 100 - 1900; |
153 | break; |
154 | case 1: |
155 | if (d->type == V_ASN1_UTCTIME) |
156 | tmp.tm_year = n < 50 ? n + 100 : n; |
157 | else |
158 | tmp.tm_year += n; |
159 | break; |
160 | case 2: |
161 | tmp.tm_mon = n - 1; |
162 | break; |
163 | case 3: |
164 | /* check if tm_mday is valid in tm_mon */ |
165 | if (tmp.tm_mon == 1) { |
166 | /* it's February */ |
167 | md = mdays[1] + leap_year(tmp.tm_year + 1900); |
168 | } else { |
169 | md = mdays[tmp.tm_mon]; |
170 | } |
171 | if (n > md) |
172 | goto err; |
173 | tmp.tm_mday = n; |
174 | determine_days(&tmp); |
175 | break; |
176 | case 4: |
177 | tmp.tm_hour = n; |
178 | break; |
179 | case 5: |
180 | tmp.tm_min = n; |
181 | break; |
182 | case 6: |
183 | tmp.tm_sec = n; |
184 | break; |
185 | } |
186 | } |
187 | |
188 | /* |
189 | * Optional fractional seconds: decimal point followed by one or more |
190 | * digits. |
191 | */ |
192 | if (d->type == V_ASN1_GENERALIZEDTIME && a[o] == period) { |
193 | if (strict) |
194 | /* RFC 5280 forbids fractional seconds */ |
195 | goto err; |
196 | if (++o == l) |
197 | goto err; |
198 | i = o; |
199 | while ((o < l) && ascii_isdigit(a[o])) |
200 | o++; |
201 | /* Must have at least one digit after decimal point */ |
202 | if (i == o) |
203 | goto err; |
204 | /* no more bytes to read, but we haven't seen time-zone yet */ |
205 | if (o == l) |
206 | goto err; |
207 | } |
208 | |
209 | /* |
210 | * 'o' will never point to '\0' at this point, the only chance |
211 | * 'o' can point to '\0' is either the subsequent if or the first |
212 | * else if is true. |
213 | */ |
214 | if (a[o] == upper_z) { |
215 | o++; |
216 | } else if (!strict && ((a[o] == plus) || (a[o] == minus))) { |
217 | int offsign = a[o] == minus ? 1 : -1; |
218 | int offset = 0; |
219 | |
220 | o++; |
221 | /* |
222 | * if not equal, no need to do subsequent checks |
223 | * since the following for-loop will add 'o' by 4 |
224 | * and the final return statement will check if 'l' |
225 | * and 'o' are equal. |
226 | */ |
227 | if (o + 4 != l) |
228 | goto err; |
229 | for (i = end; i < end + 2; i++) { |
230 | if (!ascii_isdigit(a[o])) |
231 | goto err; |
232 | n = a[o] - num_zero; |
233 | o++; |
234 | if (!ascii_isdigit(a[o])) |
235 | goto err; |
236 | n = (n * 10) + a[o] - num_zero; |
237 | i2 = (d->type == V_ASN1_UTCTIME) ? i + 1 : i; |
238 | if ((n < min[i2]) || (n > max[i2])) |
239 | goto err; |
240 | /* if tm is NULL, no need to adjust */ |
241 | if (tm != NULL) { |
242 | if (i == end) |
243 | offset = n * 3600; |
244 | else if (i == end + 1) |
245 | offset += n * 60; |
246 | } |
247 | o++; |
248 | } |
249 | if (offset && !OPENSSL_gmtime_adj(&tmp, 0, offset * offsign)) |
250 | goto err; |
251 | } else { |
252 | /* not Z, or not +/- in non-strict mode */ |
253 | goto err; |
254 | } |
255 | if (o == l) { |
256 | /* success, check if tm should be filled */ |
257 | if (tm != NULL) |
258 | *tm = tmp; |
259 | return 1; |
260 | } |
261 | err: |
262 | return 0; |
263 | } |
264 | |
265 | ASN1_TIME *asn1_time_from_tm(ASN1_TIME *s, struct tm *ts, int type) |
266 | { |
267 | char* p; |
268 | ASN1_TIME *tmps = NULL; |
269 | const size_t len = 20; |
270 | |
271 | if (type == V_ASN1_UNDEF) { |
272 | if (is_utc(ts->tm_year)) |
273 | type = V_ASN1_UTCTIME; |
274 | else |
275 | type = V_ASN1_GENERALIZEDTIME; |
276 | } else if (type == V_ASN1_UTCTIME) { |
277 | if (!is_utc(ts->tm_year)) |
278 | goto err; |
279 | } else if (type != V_ASN1_GENERALIZEDTIME) { |
280 | goto err; |
281 | } |
282 | |
283 | if (s == NULL) |
284 | tmps = ASN1_STRING_new(); |
285 | else |
286 | tmps = s; |
287 | if (tmps == NULL) |
288 | return NULL; |
289 | |
290 | if (!ASN1_STRING_set(tmps, NULL, len)) |
291 | goto err; |
292 | |
293 | tmps->type = type; |
294 | p = (char*)tmps->data; |
295 | |
296 | if (type == V_ASN1_GENERALIZEDTIME) |
297 | tmps->length = BIO_snprintf(p, len, "%04d%02d%02d%02d%02d%02dZ" , |
298 | ts->tm_year + 1900, ts->tm_mon + 1, |
299 | ts->tm_mday, ts->tm_hour, ts->tm_min, |
300 | ts->tm_sec); |
301 | else |
302 | tmps->length = BIO_snprintf(p, len, "%02d%02d%02d%02d%02d%02dZ" , |
303 | ts->tm_year % 100, ts->tm_mon + 1, |
304 | ts->tm_mday, ts->tm_hour, ts->tm_min, |
305 | ts->tm_sec); |
306 | |
307 | #ifdef CHARSET_EBCDIC |
308 | ebcdic2ascii(tmps->data, tmps->data, tmps->length); |
309 | #endif |
310 | return tmps; |
311 | err: |
312 | if (tmps != s) |
313 | ASN1_STRING_free(tmps); |
314 | return NULL; |
315 | } |
316 | |
317 | ASN1_TIME *ASN1_TIME_set(ASN1_TIME *s, time_t t) |
318 | { |
319 | return ASN1_TIME_adj(s, t, 0, 0); |
320 | } |
321 | |
322 | ASN1_TIME *ASN1_TIME_adj(ASN1_TIME *s, time_t t, |
323 | int offset_day, long offset_sec) |
324 | { |
325 | struct tm *ts; |
326 | struct tm data; |
327 | |
328 | ts = OPENSSL_gmtime(&t, &data); |
329 | if (ts == NULL) { |
330 | ASN1err(ASN1_F_ASN1_TIME_ADJ, ASN1_R_ERROR_GETTING_TIME); |
331 | return NULL; |
332 | } |
333 | if (offset_day || offset_sec) { |
334 | if (!OPENSSL_gmtime_adj(ts, offset_day, offset_sec)) |
335 | return NULL; |
336 | } |
337 | return asn1_time_from_tm(s, ts, V_ASN1_UNDEF); |
338 | } |
339 | |
340 | int ASN1_TIME_check(const ASN1_TIME *t) |
341 | { |
342 | if (t->type == V_ASN1_GENERALIZEDTIME) |
343 | return ASN1_GENERALIZEDTIME_check(t); |
344 | else if (t->type == V_ASN1_UTCTIME) |
345 | return ASN1_UTCTIME_check(t); |
346 | return 0; |
347 | } |
348 | |
349 | /* Convert an ASN1_TIME structure to GeneralizedTime */ |
350 | ASN1_GENERALIZEDTIME *ASN1_TIME_to_generalizedtime(const ASN1_TIME *t, |
351 | ASN1_GENERALIZEDTIME **out) |
352 | { |
353 | ASN1_GENERALIZEDTIME *ret = NULL; |
354 | struct tm tm; |
355 | |
356 | if (!ASN1_TIME_to_tm(t, &tm)) |
357 | return NULL; |
358 | |
359 | if (out != NULL) |
360 | ret = *out; |
361 | |
362 | ret = asn1_time_from_tm(ret, &tm, V_ASN1_GENERALIZEDTIME); |
363 | |
364 | if (out != NULL && ret != NULL) |
365 | *out = ret; |
366 | |
367 | return ret; |
368 | } |
369 | |
370 | int ASN1_TIME_set_string(ASN1_TIME *s, const char *str) |
371 | { |
372 | /* Try UTC, if that fails, try GENERALIZED */ |
373 | if (ASN1_UTCTIME_set_string(s, str)) |
374 | return 1; |
375 | return ASN1_GENERALIZEDTIME_set_string(s, str); |
376 | } |
377 | |
378 | int ASN1_TIME_set_string_X509(ASN1_TIME *s, const char *str) |
379 | { |
380 | ASN1_TIME t; |
381 | struct tm tm; |
382 | int rv = 0; |
383 | |
384 | t.length = strlen(str); |
385 | t.data = (unsigned char *)str; |
386 | t.flags = ASN1_STRING_FLAG_X509_TIME; |
387 | |
388 | t.type = V_ASN1_UTCTIME; |
389 | |
390 | if (!ASN1_TIME_check(&t)) { |
391 | t.type = V_ASN1_GENERALIZEDTIME; |
392 | if (!ASN1_TIME_check(&t)) |
393 | goto out; |
394 | } |
395 | |
396 | /* |
397 | * Per RFC 5280 (section 4.1.2.5.), the valid input time |
398 | * strings should be encoded with the following rules: |
399 | * |
400 | * 1. UTC: YYMMDDHHMMSSZ, if YY < 50 (20YY) --> UTC: YYMMDDHHMMSSZ |
401 | * 2. UTC: YYMMDDHHMMSSZ, if YY >= 50 (19YY) --> UTC: YYMMDDHHMMSSZ |
402 | * 3. G'd: YYYYMMDDHHMMSSZ, if YYYY >= 2050 --> G'd: YYYYMMDDHHMMSSZ |
403 | * 4. G'd: YYYYMMDDHHMMSSZ, if YYYY < 2050 --> UTC: YYMMDDHHMMSSZ |
404 | * |
405 | * Only strings of the 4th rule should be reformatted, but since a |
406 | * UTC can only present [1950, 2050), so if the given time string |
407 | * is less than 1950 (e.g. 19230419000000Z), we do nothing... |
408 | */ |
409 | |
410 | if (s != NULL && t.type == V_ASN1_GENERALIZEDTIME) { |
411 | if (!asn1_time_to_tm(&tm, &t)) |
412 | goto out; |
413 | if (is_utc(tm.tm_year)) { |
414 | t.length -= 2; |
415 | /* |
416 | * it's OK to let original t.data go since that's assigned |
417 | * to a piece of memory allocated outside of this function. |
418 | * new t.data would be freed after ASN1_STRING_copy is done. |
419 | */ |
420 | t.data = OPENSSL_zalloc(t.length + 1); |
421 | if (t.data == NULL) |
422 | goto out; |
423 | memcpy(t.data, str + 2, t.length); |
424 | t.type = V_ASN1_UTCTIME; |
425 | } |
426 | } |
427 | |
428 | if (s == NULL || ASN1_STRING_copy((ASN1_STRING *)s, (ASN1_STRING *)&t)) |
429 | rv = 1; |
430 | |
431 | if (t.data != (unsigned char *)str) |
432 | OPENSSL_free(t.data); |
433 | out: |
434 | return rv; |
435 | } |
436 | |
437 | int ASN1_TIME_to_tm(const ASN1_TIME *s, struct tm *tm) |
438 | { |
439 | if (s == NULL) { |
440 | time_t now_t; |
441 | |
442 | time(&now_t); |
443 | memset(tm, 0, sizeof(*tm)); |
444 | if (OPENSSL_gmtime(&now_t, tm) != NULL) |
445 | return 1; |
446 | return 0; |
447 | } |
448 | |
449 | return asn1_time_to_tm(tm, s); |
450 | } |
451 | |
452 | int ASN1_TIME_diff(int *pday, int *psec, |
453 | const ASN1_TIME *from, const ASN1_TIME *to) |
454 | { |
455 | struct tm tm_from, tm_to; |
456 | |
457 | if (!ASN1_TIME_to_tm(from, &tm_from)) |
458 | return 0; |
459 | if (!ASN1_TIME_to_tm(to, &tm_to)) |
460 | return 0; |
461 | return OPENSSL_gmtime_diff(pday, psec, &tm_from, &tm_to); |
462 | } |
463 | |
464 | static const char _asn1_mon[12][4] = { |
465 | "Jan" , "Feb" , "Mar" , "Apr" , "May" , "Jun" , |
466 | "Jul" , "Aug" , "Sep" , "Oct" , "Nov" , "Dec" |
467 | }; |
468 | |
469 | int ASN1_TIME_print(BIO *bp, const ASN1_TIME *tm) |
470 | { |
471 | char *v; |
472 | int gmt = 0, l; |
473 | struct tm stm; |
474 | const char upper_z = 0x5A, period = 0x2E; |
475 | |
476 | if (!asn1_time_to_tm(&stm, tm)) { |
477 | /* asn1_time_to_tm will check the time type */ |
478 | goto err; |
479 | } |
480 | |
481 | l = tm->length; |
482 | v = (char *)tm->data; |
483 | if (v[l - 1] == upper_z) |
484 | gmt = 1; |
485 | |
486 | if (tm->type == V_ASN1_GENERALIZEDTIME) { |
487 | char *f = NULL; |
488 | int f_len = 0; |
489 | |
490 | /* |
491 | * Try to parse fractional seconds. '14' is the place of |
492 | * 'fraction point' in a GeneralizedTime string. |
493 | */ |
494 | if (tm->length > 15 && v[14] == period) { |
495 | f = &v[14]; |
496 | f_len = 1; |
497 | while (14 + f_len < l && ascii_isdigit(f[f_len])) |
498 | ++f_len; |
499 | } |
500 | |
501 | return BIO_printf(bp, "%s %2d %02d:%02d:%02d%.*s %d%s" , |
502 | _asn1_mon[stm.tm_mon], stm.tm_mday, stm.tm_hour, |
503 | stm.tm_min, stm.tm_sec, f_len, f, stm.tm_year + 1900, |
504 | (gmt ? " GMT" : "" )) > 0; |
505 | } else { |
506 | return BIO_printf(bp, "%s %2d %02d:%02d:%02d %d%s" , |
507 | _asn1_mon[stm.tm_mon], stm.tm_mday, stm.tm_hour, |
508 | stm.tm_min, stm.tm_sec, stm.tm_year + 1900, |
509 | (gmt ? " GMT" : "" )) > 0; |
510 | } |
511 | err: |
512 | BIO_write(bp, "Bad time value" , 14); |
513 | return 0; |
514 | } |
515 | |
516 | int ASN1_TIME_cmp_time_t(const ASN1_TIME *s, time_t t) |
517 | { |
518 | struct tm stm, ttm; |
519 | int day, sec; |
520 | |
521 | if (!ASN1_TIME_to_tm(s, &stm)) |
522 | return -2; |
523 | |
524 | if (!OPENSSL_gmtime(&t, &ttm)) |
525 | return -2; |
526 | |
527 | if (!OPENSSL_gmtime_diff(&day, &sec, &ttm, &stm)) |
528 | return -2; |
529 | |
530 | if (day > 0 || sec > 0) |
531 | return 1; |
532 | if (day < 0 || sec < 0) |
533 | return -1; |
534 | return 0; |
535 | } |
536 | |
537 | int ASN1_TIME_normalize(ASN1_TIME *t) |
538 | { |
539 | struct tm tm; |
540 | |
541 | if (!ASN1_TIME_to_tm(t, &tm)) |
542 | return 0; |
543 | |
544 | return asn1_time_from_tm(t, &tm, V_ASN1_UNDEF) != NULL; |
545 | } |
546 | |
547 | int ASN1_TIME_compare(const ASN1_TIME *a, const ASN1_TIME *b) |
548 | { |
549 | int day, sec; |
550 | |
551 | if (!ASN1_TIME_diff(&day, &sec, b, a)) |
552 | return -2; |
553 | if (day > 0 || sec > 0) |
554 | return 1; |
555 | if (day < 0 || sec < 0) |
556 | return -1; |
557 | return 0; |
558 | } |
559 | |