1 /*
2 * Copyright 1999-2021 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/asn1.h"
20 #include "crypto/ctype.h"
21 #include "internal/cryptlib.h"
22 #include <openssl/asn1t.h>
23 #include "asn1_local.h"
24
IMPLEMENT_ASN1_MSTRING(ASN1_TIME,B_ASN1_TIME)25 IMPLEMENT_ASN1_MSTRING(ASN1_TIME, B_ASN1_TIME)
26
27 IMPLEMENT_ASN1_FUNCTIONS(ASN1_TIME)
28 IMPLEMENT_ASN1_DUP_FUNCTION(ASN1_TIME)
29
30 static int is_utc(const int year)
31 {
32 if (50 <= year && year <= 149)
33 return 1;
34 return 0;
35 }
36
leap_year(const int year)37 static int leap_year(const int year)
38 {
39 if (year % 400 == 0 || (year % 100 != 0 && year % 4 == 0))
40 return 1;
41 return 0;
42 }
43
44 /*
45 * Compute the day of the week and the day of the year from the year, month
46 * and day. The day of the year is straightforward, the day of the week uses
47 * a form of Zeller's congruence. For this months start with March and are
48 * numbered 4 through 15.
49 */
determine_days(struct tm * tm)50 static void determine_days(struct tm *tm)
51 {
52 static const int ydays[12] = {
53 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334
54 };
55 int y = tm->tm_year + 1900;
56 int m = tm->tm_mon;
57 int d = tm->tm_mday;
58 int c;
59
60 tm->tm_yday = ydays[m] + d - 1;
61 if (m >= 2) {
62 /* March and onwards can be one day further into the year */
63 tm->tm_yday += leap_year(y);
64 m += 2;
65 } else {
66 /* Treat January and February as part of the previous year */
67 m += 14;
68 y--;
69 }
70 c = y / 100;
71 y %= 100;
72 /* Zeller's congruence */
73 tm->tm_wday = (d + (13 * m) / 5 + y + y / 4 + c / 4 + 5 * c + 6) % 7;
74 }
75
ossl_asn1_time_to_tm(struct tm * tm,const ASN1_TIME * d)76 int ossl_asn1_time_to_tm(struct tm *tm, const ASN1_TIME *d)
77 {
78 static const int min[9] = { 0, 0, 1, 1, 0, 0, 0, 0, 0 };
79 static const int max[9] = { 99, 99, 12, 31, 23, 59, 59, 12, 59 };
80 static const int mdays[12] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
81 char *a;
82 int n, i, i2, l, o, min_l = 11, strict = 0, end = 6, btz = 5, md;
83 struct tm tmp;
84 #if defined(CHARSET_EBCDIC)
85 const char upper_z = 0x5A, num_zero = 0x30, period = 0x2E, minus = 0x2D, plus = 0x2B;
86 #else
87 const char upper_z = 'Z', num_zero = '0', period = '.', minus = '-', plus = '+';
88 #endif
89 /*
90 * ASN1_STRING_FLAG_X509_TIME is used to enforce RFC 5280
91 * time string format, in which:
92 *
93 * 1. "seconds" is a 'MUST'
94 * 2. "Zulu" timezone is a 'MUST'
95 * 3. "+|-" is not allowed to indicate a time zone
96 */
97 if (d->type == V_ASN1_UTCTIME) {
98 if (d->flags & ASN1_STRING_FLAG_X509_TIME) {
99 min_l = 13;
100 strict = 1;
101 }
102 } else if (d->type == V_ASN1_GENERALIZEDTIME) {
103 end = 7;
104 btz = 6;
105 if (d->flags & ASN1_STRING_FLAG_X509_TIME) {
106 min_l = 15;
107 strict = 1;
108 } else {
109 min_l = 13;
110 }
111 } else {
112 return 0;
113 }
114
115 l = d->length;
116 a = (char *)d->data;
117 o = 0;
118 memset(&tmp, 0, sizeof(tmp));
119
120 /*
121 * GENERALIZEDTIME is similar to UTCTIME except the year is represented
122 * as YYYY. This stuff treats everything as a two digit field so make
123 * first two fields 00 to 99
124 */
125
126 if (l < min_l)
127 goto err;
128 for (i = 0; i < end; i++) {
129 if (!strict && (i == btz) && ((a[o] == upper_z) || (a[o] == plus) || (a[o] == minus))) {
130 i++;
131 break;
132 }
133 if (!ossl_ascii_isdigit(a[o]))
134 goto err;
135 n = a[o] - num_zero;
136 /* incomplete 2-digital number */
137 if (++o == l)
138 goto err;
139
140 if (!ossl_ascii_isdigit(a[o]))
141 goto err;
142 n = (n * 10) + a[o] - num_zero;
143 /* no more bytes to read, but we haven't seen time-zone yet */
144 if (++o == l)
145 goto err;
146
147 i2 = (d->type == V_ASN1_UTCTIME) ? i + 1 : i;
148
149 if ((n < min[i2]) || (n > max[i2]))
150 goto err;
151 switch (i2) {
152 case 0:
153 /* UTC will never be here */
154 tmp.tm_year = n * 100 - 1900;
155 break;
156 case 1:
157 if (d->type == V_ASN1_UTCTIME)
158 tmp.tm_year = n < 50 ? n + 100 : n;
159 else
160 tmp.tm_year += n;
161 break;
162 case 2:
163 tmp.tm_mon = n - 1;
164 break;
165 case 3:
166 /* check if tm_mday is valid in tm_mon */
167 if (tmp.tm_mon == 1) {
168 /* it's February */
169 md = mdays[1] + leap_year(tmp.tm_year + 1900);
170 } else {
171 md = mdays[tmp.tm_mon];
172 }
173 if (n > md)
174 goto err;
175 tmp.tm_mday = n;
176 determine_days(&tmp);
177 break;
178 case 4:
179 tmp.tm_hour = n;
180 break;
181 case 5:
182 tmp.tm_min = n;
183 break;
184 case 6:
185 tmp.tm_sec = n;
186 break;
187 }
188 }
189
190 /*
191 * Optional fractional seconds: decimal point followed by one or more
192 * digits.
193 */
194 if (d->type == V_ASN1_GENERALIZEDTIME && a[o] == period) {
195 if (strict)
196 /* RFC 5280 forbids fractional seconds */
197 goto err;
198 if (++o == l)
199 goto err;
200 i = o;
201 while ((o < l) && ossl_ascii_isdigit(a[o]))
202 o++;
203 /* Must have at least one digit after decimal point */
204 if (i == o)
205 goto err;
206 /* no more bytes to read, but we haven't seen time-zone yet */
207 if (o == l)
208 goto err;
209 }
210
211 /*
212 * 'o' will never point to '\0' at this point, the only chance
213 * 'o' can point to '\0' is either the subsequent if or the first
214 * else if is true.
215 */
216 if (a[o] == upper_z) {
217 o++;
218 } else if (!strict && ((a[o] == plus) || (a[o] == minus))) {
219 int offsign = a[o] == minus ? 1 : -1;
220 int offset = 0;
221
222 o++;
223 /*
224 * if not equal, no need to do subsequent checks
225 * since the following for-loop will add 'o' by 4
226 * and the final return statement will check if 'l'
227 * and 'o' are equal.
228 */
229 if (o + 4 != l)
230 goto err;
231 for (i = end; i < end + 2; i++) {
232 if (!ossl_ascii_isdigit(a[o]))
233 goto err;
234 n = a[o] - num_zero;
235 o++;
236 if (!ossl_ascii_isdigit(a[o]))
237 goto err;
238 n = (n * 10) + a[o] - num_zero;
239 i2 = (d->type == V_ASN1_UTCTIME) ? i + 1 : i;
240 if ((n < min[i2]) || (n > max[i2]))
241 goto err;
242 /* if tm is NULL, no need to adjust */
243 if (tm != NULL) {
244 if (i == end)
245 offset = n * 3600;
246 else if (i == end + 1)
247 offset += n * 60;
248 }
249 o++;
250 }
251 if (offset && !OPENSSL_gmtime_adj(&tmp, 0, offset * offsign))
252 goto err;
253 } else {
254 /* not Z, or not +/- in non-strict mode */
255 goto err;
256 }
257 if (o == l) {
258 /* success, check if tm should be filled */
259 if (tm != NULL)
260 *tm = tmp;
261 return 1;
262 }
263 err:
264 return 0;
265 }
266
ossl_asn1_time_from_tm(ASN1_TIME * s,struct tm * ts,int type)267 ASN1_TIME *ossl_asn1_time_from_tm(ASN1_TIME *s, struct tm *ts, int type)
268 {
269 char* p;
270 ASN1_TIME *tmps = NULL;
271 const size_t len = 20;
272
273 if (type == V_ASN1_UNDEF) {
274 if (is_utc(ts->tm_year))
275 type = V_ASN1_UTCTIME;
276 else
277 type = V_ASN1_GENERALIZEDTIME;
278 } else if (type == V_ASN1_UTCTIME) {
279 if (!is_utc(ts->tm_year))
280 goto err;
281 } else if (type != V_ASN1_GENERALIZEDTIME) {
282 goto err;
283 }
284
285 if (s == NULL)
286 tmps = ASN1_STRING_new();
287 else
288 tmps = s;
289 if (tmps == NULL)
290 return NULL;
291
292 if (!ASN1_STRING_set(tmps, NULL, len))
293 goto err;
294
295 tmps->type = type;
296 p = (char*)tmps->data;
297
298 if (type == V_ASN1_GENERALIZEDTIME)
299 tmps->length = BIO_snprintf(p, len, "%04d%02d%02d%02d%02d%02dZ",
300 ts->tm_year + 1900, ts->tm_mon + 1,
301 ts->tm_mday, ts->tm_hour, ts->tm_min,
302 ts->tm_sec);
303 else
304 tmps->length = BIO_snprintf(p, len, "%02d%02d%02d%02d%02d%02dZ",
305 ts->tm_year % 100, ts->tm_mon + 1,
306 ts->tm_mday, ts->tm_hour, ts->tm_min,
307 ts->tm_sec);
308
309 #ifdef CHARSET_EBCDIC
310 ebcdic2ascii(tmps->data, tmps->data, tmps->length);
311 #endif
312 return tmps;
313 err:
314 if (tmps != s)
315 ASN1_STRING_free(tmps);
316 return NULL;
317 }
318
ASN1_TIME_set(ASN1_TIME * s,time_t t)319 ASN1_TIME *ASN1_TIME_set(ASN1_TIME *s, time_t t)
320 {
321 return ASN1_TIME_adj(s, t, 0, 0);
322 }
323
ASN1_TIME_adj(ASN1_TIME * s,time_t t,int offset_day,long offset_sec)324 ASN1_TIME *ASN1_TIME_adj(ASN1_TIME *s, time_t t,
325 int offset_day, long offset_sec)
326 {
327 struct tm *ts;
328 struct tm data;
329
330 ts = OPENSSL_gmtime(&t, &data);
331 if (ts == NULL) {
332 ERR_raise(ERR_LIB_ASN1, ASN1_R_ERROR_GETTING_TIME);
333 return NULL;
334 }
335 if (offset_day || offset_sec) {
336 if (!OPENSSL_gmtime_adj(ts, offset_day, offset_sec))
337 return NULL;
338 }
339 return ossl_asn1_time_from_tm(s, ts, V_ASN1_UNDEF);
340 }
341
ASN1_TIME_check(const ASN1_TIME * t)342 int ASN1_TIME_check(const ASN1_TIME *t)
343 {
344 if (t->type == V_ASN1_GENERALIZEDTIME)
345 return ASN1_GENERALIZEDTIME_check(t);
346 else if (t->type == V_ASN1_UTCTIME)
347 return ASN1_UTCTIME_check(t);
348 return 0;
349 }
350
351 /* Convert an ASN1_TIME structure to GeneralizedTime */
ASN1_TIME_to_generalizedtime(const ASN1_TIME * t,ASN1_GENERALIZEDTIME ** out)352 ASN1_GENERALIZEDTIME *ASN1_TIME_to_generalizedtime(const ASN1_TIME *t,
353 ASN1_GENERALIZEDTIME **out)
354 {
355 ASN1_GENERALIZEDTIME *ret = NULL;
356 struct tm tm;
357
358 if (!ASN1_TIME_to_tm(t, &tm))
359 return NULL;
360
361 if (out != NULL)
362 ret = *out;
363
364 ret = ossl_asn1_time_from_tm(ret, &tm, V_ASN1_GENERALIZEDTIME);
365
366 if (out != NULL && ret != NULL)
367 *out = ret;
368
369 return ret;
370 }
371
ASN1_TIME_set_string(ASN1_TIME * s,const char * str)372 int ASN1_TIME_set_string(ASN1_TIME *s, const char *str)
373 {
374 /* Try UTC, if that fails, try GENERALIZED */
375 if (ASN1_UTCTIME_set_string(s, str))
376 return 1;
377 return ASN1_GENERALIZEDTIME_set_string(s, str);
378 }
379
ASN1_TIME_set_string_X509(ASN1_TIME * s,const char * str)380 int ASN1_TIME_set_string_X509(ASN1_TIME *s, const char *str)
381 {
382 ASN1_TIME t;
383 struct tm tm;
384 int rv = 0;
385
386 t.length = strlen(str);
387 t.data = (unsigned char *)str;
388 t.flags = ASN1_STRING_FLAG_X509_TIME;
389
390 t.type = V_ASN1_UTCTIME;
391
392 if (!ASN1_TIME_check(&t)) {
393 t.type = V_ASN1_GENERALIZEDTIME;
394 if (!ASN1_TIME_check(&t))
395 goto out;
396 }
397
398 /*
399 * Per RFC 5280 (section 4.1.2.5.), the valid input time
400 * strings should be encoded with the following rules:
401 *
402 * 1. UTC: YYMMDDHHMMSSZ, if YY < 50 (20YY) --> UTC: YYMMDDHHMMSSZ
403 * 2. UTC: YYMMDDHHMMSSZ, if YY >= 50 (19YY) --> UTC: YYMMDDHHMMSSZ
404 * 3. G'd: YYYYMMDDHHMMSSZ, if YYYY >= 2050 --> G'd: YYYYMMDDHHMMSSZ
405 * 4. G'd: YYYYMMDDHHMMSSZ, if YYYY < 2050 --> UTC: YYMMDDHHMMSSZ
406 *
407 * Only strings of the 4th rule should be reformatted, but since a
408 * UTC can only present [1950, 2050), so if the given time string
409 * is less than 1950 (e.g. 19230419000000Z), we do nothing...
410 */
411
412 if (s != NULL && t.type == V_ASN1_GENERALIZEDTIME) {
413 if (!ossl_asn1_time_to_tm(&tm, &t))
414 goto out;
415 if (is_utc(tm.tm_year)) {
416 t.length -= 2;
417 /*
418 * it's OK to let original t.data go since that's assigned
419 * to a piece of memory allocated outside of this function.
420 * new t.data would be freed after ASN1_STRING_copy is done.
421 */
422 t.data = OPENSSL_zalloc(t.length + 1);
423 if (t.data == NULL) {
424 ERR_raise(ERR_LIB_ASN1, ERR_R_MALLOC_FAILURE);
425 goto out;
426 }
427 memcpy(t.data, str + 2, t.length);
428 t.type = V_ASN1_UTCTIME;
429 }
430 }
431
432 if (s == NULL || ASN1_STRING_copy((ASN1_STRING *)s, (ASN1_STRING *)&t))
433 rv = 1;
434
435 if (t.data != (unsigned char *)str)
436 OPENSSL_free(t.data);
437 out:
438 return rv;
439 }
440
ASN1_TIME_to_tm(const ASN1_TIME * s,struct tm * tm)441 int ASN1_TIME_to_tm(const ASN1_TIME *s, struct tm *tm)
442 {
443 if (s == NULL) {
444 time_t now_t;
445
446 time(&now_t);
447 memset(tm, 0, sizeof(*tm));
448 if (OPENSSL_gmtime(&now_t, tm) != NULL)
449 return 1;
450 return 0;
451 }
452
453 return ossl_asn1_time_to_tm(tm, s);
454 }
455
ASN1_TIME_diff(int * pday,int * psec,const ASN1_TIME * from,const ASN1_TIME * to)456 int ASN1_TIME_diff(int *pday, int *psec,
457 const ASN1_TIME *from, const ASN1_TIME *to)
458 {
459 struct tm tm_from, tm_to;
460
461 if (!ASN1_TIME_to_tm(from, &tm_from))
462 return 0;
463 if (!ASN1_TIME_to_tm(to, &tm_to))
464 return 0;
465 return OPENSSL_gmtime_diff(pday, psec, &tm_from, &tm_to);
466 }
467
468 static const char _asn1_mon[12][4] = {
469 "Jan", "Feb", "Mar", "Apr", "May", "Jun",
470 "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
471 };
472
473 /* prints the time with the default date format (RFC 822) */
ASN1_TIME_print(BIO * bp,const ASN1_TIME * tm)474 int ASN1_TIME_print(BIO *bp, const ASN1_TIME *tm)
475 {
476 return ASN1_TIME_print_ex(bp, tm, ASN1_DTFLGS_RFC822);
477 }
478
479 /* returns 1 on success, 0 on BIO write error or parse failure */
ASN1_TIME_print_ex(BIO * bp,const ASN1_TIME * tm,unsigned long flags)480 int ASN1_TIME_print_ex(BIO *bp, const ASN1_TIME *tm, unsigned long flags)
481 {
482 return ossl_asn1_time_print_ex(bp, tm, flags) > 0;
483 }
484
485
486 /* prints the time with the date format of ISO 8601 */
487 /* returns 0 on BIO write error, else -1 in case of parse failure, else 1 */
ossl_asn1_time_print_ex(BIO * bp,const ASN1_TIME * tm,unsigned long flags)488 int ossl_asn1_time_print_ex(BIO *bp, const ASN1_TIME *tm, unsigned long flags)
489 {
490 char *v;
491 int gmt = 0, l;
492 struct tm stm;
493 const char upper_z = 0x5A, period = 0x2E;
494
495 /* ossl_asn1_time_to_tm will check the time type */
496 if (!ossl_asn1_time_to_tm(&stm, tm))
497 return BIO_write(bp, "Bad time value", 14) ? -1 : 0;
498
499 l = tm->length;
500 v = (char *)tm->data;
501 if (v[l - 1] == upper_z)
502 gmt = 1;
503
504 if (tm->type == V_ASN1_GENERALIZEDTIME) {
505 char *f = NULL;
506 int f_len = 0;
507
508 /*
509 * Try to parse fractional seconds. '14' is the place of
510 * 'fraction point' in a GeneralizedTime string.
511 */
512 if (tm->length > 15 && v[14] == period) {
513 f = &v[14];
514 f_len = 1;
515 while (14 + f_len < l && ossl_ascii_isdigit(f[f_len]))
516 ++f_len;
517 }
518
519 if ((flags & ASN1_DTFLGS_TYPE_MASK) == ASN1_DTFLGS_ISO8601) {
520 return BIO_printf(bp, "%4d-%02d-%02d %02d:%02d:%02d%.*s%s",
521 stm.tm_year + 1900, stm.tm_mon + 1,
522 stm.tm_mday, stm.tm_hour,
523 stm.tm_min, stm.tm_sec, f_len, f,
524 (gmt ? "Z" : "")) > 0;
525 }
526 else {
527 return BIO_printf(bp, "%s %2d %02d:%02d:%02d%.*s %d%s",
528 _asn1_mon[stm.tm_mon], stm.tm_mday, stm.tm_hour,
529 stm.tm_min, stm.tm_sec, f_len, f, stm.tm_year + 1900,
530 (gmt ? " GMT" : "")) > 0;
531 }
532 } else {
533 if ((flags & ASN1_DTFLGS_TYPE_MASK) == ASN1_DTFLGS_ISO8601) {
534 return BIO_printf(bp, "%4d-%02d-%02d %02d:%02d:%02d%s",
535 stm.tm_year + 1900, stm.tm_mon + 1,
536 stm.tm_mday, stm.tm_hour,
537 stm.tm_min, stm.tm_sec,
538 (gmt ? "Z" : "")) > 0;
539 }
540 else {
541 return BIO_printf(bp, "%s %2d %02d:%02d:%02d %d%s",
542 _asn1_mon[stm.tm_mon], stm.tm_mday, stm.tm_hour,
543 stm.tm_min, stm.tm_sec, stm.tm_year + 1900,
544 (gmt ? " GMT" : "")) > 0;
545 }
546 }
547 }
548
ASN1_TIME_cmp_time_t(const ASN1_TIME * s,time_t t)549 int ASN1_TIME_cmp_time_t(const ASN1_TIME *s, time_t t)
550 {
551 struct tm stm, ttm;
552 int day, sec;
553
554 if (!ASN1_TIME_to_tm(s, &stm))
555 return -2;
556
557 if (!OPENSSL_gmtime(&t, &ttm))
558 return -2;
559
560 if (!OPENSSL_gmtime_diff(&day, &sec, &ttm, &stm))
561 return -2;
562
563 if (day > 0 || sec > 0)
564 return 1;
565 if (day < 0 || sec < 0)
566 return -1;
567 return 0;
568 }
569
ASN1_TIME_normalize(ASN1_TIME * t)570 int ASN1_TIME_normalize(ASN1_TIME *t)
571 {
572 struct tm tm;
573
574 if (!ASN1_TIME_to_tm(t, &tm))
575 return 0;
576
577 return ossl_asn1_time_from_tm(t, &tm, V_ASN1_UNDEF) != NULL;
578 }
579
ASN1_TIME_compare(const ASN1_TIME * a,const ASN1_TIME * b)580 int ASN1_TIME_compare(const ASN1_TIME *a, const ASN1_TIME *b)
581 {
582 int day, sec;
583
584 if (!ASN1_TIME_diff(&day, &sec, b, a))
585 return -2;
586 if (day > 0 || sec > 0)
587 return 1;
588 if (day < 0 || sec < 0)
589 return -1;
590 return 0;
591 }
592