1 /*
2 * Copyright 1999-2024 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, 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 timezone
96 */
97 if (d->type == V_ASN1_UTCTIME) {
98 min_l = 13;
99 if (d->flags & ASN1_STRING_FLAG_X509_TIME) {
100 strict = 1;
101 }
102 } else if (d->type == V_ASN1_GENERALIZEDTIME) {
103 end = 7;
104 btz = 6;
105 min_l = 15;
106 if (d->flags & ASN1_STRING_FLAG_X509_TIME) {
107 strict = 1;
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 (!ossl_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 (!ossl_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) && ossl_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 (!ossl_ascii_isdigit(a[o]))
231 goto err;
232 n = a[o] - num_zero;
233 o++;
234 if (!ossl_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
ossl_asn1_time_from_tm(ASN1_TIME * s,struct tm * ts,int type)265 ASN1_TIME *ossl_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 (ts->tm_mon > INT_MAX - 1)
297 goto err;
298
299 if (type == V_ASN1_GENERALIZEDTIME) {
300 if (ts->tm_year > INT_MAX - 1900)
301 goto err;
302 tmps->length = BIO_snprintf(p, len, "%04d%02d%02d%02d%02d%02dZ",
303 ts->tm_year + 1900, ts->tm_mon + 1,
304 ts->tm_mday, ts->tm_hour, ts->tm_min,
305 ts->tm_sec);
306 } else {
307 tmps->length = BIO_snprintf(p, len, "%02d%02d%02d%02d%02d%02dZ",
308 ts->tm_year % 100, ts->tm_mon + 1,
309 ts->tm_mday, ts->tm_hour, ts->tm_min,
310 ts->tm_sec);
311 }
312
313 #ifdef CHARSET_EBCDIC
314 ebcdic2ascii(tmps->data, tmps->data, tmps->length);
315 #endif
316 return tmps;
317 err:
318 if (tmps != s)
319 ASN1_STRING_free(tmps);
320 return NULL;
321 }
322
ASN1_TIME_set(ASN1_TIME * s,time_t t)323 ASN1_TIME *ASN1_TIME_set(ASN1_TIME *s, time_t t)
324 {
325 return ASN1_TIME_adj(s, t, 0, 0);
326 }
327
ASN1_TIME_adj(ASN1_TIME * s,time_t t,int offset_day,long offset_sec)328 ASN1_TIME *ASN1_TIME_adj(ASN1_TIME *s, time_t t,
329 int offset_day, long offset_sec)
330 {
331 struct tm *ts;
332 struct tm data;
333
334 ts = OPENSSL_gmtime(&t, &data);
335 if (ts == NULL) {
336 ERR_raise(ERR_LIB_ASN1, ASN1_R_ERROR_GETTING_TIME);
337 return NULL;
338 }
339 if (offset_day || offset_sec) {
340 if (!OPENSSL_gmtime_adj(ts, offset_day, offset_sec))
341 return NULL;
342 }
343 return ossl_asn1_time_from_tm(s, ts, V_ASN1_UNDEF);
344 }
345
ASN1_TIME_check(const ASN1_TIME * t)346 int ASN1_TIME_check(const ASN1_TIME *t)
347 {
348 if (t->type == V_ASN1_GENERALIZEDTIME)
349 return ASN1_GENERALIZEDTIME_check(t);
350 else if (t->type == V_ASN1_UTCTIME)
351 return ASN1_UTCTIME_check(t);
352 return 0;
353 }
354
355 /* Convert an ASN1_TIME structure to GeneralizedTime */
ASN1_TIME_to_generalizedtime(const ASN1_TIME * t,ASN1_GENERALIZEDTIME ** out)356 ASN1_GENERALIZEDTIME *ASN1_TIME_to_generalizedtime(const ASN1_TIME *t,
357 ASN1_GENERALIZEDTIME **out)
358 {
359 ASN1_GENERALIZEDTIME *ret = NULL;
360 struct tm tm;
361
362 if (!ASN1_TIME_to_tm(t, &tm))
363 return NULL;
364
365 if (out != NULL)
366 ret = *out;
367
368 ret = ossl_asn1_time_from_tm(ret, &tm, V_ASN1_GENERALIZEDTIME);
369
370 if (out != NULL && ret != NULL)
371 *out = ret;
372
373 return ret;
374 }
375
ASN1_TIME_set_string(ASN1_TIME * s,const char * str)376 int ASN1_TIME_set_string(ASN1_TIME *s, const char *str)
377 {
378 /* Try UTC, if that fails, try GENERALIZED */
379 if (ASN1_UTCTIME_set_string(s, str))
380 return 1;
381 return ASN1_GENERALIZEDTIME_set_string(s, str);
382 }
383
ASN1_TIME_set_string_X509(ASN1_TIME * s,const char * str)384 int ASN1_TIME_set_string_X509(ASN1_TIME *s, const char *str)
385 {
386 ASN1_TIME t;
387 struct tm tm;
388 int rv = 0;
389
390 t.length = strlen(str);
391 t.data = (unsigned char *)str;
392 t.flags = ASN1_STRING_FLAG_X509_TIME;
393
394 t.type = V_ASN1_UTCTIME;
395
396 if (!ASN1_TIME_check(&t)) {
397 t.type = V_ASN1_GENERALIZEDTIME;
398 if (!ASN1_TIME_check(&t))
399 goto out;
400 }
401
402 /*
403 * Per RFC 5280 (section 4.1.2.5.), the valid input time
404 * strings should be encoded with the following rules:
405 *
406 * 1. UTC: YYMMDDHHMMSSZ, if YY < 50 (20YY) --> UTC: YYMMDDHHMMSSZ
407 * 2. UTC: YYMMDDHHMMSSZ, if YY >= 50 (19YY) --> UTC: YYMMDDHHMMSSZ
408 * 3. G'd: YYYYMMDDHHMMSSZ, if YYYY >= 2050 --> G'd: YYYYMMDDHHMMSSZ
409 * 4. G'd: YYYYMMDDHHMMSSZ, if YYYY < 2050 --> UTC: YYMMDDHHMMSSZ
410 *
411 * Only strings of the 4th rule should be reformatted, but since a
412 * UTC can only present [1950, 2050), so if the given time string
413 * is less than 1950 (e.g. 19230419000000Z), we do nothing...
414 */
415
416 if (s != NULL && t.type == V_ASN1_GENERALIZEDTIME) {
417 if (!ossl_asn1_time_to_tm(&tm, &t))
418 goto out;
419 if (is_utc(tm.tm_year)) {
420 t.length -= 2;
421 /*
422 * it's OK to let original t.data go since that's assigned
423 * to a piece of memory allocated outside of this function.
424 * new t.data would be freed after ASN1_STRING_copy is done.
425 */
426 t.data = OPENSSL_zalloc(t.length + 1);
427 if (t.data == NULL)
428 goto out;
429 memcpy(t.data, str + 2, t.length);
430 t.type = V_ASN1_UTCTIME;
431 }
432 }
433
434 if (s == NULL || ASN1_STRING_copy((ASN1_STRING *)s, (ASN1_STRING *)&t))
435 rv = 1;
436
437 if (t.data != (unsigned char *)str)
438 OPENSSL_free(t.data);
439 out:
440 return rv;
441 }
442
ASN1_TIME_to_tm(const ASN1_TIME * s,struct tm * tm)443 int ASN1_TIME_to_tm(const ASN1_TIME *s, struct tm *tm)
444 {
445 if (s == NULL) {
446 time_t now_t;
447
448 time(&now_t);
449 memset(tm, 0, sizeof(*tm));
450 if (OPENSSL_gmtime(&now_t, tm) != NULL)
451 return 1;
452 return 0;
453 }
454
455 return ossl_asn1_time_to_tm(tm, s);
456 }
457
ASN1_TIME_diff(int * pday,int * psec,const ASN1_TIME * from,const ASN1_TIME * to)458 int ASN1_TIME_diff(int *pday, int *psec,
459 const ASN1_TIME *from, const ASN1_TIME *to)
460 {
461 struct tm tm_from, tm_to;
462
463 if (!ASN1_TIME_to_tm(from, &tm_from))
464 return 0;
465 if (!ASN1_TIME_to_tm(to, &tm_to))
466 return 0;
467 return OPENSSL_gmtime_diff(pday, psec, &tm_from, &tm_to);
468 }
469
470 static const char _asn1_mon[12][4] = {
471 "Jan", "Feb", "Mar", "Apr", "May", "Jun",
472 "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
473 };
474
475 /* prints the time with the default date format (RFC 822) */
ASN1_TIME_print(BIO * bp,const ASN1_TIME * tm)476 int ASN1_TIME_print(BIO *bp, const ASN1_TIME *tm)
477 {
478 return ASN1_TIME_print_ex(bp, tm, ASN1_DTFLGS_RFC822);
479 }
480
481 /* 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)482 int ASN1_TIME_print_ex(BIO *bp, const ASN1_TIME *tm, unsigned long flags)
483 {
484 return ossl_asn1_time_print_ex(bp, tm, flags) > 0;
485 }
486
487
488 /* prints the time with the date format of ISO 8601 */
489 /* 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)490 int ossl_asn1_time_print_ex(BIO *bp, const ASN1_TIME *tm, unsigned long flags)
491 {
492 char *v;
493 int gmt = 0, l;
494 struct tm stm;
495 const char upper_z = 0x5A, period = 0x2E;
496
497 /* ossl_asn1_time_to_tm will check the time type */
498 if (!ossl_asn1_time_to_tm(&stm, tm))
499 return BIO_write(bp, "Bad time value", 14) ? -1 : 0;
500
501 l = tm->length;
502 v = (char *)tm->data;
503 if (v[l - 1] == upper_z)
504 gmt = 1;
505
506 if (tm->type == V_ASN1_GENERALIZEDTIME) {
507 char *f = NULL;
508 int f_len = 0;
509
510 /*
511 * Try to parse fractional seconds. '14' is the place of
512 * 'fraction point' in a GeneralizedTime string.
513 */
514 if (tm->length > 15 && v[14] == period) {
515 f = &v[14];
516 f_len = 1;
517 while (14 + f_len < l && ossl_ascii_isdigit(f[f_len]))
518 ++f_len;
519 }
520
521 if ((flags & ASN1_DTFLGS_TYPE_MASK) == ASN1_DTFLGS_ISO8601) {
522 return BIO_printf(bp, "%4d-%02d-%02d %02d:%02d:%02d%.*s%s",
523 stm.tm_year + 1900, stm.tm_mon + 1,
524 stm.tm_mday, stm.tm_hour,
525 stm.tm_min, stm.tm_sec, f_len, f,
526 (gmt ? "Z" : "")) > 0;
527 }
528 else {
529 return BIO_printf(bp, "%s %2d %02d:%02d:%02d%.*s %d%s",
530 _asn1_mon[stm.tm_mon], stm.tm_mday, stm.tm_hour,
531 stm.tm_min, stm.tm_sec, f_len, f, stm.tm_year + 1900,
532 (gmt ? " GMT" : "")) > 0;
533 }
534 } else {
535 if ((flags & ASN1_DTFLGS_TYPE_MASK) == ASN1_DTFLGS_ISO8601) {
536 return BIO_printf(bp, "%4d-%02d-%02d %02d:%02d:%02d%s",
537 stm.tm_year + 1900, stm.tm_mon + 1,
538 stm.tm_mday, stm.tm_hour,
539 stm.tm_min, stm.tm_sec,
540 (gmt ? "Z" : "")) > 0;
541 }
542 else {
543 return BIO_printf(bp, "%s %2d %02d:%02d:%02d %d%s",
544 _asn1_mon[stm.tm_mon], stm.tm_mday, stm.tm_hour,
545 stm.tm_min, stm.tm_sec, stm.tm_year + 1900,
546 (gmt ? " GMT" : "")) > 0;
547 }
548 }
549 }
550
ASN1_TIME_cmp_time_t(const ASN1_TIME * s,time_t t)551 int ASN1_TIME_cmp_time_t(const ASN1_TIME *s, time_t t)
552 {
553 struct tm stm, ttm;
554 int day, sec;
555
556 if (!ASN1_TIME_to_tm(s, &stm))
557 return -2;
558
559 if (!OPENSSL_gmtime(&t, &ttm))
560 return -2;
561
562 if (!OPENSSL_gmtime_diff(&day, &sec, &ttm, &stm))
563 return -2;
564
565 if (day > 0 || sec > 0)
566 return 1;
567 if (day < 0 || sec < 0)
568 return -1;
569 return 0;
570 }
571
ASN1_TIME_normalize(ASN1_TIME * t)572 int ASN1_TIME_normalize(ASN1_TIME *t)
573 {
574 struct tm tm;
575
576 if (t == NULL || !ASN1_TIME_to_tm(t, &tm))
577 return 0;
578
579 return ossl_asn1_time_from_tm(t, &tm, V_ASN1_UNDEF) != NULL;
580 }
581
ASN1_TIME_compare(const ASN1_TIME * a,const ASN1_TIME * b)582 int ASN1_TIME_compare(const ASN1_TIME *a, const ASN1_TIME *b)
583 {
584 int day, sec;
585
586 if (!ASN1_TIME_diff(&day, &sec, b, a))
587 return -2;
588 if (day > 0 || sec > 0)
589 return 1;
590 if (day < 0 || sec < 0)
591 return -1;
592 return 0;
593 }
594
