/* * Copyright 1999-2017 The OpenSSL Project Authors. All Rights Reserved. * * Licensed under the OpenSSL license (the "License"). You may not use * this file except in compliance with the License. You can obtain a copy * in the file LICENSE in the source distribution or at * https://www.openssl.org/source/license.html */ /*- * This is an implementation of the ASN1 Time structure which is: * Time ::= CHOICE { * utcTime UTCTime, * generalTime GeneralizedTime } */ #include #include #include #include "internal/cryptlib.h" #include #include "asn1_locl.h" IMPLEMENT_ASN1_MSTRING(ASN1_TIME, B_ASN1_TIME) IMPLEMENT_ASN1_FUNCTIONS(ASN1_TIME) static int is_utc(const int year) { if (50 <= year && year <= 149) return 1; return 0; } static int leap_year(const int year) { if (year % 400 == 0 || (year % 100 != 0 && year % 4 == 0)) return 1; return 0; } /* * Compute the day of the week and the day of the year from the year, month * and day. The day of the year is straightforward, the day of the week uses * a form of Zeller's congruence. For this months start with March and are * numbered 4 through 15. */ static void determine_days(struct tm *tm) { static const int ydays[12] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 }; int y = tm->tm_year + 1900; int m = tm->tm_mon; int d = tm->tm_mday; int c; tm->tm_yday = ydays[m] + d - 1; if (m >= 2) { /* March and onwards can be one day further into the year */ tm->tm_yday += leap_year(y); m += 2; } else { /* Treat January and February as part of the previous year */ m += 14; y--; } c = y / 100; y %= 100; /* Zeller's congruance */ tm->tm_wday = (d + (13 * m) / 5 + y + y / 4 + c / 4 + 5 * c + 6) % 7; } int asn1_time_to_tm(struct tm *tm, const ASN1_TIME *d) { static const int min[9] = { 0, 0, 1, 1, 0, 0, 0, 0, 0 }; static const int max[9] = { 99, 99, 12, 31, 23, 59, 59, 12, 59 }; static const int mdays[12] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }; char *a; int n, i, i2, l, o, min_l = 11, strict = 0, end = 6, btz = 5, md; struct tm tmp; /* * ASN1_STRING_FLAG_X509_TIME is used to enforce RFC 5280 * time string format, in which: * * 1. "seconds" is a 'MUST' * 2. "Zulu" timezone is a 'MUST' * 3. "+|-" is not allowed to indicate a time zone */ if (d->type == V_ASN1_UTCTIME) { if (d->flags & ASN1_STRING_FLAG_X509_TIME) { min_l = 13; strict = 1; } } else if (d->type == V_ASN1_GENERALIZEDTIME) { end = 7; btz = 6; if (d->flags & ASN1_STRING_FLAG_X509_TIME) { min_l = 15; strict = 1; } else { min_l = 13; } } else { return 0; } l = d->length; a = (char *)d->data; o = 0; memset(&tmp, 0, sizeof(tmp)); /* * GENERALIZEDTIME is similar to UTCTIME except the year is represented * as YYYY. This stuff treats everything as a two digit field so make * first two fields 00 to 99 */ if (l < min_l) goto err; for (i = 0; i < end; i++) { if (!strict && (i == btz) && ((a[o] == 'Z') || (a[o] == '+') || (a[o] == '-'))) { i++; break; } if (!isdigit(a[o])) goto err; n = a[o] - '0'; /* incomplete 2-digital number */ if (++o == l) goto err; if (!isdigit(a[o])) goto err; n = (n * 10) + a[o] - '0'; /* no more bytes to read, but we haven't seen time-zone yet */ if (++o == l) goto err; i2 = (d->type == V_ASN1_UTCTIME) ? i + 1 : i; if ((n < min[i2]) || (n > max[i2])) goto err; switch (i2) { case 0: /* UTC will never be here */ tmp.tm_year = n * 100 - 1900; break; case 1: if (d->type == V_ASN1_UTCTIME) tmp.tm_year = n < 50 ? n + 100 : n; else tmp.tm_year += n; break; case 2: tmp.tm_mon = n - 1; break; case 3: /* check if tm_mday is valid in tm_mon */ if (tmp.tm_mon == 1) { /* it's February */ md = mdays[1] + leap_year(tmp.tm_year + 1900); } else { md = mdays[tmp.tm_mon]; } if (n > md) goto err; tmp.tm_mday = n; determine_days(&tmp); break; case 4: tmp.tm_hour = n; break; case 5: tmp.tm_min = n; break; case 6: tmp.tm_sec = n; break; } } /* * Optional fractional seconds: decimal point followed by one or more * digits. */ if (d->type == V_ASN1_GENERALIZEDTIME && a[o] == '.') { if (strict) /* RFC 5280 forbids fractional seconds */ goto err; if (++o == l) goto err; i = o; while ((o < l) && isdigit(a[o])) o++; /* Must have at least one digit after decimal point */ if (i == o) goto err; /* no more bytes to read, but we haven't seen time-zone yet */ if (o == l) goto err; } /* * 'o' will never point to '\0' at this point, the only chance * 'o' can point to '\0' is either the subsequent if or the first * else if is true. */ if (a[o] == 'Z') { o++; } else if (!strict && ((a[o] == '+') || (a[o] == '-'))) { int offsign = a[o] == '-' ? 1 : -1; int offset = 0; o++; /* * if not equal, no need to do subsequent checks * since the following for-loop will add 'o' by 4 * and the final return statement will check if 'l' * and 'o' are equal. */ if (o + 4 != l) goto err; for (i = end; i < end + 2; i++) { if (!isdigit(a[o])) goto err; n = a[o] - '0'; o++; if (!isdigit(a[o])) goto err; n = (n * 10) + a[o] - '0'; i2 = (d->type == V_ASN1_UTCTIME) ? i + 1 : i; if ((n < min[i2]) || (n > max[i2])) goto err; /* if tm is NULL, no need to adjust */ if (tm != NULL) { if (i == end) offset = n * 3600; else if (i == end + 1) offset += n * 60; } o++; } if (offset && !OPENSSL_gmtime_adj(&tmp, 0, offset * offsign)) goto err; } else { /* not Z, or not +/- in non-strict mode */ goto err; } if (o == l) { /* success, check if tm should be filled */ if (tm != NULL) *tm = tmp; return 1; } err: return 0; } ASN1_TIME *asn1_time_from_tm(ASN1_TIME *s, struct tm *ts, int type) { char* p; ASN1_TIME *tmps = NULL; const size_t len = 20; if (type == V_ASN1_UNDEF) { if (is_utc(ts->tm_year)) type = V_ASN1_UTCTIME; else type = V_ASN1_GENERALIZEDTIME; } else if (type == V_ASN1_UTCTIME) { if (!is_utc(ts->tm_year)) goto err; } else if (type != V_ASN1_GENERALIZEDTIME) { goto err; } if (s == NULL) tmps = ASN1_STRING_new(); else tmps = s; if (tmps == NULL) return NULL; if (!ASN1_STRING_set(tmps, NULL, len)) goto err; tmps->type = type; p = (char*)tmps->data; if (type == V_ASN1_GENERALIZEDTIME) tmps->length = BIO_snprintf(p, len, "%04d%02d%02d%02d%02d%02dZ", ts->tm_year + 1900, ts->tm_mon + 1, ts->tm_mday, ts->tm_hour, ts->tm_min, ts->tm_sec); else tmps->length = BIO_snprintf(p, len, "%02d%02d%02d%02d%02d%02dZ", ts->tm_year % 100, ts->tm_mon + 1, ts->tm_mday, ts->tm_hour, ts->tm_min, ts->tm_sec); #ifdef CHARSET_EBCDIC_not ebcdic2ascii(tmps->data, tmps->data, tmps->length); #endif return tmps; err: if (tmps != s) ASN1_STRING_free(tmps); return NULL; } ASN1_TIME *ASN1_TIME_set(ASN1_TIME *s, time_t t) { return ASN1_TIME_adj(s, t, 0, 0); } ASN1_TIME *ASN1_TIME_adj(ASN1_TIME *s, time_t t, int offset_day, long offset_sec) { struct tm *ts; struct tm data; ts = OPENSSL_gmtime(&t, &data); if (ts == NULL) { ASN1err(ASN1_F_ASN1_TIME_ADJ, ASN1_R_ERROR_GETTING_TIME); return NULL; } if (offset_day || offset_sec) { if (!OPENSSL_gmtime_adj(ts, offset_day, offset_sec)) return NULL; } return asn1_time_from_tm(s, ts, V_ASN1_UNDEF); } int ASN1_TIME_check(const ASN1_TIME *t) { if (t->type == V_ASN1_GENERALIZEDTIME) return ASN1_GENERALIZEDTIME_check(t); else if (t->type == V_ASN1_UTCTIME) return ASN1_UTCTIME_check(t); return 0; } /* Convert an ASN1_TIME structure to GeneralizedTime */ ASN1_GENERALIZEDTIME *ASN1_TIME_to_generalizedtime(const ASN1_TIME *t, ASN1_GENERALIZEDTIME **out) { ASN1_GENERALIZEDTIME *ret = NULL; struct tm tm; if (!ASN1_TIME_to_tm(t, &tm)) return NULL; if (out != NULL) ret = *out; ret = asn1_time_from_tm(ret, &tm, V_ASN1_GENERALIZEDTIME); if (out != NULL && ret != NULL) *out = ret; return ret; } int ASN1_TIME_set_string(ASN1_TIME *s, const char *str) { /* Try UTC, if that fails, try GENERALIZED */ if (ASN1_UTCTIME_set_string(s, str)) return 1; return ASN1_GENERALIZEDTIME_set_string(s, str); } int ASN1_TIME_set_string_X509(ASN1_TIME *s, const char *str) { ASN1_TIME t; struct tm tm; int rv = 0; t.length = strlen(str); t.data = (unsigned char *)str; t.flags = ASN1_STRING_FLAG_X509_TIME; t.type = V_ASN1_UTCTIME; if (!ASN1_TIME_check(&t)) { t.type = V_ASN1_GENERALIZEDTIME; if (!ASN1_TIME_check(&t)) goto out; } /* * Per RFC 5280 (section 4.1.2.5.), the valid input time * strings should be encoded with the following rules: * * 1. UTC: YYMMDDHHMMSSZ, if YY < 50 (20YY) --> UTC: YYMMDDHHMMSSZ * 2. UTC: YYMMDDHHMMSSZ, if YY >= 50 (19YY) --> UTC: YYMMDDHHMMSSZ * 3. G'd: YYYYMMDDHHMMSSZ, if YYYY >= 2050 --> G'd: YYYYMMDDHHMMSSZ * 4. G'd: YYYYMMDDHHMMSSZ, if YYYY < 2050 --> UTC: YYMMDDHHMMSSZ * * Only strings of the 4th rule should be reformatted, but since a * UTC can only present [1950, 2050), so if the given time string * is less than 1950 (e.g. 19230419000000Z), we do nothing... */ if (s != NULL && t.type == V_ASN1_GENERALIZEDTIME) { if (!asn1_time_to_tm(&tm, &t)) goto out; if (is_utc(tm.tm_year)) { t.length -= 2; /* * it's OK to let original t.data go since that's assigned * to a piece of memory allocated outside of this function. * new t.data would be freed after ASN1_STRING_copy is done. */ t.data = OPENSSL_zalloc(t.length + 1); if (t.data == NULL) goto out; memcpy(t.data, str + 2, t.length); t.type = V_ASN1_UTCTIME; } } if (s == NULL || ASN1_STRING_copy((ASN1_STRING *)s, (ASN1_STRING *)&t)) rv = 1; if (t.data != (unsigned char *)str) OPENSSL_free(t.data); out: return rv; } int ASN1_TIME_to_tm(const ASN1_TIME *s, struct tm *tm) { if (s == NULL) { time_t now_t; time(&now_t); memset(tm, 0, sizeof(*tm)); if (OPENSSL_gmtime(&now_t, tm) != NULL) return 1; return 0; } return asn1_time_to_tm(tm, s); } int ASN1_TIME_diff(int *pday, int *psec, const ASN1_TIME *from, const ASN1_TIME *to) { struct tm tm_from, tm_to; if (!ASN1_TIME_to_tm(from, &tm_from)) return 0; if (!ASN1_TIME_to_tm(to, &tm_to)) return 0; return OPENSSL_gmtime_diff(pday, psec, &tm_from, &tm_to); } static const char _asn1_mon[12][4] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" }; int ASN1_TIME_print(BIO *bp, const ASN1_TIME *tm) { char *v; int gmt = 0, l; struct tm stm; if (!asn1_time_to_tm(&stm, tm)) { /* asn1_time_to_tm will check the time type */ goto err; } l = tm->length; v = (char *)tm->data; if (v[l - 1] == 'Z') gmt = 1; if (tm->type == V_ASN1_GENERALIZEDTIME) { char *f = NULL; int f_len = 0; /* * Try to parse fractional seconds. '14' is the place of * 'fraction point' in a GeneralizedTime string. */ if (tm->length > 15 && v[14] == '.') { f = &v[14]; f_len = 1; while (14 + f_len < l && isdigit(f[f_len])) ++f_len; } return BIO_printf(bp, "%s %2d %02d:%02d:%02d%.*s %d%s", _asn1_mon[stm.tm_mon], stm.tm_mday, stm.tm_hour, stm.tm_min, stm.tm_sec, f_len, f, stm.tm_year + 1900, (gmt ? " GMT" : "")) > 0; } else { return BIO_printf(bp, "%s %2d %02d:%02d:%02d %d%s", _asn1_mon[stm.tm_mon], stm.tm_mday, stm.tm_hour, stm.tm_min, stm.tm_sec, stm.tm_year + 1900, (gmt ? " GMT" : "")) > 0; } err: BIO_write(bp, "Bad time value", 14); return 0; } int ASN1_TIME_cmp_time_t(const ASN1_TIME *s, time_t t) { struct tm stm, ttm; int day, sec; if (!ASN1_TIME_to_tm(s, &stm)) return -2; if (!OPENSSL_gmtime(&t, &ttm)) return -2; if (!OPENSSL_gmtime_diff(&day, &sec, &ttm, &stm)) return -2; if (day > 0 || sec > 0) return 1; if (day < 0 || sec < 0) return -1; return 0; } int ASN1_TIME_normalize(ASN1_TIME *t) { struct tm tm; if (!ASN1_TIME_to_tm(t, &tm)) return 0; return asn1_time_from_tm(t, &tm, V_ASN1_UNDEF) != NULL; } int ASN1_TIME_compare(const ASN1_TIME *a, const ASN1_TIME *b) { int day, sec; if (!ASN1_TIME_diff(&day, &sec, a, b)) return -2; if (day > 0 || sec > 0) return 1; if (day < 0 || sec < 0) return -1; return 0; }