diff options
Diffstat (limited to 'third_party/heimdal/lib/asn1/timegm.c')
| -rw-r--r-- | third_party/heimdal/lib/asn1/timegm.c | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/third_party/heimdal/lib/asn1/timegm.c b/third_party/heimdal/lib/asn1/timegm.c new file mode 100644 index 0000000..4746fa8 --- /dev/null +++ b/third_party/heimdal/lib/asn1/timegm.c @@ -0,0 +1,136 @@ +/* + * Copyright (c) 1997 Kungliga Tekniska Högskolan + * (Royal Institute of Technology, Stockholm, Sweden). + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * 3. Neither the name of the Institute nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include "der_locl.h" + +#define ASN1_MAX_YEAR 2000 + +static int +is_leap(unsigned y) +{ + y += 1900; + return (y % 4) == 0 && ((y % 100) != 0 || (y % 400) == 0); +} + +static const unsigned ndays[2][12] ={ + {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}, + {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}}; + +/* + * This is a simplifed version of timegm(3) that doesn't accept out of + * bound values that timegm(3) normally accepts but those are not + * valid in asn1 encodings. + */ + +time_t +_der_timegm (struct tm *tm) +{ + time_t res = 0; + int i; + + /* + * See comment in _der_gmtime + */ + if (tm->tm_year > ASN1_MAX_YEAR) + return 0; + + if (tm->tm_year < 0) + return -1; + if (tm->tm_mon < 0 || tm->tm_mon > 11) + return -1; + if (tm->tm_mday < 1 || tm->tm_mday > (int)ndays[is_leap(tm->tm_year)][tm->tm_mon]) + return -1; + if (tm->tm_hour < 0 || tm->tm_hour > 23) + return -1; + if (tm->tm_min < 0 || tm->tm_min > 59) + return -1; + if (tm->tm_sec < 0 || tm->tm_sec > 59) + return -1; + + for (i = 70; i < tm->tm_year; ++i) + res += is_leap(i) ? 366 : 365; + + for (i = 0; i < tm->tm_mon; ++i) + res += ndays[is_leap(tm->tm_year)][i]; + res += tm->tm_mday - 1; + res *= 24; + res += tm->tm_hour; + res *= 60; + res += tm->tm_min; + res *= 60; + res += tm->tm_sec; + return res; +} + +struct tm * +_der_gmtime(time_t t, struct tm *tm) +{ + time_t secday = t % (3600 * 24); + time_t days = t / (3600 * 24); + + memset(tm, 0, sizeof(*tm)); + + tm->tm_sec = secday % 60; + tm->tm_min = (secday % 3600) / 60; + tm->tm_hour = (int)(secday / 3600); + + /* + * Refuse to calculate time ~ 2000 years into the future, this is + * not possible for systems where time_t is a int32_t, however, + * when time_t is a int64_t, that can happen, and this becomes a + * denial of sevice. + */ + if (days > (ASN1_MAX_YEAR * 365)) + return NULL; + + tm->tm_year = 70; + while(1) { + unsigned dayinyear = (is_leap(tm->tm_year) ? 366 : 365); + if (days < dayinyear) + break; + tm->tm_year += 1; + days -= dayinyear; + } + tm->tm_mon = 0; + + while (1) { + unsigned daysinmonth = ndays[is_leap(tm->tm_year)][tm->tm_mon]; + if (days < daysinmonth) + break; + days -= daysinmonth; + tm->tm_mon++; + } + tm->tm_mday = (int)(days + 1); + + return tm; +} |