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diff --git a/doc/man3/ASN1_TIME_set.pod b/doc/man3/ASN1_TIME_set.pod new file mode 100644 index 000000000000..a083ebfd1bd4 --- /dev/null +++ b/doc/man3/ASN1_TIME_set.pod @@ -0,0 +1,258 @@ +=pod + +=head1 NAME + +ASN1_TIME_set, ASN1_UTCTIME_set, ASN1_GENERALIZEDTIME_set, +ASN1_TIME_adj, ASN1_UTCTIME_adj, ASN1_GENERALIZEDTIME_adj, +ASN1_TIME_check, ASN1_UTCTIME_check, ASN1_GENERALIZEDTIME_check, +ASN1_TIME_set_string, ASN1_UTCTIME_set_string, ASN1_GENERALIZEDTIME_set_string, +ASN1_TIME_set_string_X509, +ASN1_TIME_normalize, +ASN1_TIME_to_tm, +ASN1_TIME_print, ASN1_UTCTIME_print, ASN1_GENERALIZEDTIME_print, +ASN1_TIME_diff, +ASN1_TIME_cmp_time_t, ASN1_UTCTIME_cmp_time_t, +ASN1_TIME_compare, +ASN1_TIME_to_generalizedtime - ASN.1 Time functions + +=head1 SYNOPSIS + + ASN1_TIME *ASN1_TIME_set(ASN1_TIME *s, time_t t); + ASN1_UTCTIME *ASN1_UTCTIME_set(ASN1_UTCTIME *s, time_t t); + ASN1_GENERALIZEDTIME *ASN1_GENERALIZEDTIME_set(ASN1_GENERALIZEDTIME *s, + time_t t); + + ASN1_TIME *ASN1_TIME_adj(ASN1_TIME *s, time_t t, int offset_day, + long offset_sec); + ASN1_UTCTIME *ASN1_UTCTIME_adj(ASN1_UTCTIME *s, time_t t, + int offset_day, long offset_sec); + ASN1_GENERALIZEDTIME *ASN1_GENERALIZEDTIME_adj(ASN1_GENERALIZEDTIME *s, + time_t t, int offset_day, + long offset_sec); + + int ASN1_TIME_set_string(ASN1_TIME *s, const char *str); + int ASN1_TIME_set_string_X509(ASN1_TIME *s, const char *str); + int ASN1_UTCTIME_set_string(ASN1_UTCTIME *s, const char *str); + int ASN1_GENERALIZEDTIME_set_string(ASN1_GENERALIZEDTIME *s, + const char *str); + + int ASN1_TIME_normalize(ASN1_TIME *s); + + int ASN1_TIME_check(const ASN1_TIME *t); + int ASN1_UTCTIME_check(const ASN1_UTCTIME *t); + int ASN1_GENERALIZEDTIME_check(const ASN1_GENERALIZEDTIME *t); + + int ASN1_TIME_print(BIO *b, const ASN1_TIME *s); + int ASN1_UTCTIME_print(BIO *b, const ASN1_UTCTIME *s); + int ASN1_GENERALIZEDTIME_print(BIO *b, const ASN1_GENERALIZEDTIME *s); + + int ASN1_TIME_to_tm(const ASN1_TIME *s, struct tm *tm); + int ASN1_TIME_diff(int *pday, int *psec, const ASN1_TIME *from, + const ASN1_TIME *to); + + int ASN1_TIME_cmp_time_t(const ASN1_TIME *s, time_t t); + int ASN1_UTCTIME_cmp_time_t(const ASN1_UTCTIME *s, time_t t); + + int ASN1_TIME_compare(const ASN1_TIME *a, const ASN1_TIME *b); + + ASN1_GENERALIZEDTIME *ASN1_TIME_to_generalizedtime(ASN1_TIME *t, + ASN1_GENERALIZEDTIME **out); + +=head1 DESCRIPTION + +The ASN1_TIME_set(), ASN1_UTCTIME_set() and ASN1_GENERALIZEDTIME_set() +functions set the structure B<s> to the time represented by the time_t +value B<t>. If B<s> is NULL a new time structure is allocated and returned. + +The ASN1_TIME_adj(), ASN1_UTCTIME_adj() and ASN1_GENERALIZEDTIME_adj() +functions set the time structure B<s> to the time represented +by the time B<offset_day> and B<offset_sec> after the time_t value B<t>. +The values of B<offset_day> or B<offset_sec> can be negative to set a +time before B<t>. The B<offset_sec> value can also exceed the number of +seconds in a day. If B<s> is NULL a new structure is allocated +and returned. + +The ASN1_TIME_set_string(), ASN1_UTCTIME_set_string() and +ASN1_GENERALIZEDTIME_set_string() functions set the time structure B<s> +to the time represented by string B<str> which must be in appropriate ASN.1 +time format (for example YYMMDDHHMMSSZ or YYYYMMDDHHMMSSZ). If B<s> is NULL +this function performs a format check on B<str> only. The string B<str> +is copied into B<s>. + +ASN1_TIME_set_string_X509() sets ASN1_TIME structure B<s> to the time +represented by string B<str> which must be in appropriate time format +that RFC 5280 requires, which means it only allows YYMMDDHHMMSSZ and +YYYYMMDDHHMMSSZ (leap second is rejected), all other ASN.1 time format +are not allowed. If B<s> is NULL this function performs a format check +on B<str> only. + +The ASN1_TIME_normalize() function converts an ASN1_GENERALIZEDTIME or +ASN1_UTCTIME into a time value that can be used in a certificate. It +should be used after the ASN1_TIME_set_string() functions and before +ASN1_TIME_print() functions to get consistent (i.e. GMT) results. + +The ASN1_TIME_check(), ASN1_UTCTIME_check() and ASN1_GENERALIZEDTIME_check() +functions check the syntax of the time structure B<s>. + +The ASN1_TIME_print(), ASN1_UTCTIME_print() and ASN1_GENERALIZEDTIME_print() +functions print the time structure B<s> to BIO B<b> in human readable +format. It will be of the format MMM DD HH:MM:SS YYYY [GMT], for example +"Feb 3 00:55:52 2015 GMT" it does not include a newline. If the time +structure has invalid format it prints out "Bad time value" and returns +an error. The output for generalized time may include a fractional part +following the second. + +ASN1_TIME_to_tm() converts the time B<s> to the standard B<tm> structure. +If B<s> is NULL, then the current time is converted. The output time is GMT. +The B<tm_sec>, B<tm_min>, B<tm_hour>, B<tm_mday>, B<tm_wday>, B<tm_yday>, +B<tm_mon> and B<tm_year> fields of B<tm> structure are set to proper values, +whereas all other fields are set to 0. If B<tm> is NULL this function performs +a format check on B<s> only. If B<s> is in Generalized format with fractional +seconds, e.g. YYYYMMDDHHMMSS.SSSZ, the fractional seconds will be lost while +converting B<s> to B<tm> structure. + +ASN1_TIME_diff() sets B<*pday> and B<*psec> to the time difference between +B<from> and B<to>. If B<to> represents a time later than B<from> then +one or both (depending on the time difference) of B<*pday> and B<*psec> +will be positive. If B<to> represents a time earlier than B<from> then +one or both of B<*pday> and B<*psec> will be negative. If B<to> and B<from> +represent the same time then B<*pday> and B<*psec> will both be zero. +If both B<*pday> and B<*psec> are non-zero they will always have the same +sign. The value of B<*psec> will always be less than the number of seconds +in a day. If B<from> or B<to> is NULL the current time is used. + +The ASN1_TIME_cmp_time_t() and ASN1_UTCTIME_cmp_time_t() functions compare +the two times represented by the time structure B<s> and the time_t B<t>. + +The ASN1_TIME_compare() function compares the two times represented by the +time structures B<a> and B<b>. + +The ASN1_TIME_to_generalizedtime() function converts an ASN1_TIME to an +ASN1_GENERALIZEDTIME, regardless of year. If either B<out> or +B<*out> are NULL, then a new object is allocated and must be freed after use. + +=head1 NOTES + +The ASN1_TIME structure corresponds to the ASN.1 structure B<Time> +defined in RFC5280 et al. The time setting functions obey the rules outlined +in RFC5280: if the date can be represented by UTCTime it is used, else +GeneralizedTime is used. + +The ASN1_TIME, ASN1_UTCTIME and ASN1_GENERALIZEDTIME structures are represented +as an ASN1_STRING internally and can be freed up using ASN1_STRING_free(). + +The ASN1_TIME structure can represent years from 0000 to 9999 but no attempt +is made to correct ancient calendar changes (for example from Julian to +Gregorian calendars). + +ASN1_UTCTIME is limited to a year range of 1950 through 2049. + +Some applications add offset times directly to a time_t value and pass the +results to ASN1_TIME_set() (or equivalent). This can cause problems as the +time_t value can overflow on some systems resulting in unexpected results. +New applications should use ASN1_TIME_adj() instead and pass the offset value +in the B<offset_sec> and B<offset_day> parameters instead of directly +manipulating a time_t value. + +ASN1_TIME_adj() may change the type from ASN1_GENERALIZEDTIME to ASN1_UTCTIME, +or vice versa, based on the resulting year. The ASN1_GENERALIZEDTIME_adj() and +ASN1_UTCTIME_adj() functions will not modify the type of the return structure. + +It is recommended that functions starting with ASN1_TIME be used instead of +those starting with ASN1_UTCTIME or ASN1_GENERALIZEDTIME. The functions +starting with ASN1_UTCTIME and ASN1_GENERALIZEDTIME act only on that specific +time format. The functions starting with ASN1_TIME will operate on either +format. + +=head1 BUGS + +ASN1_TIME_print(), ASN1_UTCTIME_print() and ASN1_GENERALIZEDTIME_print() +do not print out the time zone: it either prints out "GMT" or nothing. But all +certificates complying with RFC5280 et al use GMT anyway. + +Use the ASN1_TIME_normalize() function to normalize the time value before +printing to get GMT results. + +=head1 EXAMPLES + +Set a time structure to one hour after the current time and print it out: + + #include <time.h> + #include <openssl/asn1.h> + + ASN1_TIME *tm; + time_t t; + BIO *b; + + t = time(NULL); + tm = ASN1_TIME_adj(NULL, t, 0, 60 * 60); + b = BIO_new_fp(stdout, BIO_NOCLOSE); + ASN1_TIME_print(b, tm); + ASN1_STRING_free(tm); + BIO_free(b); + +Determine if one time is later or sooner than the current time: + + int day, sec; + + if (!ASN1_TIME_diff(&day, &sec, NULL, to)) + /* Invalid time format */ + + if (day > 0 || sec > 0) + printf("Later\n"); + else if (day < 0 || sec < 0) + printf("Sooner\n"); + else + printf("Same\n"); + +=head1 RETURN VALUES + +ASN1_TIME_set(), ASN1_UTCTIME_set(), ASN1_GENERALIZEDTIME_set(), ASN1_TIME_adj(), +ASN1_UTCTIME_adj and ASN1_GENERALIZEDTIME_set return a pointer to a time structure +or NULL if an error occurred. + +ASN1_TIME_set_string(), ASN1_UTCTIME_set_string(), ASN1_GENERALIZEDTIME_set_string() +ASN1_TIME_set_string_X509() return 1 if the time value is successfully set and 0 otherwise. + +ASN1_TIME_normalize() returns 1 on success, and 0 on error. + +ASN1_TIME_check(), ASN1_UTCTIME_check and ASN1_GENERALIZEDTIME_check() return 1 +if the structure is syntactically correct and 0 otherwise. + +ASN1_TIME_print(), ASN1_UTCTIME_print() and ASN1_GENERALIZEDTIME_print() return 1 +if the time is successfully printed out and 0 if an error occurred (I/O error or +invalid time format). + +ASN1_TIME_to_tm() returns 1 if the time is successfully parsed and 0 if an +error occurred (invalid time format). + +ASN1_TIME_diff() returns 1 for success and 0 for failure. It can fail if the +passed-in time structure has invalid syntax, for example. + +ASN1_TIME_cmp_time_t() and ASN1_UTCTIME_cmp_time_t() return -1 if B<s> is +before B<t>, 0 if B<s> equals B<t>, or 1 if B<s> is after B<t>. -2 is returned +on error. + +ASN1_TIME_compare() returns -1 if B<a> is before B<b>, 0 if B<a> equals B<b>, or 1 if B<a> is after B<b>. -2 is returned on error. + +ASN1_TIME_to_generalizedtime() returns a pointer to +the appropriate time structure on success or NULL if an error occurred. + +=head1 HISTORY + +The ASN1_TIME_to_tm() function was added in OpenSSL 1.1.1. +The ASN1_TIME_set_string_X509() function was added in OpenSSL 1.1.1. +The ASN1_TIME_normalize() function was added in OpenSSL 1.1.1. +The ASN1_TIME_cmp_time_t() function was added in OpenSSL 1.1.1. +The ASN1_TIME_compare() function was added in OpenSSL 1.1.1. + +=head1 COPYRIGHT + +Copyright 2015-2018 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 +L<https://www.openssl.org/source/license.html>. + +=cut |