Overview #A value of the GeneralizedTime LDAPSyntaxes is a character string representing a date and time.
The LDAP-specific encoding of a value of this syntax is a restriction of the format defined in ISO 8601, and is described by the following ABNF:
GeneralizedTime = century year month day hour [ minute [ second / leap-second ] ] [ fraction ] g-time-zone century = 2(%x30-39) ; "00" to "99" year = 2(%x30-39) ; "00" to "99" month = ( %x30 %x31-39 ) ; "01" (January) to "09" / ( %x31 %x30-32 ) ; "10" to "12" day = ( %x30 %x31-39 ) ; "01" to "09" / ( %x31-32 %x30-39 ) ; "10" to "29" / ( %x33 %x30-31 ) ; "30" to "31" hour = ( %x30-31 %x30-39 ) / ( %x32 %x30-33 ) ; "00" to "23" minute = %x30-35 %x30-39 ; "00" to "59" second = ( %x30-35 %x30-39 ) ; "00" to "59" leap-second = ( %x36 %x30 ) ; "60" fraction = ( DOT / COMMA ) 1*(%x30-39) g-time-zone = %x5A ; "Z" / g-differential g-differential = ( MINUS / PLUS ) hour [ minute ] MINUS = %x2D ; minus sign ("-")The <DOT>, <COMMA>, and <PLUS> rules are defined in RFC 4512.
The above ABNF allows character strings that do not represent valid dates (in the Gregorian calendar) and/or valid times (e.g., February 31, 1994). Such character strings SHOULD be considered invalid for this syntax.
The time value represents coordinated universal time (equivalent to Greenwich Mean Time) if the "Z" form of <g-time-zone> is used; otherwise, the value represents a local time in the time zone indicated by <g-differential>. In the latter case, coordinated universal time can be calculated by subtracting the differential from the local time. The "Z" form of <g-time-zone> SHOULD be used in preference to <g-differential>.
If <minute> is omitted, then <fraction> represents a fraction of an hour; otherwise, if <second> and <leap-second> are omitted, then <fraction> represents a fraction of a minute; otherwise, <fraction> represents a fraction of a second.
Both example values represent the same coordinated universal time: 10:32 AM, December 16, 1994.
This syntax corresponds to the GeneralizedTime ASN.1 type from ASN.1, with the constraint that local time without a differential SHALL NOT be used.
The LDAP-specific encoding of a value of this syntax is defined by the GeneralizedTime rule in RFC 4512.
More Information #There might be more information for this subject on one of the following:
- Certificate Validity Period
- Converting AD Times
- Edirectory Anomalies
- Microsoft Active Directory Syntax
- Microsoft TIME