xref: /dragonfly/lib/libutil/login_times.3 (revision 984263bc)
1.\" Copyright (c) 1995 David Nugent <davidn@blaze.net.au>
2.\" All rights reserved.
3.\"
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13.\" 3. This work was done expressly for inclusion into FreeBSD.  Other use
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15.\" 4. Absolutely no warranty of function or purpose is made by the author
16.\"    David Nugent.
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20.\" $FreeBSD: src/lib/libutil/login_times.3,v 1.8.2.5 2001/12/17 10:08:32 ru Exp $
21.\"
22.Dd January 2, 1997
23.Os
24.Dt LOGIN_TIMES 3
25.Sh NAME
26.Nm parse_lt ,
27.Nm in_ltm ,
28.Nm in_ltms
29.Nd functions for parsing and checking login time periods
30.Sh LIBRARY
31.Lb libutil
32.Sh SYNOPSIS
33.In sys/types.h
34.In time.h
35.In login_cap.h
36.Ft login_time_t
37.Fn parse_lt "const char *str"
38.Ft int
39.Fn in_ltm "const login_time_t *lt" "struct tm *t" "time_t *ends"
40.Ft int
41.Fn in_ltms "const login_time_t *lt" "struct tm *t" "time_t *ends"
42.Sh DESCRIPTION
43This set of functions may be used for parsing and checking login and
44session times against a predefined list of allowed login times as
45used in
46.Xr login.conf 5 .
47.Pp
48The format of allowed and disallowed session times specified in the
49.Ar times.allow
50and
51.Ar times.deny
52capability fields in a login class are comprised of a prefix which
53specifies one or more 2- or 3-character day codes, followed by
54a start and end time in 24 hour format separated by a hyphen.
55Day codes may be concatenated together to select specific days, or
56the special mnemonics "Any" and "All" (for any/all days of the week),
57"Wk" for any day of the week (excluding Saturdays and Sundays) and
58"Wd" for any weekend day may be used.
59.Pp
60For example, the following time period:
61.Dl MoThFrSa1400-2200
62is interpreted as Monday, Thursday through Saturday between the hours
63of 2pm and 10pm.
64.Dl Wd0600-1800
65means Saturday and Sunday, between the hours of 6am through 6pm, and
66.Dl Any0400-1600
67means any day of the week, between 4am and 4pm.
68.Pp
69Note that all time periods reference system local time.
70.Pp
71The
72.Fn parse_lt
73function converts the ASCII representation of a time period into
74a structure of type
75.Ft login_time_t .
76This is defined as:
77.Bd -literal
78typedef struct login_time
79{
80  u_short	lt_start;   /* Start time */
81  u_short	lt_end;	    /* End time */
82  u_char	lt_dow;	    /* Days of week */
83} login_time_t;
84.Ed
85.Pp
86The
87.Ar lt_start
88and
89.Ar lt_end
90fields contain the number of minutes past midnight at which the
91described period begins and ends.
92The
93.Ar lt_dow
94field is a bit field, containing one bit for each day of the week
95and one bit unused.
96A series
97.Em LTM_*
98macros may be used for testing bits individually and in combination.
99If no bits are set in this field - ie. it contains the value
100.Em LTM_NONE
101- then the entire period is assumed invalid.
102This is used as a convention to mark the termination of an array
103of login_time_t values.
104If
105.Fn parse_lt
106returns a
107.Ar login_time_t
108with
109.Ar lt_dow
110equal to
111.Em LTM_NONE
112then a parsing error was encountered.
113.Pp
114The remaining functions provide the ability to test a given time_t or
115struct tm value against a specific time period or array of time
116periods.
117.Fn in_ltm
118determines whether the given time described by the struct tm
119passed as the second parameter falls within the period described
120by the first parameter.
121A boolean value is returned, indicating whether or not the time
122specified falls within the period.
123If the time does fall within the time period, and the third
124parameter to the function is not NULL, the time at which the
125period ends relative to the time passed is returned.
126.Pp
127The
128.Fn in_ltms
129function is similar to
130.Fn in_ltm
131except that the first parameter must be a pointer to an array
132of login_time_t objects, which is up to LC_MAXTIMES (64)
133elements in length, and terminated by an element with its
134.Ar lt_dow
135field set to
136.Em LTM_NONE .
137.Sh RETURN VALUES
138.Fn parse_lt
139returns a filled in structure of type login_time_t containing the
140parsed time period.
141If a parsing error occurs, the lt_dow field is set to
142.Em LTM_NONE
143(i.e. 0).
144.Pp
145.Fn in_ltm
146returns non-zero if the given time falls within the period described
147by the login_time_t passed as the first parameter.
148.Pp
149.Fn in_ltms
150returns the index of the first time period found in which the given
151time falls, or -1 if none of them apply.
152.Sh SEE ALSO
153.Xr getcap 3 ,
154.Xr login_cap 3 ,
155.Xr login_class 3 ,
156.Xr login.conf 5 ,
157.Xr termcap 5
158