1.\" Copyright (c) 1995 David Nugent <davidn@blaze.net.au> 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, is permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice immediately at the beginning of the file, without modification, 9.\" this list of conditions, and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 3. This work was done expressly for inclusion into FreeBSD. Other use 14.\" is permitted provided this notation is included. 15.\" 4. Absolutely no warranty of function or purpose is made by the author 16.\" David Nugent. 17.\" 5. Modifications may be freely made to this file providing the above 18.\" conditions are met. 19.\" 20.\" $FreeBSD$ 21.\" 22.Dd January 2, 1997 23.Os FreeBSD 24.Dt LOGIN_OK 3 25.Sh NAME 26.Nm auth_ttyok , 27.Nm auth_hostok , 28.Nm auth_timeok 29.Nd functions for checking login class based login restrictions 30.Sh LIBRARY 31.Lb libutil 32.Sh SYNOPSIS 33.Fd #include <sys/types.h> 34.Fd #include <time.h> 35.Fd #include <login_cap.h> 36.Ft int 37.Fn auth_ttyok "login_cap_t *lc" "const char *tty" 38.Ft int 39.Fn auth_hostok "login_cap_t *lc" "const char *host" "char const *ip" 40.Ft int 41.Fn auth_timeok "login_cap_t *lc" "time_t t" 42.Sh DESCRIPTION 43This set of functions checks to see if login is allowed based on login 44class capability entries in the login database, 45.Xr login.conf 5 . 46.Pp 47.Fn auth_ttyok 48checks to see if the named tty is available to users of a specific 49class, and is either in the 50.Em ttys.allow 51access list, and not in 52the 53.Em ttys.deny 54access list. 55An empty 56.Em ttys.allow 57list (or if no such capability exists for 58the give login class) logins via any tty device are allowed unless 59the 60.Em ttys.deny 61list exists and is non-empty, and the device or its 62tty group (see 63.Xr ttys 5 ) 64is not in the list. 65Access to ttys may be allowed or restricted specifically by tty device 66name, a device name which includes a wildcard (e.g. ttyD* or cuaD*), 67or may name a ttygroup, when group=<name> tags have been assigned in 68.Pa /etc/ttys . 69Matching of ttys and ttygroups is case sensitive. 70Passing a 71.Dv NULL 72or empty string as the 73.Ar tty 74parameter causes the function to return a non-zero value. 75.Pp 76.Fn auth_hostok 77checks for any host restrictions for remote logins. 78The function checks on both a host name and IP address (given in its 79text form, typically n.n.n.n) against the 80.Em host.allow 81and 82.Em host.deny 83login class capabilities. 84As with ttys and their groups, wildcards and character classes may be 85used in the host allow and deny capability records. 86The 87.Xr fnmatch 3 88function is used for matching, and the matching on hostnames is case 89insensitive. 90Note that this function expects that the hostname is fully expanded 91(i.e. the local domain name added if necessary) and the IP address 92is in its canonical form. 93No hostname or address lookups are attempted. 94.Pp 95It is possible to call this function with either the hostname or 96the IP address missing (i.e. 97.Dv NULL ) 98and matching will be performed 99only on the basis of the parameter given. 100Passing 101.Dv NULL 102or empty strings in both parameters will result in 103a non-zero return value. 104.Pp 105The 106.Fn auth_timeok 107function checks to see that a given time value is within the 108.Em times.allow 109login class capability and not within the 110.Em times.deny 111access lists. 112An empty or non-existent 113.Em times.allow 114list allows access at any 115time, except if a given time is falls within a period in the 116.Em times.deny 117list. 118The format of time period records contained in both 119.Em times.allow 120and 121.Em times.deny 122capability fields is explained in detail in the 123.Xr login_times 3 124manual page. 125.Sh RETURN VALUES 126A non-zero return value from any of these functions indicates that 127login access is granted. 128A zero return value means either that the item being tested is not 129in the 130.Em allow 131access list, or is within the 132.Em deny 133access list. 134.Sh SEE ALSO 135.Xr getcap 3 , 136.Xr login_cap 3 , 137.Xr login_class 3 , 138.Xr login_times 3 , 139.Xr login.conf 5 , 140.Xr termcap 5 141