nis_groups(3NSL) Networking Services Library Functions nis_groups(3NSL)
NAME
nis_groups, nis_ismember, nis_addmember, nis_removemember, nis_creategroup, nis_destroygroup, nis_verifygroup, nis_print_group_entry - NIS+
group manipulation functions
SYNOPSIS
cc [ flag ... ] file ... -lnsl [ library ... ]
#include <rpcsvc/nis.h>
bool_t nis_ismember(nis_name principal, nis_name group);
nis_error nis_addmember(nis_name member, nis_name group);
nis_error nis_removemember(nis_name member, nis_name group);
nis_error nis_creategroup(nis_name group, uint_t flags);
nis_error nis_destroygroup(nis_name group);
void nis_print_group_entry(nis_name group);
nis_error nis_verifygroup(nis_name group);
DESCRIPTION
These functions manipulate NIS+ groups. They are used by NIS+ clients and servers, and are the interfaces to the group authorization
object.
The names of NIS+ groups are syntactically similar to names of NIS+ objects but they occupy a separate namespace. A group named "a.b.c.d."
is represented by a NIS+ group object named "a.groups_dir.b.c.d."; the functions described here all expect the name of the group, not the
name of the corresponding group object.
There are three types of group members:
o An explicit member is just a NIS+ principal-name, for example "wickedwitch.west.oz."
o An implicit ("domain") member, written "*.west.oz.", means that all principals in the given domain belong to this member. No
other forms of wildcarding are allowed: "wickedwitch.*.oz." is invalid, as is "wickedwitch.west.*.". Note that principals in
subdomains of the given domain are not included.
o A recursive ("group") member, written "@cowards.oz.", refers to another group. All principals that belong to that group are con-
sidered to belong here.
Any member may be made negative by prefixing it with a minus sign ('-'). A group may thus contain explicit, implicit, recursive, negative
explicit, negative implicit, and negative recursive members.
A principal is considered to belong to a group if it belongs to at least one non-negative group member of the group and belongs to no nega-
tive group members.
The nis_ismember() function returns TRUE if it can establish that principal belongs to group; otherwise it returns FALSE.
The nis_addmember() and nis_removemember() functions add or remove a member. They do not check whether the member is valid. The user must
have read and modify rights for the group in question.
The nis_creategroup() and nis_destroygroup() functions create and destroy group objects. The user must have create or destroy rights,
respectively, for the groups_dir directory in the appropriate domain. The parameter flags to nis_creategroup() is currently unused and
should be set to zero.
The nis_print_group_entry() function lists a group's members on the standard output.
The nis_verifygroup() function returns NIS_SUCCESS if the given group exists, otherwise it returns an error code.
These functions only accept fully-qualified NIS+ names.
A group is represented by a NIS+ object with a variant part that is defined in the group_obj structure. See nis_objects(3NSL). It con-
tains the following fields:
uint_t gr_flags; /* Interpretation Flags
(currently unused) */
struct {
uint_t gr_members_len;
nis_name *gr_members_val;
} gr_members; /* Array of members */
NIS+ servers and clients maintain a local cache of expanded groups to enhance their performance when checking for group membership.
Should the membership of a group change, servers and clients with that group cached will not see the change until either the group cache
has expired or it is explicitly flushed. A server's cache may be flushed programmatically by calling the nis_servstate() function with tag
TAG_GCACHE and a value of 1.
There are currently no known methods for nis_ismember(), nis_print_group_entry(), and nis_verifygroup() to get their answers from only the
master server.
EXAMPLES
Example 1 Simple Memberships
Given a group sadsouls.oz. with members tinman.oz., lion.oz., and scarecrow.oz., the function call
bool_var = nis_ismember("lion.oz.", "sadsouls.oz.");
will return 1 (TRUE) and the function call
bool_var = nis_ismember("toto.oz.", "sadsouls.oz.");
will return 0 (FALSE).
Example 2 Implicit Memberships
Given a group baddies.oz., with members wickedwitch.west.oz. and *.monkeys.west.oz., the function call bool_var = nis_ismem-
ber("hogan.monkeys.west.oz.", "baddies.oz."); will return 1 (TRUE) because any principal from the monkeys.west.oz. domain belongs to the
implicit group *.monkeys.west.oz., but the function call
bool_var = nis_ismember("hogan.big.monkeys.west.oz.", "baddies.oz.");
will return 0 (FALSE).
Example 3 Recursive Memberships
Given a group goodandbad.oz., with members toto.kansas, @sadsouls.oz., and @baddies.oz., and the groups sadsouls.oz. and baddies.oz.
defined above, the function call
bool_var = nis_ismember("wickedwitch.west.oz.", "goodandbad.oz.");
will return 1 (TRUE), because wickedwitch.west.oz. is a member of the baddies.oz. group which is recursively included in the goodand-
bad.oz. group.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|MT-Level |MT-Safe |
+-----------------------------+-----------------------------+
SEE ALSO
nisgrpadm(1), nis_objects(3NSL), attributes(5)
NOTES
NIS+ might not be supported in future releases of the Solaris operating system. Tools to aid the migration from NIS+ to LDAP are available
in the current Solaris release. For more information, visit http://www.sun.com/directory/nisplus/transition.html.
SunOS 5.11 10 Nov 2005 nis_groups(3NSL)