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40 .Nm cap_grp_limit_cmds ,
41 .Nm cap_grp_limit_fields ,
42 .Nm cap_grp_limit_groups
43 .Nd "library for group database operations in capability mode"
51 .Fn cap_getgrent "cap_channel_t *chan"
53 .Fn cap_getgrnam "cap_channel_t *chan" "const char *name"
55 .Fn cap_getgrgid "cap_channel_t *chan" "gid_t gid"
57 .Fn cap_getgrent_r "cap_channel_t *chan" "struct group *grp" "char *buffer" "size_t bufsize" "struct group **result"
59 .Fn cap_getgrnam_r "cap_channel_t *chan" "const char *name" "struct group *grp" "char *buffer" "size_t bufsize" "struct group **result"
61 .Fn cap_getgrgid_r "cap_channel_t *chan" "gid_t gid" "struct group *grp" "char *buffer" "size_t bufsize" "struct group **result"
63 .Fn cap_setgroupent "cap_channel_t *chan" "int stayopen"
65 .Fn cap_setgrent "cap_channel_t *chan"
67 .Fn cap_endgrent "cap_channel_t *chan"
69 .Fn cap_grp_limit_cmds "cap_channel_t *chan" "const char * const *cmds" "size_t ncmds"
71 .Fn cap_grp_limit_fields "cap_channel_t *chan" "const char * const *fields" "size_t nfields"
73 .Fn cap_grp_limit_groups "cap_channel_t *chan" "const char * const *names" "size_t nnames" "const gid_t *gids" "size_t ngids"
86 are respectively equivalent to
97 except that the connection to the
99 service needs to be provided.
102 .Fn cap_grp_limit_cmds
103 function limits the functions allowed in the service.
106 variable can be set to
117 which will allow to use the function associated with the name.
120 variable contains the number of
125 .Fn cap_grp_limit_fields
126 function allows limit fields returned in the structure
130 variable can be set to
136 The field which was set as the limit will be returned, while the rest of the
137 values not set this way will have default values.
140 variable contains the number of
145 .Fn cap_grp_limit_groups
146 function allows to limit access to groups.
149 variable allows to limit groups by name and the
151 variable by the group number.
156 variables provide numbers of limited names and gids.
158 The following example first opens a capability to casper and then uses this
159 capability to create the
161 casper service and uses it to get a group name.
163 cap_channel_t *capcas, *capgrp;
164 const char *cmds[] = { "getgrgid" };
165 const char *fields[] = { "gr_name" };
166 const gid_t gid[] = { 1 };
169 /* Open capability to Casper. */
172 err(1, "Unable to contact Casper");
174 /* Enter capability mode sandbox. */
175 if (cap_enter() < 0 && errno != ENOSYS)
176 err(1, "Unable to enter capability mode");
178 /* Use Casper capability to create capability to the system.grp service. */
179 capgrp = cap_service_open(capcas, "system.grp");
181 err(1, "Unable to open system.grp service");
183 /* Close Casper capability, we don't need it anymore. */
186 /* Limit service to one single function. */
187 if (cap_grp_limit_cmds(capgrp, cmds, nitems(cmds)))
188 err(1, "Unable to limit access to system.grp service");
190 /* Limit service to one field as we only need name of the group. */
191 if (cap_grp_limit_fields(capgrp, fields, nitems(fields)))
192 err(1, "Unable to limit access to system.grp service");
194 /* Limit service to one gid. */
195 if (cap_grp_limit_groups(capgrp, NULL, 0, gid, nitems(gid)))
196 err(1, "Unable to limit access to system.grp service");
198 group = cap_getgrgid(capgrp, gid[0]);
200 err(1, "Unable to get name of group");
202 printf("GID %d is associated with name %s.\\n", gid[0], group->gr_name);
223 service first appeared in
228 service was implemented by
229 .An Pawel Jakub Dawidek Aq Mt pawel@dawidek.net
230 under sponsorship from the FreeBSD Foundation.
232 This manual page was written by
233 .An Mariusz Zaborski Aq Mt oshogbo@FreeBSD.org .