/usr/lib/swi-prolog/library/uid.pl is in swi-prolog-nox 7.6.4+dfsg-1build1.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 | /* Part of SWI-Prolog
Author: Jan Wielemaker
E-mail: J.Wielemaker@vu.nl
WWW: http://www.swi-prolog.org
Copyright (c) 2011-2013, VU University Amsterdam
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in
the documentation and/or other materials provided with the
distribution.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
*/
:- module(uid,
[ getuid/1, % -UID
getgid/1, % -GID
geteuid/1, % -UID
getegid/1, % -GID
getgroups/1, % -GIDs
user_info/2, % +User, -UserInfo
group_info/2, % +Group, -GroupInfo
user_data/3, % +Field, +UserInfo, -Value
group_data/3, % +Field, +GroupInfo, -Value
setuid/1, % +UID
setgid/1, % +GID
seteuid/1, % +UID
setegid/1, % +GID
set_user_and_group/1, % +User
set_user_and_group/2 % +User, +Group
]).
:- use_foreign_library(foreign(uid)).
:- if(predicate_property(initgroups(_,_), defined)).
:- export(initgroups/2).
:- else.
initgroups(_,_).
:- endif.
:- if(predicate_property(setgroups(_), defined)).
:- export(setgroups/1).
:- endif.
/** <module> User and group management on Unix systems
This module provides and interface to user and group information on
Posix systems. In addition, it allows for changing user and group ids.
When changing user and group settings for the calling process, bear in
mind that:
- Changing user and groups of the calling process requires permission.
- The functions setgroups() and initgroups() are not part of the
POSIX standard and therefore the derived predicates may not be
present.
@see Please check the documentation of your OS for details on the
semantics of this predicates.
*/
%! getuid(-UID) is det.
%
% UID is the real user ID of the calling process.
%! getgid(-GID) is det.
%
% GID is the real group ID of the calling process.
%! geteuid(-UID) is det.
%
% UID is the effective user ID of the calling process.
%! getegid(-GID) is det.
%
% GID is the effective group ID of the calling process.
%! getgroups(-GroupsIDs:list(integer)) is det.
%
% GroupsIDs is the set of supplementary group IDs of the calling
% process. Note that these are numeric identifiers. Use
% group_info/2 to obtain details on the returned group
% identifiers.
%! user_info(+User, -UserData) is det.
%
% UserData represent the passwd information for User. User is
% either a numeric UID or a user name. The predicate user_data/3
% can be used to extract information from UserData.
%! user_data(?Field, ?UserData, ?Value)
%
% Value is the value for Field in UserData. Defined fields are:
%
% * name
% Name of the user
% * password
% Password hash of the user (or =x= if this is not accessible)
% * uid
% Numeric user id of the user
% * gid
% Numeric primary group id of the user
% * comment
% The _gecos_ field
% * home
% Home directory of the user
% * shell
% Default (login) shell of the user.
user_data(name, user_info(Nam, _, _, _, _, _, _), Nam).
user_data(password, user_info(_, PWD, _, _, _, _, _), PWD).
user_data(uid, user_info(_, _, UID, _, _, _, _), UID).
user_data(gid, user_info(_, _, _, GID, _, _, _), GID).
user_data(comment, user_info(_, _, _, _, GEC, _, _), GEC).
user_data(home, user_info(_, _, _, _, _, HOM, _), HOM).
user_data(shell, user_info(_, _, _, _, _, _, SHE), SHE).
%! group_info(+Group, -GroupData) is det.
%
% GroupData represent the group information for Group. Group is
% either a numeric GID or a group name. The predicate group_data/3
% can be used to extract information from GroupData.
%! group_data(?Field, ?GroupData, ?Value)
%
% Value is the value for Field GroupData. Defined fields are:
%
% * name
% Name of the user
% * password
% Password hash of the user (or =x= if this is not accessible)
% * gid
% Numeric group id of the group
% * members
% List of user-names that are member of this group.
group_data(name, group_info(Nam, _, _, _), Nam).
group_data(password, group_info(_, PWD, _, _), PWD).
group_data(gid, group_info(_, _, GID, _), GID).
group_data(members, group_info(_, _, _, MBR), MBR).
/*******************************
* SETTING *
*******************************/
%! setuid(+UID)
%
% Set the user id of the calling process.
%! seteuid(+UID)
%
% Set the effective user id of the calling process.
%! setgid(+GID)
%
% Set the group id of the calling process.
%! setegid(+GID)
%
% Set the effective group id of the calling process.
%! initgroups(+User, +Group) is det.
%
% Initialise the group access list of the calling process to the
% registered groups for User and the group Group. This predicate
% is only available if the underlying OS provides it.
%! setgroups(+Groups:list(integer)) is det.
%
% Set the group access list of the caling process to the indicated
% groups. This predicate is only available if the underlying OS
% provides it.
%! set_user_and_group(+User) is det.
%! set_user_and_group(+User, +Group) is det.
%
% Set the UID and GID to the User. User is either a UID or a user
% name. If Group is not specified, the primary group of User is
% used. If initgroups/2 is available, the resulting group access
% list of the calling process consists of the registered groups
% for User and the specified Group.
set_user_and_group(User) :-
user_info(User, Data),
user_data(uid, Data, UID),
user_data(gid, Data, GID),
initgroups(User, GID),
setgid(GID),
setuid(UID).
set_user_and_group(User, Group) :-
user_info(User, Data),
group_info(Group, GData),
user_data(uid, Data, UID),
user_data(gid, Data, UGID),
group_data(gid, GData, GID),
initgroups(User, UGID),
setgid(GID),
setuid(UID).
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