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
|
/* Set posix-compatible ugids
Copyright (C) 1997 Free Software Foundation, Inc.
Written by Miles Bader <miles@gnu.ai.mit.edu>
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2, or (at
your option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
#include <stdlib.h>
#include "ugids.h"
/* Install UID into UGIDS as the main user, making sure that the posix
`real' and `saved' uid slots are filled in, and similarly add all
groups to which UID belongs. */
error_t
ugids_set_posix_user (struct ugids *ugids, uid_t uid)
{
error_t err;
struct idvec imp_gids = IDVEC_INIT;
uid_t uids_ids[] = { uid };
struct idvec uids = { uids_ids, 1 };
error_t update_real (struct idvec *avail_ids, uid_t id)
{
if (avail_ids->num == 0
|| !idvec_tail_contains (avail_ids, 1, avail_ids->ids[0]))
return idvec_insert (avail_ids, 0, id);
else
avail_ids->ids[0] = id;
return 0;
}
idvec_merge_implied_gids (&imp_gids, &uids);
/* Try to add UID. */
err = idvec_insert_only (&ugids->eff_uids, 0, uid); /* Effective */
if (! err)
err = update_real (&ugids->avail_uids, uid); /* Real */
if (! err)
err = idvec_insert_only (&ugids->avail_uids, 1, uid); /* Saved */
if (!err && imp_gids.num > 0)
/* Now do the gids. */
{
/* The main gid associated with UID (usually from /etc/passwd). */
gid_t gid = imp_gids.ids[0];
/* True if GID was already an available gid. */
int gid_was_avail = idvec_contains (&ugids->avail_gids, gid);
/* Update the implied sets for the gids: they're implied unless
they were present as non-implied gids before. Here we
remove existing effective gids from the IMP_GIDS before we
added it to the implied sets -- if some of those gids were
actually implied, they'll already be present in the implied
set. */
idvec_subtract (&imp_gids, &ugids->eff_gids);
/* Now add GID, as effective, real, and saved gids. */
if (! err) /* Effective */
err = idvec_insert_only (&ugids->eff_gids, 0, gid);
if (! err) /* Real */
err = update_real (&ugids->avail_gids, gid);
if (! err) /* Saved */
err = idvec_insert_only (&ugids->avail_gids, 1, gid);
/* Mark GID as implied in the available gids unless it was already
present (in which case its implied status is already settled). */
if (!err && !gid_was_avail)
err = idvec_add (&ugids->imp_avail_gids, gid);
/* Add the other implied gids to the end of the effective gids. */
if (! err)
err = idvec_merge (&ugids->eff_gids, &imp_gids);
/* And make them implied. */
if (! err)
err = idvec_merge (&ugids->imp_eff_gids, &imp_gids);
}
idvec_fini (&imp_gids);
return err;
}
|
