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
|
/*
Unix SMB/CIFS implementation.
system call wrapper interface.
Copyright (C) Andrew Tridgell 2002
Copyright (C) Andrew Barteltt 2002
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 of the License, 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.
*/
/*
This file may assume linkage with smbd - for things like become_root()
etc.
*/
#include "includes.h"
#ifndef HAVE_GETGROUPLIST
/*
This is a *much* faster way of getting the list of groups for a user
without changing the current supplemenrary group list. The old
method used getgrent() which could take 20 minutes on a really big
network with hundeds of thousands of groups and users. The new method
takes a couple of seconds.
NOTE!! this function only works if it is called as root!
*/
static int getgrouplist_internals(const char *user, gid_t gid, gid_t *groups, int *grpcnt)
{
gid_t *gids_saved;
int ret, ngrp_saved, num_gids;
if (non_root_mode()) {
*grpcnt = 0;
return 0;
}
/* work out how many groups we need to save */
ngrp_saved = getgroups(0, NULL);
if (ngrp_saved == -1) {
/* this shouldn't happen */
return -1;
}
gids_saved = (gid_t *)malloc(sizeof(gid_t) * (ngrp_saved+1));
if (!gids_saved) {
errno = ENOMEM;
return -1;
}
ngrp_saved = getgroups(ngrp_saved, gids_saved);
if (ngrp_saved == -1) {
SAFE_FREE(gids_saved);
/* very strange! */
return -1;
}
if (initgroups(user, gid) != 0) {
DEBUG(0, ("getgrouplist_internals: initgroups() failed!\n"));
SAFE_FREE(gids_saved);
return -1;
}
/* this must be done to cope with systems that put the current egid in the
return from getgroups() */
save_re_gid();
set_effective_gid(gid);
setgid(gid);
num_gids = getgroups(0, NULL);
if (num_gids + 1 > *grpcnt) {
*grpcnt = num_gids + 1;
ret = -1;
} else {
ret = getgroups(*grpcnt - 1, &groups[1]);
if (ret >= 0) {
groups[0] = gid;
*grpcnt = ret + 1;
}
}
restore_re_gid();
if (setgroups(ngrp_saved, gids_saved) != 0) {
/* yikes! */
DEBUG(0,("ERROR: getgrouplist: failed to reset group list!\n"));
smb_panic("getgrouplist: failed to reset group list!\n");
free(gids_saved);
return -1;
}
free(gids_saved);
return ret;
}
#endif
int sys_getgrouplist(const char *user, gid_t gid, gid_t *groups, int *grpcnt)
{
char *p;
int retval;
DEBUG(10,("sys_getgrouplist: user [%s]\n", user));
/* see if we should disable winbindd lookups for local users */
if ( (p = strchr(user, *lp_winbind_separator())) == NULL ) {
if ( !winbind_off() )
DEBUG(0,("sys_getgroup_list: Insufficient environment space for %s\n",
WINBINDD_DONT_ENV));
else
DEBUG(10,("sys_getgrouplist(): disabled winbindd for group lookup [user == %s]\n",
user));
}
#ifdef HAVE_GETGROUPLIST
retval = getgrouplist(user, gid, groups, grpcnt);
#else
become_root();
retval = getgrouplist_internals(user, gid, groups, grpcnt);
unbecome_root();
#endif
/* allow winbindd lookups */
winbind_on();
return retval;
}
|
