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
|
/*-
* Copyright (c) 1999-2002 Robert N. M. Watson
* Copyright (c) 2001-2002 Networks Associates Technology, Inc.
* All rights reserved.
*
* This software was developed by Robert Watson for the TrustedBSD Project.
*
* This software was developed for the FreeBSD Project in part by Network
* Associates Laboratories, the Security Research Division of Network
* Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"),
* as part of the DARPA CHATS research program.
*
* 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 AUTHOR 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 AUTHOR 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.
*
* $FreeBSD$
*/
/*
* Developed by the TrustedBSD Project.
* Prevent processes owned by a particular uid from seeing various transient
* kernel objects associated with other uids.
*/
#include <sys/types.h>
#include <sys/param.h>
#include <sys/conf.h>
#include <sys/kernel.h>
#include <sys/mac.h>
#include <sys/mount.h>
#include <sys/proc.h>
#include <sys/systm.h>
#include <sys/sysproto.h>
#include <sys/sysent.h>
#include <sys/vnode.h>
#include <sys/file.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sysctl.h>
#include <net/bpfdesc.h>
#include <net/if.h>
#include <net/if_types.h>
#include <net/if_var.h>
#include <vm/vm.h>
#include <sys/mac_policy.h>
SYSCTL_DECL(_security_mac);
SYSCTL_NODE(_security_mac, OID_AUTO, seeotheruids, CTLFLAG_RW, 0,
"TrustedBSD mac_seeotheruids policy controls");
static int mac_seeotheruids_enabled = 1;
SYSCTL_INT(_security_mac_seeotheruids, OID_AUTO, enabled, CTLFLAG_RW,
&mac_seeotheruids_enabled, 0, "Enforce seeotheruids policy");
/*
* Exception: allow credentials to be aware of other credentials with the
* same primary gid.
*/
static int primarygroup_enabled = 0;
SYSCTL_INT(_security_mac_seeotheruids, OID_AUTO, primarygroup_enabled,
CTLFLAG_RW, &primarygroup_enabled, 0, "Make an exception for credentials "
"with the same real primary group id");
/*
* Exception: allow processes with a specific gid to be exempt from the
* policy. One sysctl enables this functionality; the other sets the
* exempt gid.
*/
static int specificgid_enabled = 0;
SYSCTL_INT(_security_mac_seeotheruids, OID_AUTO, specificgid_enabled,
CTLFLAG_RW, &specificgid_enabled, 0, "Make an exception for credentials "
"with a specific gid as their real primary group id or group set");
static gid_t specificgid = 0;
SYSCTL_INT(_security_mac_seeotheruids, OID_AUTO, specificgid, CTLFLAG_RW,
&specificgid, 0, "Specific gid to be exempt from seeotheruids policy");
static int
mac_seeotheruids_check(struct ucred *u1, struct ucred *u2)
{
if (!mac_seeotheruids_enabled)
return (0);
if (primarygroup_enabled) {
if (u1->cr_rgid == u2->cr_rgid)
return (0);
}
if (specificgid_enabled) {
if (u1->cr_rgid == specificgid || groupmember(specificgid, u1))
return (0);
}
if (u1->cr_ruid == u2->cr_ruid)
return (0);
return (ESRCH);
}
static int
mac_seeotheruids_check_cred_visible(struct ucred *u1, struct ucred *u2)
{
return (mac_seeotheruids_check(u1, u2));
}
static int
mac_seeotheruids_check_proc_signal(struct ucred *cred, struct proc *proc,
int signum)
{
return (mac_seeotheruids_check(cred, proc->p_ucred));
}
static int
mac_seeotheruids_check_proc_sched(struct ucred *cred, struct proc *proc)
{
return (mac_seeotheruids_check(cred, proc->p_ucred));
}
static int
mac_seeotheruids_check_proc_debug(struct ucred *cred, struct proc *proc)
{
return (mac_seeotheruids_check(cred, proc->p_ucred));
}
static int
mac_seeotheruids_check_socket_visible(struct ucred *cred, struct socket *socket,
struct label *socketlabel)
{
return (mac_seeotheruids_check(cred, socket->so_cred));
}
static struct mac_policy_ops mac_seeotheruids_ops =
{
.mpo_check_cred_visible = mac_seeotheruids_check_cred_visible,
.mpo_check_proc_debug = mac_seeotheruids_check_proc_debug,
.mpo_check_proc_sched = mac_seeotheruids_check_proc_sched,
.mpo_check_proc_signal = mac_seeotheruids_check_proc_signal,
.mpo_check_socket_visible = mac_seeotheruids_check_socket_visible,
};
MAC_POLICY_SET(&mac_seeotheruids_ops, mac_seeotheruids,
"TrustedBSD MAC/seeotheruids", MPC_LOADTIME_FLAG_UNLOADOK, NULL);
|
