1 /*
2 * Netlink message type permission tables, for user generated messages.
3 *
4 * Author: James Morris <jmorris@redhat.com>
5 *
6 * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2,
10 * as published by the Free Software Foundation.
11 */
12 #include <linux/types.h>
13 #include <linux/kernel.h>
14 #include <linux/netlink.h>
15 #include <linux/rtnetlink.h>
16 #include <linux/if.h>
17 #include <linux/inet_diag.h>
18 #include <linux/xfrm.h>
19 #include <linux/audit.h>
20 #include <linux/sock_diag.h>
21
22 #include "flask.h"
23 #include "av_permissions.h"
24 #include "security.h"
25
26 struct nlmsg_perm {
27 u16 nlmsg_type;
28 u32 perm;
29 };
30
31 static struct nlmsg_perm nlmsg_route_perms[] =
32 {
33 { RTM_NEWLINK, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
34 { RTM_DELLINK, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
35 { RTM_GETLINK, NETLINK_ROUTE_SOCKET__NLMSG_READ },
36 { RTM_SETLINK, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
37 { RTM_NEWADDR, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
38 { RTM_DELADDR, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
39 { RTM_GETADDR, NETLINK_ROUTE_SOCKET__NLMSG_READ },
40 { RTM_NEWROUTE, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
41 { RTM_DELROUTE, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
42 { RTM_GETROUTE, NETLINK_ROUTE_SOCKET__NLMSG_READ },
43 { RTM_NEWNEIGH, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
44 { RTM_DELNEIGH, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
45 { RTM_GETNEIGH, NETLINK_ROUTE_SOCKET__NLMSG_READ },
46 { RTM_NEWRULE, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
47 { RTM_DELRULE, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
48 { RTM_GETRULE, NETLINK_ROUTE_SOCKET__NLMSG_READ },
49 { RTM_NEWQDISC, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
50 { RTM_DELQDISC, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
51 { RTM_GETQDISC, NETLINK_ROUTE_SOCKET__NLMSG_READ },
52 { RTM_NEWTCLASS, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
53 { RTM_DELTCLASS, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
54 { RTM_GETTCLASS, NETLINK_ROUTE_SOCKET__NLMSG_READ },
55 { RTM_NEWTFILTER, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
56 { RTM_DELTFILTER, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
57 { RTM_GETTFILTER, NETLINK_ROUTE_SOCKET__NLMSG_READ },
58 { RTM_NEWACTION, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
59 { RTM_DELACTION, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
60 { RTM_GETACTION, NETLINK_ROUTE_SOCKET__NLMSG_READ },
61 { RTM_NEWPREFIX, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
62 { RTM_GETMULTICAST, NETLINK_ROUTE_SOCKET__NLMSG_READ },
63 { RTM_GETANYCAST, NETLINK_ROUTE_SOCKET__NLMSG_READ },
64 { RTM_GETNEIGHTBL, NETLINK_ROUTE_SOCKET__NLMSG_READ },
65 { RTM_SETNEIGHTBL, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
66 { RTM_NEWADDRLABEL, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
67 { RTM_DELADDRLABEL, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
68 { RTM_GETADDRLABEL, NETLINK_ROUTE_SOCKET__NLMSG_READ },
69 { RTM_GETDCB, NETLINK_ROUTE_SOCKET__NLMSG_READ },
70 { RTM_SETDCB, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
71 { RTM_NEWNETCONF, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
72 { RTM_DELNETCONF, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
73 { RTM_GETNETCONF, NETLINK_ROUTE_SOCKET__NLMSG_READ },
74 { RTM_NEWMDB, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
75 { RTM_DELMDB, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
76 { RTM_GETMDB, NETLINK_ROUTE_SOCKET__NLMSG_READ },
77 { RTM_NEWNSID, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
78 { RTM_DELNSID, NETLINK_ROUTE_SOCKET__NLMSG_READ },
79 { RTM_GETNSID, NETLINK_ROUTE_SOCKET__NLMSG_READ },
80 { RTM_NEWSTATS, NETLINK_ROUTE_SOCKET__NLMSG_READ },
81 { RTM_GETSTATS, NETLINK_ROUTE_SOCKET__NLMSG_READ },
82 { RTM_NEWCACHEREPORT, NETLINK_ROUTE_SOCKET__NLMSG_READ },
83 };
84
85 static const struct nlmsg_perm nlmsg_tcpdiag_perms[] =
86 {
87 { TCPDIAG_GETSOCK, NETLINK_TCPDIAG_SOCKET__NLMSG_READ },
88 { DCCPDIAG_GETSOCK, NETLINK_TCPDIAG_SOCKET__NLMSG_READ },
89 { SOCK_DIAG_BY_FAMILY, NETLINK_TCPDIAG_SOCKET__NLMSG_READ },
90 { SOCK_DESTROY, NETLINK_TCPDIAG_SOCKET__NLMSG_WRITE },
91 };
92
93 static const struct nlmsg_perm nlmsg_xfrm_perms[] =
94 {
95 { XFRM_MSG_NEWSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
96 { XFRM_MSG_DELSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
97 { XFRM_MSG_GETSA, NETLINK_XFRM_SOCKET__NLMSG_READ },
98 { XFRM_MSG_NEWPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
99 { XFRM_MSG_DELPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
100 { XFRM_MSG_GETPOLICY, NETLINK_XFRM_SOCKET__NLMSG_READ },
101 { XFRM_MSG_ALLOCSPI, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
102 { XFRM_MSG_ACQUIRE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
103 { XFRM_MSG_EXPIRE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
104 { XFRM_MSG_UPDPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
105 { XFRM_MSG_UPDSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
106 { XFRM_MSG_POLEXPIRE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
107 { XFRM_MSG_FLUSHSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
108 { XFRM_MSG_FLUSHPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
109 { XFRM_MSG_NEWAE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
110 { XFRM_MSG_GETAE, NETLINK_XFRM_SOCKET__NLMSG_READ },
111 { XFRM_MSG_REPORT, NETLINK_XFRM_SOCKET__NLMSG_READ },
112 { XFRM_MSG_MIGRATE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
113 { XFRM_MSG_NEWSADINFO, NETLINK_XFRM_SOCKET__NLMSG_READ },
114 { XFRM_MSG_GETSADINFO, NETLINK_XFRM_SOCKET__NLMSG_READ },
115 { XFRM_MSG_NEWSPDINFO, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
116 { XFRM_MSG_GETSPDINFO, NETLINK_XFRM_SOCKET__NLMSG_READ },
117 { XFRM_MSG_MAPPING, NETLINK_XFRM_SOCKET__NLMSG_READ },
118 };
119
120 static const struct nlmsg_perm nlmsg_audit_perms[] =
121 {
122 { AUDIT_GET, NETLINK_AUDIT_SOCKET__NLMSG_READ },
123 { AUDIT_SET, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
124 { AUDIT_LIST, NETLINK_AUDIT_SOCKET__NLMSG_READPRIV },
125 { AUDIT_ADD, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
126 { AUDIT_DEL, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
127 { AUDIT_LIST_RULES, NETLINK_AUDIT_SOCKET__NLMSG_READPRIV },
128 { AUDIT_ADD_RULE, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
129 { AUDIT_DEL_RULE, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
130 { AUDIT_USER, NETLINK_AUDIT_SOCKET__NLMSG_RELAY },
131 { AUDIT_SIGNAL_INFO, NETLINK_AUDIT_SOCKET__NLMSG_READ },
132 { AUDIT_TRIM, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
133 { AUDIT_MAKE_EQUIV, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
134 { AUDIT_TTY_GET, NETLINK_AUDIT_SOCKET__NLMSG_READ },
135 { AUDIT_TTY_SET, NETLINK_AUDIT_SOCKET__NLMSG_TTY_AUDIT },
136 { AUDIT_GET_FEATURE, NETLINK_AUDIT_SOCKET__NLMSG_READ },
137 { AUDIT_SET_FEATURE, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
138 };
139
140
nlmsg_perm(u16 nlmsg_type,u32 * perm,const struct nlmsg_perm * tab,size_t tabsize)141 static int nlmsg_perm(u16 nlmsg_type, u32 *perm, const struct nlmsg_perm *tab, size_t tabsize)
142 {
143 int i, err = -EINVAL;
144
145 for (i = 0; i < tabsize/sizeof(struct nlmsg_perm); i++)
146 if (nlmsg_type == tab[i].nlmsg_type) {
147 *perm = tab[i].perm;
148 err = 0;
149 break;
150 }
151
152 return err;
153 }
154
selinux_nlmsg_lookup(u16 sclass,u16 nlmsg_type,u32 * perm)155 int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm)
156 {
157 int err = 0;
158
159 switch (sclass) {
160 case SECCLASS_NETLINK_ROUTE_SOCKET:
161 /* RTM_MAX always point to RTM_SETxxxx, ie RTM_NEWxxx + 3 */
162 BUILD_BUG_ON(RTM_MAX != (RTM_NEWCACHEREPORT + 3));
163 err = nlmsg_perm(nlmsg_type, perm, nlmsg_route_perms,
164 sizeof(nlmsg_route_perms));
165 break;
166
167 case SECCLASS_NETLINK_TCPDIAG_SOCKET:
168 err = nlmsg_perm(nlmsg_type, perm, nlmsg_tcpdiag_perms,
169 sizeof(nlmsg_tcpdiag_perms));
170 break;
171
172 case SECCLASS_NETLINK_XFRM_SOCKET:
173 BUILD_BUG_ON(XFRM_MSG_MAX != XFRM_MSG_MAPPING);
174 err = nlmsg_perm(nlmsg_type, perm, nlmsg_xfrm_perms,
175 sizeof(nlmsg_xfrm_perms));
176 break;
177
178 case SECCLASS_NETLINK_AUDIT_SOCKET:
179 if ((nlmsg_type >= AUDIT_FIRST_USER_MSG &&
180 nlmsg_type <= AUDIT_LAST_USER_MSG) ||
181 (nlmsg_type >= AUDIT_FIRST_USER_MSG2 &&
182 nlmsg_type <= AUDIT_LAST_USER_MSG2)) {
183 *perm = NETLINK_AUDIT_SOCKET__NLMSG_RELAY;
184 } else {
185 err = nlmsg_perm(nlmsg_type, perm, nlmsg_audit_perms,
186 sizeof(nlmsg_audit_perms));
187 }
188 break;
189
190 /* No messaging from userspace, or class unknown/unhandled */
191 default:
192 err = -ENOENT;
193 break;
194 }
195
196 return err;
197 }
198
nlmsg_set_getlink_perm(u32 perm)199 static void nlmsg_set_getlink_perm(u32 perm)
200 {
201 int i;
202
203 for (i = 0; i < ARRAY_SIZE(nlmsg_route_perms); i++) {
204 if (nlmsg_route_perms[i].nlmsg_type == RTM_GETLINK) {
205 nlmsg_route_perms[i].perm = perm;
206 break;
207 }
208 }
209 }
210
211 /**
212 * Use nlmsg_readpriv as the permission for RTM_GETLINK messages if the
213 * netlink_route_getlink policy capability is set. Otherwise use nlmsg_read.
214 */
selinux_nlmsg_init(void)215 void selinux_nlmsg_init(void)
216 {
217 if (selinux_android_netlink_route)
218 nlmsg_set_getlink_perm(NETLINK_ROUTE_SOCKET__NLMSG_READPRIV);
219 else
220 nlmsg_set_getlink_perm(NETLINK_ROUTE_SOCKET__NLMSG_READ);
221 }
222