1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Netlink message type permission tables, for user generated messages.
4 *
5 * Author: James Morris <jmorris@redhat.com>
6 *
7 * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
8 */
9 #include <linux/types.h>
10 #include <linux/kernel.h>
11 #include <linux/netlink.h>
12 #include <linux/rtnetlink.h>
13 #include <linux/if.h>
14 #include <linux/inet_diag.h>
15 #include <linux/xfrm.h>
16 #include <linux/audit.h>
17 #include <linux/sock_diag.h>
18
19 #include "flask.h"
20 #include "av_permissions.h"
21 #include "security.h"
22
23 struct nlmsg_perm {
24 u16 nlmsg_type;
25 u32 perm;
26 };
27
28 static struct nlmsg_perm nlmsg_route_perms[] =
29 {
30 { RTM_NEWLINK, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
31 { RTM_DELLINK, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
32 { RTM_GETLINK, NETLINK_ROUTE_SOCKET__NLMSG_READ },
33 { RTM_SETLINK, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
34 { RTM_NEWADDR, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
35 { RTM_DELADDR, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
36 { RTM_GETADDR, NETLINK_ROUTE_SOCKET__NLMSG_READ },
37 { RTM_NEWROUTE, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
38 { RTM_DELROUTE, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
39 { RTM_GETROUTE, NETLINK_ROUTE_SOCKET__NLMSG_READ },
40 { RTM_NEWNEIGH, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
41 { RTM_DELNEIGH, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
42 { RTM_GETNEIGH, NETLINK_ROUTE_SOCKET__NLMSG_READ },
43 { RTM_NEWRULE, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
44 { RTM_DELRULE, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
45 { RTM_GETRULE, NETLINK_ROUTE_SOCKET__NLMSG_READ },
46 { RTM_NEWQDISC, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
47 { RTM_DELQDISC, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
48 { RTM_GETQDISC, NETLINK_ROUTE_SOCKET__NLMSG_READ },
49 { RTM_NEWTCLASS, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
50 { RTM_DELTCLASS, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
51 { RTM_GETTCLASS, NETLINK_ROUTE_SOCKET__NLMSG_READ },
52 { RTM_NEWTFILTER, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
53 { RTM_DELTFILTER, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
54 { RTM_GETTFILTER, NETLINK_ROUTE_SOCKET__NLMSG_READ },
55 { RTM_NEWACTION, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
56 { RTM_DELACTION, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
57 { RTM_GETACTION, NETLINK_ROUTE_SOCKET__NLMSG_READ },
58 { RTM_NEWPREFIX, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
59 { RTM_GETMULTICAST, NETLINK_ROUTE_SOCKET__NLMSG_READ },
60 { RTM_GETANYCAST, NETLINK_ROUTE_SOCKET__NLMSG_READ },
61 { RTM_GETNEIGHTBL, NETLINK_ROUTE_SOCKET__NLMSG_READ },
62 { RTM_SETNEIGHTBL, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
63 { RTM_NEWADDRLABEL, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
64 { RTM_DELADDRLABEL, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
65 { RTM_GETADDRLABEL, NETLINK_ROUTE_SOCKET__NLMSG_READ },
66 { RTM_GETDCB, NETLINK_ROUTE_SOCKET__NLMSG_READ },
67 { RTM_SETDCB, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
68 { RTM_NEWNETCONF, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
69 { RTM_DELNETCONF, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
70 { RTM_GETNETCONF, NETLINK_ROUTE_SOCKET__NLMSG_READ },
71 { RTM_NEWMDB, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
72 { RTM_DELMDB, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
73 { RTM_GETMDB, NETLINK_ROUTE_SOCKET__NLMSG_READ },
74 { RTM_NEWNSID, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
75 { RTM_DELNSID, NETLINK_ROUTE_SOCKET__NLMSG_READ },
76 { RTM_GETNSID, NETLINK_ROUTE_SOCKET__NLMSG_READ },
77 { RTM_NEWSTATS, NETLINK_ROUTE_SOCKET__NLMSG_READ },
78 { RTM_GETSTATS, NETLINK_ROUTE_SOCKET__NLMSG_READ },
79 { RTM_NEWCACHEREPORT, NETLINK_ROUTE_SOCKET__NLMSG_READ },
80 { RTM_NEWCHAIN, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
81 { RTM_DELCHAIN, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
82 { RTM_GETCHAIN, NETLINK_ROUTE_SOCKET__NLMSG_READ },
83 { RTM_NEWNEXTHOP, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
84 { RTM_DELNEXTHOP, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
85 { RTM_GETNEXTHOP, NETLINK_ROUTE_SOCKET__NLMSG_READ },
86 { RTM_NEWLINKPROP, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
87 { RTM_DELLINKPROP, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
88 { RTM_NEWVLAN, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
89 { RTM_DELVLAN, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
90 { RTM_GETVLAN, NETLINK_ROUTE_SOCKET__NLMSG_READ },
91 };
92
93 static const struct nlmsg_perm nlmsg_tcpdiag_perms[] =
94 {
95 { TCPDIAG_GETSOCK, NETLINK_TCPDIAG_SOCKET__NLMSG_READ },
96 { DCCPDIAG_GETSOCK, NETLINK_TCPDIAG_SOCKET__NLMSG_READ },
97 { SOCK_DIAG_BY_FAMILY, NETLINK_TCPDIAG_SOCKET__NLMSG_READ },
98 { SOCK_DESTROY, NETLINK_TCPDIAG_SOCKET__NLMSG_WRITE },
99 };
100
101 static const struct nlmsg_perm nlmsg_xfrm_perms[] =
102 {
103 { XFRM_MSG_NEWSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
104 { XFRM_MSG_DELSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
105 { XFRM_MSG_GETSA, NETLINK_XFRM_SOCKET__NLMSG_READ },
106 { XFRM_MSG_NEWPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
107 { XFRM_MSG_DELPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
108 { XFRM_MSG_GETPOLICY, NETLINK_XFRM_SOCKET__NLMSG_READ },
109 { XFRM_MSG_ALLOCSPI, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
110 { XFRM_MSG_ACQUIRE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
111 { XFRM_MSG_EXPIRE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
112 { XFRM_MSG_UPDPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
113 { XFRM_MSG_UPDSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
114 { XFRM_MSG_POLEXPIRE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
115 { XFRM_MSG_FLUSHSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
116 { XFRM_MSG_FLUSHPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
117 { XFRM_MSG_NEWAE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
118 { XFRM_MSG_GETAE, NETLINK_XFRM_SOCKET__NLMSG_READ },
119 { XFRM_MSG_REPORT, NETLINK_XFRM_SOCKET__NLMSG_READ },
120 { XFRM_MSG_MIGRATE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
121 { XFRM_MSG_NEWSADINFO, NETLINK_XFRM_SOCKET__NLMSG_READ },
122 { XFRM_MSG_GETSADINFO, NETLINK_XFRM_SOCKET__NLMSG_READ },
123 { XFRM_MSG_NEWSPDINFO, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
124 { XFRM_MSG_GETSPDINFO, NETLINK_XFRM_SOCKET__NLMSG_READ },
125 { XFRM_MSG_MAPPING, NETLINK_XFRM_SOCKET__NLMSG_READ },
126 };
127
128 static const struct nlmsg_perm nlmsg_audit_perms[] =
129 {
130 { AUDIT_GET, NETLINK_AUDIT_SOCKET__NLMSG_READ },
131 { AUDIT_SET, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
132 { AUDIT_LIST, NETLINK_AUDIT_SOCKET__NLMSG_READPRIV },
133 { AUDIT_ADD, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
134 { AUDIT_DEL, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
135 { AUDIT_LIST_RULES, NETLINK_AUDIT_SOCKET__NLMSG_READPRIV },
136 { AUDIT_ADD_RULE, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
137 { AUDIT_DEL_RULE, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
138 { AUDIT_USER, NETLINK_AUDIT_SOCKET__NLMSG_RELAY },
139 { AUDIT_SIGNAL_INFO, NETLINK_AUDIT_SOCKET__NLMSG_READ },
140 { AUDIT_TRIM, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
141 { AUDIT_MAKE_EQUIV, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
142 { AUDIT_TTY_GET, NETLINK_AUDIT_SOCKET__NLMSG_READ },
143 { AUDIT_TTY_SET, NETLINK_AUDIT_SOCKET__NLMSG_TTY_AUDIT },
144 { AUDIT_GET_FEATURE, NETLINK_AUDIT_SOCKET__NLMSG_READ },
145 { AUDIT_SET_FEATURE, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
146 };
147
148
nlmsg_perm(u16 nlmsg_type,u32 * perm,const struct nlmsg_perm * tab,size_t tabsize)149 static int nlmsg_perm(u16 nlmsg_type, u32 *perm, const struct nlmsg_perm *tab, size_t tabsize)
150 {
151 int i, err = -EINVAL;
152
153 for (i = 0; i < tabsize/sizeof(struct nlmsg_perm); i++)
154 if (nlmsg_type == tab[i].nlmsg_type) {
155 *perm = tab[i].perm;
156 err = 0;
157 break;
158 }
159
160 return err;
161 }
162
selinux_nlmsg_lookup(u16 sclass,u16 nlmsg_type,u32 * perm)163 int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm)
164 {
165 int err = 0;
166
167 switch (sclass) {
168 case SECCLASS_NETLINK_ROUTE_SOCKET:
169 /* RTM_MAX always points to RTM_SETxxxx, ie RTM_NEWxxx + 3.
170 * If the BUILD_BUG_ON() below fails you must update the
171 * structures at the top of this file with the new mappings
172 * before updating the BUILD_BUG_ON() macro!
173 */
174 BUILD_BUG_ON(RTM_MAX != (RTM_NEWVLAN + 3));
175 err = nlmsg_perm(nlmsg_type, perm, nlmsg_route_perms,
176 sizeof(nlmsg_route_perms));
177 break;
178
179 case SECCLASS_NETLINK_TCPDIAG_SOCKET:
180 err = nlmsg_perm(nlmsg_type, perm, nlmsg_tcpdiag_perms,
181 sizeof(nlmsg_tcpdiag_perms));
182 break;
183
184 case SECCLASS_NETLINK_XFRM_SOCKET:
185 /* If the BUILD_BUG_ON() below fails you must update the
186 * structures at the top of this file with the new mappings
187 * before updating the BUILD_BUG_ON() macro!
188 */
189 BUILD_BUG_ON(XFRM_MSG_MAX != XFRM_MSG_MAPPING);
190 err = nlmsg_perm(nlmsg_type, perm, nlmsg_xfrm_perms,
191 sizeof(nlmsg_xfrm_perms));
192 break;
193
194 case SECCLASS_NETLINK_AUDIT_SOCKET:
195 if ((nlmsg_type >= AUDIT_FIRST_USER_MSG &&
196 nlmsg_type <= AUDIT_LAST_USER_MSG) ||
197 (nlmsg_type >= AUDIT_FIRST_USER_MSG2 &&
198 nlmsg_type <= AUDIT_LAST_USER_MSG2)) {
199 *perm = NETLINK_AUDIT_SOCKET__NLMSG_RELAY;
200 } else {
201 err = nlmsg_perm(nlmsg_type, perm, nlmsg_audit_perms,
202 sizeof(nlmsg_audit_perms));
203 }
204 break;
205
206 /* No messaging from userspace, or class unknown/unhandled */
207 default:
208 err = -ENOENT;
209 break;
210 }
211
212 return err;
213 }
214
nlmsg_set_perm_for_type(u32 perm,u16 type)215 static void nlmsg_set_perm_for_type(u32 perm, u16 type)
216 {
217 int i;
218
219 for (i = 0; i < ARRAY_SIZE(nlmsg_route_perms); i++) {
220 if (nlmsg_route_perms[i].nlmsg_type == type) {
221 nlmsg_route_perms[i].perm = perm;
222 break;
223 }
224 }
225 }
226
227 /**
228 * Use nlmsg_readpriv as the permission for RTM_GETLINK messages if the
229 * netlink_route_getlink policy capability is set. Otherwise use nlmsg_read.
230 * Similarly, use nlmsg_getneigh for RTM_GETNEIGH and RTM_GETNEIGHTBL if the
231 * netlink_route_getneigh policy capability is set. Otherwise use nlmsg_read.
232 */
selinux_nlmsg_init(void)233 void selinux_nlmsg_init(void)
234 {
235 if (selinux_android_nlroute_getlink())
236 nlmsg_set_perm_for_type(NETLINK_ROUTE_SOCKET__NLMSG_READPRIV,
237 RTM_GETLINK);
238 else
239 nlmsg_set_perm_for_type(NETLINK_ROUTE_SOCKET__NLMSG_READ,
240 RTM_GETLINK);
241
242 if (selinux_android_nlroute_getneigh()) {
243 nlmsg_set_perm_for_type(NETLINK_ROUTE_SOCKET__NLMSG_GETNEIGH,
244 RTM_GETNEIGH);
245 nlmsg_set_perm_for_type(NETLINK_ROUTE_SOCKET__NLMSG_GETNEIGH,
246 RTM_GETNEIGHTBL);
247 } else {
248 nlmsg_set_perm_for_type(NETLINK_ROUTE_SOCKET__NLMSG_READ,
249 RTM_GETNEIGH);
250 nlmsg_set_perm_for_type(NETLINK_ROUTE_SOCKET__NLMSG_READ,
251 RTM_GETNEIGHTBL);
252 }
253 }
254