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 };
87
88 static const struct nlmsg_perm nlmsg_tcpdiag_perms[] =
89 {
90 { TCPDIAG_GETSOCK, NETLINK_TCPDIAG_SOCKET__NLMSG_READ },
91 { DCCPDIAG_GETSOCK, NETLINK_TCPDIAG_SOCKET__NLMSG_READ },
92 { SOCK_DIAG_BY_FAMILY, NETLINK_TCPDIAG_SOCKET__NLMSG_READ },
93 { SOCK_DESTROY, NETLINK_TCPDIAG_SOCKET__NLMSG_WRITE },
94 };
95
96 static const struct nlmsg_perm nlmsg_xfrm_perms[] =
97 {
98 { XFRM_MSG_NEWSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
99 { XFRM_MSG_DELSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
100 { XFRM_MSG_GETSA, NETLINK_XFRM_SOCKET__NLMSG_READ },
101 { XFRM_MSG_NEWPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
102 { XFRM_MSG_DELPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
103 { XFRM_MSG_GETPOLICY, NETLINK_XFRM_SOCKET__NLMSG_READ },
104 { XFRM_MSG_ALLOCSPI, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
105 { XFRM_MSG_ACQUIRE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
106 { XFRM_MSG_EXPIRE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
107 { XFRM_MSG_UPDPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
108 { XFRM_MSG_UPDSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
109 { XFRM_MSG_POLEXPIRE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
110 { XFRM_MSG_FLUSHSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
111 { XFRM_MSG_FLUSHPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
112 { XFRM_MSG_NEWAE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
113 { XFRM_MSG_GETAE, NETLINK_XFRM_SOCKET__NLMSG_READ },
114 { XFRM_MSG_REPORT, NETLINK_XFRM_SOCKET__NLMSG_READ },
115 { XFRM_MSG_MIGRATE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
116 { XFRM_MSG_NEWSADINFO, NETLINK_XFRM_SOCKET__NLMSG_READ },
117 { XFRM_MSG_GETSADINFO, NETLINK_XFRM_SOCKET__NLMSG_READ },
118 { XFRM_MSG_NEWSPDINFO, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
119 { XFRM_MSG_GETSPDINFO, NETLINK_XFRM_SOCKET__NLMSG_READ },
120 { XFRM_MSG_MAPPING, NETLINK_XFRM_SOCKET__NLMSG_READ },
121 };
122
123 static const struct nlmsg_perm nlmsg_audit_perms[] =
124 {
125 { AUDIT_GET, NETLINK_AUDIT_SOCKET__NLMSG_READ },
126 { AUDIT_SET, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
127 { AUDIT_LIST, NETLINK_AUDIT_SOCKET__NLMSG_READPRIV },
128 { AUDIT_ADD, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
129 { AUDIT_DEL, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
130 { AUDIT_LIST_RULES, NETLINK_AUDIT_SOCKET__NLMSG_READPRIV },
131 { AUDIT_ADD_RULE, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
132 { AUDIT_DEL_RULE, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
133 { AUDIT_USER, NETLINK_AUDIT_SOCKET__NLMSG_RELAY },
134 { AUDIT_SIGNAL_INFO, NETLINK_AUDIT_SOCKET__NLMSG_READ },
135 { AUDIT_TRIM, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
136 { AUDIT_MAKE_EQUIV, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
137 { AUDIT_TTY_GET, NETLINK_AUDIT_SOCKET__NLMSG_READ },
138 { AUDIT_TTY_SET, NETLINK_AUDIT_SOCKET__NLMSG_TTY_AUDIT },
139 { AUDIT_GET_FEATURE, NETLINK_AUDIT_SOCKET__NLMSG_READ },
140 { AUDIT_SET_FEATURE, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
141 };
142
143
nlmsg_perm(u16 nlmsg_type,u32 * perm,const struct nlmsg_perm * tab,size_t tabsize)144 static int nlmsg_perm(u16 nlmsg_type, u32 *perm, const struct nlmsg_perm *tab, size_t tabsize)
145 {
146 int i, err = -EINVAL;
147
148 for (i = 0; i < tabsize/sizeof(struct nlmsg_perm); i++)
149 if (nlmsg_type == tab[i].nlmsg_type) {
150 *perm = tab[i].perm;
151 err = 0;
152 break;
153 }
154
155 return err;
156 }
157
selinux_nlmsg_lookup(u16 sclass,u16 nlmsg_type,u32 * perm)158 int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm)
159 {
160 int err = 0;
161
162 switch (sclass) {
163 case SECCLASS_NETLINK_ROUTE_SOCKET:
164 /* RTM_MAX always points to RTM_SETxxxx, ie RTM_NEWxxx + 3.
165 * If the BUILD_BUG_ON() below fails you must update the
166 * structures at the top of this file with the new mappings
167 * before updating the BUILD_BUG_ON() macro!
168 */
169 BUILD_BUG_ON(RTM_MAX != (RTM_NEWNEXTHOP + 3));
170 err = nlmsg_perm(nlmsg_type, perm, nlmsg_route_perms,
171 sizeof(nlmsg_route_perms));
172 break;
173
174 case SECCLASS_NETLINK_TCPDIAG_SOCKET:
175 err = nlmsg_perm(nlmsg_type, perm, nlmsg_tcpdiag_perms,
176 sizeof(nlmsg_tcpdiag_perms));
177 break;
178
179 case SECCLASS_NETLINK_XFRM_SOCKET:
180 /* If the BUILD_BUG_ON() below fails you must update the
181 * structures at the top of this file with the new mappings
182 * before updating the BUILD_BUG_ON() macro!
183 */
184 BUILD_BUG_ON(XFRM_MSG_MAX != XFRM_MSG_MAPPING);
185 err = nlmsg_perm(nlmsg_type, perm, nlmsg_xfrm_perms,
186 sizeof(nlmsg_xfrm_perms));
187 break;
188
189 case SECCLASS_NETLINK_AUDIT_SOCKET:
190 if ((nlmsg_type >= AUDIT_FIRST_USER_MSG &&
191 nlmsg_type <= AUDIT_LAST_USER_MSG) ||
192 (nlmsg_type >= AUDIT_FIRST_USER_MSG2 &&
193 nlmsg_type <= AUDIT_LAST_USER_MSG2)) {
194 *perm = NETLINK_AUDIT_SOCKET__NLMSG_RELAY;
195 } else {
196 err = nlmsg_perm(nlmsg_type, perm, nlmsg_audit_perms,
197 sizeof(nlmsg_audit_perms));
198 }
199 break;
200
201 /* No messaging from userspace, or class unknown/unhandled */
202 default:
203 err = -ENOENT;
204 break;
205 }
206
207 return err;
208 }
209
nlmsg_set_getlink_perm(u32 perm)210 static void nlmsg_set_getlink_perm(u32 perm)
211 {
212 int i;
213
214 for (i = 0; i < ARRAY_SIZE(nlmsg_route_perms); i++) {
215 if (nlmsg_route_perms[i].nlmsg_type == RTM_GETLINK) {
216 nlmsg_route_perms[i].perm = perm;
217 break;
218 }
219 }
220 }
221
222 /**
223 * Use nlmsg_readpriv as the permission for RTM_GETLINK messages if the
224 * netlink_route_getlink policy capability is set. Otherwise use nlmsg_read.
225 */
selinux_nlmsg_init(void)226 void selinux_nlmsg_init(void)
227 {
228 if (selinux_android_nlroute_getlink())
229 nlmsg_set_getlink_perm(NETLINK_ROUTE_SOCKET__NLMSG_READPRIV);
230 else
231 nlmsg_set_getlink_perm(NETLINK_ROUTE_SOCKET__NLMSG_READ);
232 }
233