nlmsgtab.c

  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
 23struct nlmsg_perm {
 24	u16 nlmsg_type;
 25	u32 perm;
 26};
 27
 28static const struct nlmsg_perm nlmsg_route_perms[] = {
 29	{ RTM_NEWLINK, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 30	{ RTM_DELLINK, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 31	{ RTM_GETLINK, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 32	{ RTM_SETLINK, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 33	{ RTM_NEWADDR, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 34	{ RTM_DELADDR, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 35	{ RTM_GETADDR, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 36	{ RTM_NEWROUTE, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 37	{ RTM_DELROUTE, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 38	{ RTM_GETROUTE, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 39	{ RTM_NEWNEIGH, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 40	{ RTM_DELNEIGH, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 41	{ RTM_GETNEIGH, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 42	{ RTM_NEWRULE, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 43	{ RTM_DELRULE, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 44	{ RTM_GETRULE, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 45	{ RTM_NEWQDISC, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 46	{ RTM_DELQDISC, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 47	{ RTM_GETQDISC, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 48	{ RTM_NEWTCLASS, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 49	{ RTM_DELTCLASS, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 50	{ RTM_GETTCLASS, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 51	{ RTM_NEWTFILTER, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 52	{ RTM_DELTFILTER, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 53	{ RTM_GETTFILTER, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 54	{ RTM_NEWACTION, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 55	{ RTM_DELACTION, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 56	{ RTM_GETACTION, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 57	{ RTM_NEWPREFIX, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 58	{ RTM_GETMULTICAST, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 59	{ RTM_GETANYCAST, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 60	{ RTM_GETNEIGHTBL, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 61	{ RTM_SETNEIGHTBL, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 62	{ RTM_NEWADDRLABEL, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 63	{ RTM_DELADDRLABEL, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 64	{ RTM_GETADDRLABEL, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 65	{ RTM_GETDCB, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 66	{ RTM_SETDCB, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 67	{ RTM_NEWNETCONF, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 68	{ RTM_DELNETCONF, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 69	{ RTM_GETNETCONF, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 70	{ RTM_NEWMDB, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 71	{ RTM_DELMDB, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 72	{ RTM_GETMDB, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 73	{ RTM_NEWNSID, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 74	{ RTM_DELNSID, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 75	{ RTM_GETNSID, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 76	{ RTM_NEWSTATS, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 77	{ RTM_GETSTATS, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 78	{ RTM_SETSTATS, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 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	{ RTM_NEWNEXTHOPBUCKET, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 92	{ RTM_DELNEXTHOPBUCKET, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 93	{ RTM_GETNEXTHOPBUCKET, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 94	{ RTM_NEWTUNNEL, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 95	{ RTM_DELTUNNEL, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 96	{ RTM_GETTUNNEL, NETLINK_ROUTE_SOCKET__NLMSG_READ },
 97};
 98
 99static const struct nlmsg_perm nlmsg_tcpdiag_perms[] = {
100	{ TCPDIAG_GETSOCK, NETLINK_TCPDIAG_SOCKET__NLMSG_READ },
101	{ SOCK_DIAG_BY_FAMILY, NETLINK_TCPDIAG_SOCKET__NLMSG_READ },
102	{ SOCK_DESTROY, NETLINK_TCPDIAG_SOCKET__NLMSG_WRITE },
103};
104
105static const struct nlmsg_perm nlmsg_xfrm_perms[] = {
106	{ XFRM_MSG_NEWSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
107	{ XFRM_MSG_DELSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
108	{ XFRM_MSG_GETSA, NETLINK_XFRM_SOCKET__NLMSG_READ },
109	{ XFRM_MSG_NEWPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
110	{ XFRM_MSG_DELPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
111	{ XFRM_MSG_GETPOLICY, NETLINK_XFRM_SOCKET__NLMSG_READ },
112	{ XFRM_MSG_ALLOCSPI, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
113	{ XFRM_MSG_ACQUIRE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
114	{ XFRM_MSG_EXPIRE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
115	{ XFRM_MSG_UPDPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
116	{ XFRM_MSG_UPDSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
117	{ XFRM_MSG_POLEXPIRE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
118	{ XFRM_MSG_FLUSHSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
119	{ XFRM_MSG_FLUSHPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
120	{ XFRM_MSG_NEWAE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
121	{ XFRM_MSG_GETAE, NETLINK_XFRM_SOCKET__NLMSG_READ },
122	{ XFRM_MSG_REPORT, NETLINK_XFRM_SOCKET__NLMSG_READ },
123	{ XFRM_MSG_MIGRATE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
124	{ XFRM_MSG_NEWSADINFO, NETLINK_XFRM_SOCKET__NLMSG_READ },
125	{ XFRM_MSG_GETSADINFO, NETLINK_XFRM_SOCKET__NLMSG_READ },
126	{ XFRM_MSG_NEWSPDINFO, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
127	{ XFRM_MSG_GETSPDINFO, NETLINK_XFRM_SOCKET__NLMSG_READ },
128	{ XFRM_MSG_MAPPING, NETLINK_XFRM_SOCKET__NLMSG_READ },
129	{ XFRM_MSG_SETDEFAULT, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
130	{ XFRM_MSG_GETDEFAULT, NETLINK_XFRM_SOCKET__NLMSG_READ },
131};
132
133static const struct nlmsg_perm nlmsg_audit_perms[] = {
134	{ AUDIT_GET, NETLINK_AUDIT_SOCKET__NLMSG_READ },
135	{ AUDIT_SET, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
136	{ AUDIT_LIST, NETLINK_AUDIT_SOCKET__NLMSG_READPRIV },
137	{ AUDIT_ADD, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
138	{ AUDIT_DEL, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
139	{ AUDIT_LIST_RULES, NETLINK_AUDIT_SOCKET__NLMSG_READPRIV },
140	{ AUDIT_ADD_RULE, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
141	{ AUDIT_DEL_RULE, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
142	{ AUDIT_USER, NETLINK_AUDIT_SOCKET__NLMSG_RELAY },
143	{ AUDIT_SIGNAL_INFO, NETLINK_AUDIT_SOCKET__NLMSG_READ },
144	{ AUDIT_TRIM, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
145	{ AUDIT_MAKE_EQUIV, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
146	{ AUDIT_TTY_GET, NETLINK_AUDIT_SOCKET__NLMSG_READ },
147	{ AUDIT_TTY_SET, NETLINK_AUDIT_SOCKET__NLMSG_TTY_AUDIT },
148	{ AUDIT_GET_FEATURE, NETLINK_AUDIT_SOCKET__NLMSG_READ },
149	{ AUDIT_SET_FEATURE, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
150};
151
152static int nlmsg_perm(u16 nlmsg_type, u32 *perm, const struct nlmsg_perm *tab,
153		      size_t tabsize)
154{
155	unsigned int i;
156	int err = -EINVAL;
157
158	for (i = 0; i < tabsize / sizeof(struct nlmsg_perm); i++)
159		if (nlmsg_type == tab[i].nlmsg_type) {
160			*perm = tab[i].perm;
161			err = 0;
162			break;
163		}
164
165	return err;
166}
167
168int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm)
169{
170	/* While it is possible to add a similar permission to other netlink
171	 * classes, note that the extended permission value is matched against
172	 * the nlmsg_type field. Notably, SECCLASS_NETLINK_GENERIC_SOCKET uses
173	 * dynamic values for this field, which means that it cannot be added
174	 * as-is.
175	 */
176
177	switch (sclass) {
178	case SECCLASS_NETLINK_ROUTE_SOCKET:
179		/* RTM_MAX always points to RTM_SETxxxx, ie RTM_NEWxxx + 3.
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(RTM_MAX != (RTM_NEWTUNNEL + 3));
185
186		if (selinux_policycap_netlink_xperm()) {
187			*perm = NETLINK_ROUTE_SOCKET__NLMSG;
188			return 0;
189		}
190		return nlmsg_perm(nlmsg_type, perm, nlmsg_route_perms,
191				  sizeof(nlmsg_route_perms));
192		break;
193	case SECCLASS_NETLINK_TCPDIAG_SOCKET:
194		if (selinux_policycap_netlink_xperm()) {
195			*perm = NETLINK_TCPDIAG_SOCKET__NLMSG;
196			return 0;
197		}
198		return nlmsg_perm(nlmsg_type, perm, nlmsg_tcpdiag_perms,
199				  sizeof(nlmsg_tcpdiag_perms));
200		break;
201	case SECCLASS_NETLINK_XFRM_SOCKET:
202		/* If the BUILD_BUG_ON() below fails you must update the
203		 * structures at the top of this file with the new mappings
204		 * before updating the BUILD_BUG_ON() macro!
205		 */
206		BUILD_BUG_ON(XFRM_MSG_MAX != XFRM_MSG_GETDEFAULT);
207
208		if (selinux_policycap_netlink_xperm()) {
209			*perm = NETLINK_XFRM_SOCKET__NLMSG;
210			return 0;
211		}
212		return nlmsg_perm(nlmsg_type, perm, nlmsg_xfrm_perms,
213				  sizeof(nlmsg_xfrm_perms));
214		break;
215	case SECCLASS_NETLINK_AUDIT_SOCKET:
216		if (selinux_policycap_netlink_xperm()) {
217			*perm = NETLINK_AUDIT_SOCKET__NLMSG;
218			return 0;
219		} else if ((nlmsg_type >= AUDIT_FIRST_USER_MSG &&
220			    nlmsg_type <= AUDIT_LAST_USER_MSG) ||
221			   (nlmsg_type >= AUDIT_FIRST_USER_MSG2 &&
222			    nlmsg_type <= AUDIT_LAST_USER_MSG2)) {
223			*perm = NETLINK_AUDIT_SOCKET__NLMSG_RELAY;
224			return 0;
225		}
226		return nlmsg_perm(nlmsg_type, perm, nlmsg_audit_perms,
227				  sizeof(nlmsg_audit_perms));
228		break;
229	}
230
231	/* No messaging from userspace, or class unknown/unhandled */
232	return -ENOENT;
233}