xref: /openbmc/linux/security/selinux/nlmsgtab.c (revision 81de3bf3)
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 const 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 };
89 
90 static const struct nlmsg_perm nlmsg_tcpdiag_perms[] =
91 {
92 	{ TCPDIAG_GETSOCK,	NETLINK_TCPDIAG_SOCKET__NLMSG_READ },
93 	{ DCCPDIAG_GETSOCK,	NETLINK_TCPDIAG_SOCKET__NLMSG_READ },
94 	{ SOCK_DIAG_BY_FAMILY,	NETLINK_TCPDIAG_SOCKET__NLMSG_READ },
95 	{ SOCK_DESTROY,		NETLINK_TCPDIAG_SOCKET__NLMSG_WRITE },
96 };
97 
98 static const struct nlmsg_perm nlmsg_xfrm_perms[] =
99 {
100 	{ XFRM_MSG_NEWSA,	NETLINK_XFRM_SOCKET__NLMSG_WRITE },
101 	{ XFRM_MSG_DELSA,	NETLINK_XFRM_SOCKET__NLMSG_WRITE },
102 	{ XFRM_MSG_GETSA,	NETLINK_XFRM_SOCKET__NLMSG_READ  },
103 	{ XFRM_MSG_NEWPOLICY,	NETLINK_XFRM_SOCKET__NLMSG_WRITE },
104 	{ XFRM_MSG_DELPOLICY,	NETLINK_XFRM_SOCKET__NLMSG_WRITE },
105 	{ XFRM_MSG_GETPOLICY,	NETLINK_XFRM_SOCKET__NLMSG_READ  },
106 	{ XFRM_MSG_ALLOCSPI,	NETLINK_XFRM_SOCKET__NLMSG_WRITE },
107 	{ XFRM_MSG_ACQUIRE,	NETLINK_XFRM_SOCKET__NLMSG_WRITE },
108 	{ XFRM_MSG_EXPIRE,	NETLINK_XFRM_SOCKET__NLMSG_WRITE },
109 	{ XFRM_MSG_UPDPOLICY,	NETLINK_XFRM_SOCKET__NLMSG_WRITE },
110 	{ XFRM_MSG_UPDSA,	NETLINK_XFRM_SOCKET__NLMSG_WRITE },
111 	{ XFRM_MSG_POLEXPIRE,	NETLINK_XFRM_SOCKET__NLMSG_WRITE },
112 	{ XFRM_MSG_FLUSHSA,	NETLINK_XFRM_SOCKET__NLMSG_WRITE },
113 	{ XFRM_MSG_FLUSHPOLICY,	NETLINK_XFRM_SOCKET__NLMSG_WRITE },
114 	{ XFRM_MSG_NEWAE,	NETLINK_XFRM_SOCKET__NLMSG_WRITE },
115 	{ XFRM_MSG_GETAE,	NETLINK_XFRM_SOCKET__NLMSG_READ  },
116 	{ XFRM_MSG_REPORT,	NETLINK_XFRM_SOCKET__NLMSG_READ  },
117 	{ XFRM_MSG_MIGRATE,	NETLINK_XFRM_SOCKET__NLMSG_WRITE },
118 	{ XFRM_MSG_NEWSADINFO,	NETLINK_XFRM_SOCKET__NLMSG_READ  },
119 	{ XFRM_MSG_GETSADINFO,	NETLINK_XFRM_SOCKET__NLMSG_READ  },
120 	{ XFRM_MSG_NEWSPDINFO,	NETLINK_XFRM_SOCKET__NLMSG_WRITE },
121 	{ XFRM_MSG_GETSPDINFO,	NETLINK_XFRM_SOCKET__NLMSG_READ  },
122 	{ XFRM_MSG_MAPPING,	NETLINK_XFRM_SOCKET__NLMSG_READ  },
123 };
124 
125 static const struct nlmsg_perm nlmsg_audit_perms[] =
126 {
127 	{ AUDIT_GET,		NETLINK_AUDIT_SOCKET__NLMSG_READ     },
128 	{ AUDIT_SET,		NETLINK_AUDIT_SOCKET__NLMSG_WRITE    },
129 	{ AUDIT_LIST,		NETLINK_AUDIT_SOCKET__NLMSG_READPRIV },
130 	{ AUDIT_ADD,		NETLINK_AUDIT_SOCKET__NLMSG_WRITE    },
131 	{ AUDIT_DEL,		NETLINK_AUDIT_SOCKET__NLMSG_WRITE    },
132 	{ AUDIT_LIST_RULES,	NETLINK_AUDIT_SOCKET__NLMSG_READPRIV },
133 	{ AUDIT_ADD_RULE,	NETLINK_AUDIT_SOCKET__NLMSG_WRITE    },
134 	{ AUDIT_DEL_RULE,	NETLINK_AUDIT_SOCKET__NLMSG_WRITE    },
135 	{ AUDIT_USER,		NETLINK_AUDIT_SOCKET__NLMSG_RELAY    },
136 	{ AUDIT_SIGNAL_INFO,	NETLINK_AUDIT_SOCKET__NLMSG_READ     },
137 	{ AUDIT_TRIM,		NETLINK_AUDIT_SOCKET__NLMSG_WRITE    },
138 	{ AUDIT_MAKE_EQUIV,	NETLINK_AUDIT_SOCKET__NLMSG_WRITE    },
139 	{ AUDIT_TTY_GET,	NETLINK_AUDIT_SOCKET__NLMSG_READ     },
140 	{ AUDIT_TTY_SET,	NETLINK_AUDIT_SOCKET__NLMSG_TTY_AUDIT	},
141 	{ AUDIT_GET_FEATURE,	NETLINK_AUDIT_SOCKET__NLMSG_READ     },
142 	{ AUDIT_SET_FEATURE,	NETLINK_AUDIT_SOCKET__NLMSG_WRITE    },
143 };
144 
145 
146 static int nlmsg_perm(u16 nlmsg_type, u32 *perm, const struct nlmsg_perm *tab, size_t tabsize)
147 {
148 	int i, err = -EINVAL;
149 
150 	for (i = 0; i < tabsize/sizeof(struct nlmsg_perm); i++)
151 		if (nlmsg_type == tab[i].nlmsg_type) {
152 			*perm = tab[i].perm;
153 			err = 0;
154 			break;
155 		}
156 
157 	return err;
158 }
159 
160 int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm)
161 {
162 	int err = 0;
163 
164 	switch (sclass) {
165 	case SECCLASS_NETLINK_ROUTE_SOCKET:
166 		/* RTM_MAX always points to RTM_SETxxxx, ie RTM_NEWxxx + 3.
167 		 * If the BUILD_BUG_ON() below fails you must update the
168 		 * structures at the top of this file with the new mappings
169 		 * before updating the BUILD_BUG_ON() macro!
170 		 */
171 		BUILD_BUG_ON(RTM_MAX != (RTM_NEWLINKPROP + 3));
172 		err = nlmsg_perm(nlmsg_type, perm, nlmsg_route_perms,
173 				 sizeof(nlmsg_route_perms));
174 		break;
175 
176 	case SECCLASS_NETLINK_TCPDIAG_SOCKET:
177 		err = nlmsg_perm(nlmsg_type, perm, nlmsg_tcpdiag_perms,
178 				 sizeof(nlmsg_tcpdiag_perms));
179 		break;
180 
181 	case SECCLASS_NETLINK_XFRM_SOCKET:
182 		/* If the BUILD_BUG_ON() below fails you must update the
183 		 * structures at the top of this file with the new mappings
184 		 * before updating the BUILD_BUG_ON() macro!
185 		 */
186 		BUILD_BUG_ON(XFRM_MSG_MAX != XFRM_MSG_MAPPING);
187 		err = nlmsg_perm(nlmsg_type, perm, nlmsg_xfrm_perms,
188 				 sizeof(nlmsg_xfrm_perms));
189 		break;
190 
191 	case SECCLASS_NETLINK_AUDIT_SOCKET:
192 		if ((nlmsg_type >= AUDIT_FIRST_USER_MSG &&
193 		     nlmsg_type <= AUDIT_LAST_USER_MSG) ||
194 		    (nlmsg_type >= AUDIT_FIRST_USER_MSG2 &&
195 		     nlmsg_type <= AUDIT_LAST_USER_MSG2)) {
196 			*perm = NETLINK_AUDIT_SOCKET__NLMSG_RELAY;
197 		} else {
198 			err = nlmsg_perm(nlmsg_type, perm, nlmsg_audit_perms,
199 					 sizeof(nlmsg_audit_perms));
200 		}
201 		break;
202 
203 	/* No messaging from userspace, or class unknown/unhandled */
204 	default:
205 		err = -ENOENT;
206 		break;
207 	}
208 
209 	return err;
210 }
211