security/selinux/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 <[email protected]>
   6  *
   7  * Copyright (C) 2004 Red Hat, Inc., James Morris <[email protected]>
   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         { 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
  99 static const struct nlmsg_perm nlmsg_tcpdiag_perms[] = {
 100         { TCPDIAG_GETSOCK, NETLINK_TCPDIAG_SOCKET__NLMSG_READ },
 101         { DCCPDIAG_GETSOCK, NETLINK_TCPDIAG_SOCKET__NLMSG_READ },
 102         { SOCK_DIAG_BY_FAMILY, NETLINK_TCPDIAG_SOCKET__NLMSG_READ },
 103         { SOCK_DESTROY, NETLINK_TCPDIAG_SOCKET__NLMSG_WRITE },
 104 };
 105
 106 static const struct nlmsg_perm nlmsg_xfrm_perms[] = {
 107         { XFRM_MSG_NEWSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
 108         { XFRM_MSG_DELSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
 109         { XFRM_MSG_GETSA, NETLINK_XFRM_SOCKET__NLMSG_READ },
 110         { XFRM_MSG_NEWPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
 111         { XFRM_MSG_DELPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
 112         { XFRM_MSG_GETPOLICY, NETLINK_XFRM_SOCKET__NLMSG_READ },
 113         { XFRM_MSG_ALLOCSPI, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
 114         { XFRM_MSG_ACQUIRE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
 115         { XFRM_MSG_EXPIRE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
 116         { XFRM_MSG_UPDPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
 117         { XFRM_MSG_UPDSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
 118         { XFRM_MSG_POLEXPIRE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
 119         { XFRM_MSG_FLUSHSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
 120         { XFRM_MSG_FLUSHPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
 121         { XFRM_MSG_NEWAE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
 122         { XFRM_MSG_GETAE, NETLINK_XFRM_SOCKET__NLMSG_READ },
 123         { XFRM_MSG_REPORT, NETLINK_XFRM_SOCKET__NLMSG_READ },
 124         { XFRM_MSG_MIGRATE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
 125         { XFRM_MSG_NEWSADINFO, NETLINK_XFRM_SOCKET__NLMSG_READ },
 126         { XFRM_MSG_GETSADINFO, NETLINK_XFRM_SOCKET__NLMSG_READ },
 127         { XFRM_MSG_NEWSPDINFO, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
 128         { XFRM_MSG_GETSPDINFO, NETLINK_XFRM_SOCKET__NLMSG_READ },
 129         { XFRM_MSG_MAPPING, NETLINK_XFRM_SOCKET__NLMSG_READ },
 130         { XFRM_MSG_SETDEFAULT, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
 131         { XFRM_MSG_GETDEFAULT, NETLINK_XFRM_SOCKET__NLMSG_READ },
 132 };
 133
 134 static const struct nlmsg_perm nlmsg_audit_perms[] = {
 135         { AUDIT_GET, NETLINK_AUDIT_SOCKET__NLMSG_READ },
 136         { AUDIT_SET, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
 137         { AUDIT_LIST, NETLINK_AUDIT_SOCKET__NLMSG_READPRIV },
 138         { AUDIT_ADD, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
 139         { AUDIT_DEL, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
 140         { AUDIT_LIST_RULES, NETLINK_AUDIT_SOCKET__NLMSG_READPRIV },
 141         { AUDIT_ADD_RULE, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
 142         { AUDIT_DEL_RULE, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
 143         { AUDIT_USER, NETLINK_AUDIT_SOCKET__NLMSG_RELAY },
 144         { AUDIT_SIGNAL_INFO, NETLINK_AUDIT_SOCKET__NLMSG_READ },
 145         { AUDIT_TRIM, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
 146         { AUDIT_MAKE_EQUIV, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
 147         { AUDIT_TTY_GET, NETLINK_AUDIT_SOCKET__NLMSG_READ },
 148         { AUDIT_TTY_SET, NETLINK_AUDIT_SOCKET__NLMSG_TTY_AUDIT },
 149         { AUDIT_GET_FEATURE, NETLINK_AUDIT_SOCKET__NLMSG_READ },
 150         { AUDIT_SET_FEATURE, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
 151 };
 152
 153 static int nlmsg_perm(u16 nlmsg_type, u32 *perm, const struct nlmsg_perm *tab,
 154                       size_t tabsize)
 155 {
 156         unsigned int i;
 157         int err = -EINVAL;
 158
 159         for (i = 0; i < tabsize / sizeof(struct nlmsg_perm); i++)
 160                 if (nlmsg_type == tab[i].nlmsg_type) {
 161                         *perm = tab[i].perm;
 162                         err = 0;
 163                         break;
 164                 }
 165
 166         return err;
 167 }
 168
 169 int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm)
 170 {
 171         /* While it is possible to add a similar permission to other netlink
 172          * classes, note that the extended permission value is matched against
 173          * the nlmsg_type field. Notably, SECCLASS_NETLINK_GENERIC_SOCKET uses
 174          * dynamic values for this field, which means that it cannot be added
 175          * as-is.
 176          */
 177
 178         switch (sclass) {
 179         case SECCLASS_NETLINK_ROUTE_SOCKET:
 180                 /* RTM_MAX always points to RTM_SETxxxx, ie RTM_NEWxxx + 3.
 181                  * If the BUILD_BUG_ON() below fails you must update the
 182                  * structures at the top of this file with the new mappings
 183                  * before updating the BUILD_BUG_ON() macro!
 184                  */
 185                 BUILD_BUG_ON(RTM_MAX != (RTM_NEWTUNNEL + 3));
 186
 187                 if (selinux_policycap_netlink_xperm()) {
 188                         *perm = NETLINK_ROUTE_SOCKET__NLMSG;
 189                         return 0;
 190                 }
 191                 return nlmsg_perm(nlmsg_type, perm, nlmsg_route_perms,
 192                                   sizeof(nlmsg_route_perms));
 193                 break;
 194         case SECCLASS_NETLINK_TCPDIAG_SOCKET:
 195                 if (selinux_policycap_netlink_xperm()) {
 196                         *perm = NETLINK_TCPDIAG_SOCKET__NLMSG;
 197                         return 0;
 198                 }
 199                 return nlmsg_perm(nlmsg_type, perm, nlmsg_tcpdiag_perms,
 200                                   sizeof(nlmsg_tcpdiag_perms));
 201                 break;
 202         case SECCLASS_NETLINK_XFRM_SOCKET:
 203                 /* If the BUILD_BUG_ON() below fails you must update the
 204                  * structures at the top of this file with the new mappings
 205                  * before updating the BUILD_BUG_ON() macro!
 206                  */
 207                 BUILD_BUG_ON(XFRM_MSG_MAX != XFRM_MSG_GETDEFAULT);
 208
 209                 if (selinux_policycap_netlink_xperm()) {
 210                         *perm = NETLINK_XFRM_SOCKET__NLMSG;
 211                         return 0;
 212                 }
 213                 return nlmsg_perm(nlmsg_type, perm, nlmsg_xfrm_perms,
 214                                   sizeof(nlmsg_xfrm_perms));
 215                 break;
 216         case SECCLASS_NETLINK_AUDIT_SOCKET:
 217                 if (selinux_policycap_netlink_xperm()) {
 218                         *perm = NETLINK_AUDIT_SOCKET__NLMSG;
 219                         return 0;
 220                 } else if ((nlmsg_type >= AUDIT_FIRST_USER_MSG &&
 221                             nlmsg_type <= AUDIT_LAST_USER_MSG) ||
 222                            (nlmsg_type >= AUDIT_FIRST_USER_MSG2 &&
 223                             nlmsg_type <= AUDIT_LAST_USER_MSG2)) {
 224                         *perm = NETLINK_AUDIT_SOCKET__NLMSG_RELAY;
 225                         return 0;
 226                 }
 227                 return nlmsg_perm(nlmsg_type, perm, nlmsg_audit_perms,
 228                                   sizeof(nlmsg_audit_perms));
 229                 break;
 230         }
 231
 232         /* No messaging from userspace, or class unknown/unhandled */
 233         return -ENOENT;
 234 }