net/8021q/vlan_netlink.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *      VLAN netlink control interface
   4  *
   5  *      Copyright (c) 2007 Patrick McHardy <kaber@trash.net>
   6  */
   7
   8 #include <linux/kernel.h>
   9 #include <linux/netdevice.h>
  10 #include <linux/if_vlan.h>
  11 #include <linux/module.h>
  12 #include <net/net_namespace.h>
  13 #include <net/netlink.h>
  14 #include <net/rtnetlink.h>
  15 #include "vlan.h"
  16
  17
  18 static const struct nla_policy vlan_policy[IFLA_VLAN_MAX + 1] = {
  19         [IFLA_VLAN_ID]          = { .type = NLA_U16 },
  20         [IFLA_VLAN_FLAGS]       = { .len = sizeof(struct ifla_vlan_flags) },
  21         [IFLA_VLAN_EGRESS_QOS]  = { .type = NLA_NESTED },
  22         [IFLA_VLAN_INGRESS_QOS] = { .type = NLA_NESTED },
  23         [IFLA_VLAN_PROTOCOL]    = { .type = NLA_U16 },
  24 };
  25
  26 static const struct nla_policy vlan_map_policy[IFLA_VLAN_QOS_MAX + 1] = {
  27         [IFLA_VLAN_QOS_MAPPING] = { .len = sizeof(struct ifla_vlan_qos_mapping) },
  28 };
  29
  30
  31 static inline int vlan_validate_qos_map(struct nlattr *attr)
  32 {
  33         if (!attr)
  34                 return 0;
  35         return nla_validate_nested_deprecated(attr, IFLA_VLAN_QOS_MAX,
  36                                               vlan_map_policy, NULL);
  37 }
  38
  39 static int vlan_validate(struct nlattr *tb[], struct nlattr *data[],
  40                          struct netlink_ext_ack *extack)
  41 {
  42         struct ifla_vlan_flags *flags;
  43         u16 id;
  44         int err;
  45
  46         if (tb[IFLA_ADDRESS]) {
  47                 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) {
  48                         NL_SET_ERR_MSG_MOD(extack, "Invalid link address");
  49                         return -EINVAL;
  50                 }
  51                 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) {
  52                         NL_SET_ERR_MSG_MOD(extack, "Invalid link address");
  53                         return -EADDRNOTAVAIL;
  54                 }
  55         }
  56
  57         if (!data) {
  58                 NL_SET_ERR_MSG_MOD(extack, "VLAN properties not specified");
  59                 return -EINVAL;
  60         }
  61
  62         if (data[IFLA_VLAN_PROTOCOL]) {
  63                 switch (nla_get_be16(data[IFLA_VLAN_PROTOCOL])) {
  64                 case htons(ETH_P_8021Q):
  65                 case htons(ETH_P_8021AD):
  66                         break;
  67                 default:
  68                         NL_SET_ERR_MSG_MOD(extack, "Invalid VLAN protocol");
  69                         return -EPROTONOSUPPORT;
  70                 }
  71         }
  72
  73         if (data[IFLA_VLAN_ID]) {
  74                 id = nla_get_u16(data[IFLA_VLAN_ID]);
  75                 if (id >= VLAN_VID_MASK) {
  76                         NL_SET_ERR_MSG_MOD(extack, "Invalid VLAN id");
  77                         return -ERANGE;
  78                 }
  79         }
  80         if (data[IFLA_VLAN_FLAGS]) {
  81                 flags = nla_data(data[IFLA_VLAN_FLAGS]);
  82                 if ((flags->flags & flags->mask) &
  83                     ~(VLAN_FLAG_REORDER_HDR | VLAN_FLAG_GVRP |
  84                       VLAN_FLAG_LOOSE_BINDING | VLAN_FLAG_MVRP |
  85                       VLAN_FLAG_BRIDGE_BINDING)) {
  86                         NL_SET_ERR_MSG_MOD(extack, "Invalid VLAN flags");
  87                         return -EINVAL;
  88                 }
  89         }
  90
  91         err = vlan_validate_qos_map(data[IFLA_VLAN_INGRESS_QOS]);
  92         if (err < 0) {
  93                 NL_SET_ERR_MSG_MOD(extack, "Invalid ingress QOS map");
  94                 return err;
  95         }
  96         err = vlan_validate_qos_map(data[IFLA_VLAN_EGRESS_QOS]);
  97         if (err < 0) {
  98                 NL_SET_ERR_MSG_MOD(extack, "Invalid egress QOS map");
  99                 return err;
 100         }
 101         return 0;
 102 }
 103
 104 static int vlan_changelink(struct net_device *dev, struct nlattr *tb[],
 105                            struct nlattr *data[],
 106                            struct netlink_ext_ack *extack)
 107 {
 108         struct ifla_vlan_flags *flags;
 109         struct ifla_vlan_qos_mapping *m;
 110         struct nlattr *attr;
 111         int rem, err;
 112
 113         if (data[IFLA_VLAN_FLAGS]) {
 114                 flags = nla_data(data[IFLA_VLAN_FLAGS]);
 115                 err = vlan_dev_change_flags(dev, flags->flags, flags->mask);
 116                 if (err)
 117                         return err;
 118         }
 119         if (data[IFLA_VLAN_INGRESS_QOS]) {
 120                 nla_for_each_nested_type(attr, IFLA_VLAN_QOS_MAPPING,
 121                                          data[IFLA_VLAN_INGRESS_QOS], rem) {
 122                         m = nla_data(attr);
 123                         vlan_dev_set_ingress_priority(dev, m->to, m->from);
 124                 }
 125         }
 126         if (data[IFLA_VLAN_EGRESS_QOS]) {
 127                 nla_for_each_nested_type(attr, IFLA_VLAN_QOS_MAPPING,
 128                                          data[IFLA_VLAN_EGRESS_QOS], rem) {
 129                         m = nla_data(attr);
 130                         err = vlan_dev_set_egress_priority(dev, m->from, m->to);
 131                         if (err)
 132                                 return err;
 133                 }
 134         }
 135         return 0;
 136 }
 137
 138 static int vlan_newlink(struct net *src_net, struct net_device *dev,
 139                         struct nlattr *tb[], struct nlattr *data[],
 140                         struct netlink_ext_ack *extack)
 141 {
 142         struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
 143         struct net_device *real_dev;
 144         unsigned int max_mtu;
 145         __be16 proto;
 146         int err;
 147
 148         if (!data[IFLA_VLAN_ID]) {
 149                 NL_SET_ERR_MSG_MOD(extack, "VLAN id not specified");
 150                 return -EINVAL;
 151         }
 152
 153         if (!tb[IFLA_LINK]) {
 154                 NL_SET_ERR_MSG_MOD(extack, "link not specified");
 155                 return -EINVAL;
 156         }
 157
 158         real_dev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
 159         if (!real_dev) {
 160                 NL_SET_ERR_MSG_MOD(extack, "link does not exist");
 161                 return -ENODEV;
 162         }
 163
 164         proto = nla_get_be16_default(data[IFLA_VLAN_PROTOCOL],
 165                                      htons(ETH_P_8021Q));
 166
 167         vlan->vlan_proto = proto;
 168         vlan->vlan_id    = nla_get_u16(data[IFLA_VLAN_ID]);
 169         vlan->real_dev   = real_dev;
 170         dev->priv_flags |= (real_dev->priv_flags & IFF_XMIT_DST_RELEASE);
 171         vlan->flags      = VLAN_FLAG_REORDER_HDR;
 172
 173         err = vlan_check_real_dev(real_dev, vlan->vlan_proto, vlan->vlan_id,
 174                                   extack);
 175         if (err < 0)
 176                 return err;
 177
 178         max_mtu = netif_reduces_vlan_mtu(real_dev) ? real_dev->mtu - VLAN_HLEN :
 179                                                      real_dev->mtu;
 180         if (!tb[IFLA_MTU])
 181                 dev->mtu = max_mtu;
 182         else if (dev->mtu > max_mtu)
 183                 return -EINVAL;
 184
 185         /* Note: If this initial vlan_changelink() fails, we need
 186          * to call vlan_dev_free_egress_priority() to free memory.
 187          */
 188         err = vlan_changelink(dev, tb, data, extack);
 189
 190         if (!err)
 191                 err = register_vlan_dev(dev, extack);
 192
 193         if (err)
 194                 vlan_dev_free_egress_priority(dev);
 195         return err;
 196 }
 197
 198 static inline size_t vlan_qos_map_size(unsigned int n)
 199 {
 200         if (n == 0)
 201                 return 0;
 202         /* IFLA_VLAN_{EGRESS,INGRESS}_QOS + n * IFLA_VLAN_QOS_MAPPING */
 203         return nla_total_size(sizeof(struct nlattr)) +
 204                nla_total_size(sizeof(struct ifla_vlan_qos_mapping)) * n;
 205 }
 206
 207 static size_t vlan_get_size(const struct net_device *dev)
 208 {
 209         struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
 210
 211         return nla_total_size(2) +      /* IFLA_VLAN_PROTOCOL */
 212                nla_total_size(2) +      /* IFLA_VLAN_ID */
 213                nla_total_size(sizeof(struct ifla_vlan_flags)) + /* IFLA_VLAN_FLAGS */
 214                vlan_qos_map_size(vlan->nr_ingress_mappings) +
 215                vlan_qos_map_size(vlan->nr_egress_mappings);
 216 }
 217
 218 static int vlan_fill_info(struct sk_buff *skb, const struct net_device *dev)
 219 {
 220         struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
 221         struct vlan_priority_tci_mapping *pm;
 222         struct ifla_vlan_flags f;
 223         struct ifla_vlan_qos_mapping m;
 224         struct nlattr *nest;
 225         unsigned int i;
 226
 227         if (nla_put_be16(skb, IFLA_VLAN_PROTOCOL, vlan->vlan_proto) ||
 228             nla_put_u16(skb, IFLA_VLAN_ID, vlan->vlan_id))
 229                 goto nla_put_failure;
 230         if (vlan->flags) {
 231                 f.flags = vlan->flags;
 232                 f.mask  = ~0;
 233                 if (nla_put(skb, IFLA_VLAN_FLAGS, sizeof(f), &f))
 234                         goto nla_put_failure;
 235         }
 236         if (vlan->nr_ingress_mappings) {
 237                 nest = nla_nest_start_noflag(skb, IFLA_VLAN_INGRESS_QOS);
 238                 if (nest == NULL)
 239                         goto nla_put_failure;
 240
 241                 for (i = 0; i < ARRAY_SIZE(vlan->ingress_priority_map); i++) {
 242                         if (!vlan->ingress_priority_map[i])
 243                                 continue;
 244
 245                         m.from = i;
 246                         m.to   = vlan->ingress_priority_map[i];
 247                         if (nla_put(skb, IFLA_VLAN_QOS_MAPPING,
 248                                     sizeof(m), &m))
 249                                 goto nla_put_failure;
 250                 }
 251                 nla_nest_end(skb, nest);
 252         }
 253
 254         if (vlan->nr_egress_mappings) {
 255                 nest = nla_nest_start_noflag(skb, IFLA_VLAN_EGRESS_QOS);
 256                 if (nest == NULL)
 257                         goto nla_put_failure;
 258
 259                 for (i = 0; i < ARRAY_SIZE(vlan->egress_priority_map); i++) {
 260                         for (pm = vlan->egress_priority_map[i]; pm;
 261                              pm = pm->next) {
 262                                 if (!pm->vlan_qos)
 263                                         continue;
 264
 265                                 m.from = pm->priority;
 266                                 m.to   = (pm->vlan_qos >> 13) & 0x7;
 267                                 if (nla_put(skb, IFLA_VLAN_QOS_MAPPING,
 268                                             sizeof(m), &m))
 269                                         goto nla_put_failure;
 270                         }
 271                 }
 272                 nla_nest_end(skb, nest);
 273         }
 274         return 0;
 275
 276 nla_put_failure:
 277         return -EMSGSIZE;
 278 }
 279
 280 static struct net *vlan_get_link_net(const struct net_device *dev)
 281 {
 282         struct net_device *real_dev = vlan_dev_priv(dev)->real_dev;
 283
 284         return dev_net(real_dev);
 285 }
 286
 287 struct rtnl_link_ops vlan_link_ops __read_mostly = {
 288         .kind           = "vlan",
 289         .maxtype        = IFLA_VLAN_MAX,
 290         .policy         = vlan_policy,
 291         .priv_size      = sizeof(struct vlan_dev_priv),
 292         .setup          = vlan_setup,
 293         .validate       = vlan_validate,
 294         .newlink        = vlan_newlink,
 295         .changelink     = vlan_changelink,
 296         .dellink        = unregister_vlan_dev,
 297         .get_size       = vlan_get_size,
 298         .fill_info      = vlan_fill_info,
 299         .get_link_net   = vlan_get_link_net,
 300 };
 301
 302 int __init vlan_netlink_init(void)
 303 {
 304         return rtnl_link_register(&vlan_link_ops);
 305 }
 306
 307 void __exit vlan_netlink_fini(void)
 308 {
 309         rtnl_link_unregister(&vlan_link_ops);
 310 }
 311
 312 MODULE_ALIAS_RTNL_LINK("vlan");