net/bridge/br_vlan_options.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 // Copyright (c) 2020, Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
   3 #include <linux/kernel.h>
   4 #include <linux/netdevice.h>
   5 #include <linux/rtnetlink.h>
   6 #include <linux/slab.h>
   7 #include <net/ip_tunnels.h>
   8
   9 #include "br_private.h"
  10 #include "br_private_tunnel.h"
  11
  12 static bool __vlan_tun_put(struct sk_buff *skb, const struct net_bridge_vlan *v)
  13 {
  14         __be32 tid = tunnel_id_to_key32(v->tinfo.tunnel_id);
  15         struct nlattr *nest;
  16
  17         if (!v->tinfo.tunnel_dst)
  18                 return true;
  19
  20         nest = nla_nest_start(skb, BRIDGE_VLANDB_ENTRY_TUNNEL_INFO);
  21         if (!nest)
  22                 return false;
  23         if (nla_put_u32(skb, BRIDGE_VLANDB_TINFO_ID, be32_to_cpu(tid))) {
  24                 nla_nest_cancel(skb, nest);
  25                 return false;
  26         }
  27         nla_nest_end(skb, nest);
  28
  29         return true;
  30 }
  31
  32 static bool __vlan_tun_can_enter_range(const struct net_bridge_vlan *v_curr,
  33                                        const struct net_bridge_vlan *range_end)
  34 {
  35         return (!v_curr->tinfo.tunnel_dst && !range_end->tinfo.tunnel_dst) ||
  36                vlan_tunid_inrange(v_curr, range_end);
  37 }
  38
  39 /* check if the options' state of v_curr allow it to enter the range */
  40 bool br_vlan_opts_eq_range(const struct net_bridge_vlan *v_curr,
  41                            const struct net_bridge_vlan *range_end)
  42 {
  43         return v_curr->state == range_end->state &&
  44                __vlan_tun_can_enter_range(v_curr, range_end);
  45 }
  46
  47 bool br_vlan_opts_fill(struct sk_buff *skb, const struct net_bridge_vlan *v)
  48 {
  49         return !nla_put_u8(skb, BRIDGE_VLANDB_ENTRY_STATE,
  50                            br_vlan_get_state(v)) &&
  51                __vlan_tun_put(skb, v);
  52 }
  53
  54 size_t br_vlan_opts_nl_size(void)
  55 {
  56         return nla_total_size(sizeof(u8)) /* BRIDGE_VLANDB_ENTRY_STATE */
  57                + nla_total_size(0) /* BRIDGE_VLANDB_ENTRY_TUNNEL_INFO */
  58                + nla_total_size(sizeof(u32)); /* BRIDGE_VLANDB_TINFO_ID */
  59 }
  60
  61 static int br_vlan_modify_state(struct net_bridge_vlan_group *vg,
  62                                 struct net_bridge_vlan *v,
  63                                 u8 state,
  64                                 bool *changed,
  65                                 struct netlink_ext_ack *extack)
  66 {
  67         struct net_bridge *br;
  68
  69         ASSERT_RTNL();
  70
  71         if (state > BR_STATE_BLOCKING) {
  72                 NL_SET_ERR_MSG_MOD(extack, "Invalid vlan state");
  73                 return -EINVAL;
  74         }
  75
  76         if (br_vlan_is_brentry(v))
  77                 br = v->br;
  78         else
  79                 br = v->port->br;
  80
  81         if (br->stp_enabled == BR_KERNEL_STP) {
  82                 NL_SET_ERR_MSG_MOD(extack, "Can't modify vlan state when using kernel STP");
  83                 return -EBUSY;
  84         }
  85
  86         if (v->state == state)
  87                 return 0;
  88
  89         if (v->vid == br_get_pvid(vg))
  90                 br_vlan_set_pvid_state(vg, state);
  91
  92         br_vlan_set_state(v, state);
  93         *changed = true;
  94
  95         return 0;
  96 }
  97
  98 static const struct nla_policy br_vlandb_tinfo_pol[BRIDGE_VLANDB_TINFO_MAX + 1] = {
  99         [BRIDGE_VLANDB_TINFO_ID]        = { .type = NLA_U32 },
 100         [BRIDGE_VLANDB_TINFO_CMD]       = { .type = NLA_U32 },
 101 };
 102
 103 static int br_vlan_modify_tunnel(const struct net_bridge_port *p,
 104                                  struct net_bridge_vlan *v,
 105                                  struct nlattr **tb,
 106                                  bool *changed,
 107                                  struct netlink_ext_ack *extack)
 108 {
 109         struct nlattr *tun_tb[BRIDGE_VLANDB_TINFO_MAX + 1], *attr;
 110         struct bridge_vlan_info *vinfo;
 111         u32 tun_id = 0;
 112         int cmd, err;
 113
 114         if (!p) {
 115                 NL_SET_ERR_MSG_MOD(extack, "Can't modify tunnel mapping of non-port vlans");
 116                 return -EINVAL;
 117         }
 118         if (!(p->flags & BR_VLAN_TUNNEL)) {
 119                 NL_SET_ERR_MSG_MOD(extack, "Port doesn't have tunnel flag set");
 120                 return -EINVAL;
 121         }
 122
 123         attr = tb[BRIDGE_VLANDB_ENTRY_TUNNEL_INFO];
 124         err = nla_parse_nested(tun_tb, BRIDGE_VLANDB_TINFO_MAX, attr,
 125                                br_vlandb_tinfo_pol, extack);
 126         if (err)
 127                 return err;
 128
 129         if (!tun_tb[BRIDGE_VLANDB_TINFO_CMD]) {
 130                 NL_SET_ERR_MSG_MOD(extack, "Missing tunnel command attribute");
 131                 return -ENOENT;
 132         }
 133         cmd = nla_get_u32(tun_tb[BRIDGE_VLANDB_TINFO_CMD]);
 134         switch (cmd) {
 135         case RTM_SETLINK:
 136                 if (!tun_tb[BRIDGE_VLANDB_TINFO_ID]) {
 137                         NL_SET_ERR_MSG_MOD(extack, "Missing tunnel id attribute");
 138                         return -ENOENT;
 139                 }
 140                 /* when working on vlan ranges this is the starting tunnel id */
 141                 tun_id = nla_get_u32(tun_tb[BRIDGE_VLANDB_TINFO_ID]);
 142                 /* vlan info attr is guaranteed by br_vlan_rtm_process_one */
 143                 vinfo = nla_data(tb[BRIDGE_VLANDB_ENTRY_INFO]);
 144                 /* tunnel ids are mapped to each vlan in increasing order,
 145                  * the starting vlan is in BRIDGE_VLANDB_ENTRY_INFO and v is the
 146                  * current vlan, so we compute: tun_id + v - vinfo->vid
 147                  */
 148                 tun_id += v->vid - vinfo->vid;
 149                 break;
 150         case RTM_DELLINK:
 151                 break;
 152         default:
 153                 NL_SET_ERR_MSG_MOD(extack, "Unsupported tunnel command");
 154                 return -EINVAL;
 155         }
 156
 157         return br_vlan_tunnel_info(p, cmd, v->vid, tun_id, changed);
 158 }
 159
 160 static int br_vlan_process_one_opts(const struct net_bridge *br,
 161                                     const struct net_bridge_port *p,
 162                                     struct net_bridge_vlan_group *vg,
 163                                     struct net_bridge_vlan *v,
 164                                     struct nlattr **tb,
 165                                     bool *changed,
 166                                     struct netlink_ext_ack *extack)
 167 {
 168         int err;
 169
 170         *changed = false;
 171         if (tb[BRIDGE_VLANDB_ENTRY_STATE]) {
 172                 u8 state = nla_get_u8(tb[BRIDGE_VLANDB_ENTRY_STATE]);
 173
 174                 err = br_vlan_modify_state(vg, v, state, changed, extack);
 175                 if (err)
 176                         return err;
 177         }
 178         if (tb[BRIDGE_VLANDB_ENTRY_TUNNEL_INFO]) {
 179                 err = br_vlan_modify_tunnel(p, v, tb, changed, extack);
 180                 if (err)
 181                         return err;
 182         }
 183
 184         return 0;
 185 }
 186
 187 int br_vlan_process_options(const struct net_bridge *br,
 188                             const struct net_bridge_port *p,
 189                             struct net_bridge_vlan *range_start,
 190                             struct net_bridge_vlan *range_end,
 191                             struct nlattr **tb,
 192                             struct netlink_ext_ack *extack)
 193 {
 194         struct net_bridge_vlan *v, *curr_start = NULL, *curr_end = NULL;
 195         struct net_bridge_vlan_group *vg;
 196         int vid, err = 0;
 197         u16 pvid;
 198
 199         if (p)
 200                 vg = nbp_vlan_group(p);
 201         else
 202                 vg = br_vlan_group(br);
 203
 204         if (!range_start || !br_vlan_should_use(range_start)) {
 205                 NL_SET_ERR_MSG_MOD(extack, "Vlan range start doesn't exist, can't process options");
 206                 return -ENOENT;
 207         }
 208         if (!range_end || !br_vlan_should_use(range_end)) {
 209                 NL_SET_ERR_MSG_MOD(extack, "Vlan range end doesn't exist, can't process options");
 210                 return -ENOENT;
 211         }
 212
 213         pvid = br_get_pvid(vg);
 214         for (vid = range_start->vid; vid <= range_end->vid; vid++) {
 215                 bool changed = false;
 216
 217                 v = br_vlan_find(vg, vid);
 218                 if (!v || !br_vlan_should_use(v)) {
 219                         NL_SET_ERR_MSG_MOD(extack, "Vlan in range doesn't exist, can't process options");
 220                         err = -ENOENT;
 221                         break;
 222                 }
 223
 224                 err = br_vlan_process_one_opts(br, p, vg, v, tb, &changed,
 225                                                extack);
 226                 if (err)
 227                         break;
 228
 229                 if (changed) {
 230                         /* vlan options changed, check for range */
 231                         if (!curr_start) {
 232                                 curr_start = v;
 233                                 curr_end = v;
 234                                 continue;
 235                         }
 236
 237                         if (v->vid == pvid ||
 238                             !br_vlan_can_enter_range(v, curr_end)) {
 239                                 br_vlan_notify(br, p, curr_start->vid,
 240                                                curr_end->vid, RTM_NEWVLAN);
 241                                 curr_start = v;
 242                         }
 243                         curr_end = v;
 244                 } else {
 245                         /* nothing changed and nothing to notify yet */
 246                         if (!curr_start)
 247                                 continue;
 248
 249                         br_vlan_notify(br, p, curr_start->vid, curr_end->vid,
 250                                        RTM_NEWVLAN);
 251                         curr_start = NULL;
 252                         curr_end = NULL;
 253                 }
 254         }
 255         if (curr_start)
 256                 br_vlan_notify(br, p, curr_start->vid, curr_end->vid,
 257                                RTM_NEWVLAN);
 258
 259         return err;
 260 }