linux/net/bridge/br_netlink_tunnel.c
Nikolay Aleksandrov 9433944368 net: bridge: notify on vlan tunnel changes done via the old api
If someone uses the old vlan API to configure tunnel mappings we'll only
generate the old-style full port notification. That would be a problem
if we are monitoring the new vlan notifications for changes. The patch
resolves the issue by adding vlan notifications to the old tunnel netlink
code. As usual we try to compress the notifications for as many vlans
in a range as possible, thus a vlan tunnel change is considered able
to enter the "current" vlan notification range if:
 1. vlan exists
 2. it has actually changed (curr_change == true)
 3. it passes all standard vlan notification range checks done by
    br_vlan_can_enter_range() such as option equality, id continuity etc

Note that vlan tunnel changes (add/del) are considered a part of vlan
options so only RTM_NEWVLAN notification is generated with the relevant
information inside.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-12 15:18:24 -07:00

340 lines
7.9 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Bridge per vlan tunnel port dst_metadata netlink control interface
*
* Authors:
* Roopa Prabhu <roopa@cumulusnetworks.com>
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/etherdevice.h>
#include <net/rtnetlink.h>
#include <net/net_namespace.h>
#include <net/sock.h>
#include <uapi/linux/if_bridge.h>
#include <net/dst_metadata.h>
#include "br_private.h"
#include "br_private_tunnel.h"
static size_t __get_vlan_tinfo_size(void)
{
return nla_total_size(0) + /* nest IFLA_BRIDGE_VLAN_TUNNEL_INFO */
nla_total_size(sizeof(u32)) + /* IFLA_BRIDGE_VLAN_TUNNEL_ID */
nla_total_size(sizeof(u16)) + /* IFLA_BRIDGE_VLAN_TUNNEL_VID */
nla_total_size(sizeof(u16)); /* IFLA_BRIDGE_VLAN_TUNNEL_FLAGS */
}
bool vlan_tunid_inrange(const struct net_bridge_vlan *v_curr,
const struct net_bridge_vlan *v_last)
{
__be32 tunid_curr = tunnel_id_to_key32(v_curr->tinfo.tunnel_id);
__be32 tunid_last = tunnel_id_to_key32(v_last->tinfo.tunnel_id);
return (be32_to_cpu(tunid_curr) - be32_to_cpu(tunid_last)) == 1;
}
static int __get_num_vlan_tunnel_infos(struct net_bridge_vlan_group *vg)
{
struct net_bridge_vlan *v, *vtbegin = NULL, *vtend = NULL;
int num_tinfos = 0;
/* Count number of vlan infos */
list_for_each_entry_rcu(v, &vg->vlan_list, vlist) {
/* only a context, bridge vlan not activated */
if (!br_vlan_should_use(v) || !v->tinfo.tunnel_id)
continue;
if (!vtbegin) {
goto initvars;
} else if ((v->vid - vtend->vid) == 1 &&
vlan_tunid_inrange(v, vtend)) {
vtend = v;
continue;
} else {
if ((vtend->vid - vtbegin->vid) > 0)
num_tinfos += 2;
else
num_tinfos += 1;
}
initvars:
vtbegin = v;
vtend = v;
}
if (vtbegin && vtend) {
if ((vtend->vid - vtbegin->vid) > 0)
num_tinfos += 2;
else
num_tinfos += 1;
}
return num_tinfos;
}
int br_get_vlan_tunnel_info_size(struct net_bridge_vlan_group *vg)
{
int num_tinfos;
if (!vg)
return 0;
rcu_read_lock();
num_tinfos = __get_num_vlan_tunnel_infos(vg);
rcu_read_unlock();
return num_tinfos * __get_vlan_tinfo_size();
}
static int br_fill_vlan_tinfo(struct sk_buff *skb, u16 vid,
__be64 tunnel_id, u16 flags)
{
__be32 tid = tunnel_id_to_key32(tunnel_id);
struct nlattr *tmap;
tmap = nla_nest_start_noflag(skb, IFLA_BRIDGE_VLAN_TUNNEL_INFO);
if (!tmap)
return -EMSGSIZE;
if (nla_put_u32(skb, IFLA_BRIDGE_VLAN_TUNNEL_ID,
be32_to_cpu(tid)))
goto nla_put_failure;
if (nla_put_u16(skb, IFLA_BRIDGE_VLAN_TUNNEL_VID,
vid))
goto nla_put_failure;
if (nla_put_u16(skb, IFLA_BRIDGE_VLAN_TUNNEL_FLAGS,
flags))
goto nla_put_failure;
nla_nest_end(skb, tmap);
return 0;
nla_put_failure:
nla_nest_cancel(skb, tmap);
return -EMSGSIZE;
}
static int br_fill_vlan_tinfo_range(struct sk_buff *skb,
struct net_bridge_vlan *vtbegin,
struct net_bridge_vlan *vtend)
{
int err;
if (vtend && (vtend->vid - vtbegin->vid) > 0) {
/* add range to skb */
err = br_fill_vlan_tinfo(skb, vtbegin->vid,
vtbegin->tinfo.tunnel_id,
BRIDGE_VLAN_INFO_RANGE_BEGIN);
if (err)
return err;
err = br_fill_vlan_tinfo(skb, vtend->vid,
vtend->tinfo.tunnel_id,
BRIDGE_VLAN_INFO_RANGE_END);
if (err)
return err;
} else {
err = br_fill_vlan_tinfo(skb, vtbegin->vid,
vtbegin->tinfo.tunnel_id,
0);
if (err)
return err;
}
return 0;
}
int br_fill_vlan_tunnel_info(struct sk_buff *skb,
struct net_bridge_vlan_group *vg)
{
struct net_bridge_vlan *vtbegin = NULL;
struct net_bridge_vlan *vtend = NULL;
struct net_bridge_vlan *v;
int err;
/* Count number of vlan infos */
list_for_each_entry_rcu(v, &vg->vlan_list, vlist) {
/* only a context, bridge vlan not activated */
if (!br_vlan_should_use(v))
continue;
if (!v->tinfo.tunnel_dst)
continue;
if (!vtbegin) {
goto initvars;
} else if ((v->vid - vtend->vid) == 1 &&
vlan_tunid_inrange(v, vtend)) {
vtend = v;
continue;
} else {
err = br_fill_vlan_tinfo_range(skb, vtbegin, vtend);
if (err)
return err;
}
initvars:
vtbegin = v;
vtend = v;
}
if (vtbegin) {
err = br_fill_vlan_tinfo_range(skb, vtbegin, vtend);
if (err)
return err;
}
return 0;
}
static const struct nla_policy vlan_tunnel_policy[IFLA_BRIDGE_VLAN_TUNNEL_MAX + 1] = {
[IFLA_BRIDGE_VLAN_TUNNEL_ID] = { .type = NLA_U32 },
[IFLA_BRIDGE_VLAN_TUNNEL_VID] = { .type = NLA_U16 },
[IFLA_BRIDGE_VLAN_TUNNEL_FLAGS] = { .type = NLA_U16 },
};
int br_vlan_tunnel_info(const struct net_bridge_port *p, int cmd,
u16 vid, u32 tun_id, bool *changed)
{
int err = 0;
if (!p)
return -EINVAL;
switch (cmd) {
case RTM_SETLINK:
err = nbp_vlan_tunnel_info_add(p, vid, tun_id);
if (!err)
*changed = true;
break;
case RTM_DELLINK:
if (!nbp_vlan_tunnel_info_delete(p, vid))
*changed = true;
break;
}
return err;
}
int br_parse_vlan_tunnel_info(struct nlattr *attr,
struct vtunnel_info *tinfo)
{
struct nlattr *tb[IFLA_BRIDGE_VLAN_TUNNEL_MAX + 1];
u32 tun_id;
u16 vid, flags = 0;
int err;
memset(tinfo, 0, sizeof(*tinfo));
err = nla_parse_nested_deprecated(tb, IFLA_BRIDGE_VLAN_TUNNEL_MAX,
attr, vlan_tunnel_policy, NULL);
if (err < 0)
return err;
if (!tb[IFLA_BRIDGE_VLAN_TUNNEL_ID] ||
!tb[IFLA_BRIDGE_VLAN_TUNNEL_VID])
return -EINVAL;
tun_id = nla_get_u32(tb[IFLA_BRIDGE_VLAN_TUNNEL_ID]);
vid = nla_get_u16(tb[IFLA_BRIDGE_VLAN_TUNNEL_VID]);
if (vid >= VLAN_VID_MASK)
return -ERANGE;
if (tb[IFLA_BRIDGE_VLAN_TUNNEL_FLAGS])
flags = nla_get_u16(tb[IFLA_BRIDGE_VLAN_TUNNEL_FLAGS]);
tinfo->tunid = tun_id;
tinfo->vid = vid;
tinfo->flags = flags;
return 0;
}
/* send a notification if v_curr can't enter the range and start a new one */
static void __vlan_tunnel_handle_range(const struct net_bridge_port *p,
struct net_bridge_vlan **v_start,
struct net_bridge_vlan **v_end,
int v_curr, bool curr_change)
{
struct net_bridge_vlan_group *vg;
struct net_bridge_vlan *v;
vg = nbp_vlan_group(p);
if (!vg)
return;
v = br_vlan_find(vg, v_curr);
if (!*v_start)
goto out_init;
if (v && curr_change && br_vlan_can_enter_range(v, *v_end)) {
*v_end = v;
return;
}
br_vlan_notify(p->br, p, (*v_start)->vid, (*v_end)->vid, RTM_NEWVLAN);
out_init:
/* we start a range only if there are any changes to notify about */
*v_start = curr_change ? v : NULL;
*v_end = *v_start;
}
int br_process_vlan_tunnel_info(const struct net_bridge *br,
const struct net_bridge_port *p, int cmd,
struct vtunnel_info *tinfo_curr,
struct vtunnel_info *tinfo_last,
bool *changed)
{
int err;
if (tinfo_curr->flags & BRIDGE_VLAN_INFO_RANGE_BEGIN) {
if (tinfo_last->flags & BRIDGE_VLAN_INFO_RANGE_BEGIN)
return -EINVAL;
memcpy(tinfo_last, tinfo_curr, sizeof(struct vtunnel_info));
} else if (tinfo_curr->flags & BRIDGE_VLAN_INFO_RANGE_END) {
struct net_bridge_vlan *v_start = NULL, *v_end = NULL;
int t, v;
if (!(tinfo_last->flags & BRIDGE_VLAN_INFO_RANGE_BEGIN))
return -EINVAL;
if ((tinfo_curr->vid - tinfo_last->vid) !=
(tinfo_curr->tunid - tinfo_last->tunid))
return -EINVAL;
t = tinfo_last->tunid;
for (v = tinfo_last->vid; v <= tinfo_curr->vid; v++) {
bool curr_change = false;
err = br_vlan_tunnel_info(p, cmd, v, t, &curr_change);
if (err)
break;
t++;
if (curr_change)
*changed = curr_change;
__vlan_tunnel_handle_range(p, &v_start, &v_end, v,
curr_change);
}
if (v_start && v_end)
br_vlan_notify(br, p, v_start->vid, v_end->vid,
RTM_NEWVLAN);
if (err)
return err;
memset(tinfo_last, 0, sizeof(struct vtunnel_info));
memset(tinfo_curr, 0, sizeof(struct vtunnel_info));
} else {
if (tinfo_last->flags)
return -EINVAL;
err = br_vlan_tunnel_info(p, cmd, tinfo_curr->vid,
tinfo_curr->tunid, changed);
if (err)
return err;
br_vlan_notify(br, p, tinfo_curr->vid, 0, RTM_NEWVLAN);
memset(tinfo_last, 0, sizeof(struct vtunnel_info));
memset(tinfo_curr, 0, sizeof(struct vtunnel_info));
}
return 0;
}