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linux/net/batman-adv/bat_v.c
Sven Eckelmann 9264c85c8b batman-adv: Add inconsistent gateway netlink dump detection
The netlink dump functionality transfers a large number of entries from the
kernel to userspace. It is rather likely that the transfer has to
interrupted and later continued. During that time, it can happen that
either new entries are added or removed. The userspace could than either
receive some entries multiple times or miss entries.

Commit 670dc2833d ("netlink: advertise incomplete dumps") introduced a
mechanism to inform userspace about this problem. Userspace can then decide
whether it is necessary or not to retry dumping the information again.

The netlink dump functions have to be switched to exclusive locks to avoid
changes while the current message is prepared. And an external generation
sequence counter is introduced which tracks all modifications of the list.

Reported-by: Matthias Schiffer <mschiffer@universe-factory.net>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2018-11-12 10:41:51 +01:00

1163 lines
30 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* Copyright (C) 2013-2018 B.A.T.M.A.N. contributors:
*
* Linus Lüssing, Marek Lindner
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include "bat_v.h"
#include "main.h"
#include <linux/atomic.h>
#include <linux/cache.h>
#include <linux/errno.h>
#include <linux/if_ether.h>
#include <linux/init.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/kref.h>
#include <linux/list.h>
#include <linux/netdevice.h>
#include <linux/netlink.h>
#include <linux/rculist.h>
#include <linux/rcupdate.h>
#include <linux/seq_file.h>
#include <linux/spinlock.h>
#include <linux/stddef.h>
#include <linux/types.h>
#include <linux/workqueue.h>
#include <net/genetlink.h>
#include <net/netlink.h>
#include <uapi/linux/batadv_packet.h>
#include <uapi/linux/batman_adv.h>
#include "bat_algo.h"
#include "bat_v_elp.h"
#include "bat_v_ogm.h"
#include "gateway_client.h"
#include "gateway_common.h"
#include "hard-interface.h"
#include "hash.h"
#include "log.h"
#include "netlink.h"
#include "originator.h"
struct sk_buff;
static void batadv_v_iface_activate(struct batadv_hard_iface *hard_iface)
{
struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
struct batadv_hard_iface *primary_if;
primary_if = batadv_primary_if_get_selected(bat_priv);
if (primary_if) {
batadv_v_elp_iface_activate(primary_if, hard_iface);
batadv_hardif_put(primary_if);
}
/* B.A.T.M.A.N. V does not use any queuing mechanism, therefore it can
* set the interface as ACTIVE right away, without any risk of race
* condition
*/
if (hard_iface->if_status == BATADV_IF_TO_BE_ACTIVATED)
hard_iface->if_status = BATADV_IF_ACTIVE;
}
static int batadv_v_iface_enable(struct batadv_hard_iface *hard_iface)
{
int ret;
ret = batadv_v_elp_iface_enable(hard_iface);
if (ret < 0)
return ret;
ret = batadv_v_ogm_iface_enable(hard_iface);
if (ret < 0)
batadv_v_elp_iface_disable(hard_iface);
return ret;
}
static void batadv_v_iface_disable(struct batadv_hard_iface *hard_iface)
{
batadv_v_elp_iface_disable(hard_iface);
}
static void batadv_v_primary_iface_set(struct batadv_hard_iface *hard_iface)
{
batadv_v_elp_primary_iface_set(hard_iface);
batadv_v_ogm_primary_iface_set(hard_iface);
}
/**
* batadv_v_iface_update_mac() - react to hard-interface MAC address change
* @hard_iface: the modified interface
*
* If the modified interface is the primary one, update the originator
* address in the ELP and OGM messages to reflect the new MAC address.
*/
static void batadv_v_iface_update_mac(struct batadv_hard_iface *hard_iface)
{
struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
struct batadv_hard_iface *primary_if;
primary_if = batadv_primary_if_get_selected(bat_priv);
if (primary_if != hard_iface)
goto out;
batadv_v_primary_iface_set(hard_iface);
out:
if (primary_if)
batadv_hardif_put(primary_if);
}
static void
batadv_v_hardif_neigh_init(struct batadv_hardif_neigh_node *hardif_neigh)
{
ewma_throughput_init(&hardif_neigh->bat_v.throughput);
INIT_WORK(&hardif_neigh->bat_v.metric_work,
batadv_v_elp_throughput_metric_update);
}
#ifdef CONFIG_BATMAN_ADV_DEBUGFS
/**
* batadv_v_orig_print_neigh() - print neighbors for the originator table
* @orig_node: the orig_node for which the neighbors are printed
* @if_outgoing: outgoing interface for these entries
* @seq: debugfs table seq_file struct
*
* Must be called while holding an rcu lock.
*/
static void
batadv_v_orig_print_neigh(struct batadv_orig_node *orig_node,
struct batadv_hard_iface *if_outgoing,
struct seq_file *seq)
{
struct batadv_neigh_node *neigh_node;
struct batadv_neigh_ifinfo *n_ifinfo;
hlist_for_each_entry_rcu(neigh_node, &orig_node->neigh_list, list) {
n_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing);
if (!n_ifinfo)
continue;
seq_printf(seq, " %pM (%9u.%1u)",
neigh_node->addr,
n_ifinfo->bat_v.throughput / 10,
n_ifinfo->bat_v.throughput % 10);
batadv_neigh_ifinfo_put(n_ifinfo);
}
}
/**
* batadv_v_hardif_neigh_print() - print a single ELP neighbour node
* @seq: neighbour table seq_file struct
* @hardif_neigh: hardif neighbour information
*/
static void
batadv_v_hardif_neigh_print(struct seq_file *seq,
struct batadv_hardif_neigh_node *hardif_neigh)
{
int last_secs, last_msecs;
u32 throughput;
last_secs = jiffies_to_msecs(jiffies - hardif_neigh->last_seen) / 1000;
last_msecs = jiffies_to_msecs(jiffies - hardif_neigh->last_seen) % 1000;
throughput = ewma_throughput_read(&hardif_neigh->bat_v.throughput);
seq_printf(seq, "%pM %4i.%03is (%9u.%1u) [%10s]\n",
hardif_neigh->addr, last_secs, last_msecs, throughput / 10,
throughput % 10, hardif_neigh->if_incoming->net_dev->name);
}
/**
* batadv_v_neigh_print() - print the single hop neighbour list
* @bat_priv: the bat priv with all the soft interface information
* @seq: neighbour table seq_file struct
*/
static void batadv_v_neigh_print(struct batadv_priv *bat_priv,
struct seq_file *seq)
{
struct net_device *net_dev = (struct net_device *)seq->private;
struct batadv_hardif_neigh_node *hardif_neigh;
struct batadv_hard_iface *hard_iface;
int batman_count = 0;
seq_puts(seq,
" Neighbor last-seen ( throughput) [ IF]\n");
rcu_read_lock();
list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
if (hard_iface->soft_iface != net_dev)
continue;
hlist_for_each_entry_rcu(hardif_neigh,
&hard_iface->neigh_list, list) {
batadv_v_hardif_neigh_print(seq, hardif_neigh);
batman_count++;
}
}
rcu_read_unlock();
if (batman_count == 0)
seq_puts(seq, "No batman nodes in range ...\n");
}
#endif
/**
* batadv_v_neigh_dump_neigh() - Dump a neighbour into a message
* @msg: Netlink message to dump into
* @portid: Port making netlink request
* @seq: Sequence number of netlink message
* @hardif_neigh: Neighbour to dump
*
* Return: Error code, or 0 on success
*/
static int
batadv_v_neigh_dump_neigh(struct sk_buff *msg, u32 portid, u32 seq,
struct batadv_hardif_neigh_node *hardif_neigh)
{
void *hdr;
unsigned int last_seen_msecs;
u32 throughput;
last_seen_msecs = jiffies_to_msecs(jiffies - hardif_neigh->last_seen);
throughput = ewma_throughput_read(&hardif_neigh->bat_v.throughput);
throughput = throughput * 100;
hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family, NLM_F_MULTI,
BATADV_CMD_GET_NEIGHBORS);
if (!hdr)
return -ENOBUFS;
if (nla_put(msg, BATADV_ATTR_NEIGH_ADDRESS, ETH_ALEN,
hardif_neigh->addr) ||
nla_put_u32(msg, BATADV_ATTR_HARD_IFINDEX,
hardif_neigh->if_incoming->net_dev->ifindex) ||
nla_put_u32(msg, BATADV_ATTR_LAST_SEEN_MSECS,
last_seen_msecs) ||
nla_put_u32(msg, BATADV_ATTR_THROUGHPUT, throughput))
goto nla_put_failure;
genlmsg_end(msg, hdr);
return 0;
nla_put_failure:
genlmsg_cancel(msg, hdr);
return -EMSGSIZE;
}
/**
* batadv_v_neigh_dump_hardif() - Dump the neighbours of a hard interface into
* a message
* @msg: Netlink message to dump into
* @portid: Port making netlink request
* @seq: Sequence number of netlink message
* @bat_priv: The bat priv with all the soft interface information
* @hard_iface: The hard interface to be dumped
* @idx_s: Entries to be skipped
*
* This function assumes the caller holds rcu_read_lock().
*
* Return: Error code, or 0 on success
*/
static int
batadv_v_neigh_dump_hardif(struct sk_buff *msg, u32 portid, u32 seq,
struct batadv_priv *bat_priv,
struct batadv_hard_iface *hard_iface,
int *idx_s)
{
struct batadv_hardif_neigh_node *hardif_neigh;
int idx = 0;
hlist_for_each_entry_rcu(hardif_neigh,
&hard_iface->neigh_list, list) {
if (idx++ < *idx_s)
continue;
if (batadv_v_neigh_dump_neigh(msg, portid, seq, hardif_neigh)) {
*idx_s = idx - 1;
return -EMSGSIZE;
}
}
*idx_s = 0;
return 0;
}
/**
* batadv_v_neigh_dump() - Dump the neighbours of a hard interface into a
* message
* @msg: Netlink message to dump into
* @cb: Control block containing additional options
* @bat_priv: The bat priv with all the soft interface information
* @single_hardif: Limit dumping to this hard interface
*/
static void
batadv_v_neigh_dump(struct sk_buff *msg, struct netlink_callback *cb,
struct batadv_priv *bat_priv,
struct batadv_hard_iface *single_hardif)
{
struct batadv_hard_iface *hard_iface;
int i_hardif = 0;
int i_hardif_s = cb->args[0];
int idx = cb->args[1];
int portid = NETLINK_CB(cb->skb).portid;
rcu_read_lock();
if (single_hardif) {
if (i_hardif_s == 0) {
if (batadv_v_neigh_dump_hardif(msg, portid,
cb->nlh->nlmsg_seq,
bat_priv, single_hardif,
&idx) == 0)
i_hardif++;
}
} else {
list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
if (hard_iface->soft_iface != bat_priv->soft_iface)
continue;
if (i_hardif++ < i_hardif_s)
continue;
if (batadv_v_neigh_dump_hardif(msg, portid,
cb->nlh->nlmsg_seq,
bat_priv, hard_iface,
&idx)) {
i_hardif--;
break;
}
}
}
rcu_read_unlock();
cb->args[0] = i_hardif;
cb->args[1] = idx;
}
#ifdef CONFIG_BATMAN_ADV_DEBUGFS
/**
* batadv_v_orig_print() - print the originator table
* @bat_priv: the bat priv with all the soft interface information
* @seq: debugfs table seq_file struct
* @if_outgoing: the outgoing interface for which this should be printed
*/
static void batadv_v_orig_print(struct batadv_priv *bat_priv,
struct seq_file *seq,
struct batadv_hard_iface *if_outgoing)
{
struct batadv_neigh_node *neigh_node;
struct batadv_hashtable *hash = bat_priv->orig_hash;
int last_seen_msecs, last_seen_secs;
struct batadv_orig_node *orig_node;
struct batadv_neigh_ifinfo *n_ifinfo;
unsigned long last_seen_jiffies;
struct hlist_head *head;
int batman_count = 0;
u32 i;
seq_puts(seq,
" Originator last-seen ( throughput) Nexthop [outgoingIF]: Potential nexthops ...\n");
for (i = 0; i < hash->size; i++) {
head = &hash->table[i];
rcu_read_lock();
hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
neigh_node = batadv_orig_router_get(orig_node,
if_outgoing);
if (!neigh_node)
continue;
n_ifinfo = batadv_neigh_ifinfo_get(neigh_node,
if_outgoing);
if (!n_ifinfo)
goto next;
last_seen_jiffies = jiffies - orig_node->last_seen;
last_seen_msecs = jiffies_to_msecs(last_seen_jiffies);
last_seen_secs = last_seen_msecs / 1000;
last_seen_msecs = last_seen_msecs % 1000;
seq_printf(seq, "%pM %4i.%03is (%9u.%1u) %pM [%10s]:",
orig_node->orig, last_seen_secs,
last_seen_msecs,
n_ifinfo->bat_v.throughput / 10,
n_ifinfo->bat_v.throughput % 10,
neigh_node->addr,
neigh_node->if_incoming->net_dev->name);
batadv_v_orig_print_neigh(orig_node, if_outgoing, seq);
seq_putc(seq, '\n');
batman_count++;
next:
batadv_neigh_node_put(neigh_node);
if (n_ifinfo)
batadv_neigh_ifinfo_put(n_ifinfo);
}
rcu_read_unlock();
}
if (batman_count == 0)
seq_puts(seq, "No batman nodes in range ...\n");
}
#endif
/**
* batadv_v_orig_dump_subentry() - Dump an originator subentry into a message
* @msg: Netlink message to dump into
* @portid: Port making netlink request
* @seq: Sequence number of netlink message
* @bat_priv: The bat priv with all the soft interface information
* @if_outgoing: Limit dump to entries with this outgoing interface
* @orig_node: Originator to dump
* @neigh_node: Single hops neighbour
* @best: Is the best originator
*
* Return: Error code, or 0 on success
*/
static int
batadv_v_orig_dump_subentry(struct sk_buff *msg, u32 portid, u32 seq,
struct batadv_priv *bat_priv,
struct batadv_hard_iface *if_outgoing,
struct batadv_orig_node *orig_node,
struct batadv_neigh_node *neigh_node,
bool best)
{
struct batadv_neigh_ifinfo *n_ifinfo;
unsigned int last_seen_msecs;
u32 throughput;
void *hdr;
n_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing);
if (!n_ifinfo)
return 0;
throughput = n_ifinfo->bat_v.throughput * 100;
batadv_neigh_ifinfo_put(n_ifinfo);
last_seen_msecs = jiffies_to_msecs(jiffies - orig_node->last_seen);
if (if_outgoing != BATADV_IF_DEFAULT &&
if_outgoing != neigh_node->if_incoming)
return 0;
hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family, NLM_F_MULTI,
BATADV_CMD_GET_ORIGINATORS);
if (!hdr)
return -ENOBUFS;
if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN, orig_node->orig) ||
nla_put(msg, BATADV_ATTR_NEIGH_ADDRESS, ETH_ALEN,
neigh_node->addr) ||
nla_put_u32(msg, BATADV_ATTR_HARD_IFINDEX,
neigh_node->if_incoming->net_dev->ifindex) ||
nla_put_u32(msg, BATADV_ATTR_THROUGHPUT, throughput) ||
nla_put_u32(msg, BATADV_ATTR_LAST_SEEN_MSECS,
last_seen_msecs))
goto nla_put_failure;
if (best && nla_put_flag(msg, BATADV_ATTR_FLAG_BEST))
goto nla_put_failure;
genlmsg_end(msg, hdr);
return 0;
nla_put_failure:
genlmsg_cancel(msg, hdr);
return -EMSGSIZE;
}
/**
* batadv_v_orig_dump_entry() - Dump an originator entry into a message
* @msg: Netlink message to dump into
* @portid: Port making netlink request
* @seq: Sequence number of netlink message
* @bat_priv: The bat priv with all the soft interface information
* @if_outgoing: Limit dump to entries with this outgoing interface
* @orig_node: Originator to dump
* @sub_s: Number of sub entries to skip
*
* This function assumes the caller holds rcu_read_lock().
*
* Return: Error code, or 0 on success
*/
static int
batadv_v_orig_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
struct batadv_priv *bat_priv,
struct batadv_hard_iface *if_outgoing,
struct batadv_orig_node *orig_node, int *sub_s)
{
struct batadv_neigh_node *neigh_node_best;
struct batadv_neigh_node *neigh_node;
int sub = 0;
bool best;
neigh_node_best = batadv_orig_router_get(orig_node, if_outgoing);
if (!neigh_node_best)
goto out;
hlist_for_each_entry_rcu(neigh_node, &orig_node->neigh_list, list) {
if (sub++ < *sub_s)
continue;
best = (neigh_node == neigh_node_best);
if (batadv_v_orig_dump_subentry(msg, portid, seq, bat_priv,
if_outgoing, orig_node,
neigh_node, best)) {
batadv_neigh_node_put(neigh_node_best);
*sub_s = sub - 1;
return -EMSGSIZE;
}
}
out:
if (neigh_node_best)
batadv_neigh_node_put(neigh_node_best);
*sub_s = 0;
return 0;
}
/**
* batadv_v_orig_dump_bucket() - Dump an originator bucket into a message
* @msg: Netlink message to dump into
* @portid: Port making netlink request
* @seq: Sequence number of netlink message
* @bat_priv: The bat priv with all the soft interface information
* @if_outgoing: Limit dump to entries with this outgoing interface
* @head: Bucket to be dumped
* @idx_s: Number of entries to be skipped
* @sub: Number of sub entries to be skipped
*
* Return: Error code, or 0 on success
*/
static int
batadv_v_orig_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
struct batadv_priv *bat_priv,
struct batadv_hard_iface *if_outgoing,
struct hlist_head *head, int *idx_s, int *sub)
{
struct batadv_orig_node *orig_node;
int idx = 0;
rcu_read_lock();
hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
if (idx++ < *idx_s)
continue;
if (batadv_v_orig_dump_entry(msg, portid, seq, bat_priv,
if_outgoing, orig_node, sub)) {
rcu_read_unlock();
*idx_s = idx - 1;
return -EMSGSIZE;
}
}
rcu_read_unlock();
*idx_s = 0;
*sub = 0;
return 0;
}
/**
* batadv_v_orig_dump() - Dump the originators into a message
* @msg: Netlink message to dump into
* @cb: Control block containing additional options
* @bat_priv: The bat priv with all the soft interface information
* @if_outgoing: Limit dump to entries with this outgoing interface
*/
static void
batadv_v_orig_dump(struct sk_buff *msg, struct netlink_callback *cb,
struct batadv_priv *bat_priv,
struct batadv_hard_iface *if_outgoing)
{
struct batadv_hashtable *hash = bat_priv->orig_hash;
struct hlist_head *head;
int bucket = cb->args[0];
int idx = cb->args[1];
int sub = cb->args[2];
int portid = NETLINK_CB(cb->skb).portid;
while (bucket < hash->size) {
head = &hash->table[bucket];
if (batadv_v_orig_dump_bucket(msg, portid,
cb->nlh->nlmsg_seq,
bat_priv, if_outgoing, head, &idx,
&sub))
break;
bucket++;
}
cb->args[0] = bucket;
cb->args[1] = idx;
cb->args[2] = sub;
}
static int batadv_v_neigh_cmp(struct batadv_neigh_node *neigh1,
struct batadv_hard_iface *if_outgoing1,
struct batadv_neigh_node *neigh2,
struct batadv_hard_iface *if_outgoing2)
{
struct batadv_neigh_ifinfo *ifinfo1, *ifinfo2;
int ret = 0;
ifinfo1 = batadv_neigh_ifinfo_get(neigh1, if_outgoing1);
if (!ifinfo1)
goto err_ifinfo1;
ifinfo2 = batadv_neigh_ifinfo_get(neigh2, if_outgoing2);
if (!ifinfo2)
goto err_ifinfo2;
ret = ifinfo1->bat_v.throughput - ifinfo2->bat_v.throughput;
batadv_neigh_ifinfo_put(ifinfo2);
err_ifinfo2:
batadv_neigh_ifinfo_put(ifinfo1);
err_ifinfo1:
return ret;
}
static bool batadv_v_neigh_is_sob(struct batadv_neigh_node *neigh1,
struct batadv_hard_iface *if_outgoing1,
struct batadv_neigh_node *neigh2,
struct batadv_hard_iface *if_outgoing2)
{
struct batadv_neigh_ifinfo *ifinfo1, *ifinfo2;
u32 threshold;
bool ret = false;
ifinfo1 = batadv_neigh_ifinfo_get(neigh1, if_outgoing1);
if (!ifinfo1)
goto err_ifinfo1;
ifinfo2 = batadv_neigh_ifinfo_get(neigh2, if_outgoing2);
if (!ifinfo2)
goto err_ifinfo2;
threshold = ifinfo1->bat_v.throughput / 4;
threshold = ifinfo1->bat_v.throughput - threshold;
ret = ifinfo2->bat_v.throughput > threshold;
batadv_neigh_ifinfo_put(ifinfo2);
err_ifinfo2:
batadv_neigh_ifinfo_put(ifinfo1);
err_ifinfo1:
return ret;
}
/**
* batadv_v_init_sel_class() - initialize GW selection class
* @bat_priv: the bat priv with all the soft interface information
*/
static void batadv_v_init_sel_class(struct batadv_priv *bat_priv)
{
/* set default throughput difference threshold to 5Mbps */
atomic_set(&bat_priv->gw.sel_class, 50);
}
static ssize_t batadv_v_store_sel_class(struct batadv_priv *bat_priv,
char *buff, size_t count)
{
u32 old_class, class;
if (!batadv_parse_throughput(bat_priv->soft_iface, buff,
"B.A.T.M.A.N. V GW selection class",
&class))
return -EINVAL;
old_class = atomic_read(&bat_priv->gw.sel_class);
atomic_set(&bat_priv->gw.sel_class, class);
if (old_class != class)
batadv_gw_reselect(bat_priv);
return count;
}
static ssize_t batadv_v_show_sel_class(struct batadv_priv *bat_priv, char *buff)
{
u32 class = atomic_read(&bat_priv->gw.sel_class);
return sprintf(buff, "%u.%u MBit\n", class / 10, class % 10);
}
/**
* batadv_v_gw_throughput_get() - retrieve the GW-bandwidth for a given GW
* @gw_node: the GW to retrieve the metric for
* @bw: the pointer where the metric will be stored. The metric is computed as
* the minimum between the GW advertised throughput and the path throughput to
* it in the mesh
*
* Return: 0 on success, -1 on failure
*/
static int batadv_v_gw_throughput_get(struct batadv_gw_node *gw_node, u32 *bw)
{
struct batadv_neigh_ifinfo *router_ifinfo = NULL;
struct batadv_orig_node *orig_node;
struct batadv_neigh_node *router;
int ret = -1;
orig_node = gw_node->orig_node;
router = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
if (!router)
goto out;
router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
if (!router_ifinfo)
goto out;
/* the GW metric is computed as the minimum between the path throughput
* to reach the GW itself and the advertised bandwidth.
* This gives us an approximation of the effective throughput that the
* client can expect via this particular GW node
*/
*bw = router_ifinfo->bat_v.throughput;
*bw = min_t(u32, *bw, gw_node->bandwidth_down);
ret = 0;
out:
if (router)
batadv_neigh_node_put(router);
if (router_ifinfo)
batadv_neigh_ifinfo_put(router_ifinfo);
return ret;
}
/**
* batadv_v_gw_get_best_gw_node() - retrieve the best GW node
* @bat_priv: the bat priv with all the soft interface information
*
* Return: the GW node having the best GW-metric, NULL if no GW is known
*/
static struct batadv_gw_node *
batadv_v_gw_get_best_gw_node(struct batadv_priv *bat_priv)
{
struct batadv_gw_node *gw_node, *curr_gw = NULL;
u32 max_bw = 0, bw;
rcu_read_lock();
hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.gateway_list, list) {
if (!kref_get_unless_zero(&gw_node->refcount))
continue;
if (batadv_v_gw_throughput_get(gw_node, &bw) < 0)
goto next;
if (curr_gw && bw <= max_bw)
goto next;
if (curr_gw)
batadv_gw_node_put(curr_gw);
curr_gw = gw_node;
kref_get(&curr_gw->refcount);
max_bw = bw;
next:
batadv_gw_node_put(gw_node);
}
rcu_read_unlock();
return curr_gw;
}
/**
* batadv_v_gw_is_eligible() - check if a originator would be selected as GW
* @bat_priv: the bat priv with all the soft interface information
* @curr_gw_orig: originator representing the currently selected GW
* @orig_node: the originator representing the new candidate
*
* Return: true if orig_node can be selected as current GW, false otherwise
*/
static bool batadv_v_gw_is_eligible(struct batadv_priv *bat_priv,
struct batadv_orig_node *curr_gw_orig,
struct batadv_orig_node *orig_node)
{
struct batadv_gw_node *curr_gw, *orig_gw = NULL;
u32 gw_throughput, orig_throughput, threshold;
bool ret = false;
threshold = atomic_read(&bat_priv->gw.sel_class);
curr_gw = batadv_gw_node_get(bat_priv, curr_gw_orig);
if (!curr_gw) {
ret = true;
goto out;
}
if (batadv_v_gw_throughput_get(curr_gw, &gw_throughput) < 0) {
ret = true;
goto out;
}
orig_gw = batadv_gw_node_get(bat_priv, orig_node);
if (!orig_gw)
goto out;
if (batadv_v_gw_throughput_get(orig_gw, &orig_throughput) < 0)
goto out;
if (orig_throughput < gw_throughput)
goto out;
if ((orig_throughput - gw_throughput) < threshold)
goto out;
batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
"Restarting gateway selection: better gateway found (throughput curr: %u, throughput new: %u)\n",
gw_throughput, orig_throughput);
ret = true;
out:
if (curr_gw)
batadv_gw_node_put(curr_gw);
if (orig_gw)
batadv_gw_node_put(orig_gw);
return ret;
}
#ifdef CONFIG_BATMAN_ADV_DEBUGFS
/* fails if orig_node has no router */
static int batadv_v_gw_write_buffer_text(struct batadv_priv *bat_priv,
struct seq_file *seq,
const struct batadv_gw_node *gw_node)
{
struct batadv_gw_node *curr_gw;
struct batadv_neigh_node *router;
struct batadv_neigh_ifinfo *router_ifinfo = NULL;
int ret = -1;
router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
if (!router)
goto out;
router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
if (!router_ifinfo)
goto out;
curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
seq_printf(seq, "%s %pM (%9u.%1u) %pM [%10s]: %u.%u/%u.%u MBit\n",
(curr_gw == gw_node ? "=>" : " "),
gw_node->orig_node->orig,
router_ifinfo->bat_v.throughput / 10,
router_ifinfo->bat_v.throughput % 10, router->addr,
router->if_incoming->net_dev->name,
gw_node->bandwidth_down / 10,
gw_node->bandwidth_down % 10,
gw_node->bandwidth_up / 10,
gw_node->bandwidth_up % 10);
ret = seq_has_overflowed(seq) ? -1 : 0;
if (curr_gw)
batadv_gw_node_put(curr_gw);
out:
if (router_ifinfo)
batadv_neigh_ifinfo_put(router_ifinfo);
if (router)
batadv_neigh_node_put(router);
return ret;
}
/**
* batadv_v_gw_print() - print the gateway list
* @bat_priv: the bat priv with all the soft interface information
* @seq: gateway table seq_file struct
*/
static void batadv_v_gw_print(struct batadv_priv *bat_priv,
struct seq_file *seq)
{
struct batadv_gw_node *gw_node;
int gw_count = 0;
seq_puts(seq,
" Gateway ( throughput) Nexthop [outgoingIF]: advertised uplink bandwidth\n");
rcu_read_lock();
hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.gateway_list, list) {
/* fails if orig_node has no router */
if (batadv_v_gw_write_buffer_text(bat_priv, seq, gw_node) < 0)
continue;
gw_count++;
}
rcu_read_unlock();
if (gw_count == 0)
seq_puts(seq, "No gateways in range ...\n");
}
#endif
/**
* batadv_v_gw_dump_entry() - Dump a gateway into a message
* @msg: Netlink message to dump into
* @portid: Port making netlink request
* @cb: Control block containing additional options
* @bat_priv: The bat priv with all the soft interface information
* @gw_node: Gateway to be dumped
*
* Return: Error code, or 0 on success
*/
static int batadv_v_gw_dump_entry(struct sk_buff *msg, u32 portid,
struct netlink_callback *cb,
struct batadv_priv *bat_priv,
struct batadv_gw_node *gw_node)
{
struct batadv_neigh_ifinfo *router_ifinfo = NULL;
struct batadv_neigh_node *router;
struct batadv_gw_node *curr_gw = NULL;
int ret = 0;
void *hdr;
router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
if (!router)
goto out;
router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
if (!router_ifinfo)
goto out;
curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
&batadv_netlink_family, NLM_F_MULTI,
BATADV_CMD_GET_GATEWAYS);
if (!hdr) {
ret = -ENOBUFS;
goto out;
}
genl_dump_check_consistent(cb, hdr);
ret = -EMSGSIZE;
if (curr_gw == gw_node) {
if (nla_put_flag(msg, BATADV_ATTR_FLAG_BEST)) {
genlmsg_cancel(msg, hdr);
goto out;
}
}
if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
gw_node->orig_node->orig)) {
genlmsg_cancel(msg, hdr);
goto out;
}
if (nla_put_u32(msg, BATADV_ATTR_THROUGHPUT,
router_ifinfo->bat_v.throughput)) {
genlmsg_cancel(msg, hdr);
goto out;
}
if (nla_put(msg, BATADV_ATTR_ROUTER, ETH_ALEN, router->addr)) {
genlmsg_cancel(msg, hdr);
goto out;
}
if (nla_put_string(msg, BATADV_ATTR_HARD_IFNAME,
router->if_incoming->net_dev->name)) {
genlmsg_cancel(msg, hdr);
goto out;
}
if (nla_put_u32(msg, BATADV_ATTR_BANDWIDTH_DOWN,
gw_node->bandwidth_down)) {
genlmsg_cancel(msg, hdr);
goto out;
}
if (nla_put_u32(msg, BATADV_ATTR_BANDWIDTH_UP, gw_node->bandwidth_up)) {
genlmsg_cancel(msg, hdr);
goto out;
}
genlmsg_end(msg, hdr);
ret = 0;
out:
if (curr_gw)
batadv_gw_node_put(curr_gw);
if (router_ifinfo)
batadv_neigh_ifinfo_put(router_ifinfo);
if (router)
batadv_neigh_node_put(router);
return ret;
}
/**
* batadv_v_gw_dump() - Dump gateways into a message
* @msg: Netlink message to dump into
* @cb: Control block containing additional options
* @bat_priv: The bat priv with all the soft interface information
*/
static void batadv_v_gw_dump(struct sk_buff *msg, struct netlink_callback *cb,
struct batadv_priv *bat_priv)
{
int portid = NETLINK_CB(cb->skb).portid;
struct batadv_gw_node *gw_node;
int idx_skip = cb->args[0];
int idx = 0;
spin_lock_bh(&bat_priv->gw.list_lock);
cb->seq = bat_priv->gw.generation << 1 | 1;
hlist_for_each_entry(gw_node, &bat_priv->gw.gateway_list, list) {
if (idx++ < idx_skip)
continue;
if (batadv_v_gw_dump_entry(msg, portid, cb, bat_priv,
gw_node)) {
idx_skip = idx - 1;
goto unlock;
}
}
idx_skip = idx;
unlock:
spin_unlock_bh(&bat_priv->gw.list_lock);
cb->args[0] = idx_skip;
}
static struct batadv_algo_ops batadv_batman_v __read_mostly = {
.name = "BATMAN_V",
.iface = {
.activate = batadv_v_iface_activate,
.enable = batadv_v_iface_enable,
.disable = batadv_v_iface_disable,
.update_mac = batadv_v_iface_update_mac,
.primary_set = batadv_v_primary_iface_set,
},
.neigh = {
.hardif_init = batadv_v_hardif_neigh_init,
.cmp = batadv_v_neigh_cmp,
.is_similar_or_better = batadv_v_neigh_is_sob,
#ifdef CONFIG_BATMAN_ADV_DEBUGFS
.print = batadv_v_neigh_print,
#endif
.dump = batadv_v_neigh_dump,
},
.orig = {
#ifdef CONFIG_BATMAN_ADV_DEBUGFS
.print = batadv_v_orig_print,
#endif
.dump = batadv_v_orig_dump,
},
.gw = {
.init_sel_class = batadv_v_init_sel_class,
.store_sel_class = batadv_v_store_sel_class,
.show_sel_class = batadv_v_show_sel_class,
.get_best_gw_node = batadv_v_gw_get_best_gw_node,
.is_eligible = batadv_v_gw_is_eligible,
#ifdef CONFIG_BATMAN_ADV_DEBUGFS
.print = batadv_v_gw_print,
#endif
.dump = batadv_v_gw_dump,
},
};
/**
* batadv_v_hardif_init() - initialize the algorithm specific fields in the
* hard-interface object
* @hard_iface: the hard-interface to initialize
*/
void batadv_v_hardif_init(struct batadv_hard_iface *hard_iface)
{
/* enable link throughput auto-detection by setting the throughput
* override to zero
*/
atomic_set(&hard_iface->bat_v.throughput_override, 0);
atomic_set(&hard_iface->bat_v.elp_interval, 500);
}
/**
* batadv_v_mesh_init() - initialize the B.A.T.M.A.N. V private resources for a
* mesh
* @bat_priv: the object representing the mesh interface to initialise
*
* Return: 0 on success or a negative error code otherwise
*/
int batadv_v_mesh_init(struct batadv_priv *bat_priv)
{
int ret = 0;
ret = batadv_v_ogm_init(bat_priv);
if (ret < 0)
return ret;
return 0;
}
/**
* batadv_v_mesh_free() - free the B.A.T.M.A.N. V private resources for a mesh
* @bat_priv: the object representing the mesh interface to free
*/
void batadv_v_mesh_free(struct batadv_priv *bat_priv)
{
batadv_v_ogm_free(bat_priv);
}
/**
* batadv_v_init() - B.A.T.M.A.N. V initialization function
*
* Description: Takes care of initializing all the subcomponents.
* It is invoked upon module load only.
*
* Return: 0 on success or a negative error code otherwise
*/
int __init batadv_v_init(void)
{
int ret;
/* B.A.T.M.A.N. V echo location protocol packet */
ret = batadv_recv_handler_register(BATADV_ELP,
batadv_v_elp_packet_recv);
if (ret < 0)
return ret;
ret = batadv_recv_handler_register(BATADV_OGM2,
batadv_v_ogm_packet_recv);
if (ret < 0)
goto elp_unregister;
ret = batadv_algo_register(&batadv_batman_v);
if (ret < 0)
goto ogm_unregister;
return ret;
ogm_unregister:
batadv_recv_handler_unregister(BATADV_OGM2);
elp_unregister:
batadv_recv_handler_unregister(BATADV_ELP);
return ret;
}