Orange Pi5 kernel

Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards

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// SPDX-License-Identifier: GPL-2.0
/* Copyright (C) 2009-2020 B.A.T.M.A.N. contributors:
*
* Marek Lindner
*/
#include "gateway_client.h"
#include "main.h"
#include <linux/atomic.h>
#include <linux/byteorder/generic.h>
#include <linux/errno.h>
#include <linux/etherdevice.h>
#include <linux/gfp.h>
#include <linux/if_ether.h>
#include <linux/if_vlan.h>
#include <linux/in.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/kernel.h>
#include <linux/kref.h>
#include <linux/list.h>
#include <linux/lockdep.h>
#include <linux/netdevice.h>
#include <linux/netlink.h>
#include <linux/rculist.h>
#include <linux/rcupdate.h>
#include <linux/seq_file.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/stddef.h>
#include <linux/udp.h>
#include <net/sock.h>
#include <uapi/linux/batadv_packet.h>
#include <uapi/linux/batman_adv.h>
#include "hard-interface.h"
#include "log.h"
#include "netlink.h"
#include "originator.h"
#include "routing.h"
#include "soft-interface.h"
#include "translation-table.h"
/* These are the offsets of the "hw type" and "hw address length" in the dhcp
* packet starting at the beginning of the dhcp header
*/
#define BATADV_DHCP_HTYPE_OFFSET 1
#define BATADV_DHCP_HLEN_OFFSET 2
/* Value of htype representing Ethernet */
#define BATADV_DHCP_HTYPE_ETHERNET 0x01
/* This is the offset of the "chaddr" field in the dhcp packet starting at the
* beginning of the dhcp header
*/
#define BATADV_DHCP_CHADDR_OFFSET 28
/**
* batadv_gw_node_release() - release gw_node from lists and queue for free
* after rcu grace period
* @ref: kref pointer of the gw_node
*/
void batadv_gw_node_release(struct kref *ref)
{
<------>struct batadv_gw_node *gw_node;
<------>gw_node = container_of(ref, struct batadv_gw_node, refcount);
<------>batadv_orig_node_put(gw_node->orig_node);
<------>kfree_rcu(gw_node, rcu);
}
/**
* batadv_gw_get_selected_gw_node() - Get currently selected gateway
* @bat_priv: the bat priv with all the soft interface information
*
* Return: selected gateway (with increased refcnt), NULL on errors
*/
struct batadv_gw_node *
batadv_gw_get_selected_gw_node(struct batadv_priv *bat_priv)
{
<------>struct batadv_gw_node *gw_node;
<------>rcu_read_lock();
<------>gw_node = rcu_dereference(bat_priv->gw.curr_gw);
<------>if (!gw_node)
<------><------>goto out;
<------>if (!kref_get_unless_zero(&gw_node->refcount))
<------><------>gw_node = NULL;
out:
<------>rcu_read_unlock();
<------>return gw_node;
}
/**
* batadv_gw_get_selected_orig() - Get originator of currently selected gateway
* @bat_priv: the bat priv with all the soft interface information
*
* Return: orig_node of selected gateway (with increased refcnt), NULL on errors
*/
struct batadv_orig_node *
batadv_gw_get_selected_orig(struct batadv_priv *bat_priv)
{
<------>struct batadv_gw_node *gw_node;
<------>struct batadv_orig_node *orig_node = NULL;
<------>gw_node = batadv_gw_get_selected_gw_node(bat_priv);
<------>if (!gw_node)
<------><------>goto out;
<------>rcu_read_lock();
<------>orig_node = gw_node->orig_node;
<------>if (!orig_node)
<------><------>goto unlock;
<------>if (!kref_get_unless_zero(&orig_node->refcount))
<------><------>orig_node = NULL;
unlock:
<------>rcu_read_unlock();
out:
<------>if (gw_node)
<------><------>batadv_gw_node_put(gw_node);
<------>return orig_node;
}
static void batadv_gw_select(struct batadv_priv *bat_priv,
<------><------><------> struct batadv_gw_node *new_gw_node)
{
<------>struct batadv_gw_node *curr_gw_node;
<------>spin_lock_bh(&bat_priv->gw.list_lock);
<------>if (new_gw_node)
<------><------>kref_get(&new_gw_node->refcount);
<------>curr_gw_node = rcu_replace_pointer(bat_priv->gw.curr_gw, new_gw_node,
<------><------><------><------><------> true);
<------>if (curr_gw_node)
<------><------>batadv_gw_node_put(curr_gw_node);
<------>spin_unlock_bh(&bat_priv->gw.list_lock);
}
/**
* batadv_gw_reselect() - force a gateway reselection
* @bat_priv: the bat priv with all the soft interface information
*
* Set a flag to remind the GW component to perform a new gateway reselection.
* However this function does not ensure that the current gateway is going to be
* deselected. The reselection mechanism may elect the same gateway once again.
*
* This means that invoking batadv_gw_reselect() does not guarantee a gateway
* change and therefore a uevent is not necessarily expected.
*/
void batadv_gw_reselect(struct batadv_priv *bat_priv)
{
<------>atomic_set(&bat_priv->gw.reselect, 1);
}
/**
* batadv_gw_check_client_stop() - check if client mode has been switched off
* @bat_priv: the bat priv with all the soft interface information
*
* This function assumes the caller has checked that the gw state *is actually
* changing*. This function is not supposed to be called when there is no state
* change.
*/
void batadv_gw_check_client_stop(struct batadv_priv *bat_priv)
{
<------>struct batadv_gw_node *curr_gw;
<------>if (atomic_read(&bat_priv->gw.mode) != BATADV_GW_MODE_CLIENT)
<------><------>return;
<------>curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
<------>if (!curr_gw)
<------><------>return;
<------>/* deselect the current gateway so that next time that client mode is
<------> * enabled a proper GW_ADD event can be sent
<------> */
<------>batadv_gw_select(bat_priv, NULL);
<------>/* if batman-adv is switching the gw client mode off and a gateway was
<------> * already selected, send a DEL uevent
<------> */
<------>batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_DEL, NULL);
<------>batadv_gw_node_put(curr_gw);
}
/**
* batadv_gw_election() - Elect the best gateway
* @bat_priv: the bat priv with all the soft interface information
*/
void batadv_gw_election(struct batadv_priv *bat_priv)
{
<------>struct batadv_gw_node *curr_gw = NULL;
<------>struct batadv_gw_node *next_gw = NULL;
<------>struct batadv_neigh_node *router = NULL;
<------>struct batadv_neigh_ifinfo *router_ifinfo = NULL;
<------>char gw_addr[18] = { '\0' };
<------>if (atomic_read(&bat_priv->gw.mode) != BATADV_GW_MODE_CLIENT)
<------><------>goto out;
<------>if (!bat_priv->algo_ops->gw.get_best_gw_node)
<------><------>goto out;
<------>curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
<------>if (!batadv_atomic_dec_not_zero(&bat_priv->gw.reselect) && curr_gw)
<------><------>goto out;
<------>/* if gw.reselect is set to 1 it means that a previous call to
<------> * gw.is_eligible() said that we have a new best GW, therefore it can
<------> * now be picked from the list and selected
<------> */
<------>next_gw = bat_priv->algo_ops->gw.get_best_gw_node(bat_priv);
<------>if (curr_gw == next_gw)
<------><------>goto out;
<------>if (next_gw) {
<------><------>sprintf(gw_addr, "%pM", next_gw->orig_node->orig);
<------><------>router = batadv_orig_router_get(next_gw->orig_node,
<------><------><------><------><------><------>BATADV_IF_DEFAULT);
<------><------>if (!router) {
<------><------><------>batadv_gw_reselect(bat_priv);
<------><------><------>goto out;
<------><------>}
<------><------>router_ifinfo = batadv_neigh_ifinfo_get(router,
<------><------><------><------><------><------><------>BATADV_IF_DEFAULT);
<------><------>if (!router_ifinfo) {
<------><------><------>batadv_gw_reselect(bat_priv);
<------><------><------>goto out;
<------><------>}
<------>}
<------>if (curr_gw && !next_gw) {
<------><------>batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
<------><------><------> "Removing selected gateway - no gateway in range\n");
<------><------>batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_DEL,
<------><------><------><------> NULL);
<------>} else if (!curr_gw && next_gw) {
<------><------>batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
<------><------><------> "Adding route to gateway %pM (bandwidth: %u.%u/%u.%u MBit, tq: %i)\n",
<------><------><------> next_gw->orig_node->orig,
<------><------><------> next_gw->bandwidth_down / 10,
<------><------><------> next_gw->bandwidth_down % 10,
<------><------><------> next_gw->bandwidth_up / 10,
<------><------><------> next_gw->bandwidth_up % 10,
<------><------><------> router_ifinfo->bat_iv.tq_avg);
<------><------>batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_ADD,
<------><------><------><------> gw_addr);
<------>} else {
<------><------>batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
<------><------><------> "Changing route to gateway %pM (bandwidth: %u.%u/%u.%u MBit, tq: %i)\n",
<------><------><------> next_gw->orig_node->orig,
<------><------><------> next_gw->bandwidth_down / 10,
<------><------><------> next_gw->bandwidth_down % 10,
<------><------><------> next_gw->bandwidth_up / 10,
<------><------><------> next_gw->bandwidth_up % 10,
<------><------><------> router_ifinfo->bat_iv.tq_avg);
<------><------>batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_CHANGE,
<------><------><------><------> gw_addr);
<------>}
<------>batadv_gw_select(bat_priv, next_gw);
out:
<------>if (curr_gw)
<------><------>batadv_gw_node_put(curr_gw);
<------>if (next_gw)
<------><------>batadv_gw_node_put(next_gw);
<------>if (router)
<------><------>batadv_neigh_node_put(router);
<------>if (router_ifinfo)
<------><------>batadv_neigh_ifinfo_put(router_ifinfo);
}
/**
* batadv_gw_check_election() - Elect orig node as best gateway when eligible
* @bat_priv: the bat priv with all the soft interface information
* @orig_node: orig node which is to be checked
*/
void batadv_gw_check_election(struct batadv_priv *bat_priv,
<------><------><------> struct batadv_orig_node *orig_node)
{
<------>struct batadv_orig_node *curr_gw_orig;
<------>/* abort immediately if the routing algorithm does not support gateway
<------> * election
<------> */
<------>if (!bat_priv->algo_ops->gw.is_eligible)
<------><------>return;
<------>curr_gw_orig = batadv_gw_get_selected_orig(bat_priv);
<------>if (!curr_gw_orig)
<------><------>goto reselect;
<------>/* this node already is the gateway */
<------>if (curr_gw_orig == orig_node)
<------><------>goto out;
<------>if (!bat_priv->algo_ops->gw.is_eligible(bat_priv, curr_gw_orig,
<------><------><------><------><------><------>orig_node))
<------><------>goto out;
reselect:
<------>batadv_gw_reselect(bat_priv);
out:
<------>if (curr_gw_orig)
<------><------>batadv_orig_node_put(curr_gw_orig);
}
/**
* batadv_gw_node_add() - add gateway node to list of available gateways
* @bat_priv: the bat priv with all the soft interface information
* @orig_node: originator announcing gateway capabilities
* @gateway: announced bandwidth information
*
* Has to be called with the appropriate locks being acquired
* (gw.list_lock).
*/
static void batadv_gw_node_add(struct batadv_priv *bat_priv,
<------><------><------> struct batadv_orig_node *orig_node,
<------><------><------> struct batadv_tvlv_gateway_data *gateway)
{
<------>struct batadv_gw_node *gw_node;
<------>lockdep_assert_held(&bat_priv->gw.list_lock);
<------>if (gateway->bandwidth_down == 0)
<------><------>return;
<------>gw_node = kzalloc(sizeof(*gw_node), GFP_ATOMIC);
<------>if (!gw_node)
<------><------>return;
<------>kref_init(&gw_node->refcount);
<------>INIT_HLIST_NODE(&gw_node->list);
<------>kref_get(&orig_node->refcount);
<------>gw_node->orig_node = orig_node;
<------>gw_node->bandwidth_down = ntohl(gateway->bandwidth_down);
<------>gw_node->bandwidth_up = ntohl(gateway->bandwidth_up);
<------>kref_get(&gw_node->refcount);
<------>hlist_add_head_rcu(&gw_node->list, &bat_priv->gw.gateway_list);
<------>bat_priv->gw.generation++;
<------>batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
<------><------> "Found new gateway %pM -> gw bandwidth: %u.%u/%u.%u MBit\n",
<------><------> orig_node->orig,
<------><------> ntohl(gateway->bandwidth_down) / 10,
<------><------> ntohl(gateway->bandwidth_down) % 10,
<------><------> ntohl(gateway->bandwidth_up) / 10,
<------><------> ntohl(gateway->bandwidth_up) % 10);
<------>/* don't return reference to new gw_node */
<------>batadv_gw_node_put(gw_node);
}
/**
* batadv_gw_node_get() - retrieve gateway node from list of available gateways
* @bat_priv: the bat priv with all the soft interface information
* @orig_node: originator announcing gateway capabilities
*
* Return: gateway node if found or NULL otherwise.
*/
struct batadv_gw_node *batadv_gw_node_get(struct batadv_priv *bat_priv,
<------><------><------><------><------> struct batadv_orig_node *orig_node)
{
<------>struct batadv_gw_node *gw_node_tmp, *gw_node = NULL;
<------>rcu_read_lock();
<------>hlist_for_each_entry_rcu(gw_node_tmp, &bat_priv->gw.gateway_list,
<------><------><------><------> list) {
<------><------>if (gw_node_tmp->orig_node != orig_node)
<------><------><------>continue;
<------><------>if (!kref_get_unless_zero(&gw_node_tmp->refcount))
<------><------><------>continue;
<------><------>gw_node = gw_node_tmp;
<------><------>break;
<------>}
<------>rcu_read_unlock();
<------>return gw_node;
}
/**
* batadv_gw_node_update() - update list of available gateways with changed
* bandwidth information
* @bat_priv: the bat priv with all the soft interface information
* @orig_node: originator announcing gateway capabilities
* @gateway: announced bandwidth information
*/
void batadv_gw_node_update(struct batadv_priv *bat_priv,
<------><------><------> struct batadv_orig_node *orig_node,
<------><------><------> struct batadv_tvlv_gateway_data *gateway)
{
<------>struct batadv_gw_node *gw_node, *curr_gw = NULL;
<------>spin_lock_bh(&bat_priv->gw.list_lock);
<------>gw_node = batadv_gw_node_get(bat_priv, orig_node);
<------>if (!gw_node) {
<------><------>batadv_gw_node_add(bat_priv, orig_node, gateway);
<------><------>spin_unlock_bh(&bat_priv->gw.list_lock);
<------><------>goto out;
<------>}
<------>spin_unlock_bh(&bat_priv->gw.list_lock);
<------>if (gw_node->bandwidth_down == ntohl(gateway->bandwidth_down) &&
<------> gw_node->bandwidth_up == ntohl(gateway->bandwidth_up))
<------><------>goto out;
<------>batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
<------><------> "Gateway bandwidth of originator %pM changed from %u.%u/%u.%u MBit to %u.%u/%u.%u MBit\n",
<------><------> orig_node->orig,
<------><------> gw_node->bandwidth_down / 10,
<------><------> gw_node->bandwidth_down % 10,
<------><------> gw_node->bandwidth_up / 10,
<------><------> gw_node->bandwidth_up % 10,
<------><------> ntohl(gateway->bandwidth_down) / 10,
<------><------> ntohl(gateway->bandwidth_down) % 10,
<------><------> ntohl(gateway->bandwidth_up) / 10,
<------><------> ntohl(gateway->bandwidth_up) % 10);
<------>gw_node->bandwidth_down = ntohl(gateway->bandwidth_down);
<------>gw_node->bandwidth_up = ntohl(gateway->bandwidth_up);
<------>if (ntohl(gateway->bandwidth_down) == 0) {
<------><------>batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
<------><------><------> "Gateway %pM removed from gateway list\n",
<------><------><------> orig_node->orig);
<------><------>/* Note: We don't need a NULL check here, since curr_gw never
<------><------> * gets dereferenced.
<------><------> */
<------><------>spin_lock_bh(&bat_priv->gw.list_lock);
<------><------>if (!hlist_unhashed(&gw_node->list)) {
<------><------><------>hlist_del_init_rcu(&gw_node->list);
<------><------><------>batadv_gw_node_put(gw_node);
<------><------><------>bat_priv->gw.generation++;
<------><------>}
<------><------>spin_unlock_bh(&bat_priv->gw.list_lock);
<------><------>curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
<------><------>if (gw_node == curr_gw)
<------><------><------>batadv_gw_reselect(bat_priv);
<------><------>if (curr_gw)
<------><------><------>batadv_gw_node_put(curr_gw);
<------>}
out:
<------>if (gw_node)
<------><------>batadv_gw_node_put(gw_node);
}
/**
* batadv_gw_node_delete() - Remove orig_node from gateway list
* @bat_priv: the bat priv with all the soft interface information
* @orig_node: orig node which is currently in process of being removed
*/
void batadv_gw_node_delete(struct batadv_priv *bat_priv,
<------><------><------> struct batadv_orig_node *orig_node)
{
<------>struct batadv_tvlv_gateway_data gateway;
<------>gateway.bandwidth_down = 0;
<------>gateway.bandwidth_up = 0;
<------>batadv_gw_node_update(bat_priv, orig_node, &gateway);
}
/**
* batadv_gw_node_free() - Free gateway information from soft interface
* @bat_priv: the bat priv with all the soft interface information
*/
void batadv_gw_node_free(struct batadv_priv *bat_priv)
{
<------>struct batadv_gw_node *gw_node;
<------>struct hlist_node *node_tmp;
<------>spin_lock_bh(&bat_priv->gw.list_lock);
<------>hlist_for_each_entry_safe(gw_node, node_tmp,
<------><------><------><------> &bat_priv->gw.gateway_list, list) {
<------><------>hlist_del_init_rcu(&gw_node->list);
<------><------>batadv_gw_node_put(gw_node);
<------><------>bat_priv->gw.generation++;
<------>}
<------>spin_unlock_bh(&bat_priv->gw.list_lock);
}
#ifdef CONFIG_BATMAN_ADV_DEBUGFS
/**
* batadv_gw_client_seq_print_text() - Print the gateway table in a seq file
* @seq: seq file to print on
* @offset: not used
*
* Return: always 0
*/
int batadv_gw_client_seq_print_text(struct seq_file *seq, void *offset)
{
<------>struct net_device *net_dev = (struct net_device *)seq->private;
<------>struct batadv_priv *bat_priv = netdev_priv(net_dev);
<------>struct batadv_hard_iface *primary_if;
<------>primary_if = batadv_seq_print_text_primary_if_get(seq);
<------>if (!primary_if)
<------><------>return 0;
<------>seq_printf(seq, "[B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s %s)]\n",
<------><------> BATADV_SOURCE_VERSION, primary_if->net_dev->name,
<------><------> primary_if->net_dev->dev_addr, net_dev->name,
<------><------> bat_priv->algo_ops->name);
<------>batadv_hardif_put(primary_if);
<------>if (!bat_priv->algo_ops->gw.print) {
<------><------>seq_puts(seq,
<------><------><------> "No printing function for this routing protocol\n");
<------><------>return 0;
<------>}
<------>bat_priv->algo_ops->gw.print(bat_priv, seq);
<------>return 0;
}
#endif
/**
* batadv_gw_dump() - Dump gateways into a message
* @msg: Netlink message to dump into
* @cb: Control block containing additional options
*
* Return: Error code, or length of message
*/
int batadv_gw_dump(struct sk_buff *msg, struct netlink_callback *cb)
{
<------>struct batadv_hard_iface *primary_if = NULL;
<------>struct net *net = sock_net(cb->skb->sk);
<------>struct net_device *soft_iface;
<------>struct batadv_priv *bat_priv;
<------>int ifindex;
<------>int ret;
<------>ifindex = batadv_netlink_get_ifindex(cb->nlh,
<------><------><------><------><------> BATADV_ATTR_MESH_IFINDEX);
<------>if (!ifindex)
<------><------>return -EINVAL;
<------>soft_iface = dev_get_by_index(net, ifindex);
<------>if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
<------><------>ret = -ENODEV;
<------><------>goto out;
<------>}
<------>bat_priv = netdev_priv(soft_iface);
<------>primary_if = batadv_primary_if_get_selected(bat_priv);
<------>if (!primary_if || primary_if->if_status != BATADV_IF_ACTIVE) {
<------><------>ret = -ENOENT;
<------><------>goto out;
<------>}
<------>if (!bat_priv->algo_ops->gw.dump) {
<------><------>ret = -EOPNOTSUPP;
<------><------>goto out;
<------>}
<------>bat_priv->algo_ops->gw.dump(msg, cb, bat_priv);
<------>ret = msg->len;
out:
<------>if (primary_if)
<------><------>batadv_hardif_put(primary_if);
<------>if (soft_iface)
<------><------>dev_put(soft_iface);
<------>return ret;
}
/**
* batadv_gw_dhcp_recipient_get() - check if a packet is a DHCP message
* @skb: the packet to check
* @header_len: a pointer to the batman-adv header size
* @chaddr: buffer where the client address will be stored. Valid
* only if the function returns BATADV_DHCP_TO_CLIENT
*
* This function may re-allocate the data buffer of the skb passed as argument.
*
* Return:
* - BATADV_DHCP_NO if the packet is not a dhcp message or if there was an error
* while parsing it
* - BATADV_DHCP_TO_SERVER if this is a message going to the DHCP server
* - BATADV_DHCP_TO_CLIENT if this is a message going to a DHCP client
*/
enum batadv_dhcp_recipient
batadv_gw_dhcp_recipient_get(struct sk_buff *skb, unsigned int *header_len,
<------><------><------> u8 *chaddr)
{
<------>enum batadv_dhcp_recipient ret = BATADV_DHCP_NO;
<------>struct ethhdr *ethhdr;
<------>struct iphdr *iphdr;
<------>struct ipv6hdr *ipv6hdr;
<------>struct udphdr *udphdr;
<------>struct vlan_ethhdr *vhdr;
<------>int chaddr_offset;
<------>__be16 proto;
<------>u8 *p;
<------>/* check for ethernet header */
<------>if (!pskb_may_pull(skb, *header_len + ETH_HLEN))
<------><------>return BATADV_DHCP_NO;
<------>ethhdr = eth_hdr(skb);
<------>proto = ethhdr->h_proto;
<------>*header_len += ETH_HLEN;
<------>/* check for initial vlan header */
<------>if (proto == htons(ETH_P_8021Q)) {
<------><------>if (!pskb_may_pull(skb, *header_len + VLAN_HLEN))
<------><------><------>return BATADV_DHCP_NO;
<------><------>vhdr = vlan_eth_hdr(skb);
<------><------>proto = vhdr->h_vlan_encapsulated_proto;
<------><------>*header_len += VLAN_HLEN;
<------>}
<------>/* check for ip header */
<------>switch (proto) {
<------>case htons(ETH_P_IP):
<------><------>if (!pskb_may_pull(skb, *header_len + sizeof(*iphdr)))
<------><------><------>return BATADV_DHCP_NO;
<------><------>iphdr = (struct iphdr *)(skb->data + *header_len);
<------><------>*header_len += iphdr->ihl * 4;
<------><------>/* check for udp header */
<------><------>if (iphdr->protocol != IPPROTO_UDP)
<------><------><------>return BATADV_DHCP_NO;
<------><------>break;
<------>case htons(ETH_P_IPV6):
<------><------>if (!pskb_may_pull(skb, *header_len + sizeof(*ipv6hdr)))
<------><------><------>return BATADV_DHCP_NO;
<------><------>ipv6hdr = (struct ipv6hdr *)(skb->data + *header_len);
<------><------>*header_len += sizeof(*ipv6hdr);
<------><------>/* check for udp header */
<------><------>if (ipv6hdr->nexthdr != IPPROTO_UDP)
<------><------><------>return BATADV_DHCP_NO;
<------><------>break;
<------>default:
<------><------>return BATADV_DHCP_NO;
<------>}
<------>if (!pskb_may_pull(skb, *header_len + sizeof(*udphdr)))
<------><------>return BATADV_DHCP_NO;
<------>udphdr = (struct udphdr *)(skb->data + *header_len);
<------>*header_len += sizeof(*udphdr);
<------>/* check for bootp port */
<------>switch (proto) {
<------>case htons(ETH_P_IP):
<------><------>if (udphdr->dest == htons(67))
<------><------><------>ret = BATADV_DHCP_TO_SERVER;
<------><------>else if (udphdr->source == htons(67))
<------><------><------>ret = BATADV_DHCP_TO_CLIENT;
<------><------>break;
<------>case htons(ETH_P_IPV6):
<------><------>if (udphdr->dest == htons(547))
<------><------><------>ret = BATADV_DHCP_TO_SERVER;
<------><------>else if (udphdr->source == htons(547))
<------><------><------>ret = BATADV_DHCP_TO_CLIENT;
<------><------>break;
<------>}
<------>chaddr_offset = *header_len + BATADV_DHCP_CHADDR_OFFSET;
<------>/* store the client address if the message is going to a client */
<------>if (ret == BATADV_DHCP_TO_CLIENT) {
<------><------>if (!pskb_may_pull(skb, chaddr_offset + ETH_ALEN))
<------><------><------>return BATADV_DHCP_NO;
<------><------>/* check if the DHCP packet carries an Ethernet DHCP */
<------><------>p = skb->data + *header_len + BATADV_DHCP_HTYPE_OFFSET;
<------><------>if (*p != BATADV_DHCP_HTYPE_ETHERNET)
<------><------><------>return BATADV_DHCP_NO;
<------><------>/* check if the DHCP packet carries a valid Ethernet address */
<------><------>p = skb->data + *header_len + BATADV_DHCP_HLEN_OFFSET;
<------><------>if (*p != ETH_ALEN)
<------><------><------>return BATADV_DHCP_NO;
<------><------>ether_addr_copy(chaddr, skb->data + chaddr_offset);
<------>}
<------>return ret;
}
/**
* batadv_gw_out_of_range() - check if the dhcp request destination is the best
* gateway
* @bat_priv: the bat priv with all the soft interface information
* @skb: the outgoing packet
*
* Check if the skb is a DHCP request and if it is sent to the current best GW
* server. Due to topology changes it may be the case that the GW server
* previously selected is not the best one anymore.
*
* This call might reallocate skb data.
* Must be invoked only when the DHCP packet is going TO a DHCP SERVER.
*
* Return: true if the packet destination is unicast and it is not the best gw,
* false otherwise.
*/
bool batadv_gw_out_of_range(struct batadv_priv *bat_priv,
<------><------><------> struct sk_buff *skb)
{
<------>struct batadv_neigh_node *neigh_curr = NULL;
<------>struct batadv_neigh_node *neigh_old = NULL;
<------>struct batadv_orig_node *orig_dst_node = NULL;
<------>struct batadv_gw_node *gw_node = NULL;
<------>struct batadv_gw_node *curr_gw = NULL;
<------>struct batadv_neigh_ifinfo *curr_ifinfo, *old_ifinfo;
<------>struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
<------>bool out_of_range = false;
<------>u8 curr_tq_avg;
<------>unsigned short vid;
<------>vid = batadv_get_vid(skb, 0);
<------>if (is_multicast_ether_addr(ethhdr->h_dest))
<------><------>goto out;
<------>orig_dst_node = batadv_transtable_search(bat_priv, ethhdr->h_source,
<------><------><------><------><------><------> ethhdr->h_dest, vid);
<------>if (!orig_dst_node)
<------><------>goto out;
<------>gw_node = batadv_gw_node_get(bat_priv, orig_dst_node);
<------>if (!gw_node)
<------><------>goto out;
<------>switch (atomic_read(&bat_priv->gw.mode)) {
<------>case BATADV_GW_MODE_SERVER:
<------><------>/* If we are a GW then we are our best GW. We can artificially
<------><------> * set the tq towards ourself as the maximum value
<------><------> */
<------><------>curr_tq_avg = BATADV_TQ_MAX_VALUE;
<------><------>break;
<------>case BATADV_GW_MODE_CLIENT:
<------><------>curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
<------><------>if (!curr_gw)
<------><------><------>goto out;
<------><------>/* packet is going to our gateway */
<------><------>if (curr_gw->orig_node == orig_dst_node)
<------><------><------>goto out;
<------><------>/* If the dhcp packet has been sent to a different gw,
<------><------> * we have to evaluate whether the old gw is still
<------><------> * reliable enough
<------><------> */
<------><------>neigh_curr = batadv_find_router(bat_priv, curr_gw->orig_node,
<------><------><------><------><------><------>NULL);
<------><------>if (!neigh_curr)
<------><------><------>goto out;
<------><------>curr_ifinfo = batadv_neigh_ifinfo_get(neigh_curr,
<------><------><------><------><------><------> BATADV_IF_DEFAULT);
<------><------>if (!curr_ifinfo)
<------><------><------>goto out;
<------><------>curr_tq_avg = curr_ifinfo->bat_iv.tq_avg;
<------><------>batadv_neigh_ifinfo_put(curr_ifinfo);
<------><------>break;
<------>case BATADV_GW_MODE_OFF:
<------>default:
<------><------>goto out;
<------>}
<------>neigh_old = batadv_find_router(bat_priv, orig_dst_node, NULL);
<------>if (!neigh_old)
<------><------>goto out;
<------>old_ifinfo = batadv_neigh_ifinfo_get(neigh_old, BATADV_IF_DEFAULT);
<------>if (!old_ifinfo)
<------><------>goto out;
<------>if ((curr_tq_avg - old_ifinfo->bat_iv.tq_avg) > BATADV_GW_THRESHOLD)
<------><------>out_of_range = true;
<------>batadv_neigh_ifinfo_put(old_ifinfo);
out:
<------>if (orig_dst_node)
<------><------>batadv_orig_node_put(orig_dst_node);
<------>if (curr_gw)
<------><------>batadv_gw_node_put(curr_gw);
<------>if (gw_node)
<------><------>batadv_gw_node_put(gw_node);
<------>if (neigh_old)
<------><------>batadv_neigh_node_put(neigh_old);
<------>if (neigh_curr)
<------><------>batadv_neigh_node_put(neigh_curr);
<------>return out_of_range;
}