// SPDX-License-Identifier: GPL-2.0-only
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/* Cluster IP hashmark target
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* (C) 2003-2004 by Harald Welte <laforge@netfilter.org>
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* based on ideas of Fabio Olive Leite <olive@unixforge.org>
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*
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* Development of this code funded by SuSE Linux AG, https://www.suse.com/
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/module.h>
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#include <linux/proc_fs.h>
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#include <linux/jhash.h>
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#include <linux/bitops.h>
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#include <linux/skbuff.h>
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#include <linux/slab.h>
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#include <linux/ip.h>
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#include <linux/tcp.h>
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#include <linux/udp.h>
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#include <linux/icmp.h>
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#include <linux/if_arp.h>
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#include <linux/seq_file.h>
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#include <linux/refcount.h>
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#include <linux/netfilter_arp.h>
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#include <linux/netfilter/x_tables.h>
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#include <linux/netfilter_ipv4/ip_tables.h>
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#include <linux/netfilter_ipv4/ipt_CLUSTERIP.h>
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#include <net/netfilter/nf_conntrack.h>
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#include <net/net_namespace.h>
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#include <net/netns/generic.h>
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#include <net/checksum.h>
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#include <net/ip.h>
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#define CLUSTERIP_VERSION "0.8"
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|
MODULE_LICENSE("GPL");
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MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
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MODULE_DESCRIPTION("Xtables: CLUSTERIP target");
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|
struct clusterip_config {
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struct list_head list; /* list of all configs */
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refcount_t refcount; /* reference count */
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refcount_t entries; /* number of entries/rules
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* referencing us */
|
|
__be32 clusterip; /* the IP address */
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u_int8_t clustermac[ETH_ALEN]; /* the MAC address */
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int ifindex; /* device ifindex */
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u_int16_t num_total_nodes; /* total number of nodes */
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unsigned long local_nodes; /* node number array */
|
|
#ifdef CONFIG_PROC_FS
|
struct proc_dir_entry *pde; /* proc dir entry */
|
#endif
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enum clusterip_hashmode hash_mode; /* which hashing mode */
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u_int32_t hash_initval; /* hash initialization */
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struct rcu_head rcu; /* for call_rcu */
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struct net *net; /* netns for pernet list */
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char ifname[IFNAMSIZ]; /* device ifname */
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};
|
|
#ifdef CONFIG_PROC_FS
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static const struct proc_ops clusterip_proc_ops;
|
#endif
|
|
struct clusterip_net {
|
struct list_head configs;
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/* lock protects the configs list */
|
spinlock_t lock;
|
|
#ifdef CONFIG_PROC_FS
|
struct proc_dir_entry *procdir;
|
/* mutex protects the config->pde*/
|
struct mutex mutex;
|
#endif
|
};
|
|
static unsigned int clusterip_net_id __read_mostly;
|
static inline struct clusterip_net *clusterip_pernet(struct net *net)
|
{
|
return net_generic(net, clusterip_net_id);
|
}
|
|
static inline void
|
clusterip_config_get(struct clusterip_config *c)
|
{
|
refcount_inc(&c->refcount);
|
}
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|
static void clusterip_config_rcu_free(struct rcu_head *head)
|
{
|
struct clusterip_config *config;
|
struct net_device *dev;
|
|
config = container_of(head, struct clusterip_config, rcu);
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dev = dev_get_by_name(config->net, config->ifname);
|
if (dev) {
|
dev_mc_del(dev, config->clustermac);
|
dev_put(dev);
|
}
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kfree(config);
|
}
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static inline void
|
clusterip_config_put(struct clusterip_config *c)
|
{
|
if (refcount_dec_and_test(&c->refcount))
|
call_rcu(&c->rcu, clusterip_config_rcu_free);
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}
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|
/* decrease the count of entries using/referencing this config. If last
|
* entry(rule) is removed, remove the config from lists, but don't free it
|
* yet, since proc-files could still be holding references */
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static inline void
|
clusterip_config_entry_put(struct clusterip_config *c)
|
{
|
struct clusterip_net *cn = clusterip_pernet(c->net);
|
|
local_bh_disable();
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if (refcount_dec_and_lock(&c->entries, &cn->lock)) {
|
list_del_rcu(&c->list);
|
spin_unlock(&cn->lock);
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local_bh_enable();
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/* In case anyone still accesses the file, the open/close
|
* functions are also incrementing the refcount on their own,
|
* so it's safe to remove the entry even if it's in use. */
|
#ifdef CONFIG_PROC_FS
|
mutex_lock(&cn->mutex);
|
if (cn->procdir)
|
proc_remove(c->pde);
|
mutex_unlock(&cn->mutex);
|
#endif
|
return;
|
}
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local_bh_enable();
|
}
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|
static struct clusterip_config *
|
__clusterip_config_find(struct net *net, __be32 clusterip)
|
{
|
struct clusterip_config *c;
|
struct clusterip_net *cn = clusterip_pernet(net);
|
|
list_for_each_entry_rcu(c, &cn->configs, list) {
|
if (c->clusterip == clusterip)
|
return c;
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}
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|
return NULL;
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}
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static inline struct clusterip_config *
|
clusterip_config_find_get(struct net *net, __be32 clusterip, int entry)
|
{
|
struct clusterip_config *c;
|
|
rcu_read_lock_bh();
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c = __clusterip_config_find(net, clusterip);
|
if (c) {
|
#ifdef CONFIG_PROC_FS
|
if (!c->pde)
|
c = NULL;
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else
|
#endif
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if (unlikely(!refcount_inc_not_zero(&c->refcount)))
|
c = NULL;
|
else if (entry) {
|
if (unlikely(!refcount_inc_not_zero(&c->entries))) {
|
clusterip_config_put(c);
|
c = NULL;
|
}
|
}
|
}
|
rcu_read_unlock_bh();
|
|
return c;
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}
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|
static void
|
clusterip_config_init_nodelist(struct clusterip_config *c,
|
const struct ipt_clusterip_tgt_info *i)
|
{
|
int n;
|
|
for (n = 0; n < i->num_local_nodes; n++)
|
set_bit(i->local_nodes[n] - 1, &c->local_nodes);
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}
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static int
|
clusterip_netdev_event(struct notifier_block *this, unsigned long event,
|
void *ptr)
|
{
|
struct net_device *dev = netdev_notifier_info_to_dev(ptr);
|
struct net *net = dev_net(dev);
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struct clusterip_net *cn = clusterip_pernet(net);
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struct clusterip_config *c;
|
|
spin_lock_bh(&cn->lock);
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list_for_each_entry_rcu(c, &cn->configs, list) {
|
switch (event) {
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case NETDEV_REGISTER:
|
if (!strcmp(dev->name, c->ifname)) {
|
c->ifindex = dev->ifindex;
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dev_mc_add(dev, c->clustermac);
|
}
|
break;
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case NETDEV_UNREGISTER:
|
if (dev->ifindex == c->ifindex) {
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dev_mc_del(dev, c->clustermac);
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c->ifindex = -1;
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}
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break;
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case NETDEV_CHANGENAME:
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if (!strcmp(dev->name, c->ifname)) {
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c->ifindex = dev->ifindex;
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dev_mc_add(dev, c->clustermac);
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} else if (dev->ifindex == c->ifindex) {
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dev_mc_del(dev, c->clustermac);
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c->ifindex = -1;
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}
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break;
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}
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}
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spin_unlock_bh(&cn->lock);
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return NOTIFY_DONE;
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}
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static struct clusterip_config *
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clusterip_config_init(struct net *net, const struct ipt_clusterip_tgt_info *i,
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__be32 ip, const char *iniface)
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{
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struct clusterip_net *cn = clusterip_pernet(net);
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struct clusterip_config *c;
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struct net_device *dev;
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int err;
|
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if (iniface[0] == '\0') {
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pr_info("Please specify an interface name\n");
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return ERR_PTR(-EINVAL);
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}
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c = kzalloc(sizeof(*c), GFP_ATOMIC);
|
if (!c)
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return ERR_PTR(-ENOMEM);
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dev = dev_get_by_name(net, iniface);
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if (!dev) {
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pr_info("no such interface %s\n", iniface);
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kfree(c);
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return ERR_PTR(-ENOENT);
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}
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c->ifindex = dev->ifindex;
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strcpy(c->ifname, dev->name);
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memcpy(&c->clustermac, &i->clustermac, ETH_ALEN);
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dev_mc_add(dev, c->clustermac);
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dev_put(dev);
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c->clusterip = ip;
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c->num_total_nodes = i->num_total_nodes;
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clusterip_config_init_nodelist(c, i);
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c->hash_mode = i->hash_mode;
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c->hash_initval = i->hash_initval;
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c->net = net;
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refcount_set(&c->refcount, 1);
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|
spin_lock_bh(&cn->lock);
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if (__clusterip_config_find(net, ip)) {
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err = -EBUSY;
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goto out_config_put;
|
}
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list_add_rcu(&c->list, &cn->configs);
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spin_unlock_bh(&cn->lock);
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#ifdef CONFIG_PROC_FS
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{
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char buffer[16];
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/* create proc dir entry */
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sprintf(buffer, "%pI4", &ip);
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mutex_lock(&cn->mutex);
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c->pde = proc_create_data(buffer, 0600,
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cn->procdir,
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&clusterip_proc_ops, c);
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mutex_unlock(&cn->mutex);
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if (!c->pde) {
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err = -ENOMEM;
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goto err;
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}
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}
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#endif
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refcount_set(&c->entries, 1);
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return c;
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#ifdef CONFIG_PROC_FS
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err:
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#endif
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spin_lock_bh(&cn->lock);
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list_del_rcu(&c->list);
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out_config_put:
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spin_unlock_bh(&cn->lock);
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clusterip_config_put(c);
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return ERR_PTR(err);
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}
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#ifdef CONFIG_PROC_FS
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static int
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clusterip_add_node(struct clusterip_config *c, u_int16_t nodenum)
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{
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if (nodenum == 0 ||
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nodenum > c->num_total_nodes)
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return 1;
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/* check if we already have this number in our bitfield */
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if (test_and_set_bit(nodenum - 1, &c->local_nodes))
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return 1;
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return 0;
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}
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static bool
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clusterip_del_node(struct clusterip_config *c, u_int16_t nodenum)
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{
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if (nodenum == 0 ||
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nodenum > c->num_total_nodes)
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return true;
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if (test_and_clear_bit(nodenum - 1, &c->local_nodes))
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return false;
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return true;
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}
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#endif
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static inline u_int32_t
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clusterip_hashfn(const struct sk_buff *skb,
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const struct clusterip_config *config)
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{
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const struct iphdr *iph = ip_hdr(skb);
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unsigned long hashval;
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u_int16_t sport = 0, dport = 0;
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int poff;
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poff = proto_ports_offset(iph->protocol);
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if (poff >= 0) {
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const u_int16_t *ports;
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u16 _ports[2];
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ports = skb_header_pointer(skb, iph->ihl * 4 + poff, 4, _ports);
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if (ports) {
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sport = ports[0];
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dport = ports[1];
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}
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} else {
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net_info_ratelimited("unknown protocol %u\n", iph->protocol);
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}
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switch (config->hash_mode) {
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case CLUSTERIP_HASHMODE_SIP:
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hashval = jhash_1word(ntohl(iph->saddr),
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config->hash_initval);
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break;
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case CLUSTERIP_HASHMODE_SIP_SPT:
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hashval = jhash_2words(ntohl(iph->saddr), sport,
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config->hash_initval);
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break;
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case CLUSTERIP_HASHMODE_SIP_SPT_DPT:
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hashval = jhash_3words(ntohl(iph->saddr), sport, dport,
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config->hash_initval);
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break;
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default:
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/* to make gcc happy */
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hashval = 0;
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/* This cannot happen, unless the check function wasn't called
|
* at rule load time */
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pr_info("unknown mode %u\n", config->hash_mode);
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BUG();
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break;
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}
|
|
/* node numbers are 1..n, not 0..n */
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return reciprocal_scale(hashval, config->num_total_nodes) + 1;
|
}
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static inline int
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clusterip_responsible(const struct clusterip_config *config, u_int32_t hash)
|
{
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return test_bit(hash - 1, &config->local_nodes);
|
}
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/***********************************************************************
|
* IPTABLES TARGET
|
***********************************************************************/
|
|
static unsigned int
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clusterip_tg(struct sk_buff *skb, const struct xt_action_param *par)
|
{
|
const struct ipt_clusterip_tgt_info *cipinfo = par->targinfo;
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struct nf_conn *ct;
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enum ip_conntrack_info ctinfo;
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u_int32_t hash;
|
|
/* don't need to clusterip_config_get() here, since refcount
|
* is only decremented by destroy() - and ip_tables guarantees
|
* that the ->target() function isn't called after ->destroy() */
|
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ct = nf_ct_get(skb, &ctinfo);
|
if (ct == NULL)
|
return NF_DROP;
|
|
/* special case: ICMP error handling. conntrack distinguishes between
|
* error messages (RELATED) and information requests (see below) */
|
if (ip_hdr(skb)->protocol == IPPROTO_ICMP &&
|
(ctinfo == IP_CT_RELATED ||
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ctinfo == IP_CT_RELATED_REPLY))
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return XT_CONTINUE;
|
|
/* nf_conntrack_proto_icmp guarantees us that we only have ICMP_ECHO,
|
* TIMESTAMP, INFO_REQUEST or ICMP_ADDRESS type icmp packets from here
|
* on, which all have an ID field [relevant for hashing]. */
|
|
hash = clusterip_hashfn(skb, cipinfo->config);
|
|
switch (ctinfo) {
|
case IP_CT_NEW:
|
WRITE_ONCE(ct->mark, hash);
|
break;
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case IP_CT_RELATED:
|
case IP_CT_RELATED_REPLY:
|
/* FIXME: we don't handle expectations at the moment.
|
* They can arrive on a different node than
|
* the master connection (e.g. FTP passive mode) */
|
case IP_CT_ESTABLISHED:
|
case IP_CT_ESTABLISHED_REPLY:
|
break;
|
default: /* Prevent gcc warnings */
|
break;
|
}
|
|
#ifdef DEBUG
|
nf_ct_dump_tuple_ip(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
|
#endif
|
pr_debug("hash=%u ct_hash=%u ", hash, READ_ONCE(ct->mark));
|
if (!clusterip_responsible(cipinfo->config, hash)) {
|
pr_debug("not responsible\n");
|
return NF_DROP;
|
}
|
pr_debug("responsible\n");
|
|
/* despite being received via linklayer multicast, this is
|
* actually a unicast IP packet. TCP doesn't like PACKET_MULTICAST */
|
skb->pkt_type = PACKET_HOST;
|
|
return XT_CONTINUE;
|
}
|
|
static int clusterip_tg_check(const struct xt_tgchk_param *par)
|
{
|
struct ipt_clusterip_tgt_info *cipinfo = par->targinfo;
|
const struct ipt_entry *e = par->entryinfo;
|
struct clusterip_config *config;
|
int ret, i;
|
|
if (par->nft_compat) {
|
pr_err("cannot use CLUSTERIP target from nftables compat\n");
|
return -EOPNOTSUPP;
|
}
|
|
if (cipinfo->hash_mode != CLUSTERIP_HASHMODE_SIP &&
|
cipinfo->hash_mode != CLUSTERIP_HASHMODE_SIP_SPT &&
|
cipinfo->hash_mode != CLUSTERIP_HASHMODE_SIP_SPT_DPT) {
|
pr_info("unknown mode %u\n", cipinfo->hash_mode);
|
return -EINVAL;
|
|
}
|
if (e->ip.dmsk.s_addr != htonl(0xffffffff) ||
|
e->ip.dst.s_addr == 0) {
|
pr_info("Please specify destination IP\n");
|
return -EINVAL;
|
}
|
if (cipinfo->num_local_nodes > ARRAY_SIZE(cipinfo->local_nodes)) {
|
pr_info("bad num_local_nodes %u\n", cipinfo->num_local_nodes);
|
return -EINVAL;
|
}
|
for (i = 0; i < cipinfo->num_local_nodes; i++) {
|
if (cipinfo->local_nodes[i] - 1 >=
|
sizeof(config->local_nodes) * 8) {
|
pr_info("bad local_nodes[%d] %u\n",
|
i, cipinfo->local_nodes[i]);
|
return -EINVAL;
|
}
|
}
|
|
config = clusterip_config_find_get(par->net, e->ip.dst.s_addr, 1);
|
if (!config) {
|
if (!(cipinfo->flags & CLUSTERIP_FLAG_NEW)) {
|
pr_info("no config found for %pI4, need 'new'\n",
|
&e->ip.dst.s_addr);
|
return -EINVAL;
|
} else {
|
config = clusterip_config_init(par->net, cipinfo,
|
e->ip.dst.s_addr,
|
e->ip.iniface);
|
if (IS_ERR(config))
|
return PTR_ERR(config);
|
}
|
} else if (memcmp(&config->clustermac, &cipinfo->clustermac, ETH_ALEN)) {
|
clusterip_config_entry_put(config);
|
clusterip_config_put(config);
|
return -EINVAL;
|
}
|
|
ret = nf_ct_netns_get(par->net, par->family);
|
if (ret < 0) {
|
pr_info("cannot load conntrack support for proto=%u\n",
|
par->family);
|
clusterip_config_entry_put(config);
|
clusterip_config_put(config);
|
return ret;
|
}
|
|
if (!par->net->xt.clusterip_deprecated_warning) {
|
pr_info("ipt_CLUSTERIP is deprecated and it will removed soon, "
|
"use xt_cluster instead\n");
|
par->net->xt.clusterip_deprecated_warning = true;
|
}
|
|
cipinfo->config = config;
|
return ret;
|
}
|
|
/* drop reference count of cluster config when rule is deleted */
|
static void clusterip_tg_destroy(const struct xt_tgdtor_param *par)
|
{
|
const struct ipt_clusterip_tgt_info *cipinfo = par->targinfo;
|
|
/* if no more entries are referencing the config, remove it
|
* from the list and destroy the proc entry */
|
clusterip_config_entry_put(cipinfo->config);
|
|
clusterip_config_put(cipinfo->config);
|
|
nf_ct_netns_put(par->net, par->family);
|
}
|
|
#ifdef CONFIG_COMPAT
|
struct compat_ipt_clusterip_tgt_info
|
{
|
u_int32_t flags;
|
u_int8_t clustermac[6];
|
u_int16_t num_total_nodes;
|
u_int16_t num_local_nodes;
|
u_int16_t local_nodes[CLUSTERIP_MAX_NODES];
|
u_int32_t hash_mode;
|
u_int32_t hash_initval;
|
compat_uptr_t config;
|
};
|
#endif /* CONFIG_COMPAT */
|
|
static struct xt_target clusterip_tg_reg __read_mostly = {
|
.name = "CLUSTERIP",
|
.family = NFPROTO_IPV4,
|
.target = clusterip_tg,
|
.checkentry = clusterip_tg_check,
|
.destroy = clusterip_tg_destroy,
|
.targetsize = sizeof(struct ipt_clusterip_tgt_info),
|
.usersize = offsetof(struct ipt_clusterip_tgt_info, config),
|
#ifdef CONFIG_COMPAT
|
.compatsize = sizeof(struct compat_ipt_clusterip_tgt_info),
|
#endif /* CONFIG_COMPAT */
|
.me = THIS_MODULE
|
};
|
|
|
/***********************************************************************
|
* ARP MANGLING CODE
|
***********************************************************************/
|
|
/* hardcoded for 48bit ethernet and 32bit ipv4 addresses */
|
struct arp_payload {
|
u_int8_t src_hw[ETH_ALEN];
|
__be32 src_ip;
|
u_int8_t dst_hw[ETH_ALEN];
|
__be32 dst_ip;
|
} __packed;
|
|
#ifdef DEBUG
|
static void arp_print(struct arp_payload *payload)
|
{
|
#define HBUFFERLEN 30
|
char hbuffer[HBUFFERLEN];
|
int j, k;
|
|
for (k = 0, j = 0; k < HBUFFERLEN - 3 && j < ETH_ALEN; j++) {
|
hbuffer[k++] = hex_asc_hi(payload->src_hw[j]);
|
hbuffer[k++] = hex_asc_lo(payload->src_hw[j]);
|
hbuffer[k++] = ':';
|
}
|
hbuffer[--k] = '\0';
|
|
pr_debug("src %pI4@%s, dst %pI4\n",
|
&payload->src_ip, hbuffer, &payload->dst_ip);
|
}
|
#endif
|
|
static unsigned int
|
arp_mangle(void *priv,
|
struct sk_buff *skb,
|
const struct nf_hook_state *state)
|
{
|
struct arphdr *arp = arp_hdr(skb);
|
struct arp_payload *payload;
|
struct clusterip_config *c;
|
struct net *net = state->net;
|
|
/* we don't care about non-ethernet and non-ipv4 ARP */
|
if (arp->ar_hrd != htons(ARPHRD_ETHER) ||
|
arp->ar_pro != htons(ETH_P_IP) ||
|
arp->ar_pln != 4 || arp->ar_hln != ETH_ALEN)
|
return NF_ACCEPT;
|
|
/* we only want to mangle arp requests and replies */
|
if (arp->ar_op != htons(ARPOP_REPLY) &&
|
arp->ar_op != htons(ARPOP_REQUEST))
|
return NF_ACCEPT;
|
|
payload = (void *)(arp+1);
|
|
/* if there is no clusterip configuration for the arp reply's
|
* source ip, we don't want to mangle it */
|
c = clusterip_config_find_get(net, payload->src_ip, 0);
|
if (!c)
|
return NF_ACCEPT;
|
|
/* normally the linux kernel always replies to arp queries of
|
* addresses on different interfacs. However, in the CLUSTERIP case
|
* this wouldn't work, since we didn't subscribe the mcast group on
|
* other interfaces */
|
if (c->ifindex != state->out->ifindex) {
|
pr_debug("not mangling arp reply on different interface: cip'%d'-skb'%d'\n",
|
c->ifindex, state->out->ifindex);
|
clusterip_config_put(c);
|
return NF_ACCEPT;
|
}
|
|
/* mangle reply hardware address */
|
memcpy(payload->src_hw, c->clustermac, arp->ar_hln);
|
|
#ifdef DEBUG
|
pr_debug("mangled arp reply: ");
|
arp_print(payload);
|
#endif
|
|
clusterip_config_put(c);
|
|
return NF_ACCEPT;
|
}
|
|
static const struct nf_hook_ops cip_arp_ops = {
|
.hook = arp_mangle,
|
.pf = NFPROTO_ARP,
|
.hooknum = NF_ARP_OUT,
|
.priority = -1
|
};
|
|
/***********************************************************************
|
* PROC DIR HANDLING
|
***********************************************************************/
|
|
#ifdef CONFIG_PROC_FS
|
|
struct clusterip_seq_position {
|
unsigned int pos; /* position */
|
unsigned int weight; /* number of bits set == size */
|
unsigned int bit; /* current bit */
|
unsigned long val; /* current value */
|
};
|
|
static void *clusterip_seq_start(struct seq_file *s, loff_t *pos)
|
{
|
struct clusterip_config *c = s->private;
|
unsigned int weight;
|
u_int32_t local_nodes;
|
struct clusterip_seq_position *idx;
|
|
/* FIXME: possible race */
|
local_nodes = c->local_nodes;
|
weight = hweight32(local_nodes);
|
if (*pos >= weight)
|
return NULL;
|
|
idx = kmalloc(sizeof(struct clusterip_seq_position), GFP_KERNEL);
|
if (!idx)
|
return ERR_PTR(-ENOMEM);
|
|
idx->pos = *pos;
|
idx->weight = weight;
|
idx->bit = ffs(local_nodes);
|
idx->val = local_nodes;
|
clear_bit(idx->bit - 1, &idx->val);
|
|
return idx;
|
}
|
|
static void *clusterip_seq_next(struct seq_file *s, void *v, loff_t *pos)
|
{
|
struct clusterip_seq_position *idx = v;
|
|
*pos = ++idx->pos;
|
if (*pos >= idx->weight) {
|
kfree(v);
|
return NULL;
|
}
|
idx->bit = ffs(idx->val);
|
clear_bit(idx->bit - 1, &idx->val);
|
return idx;
|
}
|
|
static void clusterip_seq_stop(struct seq_file *s, void *v)
|
{
|
if (!IS_ERR(v))
|
kfree(v);
|
}
|
|
static int clusterip_seq_show(struct seq_file *s, void *v)
|
{
|
struct clusterip_seq_position *idx = v;
|
|
if (idx->pos != 0)
|
seq_putc(s, ',');
|
|
seq_printf(s, "%u", idx->bit);
|
|
if (idx->pos == idx->weight - 1)
|
seq_putc(s, '\n');
|
|
return 0;
|
}
|
|
static const struct seq_operations clusterip_seq_ops = {
|
.start = clusterip_seq_start,
|
.next = clusterip_seq_next,
|
.stop = clusterip_seq_stop,
|
.show = clusterip_seq_show,
|
};
|
|
static int clusterip_proc_open(struct inode *inode, struct file *file)
|
{
|
int ret = seq_open(file, &clusterip_seq_ops);
|
|
if (!ret) {
|
struct seq_file *sf = file->private_data;
|
struct clusterip_config *c = PDE_DATA(inode);
|
|
sf->private = c;
|
|
clusterip_config_get(c);
|
}
|
|
return ret;
|
}
|
|
static int clusterip_proc_release(struct inode *inode, struct file *file)
|
{
|
struct clusterip_config *c = PDE_DATA(inode);
|
int ret;
|
|
ret = seq_release(inode, file);
|
|
if (!ret)
|
clusterip_config_put(c);
|
|
return ret;
|
}
|
|
static ssize_t clusterip_proc_write(struct file *file, const char __user *input,
|
size_t size, loff_t *ofs)
|
{
|
struct clusterip_config *c = PDE_DATA(file_inode(file));
|
#define PROC_WRITELEN 10
|
char buffer[PROC_WRITELEN+1];
|
unsigned long nodenum;
|
int rc;
|
|
if (size > PROC_WRITELEN)
|
return -EIO;
|
if (copy_from_user(buffer, input, size))
|
return -EFAULT;
|
buffer[size] = 0;
|
|
if (*buffer == '+') {
|
rc = kstrtoul(buffer+1, 10, &nodenum);
|
if (rc)
|
return rc;
|
if (clusterip_add_node(c, nodenum))
|
return -ENOMEM;
|
} else if (*buffer == '-') {
|
rc = kstrtoul(buffer+1, 10, &nodenum);
|
if (rc)
|
return rc;
|
if (clusterip_del_node(c, nodenum))
|
return -ENOENT;
|
} else
|
return -EIO;
|
|
return size;
|
}
|
|
static const struct proc_ops clusterip_proc_ops = {
|
.proc_open = clusterip_proc_open,
|
.proc_read = seq_read,
|
.proc_write = clusterip_proc_write,
|
.proc_lseek = seq_lseek,
|
.proc_release = clusterip_proc_release,
|
};
|
|
#endif /* CONFIG_PROC_FS */
|
|
static int clusterip_net_init(struct net *net)
|
{
|
struct clusterip_net *cn = clusterip_pernet(net);
|
int ret;
|
|
INIT_LIST_HEAD(&cn->configs);
|
|
spin_lock_init(&cn->lock);
|
|
ret = nf_register_net_hook(net, &cip_arp_ops);
|
if (ret < 0)
|
return ret;
|
|
#ifdef CONFIG_PROC_FS
|
cn->procdir = proc_mkdir("ipt_CLUSTERIP", net->proc_net);
|
if (!cn->procdir) {
|
nf_unregister_net_hook(net, &cip_arp_ops);
|
pr_err("Unable to proc dir entry\n");
|
return -ENOMEM;
|
}
|
mutex_init(&cn->mutex);
|
#endif /* CONFIG_PROC_FS */
|
|
return 0;
|
}
|
|
static void clusterip_net_exit(struct net *net)
|
{
|
#ifdef CONFIG_PROC_FS
|
struct clusterip_net *cn = clusterip_pernet(net);
|
|
mutex_lock(&cn->mutex);
|
proc_remove(cn->procdir);
|
cn->procdir = NULL;
|
mutex_unlock(&cn->mutex);
|
#endif
|
nf_unregister_net_hook(net, &cip_arp_ops);
|
}
|
|
static struct pernet_operations clusterip_net_ops = {
|
.init = clusterip_net_init,
|
.exit = clusterip_net_exit,
|
.id = &clusterip_net_id,
|
.size = sizeof(struct clusterip_net),
|
};
|
|
static struct notifier_block cip_netdev_notifier = {
|
.notifier_call = clusterip_netdev_event
|
};
|
|
static int __init clusterip_tg_init(void)
|
{
|
int ret;
|
|
ret = register_pernet_subsys(&clusterip_net_ops);
|
if (ret < 0)
|
return ret;
|
|
ret = xt_register_target(&clusterip_tg_reg);
|
if (ret < 0)
|
goto cleanup_subsys;
|
|
ret = register_netdevice_notifier(&cip_netdev_notifier);
|
if (ret < 0)
|
goto unregister_target;
|
|
pr_info("ClusterIP Version %s loaded successfully\n",
|
CLUSTERIP_VERSION);
|
|
return 0;
|
|
unregister_target:
|
xt_unregister_target(&clusterip_tg_reg);
|
cleanup_subsys:
|
unregister_pernet_subsys(&clusterip_net_ops);
|
return ret;
|
}
|
|
static void __exit clusterip_tg_exit(void)
|
{
|
pr_info("ClusterIP Version %s unloading\n", CLUSTERIP_VERSION);
|
|
unregister_netdevice_notifier(&cip_netdev_notifier);
|
xt_unregister_target(&clusterip_tg_reg);
|
unregister_pernet_subsys(&clusterip_net_ops);
|
|
/* Wait for completion of call_rcu()'s (clusterip_config_rcu_free) */
|
rcu_barrier();
|
}
|
|
module_init(clusterip_tg_init);
|
module_exit(clusterip_tg_exit);
|
