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netfilter: ip_tables: remove clusterip target 

Marked as 'to be removed soon' since kernel 4.1 (2015).
Functionality was superseded by the 'cluster' match, added in kernel
2.6.30 (2009).

clusterip_tg_check still has races that can give

 proc_dir_entry 'ipt_CLUSTERIP/10.1.1.2' already registered

followed by a WARN splat.

Remove it instead of trying to fix this up again.
clusterip uapi header is left as-is for now.

Signed-off-by: Florian Westphal <fw@strlen.de>
This commit is contained in:
Florian Westphal 2023-01-05 20:22:02 +01:00
parent 2a2fa2efc6
commit 9db5d918e2
3 changed files with 0 additions and 944 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
net/ipv4/netfilter/Kconfig
View File

@ -259,20 +259,6 @@ config IP_NF_MANGLE
To compile it as a module, choose M here. If unsure, say N.
config IP_NF_TARGET_CLUSTERIP
tristate "CLUSTERIP target support"
depends on IP_NF_MANGLE
depends on NF_CONNTRACK
depends on NETFILTER_ADVANCED
select NF_CONNTRACK_MARK
select NETFILTER_FAMILY_ARP
help
The CLUSTERIP target allows you to build load-balancing clusters of
network servers without having a dedicated load-balancing
router/server/switch.
To compile it as a module, choose M here. If unsure, say N.
config IP_NF_TARGET_ECN
tristate "ECN target support"
depends on IP_NF_MANGLE

1
net/ipv4/netfilter/Makefile
View File

@ -39,7 +39,6 @@ obj-$(CONFIG_IP_NF_MATCH_AH) += ipt_ah.o
obj-$(CONFIG_IP_NF_MATCH_RPFILTER) += ipt_rpfilter.o
# targets
obj-$(CONFIG_IP_NF_TARGET_CLUSTERIP) += ipt_CLUSTERIP.o
obj-$(CONFIG_IP_NF_TARGET_ECN) += ipt_ECN.o
obj-$(CONFIG_IP_NF_TARGET_REJECT) += ipt_REJECT.o
obj-$(CONFIG_IP_NF_TARGET_SYNPROXY) += ipt_SYNPROXY.o

929
net/ipv4/netfilter/ipt_CLUSTERIP.c
View File

@ -1,929 +0,0 @@
// SPDX-License-Identifier: GPL-2.0-only
/* Cluster IP hashmark target
* (C) 2003-2004 by Harald Welte <laforge@netfilter.org>
* based on ideas of Fabio Olive Leite <olive@unixforge.org>
*
* Development of this code funded by SuSE Linux AG, https://www.suse.com/
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/proc_fs.h>
#include <linux/jhash.h>
#include <linux/bitops.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/ip.h>
#include <linux/tcp.h>
#include <linux/udp.h>
#include <linux/icmp.h>
#include <linux/if_arp.h>
#include <linux/seq_file.h>
#include <linux/refcount.h>
#include <linux/netfilter_arp.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/netfilter_ipv4/ipt_CLUSTERIP.h>
#include <net/netfilter/nf_conntrack.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>
#include <net/checksum.h>
#include <net/ip.h>
#define CLUSTERIP_VERSION "0.8"
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
MODULE_DESCRIPTION("Xtables: CLUSTERIP target");
struct clusterip_config {
struct list_head list; /* list of all configs */
refcount_t refcount; /* reference count */
refcount_t entries; /* number of entries/rules
* referencing us */
__be32 clusterip; /* the IP address */
u_int8_t clustermac[ETH_ALEN]; /* the MAC address */
int ifindex; /* device ifindex */
u_int16_t num_total_nodes; /* total number of nodes */
unsigned long local_nodes; /* node number array */
#ifdef CONFIG_PROC_FS
struct proc_dir_entry *pde; /* proc dir entry */
#endif
enum clusterip_hashmode hash_mode; /* which hashing mode */
u_int32_t hash_initval; /* hash initialization */
struct rcu_head rcu; /* for call_rcu */
struct net *net; /* netns for pernet list */
char ifname[IFNAMSIZ]; /* device ifname */
};
#ifdef CONFIG_PROC_FS
static const struct proc_ops clusterip_proc_ops;
#endif
struct clusterip_net {
struct list_head configs;
/* lock protects the configs list */
spinlock_t lock;
bool clusterip_deprecated_warning;
#ifdef CONFIG_PROC_FS
struct proc_dir_entry *procdir;
/* mutex protects the config->pde*/
struct mutex mutex;
#endif
unsigned int hook_users;
};
static unsigned int clusterip_arp_mangle(void *priv, struct sk_buff *skb, const struct nf_hook_state *state);
static const struct nf_hook_ops cip_arp_ops = {
.hook = clusterip_arp_mangle,
.pf = NFPROTO_ARP,
.hooknum = NF_ARP_OUT,
.priority = -1
};
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);
}
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);
dev = dev_get_by_name(config->net, config->ifname);
if (dev) {
dev_mc_del(dev, config->clustermac);
dev_put(dev);
}
kfree(config);
}
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);
}
/* 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 */
static inline void
clusterip_config_entry_put(struct clusterip_config *c)
{
struct clusterip_net *cn = clusterip_pernet(c->net);
local_bh_disable();
if (refcount_dec_and_lock(&c->entries, &cn->lock)) {
list_del_rcu(&c->list);
spin_unlock(&cn->lock);
local_bh_enable();
/* 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;
}
local_bh_enable();
}
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;
}
return NULL;
}
static inline struct clusterip_config *
clusterip_config_find_get(struct net *net, __be32 clusterip, int entry)
{
struct clusterip_config *c;
rcu_read_lock_bh();
c = __clusterip_config_find(net, clusterip);
if (c) {
#ifdef CONFIG_PROC_FS
if (!c->pde)
c = NULL;
else
#endif
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;
}
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);
}
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);
struct clusterip_net *cn = clusterip_pernet(net);
struct clusterip_config *c;
spin_lock_bh(&cn->lock);
list_for_each_entry_rcu(c, &cn->configs, list) {
switch (event) {
case NETDEV_REGISTER:
if (!strcmp(dev->name, c->ifname)) {
c->ifindex = dev->ifindex;
dev_mc_add(dev, c->clustermac);
}
break;
case NETDEV_UNREGISTER:
if (dev->ifindex == c->ifindex) {
dev_mc_del(dev, c->clustermac);
c->ifindex = -1;
}
break;
case NETDEV_CHANGENAME:
if (!strcmp(dev->name, c->ifname)) {
c->ifindex = dev->ifindex;
dev_mc_add(dev, c->clustermac);
} else if (dev->ifindex == c->ifindex) {
dev_mc_del(dev, c->clustermac);
c->ifindex = -1;
}
break;
}
}
spin_unlock_bh(&cn->lock);
return NOTIFY_DONE;
}
static struct clusterip_config *
clusterip_config_init(struct net *net, const struct ipt_clusterip_tgt_info *i,
__be32 ip, const char *iniface)
{
struct clusterip_net *cn = clusterip_pernet(net);
struct clusterip_config *c;
struct net_device *dev;
int err;
if (iniface[0] == '\0') {
pr_info("Please specify an interface name\n");
return ERR_PTR(-EINVAL);
}
c = kzalloc(sizeof(*c), GFP_ATOMIC);
if (!c)
return ERR_PTR(-ENOMEM);
dev = dev_get_by_name(net, iniface);
if (!dev) {
pr_info("no such interface %s\n", iniface);
kfree(c);
return ERR_PTR(-ENOENT);
}
c->ifindex = dev->ifindex;
strcpy(c->ifname, dev->name);
memcpy(&c->clustermac, &i->clustermac, ETH_ALEN);
dev_mc_add(dev, c->clustermac);
dev_put(dev);
c->clusterip = ip;
c->num_total_nodes = i->num_total_nodes;
clusterip_config_init_nodelist(c, i);
c->hash_mode = i->hash_mode;
c->hash_initval = i->hash_initval;
c->net = net;
refcount_set(&c->refcount, 1);
spin_lock_bh(&cn->lock);
if (__clusterip_config_find(net, ip)) {
err = -EBUSY;
goto out_config_put;
}
list_add_rcu(&c->list, &cn->configs);
spin_unlock_bh(&cn->lock);
#ifdef CONFIG_PROC_FS
{
char buffer[16];
/* create proc dir entry */
sprintf(buffer, "%pI4", &ip);
mutex_lock(&cn->mutex);
c->pde = proc_create_data(buffer, 0600,
cn->procdir,
&clusterip_proc_ops, c);
mutex_unlock(&cn->mutex);
if (!c->pde) {
err = -ENOMEM;
goto err;
}
}
#endif
refcount_set(&c->entries, 1);
return c;
#ifdef CONFIG_PROC_FS
err:
#endif
spin_lock_bh(&cn->lock);
list_del_rcu(&c->list);
out_config_put:
spin_unlock_bh(&cn->lock);
clusterip_config_put(c);
return ERR_PTR(err);
}
#ifdef CONFIG_PROC_FS
static int
clusterip_add_node(struct clusterip_config *c, u_int16_t nodenum)
{
if (nodenum == 0 ||
nodenum > c->num_total_nodes)
return 1;
/* check if we already have this number in our bitfield */
if (test_and_set_bit(nodenum - 1, &c->local_nodes))
return 1;
return 0;
}
static bool
clusterip_del_node(struct clusterip_config *c, u_int16_t nodenum)
{
if (nodenum == 0 ||
nodenum > c->num_total_nodes)
return true;
if (test_and_clear_bit(nodenum - 1, &c->local_nodes))
return false;
return true;
}
#endif
static inline u_int32_t
clusterip_hashfn(const struct sk_buff *skb,
const struct clusterip_config *config)
{
const struct iphdr *iph = ip_hdr(skb);
unsigned long hashval;
u_int16_t sport = 0, dport = 0;
int poff;
poff = proto_ports_offset(iph->protocol);
if (poff >= 0) {
const u_int16_t *ports;
u16 _ports[2];
ports = skb_header_pointer(skb, iph->ihl * 4 + poff, 4, _ports);
if (ports) {
sport = ports[0];
dport = ports[1];
}
} else {
net_info_ratelimited("unknown protocol %u\n", iph->protocol);
}
switch (config->hash_mode) {
case CLUSTERIP_HASHMODE_SIP:
hashval = jhash_1word(ntohl(iph->saddr),
config->hash_initval);
break;
case CLUSTERIP_HASHMODE_SIP_SPT:
hashval = jhash_2words(ntohl(iph->saddr), sport,
config->hash_initval);
break;
case CLUSTERIP_HASHMODE_SIP_SPT_DPT:
hashval = jhash_3words(ntohl(iph->saddr), sport, dport,
config->hash_initval);
break;
default:
/* to make gcc happy */
hashval = 0;
/* This cannot happen, unless the check function wasn't called
* at rule load time */
pr_info("unknown mode %u\n", config->hash_mode);
BUG();
break;
}
/* node numbers are 1..n, not 0..n */
return reciprocal_scale(hashval, config->num_total_nodes) + 1;
}
static inline int
clusterip_responsible(const struct clusterip_config *config, u_int32_t hash)
{
return test_bit(hash - 1, &config->local_nodes);
}
/***********************************************************************
* IPTABLES TARGET
***********************************************************************/
static unsigned int
clusterip_tg(struct sk_buff *skb, const struct xt_action_param *par)
{
const struct ipt_clusterip_tgt_info *cipinfo = par->targinfo;
struct nf_conn *ct;
enum ip_conntrack_info ctinfo;
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() */
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 ||
ctinfo == IP_CT_RELATED_REPLY))
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;
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;
struct clusterip_net *cn = clusterip_pernet(par->net);
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 (cn->hook_users == UINT_MAX)
return -EOVERFLOW;
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 (cn->hook_users == 0) {
ret = nf_register_net_hook(par->net, &cip_arp_ops);
if (ret < 0) {
clusterip_config_entry_put(config);
clusterip_config_put(config);
nf_ct_netns_put(par->net, par->family);
return ret;
}
}
cn->hook_users++;
if (!cn->clusterip_deprecated_warning) {
pr_info("ipt_CLUSTERIP is deprecated and it will removed soon, "
"use xt_cluster instead\n");
cn->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;
struct clusterip_net *cn = clusterip_pernet(par->net);
/* 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);
cn->hook_users--;
if (cn->hook_users == 0)
nf_unregister_net_hook(par->net, &cip_arp_ops);
}
#ifdef CONFIG_NETFILTER_XTABLES_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_NETFILTER_XTABLES_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_NETFILTER_XTABLES_COMPAT
.compatsize = sizeof(struct compat_ipt_clusterip_tgt_info),
#endif /* CONFIG_NETFILTER_XTABLES_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
clusterip_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;
}
/***********************************************************************
* 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);
INIT_LIST_HEAD(&cn->configs);
spin_lock_init(&cn->lock);
#ifdef CONFIG_PROC_FS
cn->procdir = proc_mkdir("ipt_CLUSTERIP", net->proc_net);
if (!cn->procdir) {
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
}
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);