- 根目录:
- net
- netfilter
- nf_tables_api.c
/*
* Copyright (c) 2007-2009 Patrick McHardy <kaber@trash.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Development of this code funded by Astaro AG (http://www.astaro.com/)
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/skbuff.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nfnetlink.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables_core.h>
#include <net/netfilter/nf_tables.h>
#include <net/net_namespace.h>
#include <net/sock.h>
static LIST_HEAD(nf_tables_expressions);
/**
* nft_register_afinfo - register nf_tables address family info
*
* @afi: address family info to register
*
* Register the address family for use with nf_tables. Returns zero on
* success or a negative errno code otherwise.
*/
int nft_register_afinfo(struct net *net, struct nft_af_info *afi)
{
INIT_LIST_HEAD(&afi->tables);
nfnl_lock(NFNL_SUBSYS_NFTABLES);
list_add_tail(&afi->list, &net->nft.af_info);
nfnl_unlock(NFNL_SUBSYS_NFTABLES);
return 0;
}
EXPORT_SYMBOL_GPL(nft_register_afinfo);
/**
* nft_unregister_afinfo - unregister nf_tables address family info
*
* @afi: address family info to unregister
*
* Unregister the address family for use with nf_tables.
*/
void nft_unregister_afinfo(struct nft_af_info *afi)
{
nfnl_lock(NFNL_SUBSYS_NFTABLES);
list_del(&afi->list);
nfnl_unlock(NFNL_SUBSYS_NFTABLES);
}
EXPORT_SYMBOL_GPL(nft_unregister_afinfo);
static struct nft_af_info *nft_afinfo_lookup(struct net *net, int family)
{
struct nft_af_info *afi;
list_for_each_entry(afi, &net->nft.af_info, list) {
if (afi->family == family)
return afi;
}
return NULL;
}
static struct nft_af_info *
nf_tables_afinfo_lookup(struct net *net, int family, bool autoload)
{
struct nft_af_info *afi;
afi = nft_afinfo_lookup(net, family);
if (afi != NULL)
return afi;
#ifdef CONFIG_MODULES
if (autoload) {
nfnl_unlock(NFNL_SUBSYS_NFTABLES);
request_module("nft-afinfo-%u", family);
nfnl_lock(NFNL_SUBSYS_NFTABLES);
afi = nft_afinfo_lookup(net, family);
if (afi != NULL)
return ERR_PTR(-EAGAIN);
}
#endif
return ERR_PTR(-EAFNOSUPPORT);
}
/*
* Tables
*/
static struct nft_table *nft_table_lookup(const struct nft_af_info *afi,
const struct nlattr *nla)
{
struct nft_table *table;
list_for_each_entry(table, &afi->tables, list) {
if (!nla_strcmp(nla, table->name))
return table;
}
return NULL;
}
static struct nft_table *nf_tables_table_lookup(const struct nft_af_info *afi,
const struct nlattr *nla)
{
struct nft_table *table;
if (nla == NULL)
return ERR_PTR(-EINVAL);
table = nft_table_lookup(afi, nla);
if (table != NULL)
return table;
return ERR_PTR(-ENOENT);
}
static inline u64 nf_tables_alloc_handle(struct nft_table *table)
{
return ++table->hgenerator;
}
static const struct nf_chain_type *chain_type[AF_MAX][NFT_CHAIN_T_MAX];
static const struct nf_chain_type *
__nf_tables_chain_type_lookup(int family, const struct nlattr *nla)
{
int i;
for (i = 0; i < NFT_CHAIN_T_MAX; i++) {
if (chain_type[family][i] != NULL &&
!nla_strcmp(nla, chain_type[family][i]->name))
return chain_type[family][i];
}
return NULL;
}
static const struct nf_chain_type *
nf_tables_chain_type_lookup(const struct nft_af_info *afi,
const struct nlattr *nla,
bool autoload)
{
const struct nf_chain_type *type;
type = __nf_tables_chain_type_lookup(afi->family, nla);
if (type != NULL)
return type;
#ifdef CONFIG_MODULES
if (autoload) {
nfnl_unlock(NFNL_SUBSYS_NFTABLES);
request_module("nft-chain-%u-%*.s", afi->family,
nla_len(nla)-1, (const char *)nla_data(nla));
nfnl_lock(NFNL_SUBSYS_NFTABLES);
type = __nf_tables_chain_type_lookup(afi->family, nla);
if (type != NULL)
return ERR_PTR(-EAGAIN);
}
#endif
return ERR_PTR(-ENOENT);
}
static const struct nla_policy nft_table_policy[NFTA_TABLE_MAX + 1] = {
[NFTA_TABLE_NAME] = { .type = NLA_STRING },
[NFTA_TABLE_FLAGS] = { .type = NLA_U32 },
};
static int nf_tables_fill_table_info(struct sk_buff *skb, u32 portid, u32 seq,
int event, u32 flags, int family,
const struct nft_table *table)
{
struct nlmsghdr *nlh;
struct nfgenmsg *nfmsg;
event |= NFNL_SUBSYS_NFTABLES << 8;
nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct nfgenmsg), flags);
if (nlh == NULL)
goto nla_put_failure;
nfmsg = nlmsg_data(nlh);
nfmsg->nfgen_family = family;
nfmsg->version = NFNETLINK_V0;
nfmsg->res_id = 0;
if (nla_put_string(skb, NFTA_TABLE_NAME, table->name) ||
nla_put_be32(skb, NFTA_TABLE_FLAGS, htonl(table->flags)) ||
nla_put_be32(skb, NFTA_TABLE_USE, htonl(table->use)))
goto nla_put_failure;
return nlmsg_end(skb, nlh);
nla_put_failure:
nlmsg_trim(skb, nlh);
return -1;
}
static int nf_tables_table_notify(const struct sk_buff *oskb,
const struct nlmsghdr *nlh,
const struct nft_table *table,
int event, int family)
{
struct sk_buff *skb;
u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
u32 seq = nlh ? nlh->nlmsg_seq : 0;
struct net *net = oskb ? sock_net(oskb->sk) : &init_net;
bool report;
int err;
report = nlh ? nlmsg_report(nlh) : false;
if (!report && !nfnetlink_has_listeners(net, NFNLGRP_NFTABLES))
return 0;
err = -ENOBUFS;
skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
if (skb == NULL)
goto err;
err = nf_tables_fill_table_info(skb, portid, seq, event, 0,
family, table);
if (err < 0) {
kfree_skb(skb);
goto err;
}
err = nfnetlink_send(skb, net, portid, NFNLGRP_NFTABLES, report,
GFP_KERNEL);
err:
if (err < 0)
nfnetlink_set_err(net, portid, NFNLGRP_NFTABLES, err);
return err;
}
static int nf_tables_dump_tables(struct sk_buff *skb,
struct netlink_callback *cb)
{
const struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
const struct nft_af_info *afi;
const struct nft_table *table;
unsigned int idx = 0, s_idx = cb->args[0];
struct net *net = sock_net(skb->sk);
int family = nfmsg->nfgen_family;
list_for_each_entry(afi, &net->nft.af_info, list) {
if (family != NFPROTO_UNSPEC && family != afi->family)
continue;
list_for_each_entry(table, &afi->tables, list) {
if (idx < s_idx)
goto cont;
if (idx > s_idx)
memset(&cb->args[1], 0,
sizeof(cb->args) - sizeof(cb->args[0]));
if (nf_tables_fill_table_info(skb,
NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq,
NFT_MSG_NEWTABLE,
NLM_F_MULTI,
afi->family, table) < 0)
goto done;
cont:
idx++;
}
}
done:
cb->args[0] = idx;
return skb->len;
}
static int nf_tables_gettable(struct sock *nlsk, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const nla[])
{
const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
const struct nft_af_info *afi;
const struct nft_table *table;
struct sk_buff *skb2;
struct net *net = sock_net(skb->sk);
int family = nfmsg->nfgen_family;
int err;
if (nlh->nlmsg_flags & NLM_F_DUMP) {
struct netlink_dump_control c = {
.dump = nf_tables_dump_tables,
};
return netlink_dump_start(nlsk, skb, nlh, &c);
}
afi = nf_tables_afinfo_lookup(net, family, false);
if (IS_ERR(afi))
return PTR_ERR(afi);
table = nf_tables_table_lookup(afi, nla[NFTA_TABLE_NAME]);
if (IS_ERR(table))
return PTR_ERR(table);
skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
if (!skb2)
return -ENOMEM;
err = nf_tables_fill_table_info(skb2, NETLINK_CB(skb).portid,
nlh->nlmsg_seq, NFT_MSG_NEWTABLE, 0,
family, table);
if (err < 0)
goto err;
return nlmsg_unicast(nlsk, skb2, NETLINK_CB(skb).portid);
err:
kfree_skb(skb2);
return err;
}
static int nf_tables_table_enable(const struct nft_af_info *afi,
struct nft_table *table)
{
struct nft_chain *chain;
int err, i = 0;
list_for_each_entry(chain, &table->chains, list) {
if (!(chain->flags & NFT_BASE_CHAIN))
continue;
err = nf_register_hooks(nft_base_chain(chain)->ops, afi->nops);
if (err < 0)
goto err;
i++;
}
return 0;
err:
list_for_each_entry(chain, &table->chains, list) {
if (!(chain->flags & NFT_BASE_CHAIN))
continue;
if (i-- <= 0)
break;
nf_unregister_hooks(nft_base_chain(chain)->ops, afi->nops);
}
return err;
}
static int nf_tables_table_disable(const struct nft_af_info *afi,
struct nft_table *table)
{
struct nft_chain *chain;
list_for_each_entry(chain, &table->chains, list) {
if (chain->flags & NFT_BASE_CHAIN)
nf_unregister_hooks(nft_base_chain(chain)->ops,
afi->nops);
}
return 0;
}
static int nf_tables_updtable(struct sock *nlsk, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const nla[],
struct nft_af_info *afi, struct nft_table *table)
{
const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
int family = nfmsg->nfgen_family, ret = 0;
if (nla[NFTA_TABLE_FLAGS]) {
u32 flags;
flags = ntohl(nla_get_be32(nla[NFTA_TABLE_FLAGS]));
if (flags & ~NFT_TABLE_F_DORMANT)
return -EINVAL;
if ((flags & NFT_TABLE_F_DORMANT) &&
!(table->flags & NFT_TABLE_F_DORMANT)) {
ret = nf_tables_table_disable(afi, table);
if (ret >= 0)
table->flags |= NFT_TABLE_F_DORMANT;
} else if (!(flags & NFT_TABLE_F_DORMANT) &&
table->flags & NFT_TABLE_F_DORMANT) {
ret = nf_tables_table_enable(afi, table);
if (ret >= 0)
table->flags &= ~NFT_TABLE_F_DORMANT;
}
if (ret < 0)
goto err;
}
nf_tables_table_notify(skb, nlh, table, NFT_MSG_NEWTABLE, family);
err:
return ret;
}
static int nf_tables_newtable(struct sock *nlsk, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const nla[])
{
const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
const struct nlattr *name;
struct nft_af_info *afi;
struct nft_table *table;
struct net *net = sock_net(skb->sk);
int family = nfmsg->nfgen_family;
u32 flags = 0;
afi = nf_tables_afinfo_lookup(net, family, true);
if (IS_ERR(afi))
return PTR_ERR(afi);
name = nla[NFTA_TABLE_NAME];
table = nf_tables_table_lookup(afi, name);
if (IS_ERR(table)) {
if (PTR_ERR(table) != -ENOENT)
return PTR_ERR(table);
table = NULL;
}
if (table != NULL) {
if (nlh->nlmsg_flags & NLM_F_EXCL)
return -EEXIST;
if (nlh->nlmsg_flags & NLM_F_REPLACE)
return -EOPNOTSUPP;
return nf_tables_updtable(nlsk, skb, nlh, nla, afi, table);
}
if (nla[NFTA_TABLE_FLAGS]) {
flags = ntohl(nla_get_be32(nla[NFTA_TABLE_FLAGS]));
if (flags & ~NFT_TABLE_F_DORMANT)
return -EINVAL;
}
if (!try_module_get(afi->owner))
return -EAFNOSUPPORT;
table = kzalloc(sizeof(*table) + nla_len(name), GFP_KERNEL);
if (table == NULL) {
module_put(afi->owner);
return -ENOMEM;
}
nla_strlcpy(table->name, name, nla_len(name));
INIT_LIST_HEAD(&table->chains);
INIT_LIST_HEAD(&table->sets);
table->flags = flags;
list_add_tail(&table->list, &afi->tables);
nf_tables_table_notify(skb, nlh, table, NFT_MSG_NEWTABLE, family);
return 0;
}
static int nf_tables_deltable(struct sock *nlsk, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const nla[])
{
const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
struct nft_af_info *afi;
struct nft_table *table;
struct net *net = sock_net(skb->sk);
int family = nfmsg->nfgen_family;
afi = nf_tables_afinfo_lookup(net, family, false);
if (IS_ERR(afi))
return PTR_ERR(afi);
table = nf_tables_table_lookup(afi, nla[NFTA_TABLE_NAME]);
if (IS_ERR(table))
return PTR_ERR(table);
if (!list_empty(&table->chains) || !list_empty(&table->sets))
return -EBUSY;
list_del(&table->list);
nf_tables_table_notify(skb, nlh, table, NFT_MSG_DELTABLE, family);
kfree(table);
module_put(afi->owner);
return 0;
}
int nft_register_chain_type(const struct nf_chain_type *ctype)
{
int err = 0;
nfnl_lock(NFNL_SUBSYS_NFTABLES);
if (chain_type[ctype->family][ctype->type] != NULL) {
err = -EBUSY;
goto out;
}
chain_type[ctype->family][ctype->type] = ctype;
out:
nfnl_unlock(NFNL_SUBSYS_NFTABLES);
return err;
}
EXPORT_SYMBOL_GPL(nft_register_chain_type);
void nft_unregister_chain_type(const struct nf_chain_type *ctype)
{
nfnl_lock(NFNL_SUBSYS_NFTABLES);
chain_type[ctype->family][ctype->type] = NULL;
nfnl_unlock(NFNL_SUBSYS_NFTABLES);
}
EXPORT_SYMBOL_GPL(nft_unregister_chain_type);
/*
* Chains
*/
static struct nft_chain *
nf_tables_chain_lookup_byhandle(const struct nft_table *table, u64 handle)
{
struct nft_chain *chain;
list_for_each_entry(chain, &table->chains, list) {
if (chain->handle == handle)
return chain;
}
return ERR_PTR(-ENOENT);
}
static struct nft_chain *nf_tables_chain_lookup(const struct nft_table *table,
const struct nlattr *nla)
{
struct nft_chain *chain;
if (nla == NULL)
return ERR_PTR(-EINVAL);
list_for_each_entry(chain, &table->chains, list) {
if (!nla_strcmp(nla, chain->name))
return chain;
}
return ERR_PTR(-ENOENT);
}
static const struct nla_policy nft_chain_policy[NFTA_CHAIN_MAX + 1] = {
[NFTA_CHAIN_TABLE] = { .type = NLA_STRING },
[NFTA_CHAIN_HANDLE] = { .type = NLA_U64 },
[NFTA_CHAIN_NAME] = { .type = NLA_STRING,
.len = NFT_CHAIN_MAXNAMELEN - 1 },
[NFTA_CHAIN_HOOK] = { .type = NLA_NESTED },
[NFTA_CHAIN_POLICY] = { .type = NLA_U32 },
[NFTA_CHAIN_TYPE] = { .type = NLA_NUL_STRING },
[NFTA_CHAIN_COUNTERS] = { .type = NLA_NESTED },
};
static const struct nla_policy nft_hook_policy[NFTA_HOOK_MAX + 1] = {
[NFTA_HOOK_HOOKNUM] = { .type = NLA_U32 },
[NFTA_HOOK_PRIORITY] = { .type = NLA_U32 },
};
static int nft_dump_stats(struct sk_buff *skb, struct nft_stats __percpu *stats)
{
struct nft_stats *cpu_stats, total;
struct nlattr *nest;
int cpu;
memset(&total, 0, sizeof(total));
for_each_possible_cpu(cpu) {
cpu_stats = per_cpu_ptr(stats, cpu);
total.pkts += cpu_stats->pkts;
total.bytes += cpu_stats->bytes;
}
nest = nla_nest_start(skb, NFTA_CHAIN_COUNTERS);
if (nest == NULL)
goto nla_put_failure;
if (nla_put_be64(skb, NFTA_COUNTER_PACKETS, cpu_to_be64(total.pkts)) ||
nla_put_be64(skb, NFTA_COUNTER_BYTES, cpu_to_be64(total.bytes)))
goto nla_put_failure;
nla_nest_end(skb, nest);
return 0;
nla_put_failure:
return -ENOSPC;
}
static int nf_tables_fill_chain_info(struct sk_buff *skb, u32 portid, u32 seq,
int event, u32 flags, int family,
const struct nft_table *table,
const struct nft_chain *chain)
{
struct nlmsghdr *nlh;
struct nfgenmsg *nfmsg;
event |= NFNL_SUBSYS_NFTABLES << 8;
nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct nfgenmsg), flags);
if (nlh == NULL)
goto nla_put_failure;
nfmsg = nlmsg_data(nlh);
nfmsg->nfgen_family = family;
nfmsg->version = NFNETLINK_V0;
nfmsg->res_id = 0;
if (nla_put_string(skb, NFTA_CHAIN_TABLE, table->name))
goto nla_put_failure;
if (nla_put_be64(skb, NFTA_CHAIN_HANDLE, cpu_to_be64(chain->handle)))
goto nla_put_failure;
if (nla_put_string(skb, NFTA_CHAIN_NAME, chain->name))
goto nla_put_failure;
if (chain->flags & NFT_BASE_CHAIN) {
const struct nft_base_chain *basechain = nft_base_chain(chain);
const struct nf_hook_ops *ops = &basechain->ops[0];
struct nlattr *nest;
nest = nla_nest_start(skb, NFTA_CHAIN_HOOK);
if (nest == NULL)
goto nla_put_failure;
if (nla_put_be32(skb, NFTA_HOOK_HOOKNUM, htonl(ops->hooknum)))
goto nla_put_failure;
if (nla_put_be32(skb, NFTA_HOOK_PRIORITY, htonl(ops->priority)))
goto nla_put_failure;
nla_nest_end(skb, nest);
if (nla_put_be32(skb, NFTA_CHAIN_POLICY,
htonl(basechain->policy)))
goto nla_put_failure;
if (nla_put_string(skb, NFTA_CHAIN_TYPE, basechain->type->name))
goto nla_put_failure;
if (nft_dump_stats(skb, nft_base_chain(chain)->stats))
goto nla_put_failure;
}
if (nla_put_be32(skb, NFTA_CHAIN_USE, htonl(chain->use)))
goto nla_put_failure;
return nlmsg_end(skb, nlh);
nla_put_failure:
nlmsg_trim(skb, nlh);
return -1;
}
static int nf_tables_chain_notify(const struct sk_buff *oskb,
const struct nlmsghdr *nlh,
const struct nft_table *table,
const struct nft_chain *chain,
int event, int family)
{
struct sk_buff *skb;
u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
struct net *net = oskb ? sock_net(oskb->sk) : &init_net;
u32 seq = nlh ? nlh->nlmsg_seq : 0;
bool report;
int err;
report = nlh ? nlmsg_report(nlh) : false;
if (!report && !nfnetlink_has_listeners(net, NFNLGRP_NFTABLES))
return 0;
err = -ENOBUFS;
skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
if (skb == NULL)
goto err;
err = nf_tables_fill_chain_info(skb, portid, seq, event, 0, family,
table, chain);
if (err < 0) {
kfree_skb(skb);
goto err;
}
err = nfnetlink_send(skb, net, portid, NFNLGRP_NFTABLES, report,
GFP_KERNEL);
err:
if (err < 0)
nfnetlink_set_err(net, portid, NFNLGRP_NFTABLES, err);
return err;
}
static int nf_tables_dump_chains(struct sk_buff *skb,
struct netlink_callback *cb)
{
const struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
const struct nft_af_info *afi;
const struct nft_table *table;
const struct nft_chain *chain;
unsigned int idx = 0, s_idx = cb->args[0];
struct net *net = sock_net(skb->sk);
int family = nfmsg->nfgen_family;
list_for_each_entry(afi, &net->nft.af_info, list) {
if (family != NFPROTO_UNSPEC && family != afi->family)
continue;
list_for_each_entry(table, &afi->tables, list) {
list_for_each_entry(chain, &table->chains, list) {
if (idx < s_idx)
goto cont;
if (idx > s_idx)
memset(&cb->args[1], 0,
sizeof(cb->args) - sizeof(cb->args[0]));
if (nf_tables_fill_chain_info(skb, NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq,
NFT_MSG_NEWCHAIN,
NLM_F_MULTI,
afi->family, table, chain) < 0)
goto done;
cont:
idx++;
}
}
}
done:
cb->args[0] = idx;
return skb->len;
}
static int nf_tables_getchain(struct sock *nlsk, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const nla[])
{
const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
const struct nft_af_info *afi;
const struct nft_table *table;
const struct nft_chain *chain;
struct sk_buff *skb2;
struct net *net = sock_net(skb->sk);
int family = nfmsg->nfgen_family;
int err;
if (nlh->nlmsg_flags & NLM_F_DUMP) {
struct netlink_dump_control c = {
.dump = nf_tables_dump_chains,
};
return netlink_dump_start(nlsk, skb, nlh, &c);
}
afi = nf_tables_afinfo_lookup(net, family, false);
if (IS_ERR(afi))
return PTR_ERR(afi);
table = nf_tables_table_lookup(afi, nla[NFTA_CHAIN_TABLE]);
if (IS_ERR(table))
return PTR_ERR(table);
chain = nf_tables_chain_lookup(table, nla[NFTA_CHAIN_NAME]);
if (IS_ERR(chain))
return PTR_ERR(chain);
skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
if (!skb2)
return -ENOMEM;
err = nf_tables_fill_chain_info(skb2, NETLINK_CB(skb).portid,
nlh->nlmsg_seq, NFT_MSG_NEWCHAIN, 0,
family, table, chain);
if (err < 0)
goto err;
return nlmsg_unicast(nlsk, skb2, NETLINK_CB(skb).portid);
err:
kfree_skb(skb2);
return err;
}
static const struct nla_policy nft_counter_policy[NFTA_COUNTER_MAX + 1] = {
[NFTA_COUNTER_PACKETS] = { .type = NLA_U64 },
[NFTA_COUNTER_BYTES] = { .type = NLA_U64 },
};
static int
nf_tables_counters(struct nft_base_chain *chain, const struct nlattr *attr)
{
struct nlattr *tb[NFTA_COUNTER_MAX+1];
struct nft_stats __percpu *newstats;
struct nft_stats *stats;
int err;
err = nla_parse_nested(tb, NFTA_COUNTER_MAX, attr, nft_counter_policy);
if (err < 0)
return err;
if (!tb[NFTA_COUNTER_BYTES] || !tb[NFTA_COUNTER_PACKETS])
return -EINVAL;
newstats = alloc_percpu(struct nft_stats);
if (newstats == NULL)
return -ENOMEM;
/* Restore old counters on this cpu, no problem. Per-cpu statistics
* are not exposed to userspace.
*/
stats = this_cpu_ptr(newstats);
stats->bytes = be64_to_cpu(nla_get_be64(tb[NFTA_COUNTER_BYTES]));
stats->pkts = be64_to_cpu(nla_get_be64(tb[NFTA_COUNTER_PACKETS]));
if (chain->stats) {
/* nfnl_lock is held, add some nfnl function for this, later */
struct nft_stats __percpu *oldstats =
rcu_dereference_protected(chain->stats, 1);
rcu_assign_pointer(chain->stats, newstats);
synchronize_rcu();
free_percpu(oldstats);
} else
rcu_assign_pointer(chain->stats, newstats);
return 0;
}
static int nf_tables_newchain(struct sock *nlsk, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const nla[])
{
const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
const struct nlattr * uninitialized_var(name);
const struct nft_af_info *afi;
struct nft_table *table;
struct nft_chain *chain;
struct nft_base_chain *basechain = NULL;
struct nlattr *ha[NFTA_HOOK_MAX + 1];
struct net *net = sock_net(skb->sk);
int family = nfmsg->nfgen_family;
u8 policy = NF_ACCEPT;
u64 handle = 0;
unsigned int i;
int err;
bool create;
create = nlh->nlmsg_flags & NLM_F_CREATE ? true : false;
afi = nf_tables_afinfo_lookup(net, family, true);
if (IS_ERR(afi))
return PTR_ERR(afi);
table = nf_tables_table_lookup(afi, nla[NFTA_CHAIN_TABLE]);
if (IS_ERR(table))
return PTR_ERR(table);
chain = NULL;
name = nla[NFTA_CHAIN_NAME];
if (nla[NFTA_CHAIN_HANDLE]) {
handle = be64_to_cpu(nla_get_be64(nla[NFTA_CHAIN_HANDLE]));
chain = nf_tables_chain_lookup_byhandle(table, handle);
if (IS_ERR(chain))
return PTR_ERR(chain);
} else {
chain = nf_tables_chain_lookup(table, name);
if (IS_ERR(chain)) {
if (PTR_ERR(chain) != -ENOENT)
return PTR_ERR(chain);
chain = NULL;
}
}
if (nla[NFTA_CHAIN_POLICY]) {
if ((chain != NULL &&
!(chain->flags & NFT_BASE_CHAIN)) ||
nla[NFTA_CHAIN_HOOK] == NULL)
return -EOPNOTSUPP;
policy = ntohl(nla_get_be32(nla[NFTA_CHAIN_POLICY]));
switch (policy) {
case NF_DROP:
case NF_ACCEPT:
break;
default:
return -EINVAL;
}
}
if (chain != NULL) {
if (nlh->nlmsg_flags & NLM_F_EXCL)
return -EEXIST;
if (nlh->nlmsg_flags & NLM_F_REPLACE)
return -EOPNOTSUPP;
if (nla[NFTA_CHAIN_HANDLE] && name &&
!IS_ERR(nf_tables_chain_lookup(table, nla[NFTA_CHAIN_NAME])))
return -EEXIST;
if (nla[NFTA_CHAIN_COUNTERS]) {
if (!(chain->flags & NFT_BASE_CHAIN))
return -EOPNOTSUPP;
err = nf_tables_counters(nft_base_chain(chain),
nla[NFTA_CHAIN_COUNTERS]);
if (err < 0)
return err;
}
if (nla[NFTA_CHAIN_POLICY])
nft_base_chain(chain)->policy = policy;
if (nla[NFTA_CHAIN_HANDLE] && name)
nla_strlcpy(chain->name, name, NFT_CHAIN_MAXNAMELEN);
goto notify;
}
if (table->use == UINT_MAX)
return -EOVERFLOW;
if (nla[NFTA_CHAIN_HOOK]) {
const struct nf_chain_type *type;
struct nf_hook_ops *ops;
nf_hookfn *hookfn;
u32 hooknum, priority;
type = chain_type[family][NFT_CHAIN_T_DEFAULT];
if (nla[NFTA_CHAIN_TYPE]) {
type = nf_tables_chain_type_lookup(afi,
nla[NFTA_CHAIN_TYPE],
create);
if (IS_ERR(type))
return PTR_ERR(type);
}
err = nla_parse_nested(ha, NFTA_HOOK_MAX, nla[NFTA_CHAIN_HOOK],
nft_hook_policy);
if (err < 0)
return err;
if (ha[NFTA_HOOK_HOOKNUM] == NULL ||
ha[NFTA_HOOK_PRIORITY] == NULL)
return -EINVAL;
hooknum = ntohl(nla_get_be32(ha[NFTA_HOOK_HOOKNUM]));
if (hooknum >= afi->nhooks)
return -EINVAL;
priority = ntohl(nla_get_be32(ha[NFTA_HOOK_PRIORITY]));
if (!(type->hook_mask & (1 << hooknum)))
return -EOPNOTSUPP;
if (!try_module_get(type->owner))
return -ENOENT;
hookfn = type->hooks[hooknum];
basechain = kzalloc(sizeof(*basechain), GFP_KERNEL);
if (basechain == NULL)
return -ENOMEM;
if (nla[NFTA_CHAIN_COUNTERS]) {
err = nf_tables_counters(basechain,
nla[NFTA_CHAIN_COUNTERS]);
if (err < 0) {
module_put(type->owner);
kfree(basechain);
return err;
}
} else {
struct nft_stats __percpu *newstats;
newstats = alloc_percpu(struct nft_stats);
if (newstats == NULL) {
module_put(type->owner);
kfree(basechain);
return -ENOMEM;
}
rcu_assign_pointer(basechain->stats, newstats);
}
basechain->type = type;
chain = &basechain->chain;
for (i = 0; i < afi->nops; i++) {
ops = &basechain->ops[i];
ops->pf = family;
ops->owner = afi->owner;
ops->hooknum = hooknum;
ops->priority = priority;
ops->priv = chain;
ops->hook = afi->hooks[ops->hooknum];
if (hookfn)
ops->hook = hookfn;
if (afi->hook_ops_init)
afi->hook_ops_init(ops, i);
}
chain->flags |= NFT_BASE_CHAIN;
basechain->policy = policy;
} else {
chain = kzalloc(sizeof(*chain), GFP_KERNEL);
if (chain == NULL)
return -ENOMEM;
}
INIT_LIST_HEAD(&chain->rules);
chain->handle = nf_tables_alloc_handle(table);
chain->net = net;
chain->table = table;
nla_strlcpy(chain->name, name, NFT_CHAIN_MAXNAMELEN);
if (!(table->flags & NFT_TABLE_F_DORMANT) &&
chain->flags & NFT_BASE_CHAIN) {
err = nf_register_hooks(nft_base_chain(chain)->ops, afi->nops);
if (err < 0) {
module_put(basechain->type->owner);
free_percpu(basechain->stats);
kfree(basechain);
return err;
}
}
list_add_tail(&chain->list, &table->chains);
table->use++;
notify:
nf_tables_chain_notify(skb, nlh, table, chain, NFT_MSG_NEWCHAIN,
family);
return 0;
}
static void nf_tables_chain_destroy(struct nft_chain *chain)
{
BUG_ON(chain->use > 0);
if (chain->flags & NFT_BASE_CHAIN) {
module_put(nft_base_chain(chain)->type->owner);
free_percpu(nft_base_chain(chain)->stats);
kfree(nft_base_chain(chain));
} else
kfree(chain);
}
static int nf_tables_delchain(struct sock *nlsk, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const nla[])
{
const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
const struct nft_af_info *afi;
struct nft_table *table;
struct nft_chain *chain;
struct net *net = sock_net(skb->sk);
int family = nfmsg->nfgen_family;
afi = nf_tables_afinfo_lookup(net, family, false);
if (IS_ERR(afi))
return PTR_ERR(afi);
table = nf_tables_table_lookup(afi, nla[NFTA_CHAIN_TABLE]);
if (IS_ERR(table))
return PTR_ERR(table);
chain = nf_tables_chain_lookup(table, nla[NFTA_CHAIN_NAME]);
if (IS_ERR(chain))
return PTR_ERR(chain);
if (!list_empty(&chain->rules) || chain->use > 0)
return -EBUSY;
list_del(&chain->list);
table->use--;
if (!(table->flags & NFT_TABLE_F_DORMANT) &&
chain->flags & NFT_BASE_CHAIN)
nf_unregister_hooks(nft_base_chain(chain)->ops, afi->nops);
nf_tables_chain_notify(skb, nlh, table, chain, NFT_MSG_DELCHAIN,
family);
/* Make sure all rule references are gone before this is released */
synchronize_rcu();
nf_tables_chain_destroy(chain);
return 0;
}
static void nft_ctx_init(struct nft_ctx *ctx,
const struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nft_af_info *afi,
const struct nft_table *table,
const struct nft_chain *chain,
const struct nlattr * const *nla)
{
ctx->net = sock_net(skb->sk);
ctx->skb = skb;
ctx->nlh = nlh;
ctx->afi = afi;
ctx->table = table;
ctx->chain = chain;
ctx->nla = nla;
}
/*
* Expressions
*/
/**
* nft_register_expr - register nf_tables expr type
* @ops: expr type
*
* Registers the expr type for use with nf_tables. Returns zero on
* success or a negative errno code otherwise.
*/
int nft_register_expr(struct nft_expr_type *type)
{
nfnl_lock(NFNL_SUBSYS_NFTABLES);
list_add_tail(&type->list, &nf_tables_expressions);
nfnl_unlock(NFNL_SUBSYS_NFTABLES);
return 0;
}
EXPORT_SYMBOL_GPL(nft_register_expr);
/**
* nft_unregister_expr - unregister nf_tables expr type
* @ops: expr type
*
* Unregisters the expr typefor use with nf_tables.
*/
void nft_unregister_expr(struct nft_expr_type *type)
{
nfnl_lock(NFNL_SUBSYS_NFTABLES);
list_del(&type->list);
nfnl_unlock(NFNL_SUBSYS_NFTABLES);
}
EXPORT_SYMBOL_GPL(nft_unregister_expr);
static const struct nft_expr_type *__nft_expr_type_get(u8 family,
struct nlattr *nla)
{
const struct nft_expr_type *type;
list_for_each_entry(type, &nf_tables_expressions, list) {
if (!nla_strcmp(nla, type->name) &&
(!type->family || type->family == family))
return type;
}
return NULL;
}
static const struct nft_expr_type *nft_expr_type_get(u8 family,
struct nlattr *nla)
{
const struct nft_expr_type *type;
if (nla == NULL)
return ERR_PTR(-EINVAL);
type = __nft_expr_type_get(family, nla);
if (type != NULL && try_module_get(type->owner))
return type;
#ifdef CONFIG_MODULES
if (type == NULL) {
nfnl_unlock(NFNL_SUBSYS_NFTABLES);
request_module("nft-expr-%u-%.*s", family,
nla_len(nla), (char *)nla_data(nla));
nfnl_lock(NFNL_SUBSYS_NFTABLES);
if (__nft_expr_type_get(family, nla))
return ERR_PTR(-EAGAIN);
nfnl_unlock(NFNL_SUBSYS_NFTABLES);
request_module("nft-expr-%.*s",
nla_len(nla), (char *)nla_data(nla));
nfnl_lock(NFNL_SUBSYS_NFTABLES);
if (__nft_expr_type_get(family, nla))
return ERR_PTR(-EAGAIN);
}
#endif
return ERR_PTR(-ENOENT);
}
static const struct nla_policy nft_expr_policy[NFTA_EXPR_MAX + 1] = {
[NFTA_EXPR_NAME] = { .type = NLA_STRING },
[NFTA_EXPR_DATA] = { .type = NLA_NESTED },
};
static int nf_tables_fill_expr_info(struct sk_buff *skb,
const struct nft_expr *expr)
{
if (nla_put_string(skb, NFTA_EXPR_NAME, expr->ops->type->name))
goto nla_put_failure;
if (expr->ops->dump) {
struct nlattr *data = nla_nest_start(skb, NFTA_EXPR_DATA);
if (data == NULL)
goto nla_put_failure;
if (expr->ops->dump(skb, expr) < 0)
goto nla_put_failure;
nla_nest_end(skb, data);
}
return skb->len;
nla_put_failure:
return -1;
};
struct nft_expr_info {
const struct nft_expr_ops *ops;
struct nlattr *tb[NFT_EXPR_MAXATTR + 1];
};
static int nf_tables_expr_parse(const struct nft_ctx *ctx,
const struct nlattr *nla,
struct nft_expr_info *info)
{
const struct nft_expr_type *type;
const struct nft_expr_ops *ops;
struct nlattr *tb[NFTA_EXPR_MAX + 1];
int err;
err = nla_parse_nested(tb, NFTA_EXPR_MAX, nla, nft_expr_policy);
if (err < 0)
return err;
type = nft_expr_type_get(ctx->afi->family, tb[NFTA_EXPR_NAME]);
if (IS_ERR(type))
return PTR_ERR(type);
if (tb[NFTA_EXPR_DATA]) {
err = nla_parse_nested(info->tb, type->maxattr,
tb[NFTA_EXPR_DATA], type->policy);
if (err < 0)
goto err1;
} else
memset(info->tb, 0, sizeof(info->tb[0]) * (type->maxattr + 1));
if (type->select_ops != NULL) {
ops = type->select_ops(ctx,
(const struct nlattr * const *)info->tb);
if (IS_ERR(ops)) {
err = PTR_ERR(ops);
goto err1;
}
} else
ops = type->ops;
info->ops = ops;
return 0;
err1:
module_put(type->owner);
return err;
}
static int nf_tables_newexpr(const struct nft_ctx *ctx,
const struct nft_expr_info *info,
struct nft_expr *expr)
{
const struct nft_expr_ops *ops = info->ops;
int err;
expr->ops = ops;
if (ops->init) {
err = ops->init(ctx, expr, (const struct nlattr **)info->tb);
if (err < 0)
goto err1;
}
return 0;
err1:
expr->ops = NULL;
return err;
}
static void nf_tables_expr_destroy(struct nft_expr *expr)
{
if (expr->ops->destroy)
expr->ops->destroy(expr);
module_put(expr->ops->type->owner);
}
/*
* Rules
*/
static struct nft_rule *__nf_tables_rule_lookup(const struct nft_chain *chain,
u64 handle)
{
struct nft_rule *rule;
// FIXME: this sucks
list_for_each_entry(rule, &chain->rules, list) {
if (handle == rule->handle)
return rule;
}
return ERR_PTR(-ENOENT);
}
static struct nft_rule *nf_tables_rule_lookup(const struct nft_chain *chain,
const struct nlattr *nla)
{
if (nla == NULL)
return ERR_PTR(-EINVAL);
return __nf_tables_rule_lookup(chain, be64_to_cpu(nla_get_be64(nla)));
}
static const struct nla_policy nft_rule_policy[NFTA_RULE_MAX + 1] = {
[NFTA_RULE_TABLE] = { .type = NLA_STRING },
[NFTA_RULE_CHAIN] = { .type = NLA_STRING,
.len = NFT_CHAIN_MAXNAMELEN - 1 },
[NFTA_RULE_HANDLE] = { .type = NLA_U64 },
[NFTA_RULE_EXPRESSIONS] = { .type = NLA_NESTED },
[NFTA_RULE_COMPAT] = { .type = NLA_NESTED },
[NFTA_RULE_POSITION] = { .type = NLA_U64 },
};
static int nf_tables_fill_rule_info(struct sk_buff *skb, u32 portid, u32 seq,
int event, u32 flags, int family,
const struct nft_table *table,
const struct nft_chain *chain,
const struct nft_rule *rule)
{
struct nlmsghdr *nlh;
struct nfgenmsg *nfmsg;
const struct nft_expr *expr, *next;
struct nlattr *list;
const struct nft_rule *prule;
int type = event | NFNL_SUBSYS_NFTABLES << 8;
nlh = nlmsg_put(skb, portid, seq, type, sizeof(struct nfgenmsg),
flags);
if (nlh == NULL)
goto nla_put_failure;
nfmsg = nlmsg_data(nlh);
nfmsg->nfgen_family = family;
nfmsg->version = NFNETLINK_V0;
nfmsg->res_id = 0;
if (nla_put_string(skb, NFTA_RULE_TABLE, table->name))
goto nla_put_failure;
if (nla_put_string(skb, NFTA_RULE_CHAIN, chain->name))
goto nla_put_failure;
if (nla_put_be64(skb, NFTA_RULE_HANDLE, cpu_to_be64(rule->handle)))
goto nla_put_failure;
if ((event != NFT_MSG_DELRULE) && (rule->list.prev != &chain->rules)) {
prule = list_entry(rule->list.prev, struct nft_rule, list);
if (nla_put_be64(skb, NFTA_RULE_POSITION,
cpu_to_be64(prule->handle)))
goto nla_put_failure;
}
list = nla_nest_start(skb, NFTA_RULE_EXPRESSIONS);
if (list == NULL)
goto nla_put_failure;
nft_rule_for_each_expr(expr, next, rule) {
struct nlattr *elem = nla_nest_start(skb, NFTA_LIST_ELEM);
if (elem == NULL)
goto nla_put_failure;
if (nf_tables_fill_expr_info(skb, expr) < 0)
goto nla_put_failure;
nla_nest_end(skb, elem);
}
nla_nest_end(skb, list);
return nlmsg_end(skb, nlh);
nla_put_failure:
nlmsg_trim(skb, nlh);
return -1;
}
static int nf_tables_rule_notify(const struct sk_buff *oskb,
const struct nlmsghdr *nlh,
const struct nft_table *table,
const struct nft_chain *chain,
const struct nft_rule *rule,
int event, u32 flags, int family)
{
struct sk_buff *skb;
u32 portid = NETLINK_CB(oskb).portid;
struct net *net = oskb ? sock_net(oskb->sk) : &init_net;
u32 seq = nlh->nlmsg_seq;
bool report;
int err;
report = nlmsg_report(nlh);
if (!report && !nfnetlink_has_listeners(net, NFNLGRP_NFTABLES))
return 0;
err = -ENOBUFS;
skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
if (skb == NULL)
goto err;
err = nf_tables_fill_rule_info(skb, portid, seq, event, flags,
family, table, chain, rule);
if (err < 0) {
kfree_skb(skb);
goto err;
}
err = nfnetlink_send(skb, net, portid, NFNLGRP_NFTABLES, report,
GFP_KERNEL);
err:
if (err < 0)
nfnetlink_set_err(net, portid, NFNLGRP_NFTABLES, err);
return err;
}
static inline bool
nft_rule_is_active(struct net *net, const struct nft_rule *rule)
{
return (rule->genmask & (1 << net->nft.gencursor)) == 0;
}
static inline int gencursor_next(struct net *net)
{
return net->nft.gencursor+1 == 1 ? 1 : 0;
}
static inline int
nft_rule_is_active_next(struct net *net, const struct nft_rule *rule)
{
return (rule->genmask & (1 << gencursor_next(net))) == 0;
}
static inline void
nft_rule_activate_next(struct net *net, struct nft_rule *rule)
{
/* Now inactive, will be active in the future */
rule->genmask = (1 << net->nft.gencursor);
}
static inline void
nft_rule_disactivate_next(struct net *net, struct nft_rule *rule)
{
rule->genmask = (1 << gencursor_next(net));
}
static inline void nft_rule_clear(struct net *net, struct nft_rule *rule)
{
rule->genmask = 0;
}
static int nf_tables_dump_rules(struct sk_buff *skb,
struct netlink_callback *cb)
{
const struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
const struct nft_af_info *afi;
const struct nft_table *table;
const struct nft_chain *chain;
const struct nft_rule *rule;
unsigned int idx = 0, s_idx = cb->args[0];
struct net *net = sock_net(skb->sk);
int family = nfmsg->nfgen_family;
u8 genctr = ACCESS_ONCE(net->nft.genctr);
u8 gencursor = ACCESS_ONCE(net->nft.gencursor);
list_for_each_entry(afi, &net->nft.af_info, list) {
if (family != NFPROTO_UNSPEC && family != afi->family)
continue;
list_for_each_entry(table, &afi->tables, list) {
list_for_each_entry(chain, &table->chains, list) {
list_for_each_entry(rule, &chain->rules, list) {
if (!nft_rule_is_active(net, rule))
goto cont;
if (idx < s_idx)
goto cont;
if (idx > s_idx)
memset(&cb->args[1], 0,
sizeof(cb->args) - sizeof(cb->args[0]));
if (nf_tables_fill_rule_info(skb, NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq,
NFT_MSG_NEWRULE,
NLM_F_MULTI | NLM_F_APPEND,
afi->family, table, chain, rule) < 0)
goto done;
cont:
idx++;
}
}
}
}
done:
/* Invalidate this dump, a transition to the new generation happened */
if (gencursor != net->nft.gencursor || genctr != net->nft.genctr)
return -EBUSY;
cb->args[0] = idx;
return skb->len;
}
static int nf_tables_getrule(struct sock *nlsk, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const nla[])
{
const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
const struct nft_af_info *afi;
const struct nft_table *table;
const struct nft_chain *chain;
const struct nft_rule *rule;
struct sk_buff *skb2;
struct net *net = sock_net(skb->sk);
int family = nfmsg->nfgen_family;
int err;
if (nlh->nlmsg_flags & NLM_F_DUMP) {
struct netlink_dump_control c = {
.dump = nf_tables_dump_rules,
};
return netlink_dump_start(nlsk, skb, nlh, &c);
}
afi = nf_tables_afinfo_lookup(net, family, false);
if (IS_ERR(afi))
return PTR_ERR(afi);
table = nf_tables_table_lookup(afi, nla[NFTA_RULE_TABLE]);
if (IS_ERR(table))
return PTR_ERR(table);
chain = nf_tables_chain_lookup(table, nla[NFTA_RULE_CHAIN]);
if (IS_ERR(chain))
return PTR_ERR(chain);
rule = nf_tables_rule_lookup(chain, nla[NFTA_RULE_HANDLE]);
if (IS_ERR(rule))
return PTR_ERR(rule);
skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
if (!skb2)
return -ENOMEM;
err = nf_tables_fill_rule_info(skb2, NETLINK_CB(skb).portid,
nlh->nlmsg_seq, NFT_MSG_NEWRULE, 0,
family, table, chain, rule);
if (err < 0)
goto err;
return nlmsg_unicast(nlsk, skb2, NETLINK_CB(skb).portid);
err:
kfree_skb(skb2);
return err;
}
static void nf_tables_rule_destroy(struct nft_rule *rule)
{
struct nft_expr *expr;
/*
* Careful: some expressions might not be initialized in case this
* is called on error from nf_tables_newrule().
*/
expr = nft_expr_first(rule);
while (expr->ops && expr != nft_expr_last(rule)) {
nf_tables_expr_destroy(expr);
expr = nft_expr_next(expr);
}
kfree(rule);
}
#define NFT_RULE_MAXEXPRS 128
static struct nft_expr_info *info;
static struct nft_rule_trans *
nf_tables_trans_add(struct nft_rule *rule, const struct nft_ctx *ctx)
{
struct nft_rule_trans *rupd;
rupd = kmalloc(sizeof(struct nft_rule_trans), GFP_KERNEL);
if (rupd == NULL)
return NULL;
rupd->chain = ctx->chain;
rupd->table = ctx->table;
rupd->rule = rule;
rupd->family = ctx->afi->family;
rupd->nlh = ctx->nlh;
list_add_tail(&rupd->list, &ctx->net->nft.commit_list);
return rupd;
}
static int nf_tables_newrule(struct sock *nlsk, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const nla[])
{
const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
const struct nft_af_info *afi;
struct net *net = sock_net(skb->sk);
struct nft_table *table;
struct nft_chain *chain;
struct nft_rule *rule, *old_rule = NULL;
struct nft_rule_trans *repl = NULL;
struct nft_expr *expr;
struct nft_ctx ctx;
struct nlattr *tmp;
unsigned int size, i, n;
int err, rem;
bool create;
u64 handle, pos_handle;
create = nlh->nlmsg_flags & NLM_F_CREATE ? true : false;
afi = nf_tables_afinfo_lookup(net, nfmsg->nfgen_family, create);
if (IS_ERR(afi))
return PTR_ERR(afi);
table = nf_tables_table_lookup(afi, nla[NFTA_RULE_TABLE]);
if (IS_ERR(table))
return PTR_ERR(table);
chain = nf_tables_chain_lookup(table, nla[NFTA_RULE_CHAIN]);
if (IS_ERR(chain))
return PTR_ERR(chain);
if (nla[NFTA_RULE_HANDLE]) {
handle = be64_to_cpu(nla_get_be64(nla[NFTA_RULE_HANDLE]));
rule = __nf_tables_rule_lookup(chain, handle);
if (IS_ERR(rule))
return PTR_ERR(rule);
if (nlh->nlmsg_flags & NLM_F_EXCL)
return -EEXIST;
if (nlh->nlmsg_flags & NLM_F_REPLACE)
old_rule = rule;
else
return -EOPNOTSUPP;
} else {
if (!create || nlh->nlmsg_flags & NLM_F_REPLACE)
return -EINVAL;
handle = nf_tables_alloc_handle(table);
}
if (nla[NFTA_RULE_POSITION]) {
if (!(nlh->nlmsg_flags & NLM_F_CREATE))
return -EOPNOTSUPP;
pos_handle = be64_to_cpu(nla_get_be64(nla[NFTA_RULE_POSITION]));
old_rule = __nf_tables_rule_lookup(chain, pos_handle);
if (IS_ERR(old_rule))
return PTR_ERR(old_rule);
}
nft_ctx_init(&ctx, skb, nlh, afi, table, chain, nla);
n = 0;
size = 0;
if (nla[NFTA_RULE_EXPRESSIONS]) {
nla_for_each_nested(tmp, nla[NFTA_RULE_EXPRESSIONS], rem) {
err = -EINVAL;
if (nla_type(tmp) != NFTA_LIST_ELEM)
goto err1;
if (n == NFT_RULE_MAXEXPRS)
goto err1;
err = nf_tables_expr_parse(&ctx, tmp, &info[n]);
if (err < 0)
goto err1;
size += info[n].ops->size;
n++;
}
}
err = -ENOMEM;
rule = kzalloc(sizeof(*rule) + size, GFP_KERNEL);
if (rule == NULL)
goto err1;
nft_rule_activate_next(net, rule);
rule->handle = handle;
rule->dlen = size;
expr = nft_expr_first(rule);
for (i = 0; i < n; i++) {
err = nf_tables_newexpr(&ctx, &info[i], expr);
if (err < 0)
goto err2;
info[i].ops = NULL;
expr = nft_expr_next(expr);
}
if (nlh->nlmsg_flags & NLM_F_REPLACE) {
if (nft_rule_is_active_next(net, old_rule)) {
repl = nf_tables_trans_add(old_rule, &ctx);
if (repl == NULL) {
err = -ENOMEM;
goto err2;
}
nft_rule_disactivate_next(net, old_rule);
list_add_tail(&rule->list, &old_rule->list);
} else {
err = -ENOENT;
goto err2;
}
} else if (nlh->nlmsg_flags & NLM_F_APPEND)
if (old_rule)
list_add_rcu(&rule->list, &old_rule->list);
else
list_add_tail_rcu(&rule->list, &chain->rules);
else {
if (old_rule)
list_add_tail_rcu(&rule->list, &old_rule->list);
else
list_add_rcu(&rule->list, &chain->rules);
}
if (nf_tables_trans_add(rule, &ctx) == NULL) {
err = -ENOMEM;
goto err3;
}
return 0;
err3:
list_del_rcu(&rule->list);
if (repl) {
list_del_rcu(&repl->rule->list);
list_del(&repl->list);
nft_rule_clear(net, repl->rule);
kfree(repl);
}
err2:
nf_tables_rule_destroy(rule);
err1:
for (i = 0; i < n; i++) {
if (info[i].ops != NULL)
module_put(info[i].ops->type->owner);
}
return err;
}
static int
nf_tables_delrule_one(struct nft_ctx *ctx, struct nft_rule *rule)
{
/* You cannot delete the same rule twice */
if (nft_rule_is_active_next(ctx->net, rule)) {
if (nf_tables_trans_add(rule, ctx) == NULL)
return -ENOMEM;
nft_rule_disactivate_next(ctx->net, rule);
return 0;
}
return -ENOENT;
}
static int nf_table_delrule_by_chain(struct nft_ctx *ctx)
{
struct nft_rule *rule;
int err;
list_for_each_entry(rule, &ctx->chain->rules, list) {
err = nf_tables_delrule_one(ctx, rule);
if (err < 0)
return err;
}
return 0;
}
static int nf_tables_delrule(struct sock *nlsk, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const nla[])
{
const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
const struct nft_af_info *afi;
struct net *net = sock_net(skb->sk);
const struct nft_table *table;
struct nft_chain *chain = NULL;
struct nft_rule *rule;
int family = nfmsg->nfgen_family, err = 0;
struct nft_ctx ctx;
afi = nf_tables_afinfo_lookup(net, family, false);
if (IS_ERR(afi))
return PTR_ERR(afi);
table = nf_tables_table_lookup(afi, nla[NFTA_RULE_TABLE]);
if (IS_ERR(table))
return PTR_ERR(table);
if (nla[NFTA_RULE_CHAIN]) {
chain = nf_tables_chain_lookup(table, nla[NFTA_RULE_CHAIN]);
if (IS_ERR(chain))
return PTR_ERR(chain);
}
nft_ctx_init(&ctx, skb, nlh, afi, table, chain, nla);
if (chain) {
if (nla[NFTA_RULE_HANDLE]) {
rule = nf_tables_rule_lookup(chain,
nla[NFTA_RULE_HANDLE]);
if (IS_ERR(rule))
return PTR_ERR(rule);
err = nf_tables_delrule_one(&ctx, rule);
} else {
err = nf_table_delrule_by_chain(&ctx);
}
} else {
list_for_each_entry(chain, &table->chains, list) {
ctx.chain = chain;
err = nf_table_delrule_by_chain(&ctx);
if (err < 0)
break;
}
}
return err;
}
static int nf_tables_commit(struct sk_buff *skb)
{
struct net *net = sock_net(skb->sk);
struct nft_rule_trans *rupd, *tmp;
/* Bump generation counter, invalidate any dump in progress */
net->nft.genctr++;
/* A new generation has just started */
net->nft.gencursor = gencursor_next(net);
/* Make sure all packets have left the previous generation before
* purging old rules.
*/
synchronize_rcu();
list_for_each_entry_safe(rupd, tmp, &net->nft.commit_list, list) {
/* This rule was inactive in the past and just became active.
* Clear the next bit of the genmask since its meaning has
* changed, now it is the future.
*/
if (nft_rule_is_active(net, rupd->rule)) {
nft_rule_clear(net, rupd->rule);
nf_tables_rule_notify(skb, rupd->nlh, rupd->table,
rupd->chain, rupd->rule,
NFT_MSG_NEWRULE, 0,
rupd->family);
list_del(&rupd->list);
kfree(rupd);
continue;
}
/* This rule is in the past, get rid of it */
list_del_rcu(&rupd->rule->list);
nf_tables_rule_notify(skb, rupd->nlh, rupd->table, rupd->chain,
rupd->rule, NFT_MSG_DELRULE, 0,
rupd->family);
}
/* Make sure we don't see any packet traversing old rules */
synchronize_rcu();
/* Now we can safely release unused old rules */
list_for_each_entry_safe(rupd, tmp, &net->nft.commit_list, list) {
nf_tables_rule_destroy(rupd->rule);
list_del(&rupd->list);
kfree(rupd);
}
return 0;
}
static int nf_tables_abort(struct sk_buff *skb)
{
struct net *net = sock_net(skb->sk);
struct nft_rule_trans *rupd, *tmp;
list_for_each_entry_safe(rupd, tmp, &net->nft.commit_list, list) {
if (!nft_rule_is_active_next(net, rupd->rule)) {
nft_rule_clear(net, rupd->rule);
list_del(&rupd->list);
kfree(rupd);
continue;
}
/* This rule is inactive, get rid of it */
list_del_rcu(&rupd->rule->list);
}
/* Make sure we don't see any packet accessing aborted rules */
synchronize_rcu();
list_for_each_entry_safe(rupd, tmp, &net->nft.commit_list, list) {
nf_tables_rule_destroy(rupd->rule);
list_del(&rupd->list);
kfree(rupd);
}
return 0;
}
/*
* Sets
*/
static LIST_HEAD(nf_tables_set_ops);
int nft_register_set(struct nft_set_ops *ops)
{
nfnl_lock(NFNL_SUBSYS_NFTABLES);
list_add_tail(&ops->list, &nf_tables_set_ops);
nfnl_unlock(NFNL_SUBSYS_NFTABLES);
return 0;
}
EXPORT_SYMBOL_GPL(nft_register_set);
void nft_unregister_set(struct nft_set_ops *ops)
{
nfnl_lock(NFNL_SUBSYS_NFTABLES);
list_del(&ops->list);
nfnl_unlock(NFNL_SUBSYS_NFTABLES);
}
EXPORT_SYMBOL_GPL(nft_unregister_set);
static const struct nft_set_ops *nft_select_set_ops(const struct nlattr * const nla[])
{
const struct nft_set_ops *ops;
u32 features;
#ifdef CONFIG_MODULES
if (list_empty(&nf_tables_set_ops)) {
nfnl_unlock(NFNL_SUBSYS_NFTABLES);
request_module("nft-set");
nfnl_lock(NFNL_SUBSYS_NFTABLES);
if (!list_empty(&nf_tables_set_ops))
return ERR_PTR(-EAGAIN);
}
#endif
features = 0;
if (nla[NFTA_SET_FLAGS] != NULL) {
features = ntohl(nla_get_be32(nla[NFTA_SET_FLAGS]));
features &= NFT_SET_INTERVAL | NFT_SET_MAP;
}
// FIXME: implement selection properly
list_for_each_entry(ops, &nf_tables_set_ops, list) {
if ((ops->features & features) != features)
continue;
if (!try_module_get(ops->owner))
continue;
return ops;
}
return ERR_PTR(-EOPNOTSUPP);
}
static const struct nla_policy nft_set_policy[NFTA_SET_MAX + 1] = {
[NFTA_SET_TABLE] = { .type = NLA_STRING },
[NFTA_SET_NAME] = { .type = NLA_STRING },
[NFTA_SET_FLAGS] = { .type = NLA_U32 },
[NFTA_SET_KEY_TYPE] = { .type = NLA_U32 },
[NFTA_SET_KEY_LEN] = { .type = NLA_U32 },
[NFTA_SET_DATA_TYPE] = { .type = NLA_U32 },
[NFTA_SET_DATA_LEN] = { .type = NLA_U32 },
};
static int nft_ctx_init_from_setattr(struct nft_ctx *ctx,
const struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const nla[])
{
struct net *net = sock_net(skb->sk);
const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
const struct nft_af_info *afi = NULL;
const struct nft_table *table = NULL;
if (nfmsg->nfgen_family != NFPROTO_UNSPEC) {
afi = nf_tables_afinfo_lookup(net, nfmsg->nfgen_family, false);
if (IS_ERR(afi))
return PTR_ERR(afi);
}
if (nla[NFTA_SET_TABLE] != NULL) {
if (afi == NULL)
return -EAFNOSUPPORT;
table = nf_tables_table_lookup(afi, nla[NFTA_SET_TABLE]);
if (IS_ERR(table))
return PTR_ERR(table);
}
nft_ctx_init(ctx, skb, nlh, afi, table, NULL, nla);
return 0;
}
struct nft_set *nf_tables_set_lookup(const struct nft_table *table,
const struct nlattr *nla)
{
struct nft_set *set;
if (nla == NULL)
return ERR_PTR(-EINVAL);
list_for_each_entry(set, &table->sets, list) {
if (!nla_strcmp(nla, set->name))
return set;
}
return ERR_PTR(-ENOENT);
}
static int nf_tables_set_alloc_name(struct nft_ctx *ctx, struct nft_set *set,
const char *name)
{
const struct nft_set *i;
const char *p;
unsigned long *inuse;
unsigned int n = 0;
p = strnchr(name, IFNAMSIZ, '%');
if (p != NULL) {
if (p[1] != 'd' || strchr(p + 2, '%'))
return -EINVAL;
inuse = (unsigned long *)get_zeroed_page(GFP_KERNEL);
if (inuse == NULL)
return -ENOMEM;
list_for_each_entry(i, &ctx->table->sets, list) {
int tmp;
if (!sscanf(i->name, name, &tmp))
continue;
if (tmp < 0 || tmp >= BITS_PER_BYTE * PAGE_SIZE)
continue;
set_bit(tmp, inuse);
}
n = find_first_zero_bit(inuse, BITS_PER_BYTE * PAGE_SIZE);
free_page((unsigned long)inuse);
}
snprintf(set->name, sizeof(set->name), name, n);
list_for_each_entry(i, &ctx->table->sets, list) {
if (!strcmp(set->name, i->name))
return -ENFILE;
}
return 0;
}
static int nf_tables_fill_set(struct sk_buff *skb, const struct nft_ctx *ctx,
const struct nft_set *set, u16 event, u16 flags)
{
struct nfgenmsg *nfmsg;
struct nlmsghdr *nlh;
u32 portid = NETLINK_CB(ctx->skb).portid;
u32 seq = ctx->nlh->nlmsg_seq;
event |= NFNL_SUBSYS_NFTABLES << 8;
nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct nfgenmsg),
flags);
if (nlh == NULL)
goto nla_put_failure;
nfmsg = nlmsg_data(nlh);
nfmsg->nfgen_family = ctx->afi->family;
nfmsg->version = NFNETLINK_V0;
nfmsg->res_id = 0;
if (nla_put_string(skb, NFTA_SET_TABLE, ctx->table->name))
goto nla_put_failure;
if (nla_put_string(skb, NFTA_SET_NAME, set->name))
goto nla_put_failure;
if (set->flags != 0)
if (nla_put_be32(skb, NFTA_SET_FLAGS, htonl(set->flags)))
goto nla_put_failure;
if (nla_put_be32(skb, NFTA_SET_KEY_TYPE, htonl(set->ktype)))
goto nla_put_failure;
if (nla_put_be32(skb, NFTA_SET_KEY_LEN, htonl(set->klen)))
goto nla_put_failure;
if (set->flags & NFT_SET_MAP) {
if (nla_put_be32(skb, NFTA_SET_DATA_TYPE, htonl(set->dtype)))
goto nla_put_failure;
if (nla_put_be32(skb, NFTA_SET_DATA_LEN, htonl(set->dlen)))
goto nla_put_failure;
}
return nlmsg_end(skb, nlh);
nla_put_failure:
nlmsg_trim(skb, nlh);
return -1;
}
static int nf_tables_set_notify(const struct nft_ctx *ctx,
const struct nft_set *set,
int event)
{
struct sk_buff *skb;
u32 portid = NETLINK_CB(ctx->skb).portid;
bool report;
int err;
report = nlmsg_report(ctx->nlh);
if (!report && !nfnetlink_has_listeners(ctx->net, NFNLGRP_NFTABLES))
return 0;
err = -ENOBUFS;
skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
if (skb == NULL)
goto err;
err = nf_tables_fill_set(skb, ctx, set, event, 0);
if (err < 0) {
kfree_skb(skb);
goto err;
}
err = nfnetlink_send(skb, ctx->net, portid, NFNLGRP_NFTABLES, report,
GFP_KERNEL);
err:
if (err < 0)
nfnetlink_set_err(ctx->net, portid, NFNLGRP_NFTABLES, err);
return err;
}
static int nf_tables_dump_sets_table(struct nft_ctx *ctx, struct sk_buff *skb,
struct netlink_callback *cb)
{
const struct nft_set *set;
unsigned int idx = 0, s_idx = cb->args[0];
if (cb->args[1])
return skb->len;
list_for_each_entry(set, &ctx->table->sets, list) {
if (idx < s_idx)
goto cont;
if (nf_tables_fill_set(skb, ctx, set, NFT_MSG_NEWSET,
NLM_F_MULTI) < 0) {
cb->args[0] = idx;
goto done;
}
cont:
idx++;
}
cb->args[1] = 1;
done:
return skb->len;
}
static int nf_tables_dump_sets_family(struct nft_ctx *ctx, struct sk_buff *skb,
struct netlink_callback *cb)
{
const struct nft_set *set;
unsigned int idx, s_idx = cb->args[0];
struct nft_table *table, *cur_table = (struct nft_table *)cb->args[2];
if (cb->args[1])
return skb->len;
list_for_each_entry(table, &ctx->afi->tables, list) {
if (cur_table) {
if (cur_table != table)
continue;
cur_table = NULL;
}
ctx->table = table;
idx = 0;
list_for_each_entry(set, &ctx->table->sets, list) {
if (idx < s_idx)
goto cont;
if (nf_tables_fill_set(skb, ctx, set, NFT_MSG_NEWSET,
NLM_F_MULTI) < 0) {
cb->args[0] = idx;
cb->args[2] = (unsigned long) table;
goto done;
}
cont:
idx++;
}
}
cb->args[1] = 1;
done:
return skb->len;
}
static int nf_tables_dump_sets_all(struct nft_ctx *ctx, struct sk_buff *skb,
struct netlink_callback *cb)
{
const struct nft_set *set;
unsigned int idx, s_idx = cb->args[0];
const struct nft_af_info *afi;
struct nft_table *table, *cur_table = (struct nft_table *)cb->args[2];
struct net *net = sock_net(skb->sk);
int cur_family = cb->args[3];
if (cb->args[1])
return skb->len;
list_for_each_entry(afi, &net->nft.af_info, list) {
if (cur_family) {
if (afi->family != cur_family)
continue;
cur_family = 0;
}
list_for_each_entry(table, &afi->tables, list) {
if (cur_table) {
if (cur_table != table)
continue;
cur_table = NULL;
}
ctx->table = table;
ctx->afi = afi;
idx = 0;
list_for_each_entry(set, &ctx->table->sets, list) {
if (idx < s_idx)
goto cont;
if (nf_tables_fill_set(skb, ctx, set,
NFT_MSG_NEWSET,
NLM_F_MULTI) < 0) {
cb->args[0] = idx;
cb->args[2] = (unsigned long) table;
cb->args[3] = afi->family;
goto done;
}
cont:
idx++;
}
if (s_idx)
s_idx = 0;
}
}
cb->args[1] = 1;
done:
return skb->len;
}
static int nf_tables_dump_sets(struct sk_buff *skb, struct netlink_callback *cb)
{
const struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
struct nlattr *nla[NFTA_SET_MAX + 1];
struct nft_ctx ctx;
int err, ret;
err = nlmsg_parse(cb->nlh, sizeof(*nfmsg), nla, NFTA_SET_MAX,
nft_set_policy);
if (err < 0)
return err;
err = nft_ctx_init_from_setattr(&ctx, cb->skb, cb->nlh, (void *)nla);
if (err < 0)
return err;
if (ctx.table == NULL) {
if (ctx.afi == NULL)
ret = nf_tables_dump_sets_all(&ctx, skb, cb);
else
ret = nf_tables_dump_sets_family(&ctx, skb, cb);
} else
ret = nf_tables_dump_sets_table(&ctx, skb, cb);
return ret;
}
static int nf_tables_getset(struct sock *nlsk, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const nla[])
{
const struct nft_set *set;
struct nft_ctx ctx;
struct sk_buff *skb2;
const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
int err;
/* Verify existance before starting dump */
err = nft_ctx_init_from_setattr(&ctx, skb, nlh, nla);
if (err < 0)
return err;
if (nlh->nlmsg_flags & NLM_F_DUMP) {
struct netlink_dump_control c = {
.dump = nf_tables_dump_sets,
};
return netlink_dump_start(nlsk, skb, nlh, &c);
}
/* Only accept unspec with dump */
if (nfmsg->nfgen_family == NFPROTO_UNSPEC)
return -EAFNOSUPPORT;
set = nf_tables_set_lookup(ctx.table, nla[NFTA_SET_NAME]);
if (IS_ERR(set))
return PTR_ERR(set);
skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
if (skb2 == NULL)
return -ENOMEM;
err = nf_tables_fill_set(skb2, &ctx, set, NFT_MSG_NEWSET, 0);
if (err < 0)
goto err;
return nlmsg_unicast(nlsk, skb2, NETLINK_CB(skb).portid);
err:
kfree_skb(skb2);
return err;
}
static int nf_tables_newset(struct sock *nlsk, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const nla[])
{
const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
const struct nft_set_ops *ops;
const struct nft_af_info *afi;
struct net *net = sock_net(skb->sk);
struct nft_table *table;
struct nft_set *set;
struct nft_ctx ctx;
char name[IFNAMSIZ];
unsigned int size;
bool create;
u32 ktype, klen, dlen, dtype, flags;
int err;
if (nla[NFTA_SET_TABLE] == NULL ||
nla[NFTA_SET_NAME] == NULL ||
nla[NFTA_SET_KEY_LEN] == NULL)
return -EINVAL;
ktype = NFT_DATA_VALUE;
if (nla[NFTA_SET_KEY_TYPE] != NULL) {
ktype = ntohl(nla_get_be32(nla[NFTA_SET_KEY_TYPE]));
if ((ktype & NFT_DATA_RESERVED_MASK) == NFT_DATA_RESERVED_MASK)
return -EINVAL;
}
klen = ntohl(nla_get_be32(nla[NFTA_SET_KEY_LEN]));
if (klen == 0 || klen > FIELD_SIZEOF(struct nft_data, data))
return -EINVAL;
flags = 0;
if (nla[NFTA_SET_FLAGS] != NULL) {
flags = ntohl(nla_get_be32(nla[NFTA_SET_FLAGS]));
if (flags & ~(NFT_SET_ANONYMOUS | NFT_SET_CONSTANT |
NFT_SET_INTERVAL | NFT_SET_MAP))
return -EINVAL;
}
dtype = 0;
dlen = 0;
if (nla[NFTA_SET_DATA_TYPE] != NULL) {
if (!(flags & NFT_SET_MAP))
return -EINVAL;
dtype = ntohl(nla_get_be32(nla[NFTA_SET_DATA_TYPE]));
if ((dtype & NFT_DATA_RESERVED_MASK) == NFT_DATA_RESERVED_MASK &&
dtype != NFT_DATA_VERDICT)
return -EINVAL;
if (dtype != NFT_DATA_VERDICT) {
if (nla[NFTA_SET_DATA_LEN] == NULL)
return -EINVAL;
dlen = ntohl(nla_get_be32(nla[NFTA_SET_DATA_LEN]));
if (dlen == 0 ||
dlen > FIELD_SIZEOF(struct nft_data, data))
return -EINVAL;
} else
dlen = sizeof(struct nft_data);
} else if (flags & NFT_SET_MAP)
return -EINVAL;
create = nlh->nlmsg_flags & NLM_F_CREATE ? true : false;
afi = nf_tables_afinfo_lookup(net, nfmsg->nfgen_family, create);
if (IS_ERR(afi))
return PTR_ERR(afi);
table = nf_tables_table_lookup(afi, nla[NFTA_SET_TABLE]);
if (IS_ERR(table))
return PTR_ERR(table);
nft_ctx_init(&ctx, skb, nlh, afi, table, NULL, nla);
set = nf_tables_set_lookup(table, nla[NFTA_SET_NAME]);
if (IS_ERR(set)) {
if (PTR_ERR(set) != -ENOENT)
return PTR_ERR(set);
set = NULL;
}
if (set != NULL) {
if (nlh->nlmsg_flags & NLM_F_EXCL)
return -EEXIST;
if (nlh->nlmsg_flags & NLM_F_REPLACE)
return -EOPNOTSUPP;
return 0;
}
if (!(nlh->nlmsg_flags & NLM_F_CREATE))
return -ENOENT;
ops = nft_select_set_ops(nla);
if (IS_ERR(ops))
return PTR_ERR(ops);
size = 0;
if (ops->privsize != NULL)
size = ops->privsize(nla);
err = -ENOMEM;
set = kzalloc(sizeof(*set) + size, GFP_KERNEL);
if (set == NULL)
goto err1;
nla_strlcpy(name, nla[NFTA_SET_NAME], sizeof(set->name));
err = nf_tables_set_alloc_name(&ctx, set, name);
if (err < 0)
goto err2;
INIT_LIST_HEAD(&set->bindings);
set->ops = ops;
set->ktype = ktype;
set->klen = klen;
set->dtype = dtype;
set->dlen = dlen;
set->flags = flags;
err = ops->init(set, nla);
if (err < 0)
goto err2;
list_add_tail(&set->list, &table->sets);
nf_tables_set_notify(&ctx, set, NFT_MSG_NEWSET);
return 0;
err2:
kfree(set);
err1:
module_put(ops->owner);
return err;
}
static void nf_tables_set_destroy(const struct nft_ctx *ctx, struct nft_set *set)
{
list_del(&set->list);
if (!(set->flags & NFT_SET_ANONYMOUS))
nf_tables_set_notify(ctx, set, NFT_MSG_DELSET);
set->ops->destroy(set);
module_put(set->ops->owner);
kfree(set);
}
static int nf_tables_delset(struct sock *nlsk, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const nla[])
{
const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
struct nft_set *set;
struct nft_ctx ctx;
int err;
if (nfmsg->nfgen_family == NFPROTO_UNSPEC)
return -EAFNOSUPPORT;
if (nla[NFTA_SET_TABLE] == NULL)
return -EINVAL;
err = nft_ctx_init_from_setattr(&ctx, skb, nlh, nla);
if (err < 0)
return err;
set = nf_tables_set_lookup(ctx.table, nla[NFTA_SET_NAME]);
if (IS_ERR(set))
return PTR_ERR(set);
if (!list_empty(&set->bindings))
return -EBUSY;
nf_tables_set_destroy(&ctx, set);
return 0;
}
static int nf_tables_bind_check_setelem(const struct nft_ctx *ctx,
const struct nft_set *set,
const struct nft_set_iter *iter,
const struct nft_set_elem *elem)
{
enum nft_registers dreg;
dreg = nft_type_to_reg(set->dtype);
return nft_validate_data_load(ctx, dreg, &elem->data,
set->dtype == NFT_DATA_VERDICT ?
NFT_DATA_VERDICT : NFT_DATA_VALUE);
}
int nf_tables_bind_set(const struct nft_ctx *ctx, struct nft_set *set,
struct nft_set_binding *binding)
{
struct nft_set_binding *i;
struct nft_set_iter iter;
if (!list_empty(&set->bindings) && set->flags & NFT_SET_ANONYMOUS)
return -EBUSY;
if (set->flags & NFT_SET_MAP) {
/* If the set is already bound to the same chain all
* jumps are already validated for that chain.
*/
list_for_each_entry(i, &set->bindings, list) {
if (i->chain == binding->chain)
goto bind;
}
iter.skip = 0;
iter.count = 0;
iter.err = 0;
iter.fn = nf_tables_bind_check_setelem;
set->ops->walk(ctx, set, &iter);
if (iter.err < 0) {
/* Destroy anonymous sets if binding fails */
if (set->flags & NFT_SET_ANONYMOUS)
nf_tables_set_destroy(ctx, set);
return iter.err;
}
}
bind:
binding->chain = ctx->chain;
list_add_tail(&binding->list, &set->bindings);
return 0;
}
void nf_tables_unbind_set(const struct nft_ctx *ctx, struct nft_set *set,
struct nft_set_binding *binding)
{
list_del(&binding->list);
if (list_empty(&set->bindings) && set->flags & NFT_SET_ANONYMOUS)
nf_tables_set_destroy(ctx, set);
}
/*
* Set elements
*/
static const struct nla_policy nft_set_elem_policy[NFTA_SET_ELEM_MAX + 1] = {
[NFTA_SET_ELEM_KEY] = { .type = NLA_NESTED },
[NFTA_SET_ELEM_DATA] = { .type = NLA_NESTED },
[NFTA_SET_ELEM_FLAGS] = { .type = NLA_U32 },
};
static const struct nla_policy nft_set_elem_list_policy[NFTA_SET_ELEM_LIST_MAX + 1] = {
[NFTA_SET_ELEM_LIST_TABLE] = { .type = NLA_STRING },
[NFTA_SET_ELEM_LIST_SET] = { .type = NLA_STRING },
[NFTA_SET_ELEM_LIST_ELEMENTS] = { .type = NLA_NESTED },
};
static int nft_ctx_init_from_elemattr(struct nft_ctx *ctx,
const struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const nla[])
{
const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
const struct nft_af_info *afi;
const struct nft_table *table;
struct net *net = sock_net(skb->sk);
afi = nf_tables_afinfo_lookup(net, nfmsg->nfgen_family, false);
if (IS_ERR(afi))
return PTR_ERR(afi);
table = nf_tables_table_lookup(afi, nla[NFTA_SET_ELEM_LIST_TABLE]);
if (IS_ERR(table))
return PTR_ERR(table);
nft_ctx_init(ctx, skb, nlh, afi, table, NULL, nla);
return 0;
}
static int nf_tables_fill_setelem(struct sk_buff *skb,
const struct nft_set *set,
const struct nft_set_elem *elem)
{
unsigned char *b = skb_tail_pointer(skb);
struct nlattr *nest;
nest = nla_nest_start(skb, NFTA_LIST_ELEM);
if (nest == NULL)
goto nla_put_failure;
if (nft_data_dump(skb, NFTA_SET_ELEM_KEY, &elem->key, NFT_DATA_VALUE,
set->klen) < 0)
goto nla_put_failure;
if (set->flags & NFT_SET_MAP &&
!(elem->flags & NFT_SET_ELEM_INTERVAL_END) &&
nft_data_dump(skb, NFTA_SET_ELEM_DATA, &elem->data,
set->dtype == NFT_DATA_VERDICT ? NFT_DATA_VERDICT : NFT_DATA_VALUE,
set->dlen) < 0)
goto nla_put_failure;
if (elem->flags != 0)
if (nla_put_be32(skb, NFTA_SET_ELEM_FLAGS, htonl(elem->flags)))
goto nla_put_failure;
nla_nest_end(skb, nest);
return 0;
nla_put_failure:
nlmsg_trim(skb, b);
return -EMSGSIZE;
}
struct nft_set_dump_args {
const struct netlink_callback *cb;
struct nft_set_iter iter;
struct sk_buff *skb;
};
static int nf_tables_dump_setelem(const struct nft_ctx *ctx,
const struct nft_set *set,
const struct nft_set_iter *iter,
const struct nft_set_elem *elem)
{
struct nft_set_dump_args *args;
args = container_of(iter, struct nft_set_dump_args, iter);
return nf_tables_fill_setelem(args->skb, set, elem);
}
static int nf_tables_dump_set(struct sk_buff *skb, struct netlink_callback *cb)
{
const struct nft_set *set;
struct nft_set_dump_args args;
struct nft_ctx ctx;
struct nlattr *nla[NFTA_SET_ELEM_LIST_MAX + 1];
struct nfgenmsg *nfmsg;
struct nlmsghdr *nlh;
struct nlattr *nest;
u32 portid, seq;
int event, err;
err = nlmsg_parse(cb->nlh, sizeof(struct nfgenmsg), nla,
NFTA_SET_ELEM_LIST_MAX, nft_set_elem_list_policy);
if (err < 0)
return err;
err = nft_ctx_init_from_elemattr(&ctx, cb->skb, cb->nlh, (void *)nla);
if (err < 0)
return err;
set = nf_tables_set_lookup(ctx.table, nla[NFTA_SET_ELEM_LIST_SET]);
if (IS_ERR(set))
return PTR_ERR(set);
event = NFT_MSG_NEWSETELEM;
event |= NFNL_SUBSYS_NFTABLES << 8;
portid = NETLINK_CB(cb->skb).portid;
seq = cb->nlh->nlmsg_seq;
nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct nfgenmsg),
NLM_F_MULTI);
if (nlh == NULL)
goto nla_put_failure;
nfmsg = nlmsg_data(nlh);
nfmsg->nfgen_family = NFPROTO_UNSPEC;
nfmsg->version = NFNETLINK_V0;
nfmsg->res_id = 0;
if (nla_put_string(skb, NFTA_SET_ELEM_LIST_TABLE, ctx.table->name))
goto nla_put_failure;
if (nla_put_string(skb, NFTA_SET_ELEM_LIST_SET, set->name))
goto nla_put_failure;
nest = nla_nest_start(skb, NFTA_SET_ELEM_LIST_ELEMENTS);
if (nest == NULL)
goto nla_put_failure;
args.cb = cb;
args.skb = skb;
args.iter.skip = cb->args[0];
args.iter.count = 0;
args.iter.err = 0;
args.iter.fn = nf_tables_dump_setelem;
set->ops->walk(&ctx, set, &args.iter);
nla_nest_end(skb, nest);
nlmsg_end(skb, nlh);
if (args.iter.err && args.iter.err != -EMSGSIZE)
return args.iter.err;
if (args.iter.count == cb->args[0])
return 0;
cb->args[0] = args.iter.count;
return skb->len;
nla_put_failure:
return -ENOSPC;
}
static int nf_tables_getsetelem(struct sock *nlsk, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const nla[])
{
const struct nft_set *set;
struct nft_ctx ctx;
int err;
err = nft_ctx_init_from_elemattr(&ctx, skb, nlh, nla);
if (err < 0)
return err;
set = nf_tables_set_lookup(ctx.table, nla[NFTA_SET_ELEM_LIST_SET]);
if (IS_ERR(set))
return PTR_ERR(set);
if (nlh->nlmsg_flags & NLM_F_DUMP) {
struct netlink_dump_control c = {
.dump = nf_tables_dump_set,
};
return netlink_dump_start(nlsk, skb, nlh, &c);
}
return -EOPNOTSUPP;
}
static int nft_add_set_elem(const struct nft_ctx *ctx, struct nft_set *set,
const struct nlattr *attr)
{
struct nlattr *nla[NFTA_SET_ELEM_MAX + 1];
struct nft_data_desc d1, d2;
struct nft_set_elem elem;
struct nft_set_binding *binding;
enum nft_registers dreg;
int err;
err = nla_parse_nested(nla, NFTA_SET_ELEM_MAX, attr,
nft_set_elem_policy);
if (err < 0)
return err;
if (nla[NFTA_SET_ELEM_KEY] == NULL)
return -EINVAL;
elem.flags = 0;
if (nla[NFTA_SET_ELEM_FLAGS] != NULL) {
elem.flags = ntohl(nla_get_be32(nla[NFTA_SET_ELEM_FLAGS]));
if (elem.flags & ~NFT_SET_ELEM_INTERVAL_END)
return -EINVAL;
}
if (set->flags & NFT_SET_MAP) {
if (nla[NFTA_SET_ELEM_DATA] == NULL &&
!(elem.flags & NFT_SET_ELEM_INTERVAL_END))
return -EINVAL;
if (nla[NFTA_SET_ELEM_DATA] != NULL &&
elem.flags & NFT_SET_ELEM_INTERVAL_END)
return -EINVAL;
} else {
if (nla[NFTA_SET_ELEM_DATA] != NULL)
return -EINVAL;
}
err = nft_data_init(ctx, &elem.key, &d1, nla[NFTA_SET_ELEM_KEY]);
if (err < 0)
goto err1;
err = -EINVAL;
if (d1.type != NFT_DATA_VALUE || d1.len != set->klen)
goto err2;
err = -EEXIST;
if (set->ops->get(set, &elem) == 0)
goto err2;
if (nla[NFTA_SET_ELEM_DATA] != NULL) {
err = nft_data_init(ctx, &elem.data, &d2, nla[NFTA_SET_ELEM_DATA]);
if (err < 0)
goto err2;
err = -EINVAL;
if (set->dtype != NFT_DATA_VERDICT && d2.len != set->dlen)
goto err3;
dreg = nft_type_to_reg(set->dtype);
list_for_each_entry(binding, &set->bindings, list) {
struct nft_ctx bind_ctx = {
.afi = ctx->afi,
.table = ctx->table,
.chain = binding->chain,
};
err = nft_validate_data_load(&bind_ctx, dreg,
&elem.data, d2.type);
if (err < 0)
goto err3;
}
}
err = set->ops->insert(set, &elem);
if (err < 0)
goto err3;
return 0;
err3:
if (nla[NFTA_SET_ELEM_DATA] != NULL)
nft_data_uninit(&elem.data, d2.type);
err2:
nft_data_uninit(&elem.key, d1.type);
err1:
return err;
}
static int nf_tables_newsetelem(struct sock *nlsk, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const nla[])
{
const struct nlattr *attr;
struct nft_set *set;
struct nft_ctx ctx;
int rem, err;
err = nft_ctx_init_from_elemattr(&ctx, skb, nlh, nla);
if (err < 0)
return err;
set = nf_tables_set_lookup(ctx.table, nla[NFTA_SET_ELEM_LIST_SET]);
if (IS_ERR(set))
return PTR_ERR(set);
if (!list_empty(&set->bindings) && set->flags & NFT_SET_CONSTANT)
return -EBUSY;
nla_for_each_nested(attr, nla[NFTA_SET_ELEM_LIST_ELEMENTS], rem) {
err = nft_add_set_elem(&ctx, set, attr);
if (err < 0)
return err;
}
return 0;
}
static int nft_del_setelem(const struct nft_ctx *ctx, struct nft_set *set,
const struct nlattr *attr)
{
struct nlattr *nla[NFTA_SET_ELEM_MAX + 1];
struct nft_data_desc desc;
struct nft_set_elem elem;
int err;
err = nla_parse_nested(nla, NFTA_SET_ELEM_MAX, attr,
nft_set_elem_policy);
if (err < 0)
goto err1;
err = -EINVAL;
if (nla[NFTA_SET_ELEM_KEY] == NULL)
goto err1;
err = nft_data_init(ctx, &elem.key, &desc, nla[NFTA_SET_ELEM_KEY]);
if (err < 0)
goto err1;
err = -EINVAL;
if (desc.type != NFT_DATA_VALUE || desc.len != set->klen)
goto err2;
err = set->ops->get(set, &elem);
if (err < 0)
goto err2;
set->ops->remove(set, &elem);
nft_data_uninit(&elem.key, NFT_DATA_VALUE);
if (set->flags & NFT_SET_MAP)
nft_data_uninit(&elem.data, set->dtype);
err2:
nft_data_uninit(&elem.key, desc.type);
err1:
return err;
}
static int nf_tables_delsetelem(struct sock *nlsk, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const nla[])
{
const struct nlattr *attr;
struct nft_set *set;
struct nft_ctx ctx;
int rem, err;
err = nft_ctx_init_from_elemattr(&ctx, skb, nlh, nla);
if (err < 0)
return err;
set = nf_tables_set_lookup(ctx.table, nla[NFTA_SET_ELEM_LIST_SET]);
if (IS_ERR(set))
return PTR_ERR(set);
if (!list_empty(&set->bindings) && set->flags & NFT_SET_CONSTANT)
return -EBUSY;
nla_for_each_nested(attr, nla[NFTA_SET_ELEM_LIST_ELEMENTS], rem) {
err = nft_del_setelem(&ctx, set, attr);
if (err < 0)
return err;
}
return 0;
}
static const struct nfnl_callback nf_tables_cb[NFT_MSG_MAX] = {
[NFT_MSG_NEWTABLE] = {
.call = nf_tables_newtable,
.attr_count = NFTA_TABLE_MAX,
.policy = nft_table_policy,
},
[NFT_MSG_GETTABLE] = {
.call = nf_tables_gettable,
.attr_count = NFTA_TABLE_MAX,
.policy = nft_table_policy,
},
[NFT_MSG_DELTABLE] = {
.call = nf_tables_deltable,
.attr_count = NFTA_TABLE_MAX,
.policy = nft_table_policy,
},
[NFT_MSG_NEWCHAIN] = {
.call = nf_tables_newchain,
.attr_count = NFTA_CHAIN_MAX,
.policy = nft_chain_policy,
},
[NFT_MSG_GETCHAIN] = {
.call = nf_tables_getchain,
.attr_count = NFTA_CHAIN_MAX,
.policy = nft_chain_policy,
},
[NFT_MSG_DELCHAIN] = {
.call = nf_tables_delchain,
.attr_count = NFTA_CHAIN_MAX,
.policy = nft_chain_policy,
},
[NFT_MSG_NEWRULE] = {
.call_batch = nf_tables_newrule,
.attr_count = NFTA_RULE_MAX,
.policy = nft_rule_policy,
},
[NFT_MSG_GETRULE] = {
.call = nf_tables_getrule,
.attr_count = NFTA_RULE_MAX,
.policy = nft_rule_policy,
},
[NFT_MSG_DELRULE] = {
.call_batch = nf_tables_delrule,
.attr_count = NFTA_RULE_MAX,
.policy = nft_rule_policy,
},
[NFT_MSG_NEWSET] = {
.call = nf_tables_newset,
.attr_count = NFTA_SET_MAX,
.policy = nft_set_policy,
},
[NFT_MSG_GETSET] = {
.call = nf_tables_getset,
.attr_count = NFTA_SET_MAX,
.policy = nft_set_policy,
},
[NFT_MSG_DELSET] = {
.call = nf_tables_delset,
.attr_count = NFTA_SET_MAX,
.policy = nft_set_policy,
},
[NFT_MSG_NEWSETELEM] = {
.call = nf_tables_newsetelem,
.attr_count = NFTA_SET_ELEM_LIST_MAX,
.policy = nft_set_elem_list_policy,
},
[NFT_MSG_GETSETELEM] = {
.call = nf_tables_getsetelem,
.attr_count = NFTA_SET_ELEM_LIST_MAX,
.policy = nft_set_elem_list_policy,
},
[NFT_MSG_DELSETELEM] = {
.call = nf_tables_delsetelem,
.attr_count = NFTA_SET_ELEM_LIST_MAX,
.policy = nft_set_elem_list_policy,
},
};
static const struct nfnetlink_subsystem nf_tables_subsys = {
.name = "nf_tables",
.subsys_id = NFNL_SUBSYS_NFTABLES,
.cb_count = NFT_MSG_MAX,
.cb = nf_tables_cb,
.commit = nf_tables_commit,
.abort = nf_tables_abort,
};
/*
* Loop detection - walk through the ruleset beginning at the destination chain
* of a new jump until either the source chain is reached (loop) or all
* reachable chains have been traversed.
*
* The loop check is performed whenever a new jump verdict is added to an
* expression or verdict map or a verdict map is bound to a new chain.
*/
static int nf_tables_check_loops(const struct nft_ctx *ctx,
const struct nft_chain *chain);
static int nf_tables_loop_check_setelem(const struct nft_ctx *ctx,
const struct nft_set *set,
const struct nft_set_iter *iter,
const struct nft_set_elem *elem)
{
if (elem->flags & NFT_SET_ELEM_INTERVAL_END)
return 0;
switch (elem->data.verdict) {
case NFT_JUMP:
case NFT_GOTO:
return nf_tables_check_loops(ctx, elem->data.chain);
default:
return 0;
}
}
static int nf_tables_check_loops(const struct nft_ctx *ctx,
const struct nft_chain *chain)
{
const struct nft_rule *rule;
const struct nft_expr *expr, *last;
const struct nft_set *set;
struct nft_set_binding *binding;
struct nft_set_iter iter;
if (ctx->chain == chain)
return -ELOOP;
list_for_each_entry(rule, &chain->rules, list) {
nft_rule_for_each_expr(expr, last, rule) {
const struct nft_data *data = NULL;
int err;
if (!expr->ops->validate)
continue;
err = expr->ops->validate(ctx, expr, &data);
if (err < 0)
return err;
if (data == NULL)
continue;
switch (data->verdict) {
case NFT_JUMP:
case NFT_GOTO:
err = nf_tables_check_loops(ctx, data->chain);
if (err < 0)
return err;
default:
break;
}
}
}
list_for_each_entry(set, &ctx->table->sets, list) {
if (!(set->flags & NFT_SET_MAP) ||
set->dtype != NFT_DATA_VERDICT)
continue;
list_for_each_entry(binding, &set->bindings, list) {
if (binding->chain != chain)
continue;
iter.skip = 0;
iter.count = 0;
iter.err = 0;
iter.fn = nf_tables_loop_check_setelem;
set->ops->walk(ctx, set, &iter);
if (iter.err < 0)
return iter.err;
}
}
return 0;
}
/**
* nft_validate_input_register - validate an expressions' input register
*
* @reg: the register number
*
* Validate that the input register is one of the general purpose
* registers.
*/
int nft_validate_input_register(enum nft_registers reg)
{
if (reg <= NFT_REG_VERDICT)
return -EINVAL;
if (reg > NFT_REG_MAX)
return -ERANGE;
return 0;
}
EXPORT_SYMBOL_GPL(nft_validate_input_register);
/**
* nft_validate_output_register - validate an expressions' output register
*
* @reg: the register number
*
* Validate that the output register is one of the general purpose
* registers or the verdict register.
*/
int nft_validate_output_register(enum nft_registers reg)
{
if (reg < NFT_REG_VERDICT)
return -EINVAL;
if (reg > NFT_REG_MAX)
return -ERANGE;
return 0;
}
EXPORT_SYMBOL_GPL(nft_validate_output_register);
/**
* nft_validate_data_load - validate an expressions' data load
*
* @ctx: context of the expression performing the load
* @reg: the destination register number
* @data: the data to load
* @type: the data type
*
* Validate that a data load uses the appropriate data type for
* the destination register. A value of NULL for the data means
* that its runtime gathered data, which is always of type
* NFT_DATA_VALUE.
*/
int nft_validate_data_load(const struct nft_ctx *ctx, enum nft_registers reg,
const struct nft_data *data,
enum nft_data_types type)
{
int err;
switch (reg) {
case NFT_REG_VERDICT:
if (data == NULL || type != NFT_DATA_VERDICT)
return -EINVAL;
if (data->verdict == NFT_GOTO || data->verdict == NFT_JUMP) {
err = nf_tables_check_loops(ctx, data->chain);
if (err < 0)
return err;
if (ctx->chain->level + 1 > data->chain->level) {
if (ctx->chain->level + 1 == NFT_JUMP_STACK_SIZE)
return -EMLINK;
data->chain->level = ctx->chain->level + 1;
}
}
return 0;
default:
if (data != NULL && type != NFT_DATA_VALUE)
return -EINVAL;
return 0;
}
}
EXPORT_SYMBOL_GPL(nft_validate_data_load);
static const struct nla_policy nft_verdict_policy[NFTA_VERDICT_MAX + 1] = {
[NFTA_VERDICT_CODE] = { .type = NLA_U32 },
[NFTA_VERDICT_CHAIN] = { .type = NLA_STRING,
.len = NFT_CHAIN_MAXNAMELEN - 1 },
};
static int nft_verdict_init(const struct nft_ctx *ctx, struct nft_data *data,
struct nft_data_desc *desc, const struct nlattr *nla)
{
struct nlattr *tb[NFTA_VERDICT_MAX + 1];
struct nft_chain *chain;
int err;
err = nla_parse_nested(tb, NFTA_VERDICT_MAX, nla, nft_verdict_policy);
if (err < 0)
return err;
if (!tb[NFTA_VERDICT_CODE])
return -EINVAL;
data->verdict = ntohl(nla_get_be32(tb[NFTA_VERDICT_CODE]));
switch (data->verdict) {
case NF_ACCEPT:
case NF_DROP:
case NF_QUEUE:
case NFT_CONTINUE:
case NFT_BREAK:
case NFT_RETURN:
desc->len = sizeof(data->verdict);
break;
case NFT_JUMP:
case NFT_GOTO:
if (!tb[NFTA_VERDICT_CHAIN])
return -EINVAL;
chain = nf_tables_chain_lookup(ctx->table,
tb[NFTA_VERDICT_CHAIN]);
if (IS_ERR(chain))
return PTR_ERR(chain);
if (chain->flags & NFT_BASE_CHAIN)
return -EOPNOTSUPP;
chain->use++;
data->chain = chain;
desc->len = sizeof(data);
break;
default:
return -EINVAL;
}
desc->type = NFT_DATA_VERDICT;
return 0;
}
static void nft_verdict_uninit(const struct nft_data *data)
{
switch (data->verdict) {
case NFT_JUMP:
case NFT_GOTO:
data->chain->use--;
break;
}
}
static int nft_verdict_dump(struct sk_buff *skb, const struct nft_data *data)
{
struct nlattr *nest;
nest = nla_nest_start(skb, NFTA_DATA_VERDICT);
if (!nest)
goto nla_put_failure;
if (nla_put_be32(skb, NFTA_VERDICT_CODE, htonl(data->verdict)))
goto nla_put_failure;
switch (data->verdict) {
case NFT_JUMP:
case NFT_GOTO:
if (nla_put_string(skb, NFTA_VERDICT_CHAIN, data->chain->name))
goto nla_put_failure;
}
nla_nest_end(skb, nest);
return 0;
nla_put_failure:
return -1;
}
static int nft_value_init(const struct nft_ctx *ctx, struct nft_data *data,
struct nft_data_desc *desc, const struct nlattr *nla)
{
unsigned int len;
len = nla_len(nla);
if (len == 0)
return -EINVAL;
if (len > sizeof(data->data))
return -EOVERFLOW;
nla_memcpy(data->data, nla, sizeof(data->data));
desc->type = NFT_DATA_VALUE;
desc->len = len;
return 0;
}
static int nft_value_dump(struct sk_buff *skb, const struct nft_data *data,
unsigned int len)
{
return nla_put(skb, NFTA_DATA_VALUE, len, data->data);
}
static const struct nla_policy nft_data_policy[NFTA_DATA_MAX + 1] = {
[NFTA_DATA_VALUE] = { .type = NLA_BINARY,
.len = FIELD_SIZEOF(struct nft_data, data) },
[NFTA_DATA_VERDICT] = { .type = NLA_NESTED },
};
/**
* nft_data_init - parse nf_tables data netlink attributes
*
* @ctx: context of the expression using the data
* @data: destination struct nft_data
* @desc: data description
* @nla: netlink attribute containing data
*
* Parse the netlink data attributes and initialize a struct nft_data.
* The type and length of data are returned in the data description.
*
* The caller can indicate that it only wants to accept data of type
* NFT_DATA_VALUE by passing NULL for the ctx argument.
*/
int nft_data_init(const struct nft_ctx *ctx, struct nft_data *data,
struct nft_data_desc *desc, const struct nlattr *nla)
{
struct nlattr *tb[NFTA_DATA_MAX + 1];
int err;
err = nla_parse_nested(tb, NFTA_DATA_MAX, nla, nft_data_policy);
if (err < 0)
return err;
if (tb[NFTA_DATA_VALUE])
return nft_value_init(ctx, data, desc, tb[NFTA_DATA_VALUE]);
if (tb[NFTA_DATA_VERDICT] && ctx != NULL)
return nft_verdict_init(ctx, data, desc, tb[NFTA_DATA_VERDICT]);
return -EINVAL;
}
EXPORT_SYMBOL_GPL(nft_data_init);
/**
* nft_data_uninit - release a nft_data item
*
* @data: struct nft_data to release
* @type: type of data
*
* Release a nft_data item. NFT_DATA_VALUE types can be silently discarded,
* all others need to be released by calling this function.
*/
void nft_data_uninit(const struct nft_data *data, enum nft_data_types type)
{
switch (type) {
case NFT_DATA_VALUE:
return;
case NFT_DATA_VERDICT:
return nft_verdict_uninit(data);
default:
WARN_ON(1);
}
}
EXPORT_SYMBOL_GPL(nft_data_uninit);
int nft_data_dump(struct sk_buff *skb, int attr, const struct nft_data *data,
enum nft_data_types type, unsigned int len)
{
struct nlattr *nest;
int err;
nest = nla_nest_start(skb, attr);
if (nest == NULL)
return -1;
switch (type) {
case NFT_DATA_VALUE:
err = nft_value_dump(skb, data, len);
break;
case NFT_DATA_VERDICT:
err = nft_verdict_dump(skb, data);
break;
default:
err = -EINVAL;
WARN_ON(1);
}
nla_nest_end(skb, nest);
return err;
}
EXPORT_SYMBOL_GPL(nft_data_dump);
static int nf_tables_init_net(struct net *net)
{
INIT_LIST_HEAD(&net->nft.af_info);
INIT_LIST_HEAD(&net->nft.commit_list);
return 0;
}
static struct pernet_operations nf_tables_net_ops = {
.init = nf_tables_init_net,
};
static int __init nf_tables_module_init(void)
{
int err;
info = kmalloc(sizeof(struct nft_expr_info) * NFT_RULE_MAXEXPRS,
GFP_KERNEL);
if (info == NULL) {
err = -ENOMEM;
goto err1;
}
err = nf_tables_core_module_init();
if (err < 0)
goto err2;
err = nfnetlink_subsys_register(&nf_tables_subsys);
if (err < 0)
goto err3;
pr_info("nf_tables: (c) 2007-2009 Patrick McHardy <kaber@trash.net>\n");
return register_pernet_subsys(&nf_tables_net_ops);
err3:
nf_tables_core_module_exit();
err2:
kfree(info);
err1:
return err;
}
static void __exit nf_tables_module_exit(void)
{
unregister_pernet_subsys(&nf_tables_net_ops);
nfnetlink_subsys_unregister(&nf_tables_subsys);
nf_tables_core_module_exit();
kfree(info);
}
module_init(nf_tables_module_init);
module_exit(nf_tables_module_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_NFTABLES);