Commit 9370761c authored by Pablo Neira Ayuso's avatar Pablo Neira Ayuso
Browse files

netfilter: nf_tables: convert built-in tables/chains to chain types



This patch converts built-in tables/chains to chain types that
allows you to deploy customized table and chain configurations from
userspace.

After this patch, you have to specify the chain type when
creating a new chain:

 add chain ip filter output { type filter hook input priority 0; }
                              ^^^^ ------

The existing chain types after this patch are: filter, route and
nat. Note that tables are just containers of chains with no specific
semantics, which is a significant change with regards to iptables.
Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
parent c29b72e0
......@@ -336,7 +336,6 @@ static inline struct nft_expr *nft_expr_last(const struct nft_rule *rule)
enum nft_chain_flags {
NFT_BASE_CHAIN = 0x1,
NFT_CHAIN_BUILTIN = 0x2,
};
/**
......@@ -362,14 +361,23 @@ struct nft_chain {
char name[NFT_CHAIN_MAXNAMELEN];
};
enum nft_chain_type {
NFT_CHAIN_T_DEFAULT = 0,
NFT_CHAIN_T_ROUTE,
NFT_CHAIN_T_NAT,
NFT_CHAIN_T_MAX
};
/**
* struct nft_base_chain - nf_tables base chain
*
* @ops: netfilter hook ops
* @type: chain type
* @chain: the chain
*/
struct nft_base_chain {
struct nf_hook_ops ops;
enum nft_chain_type type;
struct nft_chain chain;
};
......@@ -384,10 +392,6 @@ extern unsigned int nft_do_chain(const struct nf_hook_ops *ops,
const struct net_device *out,
int (*okfn)(struct sk_buff *));
enum nft_table_flags {
NFT_TABLE_BUILTIN = 0x1,
};
/**
* struct nft_table - nf_tables table
*
......@@ -431,8 +435,17 @@ struct nft_af_info {
extern int nft_register_afinfo(struct nft_af_info *);
extern void nft_unregister_afinfo(struct nft_af_info *);
extern int nft_register_table(struct nft_table *, int family);
extern void nft_unregister_table(struct nft_table *, int family);
struct nf_chain_type {
unsigned int hook_mask;
const char *name;
enum nft_chain_type type;
nf_hookfn *fn[NF_MAX_HOOKS];
struct module *me;
int family;
};
extern int nft_register_chain_type(struct nf_chain_type *);
extern void nft_unregister_chain_type(struct nf_chain_type *);
extern int nft_register_expr(struct nft_expr_type *);
extern void nft_unregister_expr(struct nft_expr_type *);
......@@ -440,8 +453,8 @@ extern void nft_unregister_expr(struct nft_expr_type *);
#define MODULE_ALIAS_NFT_FAMILY(family) \
MODULE_ALIAS("nft-afinfo-" __stringify(family))
#define MODULE_ALIAS_NFT_TABLE(family, name) \
MODULE_ALIAS("nft-table-" __stringify(family) "-" name)
#define MODULE_ALIAS_NFT_CHAIN(family, name) \
MODULE_ALIAS("nft-chain-" __stringify(family) "-" name)
#define MODULE_ALIAS_NFT_EXPR(name) \
MODULE_ALIAS("nft-expr-" name)
......
......@@ -115,6 +115,7 @@ enum nft_table_attributes {
* @NFTA_CHAIN_HANDLE: numeric handle of the chain (NLA_U64)
* @NFTA_CHAIN_NAME: name of the chain (NLA_STRING)
* @NFTA_CHAIN_HOOK: hook specification for basechains (NLA_NESTED: nft_hook_attributes)
* @NFTA_CHAIN_TYPE: type name of the string (NLA_NUL_STRING)
*/
enum nft_chain_attributes {
NFTA_CHAIN_UNSPEC,
......@@ -122,6 +123,7 @@ enum nft_chain_attributes {
NFTA_CHAIN_HANDLE,
NFTA_CHAIN_NAME,
NFTA_CHAIN_HOOK,
NFTA_CHAIN_TYPE,
__NFTA_CHAIN_MAX
};
#define NFTA_CHAIN_MAX (__NFTA_CHAIN_MAX - 1)
......
......@@ -44,13 +44,13 @@ config NFT_REJECT_IPV4
depends on NF_TABLES_IPV4
tristate "nf_tables IPv4 reject support"
config NF_TABLE_ROUTE_IPV4
config NFT_CHAIN_ROUTE_IPV4
depends on NF_TABLES_IPV4
tristate "IPv4 nf_tables route table support"
tristate "IPv4 nf_tables route chain support"
config NF_TABLE_NAT_IPV4
config NFT_CHAIN_NAT_IPV4
depends on NF_TABLES_IPV4
tristate "IPv4 nf_tables nat table support"
tristate "IPv4 nf_tables nat chain support"
config IP_NF_IPTABLES
tristate "IP tables support (required for filtering/masq/NAT)"
......
......@@ -29,8 +29,8 @@ obj-$(CONFIG_NF_NAT_PROTO_GRE) += nf_nat_proto_gre.o
obj-$(CONFIG_NF_TABLES_IPV4) += nf_tables_ipv4.o
obj-$(CONFIG_NFT_REJECT_IPV4) += nft_reject_ipv4.o
obj-$(CONFIG_NF_TABLE_ROUTE_IPV4) += nf_table_route_ipv4.o
obj-$(CONFIG_NF_TABLE_NAT_IPV4) += nf_table_nat_ipv4.o
obj-$(CONFIG_NFT_CHAIN_ROUTE_IPV4) += nft_chain_route_ipv4.o
obj-$(CONFIG_NFT_CHAIN_NAT_IPV4) += nft_chain_nat_ipv4.o
# generic IP tables
obj-$(CONFIG_IP_NF_IPTABLES) += ip_tables.o
......
/*
* Copyright (c) 2008 Patrick McHardy <kaber@trash.net>
* Copyright (c) 2012-2013 Pablo Neira Ayuso <pablo@netfilter.org>
*
* 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
......@@ -41,14 +42,34 @@ static struct nft_af_info nft_af_ipv4 __read_mostly = {
},
};
static struct nf_chain_type filter_ipv4 = {
.family = NFPROTO_IPV4,
.name = "filter",
.type = NFT_CHAIN_T_DEFAULT,
.hook_mask = (1 << NF_INET_LOCAL_IN) |
(1 << NF_INET_LOCAL_OUT) |
(1 << NF_INET_FORWARD) |
(1 << NF_INET_PRE_ROUTING) |
(1 << NF_INET_POST_ROUTING),
.fn = {
[NF_INET_LOCAL_IN] = nft_do_chain,
[NF_INET_LOCAL_OUT] = nft_do_chain,
[NF_INET_FORWARD] = nft_do_chain,
[NF_INET_PRE_ROUTING] = nft_do_chain,
[NF_INET_POST_ROUTING] = nft_do_chain,
},
};
static int __init nf_tables_ipv4_init(void)
{
nft_register_chain_type(&filter_ipv4);
return nft_register_afinfo(&nft_af_ipv4);
}
static void __exit nf_tables_ipv4_exit(void)
{
nft_unregister_afinfo(&nft_af_ipv4);
nft_unregister_chain_type(&filter_ipv4);
}
module_init(nf_tables_ipv4_init);
......
/*
* Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
* Copyright (c) 2012 Pablo Neira Ayuso <pablo@netfilter.org>
*
* 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
......@@ -167,7 +168,7 @@ static struct nft_expr_type nft_nat_type __read_mostly = {
};
/*
* NAT table
* NAT chains
*/
static unsigned int nf_nat_fn(const struct nf_hook_ops *ops,
......@@ -301,115 +302,52 @@ static unsigned int nf_nat_output(const struct nf_hook_ops *ops,
return ret;
}
static struct nft_base_chain nf_chain_nat_prerouting __read_mostly = {
.chain = {
.name = "PREROUTING",
.rules = LIST_HEAD_INIT(nf_chain_nat_prerouting.chain.rules),
.flags = NFT_BASE_CHAIN | NFT_CHAIN_BUILTIN,
},
.ops = {
.hook = nf_nat_prerouting,
.owner = THIS_MODULE,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_PRE_ROUTING,
.priority = NF_IP_PRI_NAT_DST,
.priv = &nf_chain_nat_prerouting.chain,
},
};
static struct nft_base_chain nf_chain_nat_postrouting __read_mostly = {
.chain = {
.name = "POSTROUTING",
.rules = LIST_HEAD_INIT(nf_chain_nat_postrouting.chain.rules),
.flags = NFT_BASE_CHAIN | NFT_CHAIN_BUILTIN,
},
.ops = {
.hook = nf_nat_postrouting,
.owner = THIS_MODULE,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_POST_ROUTING,
.priority = NF_IP_PRI_NAT_SRC,
.priv = &nf_chain_nat_postrouting.chain,
},
};
static struct nft_base_chain nf_chain_nat_output __read_mostly = {
.chain = {
.name = "OUTPUT",
.rules = LIST_HEAD_INIT(nf_chain_nat_output.chain.rules),
.flags = NFT_BASE_CHAIN | NFT_CHAIN_BUILTIN,
},
.ops = {
.hook = nf_nat_output,
.owner = THIS_MODULE,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_LOCAL_OUT,
.priority = NF_IP_PRI_NAT_DST,
.priv = &nf_chain_nat_output.chain,
},
};
static struct nft_base_chain nf_chain_nat_input __read_mostly = {
.chain = {
.name = "INPUT",
.rules = LIST_HEAD_INIT(nf_chain_nat_input.chain.rules),
.flags = NFT_BASE_CHAIN | NFT_CHAIN_BUILTIN,
},
.ops = {
.hook = nf_nat_fn,
.owner = THIS_MODULE,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_LOCAL_IN,
.priority = NF_IP_PRI_NAT_SRC,
.priv = &nf_chain_nat_input.chain,
struct nf_chain_type nft_chain_nat_ipv4 = {
.family = NFPROTO_IPV4,
.name = "nat",
.type = NFT_CHAIN_T_NAT,
.hook_mask = (1 << NF_INET_PRE_ROUTING) |
(1 << NF_INET_POST_ROUTING) |
(1 << NF_INET_LOCAL_OUT) |
(1 << NF_INET_LOCAL_IN),
.fn = {
[NF_INET_PRE_ROUTING] = nf_nat_prerouting,
[NF_INET_POST_ROUTING] = nf_nat_postrouting,
[NF_INET_LOCAL_OUT] = nf_nat_output,
[NF_INET_LOCAL_IN] = nf_nat_fn,
},
.me = THIS_MODULE,
};
static struct nft_table nf_table_nat_ipv4 __read_mostly = {
.name = "nat",
.chains = LIST_HEAD_INIT(nf_table_nat_ipv4.chains),
};
static int __init nf_table_nat_init(void)
static int __init nft_chain_nat_init(void)
{
int err;
list_add_tail(&nf_chain_nat_prerouting.chain.list,
&nf_table_nat_ipv4.chains);
list_add_tail(&nf_chain_nat_postrouting.chain.list,
&nf_table_nat_ipv4.chains);
list_add_tail(&nf_chain_nat_output.chain.list,
&nf_table_nat_ipv4.chains);
list_add_tail(&nf_chain_nat_input.chain.list,
&nf_table_nat_ipv4.chains);
err = nft_register_table(&nf_table_nat_ipv4, NFPROTO_IPV4);
err = nft_register_chain_type(&nft_chain_nat_ipv4);
if (err < 0)
goto err1;
return err;
err = nft_register_expr(&nft_nat_type);
if (err < 0)
goto err2;
goto err;
return 0;
err2:
nft_unregister_table(&nf_table_nat_ipv4, NFPROTO_IPV4);
err1:
err:
nft_unregister_chain_type(&nft_chain_nat_ipv4);
return err;
}
static void __exit nf_table_nat_exit(void)
static void __exit nft_chain_nat_exit(void)
{
nft_unregister_expr(&nft_nat_type);
nft_unregister_table(&nf_table_nat_ipv4, AF_INET);
nft_unregister_chain_type(&nft_chain_nat_ipv4);
}
module_init(nf_table_nat_init);
module_exit(nf_table_nat_exit);
module_init(nft_chain_nat_init);
module_exit(nft_chain_nat_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_ALIAS_NFT_TABLE(AF_INET, "nat");
MODULE_ALIAS_NFT_CHAIN(AF_INET, "nat");
MODULE_ALIAS_NFT_EXPR("nat");
/*
* Copyright (c) 2008 Patrick McHardy <kaber@trash.net>
* Copyright (c) 2012 Pablo Neira Ayuso <pablo@netfilter.org>
*
* 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
......@@ -56,42 +57,30 @@ static unsigned int nf_route_table_hook(const struct nf_hook_ops *ops,
return ret;
}
static struct nft_base_chain nf_chain_route_output __read_mostly = {
.chain = {
.name = "OUTPUT",
.rules = LIST_HEAD_INIT(nf_chain_route_output.chain.rules),
.flags = NFT_BASE_CHAIN | NFT_CHAIN_BUILTIN,
static struct nf_chain_type nft_chain_route_ipv4 = {
.family = NFPROTO_IPV4,
.name = "route",
.type = NFT_CHAIN_T_ROUTE,
.hook_mask = (1 << NF_INET_LOCAL_OUT),
.fn = {
[NF_INET_LOCAL_OUT] = nf_route_table_hook,
},
.ops = {
.hook = nf_route_table_hook,
.owner = THIS_MODULE,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_LOCAL_OUT,
.priority = NF_IP_PRI_MANGLE,
.priv = &nf_chain_route_output.chain,
},
};
static struct nft_table nf_table_route_ipv4 __read_mostly = {
.name = "route",
.chains = LIST_HEAD_INIT(nf_table_route_ipv4.chains),
.me = THIS_MODULE,
};
static int __init nf_table_route_init(void)
static int __init nft_chain_route_init(void)
{
list_add_tail(&nf_chain_route_output.chain.list,
&nf_table_route_ipv4.chains);
return nft_register_table(&nf_table_route_ipv4, NFPROTO_IPV4);
return nft_register_chain_type(&nft_chain_route_ipv4);
}
static void __exit nf_table_route_exit(void)
static void __exit nft_chain_route_exit(void)
{
nft_unregister_table(&nf_table_route_ipv4, NFPROTO_IPV4);
nft_unregister_chain_type(&nft_chain_route_ipv4);
}
module_init(nf_table_route_init);
module_exit(nf_table_route_exit);
module_init(nft_chain_route_init);
module_exit(nft_chain_route_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_ALIAS_NFT_TABLE(AF_INET, "route");
MODULE_ALIAS_NFT_CHAIN(AF_INET, "route");
......@@ -29,9 +29,9 @@ config NF_TABLES_IPV6
depends on NF_TABLES
tristate "IPv6 nf_tables support"
config NF_TABLE_ROUTE_IPV6
config NFT_CHAIN_ROUTE_IPV6
depends on NF_TABLES_IPV6
tristate "IPv6 nf_tables route table support"
tristate "IPv6 nf_tables route chain support"
config IP6_NF_IPTABLES
tristate "IP6 tables support (required for filtering)"
......
......@@ -25,7 +25,7 @@ obj-$(CONFIG_NF_DEFRAG_IPV6) += nf_defrag_ipv6.o
# nf_tables
obj-$(CONFIG_NF_TABLES_IPV6) += nf_tables_ipv6.o
obj-$(CONFIG_NF_TABLE_ROUTE_IPV6) += nf_table_route_ipv6.o
obj-$(CONFIG_NFT_CHAIN_ROUTE_IPV6) += nft_chain_route_ipv6.o
# matches
obj-$(CONFIG_IP6_NF_MATCH_AH) += ip6t_ah.o
......
/*
* Copyright (c) 2008 Patrick McHardy <kaber@trash.net>
* Copyright (c) 2012-2013 Pablo Neira Ayuso <pablo@netfilter.org>
*
* 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
......@@ -39,14 +40,33 @@ static struct nft_af_info nft_af_ipv6 __read_mostly = {
},
};
static struct nf_chain_type filter_ipv6 = {
.family = NFPROTO_IPV6,
.name = "filter",
.type = NFT_CHAIN_T_DEFAULT,
.hook_mask = (1 << NF_INET_LOCAL_IN) |
(1 << NF_INET_LOCAL_OUT) |
(1 << NF_INET_FORWARD) |
(1 << NF_INET_PRE_ROUTING) |
(1 << NF_INET_POST_ROUTING),
.fn = {
[NF_INET_LOCAL_IN] = nft_do_chain,
[NF_INET_LOCAL_OUT] = nft_do_chain,
[NF_INET_FORWARD] = nft_do_chain,
[NF_INET_PRE_ROUTING] = nft_do_chain,
[NF_INET_POST_ROUTING] = nft_do_chain,
},
};
static int __init nf_tables_ipv6_init(void)
{
nft_register_chain_type(&filter_ipv6);
return nft_register_afinfo(&nft_af_ipv6);
}
static void __exit nf_tables_ipv6_exit(void)
{
nft_unregister_afinfo(&nft_af_ipv6);
nft_unregister_chain_type(&filter_ipv6);
}
module_init(nf_tables_ipv6_init);
......
/*
* Copyright (c) 2008 Patrick McHardy <kaber@trash.net>
* Copyright (c) 2012 Pablo Neira Ayuso <pablo@netfilter.org>
*
* 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
......@@ -52,42 +53,30 @@ static unsigned int nf_route_table_hook(const struct nf_hook_ops *ops,
return ret;
}
static struct nft_base_chain nf_chain_route_output __read_mostly = {
.chain = {
.name = "OUTPUT",
.rules = LIST_HEAD_INIT(nf_chain_route_output.chain.rules),
.flags = NFT_BASE_CHAIN | NFT_CHAIN_BUILTIN,
},
.ops = {
.hook = nf_route_table_hook,
.owner = THIS_MODULE,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_LOCAL_OUT,
.priority = NF_IP6_PRI_MANGLE,
.priv = &nf_chain_route_output.chain,
},
static struct nf_chain_type nft_chain_route_ipv6 = {
.family = NFPROTO_IPV6,
.name = "route",
.type = NFT_CHAIN_T_ROUTE,
.hook_mask = (1 << NF_INET_LOCAL_OUT),
.fn = {
[NF_INET_LOCAL_OUT] = nf_route_table_hook,
},
.me = THIS_MODULE,
};
static struct nft_table nf_table_route_ipv6 __read_mostly = {
.name = "route",
.chains = LIST_HEAD_INIT(nf_table_route_ipv6.chains),
};
static int __init nf_table_route_init(void)
static int __init nft_chain_route_init(void)
{
list_add_tail(&nf_chain_route_output.chain.list,
&nf_table_route_ipv6.chains);
return nft_register_table(&nf_table_route_ipv6, NFPROTO_IPV6);
return nft_register_chain_type(&nft_chain_route_ipv6);
}
static void __exit nf_table_route_exit(void)
static void __exit nft_chain_route_exit(void)
{
nft_unregister_table(&nf_table_route_ipv6, NFPROTO_IPV6);
nft_unregister_chain_type(&nft_chain_route_ipv6);
}
module_init(nf_table_route_init);
module_exit(nf_table_route_exit);
module_init(nft_chain_route_init);
module_exit(nft_chain_route_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_ALIAS_NFT_TABLE(AF_INET6, "route");
MODULE_ALIAS_NFT_CHAIN(AF_INET6, "route");
......@@ -104,8 +104,7 @@ static struct nft_table *nft_table_lookup(const struct nft_af_info *afi,
}
static struct nft_table *nf_tables_table_lookup(const struct nft_af_info *afi,
const struct nlattr *nla,
bool autoload)
const struct nlattr *nla)
{
struct nft_table *table;
......@@ -116,16 +115,6 @@ static struct nft_table *nf_tables_table_lookup(const struct nft_af_info *afi,
if (table != NULL)
return table;
#ifdef CONFIG_MODULES
if (autoload) {
nfnl_unlock(NFNL_SUBSYS_NFTABLES);
request_module("nft-table-%u-%*.s", afi->family,
nla_len(nla)-1, (const char *)nla_data(nla));
nfnl_lock(NFNL_SUBSYS_NFTABLES);
if (nft_table_lookup(afi, nla))
return ERR_PTR(-EAGAIN);
}
#endif
return ERR_PTR(-ENOENT);
}
......@@ -134,6 +123,39 @@ static inline u64 nf_tables_alloc_handle(struct nft_table *table)
return ++table->hgenerator;
}
static struct nf_chain_type *chain_type[AF_MAX][NFT_CHAIN_T_MAX];
static int __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 i;
}
return -1;
}
static int nf_tables_chain_type_lookup(const struct nft_af_info *afi,
const struct nlattr *nla,
bool autoload)
{
int type;
type = __nf_tables_chain_type_lookup(afi->family, nla);
#ifdef CONFIG_MODULES
if (type < 0 && 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);
}
#endif
return type;
}
static const struct nla_policy nft_table_policy[NFTA_TABLE_MAX + 1] = {
[NFTA_TABLE_NAME] = { .type = NLA_STRING },
};
......@@ -258,7 +280,7 @@ static int nf_tables_gettable(struct sock *nlsk, struct sk_buff *skb,
if (IS_ERR(afi))
return PTR_ERR(afi);
table = nf_tables_table_lookup(afi, nla[NFTA_TABLE_NAME], false);
table = nf_tables_table_lookup(afi, nla[NFTA_TABLE_NAME]);
if (IS_ERR(table))
return PTR_ERR(table);
......@@ -294,7 +316,7 @@ static int nf_tables_newtable(struct sock *nlsk, struct sk_buff *skb,
return PTR_ERR(afi);
name = nla[NFTA_TABLE_NAME];
table = nf_tables_table_lookup(afi, name, false);
table = nf_tables_table_lookup(afi, name);
if (IS_ERR(table)) {
if (PTR_ERR(table) != -ENOENT)
return PTR_ERR(table);
......@@ -335,13 +357,10 @@ static int nf_tables_deltable(struct sock *nlsk, struct sk_buff *skb,
if (IS_ERR(afi))
return PTR_ERR(afi);
table = nf_tables_table_lookup(afi, nla[NFTA_TABLE_NAME], false);
table = nf_tables_table_lookup(afi, nla[NFTA_TABLE_NAME]);
if (IS_ERR(table))
return PTR_ERR(table);
if (table->flags & NFT_TABLE_BUILTIN)
return -EOPNOTSUPP;
if (table->use)
return -EBUSY;