netfilter: xtables: generate initial table on-demand

The static initial tables are pretty large, and after the net
namespace has been instantiated, they just hang around for nothing.
This commit removes them and creates tables on-demand at runtime when
needed.

Size shrinks by 7735 bytes (x86_64).

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
This commit is contained in:
Jan Engelhardt 2009-06-17 22:14:54 +02:00
parent 2b95efe7f6
commit e3eaa9910b
18 changed files with 141 additions and 334 deletions

View File

@ -258,6 +258,7 @@ struct arpt_error {
.target.errorname = "ERROR", \
}
extern void *arpt_alloc_initial_table(const struct xt_table *);
extern struct xt_table *arpt_register_table(struct net *net,
const struct xt_table *table,
const struct arpt_replace *repl);

View File

@ -282,6 +282,7 @@ struct ipt_error {
.target.errorname = "ERROR", \
}
extern void *ipt_alloc_initial_table(const struct xt_table *);
extern unsigned int ipt_do_table(struct sk_buff *skb,
unsigned int hook,
const struct net_device *in,

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@ -297,6 +297,7 @@ ip6t_get_target(struct ip6t_entry *e)
#include <linux/init.h>
extern void ip6t_init(void) __init;
extern void *ip6t_alloc_initial_table(const struct xt_table *);
extern struct xt_table *ip6t_register_table(struct net *net,
const struct xt_table *table,
const struct ip6t_replace *repl);

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@ -27,6 +27,7 @@
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_arp/arp_tables.h>
#include "../../netfilter/xt_repldata.h"
MODULE_LICENSE("GPL");
MODULE_AUTHOR("David S. Miller <davem@redhat.com>");
@ -58,6 +59,12 @@ do { \
#define ARP_NF_ASSERT(x)
#endif
void *arpt_alloc_initial_table(const struct xt_table *info)
{
return xt_alloc_initial_table(arpt, ARPT);
}
EXPORT_SYMBOL_GPL(arpt_alloc_initial_table);
static inline int arp_devaddr_compare(const struct arpt_devaddr_info *ap,
const char *hdr_addr, int len)
{

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@ -6,6 +6,7 @@
*/
#include <linux/module.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_arp/arp_tables.h>
MODULE_LICENSE("GPL");
@ -15,36 +16,6 @@ MODULE_DESCRIPTION("arptables filter table");
#define FILTER_VALID_HOOKS ((1 << NF_ARP_IN) | (1 << NF_ARP_OUT) | \
(1 << NF_ARP_FORWARD))
static const struct
{
struct arpt_replace repl;
struct arpt_standard entries[3];
struct arpt_error term;
} initial_table __net_initdata = {
.repl = {
.name = "filter",
.valid_hooks = FILTER_VALID_HOOKS,
.num_entries = 4,
.size = sizeof(struct arpt_standard) * 3 + sizeof(struct arpt_error),
.hook_entry = {
[NF_ARP_IN] = 0,
[NF_ARP_OUT] = sizeof(struct arpt_standard),
[NF_ARP_FORWARD] = 2 * sizeof(struct arpt_standard),
},
.underflow = {
[NF_ARP_IN] = 0,
[NF_ARP_OUT] = sizeof(struct arpt_standard),
[NF_ARP_FORWARD] = 2 * sizeof(struct arpt_standard),
},
},
.entries = {
ARPT_STANDARD_INIT(NF_ACCEPT), /* ARP_IN */
ARPT_STANDARD_INIT(NF_ACCEPT), /* ARP_OUT */
ARPT_STANDARD_INIT(NF_ACCEPT), /* ARP_FORWARD */
},
.term = ARPT_ERROR_INIT,
};
static const struct xt_table packet_filter = {
.name = "filter",
.valid_hooks = FILTER_VALID_HOOKS,
@ -68,9 +39,14 @@ static struct nf_hook_ops *arpfilter_ops __read_mostly;
static int __net_init arptable_filter_net_init(struct net *net)
{
/* Register table */
struct arpt_replace *repl;
repl = arpt_alloc_initial_table(&packet_filter);
if (repl == NULL)
return -ENOMEM;
net->ipv4.arptable_filter =
arpt_register_table(net, &packet_filter, &initial_table.repl);
arpt_register_table(net, &packet_filter, repl);
kfree(repl);
if (IS_ERR(net->ipv4.arptable_filter))
return PTR_ERR(net->ipv4.arptable_filter);
return 0;

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@ -28,6 +28,7 @@
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_ipv4/ip_tables.h>
#include <net/netfilter/nf_log.h>
#include "../../netfilter/xt_repldata.h"
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
@ -66,6 +67,12 @@ do { \
#define inline
#endif
void *ipt_alloc_initial_table(const struct xt_table *info)
{
return xt_alloc_initial_table(ipt, IPT);
}
EXPORT_SYMBOL_GPL(ipt_alloc_initial_table);
/*
We keep a set of rules for each CPU, so we can avoid write-locking
them in the softirq when updating the counters and therefore

View File

@ -23,36 +23,6 @@ MODULE_DESCRIPTION("iptables filter table");
(1 << NF_INET_FORWARD) | \
(1 << NF_INET_LOCAL_OUT))
static struct
{
struct ipt_replace repl;
struct ipt_standard entries[3];
struct ipt_error term;
} initial_table __net_initdata = {
.repl = {
.name = "filter",
.valid_hooks = FILTER_VALID_HOOKS,
.num_entries = 4,
.size = sizeof(struct ipt_standard) * 3 + sizeof(struct ipt_error),
.hook_entry = {
[NF_INET_LOCAL_IN] = 0,
[NF_INET_FORWARD] = sizeof(struct ipt_standard),
[NF_INET_LOCAL_OUT] = sizeof(struct ipt_standard) * 2,
},
.underflow = {
[NF_INET_LOCAL_IN] = 0,
[NF_INET_FORWARD] = sizeof(struct ipt_standard),
[NF_INET_LOCAL_OUT] = sizeof(struct ipt_standard) * 2,
},
},
.entries = {
IPT_STANDARD_INIT(NF_ACCEPT), /* LOCAL_IN */
IPT_STANDARD_INIT(NF_ACCEPT), /* FORWARD */
IPT_STANDARD_INIT(NF_ACCEPT), /* LOCAL_OUT */
},
.term = IPT_ERROR_INIT, /* ERROR */
};
static const struct xt_table packet_filter = {
.name = "filter",
.valid_hooks = FILTER_VALID_HOOKS,
@ -86,9 +56,18 @@ module_param(forward, bool, 0000);
static int __net_init iptable_filter_net_init(struct net *net)
{
/* Register table */
struct ipt_replace *repl;
repl = ipt_alloc_initial_table(&packet_filter);
if (repl == NULL)
return -ENOMEM;
/* Entry 1 is the FORWARD hook */
((struct ipt_standard *)repl->entries)[1].target.verdict =
-forward - 1;
net->ipv4.iptable_filter =
ipt_register_table(net, &packet_filter, &initial_table.repl);
ipt_register_table(net, &packet_filter, repl);
kfree(repl);
if (IS_ERR(net->ipv4.iptable_filter))
return PTR_ERR(net->ipv4.iptable_filter);
return 0;
@ -113,9 +92,6 @@ static int __init iptable_filter_init(void)
return -EINVAL;
}
/* Entry 1 is the FORWARD hook */
initial_table.entries[1].target.verdict = -forward - 1;
ret = register_pernet_subsys(&iptable_filter_net_ops);
if (ret < 0)
return ret;

View File

@ -27,43 +27,6 @@ MODULE_DESCRIPTION("iptables mangle table");
(1 << NF_INET_LOCAL_OUT) | \
(1 << NF_INET_POST_ROUTING))
/* Ouch - five different hooks? Maybe this should be a config option..... -- BC */
static const struct
{
struct ipt_replace repl;
struct ipt_standard entries[5];
struct ipt_error term;
} initial_table __net_initdata = {
.repl = {
.name = "mangle",
.valid_hooks = MANGLE_VALID_HOOKS,
.num_entries = 6,
.size = sizeof(struct ipt_standard) * 5 + sizeof(struct ipt_error),
.hook_entry = {
[NF_INET_PRE_ROUTING] = 0,
[NF_INET_LOCAL_IN] = sizeof(struct ipt_standard),
[NF_INET_FORWARD] = sizeof(struct ipt_standard) * 2,
[NF_INET_LOCAL_OUT] = sizeof(struct ipt_standard) * 3,
[NF_INET_POST_ROUTING] = sizeof(struct ipt_standard) * 4,
},
.underflow = {
[NF_INET_PRE_ROUTING] = 0,
[NF_INET_LOCAL_IN] = sizeof(struct ipt_standard),
[NF_INET_FORWARD] = sizeof(struct ipt_standard) * 2,
[NF_INET_LOCAL_OUT] = sizeof(struct ipt_standard) * 3,
[NF_INET_POST_ROUTING] = sizeof(struct ipt_standard) * 4,
},
},
.entries = {
IPT_STANDARD_INIT(NF_ACCEPT), /* PRE_ROUTING */
IPT_STANDARD_INIT(NF_ACCEPT), /* LOCAL_IN */
IPT_STANDARD_INIT(NF_ACCEPT), /* FORWARD */
IPT_STANDARD_INIT(NF_ACCEPT), /* LOCAL_OUT */
IPT_STANDARD_INIT(NF_ACCEPT), /* POST_ROUTING */
},
.term = IPT_ERROR_INIT, /* ERROR */
};
static const struct xt_table packet_mangler = {
.name = "mangle",
.valid_hooks = MANGLE_VALID_HOOKS,
@ -134,9 +97,14 @@ static struct nf_hook_ops *mangle_ops __read_mostly;
static int __net_init iptable_mangle_net_init(struct net *net)
{
/* Register table */
struct ipt_replace *repl;
repl = ipt_alloc_initial_table(&packet_mangler);
if (repl == NULL)
return -ENOMEM;
net->ipv4.iptable_mangle =
ipt_register_table(net, &packet_mangler, &initial_table.repl);
ipt_register_table(net, &packet_mangler, repl);
kfree(repl);
if (IS_ERR(net->ipv4.iptable_mangle))
return PTR_ERR(net->ipv4.iptable_mangle);
return 0;

View File

@ -9,33 +9,6 @@
#define RAW_VALID_HOOKS ((1 << NF_INET_PRE_ROUTING) | (1 << NF_INET_LOCAL_OUT))
static const struct
{
struct ipt_replace repl;
struct ipt_standard entries[2];
struct ipt_error term;
} initial_table __net_initdata = {
.repl = {
.name = "raw",
.valid_hooks = RAW_VALID_HOOKS,
.num_entries = 3,
.size = sizeof(struct ipt_standard) * 2 + sizeof(struct ipt_error),
.hook_entry = {
[NF_INET_PRE_ROUTING] = 0,
[NF_INET_LOCAL_OUT] = sizeof(struct ipt_standard)
},
.underflow = {
[NF_INET_PRE_ROUTING] = 0,
[NF_INET_LOCAL_OUT] = sizeof(struct ipt_standard)
},
},
.entries = {
IPT_STANDARD_INIT(NF_ACCEPT), /* PRE_ROUTING */
IPT_STANDARD_INIT(NF_ACCEPT), /* LOCAL_OUT */
},
.term = IPT_ERROR_INIT, /* ERROR */
};
static const struct xt_table packet_raw = {
.name = "raw",
.valid_hooks = RAW_VALID_HOOKS,
@ -66,9 +39,14 @@ static struct nf_hook_ops *rawtable_ops __read_mostly;
static int __net_init iptable_raw_net_init(struct net *net)
{
/* Register table */
struct ipt_replace *repl;
repl = ipt_alloc_initial_table(&packet_raw);
if (repl == NULL)
return -ENOMEM;
net->ipv4.iptable_raw =
ipt_register_table(net, &packet_raw, &initial_table.repl);
ipt_register_table(net, &packet_raw, repl);
kfree(repl);
if (IS_ERR(net->ipv4.iptable_raw))
return PTR_ERR(net->ipv4.iptable_raw);
return 0;

View File

@ -27,36 +27,6 @@ MODULE_DESCRIPTION("iptables security table, for MAC rules");
(1 << NF_INET_FORWARD) | \
(1 << NF_INET_LOCAL_OUT)
static const struct
{
struct ipt_replace repl;
struct ipt_standard entries[3];
struct ipt_error term;
} initial_table __net_initdata = {
.repl = {
.name = "security",
.valid_hooks = SECURITY_VALID_HOOKS,
.num_entries = 4,
.size = sizeof(struct ipt_standard) * 3 + sizeof(struct ipt_error),
.hook_entry = {
[NF_INET_LOCAL_IN] = 0,
[NF_INET_FORWARD] = sizeof(struct ipt_standard),
[NF_INET_LOCAL_OUT] = sizeof(struct ipt_standard) * 2,
},
.underflow = {
[NF_INET_LOCAL_IN] = 0,
[NF_INET_FORWARD] = sizeof(struct ipt_standard),
[NF_INET_LOCAL_OUT] = sizeof(struct ipt_standard) * 2,
},
},
.entries = {
IPT_STANDARD_INIT(NF_ACCEPT), /* LOCAL_IN */
IPT_STANDARD_INIT(NF_ACCEPT), /* FORWARD */
IPT_STANDARD_INIT(NF_ACCEPT), /* LOCAL_OUT */
},
.term = IPT_ERROR_INIT, /* ERROR */
};
static const struct xt_table security_table = {
.name = "security",
.valid_hooks = SECURITY_VALID_HOOKS,
@ -87,9 +57,14 @@ static struct nf_hook_ops *sectbl_ops __read_mostly;
static int __net_init iptable_security_net_init(struct net *net)
{
net->ipv4.iptable_security =
ipt_register_table(net, &security_table, &initial_table.repl);
struct ipt_replace *repl;
repl = ipt_alloc_initial_table(&security_table);
if (repl == NULL)
return -ENOMEM;
net->ipv4.iptable_security =
ipt_register_table(net, &security_table, repl);
kfree(repl);
if (IS_ERR(net->ipv4.iptable_security))
return PTR_ERR(net->ipv4.iptable_security);

View File

@ -28,36 +28,6 @@
(1 << NF_INET_POST_ROUTING) | \
(1 << NF_INET_LOCAL_OUT))
static const struct
{
struct ipt_replace repl;
struct ipt_standard entries[3];
struct ipt_error term;
} nat_initial_table __net_initdata = {
.repl = {
.name = "nat",
.valid_hooks = NAT_VALID_HOOKS,
.num_entries = 4,
.size = sizeof(struct ipt_standard) * 3 + sizeof(struct ipt_error),
.hook_entry = {
[NF_INET_PRE_ROUTING] = 0,
[NF_INET_POST_ROUTING] = sizeof(struct ipt_standard),
[NF_INET_LOCAL_OUT] = sizeof(struct ipt_standard) * 2
},
.underflow = {
[NF_INET_PRE_ROUTING] = 0,
[NF_INET_POST_ROUTING] = sizeof(struct ipt_standard),
[NF_INET_LOCAL_OUT] = sizeof(struct ipt_standard) * 2
},
},
.entries = {
IPT_STANDARD_INIT(NF_ACCEPT), /* PRE_ROUTING */
IPT_STANDARD_INIT(NF_ACCEPT), /* POST_ROUTING */
IPT_STANDARD_INIT(NF_ACCEPT), /* LOCAL_OUT */
},
.term = IPT_ERROR_INIT, /* ERROR */
};
static const struct xt_table nat_table = {
.name = "nat",
.valid_hooks = NAT_VALID_HOOKS,
@ -186,8 +156,13 @@ static struct xt_target ipt_dnat_reg __read_mostly = {
static int __net_init nf_nat_rule_net_init(struct net *net)
{
net->ipv4.nat_table = ipt_register_table(net, &nat_table,
&nat_initial_table.repl);
struct ipt_replace *repl;
repl = ipt_alloc_initial_table(&nat_table);
if (repl == NULL)
return -ENOMEM;
net->ipv4.nat_table = ipt_register_table(net, &nat_table, repl);
kfree(repl);
if (IS_ERR(net->ipv4.nat_table))
return PTR_ERR(net->ipv4.nat_table);
return 0;

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@ -29,6 +29,7 @@
#include <linux/netfilter_ipv6/ip6_tables.h>
#include <linux/netfilter/x_tables.h>
#include <net/netfilter/nf_log.h>
#include "../../netfilter/xt_repldata.h"
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
@ -67,6 +68,12 @@ do { \
#define inline
#endif
void *ip6t_alloc_initial_table(const struct xt_table *info)
{
return xt_alloc_initial_table(ip6t, IP6T);
}
EXPORT_SYMBOL_GPL(ip6t_alloc_initial_table);
/*
We keep a set of rules for each CPU, so we can avoid write-locking
them in the softirq when updating the counters and therefore

View File

@ -21,36 +21,6 @@ MODULE_DESCRIPTION("ip6tables filter table");
(1 << NF_INET_FORWARD) | \
(1 << NF_INET_LOCAL_OUT))
static struct
{
struct ip6t_replace repl;
struct ip6t_standard entries[3];
struct ip6t_error term;
} initial_table __net_initdata = {
.repl = {
.name = "filter",
.valid_hooks = FILTER_VALID_HOOKS,
.num_entries = 4,
.size = sizeof(struct ip6t_standard) * 3 + sizeof(struct ip6t_error),
.hook_entry = {
[NF_INET_LOCAL_IN] = 0,
[NF_INET_FORWARD] = sizeof(struct ip6t_standard),
[NF_INET_LOCAL_OUT] = sizeof(struct ip6t_standard) * 2
},
.underflow = {
[NF_INET_LOCAL_IN] = 0,
[NF_INET_FORWARD] = sizeof(struct ip6t_standard),
[NF_INET_LOCAL_OUT] = sizeof(struct ip6t_standard) * 2
},
},
.entries = {
IP6T_STANDARD_INIT(NF_ACCEPT), /* LOCAL_IN */
IP6T_STANDARD_INIT(NF_ACCEPT), /* FORWARD */
IP6T_STANDARD_INIT(NF_ACCEPT), /* LOCAL_OUT */
},
.term = IP6T_ERROR_INIT, /* ERROR */
};
static const struct xt_table packet_filter = {
.name = "filter",
.valid_hooks = FILTER_VALID_HOOKS,
@ -78,9 +48,18 @@ module_param(forward, bool, 0000);
static int __net_init ip6table_filter_net_init(struct net *net)
{
/* Register table */
struct ip6t_replace *repl;
repl = ip6t_alloc_initial_table(&packet_filter);
if (repl == NULL)
return -ENOMEM;
/* Entry 1 is the FORWARD hook */
((struct ip6t_standard *)repl->entries)[1].target.verdict =
-forward - 1;
net->ipv6.ip6table_filter =
ip6t_register_table(net, &packet_filter, &initial_table.repl);
ip6t_register_table(net, &packet_filter, repl);
kfree(repl);
if (IS_ERR(net->ipv6.ip6table_filter))
return PTR_ERR(net->ipv6.ip6table_filter);
return 0;
@ -105,9 +84,6 @@ static int __init ip6table_filter_init(void)
return -EINVAL;
}
/* Entry 1 is the FORWARD hook */
initial_table.entries[1].target.verdict = -forward - 1;
ret = register_pernet_subsys(&ip6table_filter_net_ops);
if (ret < 0)
return ret;

View File

@ -21,42 +21,6 @@ MODULE_DESCRIPTION("ip6tables mangle table");
(1 << NF_INET_LOCAL_OUT) | \
(1 << NF_INET_POST_ROUTING))
static const struct
{
struct ip6t_replace repl;
struct ip6t_standard entries[5];
struct ip6t_error term;
} initial_table __net_initdata = {
.repl = {
.name = "mangle",
.valid_hooks = MANGLE_VALID_HOOKS,
.num_entries = 6,
.size = sizeof(struct ip6t_standard) * 5 + sizeof(struct ip6t_error),
.hook_entry = {
[NF_INET_PRE_ROUTING] = 0,
[NF_INET_LOCAL_IN] = sizeof(struct ip6t_standard),
[NF_INET_FORWARD] = sizeof(struct ip6t_standard) * 2,
[NF_INET_LOCAL_OUT] = sizeof(struct ip6t_standard) * 3,
[NF_INET_POST_ROUTING] = sizeof(struct ip6t_standard) * 4,
},
.underflow = {
[NF_INET_PRE_ROUTING] = 0,
[NF_INET_LOCAL_IN] = sizeof(struct ip6t_standard),
[NF_INET_FORWARD] = sizeof(struct ip6t_standard) * 2,
[NF_INET_LOCAL_OUT] = sizeof(struct ip6t_standard) * 3,
[NF_INET_POST_ROUTING] = sizeof(struct ip6t_standard) * 4,
},
},
.entries = {
IP6T_STANDARD_INIT(NF_ACCEPT), /* PRE_ROUTING */
IP6T_STANDARD_INIT(NF_ACCEPT), /* LOCAL_IN */
IP6T_STANDARD_INIT(NF_ACCEPT), /* FORWARD */
IP6T_STANDARD_INIT(NF_ACCEPT), /* LOCAL_OUT */
IP6T_STANDARD_INIT(NF_ACCEPT), /* POST_ROUTING */
},
.term = IP6T_ERROR_INIT, /* ERROR */
};
static const struct xt_table packet_mangler = {
.name = "mangle",
.valid_hooks = MANGLE_VALID_HOOKS,
@ -126,9 +90,14 @@ ip6table_mangle_hook(unsigned int hook, struct sk_buff *skb,
static struct nf_hook_ops *mangle_ops __read_mostly;
static int __net_init ip6table_mangle_net_init(struct net *net)
{
/* Register table */
struct ip6t_replace *repl;
repl = ip6t_alloc_initial_table(&packet_mangler);
if (repl == NULL)
return -ENOMEM;
net->ipv6.ip6table_mangle =
ip6t_register_table(net, &packet_mangler, &initial_table.repl);
ip6t_register_table(net, &packet_mangler, repl);
kfree(repl);
if (IS_ERR(net->ipv6.ip6table_mangle))
return PTR_ERR(net->ipv6.ip6table_mangle);
return 0;

View File

@ -8,33 +8,6 @@
#define RAW_VALID_HOOKS ((1 << NF_INET_PRE_ROUTING) | (1 << NF_INET_LOCAL_OUT))
static const struct
{
struct ip6t_replace repl;
struct ip6t_standard entries[2];
struct ip6t_error term;
} initial_table __net_initdata = {
.repl = {
.name = "raw",
.valid_hooks = RAW_VALID_HOOKS,
.num_entries = 3,
.size = sizeof(struct ip6t_standard) * 2 + sizeof(struct ip6t_error),
.hook_entry = {
[NF_INET_PRE_ROUTING] = 0,
[NF_INET_LOCAL_OUT] = sizeof(struct ip6t_standard)
},
.underflow = {
[NF_INET_PRE_ROUTING] = 0,
[NF_INET_LOCAL_OUT] = sizeof(struct ip6t_standard)
},
},
.entries = {
IP6T_STANDARD_INIT(NF_ACCEPT), /* PRE_ROUTING */
IP6T_STANDARD_INIT(NF_ACCEPT), /* LOCAL_OUT */
},
.term = IP6T_ERROR_INIT, /* ERROR */
};
static const struct xt_table packet_raw = {
.name = "raw",
.valid_hooks = RAW_VALID_HOOKS,
@ -58,9 +31,14 @@ static struct nf_hook_ops *rawtable_ops __read_mostly;
static int __net_init ip6table_raw_net_init(struct net *net)
{
/* Register table */
struct ip6t_replace *repl;
repl = ip6t_alloc_initial_table(&packet_raw);
if (repl == NULL)
return -ENOMEM;
net->ipv6.ip6table_raw =
ip6t_register_table(net, &packet_raw, &initial_table.repl);
ip6t_register_table(net, &packet_raw, repl);
kfree(repl);
if (IS_ERR(net->ipv6.ip6table_raw))
return PTR_ERR(net->ipv6.ip6table_raw);
return 0;

View File

@ -26,36 +26,6 @@ MODULE_DESCRIPTION("ip6tables security table, for MAC rules");
(1 << NF_INET_FORWARD) | \
(1 << NF_INET_LOCAL_OUT)
static const struct
{
struct ip6t_replace repl;
struct ip6t_standard entries[3];
struct ip6t_error term;
} initial_table __net_initdata = {
.repl = {
.name = "security",
.valid_hooks = SECURITY_VALID_HOOKS,
.num_entries = 4,
.size = sizeof(struct ip6t_standard) * 3 + sizeof(struct ip6t_error),
.hook_entry = {
[NF_INET_LOCAL_IN] = 0,
[NF_INET_FORWARD] = sizeof(struct ip6t_standard),
[NF_INET_LOCAL_OUT] = sizeof(struct ip6t_standard) * 2,
},
.underflow = {
[NF_INET_LOCAL_IN] = 0,
[NF_INET_FORWARD] = sizeof(struct ip6t_standard),
[NF_INET_LOCAL_OUT] = sizeof(struct ip6t_standard) * 2,
},
},
.entries = {
IP6T_STANDARD_INIT(NF_ACCEPT), /* LOCAL_IN */
IP6T_STANDARD_INIT(NF_ACCEPT), /* FORWARD */
IP6T_STANDARD_INIT(NF_ACCEPT), /* LOCAL_OUT */
},
.term = IP6T_ERROR_INIT, /* ERROR */
};
static const struct xt_table security_table = {
.name = "security",
.valid_hooks = SECURITY_VALID_HOOKS,
@ -79,9 +49,14 @@ static struct nf_hook_ops *sectbl_ops __read_mostly;
static int __net_init ip6table_security_net_init(struct net *net)
{
net->ipv6.ip6table_security =
ip6t_register_table(net, &security_table, &initial_table.repl);
struct ip6t_replace *repl;
repl = ip6t_alloc_initial_table(&security_table);
if (repl == NULL)
return -ENOMEM;
net->ipv6.ip6table_security =
ip6t_register_table(net, &security_table, repl);
kfree(repl);
if (IS_ERR(net->ipv6.ip6table_security))
return PTR_ERR(net->ipv6.ip6table_security);

View File

@ -26,7 +26,9 @@
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_arp.h>
#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/netfilter_ipv6/ip6_tables.h>
#include <linux/netfilter_arp/arp_tables.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");

View File

@ -0,0 +1,35 @@
/*
* Today's hack: quantum tunneling in structs
*
* 'entries' and 'term' are never anywhere referenced by word in code. In fact,
* they serve as the hanging-off data accessed through repl.data[].
*/
#define xt_alloc_initial_table(type, typ2) ({ \
unsigned int hook_mask = info->valid_hooks; \
unsigned int nhooks = hweight32(hook_mask); \
unsigned int bytes = 0, hooknum = 0, i = 0; \
struct { \
struct type##_replace repl; \
struct type##_standard entries[nhooks]; \
struct type##_error term; \
} *tbl = kzalloc(sizeof(*tbl), GFP_KERNEL); \
if (tbl == NULL) \
return NULL; \
strncpy(tbl->repl.name, info->name, sizeof(tbl->repl.name)); \
tbl->term = (struct type##_error)typ2##_ERROR_INIT; \
tbl->repl.valid_hooks = hook_mask; \
tbl->repl.num_entries = nhooks + 1; \
tbl->repl.size = nhooks * sizeof(struct type##_standard) + \
sizeof(struct type##_error); \
for (; hook_mask != 0; hook_mask >>= 1, ++hooknum) { \
if (!(hook_mask & 1)) \
continue; \
tbl->repl.hook_entry[hooknum] = bytes; \
tbl->repl.underflow[hooknum] = bytes; \
tbl->entries[i++] = (struct type##_standard) \
typ2##_STANDARD_INIT(NF_ACCEPT); \
bytes += sizeof(struct type##_standard); \
} \
tbl; \
})