Commit ae689334 authored by Florian Westphal's avatar Florian Westphal Committed by Pablo Neira Ayuso

netfilter: ip_tables: pass table pointer via nf_hook_ops

iptable_x modules rely on 'struct net' to contain a pointer to the
table that should be evaluated.

In order to remove these pointers from struct net, pass them via
the 'priv' pointer in a similar fashion as nf_tables passes the
rule data.

To do that, duplicate the nf_hook_info array passed in from the
iptable_x modules, update the ops->priv pointers of the copy to
refer to the table and then change the hookfn implementations to
just pass the 'priv' argument to the traverser.

After this patch, the xt_table pointers can already be removed
from struct net.

However, changes to struct net result in re-compile of the entire
network stack, so do the removal after arptables and ip6tables
have been converted as well.
Signed-off-by: default avatarFlorian Westphal <fw@strlen.de>
Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
parent a4aeafa2
......@@ -229,6 +229,9 @@ struct xt_table {
/* Man behind the curtain... */
struct xt_table_info *private;
/* hook ops that register the table with the netfilter core */
struct nf_hook_ops *ops;
/* Set this to THIS_MODULE if you are a module, otherwise NULL */
struct module *me;
......
......@@ -24,11 +24,9 @@
int ipt_register_table(struct net *net, const struct xt_table *table,
const struct ipt_replace *repl,
const struct nf_hook_ops *ops, struct xt_table **res);
void ipt_unregister_table_pre_exit(struct net *net, const char *name,
const struct nf_hook_ops *ops);
void ipt_unregister_table_pre_exit(struct net *net, const char *name);
void ipt_unregister_table_exit(struct net *net, const char *name);
/* Standard entry. */
......
......@@ -1716,9 +1716,11 @@ static void __ipt_unregister_table(struct net *net, struct xt_table *table)
int ipt_register_table(struct net *net, const struct xt_table *table,
const struct ipt_replace *repl,
const struct nf_hook_ops *ops, struct xt_table **res)
const struct nf_hook_ops *template_ops)
{
int ret;
struct nf_hook_ops *ops;
unsigned int num_ops;
int ret, i;
struct xt_table_info *newinfo;
struct xt_table_info bootstrap = {0};
void *loc_cpu_entry;
......@@ -1732,40 +1734,57 @@ int ipt_register_table(struct net *net, const struct xt_table *table,
memcpy(loc_cpu_entry, repl->entries, repl->size);
ret = translate_table(net, newinfo, loc_cpu_entry, repl);
if (ret != 0)
goto out_free;
if (ret != 0) {
xt_free_table_info(newinfo);
return ret;
}
new_table = xt_register_table(net, table, &bootstrap, newinfo);
if (IS_ERR(new_table)) {
ret = PTR_ERR(new_table);
goto out_free;
xt_free_table_info(newinfo);
return PTR_ERR(new_table);
}
/* set res now, will see skbs right after nf_register_net_hooks */
WRITE_ONCE(*res, new_table);
if (!ops)
/* No template? No need to do anything. This is used by 'nat' table, it registers
* with the nat core instead of the netfilter core.
*/
if (!template_ops)
return 0;
ret = nf_register_net_hooks(net, ops, hweight32(table->valid_hooks));
if (ret != 0) {
__ipt_unregister_table(net, new_table);
*res = NULL;
num_ops = hweight32(table->valid_hooks);
if (num_ops == 0) {
ret = -EINVAL;
goto out_free;
}
ops = kmemdup(template_ops, sizeof(*ops) * num_ops, GFP_KERNEL);
if (!ops) {
ret = -ENOMEM;
goto out_free;
}
for (i = 0; i < num_ops; i++)
ops[i].priv = new_table;
new_table->ops = ops;
ret = nf_register_net_hooks(net, ops, num_ops);
if (ret != 0)
goto out_free;
return ret;
out_free:
xt_free_table_info(newinfo);
__ipt_unregister_table(net, new_table);
return ret;
}
void ipt_unregister_table_pre_exit(struct net *net, const char *name,
const struct nf_hook_ops *ops)
void ipt_unregister_table_pre_exit(struct net *net, const char *name)
{
struct xt_table *table = xt_find_table(net, NFPROTO_IPV4, name);
if (table)
nf_unregister_net_hooks(net, ops, hweight32(table->valid_hooks));
nf_unregister_net_hooks(net, table->ops, hweight32(table->valid_hooks));
}
void ipt_unregister_table_exit(struct net *net, const char *name)
......
......@@ -34,7 +34,7 @@ static unsigned int
iptable_filter_hook(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
return ipt_do_table(skb, state, state->net->ipv4.iptable_filter);
return ipt_do_table(skb, state, priv);
}
static struct nf_hook_ops *filter_ops __read_mostly;
......@@ -55,8 +55,7 @@ static int __net_init iptable_filter_table_init(struct net *net)
((struct ipt_standard *)repl->entries)[1].target.verdict =
forward ? -NF_ACCEPT - 1 : -NF_DROP - 1;
err = ipt_register_table(net, &packet_filter, repl, filter_ops,
&net->ipv4.iptable_filter);
err = ipt_register_table(net, &packet_filter, repl, filter_ops);
kfree(repl);
return err;
}
......@@ -71,13 +70,12 @@ static int __net_init iptable_filter_net_init(struct net *net)
static void __net_exit iptable_filter_net_pre_exit(struct net *net)
{
ipt_unregister_table_pre_exit(net, "filter", filter_ops);
ipt_unregister_table_pre_exit(net, "filter");
}
static void __net_exit iptable_filter_net_exit(struct net *net)
{
ipt_unregister_table_exit(net, "filter");
net->ipv4.iptable_filter = NULL;
}
static struct pernet_operations iptable_filter_net_ops = {
......
......@@ -37,7 +37,7 @@ static const struct xt_table packet_mangler = {
};
static unsigned int
ipt_mangle_out(struct sk_buff *skb, const struct nf_hook_state *state)
ipt_mangle_out(struct sk_buff *skb, const struct nf_hook_state *state, void *priv)
{
unsigned int ret;
const struct iphdr *iph;
......@@ -53,7 +53,7 @@ ipt_mangle_out(struct sk_buff *skb, const struct nf_hook_state *state)
daddr = iph->daddr;
tos = iph->tos;
ret = ipt_do_table(skb, state, state->net->ipv4.iptable_mangle);
ret = ipt_do_table(skb, state, priv);
/* Reroute for ANY change. */
if (ret != NF_DROP && ret != NF_STOLEN) {
iph = ip_hdr(skb);
......@@ -78,8 +78,8 @@ iptable_mangle_hook(void *priv,
const struct nf_hook_state *state)
{
if (state->hook == NF_INET_LOCAL_OUT)
return ipt_mangle_out(skb, state);
return ipt_do_table(skb, state, state->net->ipv4.iptable_mangle);
return ipt_mangle_out(skb, state, priv);
return ipt_do_table(skb, state, priv);
}
static struct nf_hook_ops *mangle_ops __read_mostly;
......@@ -91,21 +91,19 @@ static int __net_init iptable_mangle_table_init(struct net *net)
repl = ipt_alloc_initial_table(&packet_mangler);
if (repl == NULL)
return -ENOMEM;
ret = ipt_register_table(net, &packet_mangler, repl, mangle_ops,
&net->ipv4.iptable_mangle);
ret = ipt_register_table(net, &packet_mangler, repl, mangle_ops);
kfree(repl);
return ret;
}
static void __net_exit iptable_mangle_net_pre_exit(struct net *net)
{
ipt_unregister_table_pre_exit(net, "mangle", mangle_ops);
ipt_unregister_table_pre_exit(net, "mangle");
}
static void __net_exit iptable_mangle_net_exit(struct net *net)
{
ipt_unregister_table_exit(net, "mangle");
net->ipv4.iptable_mangle = NULL;
}
static struct pernet_operations iptable_mangle_net_ops = {
......
......@@ -66,12 +66,19 @@ static const struct nf_hook_ops nf_nat_ipv4_ops[] = {
},
};
static int ipt_nat_register_lookups(struct net *net, struct xt_table *table)
static int ipt_nat_register_lookups(struct net *net)
{
struct nf_hook_ops *ops = kmemdup(nf_nat_ipv4_ops, sizeof(nf_nat_ipv4_ops), GFP_KERNEL);
struct iptable_nat_pernet *xt_nat_net = net_generic(net, iptable_nat_net_id);
struct iptable_nat_pernet *xt_nat_net;
struct nf_hook_ops *ops;
struct xt_table *table;
int i, ret;
xt_nat_net = net_generic(net, iptable_nat_net_id);
table = xt_find_table(net, NFPROTO_IPV4, "nat");
if (WARN_ON_ONCE(!table))
return -ENOENT;
ops = kmemdup(nf_nat_ipv4_ops, sizeof(nf_nat_ipv4_ops), GFP_KERNEL);
if (!ops)
return -ENOMEM;
......@@ -109,25 +116,21 @@ static void ipt_nat_unregister_lookups(struct net *net)
static int __net_init iptable_nat_table_init(struct net *net)
{
struct ipt_replace *repl;
struct xt_table *table;
int ret;
repl = ipt_alloc_initial_table(&nf_nat_ipv4_table);
if (repl == NULL)
return -ENOMEM;
ret = ipt_register_table(net, &nf_nat_ipv4_table, repl,
NULL, &table);
ret = ipt_register_table(net, &nf_nat_ipv4_table, repl, NULL);
if (ret < 0) {
kfree(repl);
return ret;
}
ret = ipt_nat_register_lookups(net, table);
if (ret < 0) {
ret = ipt_nat_register_lookups(net);
if (ret < 0)
ipt_unregister_table_exit(net, "nat");
} else {
net->ipv4.nat_table = table;
}
kfree(repl);
return ret;
......@@ -141,7 +144,6 @@ static void __net_exit iptable_nat_net_pre_exit(struct net *net)
static void __net_exit iptable_nat_net_exit(struct net *net)
{
ipt_unregister_table_exit(net, "nat");
net->ipv4.nat_table = NULL;
}
static struct pernet_operations iptable_nat_net_ops = {
......
......@@ -41,7 +41,7 @@ static unsigned int
iptable_raw_hook(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
return ipt_do_table(skb, state, state->net->ipv4.iptable_raw);
return ipt_do_table(skb, state, priv);
}
static struct nf_hook_ops *rawtable_ops __read_mostly;
......@@ -58,21 +58,19 @@ static int __net_init iptable_raw_table_init(struct net *net)
repl = ipt_alloc_initial_table(table);
if (repl == NULL)
return -ENOMEM;
ret = ipt_register_table(net, table, repl, rawtable_ops,
&net->ipv4.iptable_raw);
ret = ipt_register_table(net, table, repl, rawtable_ops);
kfree(repl);
return ret;
}
static void __net_exit iptable_raw_net_pre_exit(struct net *net)
{
ipt_unregister_table_pre_exit(net, "raw", rawtable_ops);
ipt_unregister_table_pre_exit(net, "raw");
}
static void __net_exit iptable_raw_net_exit(struct net *net)
{
ipt_unregister_table_exit(net, "raw");
net->ipv4.iptable_raw = NULL;
}
static struct pernet_operations iptable_raw_net_ops = {
......
......@@ -40,7 +40,7 @@ static unsigned int
iptable_security_hook(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
return ipt_do_table(skb, state, state->net->ipv4.iptable_security);
return ipt_do_table(skb, state, priv);
}
static struct nf_hook_ops *sectbl_ops __read_mostly;
......@@ -53,21 +53,19 @@ static int __net_init iptable_security_table_init(struct net *net)
repl = ipt_alloc_initial_table(&security_table);
if (repl == NULL)
return -ENOMEM;
ret = ipt_register_table(net, &security_table, repl, sectbl_ops,
&net->ipv4.iptable_security);
ret = ipt_register_table(net, &security_table, repl, sectbl_ops);
kfree(repl);
return ret;
}
static void __net_exit iptable_security_net_pre_exit(struct net *net)
{
ipt_unregister_table_pre_exit(net, "security", sectbl_ops);
ipt_unregister_table_pre_exit(net, "security");
}
static void __net_exit iptable_security_net_exit(struct net *net)
{
ipt_unregister_table_exit(net, "security");
net->ipv4.iptable_security = NULL;
}
static struct pernet_operations iptable_security_net_ops = {
......
......@@ -1498,6 +1498,7 @@ void *xt_unregister_table(struct xt_table *table)
mutex_unlock(&xt[table->af].mutex);
audit_log_nfcfg(table->name, table->af, private->number,
AUDIT_XT_OP_UNREGISTER, GFP_KERNEL);
kfree(table->ops);
kfree(table);
return private;
......
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