netfilter: nf_tables: allow chain type to override hook register

Will be used in followup patch when nat types no longer
use nf_register_net_hook() but will instead register with the nat core.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Florian Westphal 2018-05-14 23:46:55 +02:00 committed by Pablo Neira Ayuso
parent ba7d284a98
commit 4e25ceb80b
4 changed files with 47 additions and 23 deletions

View File

@ -880,8 +880,8 @@ enum nft_chain_types {
* @owner: module owner
* @hook_mask: mask of valid hooks
* @hooks: array of hook functions
* @init: chain initialization function
* @free: chain release function
* @ops_register: base chain register function
* @ops_unregister: base chain unregister function
*/
struct nft_chain_type {
const char *name;
@ -890,8 +890,8 @@ struct nft_chain_type {
struct module *owner;
unsigned int hook_mask;
nf_hookfn *hooks[NF_MAX_HOOKS];
int (*init)(struct nft_ctx *ctx);
void (*free)(struct nft_ctx *ctx);
int (*ops_register)(struct net *net, const struct nf_hook_ops *ops);
void (*ops_unregister)(struct net *net, const struct nf_hook_ops *ops);
};
int nft_chain_validate_dependency(const struct nft_chain *chain,

View File

@ -66,14 +66,21 @@ static unsigned int nft_nat_ipv4_local_fn(void *priv,
return nf_nat_ipv4_local_fn(priv, skb, state, nft_nat_do_chain);
}
static int nft_nat_ipv4_init(struct nft_ctx *ctx)
static int nft_nat_ipv4_reg(struct net *net, const struct nf_hook_ops *ops)
{
return nf_ct_netns_get(ctx->net, ctx->family);
int ret = nf_register_net_hook(net, ops);
if (ret == 0) {
ret = nf_ct_netns_get(net, NFPROTO_IPV4);
if (ret)
nf_unregister_net_hook(net, ops);
}
return ret;
}
static void nft_nat_ipv4_free(struct nft_ctx *ctx)
static void nft_nat_ipv4_unreg(struct net *net, const struct nf_hook_ops *ops)
{
nf_ct_netns_put(ctx->net, ctx->family);
nf_unregister_net_hook(net, ops);
nf_ct_netns_put(net, NFPROTO_IPV4);
}
static const struct nft_chain_type nft_chain_nat_ipv4 = {
@ -91,8 +98,8 @@ static const struct nft_chain_type nft_chain_nat_ipv4 = {
[NF_INET_LOCAL_OUT] = nft_nat_ipv4_local_fn,
[NF_INET_LOCAL_IN] = nft_nat_ipv4_fn,
},
.init = nft_nat_ipv4_init,
.free = nft_nat_ipv4_free,
.ops_register = nft_nat_ipv4_reg,
.ops_unregister = nft_nat_ipv4_unreg,
};
static int __init nft_chain_nat_init(void)

View File

@ -64,14 +64,22 @@ static unsigned int nft_nat_ipv6_local_fn(void *priv,
return nf_nat_ipv6_local_fn(priv, skb, state, nft_nat_do_chain);
}
static int nft_nat_ipv6_init(struct nft_ctx *ctx)
static int nft_nat_ipv6_reg(struct net *net, const struct nf_hook_ops *ops)
{
return nf_ct_netns_get(ctx->net, ctx->family);
int ret = nf_register_net_hook(net, ops);
if (ret == 0) {
ret = nf_ct_netns_get(net, NFPROTO_IPV6);
if (ret)
nf_unregister_net_hook(net, ops);
}
return ret;
}
static void nft_nat_ipv6_free(struct nft_ctx *ctx)
static void nft_nat_ipv6_unreg(struct net *net, const struct nf_hook_ops *ops)
{
nf_ct_netns_put(ctx->net, ctx->family);
nf_unregister_net_hook(net, ops);
nf_ct_netns_put(net, NFPROTO_IPV6);
}
static const struct nft_chain_type nft_chain_nat_ipv6 = {
@ -89,8 +97,8 @@ static const struct nft_chain_type nft_chain_nat_ipv6 = {
[NF_INET_LOCAL_OUT] = nft_nat_ipv6_local_fn,
[NF_INET_LOCAL_IN] = nft_nat_ipv6_fn,
},
.init = nft_nat_ipv6_init,
.free = nft_nat_ipv6_free,
.ops_register = nft_nat_ipv6_reg,
.ops_unregister = nft_nat_ipv6_unreg,
};
static int __init nft_chain_nat_ipv6_init(void)

View File

@ -129,6 +129,7 @@ static int nf_tables_register_hook(struct net *net,
const struct nft_table *table,
struct nft_chain *chain)
{
const struct nft_base_chain *basechain;
struct nf_hook_ops *ops;
int ret;
@ -136,7 +137,12 @@ static int nf_tables_register_hook(struct net *net,
!nft_is_base_chain(chain))
return 0;
ops = &nft_base_chain(chain)->ops;
basechain = nft_base_chain(chain);
ops = &basechain->ops;
if (basechain->type->ops_register)
return basechain->type->ops_register(net, ops);
ret = nf_register_net_hook(net, ops);
if (ret == -EBUSY && nf_tables_allow_nat_conflict(net, ops)) {
ops->nat_hook = false;
@ -151,11 +157,19 @@ static void nf_tables_unregister_hook(struct net *net,
const struct nft_table *table,
struct nft_chain *chain)
{
const struct nft_base_chain *basechain;
const struct nf_hook_ops *ops;
if (table->flags & NFT_TABLE_F_DORMANT ||
!nft_is_base_chain(chain))
return;
basechain = nft_base_chain(chain);
ops = &basechain->ops;
nf_unregister_net_hook(net, &nft_base_chain(chain)->ops);
if (basechain->type->ops_unregister)
return basechain->type->ops_unregister(net, ops);
nf_unregister_net_hook(net, ops);
}
static int nft_trans_table_add(struct nft_ctx *ctx, int msg_type)
@ -1262,8 +1276,6 @@ static void nf_tables_chain_destroy(struct nft_ctx *ctx)
if (nft_is_base_chain(chain)) {
struct nft_base_chain *basechain = nft_base_chain(chain);
if (basechain->type->free)
basechain->type->free(ctx);
module_put(basechain->type->owner);
free_percpu(basechain->stats);
if (basechain->stats)
@ -1396,9 +1408,6 @@ static int nf_tables_addchain(struct nft_ctx *ctx, u8 family, u8 genmask,
}
basechain->type = hook.type;
if (basechain->type->init)
basechain->type->init(ctx);
chain = &basechain->chain;
ops = &basechain->ops;