diff options
author | Harsha Sharma <harshasharmaiitr@gmail.com> | 2018-08-07 18:14:23 +0300 |
---|---|---|
committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2018-08-07 18:14:23 +0300 |
commit | 7e0b2b57f01d183e1c84114f1f2287737358d748 (patch) | |
tree | fbcb423c2a0ee428ff74bd18cc040eab7b809b07 /net/netfilter/nft_ct.c | |
parent | ad83f2a9ce37a264202f48f4fd8889ee9056b703 (diff) | |
download | linux-7e0b2b57f01d183e1c84114f1f2287737358d748.tar.xz |
netfilter: nft_ct: add ct timeout support
This patch allows to add, list and delete connection tracking timeout
policies via nft objref infrastructure and assigning these timeout
via nft rule.
%./libnftnl/examples/nft-ct-timeout-add ip raw cttime tcp
Ruleset:
table ip raw {
ct timeout cttime {
protocol tcp;
policy = {established: 111, close: 13 }
}
chain output {
type filter hook output priority -300; policy accept;
ct timeout set "cttime"
}
}
%./libnftnl/examples/nft-rule-ct-timeout-add ip raw output cttime
%conntrack -E
[NEW] tcp 6 111 ESTABLISHED src=172.16.19.128 dst=172.16.19.1
sport=22 dport=41360 [UNREPLIED] src=172.16.19.1 dst=172.16.19.128
sport=41360 dport=22
%nft delete rule ip raw output handle <handle>
%./libnftnl/examples/nft-ct-timeout-del ip raw cttime
Joint work with Pablo Neira.
Signed-off-by: Harsha Sharma <harshasharmaiitr@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/netfilter/nft_ct.c')
-rw-r--r-- | net/netfilter/nft_ct.c | 204 |
1 files changed, 203 insertions, 1 deletions
diff --git a/net/netfilter/nft_ct.c b/net/netfilter/nft_ct.c index 3bc82ee5464d..4788458a0931 100644 --- a/net/netfilter/nft_ct.c +++ b/net/netfilter/nft_ct.c @@ -22,6 +22,8 @@ #include <net/netfilter/nf_conntrack_helper.h> #include <net/netfilter/nf_conntrack_ecache.h> #include <net/netfilter/nf_conntrack_labels.h> +#include <net/netfilter/nf_conntrack_timeout.h> +#include <net/netfilter/nf_conntrack_l4proto.h> struct nft_ct { enum nft_ct_keys key:8; @@ -765,6 +767,194 @@ static struct nft_expr_type nft_notrack_type __read_mostly = { .owner = THIS_MODULE, }; +#ifdef CONFIG_NF_CONNTRACK_TIMEOUT +static int +nft_ct_timeout_parse_policy(void *timeouts, + const struct nf_conntrack_l4proto *l4proto, + struct net *net, const struct nlattr *attr) +{ + struct nlattr **tb; + int ret = 0; + + if (!l4proto->ctnl_timeout.nlattr_to_obj) + return 0; + + tb = kcalloc(l4proto->ctnl_timeout.nlattr_max + 1, sizeof(*tb), + GFP_KERNEL); + + if (!tb) + return -ENOMEM; + + ret = nla_parse_nested(tb, l4proto->ctnl_timeout.nlattr_max, + attr, l4proto->ctnl_timeout.nla_policy, + NULL); + if (ret < 0) + goto err; + + ret = l4proto->ctnl_timeout.nlattr_to_obj(tb, net, timeouts); + +err: + kfree(tb); + return ret; +} + +struct nft_ct_timeout_obj { + struct nf_conn *tmpl; + u8 l4proto; +}; + +static void nft_ct_timeout_obj_eval(struct nft_object *obj, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + const struct nft_ct_timeout_obj *priv = nft_obj_data(obj); + struct nf_conn *ct = (struct nf_conn *)skb_nfct(pkt->skb); + struct sk_buff *skb = pkt->skb; + + if (ct || + priv->l4proto != pkt->tprot) + return; + + nf_ct_set(skb, priv->tmpl, IP_CT_NEW); +} + +static int nft_ct_timeout_obj_init(const struct nft_ctx *ctx, + const struct nlattr * const tb[], + struct nft_object *obj) +{ + const struct nf_conntrack_zone *zone = &nf_ct_zone_dflt; + struct nft_ct_timeout_obj *priv = nft_obj_data(obj); + const struct nf_conntrack_l4proto *l4proto; + struct nf_conn_timeout *timeout_ext; + struct nf_ct_timeout *timeout; + int l3num = ctx->family; + struct nf_conn *tmpl; + __u8 l4num; + int ret; + + if (!tb[NFTA_CT_TIMEOUT_L3PROTO] || + !tb[NFTA_CT_TIMEOUT_L4PROTO] || + !tb[NFTA_CT_TIMEOUT_DATA]) + return -EINVAL; + + l3num = ntohs(nla_get_be16(tb[NFTA_CT_TIMEOUT_L3PROTO])); + l4num = nla_get_u8(tb[NFTA_CT_TIMEOUT_L4PROTO]); + priv->l4proto = l4num; + + l4proto = nf_ct_l4proto_find_get(l3num, l4num); + + if (l4proto->l4proto != l4num) { + ret = -EOPNOTSUPP; + goto err_proto_put; + } + + timeout = kzalloc(sizeof(struct nf_ct_timeout) + + l4proto->ctnl_timeout.obj_size, GFP_KERNEL); + if (timeout == NULL) { + ret = -ENOMEM; + goto err_proto_put; + } + + ret = nft_ct_timeout_parse_policy(&timeout->data, l4proto, ctx->net, + tb[NFTA_CT_TIMEOUT_DATA]); + if (ret < 0) + goto err_free_timeout; + + timeout->l3num = l3num; + timeout->l4proto = l4proto; + tmpl = nf_ct_tmpl_alloc(ctx->net, zone, GFP_ATOMIC); + if (!tmpl) { + ret = -ENOMEM; + goto err_free_timeout; + } + + timeout_ext = nf_ct_timeout_ext_add(tmpl, timeout, GFP_ATOMIC); + if (!timeout_ext) { + ret = -ENOMEM; + goto err_free_tmpl; + } + + ret = nf_ct_netns_get(ctx->net, ctx->family); + if (ret < 0) + goto err_free_tmpl; + + priv->tmpl = tmpl; + + return 0; + +err_free_tmpl: + nf_ct_tmpl_free(tmpl); +err_free_timeout: + kfree(timeout); +err_proto_put: + nf_ct_l4proto_put(l4proto); + return ret; +} + +static void nft_ct_timeout_obj_destroy(const struct nft_ctx *ctx, + struct nft_object *obj) +{ + struct nft_ct_timeout_obj *priv = nft_obj_data(obj); + struct nf_conn_timeout *t = nf_ct_timeout_find(priv->tmpl); + struct nf_ct_timeout *timeout; + + timeout = rcu_dereference_raw(t->timeout); + nf_ct_untimeout(ctx->net, timeout); + nf_ct_l4proto_put(timeout->l4proto); + nf_ct_netns_put(ctx->net, ctx->family); + nf_ct_tmpl_free(priv->tmpl); +} + +static int nft_ct_timeout_obj_dump(struct sk_buff *skb, + struct nft_object *obj, bool reset) +{ + const struct nft_ct_timeout_obj *priv = nft_obj_data(obj); + const struct nf_conn_timeout *t = nf_ct_timeout_find(priv->tmpl); + const struct nf_ct_timeout *timeout = rcu_dereference_raw(t->timeout); + struct nlattr *nest_params; + int ret; + + if (nla_put_u8(skb, NFTA_CT_TIMEOUT_L4PROTO, timeout->l4proto->l4proto) || + nla_put_be16(skb, NFTA_CT_TIMEOUT_L3PROTO, htons(timeout->l3num))) + return -1; + + nest_params = nla_nest_start(skb, NFTA_CT_TIMEOUT_DATA | NLA_F_NESTED); + if (!nest_params) + return -1; + + ret = timeout->l4proto->ctnl_timeout.obj_to_nlattr(skb, &timeout->data); + if (ret < 0) + return -1; + nla_nest_end(skb, nest_params); + return 0; +} + +static const struct nla_policy nft_ct_timeout_policy[NFTA_CT_TIMEOUT_MAX + 1] = { + [NFTA_CT_TIMEOUT_L3PROTO] = {.type = NLA_U16 }, + [NFTA_CT_TIMEOUT_L4PROTO] = {.type = NLA_U8 }, + [NFTA_CT_TIMEOUT_DATA] = {.type = NLA_NESTED }, +}; + +static struct nft_object_type nft_ct_timeout_obj_type; + +static const struct nft_object_ops nft_ct_timeout_obj_ops = { + .type = &nft_ct_timeout_obj_type, + .size = sizeof(struct nft_ct_timeout_obj), + .eval = nft_ct_timeout_obj_eval, + .init = nft_ct_timeout_obj_init, + .destroy = nft_ct_timeout_obj_destroy, + .dump = nft_ct_timeout_obj_dump, +}; + +static struct nft_object_type nft_ct_timeout_obj_type __read_mostly = { + .type = NFT_OBJECT_CT_TIMEOUT, + .ops = &nft_ct_timeout_obj_ops, + .maxattr = NFTA_CT_TIMEOUT_MAX, + .policy = nft_ct_timeout_policy, + .owner = THIS_MODULE, +}; +#endif /* CONFIG_NF_CONNTRACK_TIMEOUT */ + static int nft_ct_helper_obj_init(const struct nft_ctx *ctx, const struct nlattr * const tb[], struct nft_object *obj) @@ -949,9 +1139,17 @@ static int __init nft_ct_module_init(void) err = nft_register_obj(&nft_ct_helper_obj_type); if (err < 0) goto err2; - +#ifdef CONFIG_NF_CONNTRACK_TIMEOUT + err = nft_register_obj(&nft_ct_timeout_obj_type); + if (err < 0) + goto err3; +#endif return 0; +#ifdef CONFIG_NF_CONNTRACK_TIMEOUT +err3: + nft_unregister_obj(&nft_ct_helper_obj_type); +#endif err2: nft_unregister_expr(&nft_notrack_type); err1: @@ -961,6 +1159,9 @@ err1: static void __exit nft_ct_module_exit(void) { +#ifdef CONFIG_NF_CONNTRACK_TIMEOUT + nft_unregister_obj(&nft_ct_timeout_obj_type); +#endif nft_unregister_obj(&nft_ct_helper_obj_type); nft_unregister_expr(&nft_notrack_type); nft_unregister_expr(&nft_ct_type); @@ -974,3 +1175,4 @@ MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); MODULE_ALIAS_NFT_EXPR("ct"); MODULE_ALIAS_NFT_EXPR("notrack"); MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_CT_HELPER); +MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_CT_TIMEOUT); |