This patch allows to add, list and delete connection tracking timeout policies via nft objref infrastructure and assigning these timeout via nft rule.
Ruleset: table ip raw { ct timeout cttime { protocol tcp established 111 close 13 l3proto ip } chain output { type filter hook output priority -300; policy accept; ct timeout set "cttime" } } %./libnftnl/examples/nft-ct-timeout-add ip raw cttime tcp %./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 zone=4 Signed-off-by: Harsha Sharma <harshasharmai...@gmail.com> --- Changes in v5: - wrap with NF_CT_NETLINK_TIMEOUT option - attach timeout template in init - other minor changes Changes in v4: - Remove unused attributes - allocate template from init() path - minor changes - updated log message - pull to latest tree Changes in v3: - Use nf_ct_tmpl_alloc to attach timeout via template conntrack. Changes in v2: - Add code for nft_ct_timeout_obj_eval - remove likely() from code - remove vla in ctnl_timeout_parse_policy include/net/netfilter/nf_conntrack_timeout.h | 1 + include/uapi/linux/netfilter/nf_tables.h | 14 +- net/netfilter/nft_ct.c | 203 ++++++++++++++++++++++++++- 3 files changed, 215 insertions(+), 3 deletions(-) diff --git a/include/net/netfilter/nf_conntrack_timeout.h b/include/net/netfilter/nf_conntrack_timeout.h index 80ceb3d0291d..c3b81a82b3c9 100644 --- a/include/net/netfilter/nf_conntrack_timeout.h +++ b/include/net/netfilter/nf_conntrack_timeout.h @@ -8,6 +8,7 @@ #include <linux/refcount.h> #include <net/netfilter/nf_conntrack.h> #include <net/netfilter/nf_conntrack_extend.h> +#include <net/netfilter/nf_conntrack_l4proto.h> #define CTNL_TIMEOUT_NAME_MAX 32 diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h index 89438e68dc03..552fa5a6b7c3 100644 --- a/include/uapi/linux/netfilter/nf_tables.h +++ b/include/uapi/linux/netfilter/nf_tables.h @@ -955,6 +955,7 @@ enum nft_socket_keys { * @NFT_CT_DST_IP: conntrack layer 3 protocol destination (IPv4 address) * @NFT_CT_SRC_IP6: conntrack layer 3 protocol source (IPv6 address) * @NFT_CT_DST_IP6: conntrack layer 3 protocol destination (IPv6 address) + * @NFT_CT_TIMEOUT: connection tracking timeout policy assigned to conntrack */ enum nft_ct_keys { NFT_CT_STATE, @@ -980,6 +981,7 @@ enum nft_ct_keys { NFT_CT_DST_IP, NFT_CT_SRC_IP6, NFT_CT_DST_IP6, + NFT_CT_TIMEOUT, __NFT_CT_MAX }; #define NFT_CT_MAX (__NFT_CT_MAX - 1) @@ -1392,13 +1394,23 @@ enum nft_ct_helper_attributes { }; #define NFTA_CT_HELPER_MAX (__NFTA_CT_HELPER_MAX - 1) +enum nft_ct_timeout_timeout_attributes { + NFTA_CT_TIMEOUT_UNSPEC, + NFTA_CT_TIMEOUT_L3PROTO, + NFTA_CT_TIMEOUT_L4PROTO, + NFTA_CT_TIMEOUT_DATA, + __NFTA_CT_TIMEOUT_MAX, +}; +#define NFTA_CT_TIMEOUT_MAX (__NFTA_CT_TIMEOUT_MAX - 1) + #define NFT_OBJECT_UNSPEC 0 #define NFT_OBJECT_COUNTER 1 #define NFT_OBJECT_QUOTA 2 #define NFT_OBJECT_CT_HELPER 3 #define NFT_OBJECT_LIMIT 4 #define NFT_OBJECT_CONNLIMIT 5 -#define __NFT_OBJECT_MAX 6 +#define NFT_OBJECT_CT_TIMEOUT 6 +#define __NFT_OBJECT_MAX 7 #define NFT_OBJECT_MAX (__NFT_OBJECT_MAX - 1) /** diff --git a/net/netfilter/nft_ct.c b/net/netfilter/nft_ct.c index 1435ffc5f57e..40678a2e65a4 100644 --- a/net/netfilter/nft_ct.c +++ b/net/netfilter/nft_ct.c @@ -22,6 +22,9 @@ #include <net/netfilter/nf_conntrack_helper.h> #include <net/netfilter/nf_conntrack_ecache.h> #include <net/netfilter/nf_conntrack_labels.h> +#include <linux/netfilter/nfnetlink_cttimeout.h> +#include <net/netfilter/nf_conntrack_timeout.h> +#include <net/netfilter/nf_conntrack_l4proto.h> struct nft_ct { enum nft_ct_keys key:8; @@ -32,12 +35,18 @@ struct nft_ct { }; }; -struct nft_ct_helper_obj { +struct nft_ct_helper_obj { struct nf_conntrack_helper *helper4; struct nf_conntrack_helper *helper6; u8 l4proto; }; +struct nft_ct_timeout_obj { + struct ctnl_timeout *timeout; + struct nf_conn *tmpl; + struct nf_conn_timeout *ext; +}; + #ifdef CONFIG_NF_CONNTRACK_ZONES static DEFINE_PER_CPU(struct nf_conn *, nft_ct_pcpu_template); static unsigned int nft_ct_pcpu_template_refcnt __read_mostly; @@ -412,7 +421,6 @@ static int nft_ct_get_init(const struct nft_ctx *ctx, return -EINVAL; len = NF_CT_HELPER_NAME_LEN; break; - case NFT_CT_L3PROTOCOL: case NFT_CT_PROTOCOL: /* For compatibility, do not report error if NFTA_CT_DIRECTION @@ -765,6 +773,168 @@ static struct nft_expr_type nft_notrack_type __read_mostly = { .owner = THIS_MODULE, }; +#ifdef CONFIG_NF_CT_NETLINK_TIMEOUT +static int +ctnl_timeout_parse_policy(void *timeouts, + const struct nf_conntrack_l4proto *l4proto, + struct net *net, const struct nlattr *attr) +{ + int ret = 0; + struct nlattr **tb; + + 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; +} + +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 ctnl_timeout *to_assign = NULL; + struct sk_buff *skb = pkt->skb; + enum ip_conntrack_info ctinfo; + + if (!priv->tmpl) + return; + + to_assign = priv->timeout; + + if (!nf_ct_get(skb, &ctinfo)) + nf_ct_set(skb, priv->tmpl, IP_CT_NEW); + + if (priv->ext) + rcu_assign_pointer(priv->ext->timeout, to_assign); +} + +static int nft_ct_timeout_obj_init(const struct nft_ctx *ctx, + const struct nlattr * const tb[], + struct nft_object *obj) +{ + __u8 l4num; + struct nft_ct_timeout_obj *priv = nft_obj_data(obj); + const struct nf_conntrack_l4proto *l4proto; + struct ctnl_timeout *timeout, *matching = NULL; + struct nf_conn *tmpl; + const struct nf_conntrack_zone *zone = &nf_ct_zone_dflt; + int ret; + int l3num = ctx->family; + struct nf_conn_timeout *timeout_ext; + + if (!tb[NFTA_CT_TIMEOUT_L4PROTO] || + !tb[NFTA_CT_TIMEOUT_DATA]) + return -EINVAL; + + if (tb[NFTA_CT_TIMEOUT_L3PROTO]) + l3num = ntohs(nla_get_be16(tb[NFTA_CT_TIMEOUT_L3PROTO])); + l4num = nla_get_u8(tb[NFTA_CT_TIMEOUT_L4PROTO]); + + INIT_LIST_HEAD(&ctx->net->nfct_timeout_list); + list_for_each_entry(timeout, &ctx->net->nfct_timeout_list, head) { + matching = timeout; + break; + } + + if (matching) { + if (matching->l3num != l3num || + matching->l4proto->l4proto != l4num) + return -EINVAL; + return ctnl_timeout_parse_policy(&matching->data, + matching->l4proto, ctx->net, + tb[NFTA_CT_TIMEOUT_DATA]); + } + + l4proto = nf_ct_l4proto_find_get(l3num, l4num); + + if (l4proto->l4proto != l4num) { + ret = -EOPNOTSUPP; + goto err_proto_put; + } + + timeout = kzalloc(sizeof(struct ctnl_timeout) + + l4proto->ctnl_timeout.obj_size, GFP_KERNEL); + if (timeout == NULL) { + ret = -ENOMEM; + goto err_proto_put; + } + + ret = ctnl_timeout_parse_policy(&timeout->data, l4proto, ctx->net, + tb[NFTA_CT_TIMEOUT_DATA]); + if (ret < 0) + goto err; + timeout->l3num = l3num; + timeout->l4proto = l4proto; + list_add_tail_rcu(&timeout->head, &ctx->net->nfct_timeout_list); + priv->timeout = timeout; + tmpl = nf_ct_tmpl_alloc(ctx->net, zone, GFP_ATOMIC); + tmpl->zone.id = 4; + priv->tmpl = tmpl; + timeout_ext = nf_ct_timeout_ext_add(priv->tmpl, priv->timeout, GFP_ATOMIC); + priv->ext = timeout_ext; + + return 0; + +err: + 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); + + if (refcount_dec_if_one(&priv->timeout->refcnt)) { + nf_ct_l4proto_put(priv->timeout->l4proto); + list_del_rcu(&priv->timeout->head); + 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 ctnl_timeout *timeout = priv->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(priv->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; +} +#endif + static int nft_ct_helper_obj_init(const struct nft_ctx *ctx, const struct nlattr * const tb[], struct nft_object *obj) @@ -932,6 +1102,30 @@ static struct nft_object_type nft_ct_helper_obj_type __read_mostly = { .owner = THIS_MODULE, }; +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, +}; + static int __init nft_ct_module_init(void) { int err; @@ -947,6 +1141,9 @@ static int __init nft_ct_module_init(void) goto err1; err = nft_register_obj(&nft_ct_helper_obj_type); + if (err < 0) + goto err2; + err = nft_register_obj(&nft_ct_timeout_obj_type); if (err < 0) goto err2; @@ -962,6 +1159,7 @@ static int __init nft_ct_module_init(void) static void __exit nft_ct_module_exit(void) { nft_unregister_obj(&nft_ct_helper_obj_type); + nft_unregister_obj(&nft_ct_timeout_obj_type); nft_unregister_expr(&nft_notrack_type); nft_unregister_expr(&nft_ct_type); } @@ -974,3 +1172,4 @@ MODULE_AUTHOR("Patrick McHardy <ka...@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); -- 2.14.1 -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html