diff options
Diffstat (limited to 'net/netfilter/nft_ct.c')
| -rw-r--r-- | net/netfilter/nft_ct.c | 142 |
1 files changed, 140 insertions, 2 deletions
diff --git a/net/netfilter/nft_ct.c b/net/netfilter/nft_ct.c index dfcdea6619f1..827ab6196df9 100644 --- a/net/netfilter/nft_ct.c +++ b/net/netfilter/nft_ct.c @@ -21,6 +21,7 @@ #include <net/netfilter/nf_conntrack_labels.h> #include <net/netfilter/nf_conntrack_timeout.h> #include <net/netfilter/nf_conntrack_l4proto.h> +#include <net/netfilter/nf_conntrack_expect.h> struct nft_ct { enum nft_ct_keys key:8; @@ -1153,6 +1154,135 @@ static struct nft_object_type nft_ct_helper_obj_type __read_mostly = { .owner = THIS_MODULE, }; +struct nft_ct_expect_obj { + u16 l3num; + __be16 dport; + u8 l4proto; + u8 size; + u32 timeout; +}; + +static int nft_ct_expect_obj_init(const struct nft_ctx *ctx, + const struct nlattr * const tb[], + struct nft_object *obj) +{ + struct nft_ct_expect_obj *priv = nft_obj_data(obj); + + if (!tb[NFTA_CT_EXPECT_L4PROTO] || + !tb[NFTA_CT_EXPECT_DPORT] || + !tb[NFTA_CT_EXPECT_TIMEOUT] || + !tb[NFTA_CT_EXPECT_SIZE]) + return -EINVAL; + + priv->l3num = ctx->family; + if (tb[NFTA_CT_EXPECT_L3PROTO]) + priv->l3num = ntohs(nla_get_be16(tb[NFTA_CT_EXPECT_L3PROTO])); + + priv->l4proto = nla_get_u8(tb[NFTA_CT_EXPECT_L4PROTO]); + priv->dport = nla_get_be16(tb[NFTA_CT_EXPECT_DPORT]); + priv->timeout = nla_get_u32(tb[NFTA_CT_EXPECT_TIMEOUT]); + priv->size = nla_get_u8(tb[NFTA_CT_EXPECT_SIZE]); + + return nf_ct_netns_get(ctx->net, ctx->family); +} + +static void nft_ct_expect_obj_destroy(const struct nft_ctx *ctx, + struct nft_object *obj) +{ + nf_ct_netns_put(ctx->net, ctx->family); +} + +static int nft_ct_expect_obj_dump(struct sk_buff *skb, + struct nft_object *obj, bool reset) +{ + const struct nft_ct_expect_obj *priv = nft_obj_data(obj); + + if (nla_put_be16(skb, NFTA_CT_EXPECT_L3PROTO, htons(priv->l3num)) || + nla_put_u8(skb, NFTA_CT_EXPECT_L4PROTO, priv->l4proto) || + nla_put_be16(skb, NFTA_CT_EXPECT_DPORT, priv->dport) || + nla_put_u32(skb, NFTA_CT_EXPECT_TIMEOUT, priv->timeout) || + nla_put_u8(skb, NFTA_CT_EXPECT_SIZE, priv->size)) + return -1; + + return 0; +} + +static void nft_ct_expect_obj_eval(struct nft_object *obj, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + const struct nft_ct_expect_obj *priv = nft_obj_data(obj); + struct nf_conntrack_expect *exp; + enum ip_conntrack_info ctinfo; + struct nf_conn_help *help; + enum ip_conntrack_dir dir; + u16 l3num = priv->l3num; + struct nf_conn *ct; + + ct = nf_ct_get(pkt->skb, &ctinfo); + if (!ct || ctinfo == IP_CT_UNTRACKED) { + regs->verdict.code = NFT_BREAK; + return; + } + dir = CTINFO2DIR(ctinfo); + + help = nfct_help(ct); + if (!help) + help = nf_ct_helper_ext_add(ct, GFP_ATOMIC); + if (!help) { + regs->verdict.code = NF_DROP; + return; + } + + if (help->expecting[NF_CT_EXPECT_CLASS_DEFAULT] >= priv->size) { + regs->verdict.code = NFT_BREAK; + return; + } + if (l3num == NFPROTO_INET) + l3num = nf_ct_l3num(ct); + + exp = nf_ct_expect_alloc(ct); + if (exp == NULL) { + regs->verdict.code = NF_DROP; + return; + } + nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, l3num, + &ct->tuplehash[!dir].tuple.src.u3, + &ct->tuplehash[!dir].tuple.dst.u3, + priv->l4proto, NULL, &priv->dport); + exp->timeout.expires = jiffies + priv->timeout * HZ; + + if (nf_ct_expect_related(exp) != 0) + regs->verdict.code = NF_DROP; +} + +static const struct nla_policy nft_ct_expect_policy[NFTA_CT_EXPECT_MAX + 1] = { + [NFTA_CT_EXPECT_L3PROTO] = { .type = NLA_U16 }, + [NFTA_CT_EXPECT_L4PROTO] = { .type = NLA_U8 }, + [NFTA_CT_EXPECT_DPORT] = { .type = NLA_U16 }, + [NFTA_CT_EXPECT_TIMEOUT] = { .type = NLA_U32 }, + [NFTA_CT_EXPECT_SIZE] = { .type = NLA_U8 }, +}; + +static struct nft_object_type nft_ct_expect_obj_type; + +static const struct nft_object_ops nft_ct_expect_obj_ops = { + .type = &nft_ct_expect_obj_type, + .size = sizeof(struct nft_ct_expect_obj), + .eval = nft_ct_expect_obj_eval, + .init = nft_ct_expect_obj_init, + .destroy = nft_ct_expect_obj_destroy, + .dump = nft_ct_expect_obj_dump, +}; + +static struct nft_object_type nft_ct_expect_obj_type __read_mostly = { + .type = NFT_OBJECT_CT_EXPECT, + .ops = &nft_ct_expect_obj_ops, + .maxattr = NFTA_CT_EXPECT_MAX, + .policy = nft_ct_expect_policy, + .owner = THIS_MODULE, +}; + static int __init nft_ct_module_init(void) { int err; @@ -1170,17 +1300,23 @@ static int __init nft_ct_module_init(void) err = nft_register_obj(&nft_ct_helper_obj_type); if (err < 0) goto err2; + + err = nft_register_obj(&nft_ct_expect_obj_type); + if (err < 0) + goto err3; #ifdef CONFIG_NF_CONNTRACK_TIMEOUT err = nft_register_obj(&nft_ct_timeout_obj_type); if (err < 0) - goto err3; + goto err4; #endif return 0; #ifdef CONFIG_NF_CONNTRACK_TIMEOUT +err4: + nft_unregister_obj(&nft_ct_expect_obj_type); +#endif err3: nft_unregister_obj(&nft_ct_helper_obj_type); -#endif err2: nft_unregister_expr(&nft_notrack_type); err1: @@ -1193,6 +1329,7 @@ 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_expect_obj_type); nft_unregister_obj(&nft_ct_helper_obj_type); nft_unregister_expr(&nft_notrack_type); nft_unregister_expr(&nft_ct_type); @@ -1207,3 +1344,4 @@ 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); +MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_CT_EXPECT); |