From 3206caded81ad9bdb2e7ff4c0b94ec5913df8618 Mon Sep 17 00:00:00 2001 From: Laura Garcia Liebana Date: Thu, 2 Mar 2017 17:00:14 +0100 Subject: netfilter: nft_hash: support of symmetric hash This patch provides symmetric hash support according to source ip address and port, and destination ip address and port. For this purpose, the __skb_get_hash_symmetric() is used to identify the flow as it uses FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL flag by default. The new attribute NFTA_HASH_TYPE has been included to support different types of hashing functions. Currently supported NFT_HASH_JENKINS through jhash and NFT_HASH_SYM through symhash. The main difference between both types are: - jhash requires an expression with sreg, symhash doesn't. - symhash supports modulus and offset, but not seed. Examples: nft add rule ip nat prerouting ct mark set jhash ip saddr mod 2 nft add rule ip nat prerouting ct mark set symhash mod 2 By default, jenkins hash will be used if no hash type is provided for compatibility reasons. Signed-off-by: Laura Garcia Liebana Signed-off-by: Pablo Neira Ayuso --- include/uapi/linux/netfilter/nf_tables.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h index 05215d30fe5c..4f7d75682c59 100644 --- a/include/uapi/linux/netfilter/nf_tables.h +++ b/include/uapi/linux/netfilter/nf_tables.h @@ -815,6 +815,17 @@ enum nft_rt_keys { NFT_RT_NEXTHOP6, }; +/** + * enum nft_hash_types - nf_tables hash expression types + * + * @NFT_HASH_JENKINS: Jenkins Hash + * @NFT_HASH_SYM: Symmetric Hash + */ +enum nft_hash_types { + NFT_HASH_JENKINS, + NFT_HASH_SYM, +}; + /** * enum nft_hash_attributes - nf_tables hash expression netlink attributes * @@ -824,6 +835,7 @@ enum nft_rt_keys { * @NFTA_HASH_MODULUS: modulus value (NLA_U32) * @NFTA_HASH_SEED: seed value (NLA_U32) * @NFTA_HASH_OFFSET: add this offset value to hash result (NLA_U32) + * @NFTA_HASH_TYPE: hash operation (NLA_U32: nft_hash_types) */ enum nft_hash_attributes { NFTA_HASH_UNSPEC, @@ -833,6 +845,7 @@ enum nft_hash_attributes { NFTA_HASH_MODULUS, NFTA_HASH_SEED, NFTA_HASH_OFFSET, + NFTA_HASH_TYPE, __NFTA_HASH_MAX, }; #define NFTA_HASH_MAX (__NFTA_HASH_MAX - 1) -- cgit v1.2.3 From 1a64edf54f55d7956cf5a0d95898bc1f84f9b818 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Wed, 8 Mar 2017 16:48:44 +0100 Subject: netfilter: nft_ct: add helper set support this allows to assign connection tracking helpers to connections via nft objref infrastructure. The idea is to first specifiy a helper object: table ip filter { ct helper some-name { type "ftp" protocol tcp l3proto ip } } and then assign it via nft add ... ct helper set "some-name" helper assignment works for new conntracks only as we cannot expand the conntrack extension area once it has been committed to the main conntrack table. ipv4 and ipv6 protocols are tracked stored separately so we can also handle families that observe both ipv4 and ipv6 traffic. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- include/uapi/linux/netfilter/nf_tables.h | 12 ++- net/netfilter/nft_ct.c | 171 +++++++++++++++++++++++++++++++ 2 files changed, 182 insertions(+), 1 deletion(-) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h index 4f7d75682c59..34c8d08b687a 100644 --- a/include/uapi/linux/netfilter/nf_tables.h +++ b/include/uapi/linux/netfilter/nf_tables.h @@ -1259,10 +1259,20 @@ enum nft_fib_flags { NFTA_FIB_F_OIF = 1 << 4, /* restrict to oif */ }; +enum nft_ct_helper_attributes { + NFTA_CT_HELPER_UNSPEC, + NFTA_CT_HELPER_NAME, + NFTA_CT_HELPER_L3PROTO, + NFTA_CT_HELPER_L4PROTO, + __NFTA_CT_HELPER_MAX, +}; +#define NFTA_CT_HELPER_MAX (__NFTA_CT_HELPER_MAX - 1) + #define NFT_OBJECT_UNSPEC 0 #define NFT_OBJECT_COUNTER 1 #define NFT_OBJECT_QUOTA 2 -#define __NFT_OBJECT_MAX 3 +#define NFT_OBJECT_CT_HELPER 3 +#define __NFT_OBJECT_MAX 4 #define NFT_OBJECT_MAX (__NFT_OBJECT_MAX - 1) /** diff --git a/net/netfilter/nft_ct.c b/net/netfilter/nft_ct.c index bf548a7a71ec..4144ae845bdd 100644 --- a/net/netfilter/nft_ct.c +++ b/net/netfilter/nft_ct.c @@ -32,6 +32,12 @@ struct nft_ct { }; }; +struct nft_ct_helper_obj { + struct nf_conntrack_helper *helper4; + struct nf_conntrack_helper *helper6; + u8 l4proto; +}; + #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; @@ -730,6 +736,162 @@ static struct nft_expr_type nft_notrack_type __read_mostly = { .owner = THIS_MODULE, }; +static int nft_ct_helper_obj_init(const struct nft_ctx *ctx, + const struct nlattr * const tb[], + struct nft_object *obj) +{ + struct nft_ct_helper_obj *priv = nft_obj_data(obj); + struct nf_conntrack_helper *help4, *help6; + char name[NF_CT_HELPER_NAME_LEN]; + int family = ctx->afi->family; + + if (!tb[NFTA_CT_HELPER_NAME] || !tb[NFTA_CT_HELPER_L4PROTO]) + return -EINVAL; + + priv->l4proto = nla_get_u8(tb[NFTA_CT_HELPER_L4PROTO]); + if (!priv->l4proto) + return -ENOENT; + + nla_strlcpy(name, tb[NFTA_CT_HELPER_NAME], sizeof(name)); + + if (tb[NFTA_CT_HELPER_L3PROTO]) + family = ntohs(nla_get_be16(tb[NFTA_CT_HELPER_L3PROTO])); + + help4 = NULL; + help6 = NULL; + + switch (family) { + case NFPROTO_IPV4: + if (ctx->afi->family == NFPROTO_IPV6) + return -EINVAL; + + help4 = nf_conntrack_helper_try_module_get(name, family, + priv->l4proto); + break; + case NFPROTO_IPV6: + if (ctx->afi->family == NFPROTO_IPV4) + return -EINVAL; + + help6 = nf_conntrack_helper_try_module_get(name, family, + priv->l4proto); + break; + case NFPROTO_NETDEV: /* fallthrough */ + case NFPROTO_BRIDGE: /* same */ + case NFPROTO_INET: + help4 = nf_conntrack_helper_try_module_get(name, NFPROTO_IPV4, + priv->l4proto); + help6 = nf_conntrack_helper_try_module_get(name, NFPROTO_IPV6, + priv->l4proto); + break; + default: + return -EAFNOSUPPORT; + } + + /* && is intentional; only error if INET found neither ipv4 or ipv6 */ + if (!help4 && !help6) + return -ENOENT; + + priv->helper4 = help4; + priv->helper6 = help6; + + return 0; +} + +static void nft_ct_helper_obj_destroy(struct nft_object *obj) +{ + struct nft_ct_helper_obj *priv = nft_obj_data(obj); + + if (priv->helper4) + module_put(priv->helper4->me); + if (priv->helper6) + module_put(priv->helper6->me); +} + +static void nft_ct_helper_obj_eval(struct nft_object *obj, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + const struct nft_ct_helper_obj *priv = nft_obj_data(obj); + struct nf_conn *ct = (struct nf_conn *)skb_nfct(pkt->skb); + struct nf_conntrack_helper *to_assign = NULL; + struct nf_conn_help *help; + + if (!ct || + nf_ct_is_confirmed(ct) || + nf_ct_is_template(ct) || + priv->l4proto != nf_ct_protonum(ct)) + return; + + switch (nf_ct_l3num(ct)) { + case NFPROTO_IPV4: + to_assign = priv->helper4; + break; + case NFPROTO_IPV6: + to_assign = priv->helper6; + break; + default: + WARN_ON_ONCE(1); + return; + } + + if (!to_assign) + return; + + if (test_bit(IPS_HELPER_BIT, &ct->status)) + return; + + help = nf_ct_helper_ext_add(ct, to_assign, GFP_ATOMIC); + if (help) { + rcu_assign_pointer(help->helper, to_assign); + set_bit(IPS_HELPER_BIT, &ct->status); + } +} + +static int nft_ct_helper_obj_dump(struct sk_buff *skb, + struct nft_object *obj, bool reset) +{ + const struct nft_ct_helper_obj *priv = nft_obj_data(obj); + const struct nf_conntrack_helper *helper = priv->helper4; + u16 family; + + if (nla_put_string(skb, NFTA_CT_HELPER_NAME, helper->name)) + return -1; + + if (nla_put_u8(skb, NFTA_CT_HELPER_L4PROTO, priv->l4proto)) + return -1; + + if (priv->helper4 && priv->helper6) + family = NFPROTO_INET; + else if (priv->helper6) + family = NFPROTO_IPV6; + else + family = NFPROTO_IPV4; + + if (nla_put_be16(skb, NFTA_CT_HELPER_L3PROTO, htons(family))) + return -1; + + return 0; +} + +static const struct nla_policy nft_ct_helper_policy[NFTA_CT_HELPER_MAX + 1] = { + [NFTA_CT_HELPER_NAME] = { .type = NLA_STRING, + .len = NF_CT_HELPER_NAME_LEN - 1 }, + [NFTA_CT_HELPER_L3PROTO] = { .type = NLA_U16 }, + [NFTA_CT_HELPER_L4PROTO] = { .type = NLA_U8 }, +}; + +static struct nft_object_type nft_ct_helper_obj __read_mostly = { + .type = NFT_OBJECT_CT_HELPER, + .size = sizeof(struct nft_ct_helper_obj), + .maxattr = NFTA_CT_HELPER_MAX, + .policy = nft_ct_helper_policy, + .eval = nft_ct_helper_obj_eval, + .init = nft_ct_helper_obj_init, + .destroy = nft_ct_helper_obj_destroy, + .dump = nft_ct_helper_obj_dump, + .owner = THIS_MODULE, +}; + static int __init nft_ct_module_init(void) { int err; @@ -744,7 +906,14 @@ static int __init nft_ct_module_init(void) if (err < 0) goto err1; + err = nft_register_obj(&nft_ct_helper_obj); + if (err < 0) + goto err2; + return 0; + +err2: + nft_unregister_expr(&nft_notrack_type); err1: nft_unregister_expr(&nft_ct_type); return err; @@ -752,6 +921,7 @@ err1: static void __exit nft_ct_module_exit(void) { + nft_unregister_obj(&nft_ct_helper_obj); nft_unregister_expr(&nft_notrack_type); nft_unregister_expr(&nft_ct_type); } @@ -763,3 +933,4 @@ MODULE_LICENSE("GPL"); MODULE_AUTHOR("Patrick McHardy "); MODULE_ALIAS_NFT_EXPR("ct"); MODULE_ALIAS_NFT_EXPR("notrack"); +MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_CT_HELPER); -- cgit v1.2.3 From 055c4b34b94f696d9bd9aad53a11378a0fc409c9 Mon Sep 17 00:00:00 2001 From: Phil Sutter Date: Fri, 10 Mar 2017 18:08:02 +0100 Subject: netfilter: nft_fib: Support existence check Instead of the actual interface index or name, set destination register to just 1 or 0 depending on whether the lookup succeeded or not if NFTA_FIB_F_PRESENT was set in userspace. Signed-off-by: Phil Sutter Signed-off-by: Pablo Neira Ayuso --- include/net/netfilter/nft_fib.h | 2 +- include/uapi/linux/netfilter/nf_tables.h | 1 + net/ipv4/netfilter/nft_fib_ipv4.c | 4 ++-- net/ipv6/netfilter/nft_fib_ipv6.c | 2 +- net/netfilter/nft_fib.c | 14 +++++++++----- 5 files changed, 14 insertions(+), 9 deletions(-) (limited to 'include/uapi/linux') diff --git a/include/net/netfilter/nft_fib.h b/include/net/netfilter/nft_fib.h index 5ceb2205e4e3..381af9469e6a 100644 --- a/include/net/netfilter/nft_fib.h +++ b/include/net/netfilter/nft_fib.h @@ -32,6 +32,6 @@ void nft_fib6_eval_type(const struct nft_expr *expr, struct nft_regs *regs, void nft_fib6_eval(const struct nft_expr *expr, struct nft_regs *regs, const struct nft_pktinfo *pkt); -void nft_fib_store_result(void *reg, enum nft_fib_result r, +void nft_fib_store_result(void *reg, const struct nft_fib *priv, const struct nft_pktinfo *pkt, int index); #endif diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h index 34c8d08b687a..8f3842690d17 100644 --- a/include/uapi/linux/netfilter/nf_tables.h +++ b/include/uapi/linux/netfilter/nf_tables.h @@ -1257,6 +1257,7 @@ enum nft_fib_flags { NFTA_FIB_F_MARK = 1 << 2, /* use skb->mark */ NFTA_FIB_F_IIF = 1 << 3, /* restrict to iif */ NFTA_FIB_F_OIF = 1 << 4, /* restrict to oif */ + NFTA_FIB_F_PRESENT = 1 << 5, /* check existence only */ }; enum nft_ct_helper_attributes { diff --git a/net/ipv4/netfilter/nft_fib_ipv4.c b/net/ipv4/netfilter/nft_fib_ipv4.c index 2981291910dd..f4e4462cb5bb 100644 --- a/net/ipv4/netfilter/nft_fib_ipv4.c +++ b/net/ipv4/netfilter/nft_fib_ipv4.c @@ -90,7 +90,7 @@ void nft_fib4_eval(const struct nft_expr *expr, struct nft_regs *regs, if (nft_hook(pkt) == NF_INET_PRE_ROUTING && nft_fib_is_loopback(pkt->skb, nft_in(pkt))) { - nft_fib_store_result(dest, priv->result, pkt, + nft_fib_store_result(dest, priv, pkt, nft_in(pkt)->ifindex); return; } @@ -99,7 +99,7 @@ void nft_fib4_eval(const struct nft_expr *expr, struct nft_regs *regs, if (ipv4_is_zeronet(iph->saddr)) { if (ipv4_is_lbcast(iph->daddr) || ipv4_is_local_multicast(iph->daddr)) { - nft_fib_store_result(dest, priv->result, pkt, + nft_fib_store_result(dest, priv, pkt, get_ifindex(pkt->skb->dev)); return; } diff --git a/net/ipv6/netfilter/nft_fib_ipv6.c b/net/ipv6/netfilter/nft_fib_ipv6.c index 765facf03d45..e8d88d82636b 100644 --- a/net/ipv6/netfilter/nft_fib_ipv6.c +++ b/net/ipv6/netfilter/nft_fib_ipv6.c @@ -159,7 +159,7 @@ void nft_fib6_eval(const struct nft_expr *expr, struct nft_regs *regs, if (nft_hook(pkt) == NF_INET_PRE_ROUTING && nft_fib_is_loopback(pkt->skb, nft_in(pkt))) { - nft_fib_store_result(dest, priv->result, pkt, + nft_fib_store_result(dest, priv, pkt, nft_in(pkt)->ifindex); return; } diff --git a/net/netfilter/nft_fib.c b/net/netfilter/nft_fib.c index fd0b19303b0d..21df8cccea65 100644 --- a/net/netfilter/nft_fib.c +++ b/net/netfilter/nft_fib.c @@ -24,7 +24,8 @@ const struct nla_policy nft_fib_policy[NFTA_FIB_MAX + 1] = { EXPORT_SYMBOL(nft_fib_policy); #define NFTA_FIB_F_ALL (NFTA_FIB_F_SADDR | NFTA_FIB_F_DADDR | \ - NFTA_FIB_F_MARK | NFTA_FIB_F_IIF | NFTA_FIB_F_OIF) + NFTA_FIB_F_MARK | NFTA_FIB_F_IIF | NFTA_FIB_F_OIF | \ + NFTA_FIB_F_PRESENT) int nft_fib_validate(const struct nft_ctx *ctx, const struct nft_expr *expr, const struct nft_data **data) @@ -133,19 +134,22 @@ int nft_fib_dump(struct sk_buff *skb, const struct nft_expr *expr) } EXPORT_SYMBOL_GPL(nft_fib_dump); -void nft_fib_store_result(void *reg, enum nft_fib_result r, +void nft_fib_store_result(void *reg, const struct nft_fib *priv, const struct nft_pktinfo *pkt, int index) { struct net_device *dev; u32 *dreg = reg; - switch (r) { + switch (priv->result) { case NFT_FIB_RESULT_OIF: - *dreg = index; + *dreg = (priv->flags & NFTA_FIB_F_PRESENT) ? !!index : index; break; case NFT_FIB_RESULT_OIFNAME: dev = dev_get_by_index_rcu(nft_net(pkt), index); - strncpy(reg, dev ? dev->name : "", IFNAMSIZ); + if (priv->flags & NFTA_FIB_F_PRESENT) + *dreg = !!dev; + else + strncpy(reg, dev ? dev->name : "", IFNAMSIZ); break; default: WARN_ON_ONCE(1); -- cgit v1.2.3