From 7e5c6aa67e6f6133c5a2c53852e1dd9af2c0c3fc Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Thu, 22 May 2025 15:49:34 +0200 Subject: netfilter: nf_tables: add packets conntrack state to debug trace info Add the minimal relevant info needed for userspace ("nftables monitor trace") to provide the conntrack view of the packet: - state (new, related, established) - direction (original, reply) - status (e.g., if connection is subject to dnat) - id (allows to query ctnetlink for remaining conntrack state info) Example: trace id a62 inet filter PRE_RAW packet: iif "enp0s3" ether [..] [..] trace id a62 inet filter PRE_MANGLE conntrack: ct direction original ct state new ct id 32 trace id a62 inet filter PRE_MANGLE packet: [..] [..] trace id a62 inet filter IN conntrack: ct direction original ct state new ct status dnat-done ct id 32 [..] In this case one can see that while NAT is active, the new connection isn't subject to a translation. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- include/uapi/linux/netfilter/nf_tables.h | 8 ++++++++ 1 file changed, 8 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 7d6bc19a0153..2beb30be2c5f 100644 --- a/include/uapi/linux/netfilter/nf_tables.h +++ b/include/uapi/linux/netfilter/nf_tables.h @@ -1841,6 +1841,10 @@ enum nft_xfrm_keys { * @NFTA_TRACE_MARK: nfmark (NLA_U32) * @NFTA_TRACE_NFPROTO: nf protocol processed (NLA_U32) * @NFTA_TRACE_POLICY: policy that decided fate of packet (NLA_U32) + * @NFTA_TRACE_CT_ID: conntrack id (NLA_U32) + * @NFTA_TRACE_CT_DIRECTION: packets direction (NLA_U8) + * @NFTA_TRACE_CT_STATUS: conntrack status (NLA_U32) + * @NFTA_TRACE_CT_STATE: packet state (new, established, ...) (NLA_U32) */ enum nft_trace_attributes { NFTA_TRACE_UNSPEC, @@ -1861,6 +1865,10 @@ enum nft_trace_attributes { NFTA_TRACE_NFPROTO, NFTA_TRACE_POLICY, NFTA_TRACE_PAD, + NFTA_TRACE_CT_ID, + NFTA_TRACE_CT_DIRECTION, + NFTA_TRACE_CT_STATUS, + NFTA_TRACE_CT_STATE, __NFTA_TRACE_MAX }; #define NFTA_TRACE_MAX (__NFTA_TRACE_MAX - 1) -- cgit v1.2.3 From 465b9ee0ee7bc268d7f261356afd6c4262e48d82 Mon Sep 17 00:00:00 2001 From: Phil Sutter Date: Wed, 21 May 2025 22:44:33 +0200 Subject: netfilter: nf_tables: Add notifications for hook changes Notify user space if netdev hooks are updated due to netdev add/remove events. Send minimal notification messages by introducing NFT_MSG_NEWDEV/DELDEV message types describing a single device only. Upon NETDEV_CHANGENAME, the callback has no information about the interface's old name. To provide a clear message to user space, include the hook's stored interface name in the notification. Signed-off-by: Phil Sutter Signed-off-by: Pablo Neira Ayuso --- include/net/netfilter/nf_tables.h | 5 +++ include/uapi/linux/netfilter/nf_tables.h | 10 ++++++ include/uapi/linux/netfilter/nfnetlink.h | 2 ++ net/netfilter/nf_tables_api.c | 59 ++++++++++++++++++++++++++++++++ net/netfilter/nfnetlink.c | 1 + net/netfilter/nft_chain_filter.c | 2 ++ 6 files changed, 79 insertions(+) (limited to 'include/uapi/linux') diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h index 5e49619ae49c..e4d8e451e935 100644 --- a/include/net/netfilter/nf_tables.h +++ b/include/net/netfilter/nf_tables.h @@ -1142,6 +1142,11 @@ int nft_set_catchall_validate(const struct nft_ctx *ctx, struct nft_set *set); int nf_tables_bind_chain(const struct nft_ctx *ctx, struct nft_chain *chain); void nf_tables_unbind_chain(const struct nft_ctx *ctx, struct nft_chain *chain); +struct nft_hook; +void nf_tables_chain_device_notify(const struct nft_chain *chain, + const struct nft_hook *hook, + const struct net_device *dev, int event); + enum nft_chain_types { NFT_CHAIN_T_DEFAULT = 0, NFT_CHAIN_T_ROUTE, diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h index 2beb30be2c5f..518ba144544c 100644 --- a/include/uapi/linux/netfilter/nf_tables.h +++ b/include/uapi/linux/netfilter/nf_tables.h @@ -142,6 +142,8 @@ enum nf_tables_msg_types { NFT_MSG_DESTROYOBJ, NFT_MSG_DESTROYFLOWTABLE, NFT_MSG_GETSETELEM_RESET, + NFT_MSG_NEWDEV, + NFT_MSG_DELDEV, NFT_MSG_MAX, }; @@ -1784,10 +1786,18 @@ enum nft_synproxy_attributes { * enum nft_device_attributes - nf_tables device netlink attributes * * @NFTA_DEVICE_NAME: name of this device (NLA_STRING) + * @NFTA_DEVICE_TABLE: table containing the flowtable or chain hooking into the device (NLA_STRING) + * @NFTA_DEVICE_FLOWTABLE: flowtable hooking into the device (NLA_STRING) + * @NFTA_DEVICE_CHAIN: chain hooking into the device (NLA_STRING) + * @NFTA_DEVICE_SPEC: hook spec matching the device (NLA_STRING) */ enum nft_devices_attributes { NFTA_DEVICE_UNSPEC, NFTA_DEVICE_NAME, + NFTA_DEVICE_TABLE, + NFTA_DEVICE_FLOWTABLE, + NFTA_DEVICE_CHAIN, + NFTA_DEVICE_SPEC, __NFTA_DEVICE_MAX }; #define NFTA_DEVICE_MAX (__NFTA_DEVICE_MAX - 1) diff --git a/include/uapi/linux/netfilter/nfnetlink.h b/include/uapi/linux/netfilter/nfnetlink.h index 6cd58cd2a6f0..50d807af2649 100644 --- a/include/uapi/linux/netfilter/nfnetlink.h +++ b/include/uapi/linux/netfilter/nfnetlink.h @@ -25,6 +25,8 @@ enum nfnetlink_groups { #define NFNLGRP_ACCT_QUOTA NFNLGRP_ACCT_QUOTA NFNLGRP_NFTRACE, #define NFNLGRP_NFTRACE NFNLGRP_NFTRACE + NFNLGRP_NFT_DEV, +#define NFNLGRP_NFT_DEV NFNLGRP_NFT_DEV __NFNLGRP_MAX, }; #define NFNLGRP_MAX (__NFNLGRP_MAX - 1) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index a7240736f98e..24c71ecb2179 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -9686,6 +9686,64 @@ struct nf_hook_ops *nft_hook_find_ops_rcu(const struct nft_hook *hook, } EXPORT_SYMBOL_GPL(nft_hook_find_ops_rcu); +static void +nf_tables_device_notify(const struct nft_table *table, int attr, + const char *name, const struct nft_hook *hook, + const struct net_device *dev, int event) +{ + struct net *net = dev_net(dev); + struct nlmsghdr *nlh; + struct sk_buff *skb; + u16 flags = 0; + + if (!nfnetlink_has_listeners(net, NFNLGRP_NFT_DEV)) + return; + + skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!skb) + goto err; + + event = event == NETDEV_REGISTER ? NFT_MSG_NEWDEV : NFT_MSG_DELDEV; + event = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, event); + nlh = nfnl_msg_put(skb, 0, 0, event, flags, table->family, + NFNETLINK_V0, nft_base_seq(net)); + if (!nlh) + goto err; + + if (nla_put_string(skb, NFTA_DEVICE_TABLE, table->name) || + nla_put_string(skb, attr, name) || + nla_put(skb, NFTA_DEVICE_SPEC, hook->ifnamelen, hook->ifname) || + nla_put_string(skb, NFTA_DEVICE_NAME, dev->name)) + goto err; + + nlmsg_end(skb, nlh); + nfnetlink_send(skb, net, 0, NFNLGRP_NFT_DEV, + nlmsg_report(nlh), GFP_KERNEL); + return; +err: + if (skb) + kfree_skb(skb); + nfnetlink_set_err(net, 0, NFNLGRP_NFT_DEV, -ENOBUFS); +} + +void +nf_tables_chain_device_notify(const struct nft_chain *chain, + const struct nft_hook *hook, + const struct net_device *dev, int event) +{ + nf_tables_device_notify(chain->table, NFTA_DEVICE_CHAIN, + chain->name, hook, dev, event); +} + +static void +nf_tables_flowtable_device_notify(const struct nft_flowtable *ft, + const struct nft_hook *hook, + const struct net_device *dev, int event) +{ + nf_tables_device_notify(ft->table, NFTA_DEVICE_FLOWTABLE, + ft->name, hook, dev, event); +} + static int nft_flowtable_event(unsigned long event, struct net_device *dev, struct nft_flowtable *flowtable, bool changename) { @@ -9733,6 +9791,7 @@ static int nft_flowtable_event(unsigned long event, struct net_device *dev, list_add_tail_rcu(&ops->list, &hook->ops_list); break; } + nf_tables_flowtable_device_notify(flowtable, hook, dev, event); break; } return 0; diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c index e598a2a252b0..ac77fc21632d 100644 --- a/net/netfilter/nfnetlink.c +++ b/net/netfilter/nfnetlink.c @@ -86,6 +86,7 @@ static const int nfnl_group2type[NFNLGRP_MAX+1] = { [NFNLGRP_NFTABLES] = NFNL_SUBSYS_NFTABLES, [NFNLGRP_ACCT_QUOTA] = NFNL_SUBSYS_ACCT, [NFNLGRP_NFTRACE] = NFNL_SUBSYS_NFTABLES, + [NFNLGRP_NFT_DEV] = NFNL_SUBSYS_NFTABLES, }; static struct nfnl_net *nfnl_pernet(struct net *net) diff --git a/net/netfilter/nft_chain_filter.c b/net/netfilter/nft_chain_filter.c index b16185e9a6dd..846d48ba8965 100644 --- a/net/netfilter/nft_chain_filter.c +++ b/net/netfilter/nft_chain_filter.c @@ -363,6 +363,8 @@ static int nft_netdev_event(unsigned long event, struct net_device *dev, list_add_tail_rcu(&ops->list, &hook->ops_list); break; } + nf_tables_chain_device_notify(&basechain->chain, + hook, dev, event); break; } return 0; -- cgit v1.2.3