kernel/linux.git/net/netfilter/Makefile, branch v6.6.132

bpf: add bpf_link support for BPF_NETFILTER programs

2023-04-21T18:34:14+00:00

Add bpf_link support skeleton. To keep this reviewable, no bpf program can be invoked yet, if a program is attached only a c-stub is called and not the actual bpf program. Defaults to 'y' if both netfilter and bpf syscall are enabled in kconfig. Uapi example usage: union bpf_attr attr = { }; attr.link_create.prog_fd = progfd; attr.link_create.attach_type = 0; /* unused */ attr.link_create.netfilter.pf = PF_INET; attr.link_create.netfilter.hooknum = NF_INET_LOCAL_IN; attr.link_create.netfilter.priority = -128; err = bpf(BPF_LINK_CREATE, &attr, sizeof(attr)); ... this would attach progfd to ipv4:input hook. Such hook gets removed automatically if the calling program exits. BPF_NETFILTER program invocation is added in followup change. NF_HOOK_OP_BPF enum will eventually be read from nfnetlink_hook, it allows to tell userspace which program is attached at the given hook when user runs 'nft hook list' command rather than just the priority and not-very-helpful 'this hook runs a bpf prog but I can't tell which one'. Will also be used to disallow registration of two bpf programs with same priority in a followup patch. v4: arm32 cmpxchg only supports 32bit operand s/prio/priority/ v3: restrict prog attachment to ip/ip6 for now, lets lift restrictions if more use cases pop up (arptables, ebtables, netdev ingress/egress etc). Signed-off-by: Florian Westphal Link: https://lore.kernel.org/r/20230421170300.24115-2-fw@strlen.de Signed-off-by: Alexei Starovoitov

net: create nf_conntrack_ovs for ovs and tc use

2023-02-11T00:23:03+00:00

Similar to nf_nat_ovs created by Commit ebddb1404900 ("net: move the nat function to nf_nat_ovs for ovs and tc"), this patch is to create nf_conntrack_ovs to get these functions shared by OVS and TC only. There are nf_ct_helper() and nf_ct_add_helper() from nf_conntrak_helper in this patch, and will be more in the following patches. Signed-off-by: Xin Long Reviewed-by: Simon Horman Reviewed-by: Aaron Conole Acked-by: Florian Westphal Signed-off-by: Jakub Kicinski

netfilter: nf_tables: avoid retpoline overhead for some ct expression calls

2023-01-18T12:05:25+00:00

nft_ct expression cannot be made builtin to nf_tables without also forcing the conntrack itself to be builtin. However, this can be avoided by splitting retrieval of a few selector keys that only need to access the nf_conn structure, i.e. no function calls to nf_conntrack code. Many rulesets start with something like "ct status established,related accept" With this change, this no longer requires an indirect call, which gives about 1.8% more throughput with a simple conntrack-enabled forwarding test (retpoline thunk used). Signed-off-by: Florian Westphal

net: move the nat function to nf_nat_ovs for ovs and tc

2022-12-12T10:14:03+00:00

There are two nat functions are nearly the same in both OVS and TC code, (ovs_)ct_nat_execute() and ovs_ct_nat/tcf_ct_act_nat(). This patch creates nf_nat_ovs.c under netfilter and moves them there then exports nf_ct_nat() so that it can be shared by both OVS and TC, and keeps the nat (type) check and nat flag update in OVS and TC's own place, as these parts are different between OVS and TC. Note that in OVS nat function it was using skb->protocol to get the proto as it already skips vlans in key_extract(), while it doesn't in TC, and TC has to call skb_protocol() to get proto. So in nf_ct_nat_execute(), we keep using skb_protocol() which works for both OVS and TC contrack. Signed-off-by: Xin Long Acked-by: Aaron Conole Acked-by: Pablo Neira Ayuso Signed-off-by: David S. Miller

netfilter: nft_inner: support for inner tunnel header matching

2022-10-25T11:48:42+00:00

This new expression allows you to match on the inner headers that are encapsulated by any of the existing tunneling protocols. This expression parses the inner packet to set the link, network and transport offsets, so the existing expressions (with a few updates) can be reused to match on the inner headers. The inner expression supports for different tunnel combinations such as: - ethernet frame over IPv4/IPv6 packet, eg. VxLAN. - IPv4/IPv6 packet over IPv4/IPv6 packet, eg. IPIP. - IPv4/IPv6 packet over IPv4/IPv6 + transport header, eg. GRE. - transport header (ESP or SCTP) over transport header (usually UDP) The following fields are used to describe the tunnel protocol: - flags, which describe how to parse the inner headers: NFT_PAYLOAD_CTX_INNER_TUN, the tunnel provides its own header. NFT_PAYLOAD_CTX_INNER_ETHER, the ethernet frame is available as inner header. NFT_PAYLOAD_CTX_INNER_NH, the network header is available as inner header. NFT_PAYLOAD_CTX_INNER_TH, the transport header is available as inner header. For example, VxLAN sets on all of these flags. While GRE only sets on NFT_PAYLOAD_CTX_INNER_NH and NFT_PAYLOAD_CTX_INNER_TH. Then, ESP over UDP only sets on NFT_PAYLOAD_CTX_INNER_TH. The tunnel description is composed of the following attributes: - header size: in case the tunnel comes with its own header, eg. VxLAN. - type: this provides a hint to userspace on how to delinearize the rule. This is useful for VxLAN and Geneve since they run over UDP, since transport does not provide a hint. This is also useful in case hardware offload is ever supported. The type is not currently interpreted by the kernel. - expression: currently only payload supported. Follow up patch adds also inner meta support which is required by autogenerated dependencies. The exthdr expression should be supported too at some point. There is a new inner_ops operation that needs to be set on to allow to use an existing expression from the inner expression. This patch adds a new NFT_PAYLOAD_TUN_HEADER base which allows to match on the tunnel header fields, eg. vxlan vni. The payload expression is embedded into nft_inner private area and this private data area is passed to the payload inner eval function via direct call. Signed-off-by: Pablo Neira Ayuso

netfilter: nft_objref: make it builtin

2022-10-25T11:48:35+00:00

nft_objref is needed to reference named objects, it makes no sense to disable it. Before: text data bss dec filename 4014 424 0 4438 nft_objref.o 4174 1128 0 5302 nft_objref.ko 359351 15276 864 375491 nf_tables.ko After: text data bss dec filename 3815 408 0 4223 nft_objref.o 363161 15692 864 379717 nf_tables.ko Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

net: netfilter: move bpf_ct_set_nat_info kfunc in nf_nat_bpf.c

2022-10-03T16:17:32+00:00

Remove circular dependency between nf_nat module and nf_conntrack one moving bpf_ct_set_nat_info kfunc in nf_nat_bpf.c Fixes: 0fabd2aa199f ("net: netfilter: add bpf_ct_set_nat_info kfunc helper") Suggested-by: Kumar Kartikeya Dwivedi Tested-by: Nathan Chancellor Tested-by: Yauheni Kaliuta Signed-off-by: Lorenzo Bianconi Acked-by: John Fastabend Link: https://lore.kernel.org/r/51a65513d2cda3eeb0754842e8025ab3966068d8.1664490511.git.lorenzo@kernel.org Signed-off-by: Alexei Starovoitov

netfilter: nf_flow_table: count pending offload workqueue tasks

2022-07-11T14:25:14+00:00

To improve hardware offload debuggability count pending 'add', 'del' and 'stats' flow_table offload workqueue tasks. Counters are incremented before scheduling new task and decremented when workqueue handler finishes executing. These counters allow user to diagnose congestion on hardware offload workqueues that can happen when either CPU is starved and workqueue jobs are executed at lower rate than new ones are added or when hardware/driver can't keep up with the rate. Implement the described counters as percpu counters inside new struct netns_ft which is stored inside struct net. Expose them via new procfs file '/proc/net/stats/nf_flowtable' that is similar to existing 'nf_conntrack' file. Signed-off-by: Vlad Buslov Signed-off-by: Oz Shlomo Signed-off-by: Pablo Neira Ayuso

net/netfilter: Add unstable CT lookup helpers for XDP and TC-BPF

2022-01-18T22:26:42+00:00

This change adds conntrack lookup helpers using the unstable kfunc call interface for the XDP and TC-BPF hooks. The primary usecase is implementing a synproxy in XDP, see Maxim's patchset [0]. Export get_net_ns_by_id as nf_conntrack_bpf.c needs to call it. This object is only built when CONFIG_DEBUG_INFO_BTF_MODULES is enabled. [0]: https://lore.kernel.org/bpf/20211019144655.3483197-1-maximmi@nvidia.com Signed-off-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20220114163953.1455836-7-memxor@gmail.com Signed-off-by: Alexei Starovoitov

netfilter: nf_tables: make counter support built-in

2021-12-23T00:07:35+00:00

Make counter support built-in to allow for direct call in case of CONFIG_RETPOLINE. Signed-off-by: Pablo Neira Ayuso