From patchwork Thu May 23 12:06:17 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lorenzo Bianconi X-Patchwork-Id: 13671679 X-Patchwork-Delegate: bpf@iogearbox.net Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CC76C13C668; Thu, 23 May 2024 12:06:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716465997; cv=none; b=kwmR+uyJuJIcCZ6XgwBLq5H7PTCdpPbVuhYJ1s0YAr/T7kUAQZkpZKWyB1MZt/NUVoJeWJjibdG5hqz5lRJG26ezIteyRgJDO5yerhu7IxJ5S8zCM8yQBt2lwQjby3T7LbuahG2155+eIIF2aInoVt8H/orjyNfMrrrLKpMDIwI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716465997; c=relaxed/simple; bh=RuIIF8wNVzaT8qpCWyhTQmky4aY50mtLPhtH5sghHhw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=j8/ZjKNn4MPI7mIV82IdYyEhDapPgmZvFWfSQEX5tMAsUbjtQb1/8kZo43p6QQdkM/6kWMkf4ZSAflOcH+AkgnAO6s2U/Hcci6GUPn8Fom+f8QSTPXQv6v//MrztCnHnwNImJzFtTnXGpnap3bVAAcqtSfRKuIpoJHf3tvpvvx4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Isv4RAAe; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Isv4RAAe" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1E1B9C2BD10; Thu, 23 May 2024 12:06:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1716465997; bh=RuIIF8wNVzaT8qpCWyhTQmky4aY50mtLPhtH5sghHhw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Isv4RAAexUWCu/DJL6AhkS6/r7Kv0zLjRtgr/g5rovllQrlMctFqVvSKWSd0026/E NM3du5d9xSX7hfktn6Crq3VWFZjRO5bE7+xUn2KYzZrRpXeV+c7oI8e+nHEmQGTnrs qDKu6z3od1872LgBvfgcOAN23sFXcfEMyy1CX1FXC2eIjY43RmfwumlF4/Yo2o4+PM YiVZDpKhVcUGDMiZNVb52Vdfpzy5w9KiFKturW0l5vIpdkD//BPPoZSqUQ5F8b8N3t zhqqyPqvmZBG8RKilz6vYhb8HfzO7yIRg0aMko4t4DkFSenWRtv5DILKMP1MdMT3nb 7NpCIJLkHjzbw== From: Lorenzo Bianconi To: bpf@vger.kernel.org Cc: pablo@netfilter.org, kadlec@netfilter.org, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, netfilter-devel@vger.kernel.org, netdev@vger.kernel.org, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, martin.lau@linux.dev, eddyz87@gmail.com, lorenzo.bianconi@redhat.com, toke@redhat.com, fw@strlen.de, hawk@kernel.org, horms@kernel.org, donhunte@redhat.com, memxor@gmail.com Subject: [PATCH v3 bpf-next 2/3] netfilter: add bpf_xdp_flow_lookup kfunc Date: Thu, 23 May 2024 14:06:17 +0200 Message-ID: X-Mailer: git-send-email 2.45.1 In-Reply-To: References: Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: bpf@iogearbox.net Introduce bpf_xdp_flow_lookup kfunc in order to perform the lookup of a given flowtable entry based on a fib tuple of incoming traffic. bpf_xdp_flow_lookup can be used as building block to offload in xdp the processing of sw flowtable when hw flowtable is not available. Acked-by: Kumar Kartikeya Dwivedi Signed-off-by: Lorenzo Bianconi --- include/net/netfilter/nf_flow_table.h | 10 +++ net/netfilter/Makefile | 5 ++ net/netfilter/nf_flow_table_bpf.c | 117 ++++++++++++++++++++++++++ net/netfilter/nf_flow_table_inet.c | 2 +- 4 files changed, 133 insertions(+), 1 deletion(-) create mode 100644 net/netfilter/nf_flow_table_bpf.c diff --git a/include/net/netfilter/nf_flow_table.h b/include/net/netfilter/nf_flow_table.h index 0bbe6ea8e0651..fb4bfeb569dee 100644 --- a/include/net/netfilter/nf_flow_table.h +++ b/include/net/netfilter/nf_flow_table.h @@ -312,6 +312,16 @@ unsigned int nf_flow_offload_ip_hook(void *priv, struct sk_buff *skb, unsigned int nf_flow_offload_ipv6_hook(void *priv, struct sk_buff *skb, const struct nf_hook_state *state); +#if (IS_BUILTIN(CONFIG_NF_FLOW_TABLE) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF)) || \ + (IS_MODULE(CONFIG_NF_FLOW_TABLE) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF_MODULES)) +extern int nf_flow_register_bpf(void); +#else +static inline int nf_flow_register_bpf(void) +{ + return 0; +} +#endif + #define MODULE_ALIAS_NF_FLOWTABLE(family) \ MODULE_ALIAS("nf-flowtable-" __stringify(family)) diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile index 614815a3ed738..18b09cec92024 100644 --- a/net/netfilter/Makefile +++ b/net/netfilter/Makefile @@ -144,6 +144,11 @@ obj-$(CONFIG_NF_FLOW_TABLE) += nf_flow_table.o nf_flow_table-objs := nf_flow_table_core.o nf_flow_table_ip.o \ nf_flow_table_offload.o nf_flow_table-$(CONFIG_NF_FLOW_TABLE_PROCFS) += nf_flow_table_procfs.o +ifeq ($(CONFIG_NF_FLOW_TABLE),m) +nf_flow_table-$(CONFIG_DEBUG_INFO_BTF_MODULES) += nf_flow_table_bpf.o +else ifeq ($(CONFIG_NF_FLOW_TABLE),y) +nf_flow_table-$(CONFIG_DEBUG_INFO_BTF) += nf_flow_table_bpf.o +endif obj-$(CONFIG_NF_FLOW_TABLE_INET) += nf_flow_table_inet.o diff --git a/net/netfilter/nf_flow_table_bpf.c b/net/netfilter/nf_flow_table_bpf.c new file mode 100644 index 0000000000000..b3f8dffe62535 --- /dev/null +++ b/net/netfilter/nf_flow_table_bpf.c @@ -0,0 +1,117 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Unstable Flow Table Helpers for XDP hook + * + * These are called from the XDP programs. + * Note that it is allowed to break compatibility for these functions since + * the interface they are exposed through to BPF programs is explicitly + * unstable. + */ + +#include +#include +#include +#include +#include +#include +#include + +/* bpf_flowtable_opts - options for bpf flowtable helpers + * @error: out parameter, set for any encountered error + */ +struct bpf_flowtable_opts { + s32 error; +}; + +enum { + NF_BPF_FLOWTABLE_OPTS_SZ = 4, +}; + +__diag_push(); +__diag_ignore_all("-Wmissing-prototypes", + "Global functions as their definitions will be in nf_flow_table BTF"); + +static struct flow_offload_tuple_rhash * +bpf_xdp_flow_tuple_lookup(struct net_device *dev, + struct flow_offload_tuple *tuple, __be16 proto) +{ + struct flow_offload_tuple_rhash *tuplehash; + struct nf_flowtable *nf_flow_table; + struct flow_offload *nf_flow; + + nf_flow_table = nf_flowtable_by_dev(dev); + if (!nf_flow_table) + return ERR_PTR(-ENOENT); + + tuplehash = flow_offload_lookup(nf_flow_table, tuple); + if (!tuplehash) + return ERR_PTR(-ENOENT); + + nf_flow = container_of(tuplehash, struct flow_offload, + tuplehash[tuplehash->tuple.dir]); + flow_offload_refresh(nf_flow_table, nf_flow, false); + + return tuplehash; +} + +__bpf_kfunc struct flow_offload_tuple_rhash * +bpf_xdp_flow_lookup(struct xdp_md *ctx, struct bpf_fib_lookup *fib_tuple, + struct bpf_flowtable_opts *opts, u32 opts_len) +{ + struct xdp_buff *xdp = (struct xdp_buff *)ctx; + struct flow_offload_tuple tuple = { + .iifidx = fib_tuple->ifindex, + .l3proto = fib_tuple->family, + .l4proto = fib_tuple->l4_protocol, + .src_port = fib_tuple->sport, + .dst_port = fib_tuple->dport, + }; + struct flow_offload_tuple_rhash *tuplehash; + __be16 proto; + + if (opts_len != NF_BPF_FLOWTABLE_OPTS_SZ) { + opts->error = -EINVAL; + return NULL; + } + + switch (fib_tuple->family) { + case AF_INET: + tuple.src_v4.s_addr = fib_tuple->ipv4_src; + tuple.dst_v4.s_addr = fib_tuple->ipv4_dst; + proto = htons(ETH_P_IP); + break; + case AF_INET6: + tuple.src_v6 = *(struct in6_addr *)&fib_tuple->ipv6_src; + tuple.dst_v6 = *(struct in6_addr *)&fib_tuple->ipv6_dst; + proto = htons(ETH_P_IPV6); + break; + default: + opts->error = -EAFNOSUPPORT; + return NULL; + } + + tuplehash = bpf_xdp_flow_tuple_lookup(xdp->rxq->dev, &tuple, proto); + if (IS_ERR(tuplehash)) { + opts->error = PTR_ERR(tuplehash); + return NULL; + } + + return tuplehash; +} + +__diag_pop() + +BTF_KFUNCS_START(nf_ft_kfunc_set) +BTF_ID_FLAGS(func, bpf_xdp_flow_lookup, KF_TRUSTED_ARGS | KF_RET_NULL) +BTF_KFUNCS_END(nf_ft_kfunc_set) + +static const struct btf_kfunc_id_set nf_flow_kfunc_set = { + .owner = THIS_MODULE, + .set = &nf_ft_kfunc_set, +}; + +int nf_flow_register_bpf(void) +{ + return register_btf_kfunc_id_set(BPF_PROG_TYPE_XDP, + &nf_flow_kfunc_set); +} +EXPORT_SYMBOL_GPL(nf_flow_register_bpf); diff --git a/net/netfilter/nf_flow_table_inet.c b/net/netfilter/nf_flow_table_inet.c index 6eef15648b7b0..88787b45e30d6 100644 --- a/net/netfilter/nf_flow_table_inet.c +++ b/net/netfilter/nf_flow_table_inet.c @@ -98,7 +98,7 @@ static int __init nf_flow_inet_module_init(void) nft_register_flowtable_type(&flowtable_ipv6); nft_register_flowtable_type(&flowtable_inet); - return 0; + return nf_flow_register_bpf(); } static void __exit nf_flow_inet_module_exit(void)