From patchwork Wed May 15 21:12:56 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lorenzo Bianconi X-Patchwork-Id: 13665553 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 66DDE2F877; Wed, 15 May 2024 21:13:18 +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=1715807598; cv=none; b=d+cuTpwZAkzaTkgPQLRKG5vR3st0G92ebxpzVqrx2EbIwA0mTPhoiOuXkk/f8/us1Jor/TUptRTFV1T3I2fb12noHP01ll7QeGhb9rcwBRtM2uxq/a6vM9LgSA3OYqcGf75y+Op0Q28yFbz2Hovvlg1WhVfUts8r8KxYb1IuWn8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715807598; c=relaxed/simple; bh=v0uuuhUE2wqCSiEzBC0tUksx8Sxag17ovvMsswnSdSo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Sx6LWxSvpHk/JajAm/gIEnMcmcjuX7yZ//D7qgqea3BJcCDgJYHPJ5BKtBBMjeXFxgOS6xsbiiJ+nod80iSBdiBOJUZ7jQZVI33/DSTQGMAxB+7b7pbD3hKjdr1fJvDS8FBjdQgvzh4fzj7DhFhewIytWuOXIqGHa08L9rbfnNY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=joB91BFx; 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="joB91BFx" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 80174C32781; Wed, 15 May 2024 21:13:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1715807598; bh=v0uuuhUE2wqCSiEzBC0tUksx8Sxag17ovvMsswnSdSo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=joB91BFxiMP9Jdu3z/sDcsMVqpLfFKaBwDujTnjFetWBSv42uk0liEPpxwPVstaz2 iOVN3jxmjV7EhV0ch3STjP2UmRMeMfdBVlmAxkTBIdZbMbB1c+f5f8w5/gMTtvgLkZ +nCPbZZjUiEGe6WQ+IkmLMEi7+Xj4disYCYUn6TS3S1mRGE4+Mx3ze18SGdQQmxVKj aP/1kV2vMEJn6pIU1tRDmlliPyO5UBnpaRiacpTvQvx5OYUTK2Ma/95U4TRVbJefu5 +a4KT4QX89zPiUNwL+KnUCLIww+TbvCizrWa4JghXFSKl41c14kYLdOcqJdNp75Jln bkCQA2Dc8qqAA== 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, lorenzo.bianconi@redhat.com, toke@redhat.com, fw@strlen.de, hawk@kernel.org, horms@kernel.org, donhunte@redhat.com Subject: [PATCH bpf-next 3/4] samples/bpf: Add bpf sample to offload flowtable traffic to xdp Date: Wed, 15 May 2024 23:12:56 +0200 Message-ID: <2ce25de74134e96dfa0b21a419e7c01f31c41226.1715807303.git.lorenzo@kernel.org> X-Mailer: git-send-email 2.45.0 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 xdp_flowtable_offload bpf sample to offload sw flowtable logic in xdp layer if hw flowtable is not available or does not support a specific kind of traffic. Signed-off-by: Lorenzo Bianconi --- samples/bpf/Makefile | 7 +- samples/bpf/xdp_flowtable_offload.bpf.c | 592 +++++++++++++++++++++++ samples/bpf/xdp_flowtable_offload_user.c | 128 +++++ 3 files changed, 726 insertions(+), 1 deletion(-) create mode 100644 samples/bpf/xdp_flowtable_offload.bpf.c create mode 100644 samples/bpf/xdp_flowtable_offload_user.c diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile index 9aa027b144df6..a3d089ca224d5 100644 --- a/samples/bpf/Makefile +++ b/samples/bpf/Makefile @@ -46,6 +46,7 @@ tprogs-y += xdp_fwd tprogs-y += task_fd_query tprogs-y += ibumad tprogs-y += hbm +tprogs-y += xdp_flowtable_offload # Libbpf dependencies LIBBPF_SRC = $(TOOLS_PATH)/lib/bpf @@ -98,6 +99,7 @@ ibumad-objs := ibumad_user.o hbm-objs := hbm.o $(CGROUP_HELPERS) xdp_router_ipv4-objs := xdp_router_ipv4_user.o $(XDP_SAMPLE) +xdp_flowtable_offload-objs := xdp_flowtable_offload_user.o $(XDP_SAMPLE) # Tell kbuild to always build the programs always-y := $(tprogs-y) @@ -306,6 +308,7 @@ $(obj)/$(TRACE_HELPERS) $(obj)/$(CGROUP_HELPERS) $(obj)/$(XDP_SAMPLE): | libbpf_ .PHONY: libbpf_hdrs $(obj)/xdp_router_ipv4_user.o: $(obj)/xdp_router_ipv4.skel.h +$(obj)/xdp_flowtable_offload_user.o: $(obj)/xdp_flowtable_offload.skel.h $(obj)/tracex5.bpf.o: $(obj)/syscall_nrs.h $(obj)/hbm_out_kern.o: $(src)/hbm.h $(src)/hbm_kern.h @@ -361,6 +364,7 @@ endef CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG)) $(obj)/xdp_router_ipv4.bpf.o: $(obj)/xdp_sample.bpf.o +$(obj)/xdp_flowtable_offload.bpf.o: $(obj)/xdp_sample.bpf.o $(obj)/%.bpf.o: $(src)/%.bpf.c $(obj)/vmlinux.h $(src)/xdp_sample.bpf.h $(src)/xdp_sample_shared.h @echo " CLANG-BPF " $@ @@ -370,10 +374,11 @@ $(obj)/%.bpf.o: $(src)/%.bpf.c $(obj)/vmlinux.h $(src)/xdp_sample.bpf.h $(src)/x -I$(LIBBPF_INCLUDE) $(CLANG_SYS_INCLUDES) \ -c $(filter %.bpf.c,$^) -o $@ -LINKED_SKELS := xdp_router_ipv4.skel.h +LINKED_SKELS := xdp_router_ipv4.skel.h xdp_flowtable_offload.skel.h clean-files += $(LINKED_SKELS) xdp_router_ipv4.skel.h-deps := xdp_router_ipv4.bpf.o xdp_sample.bpf.o +xdp_flowtable_offload.skel.h-deps := xdp_flowtable_offload.bpf.o xdp_sample.bpf.o LINKED_BPF_SRCS := $(patsubst %.bpf.o,%.bpf.c,$(foreach skel,$(LINKED_SKELS),$($(skel)-deps))) diff --git a/samples/bpf/xdp_flowtable_offload.bpf.c b/samples/bpf/xdp_flowtable_offload.bpf.c new file mode 100644 index 0000000000000..728c859feefae --- /dev/null +++ b/samples/bpf/xdp_flowtable_offload.bpf.c @@ -0,0 +1,592 @@ +/* Copyright (c) 2024 Lorenzo Bianconi + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + */ + +#include "vmlinux.h" +#include "xdp_sample.bpf.h" +#include "xdp_sample_shared.h" + +#define MAX_ERRNO 4095 +#define IS_ERR_VALUE(x) (unsigned long)(void *)(x) >= (unsigned long)-MAX_ERRNO +#define BIT(x) (1 << (x)) + +#define ETH_P_IP 0x0800 +#define IP_MF 0x2000 /* "More Fragments" */ +#define IP_OFFSET 0x1fff /* "Fragment Offset" */ + +#define IPV6_FLOWINFO_MASK __cpu_to_be32(0x0fffffff) + +#define CSUM_MANGLED_0 ((__sum16)0xffff) + +struct flow_offload_tuple_rhash * +bpf_xdp_flow_offload_lookup(struct xdp_md *, + struct bpf_fib_lookup *, u32) __ksym; + +/* IP checksum utility routines */ + +static __always_inline __u32 csum_add(__u32 csum, __u32 addend) +{ + __u32 res = csum + addend; + + return res + (res < addend); +} + +static __always_inline __u16 csum_fold(__u32 csum) +{ + csum = (csum & 0xffff) + (csum >> 16); + csum = (csum & 0xffff) + (csum >> 16); + return ~csum; +} + +static __always_inline __u16 csum_replace4(__u32 csum, __u32 from, __u32 to) +{ + __u32 tmp = csum_add(~csum, ~from); + + return csum_fold(csum_add(tmp, to)); +} + +static __always_inline __u16 csum_replace16(__u32 csum, __u32 *from, __u32 *to) +{ + __u32 diff[] = { + ~from[0], ~from[1], ~from[2], ~from[3], + to[0], to[1], to[2], to[3], + }; + + csum = bpf_csum_diff(0, 0, diff, sizeof(diff), ~csum); + return csum_fold(csum); +} + +/* IP-TCP header utility routines */ + +static __always_inline void ip_decrease_ttl(struct iphdr *iph) +{ + __u32 check = (__u32)iph->check; + + check += (__u32)bpf_htons(0x0100); + iph->check = (__sum16)(check + (check >= 0xffff)); + iph->ttl--; +} + +static __always_inline bool +xdp_flowtable_offload_check_iphdr(struct iphdr *iph) +{ + /* ip fragmented traffic */ + if (iph->frag_off & bpf_htons(IP_MF | IP_OFFSET)) + return false; + + /* ip options */ + if (iph->ihl * 4 != sizeof(*iph)) + return false; + + if (iph->ttl <= 1) + return false; + + return true; +} + +static __always_inline bool +xdp_flowtable_offload_check_tcp_state(void *ports, void *data_end, u8 proto) +{ + if (proto == IPPROTO_TCP) { + struct tcphdr *tcph = ports; + + if (tcph + 1 > data_end) + return false; + + if (tcph->fin || tcph->rst) + return false; + } + + return true; +} + +/* IP nat utility routines */ + +static __always_inline void +xdp_flowtable_offload_nat_port(struct flow_ports *ports, void *data_end, + u8 proto, __be16 port, __be16 nat_port) +{ + switch (proto) { + case IPPROTO_TCP: { + struct tcphdr *tcph = (struct tcphdr *)ports; + + if (tcph + 1 > data_end) + break; + + tcph->check = csum_replace4((__u32)tcph->check, (__u32)port, + (__u32)nat_port); + break; + } + case IPPROTO_UDP: { + struct udphdr *udph = (struct udphdr *)ports; + + if (udph + 1 > data_end) + break; + + if (!udph->check) + break; + + udph->check = csum_replace4((__u32)udph->check, (__u32)port, + (__u32)nat_port); + if (!udph->check) + udph->check = CSUM_MANGLED_0; + break; + } + default: + break; + } +} + +static __always_inline void +xdp_flowtable_offload_snat_port(const struct flow_offload *flow, + struct flow_ports *ports, void *data_end, + u8 proto, enum flow_offload_tuple_dir dir) +{ + __be16 port, nat_port; + + if (ports + 1 > data_end) + return; + + switch (dir) { + case FLOW_OFFLOAD_DIR_ORIGINAL: + port = ports->source; + bpf_core_read(&nat_port, bpf_core_type_size(nat_port), + &flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.dst_port); + ports->source = nat_port; + break; + case FLOW_OFFLOAD_DIR_REPLY: + port = ports->dest; + bpf_core_read(&nat_port, bpf_core_type_size(nat_port), + &flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.src_port); + ports->dest = nat_port; + break; + default: + return; + } + + xdp_flowtable_offload_nat_port(ports, data_end, proto, port, nat_port); +} + +static __always_inline void +xdp_flowtable_offload_dnat_port(const struct flow_offload *flow, + struct flow_ports *ports, void *data_end, + u8 proto, enum flow_offload_tuple_dir dir) +{ + __be16 port, nat_port; + + if (ports + 1 > data_end) + return; + + switch (dir) { + case FLOW_OFFLOAD_DIR_ORIGINAL: + port = ports->dest; + bpf_core_read(&nat_port, bpf_core_type_size(nat_port), + &flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.src_port); + ports->dest = nat_port; + break; + case FLOW_OFFLOAD_DIR_REPLY: + port = ports->source; + bpf_core_read(&nat_port, bpf_core_type_size(nat_port), + &flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.dst_port); + ports->source = nat_port; + break; + default: + return; + } + + xdp_flowtable_offload_nat_port(ports, data_end, proto, port, nat_port); +} + +static __always_inline void +xdp_flowtable_offload_ip_l4(struct iphdr *iph, void *data_end, + __be32 addr, __be32 nat_addr) +{ + switch (iph->protocol) { + case IPPROTO_TCP: { + struct tcphdr *tcph = (struct tcphdr *)(iph + 1); + + if (tcph + 1 > data_end) + break; + + tcph->check = csum_replace4((__u32)tcph->check, addr, + nat_addr); + break; + } + case IPPROTO_UDP: { + struct udphdr *udph = (struct udphdr *)(iph + 1); + + if (udph + 1 > data_end) + break; + + if (!udph->check) + break; + + udph->check = csum_replace4((__u32)udph->check, addr, + nat_addr); + if (!udph->check) + udph->check = CSUM_MANGLED_0; + break; + } + default: + break; + } +} + +static __always_inline void +xdp_flowtable_offload_snat_ip(const struct flow_offload *flow, + struct iphdr *iph, void *data_end, + enum flow_offload_tuple_dir dir) +{ + __be32 addr, nat_addr; + + switch (dir) { + case FLOW_OFFLOAD_DIR_ORIGINAL: + addr = iph->saddr; + bpf_core_read(&nat_addr, bpf_core_type_size(nat_addr), + &flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.dst_v4.s_addr); + iph->saddr = nat_addr; + break; + case FLOW_OFFLOAD_DIR_REPLY: + addr = iph->daddr; + bpf_core_read(&nat_addr, bpf_core_type_size(nat_addr), + &flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.src_v4.s_addr); + iph->daddr = nat_addr; + break; + default: + return; + } + iph->check = csum_replace4((__u32)iph->check, addr, nat_addr); + + xdp_flowtable_offload_ip_l4(iph, data_end, addr, nat_addr); +} + +static __always_inline void +xdp_flowtable_offload_get_dnat_ip(const struct flow_offload *flow, + enum flow_offload_tuple_dir dir, + __be32 *addr) +{ + switch (dir) { + case FLOW_OFFLOAD_DIR_ORIGINAL: + bpf_core_read(addr, sizeof(*addr), + &flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.src_v4.s_addr); + break; + case FLOW_OFFLOAD_DIR_REPLY: + bpf_core_read(addr, sizeof(*addr), + &flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.dst_v4.s_addr); + break; + } +} + +static __always_inline void +xdp_flowtable_offload_dnat_ip(const struct flow_offload *flow, + struct iphdr *iph, void *data_end, + enum flow_offload_tuple_dir dir) +{ + __be32 addr, nat_addr; + + switch (dir) { + case FLOW_OFFLOAD_DIR_ORIGINAL: + addr = iph->daddr; + bpf_core_read(&nat_addr, bpf_core_type_size(nat_addr), + &flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.src_v4.s_addr); + iph->daddr = nat_addr; + break; + case FLOW_OFFLOAD_DIR_REPLY: + addr = iph->saddr; + bpf_core_read(&nat_addr, bpf_core_type_size(nat_addr), + &flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.dst_v4.s_addr); + iph->saddr = nat_addr; + break; + default: + return; + } + iph->check = csum_replace4((__u32)iph->check, addr, nat_addr); + + xdp_flowtable_offload_ip_l4(iph, data_end, addr, nat_addr); +} + +static __always_inline void +xdp_flowtable_offload_ipv6_l4(struct ipv6hdr *ip6h, void *data_end, + struct in6_addr *addr, struct in6_addr *nat_addr) +{ + switch (ip6h->nexthdr) { + case IPPROTO_TCP: { + struct tcphdr *tcph = (struct tcphdr *)(ip6h + 1); + + if (tcph + 1 > data_end) + break; + + tcph->check = csum_replace16((__u32)tcph->check, + addr->in6_u.u6_addr32, + nat_addr->in6_u.u6_addr32); + break; + } + case IPPROTO_UDP: { + struct udphdr *udph = (struct udphdr *)(ip6h + 1); + + if (udph + 1 > data_end) + break; + + if (!udph->check) + break; + + udph->check = csum_replace16((__u32)udph->check, + addr->in6_u.u6_addr32, + nat_addr->in6_u.u6_addr32); + if (!udph->check) + udph->check = CSUM_MANGLED_0; + break; + } + default: + break; + } +} + +static __always_inline void +xdp_flowtable_offload_snat_ipv6(const struct flow_offload *flow, + struct ipv6hdr *ip6h, void *data_end, + enum flow_offload_tuple_dir dir) +{ + struct in6_addr addr, nat_addr; + + switch (dir) { + case FLOW_OFFLOAD_DIR_ORIGINAL: + addr = ip6h->saddr; + bpf_core_read(&nat_addr, bpf_core_type_size(nat_addr), + &flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.dst_v6); + ip6h->saddr = nat_addr; + break; + case FLOW_OFFLOAD_DIR_REPLY: + addr = ip6h->daddr; + bpf_core_read(&nat_addr, bpf_core_type_size(nat_addr), + &flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.src_v6); + ip6h->daddr = nat_addr; + break; + default: + return; + } + + xdp_flowtable_offload_ipv6_l4(ip6h, data_end, &addr, &nat_addr); +} + +static __always_inline void +xdp_flowtable_offload_get_dnat_ipv6(const struct flow_offload *flow, + enum flow_offload_tuple_dir dir, + struct in6_addr *addr) +{ + switch (dir) { + case FLOW_OFFLOAD_DIR_ORIGINAL: + bpf_core_read(addr, sizeof(*addr), + &flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.src_v6); + break; + case FLOW_OFFLOAD_DIR_REPLY: + bpf_core_read(addr, sizeof(*addr), + &flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.dst_v6); + break; + } +} + +static __always_inline void +xdp_flowtable_offload_dnat_ipv6(const struct flow_offload *flow, + struct ipv6hdr *ip6h, void *data_end, + enum flow_offload_tuple_dir dir) +{ + struct in6_addr addr, nat_addr; + + switch (dir) { + case FLOW_OFFLOAD_DIR_ORIGINAL: + addr = ip6h->daddr; + bpf_core_read(&nat_addr, bpf_core_type_size(nat_addr), + &flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.src_v6); + ip6h->daddr = nat_addr; + break; + case FLOW_OFFLOAD_DIR_REPLY: + addr = ip6h->saddr; + bpf_core_read(&nat_addr, bpf_core_type_size(nat_addr), + &flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.dst_v6); + ip6h->saddr = nat_addr; + break; + default: + return; + } + + xdp_flowtable_offload_ipv6_l4(ip6h, data_end, &addr, &nat_addr); +} + +static __always_inline void +xdp_flowtable_offload_forward_ip(const struct flow_offload *flow, + void *data, void *data_end, + struct flow_ports *ports, + enum flow_offload_tuple_dir dir, + unsigned long flags) +{ + struct iphdr *iph = data + sizeof(struct ethhdr); + + if (iph + 1 > data_end) + return; + + if (flags & BIT(NF_FLOW_SNAT)) { + xdp_flowtable_offload_snat_port(flow, ports, data_end, + iph->protocol, dir); + xdp_flowtable_offload_snat_ip(flow, iph, data_end, dir); + } + if (flags & BIT(NF_FLOW_DNAT)) { + xdp_flowtable_offload_dnat_port(flow, ports, data_end, + iph->protocol, dir); + xdp_flowtable_offload_dnat_ip(flow, iph, data_end, dir); + } + + ip_decrease_ttl(iph); +} + +static __always_inline void +xdp_flowtable_offload_forward_ipv6(const struct flow_offload *flow, + void *data, void *data_end, + struct flow_ports *ports, + enum flow_offload_tuple_dir dir, + unsigned long flags) +{ + struct ipv6hdr *ip6h = data + sizeof(struct ethhdr); + + if (ip6h + 1 > data_end) + return; + + if (flags & BIT(NF_FLOW_SNAT)) { + xdp_flowtable_offload_snat_port(flow, ports, data_end, + ip6h->nexthdr, dir); + xdp_flowtable_offload_snat_ipv6(flow, ip6h, data_end, dir); + } + if (flags & BIT(NF_FLOW_DNAT)) { + xdp_flowtable_offload_dnat_port(flow, ports, data_end, + ip6h->nexthdr, dir); + xdp_flowtable_offload_dnat_ipv6(flow, ip6h, data_end, dir); + } + + ip6h->hop_limit--; +} + +SEC("xdp") +int xdp_flowtable_offload(struct xdp_md *ctx) +{ + void *data_end = (void *)(long)ctx->data_end; + struct flow_offload_tuple_rhash *tuplehash; + struct bpf_fib_lookup tuple = { + .ifindex = ctx->ingress_ifindex, + }; + void *data = (void *)(long)ctx->data; + enum flow_offload_tuple_dir dir; + struct ethhdr *eth = data; + struct flow_offload *flow; + struct flow_ports *ports; + unsigned long flags; + int iifindex; + + if (eth + 1 > data_end) + return XDP_PASS; + + switch (eth->h_proto) { + case bpf_htons(ETH_P_IP): { + struct iphdr *iph = data + sizeof(*eth); + + ports = (struct flow_ports *)(iph + 1); + if (ports + 1 > data_end) + return XDP_PASS; + + /* sanity check on ip header */ + if (!xdp_flowtable_offload_check_iphdr(iph)) + return XDP_PASS; + + if (!xdp_flowtable_offload_check_tcp_state(ports, data_end, + iph->protocol)) + return XDP_PASS; + + tuple.family = AF_INET; + tuple.tos = iph->tos; + tuple.l4_protocol = iph->protocol; + tuple.tot_len = bpf_ntohs(iph->tot_len); + tuple.ipv4_src = iph->saddr; + tuple.ipv4_dst = iph->daddr; + tuple.sport = ports->source; + tuple.dport = ports->dest; + break; + } + case bpf_htons(ETH_P_IPV6): { + struct in6_addr *src = (struct in6_addr *)tuple.ipv6_src; + struct in6_addr *dst = (struct in6_addr *)tuple.ipv6_dst; + struct ipv6hdr *ip6h = data + sizeof(*eth); + + ports = (struct flow_ports *)(ip6h + 1); + if (ports + 1 > data_end) + return XDP_PASS; + + if (ip6h->hop_limit <= 1) + return XDP_PASS; + + if (!xdp_flowtable_offload_check_tcp_state(ports, data_end, + ip6h->nexthdr)) + return XDP_PASS; + + tuple.family = AF_INET6; + tuple.l4_protocol = ip6h->nexthdr; + tuple.tot_len = bpf_ntohs(ip6h->payload_len); + *src = ip6h->saddr; + *dst = ip6h->daddr; + tuple.sport = ports->source; + tuple.dport = ports->dest; + break; + } + default: + return XDP_PASS; + } + + tuplehash = bpf_xdp_flow_offload_lookup(ctx, &tuple, sizeof(tuple)); + if (IS_ERR_VALUE(tuplehash)) + return XDP_PASS; + + dir = tuplehash->tuple.dir; + flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]); + if (bpf_core_read(&flags, sizeof(flags), &flow->flags)) + return XDP_PASS; + + switch (tuplehash->tuple.xmit_type) { + case FLOW_OFFLOAD_XMIT_NEIGH: + /* update the destination address in case of dnatting before + * performing the route lookup + */ + if (tuple.family == AF_INET6) + xdp_flowtable_offload_get_dnat_ipv6(flow, dir, + (struct in6_addr *)&tuple.ipv6_dst); + else + xdp_flowtable_offload_get_dnat_ip(flow, dir, &tuple.ipv4_src); + + if (bpf_fib_lookup(ctx, &tuple, sizeof(tuple), 0)) + return XDP_PASS; + + if (tuple.family == AF_INET6) + xdp_flowtable_offload_forward_ipv6(flow, data, data_end, + ports, dir, flags); + else + xdp_flowtable_offload_forward_ip(flow, data, data_end, + ports, dir, flags); + + __builtin_memcpy(eth->h_dest, tuple.dmac, ETH_ALEN); + __builtin_memcpy(eth->h_source, tuple.smac, ETH_ALEN); + iifindex = tuple.ifindex; + break; + case FLOW_OFFLOAD_XMIT_DIRECT: + default: + return XDP_PASS; + } + + return bpf_redirect(iifindex, 0); +} + +char _license[] SEC("license") = "GPL"; diff --git a/samples/bpf/xdp_flowtable_offload_user.c b/samples/bpf/xdp_flowtable_offload_user.c new file mode 100644 index 0000000000000..179b1f34b48fd --- /dev/null +++ b/samples/bpf/xdp_flowtable_offload_user.c @@ -0,0 +1,128 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (c) 2024 Lorenzo Bianconi + */ +static const char *__doc__ = +"XDP flowtable integration example\n" +"Usage: xdp_flowtable_offload \n"; + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "bpf_util.h" +#include "xdp_sample_user.h" +#include "xdp_flowtable_offload.skel.h" + +static int mask = SAMPLE_RX_CNT | SAMPLE_EXCEPTION_CNT; + +DEFINE_SAMPLE_INIT(xdp_flowtable_offload); + +static const struct option long_options[] = { + { "help", no_argument, NULL, 'h' }, + { "generic", no_argument, NULL, 'g' }, + {} +}; + +int main(int argc, char **argv) +{ + struct xdp_flowtable_offload *skel; + int ret = EXIT_FAIL_OPTION; + char ifname[IF_NAMESIZE]; + bool generic = false; + int ifindex; + int opt; + + while ((opt = getopt_long(argc, argv, "hg", + long_options, NULL)) != -1) { + switch (opt) { + case 'g': + generic = true; + break; + case 'h': + default: + sample_usage(argv, long_options, __doc__, mask, false); + return ret; + } + } + + if (argc <= optind) { + sample_usage(argv, long_options, __doc__, mask, true); + goto end; + } + + ifindex = if_nametoindex(argv[optind]); + if (!ifindex) + ifindex = strtoul(argv[optind], NULL, 0); + + if (!ifindex) { + fprintf(stderr, "Bad interface index or name\n"); + sample_usage(argv, long_options, __doc__, mask, true); + goto end; + } + + skel = xdp_flowtable_offload__open(); + if (!skel) { + fprintf(stderr, "Failed to xdp_flowtable_offload__open: %s\n", + strerror(errno)); + ret = EXIT_FAIL_BPF; + goto end; + } + + ret = sample_init_pre_load(skel); + if (ret < 0) { + fprintf(stderr, "Failed to sample_init_pre_load: %s\n", strerror(-ret)); + ret = EXIT_FAIL_BPF; + goto end_destroy; + } + + ret = xdp_flowtable_offload__load(skel); + if (ret < 0) { + fprintf(stderr, "Failed to xdp_flowtable_offload__load: %s\n", + strerror(errno)); + ret = EXIT_FAIL_BPF; + goto end_destroy; + } + + ret = sample_init(skel, mask); + if (ret < 0) { + fprintf(stderr, "Failed to initialize sample: %s\n", strerror(-ret)); + ret = EXIT_FAIL; + goto end_destroy; + } + + if (sample_install_xdp(skel->progs.xdp_flowtable_offload, + ifindex, generic, false) < 0) { + ret = EXIT_FAIL_XDP; + goto end_destroy; + } + + ret = EXIT_FAIL; + if (!if_indextoname(ifindex, ifname)) { + fprintf(stderr, "Failed to if_indextoname for %d: %s\n", ifindex, + strerror(errno)); + goto end_destroy; + } + + ret = sample_run(2, NULL, NULL); + if (ret < 0) { + fprintf(stderr, "Failed during sample run: %s\n", strerror(-ret)); + ret = EXIT_FAIL; + goto end_destroy; + } + ret = EXIT_OK; +end_destroy: + xdp_flowtable_offload__destroy(skel); +end: + sample_exit(ret); +}