From patchwork Tue Jun 13 10:15:01 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lorenz Bauer X-Patchwork-Id: 13278270 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 227D6C7EE2E for ; Tue, 13 Jun 2023 10:15:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241712AbjFMKPQ (ORCPT ); Tue, 13 Jun 2023 06:15:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47780 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241390AbjFMKPM (ORCPT ); Tue, 13 Jun 2023 06:15:12 -0400 Received: from mail-wm1-x330.google.com (mail-wm1-x330.google.com [IPv6:2a00:1450:4864:20::330]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7E496188 for ; Tue, 13 Jun 2023 03:15:07 -0700 (PDT) Received: by mail-wm1-x330.google.com with SMTP id 5b1f17b1804b1-3f8c74af64fso4963955e9.1 for ; Tue, 13 Jun 2023 03:15:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=isovalent.com; s=google; t=1686651306; x=1689243306; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=Rrd+oVQwBiLqnLnpd+kxgQqY6NXFWO5dlCZVFiDqXJs=; b=dON+bTrbeu4YdnaPb/0E4JBD/k66UBlAuGkGgEM1IT4EBxyQgknhhh9qWXJFqGKRng iFcdbQRxNyZMN1tQ2IcfrV/PsxLrlIaEJIrVMMf48yVUKpC42+NOLlZSEmhhixGxfXwI CtNwVYiZarmA353WCs5heKR1GTec1S1Ki+HWhZp4OFrEjjJn2JNapjMuc5+UZ7VYewiA Wud9nvis58lr75DYbN/5v8sH5x2/DFiDusIW3coumC3DbR0USwALX3qaBX/Y9mnQUh4v tqNOl2/qQ+Oz2DHotIRdZ20HD6k4lXVsT3CTA4DTaqmVJdirpieNSR0Hn1EljbemKC+S i0KQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1686651306; x=1689243306; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Rrd+oVQwBiLqnLnpd+kxgQqY6NXFWO5dlCZVFiDqXJs=; b=Bt6UKHo3TK2THmhqrNnut2Q0MzMHth6OoiEy8h3bVn/iO3KXFCJY0xiguBoJQGZ49T K8iPSU8+XVxVlLl58aPiB3ye53GQ8NHYQ20gPhrtmINSeZdXAsXUMApGPcWivIVLy6L4 8h6o9uT+0KyimJMwmlAaBzxpFeqII1jGxf8eGF5Fqbkejhdb5pZ0kvQd2r32thHXzK1V fXm3K6aU4c4y7HwnWTqB+NV0MKEqfsT4zGk+dWhw0Sy6FnnhNHexcPNGZvqKR0ggf7ea miEcR+QI8vabCu+pBuVCs+KTE0BU12ip8oeBe+ajfXHZTejmQg9szmGN0TR9+PErDrce rtUg== X-Gm-Message-State: AC+VfDwZpvzCcoBCC61ok5CDWIh7y0rtz15zkMQ6aWIUCcxjvBHomhy5 iSUak+tdncuZxc3z80YzrU0AYQ== X-Google-Smtp-Source: ACHHUZ5GQ7sIG+N/DYtNauCCoD5it7RXk8FH3aWkE29SOtDbV2w/tlexjvz4Ac9XivlhyLXPHYycTw== X-Received: by 2002:a5d:55cf:0:b0:2f9:ee8c:a2fa with SMTP id i15-20020a5d55cf000000b002f9ee8ca2famr6402072wrw.64.1686651305914; Tue, 13 Jun 2023 03:15:05 -0700 (PDT) Received: from [192.168.133.193] ([5.148.46.226]) by smtp.gmail.com with ESMTPSA id k15-20020a5d6e8f000000b0030e6096afb6sm15075020wrz.12.2023.06.13.03.15.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 13 Jun 2023 03:15:05 -0700 (PDT) From: Lorenz Bauer Date: Tue, 13 Jun 2023 11:15:01 +0100 Subject: [PATCH bpf-next v2 6/6] selftests/bpf: Test that SO_REUSEPORT can be used with sk_assign helper MIME-Version: 1.0 Message-Id: <20230613-so-reuseport-v2-6-b7c69a342613@isovalent.com> References: <20230613-so-reuseport-v2-0-b7c69a342613@isovalent.com> In-Reply-To: <20230613-so-reuseport-v2-0-b7c69a342613@isovalent.com> To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , David Ahern , Willem de Bruijn , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Joe Stringer , Mykola Lysenko , Shuah Khan , Kuniyuki Iwashima Cc: Hemanth Malla , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, linux-kselftest@vger.kernel.org, Lorenz Bauer , Joe Stringer X-Mailer: b4 0.12.2 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org From: Daniel Borkmann We use two programs to check that the new reuseport logic is executed appropriately. The first is a TC clsact program which bpf_sk_assigns the skb to a UDP or TCP socket created by user space. Since the test communicates via lo we see both directions of packets in the eBPF. Traffic ingressing to the reuseport socket is identified by looking at the destination port. For TCP, we additionally need to make sure that we only assign the initial SYN packets towards our listening socket. The network stack then creates a request socket which transitions to ESTABLISHED after the 3WHS. The second is a reuseport program which shares the fact that it has been executed with user space. This tells us that the delayed lookup mechanism is working. Signed-off-by: Daniel Borkmann Co-developed-by: Lorenz Bauer Signed-off-by: Lorenz Bauer Cc: Joe Stringer --- tools/testing/selftests/bpf/network_helpers.c | 3 + .../selftests/bpf/prog_tests/assign_reuse.c | 197 +++++++++++++++++++++ .../selftests/bpf/progs/test_assign_reuse.c | 142 +++++++++++++++ 3 files changed, 342 insertions(+) diff --git a/tools/testing/selftests/bpf/network_helpers.c b/tools/testing/selftests/bpf/network_helpers.c index a105c0cd008a..8a33bcea97de 100644 --- a/tools/testing/selftests/bpf/network_helpers.c +++ b/tools/testing/selftests/bpf/network_helpers.c @@ -423,6 +423,9 @@ struct nstoken *open_netns(const char *name) void close_netns(struct nstoken *token) { + if (!token) + return; + ASSERT_OK(setns(token->orig_netns_fd, CLONE_NEWNET), "setns"); close(token->orig_netns_fd); free(token); diff --git a/tools/testing/selftests/bpf/prog_tests/assign_reuse.c b/tools/testing/selftests/bpf/prog_tests/assign_reuse.c new file mode 100644 index 000000000000..622f123410f4 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/assign_reuse.c @@ -0,0 +1,197 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Isovalent */ +#include +#include + +#include +#include + +#include "network_helpers.h" +#include "test_assign_reuse.skel.h" + +#define NS_TEST "assign_reuse" +#define LOOPBACK 1 +#define PORT 4443 + +static int attach_reuseport(int sock_fd, int prog_fd) +{ + return setsockopt(sock_fd, SOL_SOCKET, SO_ATTACH_REUSEPORT_EBPF, + &prog_fd, sizeof(prog_fd)); +} + +static __u64 cookie(int fd) +{ + __u64 cookie = 0; + socklen_t cookie_len = sizeof(cookie); + int ret; + + ret = getsockopt(fd, SOL_SOCKET, SO_COOKIE, &cookie, &cookie_len); + ASSERT_OK(ret, "cookie"); + ASSERT_GT(cookie, 0, "cookie_invalid"); + + return cookie; +} + +static int echo_test_udp(int fd_sv) +{ + struct sockaddr_storage addr = {}; + socklen_t len = sizeof(addr); + char buff[1] = {}; + int fd_cl = -1, ret; + + fd_cl = connect_to_fd(fd_sv, 100); + ASSERT_GT(fd_cl, 0, "create_client"); + ASSERT_EQ(getsockname(fd_cl, (void *)&addr, &len), 0, "getsockname"); + + ASSERT_EQ(send(fd_cl, buff, sizeof(buff), 0), 1, "send_client"); + + ret = recv(fd_sv, buff, sizeof(buff), 0); + if (ret < 0) + return errno; + + ASSERT_EQ(ret, 1, "recv_server"); + ASSERT_EQ(sendto(fd_sv, buff, sizeof(buff), 0, (void *)&addr, len), 1, "send_server"); + ASSERT_EQ(recv(fd_cl, buff, sizeof(buff), 0), 1, "recv_client"); + close(fd_cl); + return 0; +} + +static int echo_test_tcp(int fd_sv) +{ + char buff[1] = {}; + int fd_cl = -1, fd_sv_cl = -1; + + fd_cl = connect_to_fd(fd_sv, 100); + if (fd_cl < 0) + return errno; + + fd_sv_cl = accept(fd_sv, NULL, NULL); + ASSERT_GE(fd_sv_cl, 0, "accept_fd"); + + ASSERT_EQ(send(fd_cl, buff, sizeof(buff), 0), 1, "send_client"); + ASSERT_EQ(recv(fd_sv_cl, buff, sizeof(buff), 0), 1, "recv_server"); + ASSERT_EQ(send(fd_sv_cl, buff, sizeof(buff), 0), 1, "send_server"); + ASSERT_EQ(recv(fd_cl, buff, sizeof(buff), 0), 1, "recv_client"); + close(fd_sv_cl); + close(fd_cl); + return 0; +} + +void run_assign_reuse(int family, int sotype, const char *ip, __u16 port) +{ + DECLARE_LIBBPF_OPTS(bpf_tc_hook, tc_hook, + .ifindex = LOOPBACK, + .attach_point = BPF_TC_INGRESS, + ); + DECLARE_LIBBPF_OPTS(bpf_tc_opts, tc_opts, + .handle = 1, + .priority = 1, + ); + bool hook_created = false, tc_attached = false; + int ret, fd_tc, fd_accept, fd_drop, fd_map; + int *fd_sv = NULL; + __u64 fd_val; + struct test_assign_reuse *skel; + const int zero = 0; + + skel = test_assign_reuse__open(); + if (!ASSERT_OK_PTR(skel, "skel_open")) + goto cleanup; + + skel->rodata->dest_port = port; + + ret = test_assign_reuse__load(skel); + if (!ASSERT_OK(ret, "skel_load")) + goto cleanup; + + ASSERT_EQ(skel->bss->sk_cookie_seen, 0, "cookie_init"); + + fd_tc = bpf_program__fd(skel->progs.tc_main); + fd_accept = bpf_program__fd(skel->progs.reuse_accept); + fd_drop = bpf_program__fd(skel->progs.reuse_drop); + fd_map = bpf_map__fd(skel->maps.sk_map); + + fd_sv = start_reuseport_server(family, sotype, ip, port, 100, 1); + if (!ASSERT_NEQ(fd_sv, NULL, "start_reuseport_server")) + goto cleanup; + + ret = attach_reuseport(*fd_sv, fd_drop); + if (!ASSERT_OK(ret, "attach_reuseport")) + goto cleanup; + + fd_val = *fd_sv; + ret = bpf_map_update_elem(fd_map, &zero, &fd_val, BPF_NOEXIST); + if (!ASSERT_OK(ret, "bpf_sk_map")) + goto cleanup; + + ret = bpf_tc_hook_create(&tc_hook); + if (ret == 0) + hook_created = true; + ret = ret == -EEXIST ? 0 : ret; + if (!ASSERT_OK(ret, "bpf_tc_hook_create")) + goto cleanup; + + tc_opts.prog_fd = fd_tc; + ret = bpf_tc_attach(&tc_hook, &tc_opts); + if (!ASSERT_OK(ret, "bpf_tc_attach")) + goto cleanup; + tc_attached = true; + + if (sotype == SOCK_STREAM) + ASSERT_EQ(echo_test_tcp(*fd_sv), ECONNREFUSED, "drop_tcp"); + else + ASSERT_EQ(echo_test_udp(*fd_sv), EAGAIN, "drop_udp"); + ASSERT_EQ(skel->bss->reuseport_executed, 1, "program executed once"); + + skel->bss->sk_cookie_seen = 0; + skel->bss->reuseport_executed = 0; + ASSERT_OK(attach_reuseport(*fd_sv, fd_accept), "attach_reuseport(accept)"); + + if (sotype == SOCK_STREAM) + ASSERT_EQ(echo_test_tcp(*fd_sv), 0, "echo_tcp"); + else + ASSERT_EQ(echo_test_udp(*fd_sv), 0, "echo_udp"); + + ASSERT_EQ(skel->bss->sk_cookie_seen, cookie(*fd_sv), + "cookie_mismatch"); + ASSERT_EQ(skel->bss->reuseport_executed, 1, "program executed once"); +cleanup: + if (tc_attached) { + tc_opts.flags = tc_opts.prog_fd = tc_opts.prog_id = 0; + ret = bpf_tc_detach(&tc_hook, &tc_opts); + ASSERT_OK(ret, "bpf_tc_detach"); + } + if (hook_created) { + tc_hook.attach_point = BPF_TC_INGRESS | BPF_TC_EGRESS; + bpf_tc_hook_destroy(&tc_hook); + } + test_assign_reuse__destroy(skel); + free_fds(fd_sv, 1); +} + +void test_assign_reuse(void) +{ + struct nstoken *tok = NULL; + + SYS(out, "ip netns add %s", NS_TEST); + SYS(cleanup, "ip -net %s link set dev lo up", NS_TEST); + + tok = open_netns(NS_TEST); + if (!ASSERT_OK_PTR(tok, "netns token")) + return; + + if (test__start_subtest("tcpv4")) + run_assign_reuse(AF_INET, SOCK_STREAM, "127.0.0.1", PORT); + if (test__start_subtest("tcpv6")) + run_assign_reuse(AF_INET6, SOCK_STREAM, "::1", PORT); + if (test__start_subtest("udpv4")) + run_assign_reuse(AF_INET, SOCK_DGRAM, "127.0.0.1", PORT); + if (test__start_subtest("udpv6")) + run_assign_reuse(AF_INET6, SOCK_DGRAM, "::1", PORT); + +cleanup: + close_netns(tok); + SYS_NOFAIL("ip netns delete %s", NS_TEST); +out: + return; +} diff --git a/tools/testing/selftests/bpf/progs/test_assign_reuse.c b/tools/testing/selftests/bpf/progs/test_assign_reuse.c new file mode 100644 index 000000000000..4f2e2321ea06 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_assign_reuse.c @@ -0,0 +1,142 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Isovalent */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +char LICENSE[] SEC("license") = "GPL"; + +__u64 sk_cookie_seen; +__u64 reuseport_executed; +union { + struct tcphdr tcp; + struct udphdr udp; +} headers; + +const volatile __u16 dest_port; + +struct { + __uint(type, BPF_MAP_TYPE_SOCKMAP); + __uint(max_entries, 1); + __type(key, __u32); + __type(value, __u64); +} sk_map SEC(".maps"); + +SEC("sk_reuseport") +int reuse_accept(struct sk_reuseport_md *ctx) +{ + reuseport_executed++; + + if (ctx->ip_protocol == IPPROTO_TCP) { + if (ctx->data + sizeof(headers.tcp) > ctx->data_end) + return SK_DROP; + + if (__builtin_memcmp(&headers.tcp, ctx->data, sizeof(headers.tcp)) != 0) + return SK_DROP; + } else if (ctx->ip_protocol == IPPROTO_UDP) { + if (ctx->data + sizeof(headers.udp) > ctx->data_end) + return SK_DROP; + + if (__builtin_memcmp(&headers.udp, ctx->data, sizeof(headers.udp)) != 0) + return SK_DROP; + } else { + return SK_DROP; + } + + sk_cookie_seen = bpf_get_socket_cookie(ctx->sk); + return SK_PASS; +} + +SEC("sk_reuseport") +int reuse_drop(struct sk_reuseport_md *ctx) +{ + reuseport_executed++; + sk_cookie_seen = 0; + return SK_DROP; +} + +static int +assign_sk(struct __sk_buff *skb) +{ + int zero = 0, ret = 0; + struct bpf_sock *sk; + + sk = bpf_map_lookup_elem(&sk_map, &zero); + if (!sk) + return TC_ACT_SHOT; + ret = bpf_sk_assign(skb, sk, 0); + bpf_sk_release(sk); + return ret ? TC_ACT_SHOT : TC_ACT_OK; +} + +static bool +maybe_assign_tcp(struct __sk_buff *skb, struct tcphdr *th) +{ + if (th + 1 > (void *)(long)(skb->data_end)) + return TC_ACT_SHOT; + + if (!th->syn || th->ack || th->dest != bpf_htons(dest_port)) + return TC_ACT_OK; + + __builtin_memcpy(&headers.tcp, th, sizeof(headers.tcp)); + return assign_sk(skb); +} + +static bool +maybe_assign_udp(struct __sk_buff *skb, struct udphdr *uh) +{ + if (uh + 1 > (void *)(long)(skb->data_end)) + return TC_ACT_SHOT; + + if (uh->dest != bpf_htons(dest_port)) + return TC_ACT_OK; + + __builtin_memcpy(&headers.udp, uh, sizeof(headers.udp)); + return assign_sk(skb); +} + +SEC("tc") +int tc_main(struct __sk_buff *skb) +{ + void *data_end = (void *)(long)skb->data_end; + void *data = (void *)(long)skb->data; + struct ethhdr *eth; + + eth = (struct ethhdr *)(data); + if (eth + 1 > data_end) + return TC_ACT_SHOT; + + if (eth->h_proto == bpf_htons(ETH_P_IP)) { + struct iphdr *iph = (struct iphdr *)(data + sizeof(*eth)); + + if (iph + 1 > data_end) + return TC_ACT_SHOT; + + if (iph->protocol == IPPROTO_TCP) + return maybe_assign_tcp(skb, (struct tcphdr *)(iph + 1)); + else if (iph->protocol == IPPROTO_UDP) + return maybe_assign_udp(skb, (struct udphdr *)(iph + 1)); + else + return TC_ACT_SHOT; + } else { + struct ipv6hdr *ip6h = (struct ipv6hdr *)(data + sizeof(*eth)); + + if (ip6h + 1 > data_end) + return TC_ACT_SHOT; + + if (ip6h->nexthdr == IPPROTO_TCP) + return maybe_assign_tcp(skb, (struct tcphdr *)(ip6h + 1)); + else if (ip6h->nexthdr == IPPROTO_UDP) + return maybe_assign_udp(skb, (struct udphdr *)(ip6h + 1)); + else + return TC_ACT_SHOT; + } +}