From patchwork Tue Dec 7 16:22:49 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mathieu Jadin X-Patchwork-Id: 521786 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 7A4FFC433F5 for ; Tue, 7 Dec 2021 16:24:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234652AbhLGQ2N (ORCPT ); Tue, 7 Dec 2021 11:28:13 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44756 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230028AbhLGQ2M (ORCPT ); Tue, 7 Dec 2021 11:28:12 -0500 Received: from mail-ed1-x531.google.com (mail-ed1-x531.google.com [IPv6:2a00:1450:4864:20::531]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5EDA9C061574; Tue, 7 Dec 2021 08:24:41 -0800 (PST) Received: by mail-ed1-x531.google.com with SMTP id y13so58979347edd.13; Tue, 07 Dec 2021 08:24:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=cal9mgrfJeOC1t+KTZvLGazz6Vso8H/zFO8jZhM8iBo=; b=iE8IO3izriODdoUDlr44Meea61jxwybW6kVWqJKv30Nn85ei3+I8pXMc9cqh0TnTOg UTqvL0zToFLtUX0kdrR77H6GsCC6Q9IhEDV3TAzVeA3MTWDcL+5SInvnOtmi0CDE/ZFJ RK5r+Xmu8m+2SG/d+pZlFAhTICKLvkHDXL/6jbA5Q/4SyGYwITDnpmfp754j2t8mwsnw 8c1x+kNHCPzkKt8dFD+LstcrEk3K4MyA/7Ett9r5P0WM/TU4pPnGT2zYLzPFke2o/QLf Cry3ildvBhV6FQ0mNSJbXEItmzM6SnbQpRl+dXkjzs9hFWsycRXqqMmAXD8ac+CDXWdz vloQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=cal9mgrfJeOC1t+KTZvLGazz6Vso8H/zFO8jZhM8iBo=; b=VjXHRBnP8DwAi4YlsGg16dGDC7U7Q8ZlXwUZJdIeIESBqLWeFcgw0D9wDpu3ouMH2B Ny1CRyaXzHUZzxP4EFxciCPsWrdbZRCjeMJWU0oGfVXDk8i0efR5ALJQzLj7I72ok1CO sc6wkvoWwilfjAjnqpx1Rt5v0S2I7jPvz2XqvGvmYyP8HhFA5vB9ApJYnIQdYniUcVW+ jZCgyjj/Bvufv1qJpzQ1lDNDOtldDCJdnYFNVx+En6kMKF/HCQroCi0Wd1ne1FhaABo3 jHkNwe06Jy+ctLgLEuUUTuaXW9QybZSxL6gp9KbQ7b5uqNdY9IpuixMBSg3J/08tck6X ce8Q== X-Gm-Message-State: AOAM532WjUTDvywUjR1tLJLd/XQE7ZOCOZ/yx0cgDuS/dT8a7u/PPxt0 ErSsXwnNkdMF+lac29KE9FxlWE1TpNChOQ== X-Google-Smtp-Source: ABdhPJxGZv56emhF1h6iMskn586AJ1Ae3K5o4Gl1fXpY3V5CvC+z3YrX4ofK6tXdhZyRxkcxjIf/Qw== X-Received: by 2002:a05:6402:3cd:: with SMTP id t13mr10602633edw.97.1638894279805; Tue, 07 Dec 2021 08:24:39 -0800 (PST) Received: from localhost.localdomain ([2a02:a03f:c062:a800:5f01:482d:95e2:b968]) by smtp.gmail.com with ESMTPSA id i10sm6757ejw.48.2021.12.07.08.24.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 07 Dec 2021 08:24:39 -0800 (PST) From: Mathieu Jadin To: bpf@vger.kernel.org Cc: Mathieu Jadin , John Fastabend , Yonghong Song , linux-kselftest@vger.kernel.org, Martin KaFai Lau , netdev@vger.kernel.org, Shuah Khan , KP Singh , Daniel Borkmann , Alexei Starovoitov , Song Liu , Andrii Nakryiko Subject: [PATCH bpf-next 2/2] selftests/bpf: Test for IPv6 ext header parsing Date: Tue, 7 Dec 2021 17:22:49 +0100 Message-Id: <20211207162249.301625-2-mathjadin@gmail.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20211207162249.301625-1-mathjadin@gmail.com> References: <20211207162249.301625-1-mathjadin@gmail.com> MIME-Version: 1.0 X-Developer-Signature: v=1; a=ed25519-sha256; t=1638884270; l=7638; s=20211207; h=from:subject; bh=S9PpPGXrudTAXfgr3NRpH/1lgYiOVeZ/V9FOjs3vHDg=; b=bkjqSaNcM0gc6wbUMv+UdtJrBX5uE4NWu7v7wJq7tjZtOgJw1gjhH7HlsREREQ5cbOiZwsRzBpWX QCN4MRa8DMBiKX1KTjmAsd/skYxFiT19SRS6wwZqxPSpuoDGw6Xt X-Developer-Key: i=mathjadin@gmail.com; a=ed25519; pk=LX0wKHMKZralQziQacrPu4w5BceQsC7CocWV714TPRU= Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org This test creates a client and a server exchanging a single byte with a Segment Routing Header and the eBPF program saves the inner segment in a sk_storage. The test program checks that the segment is correct. Signed-off-by: Mathieu Jadin --- .../bpf/prog_tests/tcp_ipv6_exthdr_srh.c | 171 ++++++++++++++++++ .../selftests/bpf/progs/tcp_ipv6_exthdr_srh.c | 78 ++++++++ 2 files changed, 249 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/tcp_ipv6_exthdr_srh.c create mode 100644 tools/testing/selftests/bpf/progs/tcp_ipv6_exthdr_srh.c diff --git a/tools/testing/selftests/bpf/prog_tests/tcp_ipv6_exthdr_srh.c b/tools/testing/selftests/bpf/prog_tests/tcp_ipv6_exthdr_srh.c new file mode 100644 index 000000000000..70f7ee230975 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/tcp_ipv6_exthdr_srh.c @@ -0,0 +1,171 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include "cgroup_helpers.h" +#include "network_helpers.h" + +struct tcp_srh_storage { + struct in6_addr inner_segment; +}; + +static void send_byte(int fd) +{ + char b = 0x55; + + if (CHECK_FAIL(send(fd, &b, sizeof(b), 0) != 1)) + perror("Failed to send single byte"); +} + +static int verify_srh(int map_fd, int server_fd, struct ipv6_sr_hdr *client_srh) +{ + int err = 0; + struct tcp_srh_storage val; + + if (CHECK_FAIL(bpf_map_lookup_elem(map_fd, &server_fd, &val) < 0)) { + perror("Failed to read socket storage"); + return -1; + } + + if (memcmp(&val.inner_segment, &client_srh->segments[1], + sizeof(struct in6_addr))) { + log_err("The inner segment of the received SRH differs from the sent one"); + err++; + } + + return err; +} + +static int run_test(int cgroup_fd, int listen_fd) +{ + struct bpf_prog_load_attr attr = { + .prog_type = BPF_PROG_TYPE_SOCK_OPS, + .file = "./tcp_ipv6_exthdr_srh.o", + .expected_attach_type = BPF_CGROUP_SOCK_OPS, + }; + size_t srh_size = sizeof(struct ipv6_sr_hdr) + + 2 * sizeof(struct in6_addr); + struct ipv6_sr_hdr *client_srh; + struct bpf_object *obj; + struct bpf_map *map; + struct timeval tv; + int client_fd; + int server_fd; + int prog_fd; + int map_fd; + char byte; + int err; + + err = bpf_prog_load_xattr(&attr, &obj, &prog_fd); + if (err) { + log_err("Failed to load BPF object"); + return -1; + } + + map = bpf_object__next_map(obj, NULL); + map_fd = bpf_map__fd(map); + + err = bpf_prog_attach(prog_fd, cgroup_fd, BPF_CGROUP_SOCK_OPS, 0); + if (err) { + log_err("Failed to attach BPF program"); + goto close_bpf_object; + } + + client_fd = connect_to_fd(listen_fd, 0); + if (client_fd < 0) { + err = -1; + goto close_bpf_object; + } + + server_fd = accept(listen_fd, NULL, 0); + if (server_fd < 0) { + err = -1; + goto close_client_fd; + } + + /* Set an SRH with ::1 as an intermediate segment on the client */ + + client_srh = calloc(1, srh_size); + if (!client_srh) { + log_err("Failed to create the SRH to send"); + goto close_server_fd; + } + client_srh->type = IPV6_SRCRT_TYPE_4; + // We do not count the first 8 bytes (RFC 8200 Section 4.4) + client_srh->hdrlen = (2 * sizeof(struct in6_addr)) >> 3; + client_srh->segments_left = 1; + client_srh->first_segment = 1; + // client_srh->segments[0] is set by the kernel + memcpy(&client_srh->segments[1], &in6addr_loopback, + sizeof(struct in6_addr)); + + if (setsockopt(client_fd, SOL_IPV6, IPV6_RTHDR, client_srh, + srh_size)) { + log_err("Failed to set the SRH on the client"); + goto free_srh; + } + + /* Send traffic with this SRH + * and check its parsing on the server side + */ + + tv.tv_sec = 1; + tv.tv_usec = 0; + if (setsockopt(server_fd, SOL_SOCKET, SO_RCVTIMEO, (const char *)&tv, + sizeof(tv))) { + log_err("Failed to set the receive timeout on the server"); + err = -1; + goto free_srh; + } + + send_byte(client_fd); + if (recv(server_fd, &byte, 1, 0) != 1) { + log_err("Failed to get the byte under one second on the server 2"); + err = -1; + goto free_srh; + } + + err += verify_srh(map_fd, server_fd, client_srh); + +free_srh: + free(client_srh); +close_server_fd: + close(server_fd); +close_client_fd: + close(client_fd); +close_bpf_object: + bpf_object__close(obj); + return err; +} + +void test_tcp_ipv6_exthdr_srh(void) +{ + int server_fd, cgroup_fd; + + cgroup_fd = test__join_cgroup("/tcp_ipv6_exthdr_srh"); + if (CHECK_FAIL(cgroup_fd < 0)) + return; + + server_fd = start_server(AF_INET6, SOCK_STREAM, "::1", 0, 0); + if (CHECK_FAIL(server_fd < 0)) + goto close_cgroup_fd; + + if (CHECK_FAIL(system("sysctl net.ipv6.conf.all.seg6_enabled=1"))) + goto close_server; + + if (CHECK_FAIL(system("sysctl net.ipv6.conf.lo.seg6_enabled=1"))) + goto reset_sysctl; + + CHECK_FAIL(run_test(cgroup_fd, server_fd)); + + if (CHECK_FAIL(system("sysctl net.ipv6.conf.lo.seg6_enabled=0"))) + log_err("Cannot reset sysctl net.ipv6.conf.lo.seg6_enabled to 0"); + +reset_sysctl: + if (CHECK_FAIL(system("sysctl net.ipv6.conf.all.seg6_enabled=0"))) + log_err("Cannot reset sysctl net.ipv6.conf.all.seg6_enabled to 0"); + +close_server: + close(server_fd); +close_cgroup_fd: + close(cgroup_fd); +} diff --git a/tools/testing/selftests/bpf/progs/tcp_ipv6_exthdr_srh.c b/tools/testing/selftests/bpf/progs/tcp_ipv6_exthdr_srh.c new file mode 100644 index 000000000000..276bda8bbecb --- /dev/null +++ b/tools/testing/selftests/bpf/progs/tcp_ipv6_exthdr_srh.c @@ -0,0 +1,78 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include +#include + +char _license[] SEC("license") = "GPL"; + +#define NEXTHDR_ROUTING 43 + +struct tcp_srh_storage { + struct in6_addr inner_segment; +}; + +struct { + __uint(type, BPF_MAP_TYPE_SK_STORAGE); + __uint(map_flags, BPF_F_NO_PREALLOC); + __type(key, int); + __type(value, struct tcp_srh_storage); +} socket_storage_map SEC(".maps"); + +/* Check the header received from the active side */ +static int read_incoming_srh(struct bpf_sock_ops *skops, + struct tcp_srh_storage *storage) +{ + __u32 seg_size = 2 * sizeof(struct in6_addr); + struct ipv6_sr_hdr *srh; + struct ipv6hdr *ip6; + void *seg_list; + int ret = 1; + + ip6 = (struct ipv6hdr *)skops->skb_data; + if (ip6 + 1 <= skops->skb_data_end && ip6->nexthdr == NEXTHDR_ROUTING) { + srh = (struct ipv6_sr_hdr *)(ip6 + 1); + if (srh + 1 <= skops->skb_data_end) { + if (srh->type != IPV6_SRCRT_TYPE_4) + return ret; + + seg_list = (void *)(srh + 1); + if (seg_list + seg_size <= skops->skb_data_end) { + // This is an SRH with at least 2 segments + storage->inner_segment = srh->segments[1]; + ret = 0; + } + } + } + + return ret; +} + +SEC("sockops") +int srh_read(struct bpf_sock_ops *skops) +{ + struct tcp_srh_storage *storage; + int true_val = 1; + + if (!skops->sk) + return 1; + + storage = bpf_sk_storage_get(&socket_storage_map, skops->sk, 0, + BPF_SK_STORAGE_GET_F_CREATE); + if (!storage) + return 1; + + switch (skops->op) { + case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB: + case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB: + bpf_sock_ops_cb_flags_set(skops, skops->bpf_sock_ops_cb_flags | + BPF_SOCK_OPS_PARSE_IPV6_HDR_CB_FLAG); + break; + case BPF_SOCK_OPS_PARSE_IPV6_HDR_CB: + return read_incoming_srh(skops, storage); + } + + return 0; +}