From patchwork Tue Sep 6 23:48:48 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: YiFei Zhu X-Patchwork-Id: 12968295 X-Patchwork-Delegate: bpf@iogearbox.net 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 AC6E7C6FA83 for ; Tue, 6 Sep 2022 23:49:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229776AbiIFXtU (ORCPT ); Tue, 6 Sep 2022 19:49:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57680 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229687AbiIFXtK (ORCPT ); Tue, 6 Sep 2022 19:49:10 -0400 Received: from mail-pg1-x54a.google.com (mail-pg1-x54a.google.com [IPv6:2607:f8b0:4864:20::54a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EEC2D923E0 for ; Tue, 6 Sep 2022 16:49:08 -0700 (PDT) Received: by mail-pg1-x54a.google.com with SMTP id m188-20020a633fc5000000b00434dccacd4aso596072pga.10 for ; Tue, 06 Sep 2022 16:49:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date; bh=Cr4XROECByEa8+H/8TE3CUjlmvWQzQWyMK5Hotidfy8=; b=mLz3eXBkZ1XuKzuEFA1hCQ1f9P++LD+lzmRhH4LjBYOSNqZH08XdV+X/y9fKZTVOkW dK4CPoomGdobv8SUd8sEwb7QJ6iZyLVyAHTLOc8MW3SJB+pSKxzWgJ1aCy6HRmeX77OG AgX27x/0Q6GyyfJU6PbC+csskMiMnuUiGjSm2IPa0LGRffZDArGUoXpIW7JAr9zvRyUr i5TG0Q6CV5P1OqZb0+7Lc9lpr848YiWF3rkh5DLSXJMVjjzz4b7R2lXbEa45Wcq2VekV nqr0xFzjDENsp8D6PwY3El+vcQk+64o+Z1WFg2atB+l63eNVYJuC6+3/M8PZwEzVLn0T pFtw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date; bh=Cr4XROECByEa8+H/8TE3CUjlmvWQzQWyMK5Hotidfy8=; b=3Av4u5syodlYXfCfGGy8oOp5sSlS51sZZsmPiRhaYM0cENgQ5q/MH60VJrG1PIPA4I o2uXQ0K+jsy5MrDoQGaULruqTWgsmpqJrTvj+tf802MB+yIbD0tVs3zoxOS3hIAuNmi6 MduwaFnueNgOcpuMLdaJNjskidRNZONP8oGCBLZXZtKOteZFoAbcAPSVRlud80m9it1+ oNpSeQkBKWP9NN2fTgg4/0GUJ//kW7Vdvw2zvzpkvnq7Er5wrDjU5gz8twCK6ECJaEu9 GcrfHK7ZAa3TI8hmtSJbCFDcAp72FruMTpJA8E+EcMLqrSnKkJ/E1GhoChggOdmWSmWA 31Uw== X-Gm-Message-State: ACgBeo3Z2voKBNG0XKSNUeVV4atxPpxJY7POQgCnmlgmkjXxax98tDK8 ni5udEvxbjb5BWxOFhUQBk8Bxh2j5iyQww== X-Google-Smtp-Source: AA6agR6k+WcO2e+K5KgqMFMpr8a2NQZ00auHeE1XstkBhADMtNbphhQB0G1jNVuH5N4Ls/Nlgp2QINA/qspwWg== X-Received: from zhuyifei-kvm.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:2edc]) (user=zhuyifei job=sendgmr) by 2002:a17:90a:318f:b0:1fa:a374:f565 with SMTP id j15-20020a17090a318f00b001faa374f565mr27493354pjb.146.1662508148387; Tue, 06 Sep 2022 16:49:08 -0700 (PDT) Date: Tue, 6 Sep 2022 23:48:48 +0000 In-Reply-To: Mime-Version: 1.0 References: X-Mailer: git-send-email 2.37.2.789.g6183377224-goog Message-ID: <892e0898c1255f980da13b0c7cc77cd5642edd36.1662507638.git.zhuyifei@google.com> Subject: [PATCH v2 bpf-next 3/3] selftests/bpf: Ensure cgroup/connect{4,6} programs can bind unpriv ICMP ping From: YiFei Zhu To: bpf@vger.kernel.org Cc: netdev@vger.kernel.org, Alexei Starovoitov , Daniel Borkmann , Stanislav Fomichev , Martin KaFai Lau , John Fastabend , Jiri Olsa , "David S. Miller" , Hideaki YOSHIFUJI , David Ahern , Eric Dumazet , Jakub Kicinski , Paolo Abeni Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net This tests that when an unprivileged ICMP ping socket connects, the hooks are actually invoked. We also ensure that if the hook does not call bpf_bind(), the bound address is unmodified, and if the hook calls bpf_bind(), the bound address is exactly what we provided to the helper. A new netns is used to enable ping_group_range in the test without affecting ouside of the test, because by default, not even root is permitted to use unprivileged ICMP ping... Signed-off-by: YiFei Zhu --- .../selftests/bpf/prog_tests/connect_ping.c | 177 ++++++++++++++++++ .../selftests/bpf/progs/connect_ping.c | 53 ++++++ 2 files changed, 230 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/connect_ping.c create mode 100644 tools/testing/selftests/bpf/progs/connect_ping.c diff --git a/tools/testing/selftests/bpf/prog_tests/connect_ping.c b/tools/testing/selftests/bpf/prog_tests/connect_ping.c new file mode 100644 index 0000000000000..ba0812a06854e --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/connect_ping.c @@ -0,0 +1,177 @@ +// SPDX-License-Identifier: GPL-2.0-only + +/* + * Copyright 2022 Google LLC. + */ + +#define _GNU_SOURCE +#include + +#include "test_progs.h" +#include "cgroup_helpers.h" +#include "network_helpers.h" + +#include "connect_ping.skel.h" + +/* 2001:db8::1 */ +#define BINDADDR_V6 { { { 0x20,0x01,0x0d,0xb8,0,0,0,0,0,0,0,0,0,0,0,1 } } } +static const struct in6_addr bindaddr_v6 = BINDADDR_V6; + +static void subtest(int cgroup_fd, struct connect_ping *obj, + int family, int do_bind) +{ + struct sockaddr_in sa4 = { + .sin_family = AF_INET, + .sin_addr.s_addr = htonl(INADDR_LOOPBACK), + }; + struct sockaddr_in6 sa6 = { + .sin6_family = AF_INET6, + .sin6_addr = IN6ADDR_LOOPBACK_INIT, + }; + struct sockaddr *sa; + socklen_t sa_len; + int protocol; + int sock_fd; + + switch (family) { + case AF_INET: + sa = (struct sockaddr *)&sa4; + sa_len = sizeof(sa4); + protocol = IPPROTO_ICMP; + break; + case AF_INET6: + sa = (struct sockaddr *)&sa6; + sa_len = sizeof(sa6); + protocol = IPPROTO_ICMPV6; + break; + } + + memset(obj->bss, 0, sizeof(*obj->bss)); + obj->bss->do_bind = do_bind; + + sock_fd = socket(family, SOCK_DGRAM, protocol); + if (!ASSERT_GE(sock_fd, 0, "sock-create")) + return; + + if (!ASSERT_OK(connect(sock_fd, sa, sa_len), "connect")) + goto close_sock; + + if (!ASSERT_EQ(obj->bss->invocations_v4, family == AF_INET ? 1 : 0, + "invocations_v4")) + goto close_sock; + if (!ASSERT_EQ(obj->bss->invocations_v6, family == AF_INET6 ? 1 : 0, + "invocations_v6")) + goto close_sock; + if (!ASSERT_EQ(obj->bss->has_error, 0, "has_error")) + goto close_sock; + + if (!ASSERT_OK(getsockname(sock_fd, sa, &sa_len), + "getsockname")) + goto close_sock; + + switch (family) { + case AF_INET: + if (!ASSERT_EQ(sa4.sin_family, family, "sin_family")) + goto close_sock; + if (!ASSERT_EQ(sa4.sin_addr.s_addr, + htonl(do_bind ? 0x01010101 : INADDR_LOOPBACK), + "sin_addr")) + goto close_sock; + break; + case AF_INET6: + if (!ASSERT_EQ(sa6.sin6_family, AF_INET6, "sin6_family")) + goto close_sock; + if (!ASSERT_EQ(memcmp(&sa6.sin6_addr, + do_bind ? &bindaddr_v6 : &in6addr_loopback, + sizeof(sa6.sin6_addr)), + 0, "sin6_addr")) + goto close_sock; + break; + } + +close_sock: + close(sock_fd); +} + +void test_connect_ping(void) +{ + struct connect_ping *obj; + int cgroup_fd; + + if (!ASSERT_OK(unshare(CLONE_NEWNET | CLONE_NEWNS), "unshare")) + return; + + /* overmount sysfs, and making original sysfs private so overmount + * does not propagate to other mntns. + */ + if (!ASSERT_OK(mount("none", "/sys", NULL, MS_PRIVATE, NULL), + "remount-private-sys")) + return; + if (!ASSERT_OK(mount("sysfs", "/sys", "sysfs", 0, NULL), + "mount-sys")) + return; + if (!ASSERT_OK(mount("bpffs", "/sys/fs/bpf", "bpf", 0, NULL), + "mount-bpf")) + goto clean_mount; + + if (!ASSERT_OK(system("ip link set dev lo up"), "lo-up")) + goto clean_mount; + if (!ASSERT_OK(system("ip addr add 1.1.1.1 dev lo"), "lo-addr-v4")) + goto clean_mount; + if (!ASSERT_OK(system("ip -6 addr add 2001:db8::1 dev lo"), "lo-addr-v6")) + goto clean_mount; + if (write_sysctl("/proc/sys/net/ipv4/ping_group_range", "0 0")) + goto clean_mount; + + cgroup_fd = test__join_cgroup("/connect_ping"); + if (!ASSERT_GE(cgroup_fd, 0, "cg-create")) + goto clean_mount; + + obj = connect_ping__open_and_load(); + if (!ASSERT_OK_PTR(obj, "skel-load")) + goto close_cgroup; + obj->links.connect_v4_prog = + bpf_program__attach_cgroup(obj->progs.connect_v4_prog, cgroup_fd); + if (!ASSERT_OK_PTR(obj->links.connect_v4_prog, "cg-attach-v4")) + goto close_cgroup; + obj->links.connect_v6_prog = + bpf_program__attach_cgroup(obj->progs.connect_v6_prog, cgroup_fd); + if (!ASSERT_OK_PTR(obj->links.connect_v6_prog, "cg-attach-v6")) + goto close_cgroup; + + /* Connect a v4 ping socket to localhost, assert that only v4 is called, + * and called exactly once, and that the socket's bound address is + * original loopback address. + */ + if (test__start_subtest("ipv4")) + subtest(cgroup_fd, obj, AF_INET, 0); + + /* Connect a v4 ping socket to localhost, assert that only v4 is called, + * and called exactly once, and that the socket's bound address is + * address we explicitly bound. + */ + if (test__start_subtest("ipv4-bind")) + subtest(cgroup_fd, obj, AF_INET, 1); + + /* Connect a v6 ping socket to localhost, assert that only v6 is called, + * and called exactly once, and that the socket's bound address is + * original loopback address. + */ + if (test__start_subtest("ipv6")) + subtest(cgroup_fd, obj, AF_INET6, 0); + + /* Connect a v6 ping socket to localhost, assert that only v6 is called, + * and called exactly once, and that the socket's bound address is + * address we explicitly bound. + */ + if (test__start_subtest("ipv6-bind")) + subtest(cgroup_fd, obj, AF_INET6, 1); + + connect_ping__destroy(obj); + +close_cgroup: + close(cgroup_fd); + +clean_mount: + umount2("/sys", MNT_DETACH); +} diff --git a/tools/testing/selftests/bpf/progs/connect_ping.c b/tools/testing/selftests/bpf/progs/connect_ping.c new file mode 100644 index 0000000000000..60178192b672f --- /dev/null +++ b/tools/testing/selftests/bpf/progs/connect_ping.c @@ -0,0 +1,53 @@ +// SPDX-License-Identifier: GPL-2.0-only + +/* + * Copyright 2022 Google LLC. + */ + +#include +#include +#include +#include +#include + +/* 2001:db8::1 */ +#define BINDADDR_V6 { { { 0x20,0x01,0x0d,0xb8,0,0,0,0,0,0,0,0,0,0,0,1 } } } + +__u32 do_bind = 0; +__u32 has_error = 0; +__u32 invocations_v4 = 0; +__u32 invocations_v6 = 0; + +SEC("cgroup/connect4") +int connect_v4_prog(struct bpf_sock_addr *ctx) +{ + struct sockaddr_in sa = { + .sin_family = AF_INET, + .sin_addr.s_addr = bpf_htonl(0x01010101), + }; + + __sync_fetch_and_add(&invocations_v4, 1); + + if (do_bind && bpf_bind(ctx, (struct sockaddr *)&sa, sizeof(sa))) + has_error = 1; + + return 1; +} + +SEC("cgroup/connect6") +int connect_v6_prog(struct bpf_sock_addr *ctx) +{ + struct sockaddr_in6 sa = { + .sin6_family = AF_INET6, + .sin6_addr = BINDADDR_V6, + }; + + __sync_fetch_and_add(&invocations_v6, 1); + + if (do_bind && bpf_bind(ctx, (struct sockaddr *)&sa, sizeof(sa))) + has_error = 1; + + return 1; +} + +char _license[] SEC("license") = "GPL";