From patchwork Wed Sep 4 10:48:20 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Mikhail Ivanov X-Patchwork-Id: 13790485 Received: from szxga04-in.huawei.com (szxga04-in.huawei.com [45.249.212.190]) (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 768501D220C; Wed, 4 Sep 2024 10:49:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.190 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725446943; cv=none; b=M+xVfTyDLg+xKRiRNlN5RVzWLjSDBQppXct8e8rcKrlL4h8DOH4LlWT1+xYinDAbt0scqBe09HxIk0sLXif4gIWdykemw1Jnxb6Gx7qLdKvgrx3Dm9kSePOlc7Ins4wnR2fLSbjvODOntDLOYzd1G0nTSJ2XqA0ACzbp5+ij1kc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725446943; c=relaxed/simple; bh=ZQhcZ7oABbdgp64nuh8UmhP5SCvaqs8uKBtCbxWMHX0=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=orXkfoKzg4sAH1xMO8d2FHeuVr9bgf2FVzcgH2HhnZFNCdXfRZ9JL3gJT3tRqz1sKKjq5aB/tnATAJjcqR7I347cSz2wdmU0bDgixW/FOmF3c9kyz+t6bbB7iUn8I0Nt3WR1cCpA7gVWDVYrQjm+6duIkC9Utll6zrlNmmBwoYw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei-partners.com; spf=pass smtp.mailfrom=huawei-partners.com; arc=none smtp.client-ip=45.249.212.190 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei-partners.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei-partners.com Received: from mail.maildlp.com (unknown [172.19.163.17]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4WzJyB1vspz20nLj; Wed, 4 Sep 2024 18:44:02 +0800 (CST) Received: from kwepemj200016.china.huawei.com (unknown [7.202.194.28]) by mail.maildlp.com (Postfix) with ESMTPS id 5375C1A0188; Wed, 4 Sep 2024 18:48:59 +0800 (CST) Received: from mscphis02103.huawei.com (10.123.65.215) by kwepemj200016.china.huawei.com (7.202.194.28) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Wed, 4 Sep 2024 18:48:57 +0800 From: Mikhail Ivanov To: CC: , , , , , , , Subject: [RFC PATCH v3 15/19] selftests/landlock: Test SCTP peeloff restriction Date: Wed, 4 Sep 2024 18:48:20 +0800 Message-ID: <20240904104824.1844082-16-ivanov.mikhail1@huawei-partners.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240904104824.1844082-1-ivanov.mikhail1@huawei-partners.com> References: <20240904104824.1844082-1-ivanov.mikhail1@huawei-partners.com> Precedence: bulk X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: mscpeml500004.china.huawei.com (7.188.26.250) To kwepemj200016.china.huawei.com (7.202.194.28) It is possible to branch off an SCTP UDP association into a separate user space UDP socket. Add test validating that such scenario is not restricted by Landlock. Move setup_loopback() helper from net_test to common.h to use it to enable connection in this test. Signed-off-by: Mikhail Ivanov Reviewed-by: Günther Noack --- tools/testing/selftests/landlock/common.h | 12 +++ tools/testing/selftests/landlock/net_test.c | 11 -- .../testing/selftests/landlock/socket_test.c | 102 +++++++++++++++++- 3 files changed, 113 insertions(+), 12 deletions(-) diff --git a/tools/testing/selftests/landlock/common.h b/tools/testing/selftests/landlock/common.h index 28df49fa22d5..07d959a8ac7b 100644 --- a/tools/testing/selftests/landlock/common.h +++ b/tools/testing/selftests/landlock/common.h @@ -16,6 +16,7 @@ #include #include #include +#include #include "../kselftest_harness.h" @@ -227,3 +228,14 @@ enforce_ruleset(struct __test_metadata *const _metadata, const int ruleset_fd) TH_LOG("Failed to enforce ruleset: %s", strerror(errno)); } } + +static void setup_loopback(struct __test_metadata *const _metadata) +{ + set_cap(_metadata, CAP_SYS_ADMIN); + ASSERT_EQ(0, unshare(CLONE_NEWNET)); + clear_cap(_metadata, CAP_SYS_ADMIN); + + set_ambient_cap(_metadata, CAP_NET_ADMIN); + ASSERT_EQ(0, system("ip link set dev lo up")); + clear_ambient_cap(_metadata, CAP_NET_ADMIN); +} diff --git a/tools/testing/selftests/landlock/net_test.c b/tools/testing/selftests/landlock/net_test.c index f21cfbbc3638..0b8386657c72 100644 --- a/tools/testing/selftests/landlock/net_test.c +++ b/tools/testing/selftests/landlock/net_test.c @@ -103,17 +103,6 @@ static int set_service(struct service_fixture *const srv, return 1; } -static void setup_loopback(struct __test_metadata *const _metadata) -{ - set_cap(_metadata, CAP_SYS_ADMIN); - ASSERT_EQ(0, unshare(CLONE_NEWNET)); - clear_cap(_metadata, CAP_SYS_ADMIN); - - set_ambient_cap(_metadata, CAP_NET_ADMIN); - ASSERT_EQ(0, system("ip link set dev lo up")); - clear_ambient_cap(_metadata, CAP_NET_ADMIN); -} - static bool is_restricted(const struct protocol_variant *const prot, const enum sandbox_type sandbox) { diff --git a/tools/testing/selftests/landlock/socket_test.c b/tools/testing/selftests/landlock/socket_test.c index 67db0e1c1121..2ab27196fa3d 100644 --- a/tools/testing/selftests/landlock/socket_test.c +++ b/tools/testing/selftests/landlock/socket_test.c @@ -11,8 +11,11 @@ #include #include #include -#include +#include +#include +#include #include +#include #include "common.h" @@ -839,4 +842,101 @@ TEST_F(socket_creation, socketpair) } } +static const char loopback_ipv4[] = "127.0.0.1"; +static const int backlog = 10; +static const int loopback_port = 1024; + +TEST_F(socket_creation, sctp_peeloff) +{ + int status, ret; + pid_t child; + struct sockaddr_in addr; + int server_fd; + + server_fd = + socket(AF_INET, SOCK_SEQPACKET | SOCK_CLOEXEC, IPPROTO_SCTP); + ASSERT_LE(0, server_fd); + + addr.sin_family = AF_INET; + addr.sin_port = htons(loopback_port); + addr.sin_addr.s_addr = inet_addr(loopback_ipv4); + + ASSERT_EQ(0, bind(server_fd, &addr, sizeof(addr))); + ASSERT_EQ(0, listen(server_fd, backlog)); + + child = fork(); + ASSERT_LE(0, child); + if (child == 0) { + int client_fd; + sctp_peeloff_flags_arg_t peeloff; + socklen_t peeloff_size = sizeof(peeloff); + const struct landlock_ruleset_attr ruleset_attr = { + .handled_access_socket = LANDLOCK_ACCESS_SOCKET_CREATE, + }; + struct landlock_socket_attr sctp_socket_create = { + .allowed_access = LANDLOCK_ACCESS_SOCKET_CREATE, + .family = AF_INET, + .type = SOCK_SEQPACKET, + }; + + /* Closes listening socket for the child. */ + ASSERT_EQ(0, close(server_fd)); + + client_fd = socket(AF_INET, SOCK_SEQPACKET | SOCK_CLOEXEC, + IPPROTO_SCTP); + ASSERT_LE(0, client_fd); + + /* + * Establishes connection between sockets and + * gets SCTP association id. + */ + ret = setsockopt(client_fd, IPPROTO_SCTP, SCTP_SOCKOPT_CONNECTX, + &addr, sizeof(addr)); + ASSERT_LE(0, ret); + + if (self->sandboxed) { + /* Denies creation of SCTP sockets. */ + int ruleset_fd = landlock_create_ruleset( + &ruleset_attr, sizeof(ruleset_attr), 0); + ASSERT_LE(0, ruleset_fd); + + if (self->allowed) { + ASSERT_EQ(0, landlock_add_rule( + ruleset_fd, + LANDLOCK_RULE_SOCKET, + &sctp_socket_create, 0)); + } + enforce_ruleset(_metadata, ruleset_fd); + ASSERT_EQ(0, close(ruleset_fd)); + } + /* + * Branches off current SCTP association into a separate socket + * and returns it to user space. + */ + peeloff.p_arg.associd = ret; + ret = getsockopt(client_fd, IPPROTO_SCTP, SCTP_SOCKOPT_PEELOFF, + &peeloff, &peeloff_size); + + /* + * Creation of SCTP socket by branching off existing SCTP association + * should not be restricted by Landlock. + */ + EXPECT_LE(0, ret); + + /* Closes peeloff socket if such was created. */ + if (!ret) { + ASSERT_EQ(0, close(peeloff.p_arg.sd)); + } + ASSERT_EQ(0, close(client_fd)); + _exit(_metadata->exit_code); + return; + } + + ASSERT_EQ(child, waitpid(child, &status, 0)); + ASSERT_EQ(1, WIFEXITED(status)); + ASSERT_EQ(EXIT_SUCCESS, WEXITSTATUS(status)); + + ASSERT_EQ(0, close(server_fd)); +} + TEST_HARNESS_MAIN