[PATCH v10 3/6] selftests/Landlock: Abstract UNIX socket restriction tests
Tahera Fahimi
fahimitahera at gmail.com
Tue Aug 20 04:08:53 UTC 2024
The patch introduces Landlock ABI version 6 and adds three types of tests
that examines different scenarios for abstract unix socket:
1) unix_socket: base tests of the abstract socket scoping mechanism for a
landlocked process, same as the ptrace test.
2) optional_scoping: generates three processes with different domains and
tests if a process with a non-scoped domain can connect to other
processes.
3) outside_socket: since the socket's creator credentials are used
for scoping sockets, this test examines the cases where the socket's
credentials are different from the process using it.
Signed-off-by: Tahera Fahimi <fahimitahera at gmail.com>
---
Changes in versions:
v10:
- Code improvements by changing fixture variables to local ones.
- Rename "unix_sock_special_cases" to "outside_socket"
v9:
- Move pathname_address_sockets to a different patch.
- Extend optional_scoping test scenarios.
- Removing hardcoded numbers and using "backlog" instead.
V8:
- Move tests to scoped_abstract_unix_test.c file.
- To avoid potential conflicts among Unix socket names in different tests,
set_unix_address is added to common.h to set different sun_path for Unix sockets.
- protocol_variant and service_fixture structures are also moved to common.h
- Adding pathname_address_sockets to cover all types of address formats
for unix sockets, and moving remove_path() to common.h to reuse in this test.
V7:
- Introducing landlock ABI version 6.
- Adding some edge test cases to optional_scoping test.
- Using `enum` for different domains in optional_scoping tests.
- Extend unix_sock_special_cases test cases for connected(SOCK_STREAM) sockets.
- Modifying inline comments.
V6:
- Introducing optional_scoping test which ensures a sandboxed process with a
non-scoped domain can still connect to another abstract unix socket(either
sandboxed or non-sandboxed).
- Introducing unix_sock_special_cases test which tests examines scenarios where
the connecting sockets have different domain than the process using them.
V4:
- Introducing unix_socket to evaluate the basic scoping mechanism for abstract
unix sockets.
---
tools/testing/selftests/landlock/common.h | 38 +
tools/testing/selftests/landlock/net_test.c | 31 +-
.../landlock/scoped_abstract_unix_test.c | 931 ++++++++++++++++++
3 files changed, 970 insertions(+), 30 deletions(-)
create mode 100644 tools/testing/selftests/landlock/scoped_abstract_unix_test.c
diff --git a/tools/testing/selftests/landlock/common.h b/tools/testing/selftests/landlock/common.h
index 7e2b431b9f90..cca387df86c2 100644
--- a/tools/testing/selftests/landlock/common.h
+++ b/tools/testing/selftests/landlock/common.h
@@ -7,6 +7,7 @@
* Copyright © 2021 Microsoft Corporation
*/
+#include <arpa/inet.h>
#include <errno.h>
#include <linux/landlock.h>
#include <linux/securebits.h>
@@ -14,10 +15,12 @@
#include <sys/socket.h>
#include <sys/syscall.h>
#include <sys/types.h>
+#include <sys/un.h>
#include <sys/wait.h>
#include <unistd.h>
#include "../kselftest_harness.h"
+#define TMP_DIR "tmp"
#ifndef __maybe_unused
#define __maybe_unused __attribute__((__unused__))
@@ -226,3 +229,38 @@ enforce_ruleset(struct __test_metadata *const _metadata, const int ruleset_fd)
TH_LOG("Failed to enforce ruleset: %s", strerror(errno));
}
}
+
+struct protocol_variant {
+ int domain;
+ int type;
+};
+
+struct service_fixture {
+ struct protocol_variant protocol;
+ /* port is also stored in ipv4_addr.sin_port or ipv6_addr.sin6_port */
+ unsigned short port;
+ union {
+ struct sockaddr_in ipv4_addr;
+ struct sockaddr_in6 ipv6_addr;
+ struct {
+ struct sockaddr_un unix_addr;
+ socklen_t unix_addr_len;
+ };
+ };
+};
+
+static pid_t __maybe_unused sys_gettid(void)
+{
+ return syscall(__NR_gettid);
+}
+
+static void __maybe_unused set_unix_address(struct service_fixture *const srv,
+ const unsigned short index)
+{
+ srv->unix_addr.sun_family = AF_UNIX;
+ sprintf(srv->unix_addr.sun_path,
+ "_selftests-landlock-abstract-unix-tid%d-index%d", sys_gettid(),
+ index);
+ srv->unix_addr_len = SUN_LEN(&srv->unix_addr);
+ srv->unix_addr.sun_path[0] = '\0';
+}
diff --git a/tools/testing/selftests/landlock/net_test.c b/tools/testing/selftests/landlock/net_test.c
index f21cfbbc3638..4e0aeb53b225 100644
--- a/tools/testing/selftests/landlock/net_test.c
+++ b/tools/testing/selftests/landlock/net_test.c
@@ -36,30 +36,6 @@ enum sandbox_type {
TCP_SANDBOX,
};
-struct protocol_variant {
- int domain;
- int type;
-};
-
-struct service_fixture {
- struct protocol_variant protocol;
- /* port is also stored in ipv4_addr.sin_port or ipv6_addr.sin6_port */
- unsigned short port;
- union {
- struct sockaddr_in ipv4_addr;
- struct sockaddr_in6 ipv6_addr;
- struct {
- struct sockaddr_un unix_addr;
- socklen_t unix_addr_len;
- };
- };
-};
-
-static pid_t sys_gettid(void)
-{
- return syscall(__NR_gettid);
-}
-
static int set_service(struct service_fixture *const srv,
const struct protocol_variant prot,
const unsigned short index)
@@ -92,12 +68,7 @@ static int set_service(struct service_fixture *const srv,
return 0;
case AF_UNIX:
- srv->unix_addr.sun_family = prot.domain;
- sprintf(srv->unix_addr.sun_path,
- "_selftests-landlock-net-tid%d-index%d", sys_gettid(),
- index);
- srv->unix_addr_len = SUN_LEN(&srv->unix_addr);
- srv->unix_addr.sun_path[0] = '\0';
+ set_unix_address(srv, index);
return 0;
}
return 1;
diff --git a/tools/testing/selftests/landlock/scoped_abstract_unix_test.c b/tools/testing/selftests/landlock/scoped_abstract_unix_test.c
new file mode 100644
index 000000000000..65c1ac2895a9
--- /dev/null
+++ b/tools/testing/selftests/landlock/scoped_abstract_unix_test.c
@@ -0,0 +1,931 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Landlock tests - Abstract Unix Socket
+ *
+ * Copyright © 2024 Tahera Fahimi <fahimitahera at gmail.com>
+ */
+
+#define _GNU_SOURCE
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/landlock.h>
+#include <sched.h>
+#include <signal.h>
+#include <stddef.h>
+#include <sys/prctl.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/un.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include "common.h"
+
+/* Number pending connections queue to be hold. */
+const short backlog = 10;
+
+static void create_fs_domain(struct __test_metadata *const _metadata)
+{
+ int ruleset_fd;
+ struct landlock_ruleset_attr ruleset_attr = {
+ .handled_access_fs = LANDLOCK_ACCESS_FS_READ_DIR,
+ };
+
+ ruleset_fd =
+ landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
+ EXPECT_LE(0, ruleset_fd)
+ {
+ TH_LOG("Failed to create a ruleset: %s", strerror(errno));
+ }
+ EXPECT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0));
+ EXPECT_EQ(0, landlock_restrict_self(ruleset_fd, 0));
+ EXPECT_EQ(0, close(ruleset_fd));
+}
+
+static void create_unix_domain(struct __test_metadata *const _metadata)
+{
+ int ruleset_fd;
+ const struct landlock_ruleset_attr ruleset_attr = {
+ .scoped = LANDLOCK_SCOPED_ABSTRACT_UNIX_SOCKET,
+ };
+
+ ruleset_fd =
+ landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
+ EXPECT_LE(0, ruleset_fd)
+ {
+ TH_LOG("Failed to create a ruleset: %s", strerror(errno));
+ }
+ enforce_ruleset(_metadata, ruleset_fd);
+ EXPECT_EQ(0, close(ruleset_fd));
+}
+
+/* clang-format off */
+FIXTURE(unix_socket) {};
+/* clang-format on */
+
+FIXTURE_VARIANT(unix_socket)
+{
+ bool domain_both;
+ bool domain_parent;
+ bool domain_child;
+ bool connect_to_parent;
+};
+
+FIXTURE_SETUP(unix_socket)
+{
+}
+
+FIXTURE_TEARDOWN(unix_socket)
+{
+}
+
+/*
+ * No domain
+ *
+ * P1-. P1 -> P2 : allow
+ * \ P2 -> P1 : allow
+ * 'P2
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(unix_socket, allow_without_domain_connect_to_parent) {
+ /* clang-format on */
+ .domain_both = false,
+ .domain_parent = false,
+ .domain_child = false,
+ .connect_to_parent = true,
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(unix_socket, allow_without_domain_connect_to_child) {
+ /* clang-format on */
+ .domain_both = false,
+ .domain_parent = false,
+ .domain_child = false,
+ .connect_to_parent = false,
+};
+
+/*
+ * Child domain
+ *
+ * P1--. P1 -> P2 : allow
+ * \ P2 -> P1 : deny
+ * .'-----.
+ * | P2 |
+ * '------'
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(unix_socket, deny_with_one_domain_connect_to_parent) {
+ /* clang-format on */
+ .domain_both = false,
+ .domain_parent = false,
+ .domain_child = true,
+ .connect_to_parent = true,
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(unix_socket, allow_with_one_domain_connect_to_child) {
+ /* clang-format on */
+ .domain_both = false,
+ .domain_parent = false,
+ .domain_child = true,
+ .connect_to_parent = false,
+};
+
+/*
+ * Parent domain
+ * .------.
+ * | P1 --. P1 -> P2 : deny
+ * '------' \ P2 -> P1 : allow
+ * '
+ * P2
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(unix_socket, allow_with_parent_domain_connect_to_parent) {
+ /* clang-format on */
+ .domain_both = false,
+ .domain_parent = true,
+ .domain_child = false,
+ .connect_to_parent = true,
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(unix_socket, deny_with_parent_domain_connect_to_child) {
+ /* clang-format on */
+ .domain_both = false,
+ .domain_parent = true,
+ .domain_child = false,
+ .connect_to_parent = false,
+};
+
+/*
+ * Parent + child domain (siblings)
+ * .------.
+ * | P1 ---. P1 -> P2 : deny
+ * '------' \ P2 -> P1 : deny
+ * .---'--.
+ * | P2 |
+ * '------'
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(unix_socket, deny_with_sibling_domain_connect_to_parent) {
+ /* clang-format on */
+ .domain_both = false,
+ .domain_parent = true,
+ .domain_child = true,
+ .connect_to_parent = true,
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(unix_socket, deny_with_sibling_domain_connect_to_child) {
+ /* clang-format on */
+ .domain_both = false,
+ .domain_parent = true,
+ .domain_child = true,
+ .connect_to_parent = false,
+};
+
+/*
+ * Same domain (inherited)
+ * .-------------.
+ * | P1----. | P1 -> P2 : allow
+ * | \ | P2 -> P1 : allow
+ * | ' |
+ * | P2 |
+ * '-------------'
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(unix_socket, allow_inherited_domain_connect_to_parent) {
+ /* clang-format on */
+ .domain_both = true,
+ .domain_parent = false,
+ .domain_child = false,
+ .connect_to_parent = true,
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(unix_socket, allow_inherited_domain_connect_to_child) {
+ /* clang-format on */
+ .domain_both = true,
+ .domain_parent = false,
+ .domain_child = false,
+ .connect_to_parent = false,
+};
+
+/*
+ * Inherited + child domain
+ * .-----------------.
+ * | P1----. | P1 -> P2 : allow
+ * | \ | P2 -> P1 : deny
+ * | .-'----. |
+ * | | P2 | |
+ * | '------' |
+ * '-----------------'
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(unix_socket, deny_nested_domain_connect_to_parent) {
+ /* clang-format on */
+ .domain_both = true,
+ .domain_parent = false,
+ .domain_child = true,
+ .connect_to_parent = true,
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(unix_socket, allow_nested_domain_connect_to_child) {
+ /* clang-format on */
+ .domain_both = true,
+ .domain_parent = false,
+ .domain_child = true,
+ .connect_to_parent = false,
+};
+
+/*
+ * Inherited + parent domain
+ * .-----------------.
+ * |.------. | P1 -> P2 : deny
+ * || P1 ----. | P2 -> P1 : allow
+ * |'------' \ |
+ * | ' |
+ * | P2 |
+ * '-----------------'
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(unix_socket, allow_with_nested_and_parent_domain_connect_to_parent) {
+ /* clang-format on */
+ .domain_both = true,
+ .domain_parent = true,
+ .domain_child = false,
+ .connect_to_parent = true,
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(unix_socket, deny_with_nested_and_parent_domain_connect_to_child) {
+ /* clang-format on */
+ .domain_both = true,
+ .domain_parent = true,
+ .domain_child = false,
+ .connect_to_parent = false,
+};
+
+/*
+ * Inherited + parent and child domain (siblings)
+ * .-----------------.
+ * | .------. | P1 -> P2 : deny
+ * | | P1 . | P2 -> P1 : deny
+ * | '------'\ |
+ * | \ |
+ * | .--'---. |
+ * | | P2 | |
+ * | '------' |
+ * '-----------------'
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(unix_socket, deny_with_forked_domain_connect_to_parent) {
+ /* clang-format on */
+ .domain_both = true,
+ .domain_parent = true,
+ .domain_child = true,
+ .connect_to_parent = true,
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(unix_socket, deny_with_forked_domain_connect_to_child) {
+ /* clang-format on */
+ .domain_both = true,
+ .domain_parent = true,
+ .domain_child = true,
+ .connect_to_parent = false,
+};
+
+/*
+ * Test unix_stream_connect() and unix_may_send() for parent and child,
+ * when they have scoped domain or no domain.
+ */
+TEST_F(unix_socket, abstract_unix_socket)
+{
+ struct service_fixture stream_address, dgram_address;
+ pid_t child;
+ bool can_connect_to_parent, can_connect_to_child;
+ int err, err_dgram, status;
+ int pipe_child[2], pipe_parent[2];
+ char buf_parent;
+
+ memset(&stream_address, 0, sizeof(stream_address));
+ memset(&dgram_address, 0, sizeof(dgram_address));
+ set_unix_address(&stream_address, 0);
+ set_unix_address(&dgram_address, 1);
+ /*
+ * can_connect_to_child is true if a parent process can connect to its
+ * child process. The parent process is not isolated from the child
+ * with a dedicated Landlock domain.
+ */
+ can_connect_to_child = !variant->domain_parent;
+ /*
+ * can_connect_to_parent is true if a child process can connect to its
+ * parent process. This depends on the child process is not isolated from
+ * the parent with a dedicated Landlock domain.
+ */
+ can_connect_to_parent = !variant->domain_child;
+
+ ASSERT_EQ(0, pipe2(pipe_child, O_CLOEXEC));
+ ASSERT_EQ(0, pipe2(pipe_parent, O_CLOEXEC));
+ if (variant->domain_both) {
+ create_unix_domain(_metadata);
+ if (!__test_passed(_metadata))
+ return;
+ }
+
+ child = fork();
+ ASSERT_LE(0, child);
+ if (child == 0) {
+ char buf_child;
+
+ ASSERT_EQ(0, close(pipe_parent[1]));
+ ASSERT_EQ(0, close(pipe_child[0]));
+ if (variant->domain_child)
+ create_unix_domain(_metadata);
+
+ /* Waits for the parent to be in a domain, if any. */
+ ASSERT_EQ(1, read(pipe_parent[0], &buf_child, 1));
+
+ if (variant->connect_to_parent) {
+ int client, dgram_client;
+
+ client = socket(AF_UNIX, SOCK_STREAM, 0);
+ dgram_client = socket(AF_UNIX, SOCK_DGRAM, 0);
+
+ ASSERT_NE(-1, client);
+ ASSERT_NE(-1, dgram_client);
+ ASSERT_EQ(1, read(pipe_parent[0], &buf_child, 1));
+
+ err = connect(client, &stream_address.unix_addr,
+ stream_address.unix_addr_len);
+ err_dgram = connect(dgram_client,
+ &dgram_address.unix_addr,
+ dgram_address.unix_addr_len);
+
+ if (can_connect_to_parent) {
+ EXPECT_EQ(0, err);
+ EXPECT_EQ(0, err_dgram);
+ } else {
+ EXPECT_EQ(-1, err);
+ EXPECT_EQ(-1, err_dgram);
+ EXPECT_EQ(EPERM, errno);
+ }
+ ASSERT_EQ(1, write(pipe_child[1], ".", 1));
+ ASSERT_EQ(0, close(client));
+ ASSERT_EQ(0, close(dgram_client));
+ } else {
+ int server, dgram_server;
+
+ server = socket(AF_UNIX, SOCK_STREAM, 0);
+ dgram_server = socket(AF_UNIX, SOCK_DGRAM, 0);
+ ASSERT_NE(-1, server);
+ ASSERT_NE(-1, dgram_server);
+
+ ASSERT_EQ(0, bind(server, &stream_address.unix_addr,
+ stream_address.unix_addr_len));
+ ASSERT_EQ(0,
+ bind(dgram_server, &dgram_address.unix_addr,
+ dgram_address.unix_addr_len));
+ ASSERT_EQ(0, listen(server, backlog));
+
+ /* signal to parent that child is listening */
+ ASSERT_EQ(1, write(pipe_child[1], ".", 1));
+ /* wait to connect */
+ ASSERT_EQ(1, read(pipe_parent[0], &buf_child, 1));
+ ASSERT_EQ(0, close(server));
+ ASSERT_EQ(0, close(dgram_server));
+ }
+ _exit(_metadata->exit_code);
+ return;
+ }
+
+ ASSERT_EQ(0, close(pipe_child[1]));
+ ASSERT_EQ(0, close(pipe_parent[0]));
+
+ if (variant->domain_parent)
+ create_unix_domain(_metadata);
+
+ /* Signals that the parent is in a domain, if any. */
+ ASSERT_EQ(1, write(pipe_parent[1], ".", 1));
+
+ if (!variant->connect_to_parent) {
+ int client, dgram_client;
+
+ client = socket(AF_UNIX, SOCK_STREAM, 0);
+ dgram_client = socket(AF_UNIX, SOCK_DGRAM, 0);
+ ASSERT_NE(-1, client);
+ ASSERT_NE(-1, dgram_client);
+
+ /* Waits for the child to listen */
+ ASSERT_EQ(1, read(pipe_child[0], &buf_parent, 1));
+ err = connect(client, &stream_address.unix_addr,
+ stream_address.unix_addr_len);
+ err_dgram = connect(dgram_client, &dgram_address.unix_addr,
+ dgram_address.unix_addr_len);
+
+ if (can_connect_to_child) {
+ EXPECT_EQ(0, err);
+ EXPECT_EQ(0, err_dgram);
+ } else {
+ EXPECT_EQ(-1, err);
+ EXPECT_EQ(-1, err_dgram);
+ EXPECT_EQ(EPERM, errno);
+ }
+ ASSERT_EQ(1, write(pipe_parent[1], ".", 1));
+ ASSERT_EQ(0, close(client));
+ ASSERT_EQ(0, close(dgram_client));
+ } else {
+ int server, dgram_server;
+
+ server = socket(AF_UNIX, SOCK_STREAM, 0);
+ dgram_server = socket(AF_UNIX, SOCK_DGRAM, 0);
+ ASSERT_NE(-1, server);
+ ASSERT_NE(-1, dgram_server);
+ ASSERT_EQ(0, bind(server, &stream_address.unix_addr,
+ stream_address.unix_addr_len));
+ ASSERT_EQ(0, bind(dgram_server, &dgram_address.unix_addr,
+ dgram_address.unix_addr_len));
+ ASSERT_EQ(0, listen(server, backlog));
+
+ /* signal to child that parent is listening */
+ ASSERT_EQ(1, write(pipe_parent[1], ".", 1));
+ ASSERT_EQ(1, read(pipe_child[0], &buf_parent, 1));
+
+ ASSERT_EQ(0, close(server));
+ ASSERT_EQ(0, close(dgram_server));
+ }
+
+ ASSERT_EQ(child, waitpid(child, &status, 0));
+ if (WIFSIGNALED(status) || !WIFEXITED(status) ||
+ WEXITSTATUS(status) != EXIT_SUCCESS)
+ _metadata->exit_code = KSFT_FAIL;
+}
+
+enum sandbox_type {
+ NO_SANDBOX,
+ SCOPE_SANDBOX,
+ /* Any other type of sandboxing domain */
+ OTHER_SANDBOX,
+};
+
+/* clang-format off */
+FIXTURE(optional_scoping) {};
+/* clang-format on */
+
+FIXTURE_VARIANT(optional_scoping)
+{
+ const int domain_all;
+ const int domain_parent;
+ const int domain_children;
+ const int domain_child;
+ const int domain_grand_child;
+ const int type;
+};
+
+FIXTURE_SETUP(optional_scoping)
+{
+}
+
+FIXTURE_TEARDOWN(optional_scoping)
+{
+}
+
+/*
+ * .-----------------.
+ * | ####### | P3 -> P2 : allow
+ * | P1----# P2 # | P3 -> P1 : deny
+ * | # | # |
+ * | # P3 # |
+ * | ####### |
+ * '-----------------'
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(optional_scoping, deny_scoped) {
+ .domain_all = OTHER_SANDBOX,
+ .domain_parent = NO_SANDBOX,
+ .domain_children = SCOPE_SANDBOX,
+ .domain_child = NO_SANDBOX,
+ .domain_grand_child = NO_SANDBOX,
+ .type = SOCK_DGRAM,
+ /* clang-format on */
+};
+
+/*
+ * ###################
+ * # ####### # P3 -> P2 : allow
+ * # P1----# P2 # # P3 -> P1 : deny
+ * # # | # #
+ * # # P3 # #
+ * # ####### #
+ * ###################
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(optional_scoping, all_scoped) {
+ .domain_all = SCOPE_SANDBOX,
+ .domain_parent = NO_SANDBOX,
+ .domain_children = SCOPE_SANDBOX,
+ .domain_child = NO_SANDBOX,
+ .domain_grand_child = NO_SANDBOX,
+ .type = SOCK_DGRAM,
+ /* clang-format on */
+};
+
+/*
+ * .-----------------.
+ * | .-----. | P3 -> P2 : allow
+ * | P1----| P2 | | P3 -> P1 : allow
+ * | | | |
+ * | | P3 | |
+ * | '-----' |
+ * '-----------------'
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(optional_scoping, allow_with_other_domain) {
+ .domain_all = OTHER_SANDBOX,
+ .domain_parent = NO_SANDBOX,
+ .domain_children = OTHER_SANDBOX,
+ .domain_child = NO_SANDBOX,
+ .domain_grand_child = NO_SANDBOX,
+ .type = SOCK_DGRAM,
+ /* clang-format on */
+};
+
+/*
+ * .----. ###### P3 -> P2 : allow
+ * | P1 |----# P2 # P3 -> P1 : allow
+ * '----' ######
+ * |
+ * P3
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(optional_scoping, allow_with_one_domain) {
+ .domain_all = NO_SANDBOX,
+ .domain_parent = OTHER_SANDBOX,
+ .domain_children = NO_SANDBOX,
+ .domain_child = SCOPE_SANDBOX,
+ .domain_grand_child = NO_SANDBOX,
+ .type = SOCK_DGRAM,
+ /* clang-format on */
+};
+
+/*
+ * ###### .-----. P3 -> P2 : allow
+ * # P1 #----| P2 | P3 -> P1 : allow
+ * ###### '-----'
+ * |
+ * P3
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(optional_scoping, allow_with_grand_parent_scoped) {
+ .domain_all = NO_SANDBOX,
+ .domain_parent = SCOPE_SANDBOX,
+ .domain_children = NO_SANDBOX,
+ .domain_child = OTHER_SANDBOX,
+ .domain_grand_child = NO_SANDBOX,
+ .type = SOCK_STREAM,
+ /* clang-format on */
+};
+
+/*
+ * ###### ###### P3 -> P2 : allow
+ * # P1 #----# P2 # P3 -> P1 : allow
+ * ###### ######
+ * |
+ * .----.
+ * | P3 |
+ * '----'
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(optional_scoping, allow_with_parents_domain) {
+ .domain_all = NO_SANDBOX,
+ .domain_parent = SCOPE_SANDBOX,
+ .domain_children = NO_SANDBOX,
+ .domain_child = SCOPE_SANDBOX,
+ .domain_grand_child = NO_SANDBOX,
+ .type = SOCK_STREAM,
+ /* clang-format on */
+};
+
+/*
+ * ###### P3 -> P2 : deny
+ * # P1 #----P2 P3 -> P1 : deny
+ * ###### |
+ * |
+ * ######
+ * # P3 #
+ * ######
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(optional_scoping, deny_with_self_and_parents_domain) {
+ .domain_all = NO_SANDBOX,
+ .domain_parent = SCOPE_SANDBOX,
+ .domain_children = NO_SANDBOX,
+ .domain_child = NO_SANDBOX,
+ .domain_grand_child = SCOPE_SANDBOX,
+ .type = SOCK_STREAM,
+ /* clang-format on */
+};
+
+/*
+ * Test UNIX_STREAM_CONNECT and UNIX_MAY_SEND for parent, child
+ * and grand child processes when they can have scoped or non-scoped
+ * domains.
+ */
+TEST_F(optional_scoping, unix_scoping)
+{
+ struct service_fixture parent_address;
+ pid_t child;
+ int status;
+ bool can_connect_to_parent, can_connect_to_child;
+ int pipe_parent[2];
+
+ memset(&parent_address, 0, sizeof(parent_address));
+ set_unix_address(&parent_address, 0);
+
+ can_connect_to_child = (variant->domain_grand_child != SCOPE_SANDBOX);
+ can_connect_to_parent = (can_connect_to_child &&
+ (variant->domain_children != SCOPE_SANDBOX));
+
+ ASSERT_EQ(0, pipe2(pipe_parent, O_CLOEXEC));
+
+ if (variant->domain_all == OTHER_SANDBOX)
+ create_fs_domain(_metadata);
+ else if (variant->domain_all == SCOPE_SANDBOX)
+ create_unix_domain(_metadata);
+
+ child = fork();
+ ASSERT_LE(0, child);
+ if (child == 0) {
+ int pipe_child[2];
+ pid_t grand_child;
+ struct service_fixture child_address;
+
+ memset(&child_address, 0, sizeof(child_address));
+ set_unix_address(&child_address, 1);
+
+ ASSERT_EQ(0, pipe2(pipe_child, O_CLOEXEC));
+
+ if (variant->domain_children == OTHER_SANDBOX)
+ create_fs_domain(_metadata);
+ else if (variant->domain_children == SCOPE_SANDBOX)
+ create_unix_domain(_metadata);
+
+ grand_child = fork();
+ ASSERT_LE(0, grand_child);
+ if (grand_child == 0) {
+ char buf1, buf2;
+ int err, client;
+
+ ASSERT_EQ(0, close(pipe_parent[1]));
+ ASSERT_EQ(0, close(pipe_child[1]));
+
+ if (variant->domain_grand_child == OTHER_SANDBOX)
+ create_fs_domain(_metadata);
+ else if (variant->domain_grand_child == SCOPE_SANDBOX)
+ create_unix_domain(_metadata);
+
+ client = socket(AF_UNIX, variant->type, 0);
+ ASSERT_NE(-1, client);
+
+ ASSERT_EQ(1, read(pipe_child[0], &buf2, 1));
+ err = connect(client, &child_address.unix_addr,
+ child_address.unix_addr_len);
+ if (can_connect_to_child) {
+ EXPECT_EQ(0, err);
+ } else {
+ EXPECT_EQ(-1, err);
+ EXPECT_EQ(EPERM, errno);
+ }
+
+ if (variant->type == SOCK_STREAM) {
+ EXPECT_EQ(0, close(client));
+ client = socket(AF_UNIX, variant->type, 0);
+ ASSERT_NE(-1, client);
+ }
+ ASSERT_EQ(1, read(pipe_parent[0], &buf1, 1));
+ err = connect(client, &parent_address.unix_addr,
+ parent_address.unix_addr_len);
+ if (can_connect_to_parent) {
+ EXPECT_EQ(0, err);
+ } else {
+ EXPECT_EQ(-1, err);
+ EXPECT_EQ(EPERM, errno);
+ }
+ EXPECT_EQ(0, close(client));
+
+ _exit(_metadata->exit_code);
+ return;
+ }
+ int child_server;
+
+ ASSERT_EQ(0, close(pipe_child[0]));
+ if (variant->domain_child == OTHER_SANDBOX)
+ create_fs_domain(_metadata);
+ else if (variant->domain_child == SCOPE_SANDBOX)
+ create_unix_domain(_metadata);
+
+ child_server = socket(AF_UNIX, variant->type, 0);
+ ASSERT_NE(-1, child_server);
+ ASSERT_EQ(0, bind(child_server, &child_address.unix_addr,
+ child_address.unix_addr_len));
+ if (variant->type == SOCK_STREAM)
+ ASSERT_EQ(0, listen(child_server, backlog));
+
+ ASSERT_EQ(1, write(pipe_child[1], ".", 1));
+ ASSERT_EQ(grand_child, waitpid(grand_child, &status, 0));
+ ASSERT_EQ(0, close(child_server));
+ return;
+ }
+ int parent_server;
+
+ ASSERT_EQ(0, close(pipe_parent[0]));
+
+ if (variant->domain_parent == OTHER_SANDBOX)
+ create_fs_domain(_metadata);
+ else if (variant->domain_parent == SCOPE_SANDBOX)
+ create_unix_domain(_metadata);
+
+ parent_server = socket(AF_UNIX, variant->type, 0);
+ ASSERT_NE(-1, parent_server);
+ ASSERT_EQ(0, bind(parent_server, &parent_address.unix_addr,
+ parent_address.unix_addr_len));
+
+ if (variant->type == SOCK_STREAM)
+ ASSERT_EQ(0, listen(parent_server, backlog));
+
+ ASSERT_EQ(1, write(pipe_parent[1], ".", 1));
+ ASSERT_EQ(child, waitpid(child, &status, 0));
+ ASSERT_EQ(0, close(parent_server));
+
+ if (WIFSIGNALED(status) || !WIFEXITED(status) ||
+ WEXITSTATUS(status) != EXIT_SUCCESS)
+ _metadata->exit_code = KSFT_FAIL;
+}
+
+/* clang-format off */
+FIXTURE(outside_socket) {};
+/* clang-format on */
+
+FIXTURE_VARIANT(outside_socket)
+{
+ const bool domain_server;
+ const bool domain_server_socket;
+ const int type;
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(outside_socket, allow_dgram_server_sock_domain) {
+ /* clang-format on */
+ .domain_server = false,
+ .domain_server_socket = true,
+ .type = SOCK_DGRAM,
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(outside_socket, deny_dgram_server_domain) {
+ /* clang-format on */
+ .domain_server = true,
+ .domain_server_socket = false,
+ .type = SOCK_DGRAM,
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(outside_socket, allow_stream_server_sock_domain) {
+ /* clang-format on */
+ .domain_server = false,
+ .domain_server_socket = true,
+ .type = SOCK_STREAM,
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(outside_socket, deny_stream_server_domain) {
+ /* clang-format on */
+ .domain_server = true,
+ .domain_server_socket = false,
+ .type = SOCK_STREAM,
+};
+
+FIXTURE_SETUP(outside_socket)
+{
+}
+
+FIXTURE_TEARDOWN(outside_socket)
+{
+}
+
+/* Test UNIX_STREAM_CONNECT and UNIX_MAY_SEND for parent and
+ * child processes when connecting socket has different domain
+ * than the process using it.
+ **/
+TEST_F(outside_socket, socket_with_different_domain)
+{
+ pid_t child;
+ int err, status;
+ int pipe_child[2], pipe_parent[2];
+ char buf_parent;
+ struct service_fixture address, transit_address;
+
+ ASSERT_EQ(0, pipe2(pipe_child, O_CLOEXEC));
+ ASSERT_EQ(0, pipe2(pipe_parent, O_CLOEXEC));
+
+ memset(&transit_address, 0, sizeof(transit_address));
+ memset(&address, 0, sizeof(address));
+ set_unix_address(&transit_address, 0);
+ set_unix_address(&address, 1);
+
+ child = fork();
+ ASSERT_LE(0, child);
+ if (child == 0) {
+ char buf_child;
+ int stream_server, client;
+
+ ASSERT_EQ(0, close(pipe_parent[1]));
+ ASSERT_EQ(0, close(pipe_child[0]));
+
+ /* client always has domain */
+ create_unix_domain(_metadata);
+
+ if (variant->domain_server_socket) {
+ int data_socket;
+ int fd_sock = socket(AF_UNIX, variant->type, 0);
+
+ ASSERT_NE(-1, fd_sock);
+
+ stream_server = socket(AF_UNIX, SOCK_STREAM, 0);
+
+ ASSERT_NE(-1, stream_server);
+ ASSERT_EQ(0, bind(stream_server,
+ &transit_address.unix_addr,
+ transit_address.unix_addr_len));
+ ASSERT_EQ(0, listen(stream_server, backlog));
+
+ ASSERT_EQ(1, write(pipe_child[1], ".", 1));
+
+ data_socket = accept(stream_server, NULL, NULL);
+
+ ASSERT_EQ(0, send_fd(data_socket, fd_sock));
+ ASSERT_EQ(0, close(fd_sock));
+ ASSERT_EQ(0, close(stream_server));
+ }
+
+ client = socket(AF_UNIX, variant->type, 0);
+ ASSERT_NE(-1, client);
+ /* wait for parent signal for connection */
+ ASSERT_EQ(1, read(pipe_parent[0], &buf_child, 1));
+
+ err = connect(client, &address.unix_addr,
+ address.unix_addr_len);
+ if (!variant->domain_server_socket) {
+ EXPECT_EQ(-1, err);
+ EXPECT_EQ(EPERM, errno);
+ } else {
+ EXPECT_EQ(0, err);
+ }
+ ASSERT_EQ(0, close(client));
+ _exit(_metadata->exit_code);
+ return;
+ }
+ int server_socket;
+
+ ASSERT_EQ(0, close(pipe_child[1]));
+ ASSERT_EQ(0, close(pipe_parent[0]));
+
+ if (!variant->domain_server_socket) {
+ server_socket = socket(AF_UNIX, variant->type, 0);
+ } else {
+ int cli = socket(AF_UNIX, SOCK_STREAM, 0);
+
+ ASSERT_NE(-1, cli);
+ ASSERT_EQ(1, read(pipe_child[0], &buf_parent, 1));
+ ASSERT_EQ(0, connect(cli, &transit_address.unix_addr,
+ transit_address.unix_addr_len));
+
+ server_socket = recv_fd(cli);
+ ASSERT_LE(0, server_socket);
+ ASSERT_EQ(0, close(cli));
+ }
+
+ ASSERT_NE(-1, server_socket);
+
+ if (variant->domain_server)
+ create_unix_domain(_metadata);
+
+ ASSERT_EQ(0, bind(server_socket, &address.unix_addr,
+ address.unix_addr_len));
+ if (variant->type == SOCK_STREAM)
+ ASSERT_EQ(0, listen(server_socket, backlog));
+ /* signal to child that parent is listening */
+ ASSERT_EQ(1, write(pipe_parent[1], ".", 1));
+
+ ASSERT_EQ(child, waitpid(child, &status, 0));
+ ASSERT_EQ(0, close(server_socket));
+
+ if (WIFSIGNALED(status) || !WIFEXITED(status) ||
+ WEXITSTATUS(status) != EXIT_SUCCESS)
+ _metadata->exit_code = KSFT_FAIL;
+}
+
+TEST_HARNESS_MAIN
--
2.34.1
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