sandboxed-api/sandboxed_api/sandbox2/namespace_test.cc
Christian Blichmann d451478e26 Change license link to HTTPS URL
PiperOrigin-RevId: 424811734
Change-Id: If5ea692edc56ddc9c99fd478673df41c0246e9cc
2022-01-28 01:39:09 -08:00

220 lines
7.2 KiB
C++

// Copyright 2019 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include "sandboxed_api/sandbox2/namespace.h"
#include <fcntl.h>
#include <sys/socket.h>
#include <syscall.h>
#include <unistd.h>
#include <initializer_list>
#include <memory>
#include <utility>
#include <glog/logging.h>
#include "gmock/gmock.h"
#include "gtest/gtest.h"
#include "absl/memory/memory.h"
#include "absl/strings/numbers.h"
#include "absl/strings/str_cat.h"
#include "sandboxed_api/config.h"
#include "sandboxed_api/sandbox2/comms.h"
#include "sandboxed_api/sandbox2/executor.h"
#include "sandboxed_api/sandbox2/policy.h"
#include "sandboxed_api/sandbox2/policybuilder.h"
#include "sandboxed_api/sandbox2/result.h"
#include "sandboxed_api/sandbox2/sandbox2.h"
#include "sandboxed_api/testing.h"
#include "sandboxed_api/util/fileops.h"
#include "sandboxed_api/util/status_matchers.h"
#include "sandboxed_api/util/temp_file.h"
namespace sandbox2 {
namespace {
namespace file_util = ::sapi::file_util;
using ::sapi::CreateNamedTempFile;
using ::sapi::GetTestSourcePath;
using ::sapi::GetTestTempPath;
using ::testing::Eq;
using ::testing::Ne;
int RunSandboxeeWithArgsAndPolicy(const std::string& sandboxee,
std::initializer_list<std::string> args,
std::unique_ptr<Policy> policy) {
Sandbox2 sandbox(absl::make_unique<Executor>(sandboxee, args),
std::move(policy));
Result result = sandbox.Run();
EXPECT_THAT(result.final_status(), Eq(Result::OK));
return result.reason_code();
}
constexpr absl::string_view kNamespaceTestBinary =
"sandbox2/testcases/namespace";
constexpr absl::string_view kHostnameTestBinary = "sandbox2/testcases/hostname";
TEST(NamespaceTest, FileNamespaceWorks) {
// Mount /binary_path RO and check that it exists and is readable.
// /etc/passwd should not exist.
const std::string path = GetTestSourcePath(kNamespaceTestBinary);
int reason_code = RunSandboxeeWithArgsAndPolicy(
path, {path, "0", "/binary_path", "/etc/passwd"},
PolicyBuilder()
.DangerDefaultAllowAll() // Do not restrict syscalls
.AddFileAt(path, "/binary_path")
.BuildOrDie());
EXPECT_THAT(reason_code, Eq(2));
}
TEST(NamespaceTest, ReadOnlyIsRespected) {
// Mount temporary file as RO and check that it actually is RO.
auto [name, fd] = CreateNamedTempFile(GetTestTempPath("temp_file")).value();
file_util::fileops::FDCloser temp_closer(fd);
const std::string path = GetTestSourcePath(kNamespaceTestBinary);
{
// Check that it is readable
int reason_code = RunSandboxeeWithArgsAndPolicy(
path, {path, "0", "/temp_file"},
PolicyBuilder()
.DangerDefaultAllowAll() // Do not restrict syscalls
.AddFileAt(name, "/temp_file")
.BuildOrDie());
EXPECT_THAT(reason_code, Eq(0));
}
{
// Now check that it is not writeable
int reason_code = RunSandboxeeWithArgsAndPolicy(
path, {path, "1", "/temp_file"},
PolicyBuilder()
.DangerDefaultAllowAll() // Do not restrict syscalls
.AddFileAt(name, "/temp_file")
.BuildOrDie());
EXPECT_THAT(reason_code, Eq(1));
}
}
TEST(NamespaceTest, UserNamespaceWorks) {
const std::string path = GetTestSourcePath(kNamespaceTestBinary);
// Check that getpid() returns 2 (which is the case inside pid NS).
{
int reason_code = RunSandboxeeWithArgsAndPolicy(
path, {path, "2"},
PolicyBuilder()
.DangerDefaultAllowAll() // Do not restrict syscalls
.BuildOrDie());
EXPECT_THAT(reason_code, Eq(0));
}
// Validate that getpid() does not return 2 when outside of a pid NS.
{
int reason_code = RunSandboxeeWithArgsAndPolicy(
path, {path, "2"},
PolicyBuilder()
.DisableNamespaces()
.DangerDefaultAllowAll() // Do not restrict syscalls
.BuildOrDie());
EXPECT_THAT(reason_code, Ne(0));
}
}
TEST(NamespaceTest, UserNamespaceIDMapWritten) {
// Check that the idmap is initialized before the sandbox application is
// started.
const std::string path = GetTestSourcePath(kNamespaceTestBinary);
{
int reason_code = RunSandboxeeWithArgsAndPolicy(
path, {path, "3", "1000", "1000"},
PolicyBuilder()
.DangerDefaultAllowAll() // Do not restrict syscalls
.BuildOrDie());
EXPECT_THAT(reason_code, Eq(0));
}
// Check that the uid/gid is the same when not using namespaces.
{
int reason_code = RunSandboxeeWithArgsAndPolicy(
path, {path, "3", absl::StrCat(getuid()), absl::StrCat(getgid())},
PolicyBuilder()
.DisableNamespaces()
.DangerDefaultAllowAll() // Do not restrict syscalls
.BuildOrDie());
EXPECT_THAT(reason_code, Eq(0));
}
}
TEST(NamespaceTest, RootReadOnly) {
// Mount rw tmpfs at /tmp and check it is RW.
// Check also that / is RO.
const std::string path = GetTestSourcePath(kNamespaceTestBinary);
int reason_code = RunSandboxeeWithArgsAndPolicy(
path, {path, "4", "/tmp/testfile", "/testfile"},
PolicyBuilder()
.DangerDefaultAllowAll() // Do not restrict syscalls
.AddTmpfs("/tmp", /*size=*/4ULL << 20 /* 4 MiB */)
.BuildOrDie());
EXPECT_THAT(reason_code, Eq(2));
}
TEST(NamespaceTest, RootWritable) {
// Mount root rw and check it
const std::string path = GetTestSourcePath(kNamespaceTestBinary);
int reason_code = RunSandboxeeWithArgsAndPolicy(
path, {path, "4", "/testfile"},
PolicyBuilder()
.DangerDefaultAllowAll() // Do not restrict syscalls
.SetRootWritable()
.BuildOrDie());
EXPECT_THAT(reason_code, Eq(0));
}
TEST(HostnameTest, None) {
const std::string path = GetTestSourcePath(kHostnameTestBinary);
int reason_code = RunSandboxeeWithArgsAndPolicy(
path, {path, "sandbox2"},
PolicyBuilder()
.DisableNamespaces()
.DangerDefaultAllowAll() // Do not restrict syscalls
.BuildOrDie());
EXPECT_THAT(reason_code, Eq(1));
}
TEST(HostnameTest, Default) {
const std::string path = GetTestSourcePath(kHostnameTestBinary);
int reason_code = RunSandboxeeWithArgsAndPolicy(
path, {path, "sandbox2"},
PolicyBuilder()
.DangerDefaultAllowAll() // Do not restrict syscalls
.BuildOrDie());
EXPECT_THAT(reason_code, Eq(0));
}
TEST(HostnameTest, Configured) {
const std::string path = GetTestSourcePath(kHostnameTestBinary);
int reason_code = RunSandboxeeWithArgsAndPolicy(
path, {path, "configured"},
PolicyBuilder()
.DangerDefaultAllowAll() // Do not restrict syscalls
.SetHostname("configured")
.BuildOrDie());
EXPECT_THAT(reason_code, Eq(0));
}
} // namespace
} // namespace sandbox2