sandboxed-api/sandboxed_api/sandbox2/notify_test.cc
Christian Blichmann 21f7373e76 Initial changes to support AArch64
This is a work in progress:
- Syscall tables need work
- Only tested on real hardware using one of our test hosts

As a drive-by, this change also enables the open source version to function on
POWER.

Another side-effect of this change is that the default policies no longer
check for different host architectures at runtime. On x86_64, we do not need
to check for PPC or AArch64 specifice and vice versa.

PiperOrigin-RevId: 331137472
Change-Id: Ic6d6be5cbe61d83dbe13d5a0be036871754b2eb8
2020-09-11 06:34:27 -07:00

152 lines
5.0 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
//
// http://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/notify.h"
#include <syscall.h>
#include <memory>
#include <string>
#include <utility>
#include <vector>
#include <glog/logging.h>
#include "gmock/gmock.h"
#include "gtest/gtest.h"
#include "absl/memory/memory.h"
#include "absl/strings/str_join.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/sandbox2.h"
#include "sandboxed_api/sandbox2/syscall.h"
#include "sandboxed_api/sandbox2/testing.h"
#include "sandboxed_api/sandbox2/util/bpf_helper.h"
namespace sandbox2 {
namespace {
// Allow typical syscalls and call SECCOMP_RET_TRACE for personality syscall,
// chosen because unlikely to be called by a regular program.
std::unique_ptr<Policy> NotifyTestcasePolicy() {
return PolicyBuilder()
.DisableNamespaces()
.AllowStaticStartup()
.AllowExit()
.AllowRead()
.AllowWrite()
.AllowSyscall(__NR_close)
.AddPolicyOnSyscall(__NR_personality, {SANDBOX2_TRACE})
#ifdef __NR_open
.BlockSyscallWithErrno(__NR_open, ENOENT)
#endif
#ifdef __NR_access
.BlockSyscallWithErrno(__NR_access, ENOENT)
#endif
.BlockSyscallWithErrno(__NR_openat, ENOENT)
.BlockSyscallWithErrno(__NR_prlimit64, EPERM)
.BuildOrDie();
}
// If syscall and its arguments don't match the expected ones, return the
// opposite of the requested values (allow/disallow) to indicate an error.
class PersonalityNotify : public Notify {
public:
explicit PersonalityNotify(bool allow) : allow_(allow) {}
bool EventSyscallTrap(const Syscall& syscall) override {
if (syscall.nr() != __NR_personality) {
LOG(ERROR) << "kSyscall==" << syscall.nr();
return (!allow_);
}
Syscall::Args expected_args = {0x1, 0x2, 0x3, 0x4, 0x5, 0x6};
if (syscall.args() != expected_args) {
LOG(ERROR) << "args=={" << absl::StrJoin(syscall.args(), ", ") << "}";
return (!allow_);
}
return allow_;
}
private:
// The intended return value from EventSyscallTrap in case all registers
// match.
bool allow_;
};
// Print the newly created PID, and exchange data over Comms before sandboxing.
class PidCommsNotify : public Notify {
public:
bool EventStarted(pid_t pid, Comms* comms) final {
LOG(INFO) << "The newly created PID: " << pid;
bool v;
return comms->RecvBool(&v);
}
};
// Test EventSyscallTrap on personality syscall and allow it.
TEST(NotifyTest, AllowPersonality) {
SKIP_SANITIZERS_AND_COVERAGE;
const std::string path = GetTestSourcePath("sandbox2/testcases/personality");
std::vector<std::string> args = {path};
auto executor = absl::make_unique<Executor>(path, args);
auto policy = NotifyTestcasePolicy();
ASSERT_THAT(policy, testing::Not(testing::IsNull()));
auto notify = absl::make_unique<PersonalityNotify>(true);
Sandbox2 s2(std::move(executor), std::move(policy), std::move(notify));
auto result = s2.Run();
ASSERT_EQ(result.final_status(), Result::OK);
ASSERT_EQ(result.reason_code(), 22);
}
// Test EventSyscallTrap on personality syscall and disallow it.
TEST(NotifyTest, DisallowPersonality) {
SKIP_SANITIZERS_AND_COVERAGE;
const std::string path = GetTestSourcePath("sandbox2/testcases/personality");
std::vector<std::string> args = {path};
auto executor = absl::make_unique<Executor>(path, args);
auto policy = NotifyTestcasePolicy();
ASSERT_THAT(policy, testing::Not(testing::IsNull()));
auto notify = absl::make_unique<PersonalityNotify>(false);
Sandbox2 s2(std::move(executor), std::move(policy), std::move(notify));
auto result = s2.Run();
ASSERT_EQ(result.final_status(), Result::VIOLATION);
ASSERT_EQ(result.reason_code(), __NR_personality);
}
// Test EventStarted by exchanging data after started but before sandboxed.
TEST(NotifyTest, PrintPidAndComms) {
SKIP_SANITIZERS_AND_COVERAGE;
const std::string path = GetTestSourcePath("sandbox2/testcases/pidcomms");
std::vector<std::string> args = {path};
auto executor = absl::make_unique<Executor>(path, args);
executor->set_enable_sandbox_before_exec(false);
auto policy = NotifyTestcasePolicy();
ASSERT_THAT(policy, testing::Not(testing::IsNull()));
auto notify = absl::make_unique<PidCommsNotify>();
Sandbox2 s2(std::move(executor), std::move(policy), std::move(notify));
auto result = s2.Run();
ASSERT_EQ(result.final_status(), Result::OK);
ASSERT_EQ(result.reason_code(), 33);
}
} // namespace
} // namespace sandbox2