sandbox/linux/seccomp-bpf/bpf_tests.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef SANDBOX_LINUX_SECCOMP_BPF_BPF_TESTS_H__
   6 #define SANDBOX_LINUX_SECCOMP_BPF_BPF_TESTS_H__
   7
   8 #include "base/logging.h"
   9 #include "base/macros.h"
  10 #include "build/build_config.h"
  11 #include "sandbox/linux/seccomp-bpf/bpf_tester_compatibility_delegate.h"
  12 #include "sandbox/linux/tests/unit_tests.h"
  13
  14 namespace sandbox {
  15
  16 // BPF_TEST_C() is a special version of SANDBOX_TEST(). It runs a test function
  17 // in a sub-process, under a seccomp-bpf policy specified in
  18 // |bpf_policy_class_name| without failing on configurations that are allowed
  19 // to not support seccomp-bpf in their kernels.
  20 // This is the preferred format for new BPF tests. |bpf_policy_class_name| is a
  21 // class name  (which will be default-constructed) that implements the
  22 // Policy interface.
  23 // The test function's body can simply follow. Test functions should use
  24 // the BPF_ASSERT macros defined below, not GTEST's macros. The use of
  25 // CHECK* macros is supported but less robust.
  26 #define BPF_TEST_C(test_case_name, test_name, bpf_policy_class_name)     \
  27   BPF_DEATH_TEST_C(                                                      \
  28       test_case_name, test_name, DEATH_SUCCESS(), bpf_policy_class_name)
  29
  30 // Identical to BPF_TEST_C but allows to specify the nature of death.
  31 #define BPF_DEATH_TEST_C(                                            \
  32     test_case_name, test_name, death, bpf_policy_class_name)         \
  33   void BPF_TEST_C_##test_name();                                     \
  34   TEST(test_case_name, DISABLE_ON_TSAN(test_name)) {                 \
  35     sandbox::SandboxBPFTestRunner bpf_test_runner(                   \
  36         new sandbox::BPFTesterSimpleDelegate<bpf_policy_class_name>( \
  37             BPF_TEST_C_##test_name));                                \
  38     sandbox::UnitTests::RunTestInProcess(&bpf_test_runner, death);   \
  39   }                                                                  \
  40   void BPF_TEST_C_##test_name()
  41
  42 // This form of BPF_TEST is a little verbose and should be reserved for complex
  43 // tests where a lot of control is required.
  44 // |bpf_tester_delegate_class| must be a classname implementing the
  45 // BPFTesterDelegate interface.
  46 #define BPF_TEST_D(test_case_name, test_name, bpf_tester_delegate_class)     \
  47   BPF_DEATH_TEST_D(                                                          \
  48       test_case_name, test_name, DEATH_SUCCESS(), bpf_tester_delegate_class)
  49
  50 // Identical to BPF_TEST_D but allows to specify the nature of death.
  51 #define BPF_DEATH_TEST_D(                                          \
  52     test_case_name, test_name, death, bpf_tester_delegate_class)   \
  53   TEST(test_case_name, DISABLE_ON_TSAN(test_name)) {               \
  54     sandbox::SandboxBPFTestRunner bpf_test_runner(                 \
  55         new bpf_tester_delegate_class());                          \
  56     sandbox::UnitTests::RunTestInProcess(&bpf_test_runner, death); \
  57   }
  58
  59 // Assertions are handled exactly the same as with a normal SANDBOX_TEST()
  60 #define BPF_ASSERT SANDBOX_ASSERT
  61 #define BPF_ASSERT_EQ(x, y) BPF_ASSERT((x) == (y))
  62 #define BPF_ASSERT_NE(x, y) BPF_ASSERT((x) != (y))
  63 #define BPF_ASSERT_LT(x, y) BPF_ASSERT((x) < (y))
  64 #define BPF_ASSERT_GT(x, y) BPF_ASSERT((x) > (y))
  65 #define BPF_ASSERT_LE(x, y) BPF_ASSERT((x) <= (y))
  66 #define BPF_ASSERT_GE(x, y) BPF_ASSERT((x) >= (y))
  67
  68 // This form of BPF_TEST is now discouraged (but still allowed) in favor of
  69 // BPF_TEST_D and BPF_TEST_C.
  70 // The |policy| parameter should be a Policy subclass.
  71 // BPF_TEST() takes a C++ data type as an fourth parameter. A variable
  72 // of this type will be allocated and a pointer to it will be
  73 // available within the test function as "BPF_AUX". The pointer will
  74 // also be passed as an argument to the policy's constructor. Policies
  75 // would typically use it as an argument to SandboxBPF::Trap(), if
  76 // they want to communicate data between the BPF_TEST() and a Trap()
  77 // function. The life-time of this object is the same as the life-time
  78 // of the process running under the seccomp-bpf policy.
  79 // |aux| must not be void.
  80 #define BPF_TEST(test_case_name, test_name, policy, aux) \
  81   BPF_DEATH_TEST(test_case_name, test_name, DEATH_SUCCESS(), policy, aux)
  82
  83 // A BPF_DEATH_TEST is just the same as a BPF_TEST, but it assumes that the
  84 // test will fail with a particular known error condition. Use the DEATH_XXX()
  85 // macros from unit_tests.h to specify the expected error condition.
  86 #define BPF_DEATH_TEST(test_case_name, test_name, death, policy, aux) \
  87   void BPF_TEST_##test_name(aux* BPF_AUX);                            \
  88   TEST(test_case_name, DISABLE_ON_TSAN(test_name)) {                  \
  89     sandbox::SandboxBPFTestRunner bpf_test_runner(                    \
  90         new sandbox::BPFTesterCompatibilityDelegate<policy, aux>(     \
  91             BPF_TEST_##test_name));                                   \
  92     sandbox::UnitTests::RunTestInProcess(&bpf_test_runner, death);    \
  93   }                                                                   \
  94   void BPF_TEST_##test_name(aux* BPF_AUX)
  95
  96 // This class takes a simple function pointer as a constructor parameter and a
  97 // class name as a template parameter to implement the BPFTesterDelegate
  98 // interface which can be used to build BPF unittests with
  99 // the SandboxBPFTestRunner class.
 100 template <class PolicyClass>
 101 class BPFTesterSimpleDelegate : public BPFTesterDelegate {
 102  public:
 103   explicit BPFTesterSimpleDelegate(void (*test_function)(void))
 104       : test_function_(test_function) {}
 105   virtual ~BPFTesterSimpleDelegate() {}
 106
 107   virtual scoped_ptr<bpf_dsl::Policy> GetSandboxBPFPolicy() override {
 108     return scoped_ptr<bpf_dsl::Policy>(new PolicyClass());
 109   }
 110   virtual void RunTestFunction() override {
 111     DCHECK(test_function_);
 112     test_function_();
 113   }
 114
 115  private:
 116   void (*test_function_)(void);
 117   DISALLOW_COPY_AND_ASSIGN(BPFTesterSimpleDelegate);
 118 };
 119
 120 }  // namespace sandbox
 121
 122 #endif  // SANDBOX_LINUX_SECCOMP_BPF_BPF_TESTS_H__