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      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/basictypes.h"
      9 #include "build/build_config.h"
     10 #include "sandbox/linux/seccomp-bpf/bpf_tester_compatibility_delegate.h"
     11 #include "sandbox/linux/tests/unit_tests.h"
     12 
     13 namespace sandbox {
     14 
     15 // BPF_TEST_C() is a special version of SANDBOX_TEST(). It runs a test function
     16 // in a sub-process, under a seccomp-bpf policy specified in
     17 // |bpf_policy_class_name| without failing on configurations that are allowed
     18 // to not support seccomp-bpf in their kernels.
     19 // This is the preferred format for new BPF tests. |bpf_policy_class_name| is a
     20 // class name  (which will be default-constructed) that implements the
     21 // SandboxBPFPolicy interface.
     22 // The test function's body can simply follow. Test functions should use
     23 // the BPF_ASSERT macros defined below, not GTEST's macros. The use of
     24 // CHECK* macros is supported but less robust.
     25 #define BPF_TEST_C(test_case_name, test_name, bpf_policy_class_name)     \
     26   BPF_DEATH_TEST_C(                                                      \
     27       test_case_name, test_name, DEATH_SUCCESS(), bpf_policy_class_name)
     28 
     29 // Identical to BPF_TEST_C but allows to specify the nature of death.
     30 #define BPF_DEATH_TEST_C(                                            \
     31     test_case_name, test_name, death, bpf_policy_class_name)         \
     32   void BPF_TEST_C_##test_name();                                     \
     33   TEST(test_case_name, DISABLE_ON_TSAN(test_name)) {                 \
     34     sandbox::SandboxBPFTestRunner bpf_test_runner(                   \
     35         new sandbox::BPFTesterSimpleDelegate<bpf_policy_class_name>( \
     36             BPF_TEST_C_##test_name));                                \
     37     sandbox::UnitTests::RunTestInProcess(&bpf_test_runner, death);   \
     38   }                                                                  \
     39   void BPF_TEST_C_##test_name()
     40 
     41 // This form of BPF_TEST is a little verbose and should be reserved for complex
     42 // tests where a lot of control is required.
     43 // |bpf_tester_delegate_class| must be a classname implementing the
     44 // BPFTesterDelegate interface.
     45 #define BPF_TEST_D(test_case_name, test_name, bpf_tester_delegate_class)     \
     46   BPF_DEATH_TEST_D(                                                          \
     47       test_case_name, test_name, DEATH_SUCCESS(), bpf_tester_delegate_class)
     48 
     49 // Identical to BPF_TEST_D but allows to specify the nature of death.
     50 #define BPF_DEATH_TEST_D(                                          \
     51     test_case_name, test_name, death, bpf_tester_delegate_class)   \
     52   TEST(test_case_name, DISABLE_ON_TSAN(test_name)) {               \
     53     sandbox::SandboxBPFTestRunner bpf_test_runner(                 \
     54         new bpf_tester_delegate_class());                          \
     55     sandbox::UnitTests::RunTestInProcess(&bpf_test_runner, death); \
     56   }
     57 
     58 // Assertions are handled exactly the same as with a normal SANDBOX_TEST()
     59 #define BPF_ASSERT SANDBOX_ASSERT
     60 #define BPF_ASSERT_EQ(x, y) BPF_ASSERT((x) == (y))
     61 #define BPF_ASSERT_NE(x, y) BPF_ASSERT((x) != (y))
     62 #define BPF_ASSERT_LT(x, y) BPF_ASSERT((x) < (y))
     63 #define BPF_ASSERT_GT(x, y) BPF_ASSERT((x) > (y))
     64 #define BPF_ASSERT_LE(x, y) BPF_ASSERT((x) <= (y))
     65 #define BPF_ASSERT_GE(x, y) BPF_ASSERT((x) >= (y))
     66 
     67 // This form of BPF_TEST is now discouraged (but still allowed) in favor of
     68 // BPF_TEST_D and BPF_TEST_C.
     69 // The |policy| parameter should be a SyscallEvaluator function pointer
     70 // (which is now a deprecated way of expressing policies).
     71 // BPF_TEST() takes a C++ data type as an optional fourth parameter. If
     72 // present, this sets up a variable that can be accessed as "BPF_AUX". This
     73 // variable will be passed as an argument to the "policy" function. Policies
     74 // would typically use it as an argument to SandboxBPF::Trap(), if they want to
     75 // communicate data between the BPF_TEST() and a Trap() function. The life-time
     76 // of this object is the same as the life-time of the process running under the
     77 // seccomp-bpf policy.
     78 // The type specified in |aux| and the last parameter of the policy function
     79 // must be compatible. |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(                                                   \
     88       sandbox::BPFTesterCompatibilityDelegate<aux>::AuxType* BPF_AUX);         \
     89   TEST(test_case_name, DISABLE_ON_TSAN(test_name)) {                           \
     90     sandbox::SandboxBPFTestRunner bpf_test_runner(                             \
     91         new sandbox::BPFTesterCompatibilityDelegate<aux>(BPF_TEST_##test_name, \
     92                                                          policy));             \
     93     sandbox::UnitTests::RunTestInProcess(&bpf_test_runner, death);             \
     94   }                                                                            \
     95   void BPF_TEST_##test_name(                                                   \
     96       sandbox::BPFTesterCompatibilityDelegate<aux>::AuxType* BPF_AUX)
     97 
     98 // This class takes a simple function pointer as a constructor parameter and a
     99 // class name as a template parameter to implement the BPFTesterDelegate
    100 // interface which can be used to build BPF unittests with
    101 // the SandboxBPFTestRunner class.
    102 template <class PolicyClass>
    103 class BPFTesterSimpleDelegate : public BPFTesterDelegate {
    104  public:
    105   explicit BPFTesterSimpleDelegate(void (*test_function)(void))
    106       : test_function_(test_function) {}
    107   virtual ~BPFTesterSimpleDelegate() {}
    108 
    109   virtual scoped_ptr<SandboxBPFPolicy> GetSandboxBPFPolicy() OVERRIDE {
    110     return scoped_ptr<SandboxBPFPolicy>(new PolicyClass());
    111   }
    112   virtual void RunTestFunction() OVERRIDE {
    113     DCHECK(test_function_);
    114     test_function_();
    115   }
    116 
    117  private:
    118   void (*test_function_)(void);
    119   DISALLOW_COPY_AND_ASSIGN(BPFTesterSimpleDelegate);
    120 };
    121 
    122 }  // namespace sandbox
    123 
    124 #endif  // SANDBOX_LINUX_SECCOMP_BPF_BPF_TESTS_H__
    125