sandbox/linux/bpf_dsl/bpf_dsl_impl.h

   1 // Copyright 2014 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_BPF_DSL_BPF_DSL_IMPL_H_
   6 #define SANDBOX_LINUX_BPF_DSL_BPF_DSL_IMPL_H_
   7
   8 #include "base/macros.h"
   9 #include "base/memory/ref_counted.h"
  10 #include "sandbox/linux/bpf_dsl/codegen.h"
  11 #include "sandbox/sandbox_export.h"
  12
  13 namespace sandbox {
  14 namespace bpf_dsl {
  15 class ErrorCode;
  16 class PolicyCompiler;
  17
  18 namespace internal {
  19
  20 // Internal interface implemented by BoolExpr implementations.
  21 class BoolExprImpl : public base::RefCounted<BoolExprImpl> {
  22  public:
  23   // Compile uses |pc| to emit a CodeGen::Node that conditionally continues
  24   // to either |then_node| or |false_node|, depending on whether the represented
  25   // boolean expression is true or false.
  26   virtual CodeGen::Node Compile(PolicyCompiler* pc,
  27                                 CodeGen::Node then_node,
  28                                 CodeGen::Node else_node) const = 0;
  29
  30  protected:
  31   BoolExprImpl() {}
  32   virtual ~BoolExprImpl() {}
  33
  34  private:
  35   friend class base::RefCounted<BoolExprImpl>;
  36   DISALLOW_COPY_AND_ASSIGN(BoolExprImpl);
  37 };
  38
  39 // Internal interface implemented by ResultExpr implementations.
  40 class ResultExprImpl : public base::RefCounted<ResultExprImpl> {
  41  public:
  42   // Compile uses |pc| to emit a CodeGen::Node that executes the
  43   // represented result expression.
  44   virtual CodeGen::Node Compile(PolicyCompiler* pc) const = 0;
  45
  46   // HasUnsafeTraps returns whether the result expression is or recursively
  47   // contains an unsafe trap expression.
  48   virtual bool HasUnsafeTraps() const;
  49
  50   // IsAllow returns whether the result expression is an "allow" result.
  51   virtual bool IsAllow() const;
  52
  53   // IsAllow returns whether the result expression is a "deny" result.
  54   virtual bool IsDeny() const;
  55
  56  protected:
  57   ResultExprImpl() {}
  58   virtual ~ResultExprImpl() {}
  59
  60  private:
  61   friend class base::RefCounted<ResultExprImpl>;
  62   DISALLOW_COPY_AND_ASSIGN(ResultExprImpl);
  63 };
  64
  65 }  // namespace internal
  66 }  // namespace bpf_dsl
  67 }  // namespace sandbox
  68
  69 #endif  // SANDBOX_LINUX_BPF_DSL_BPF_DSL_IMPL_H_