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 EXTENSIONS_COMMON_PERMISSIONS_SET_DISJUNCTION_PERMISSION_H_
6#define EXTENSIONS_COMMON_PERMISSIONS_SET_DISJUNCTION_PERMISSION_H_
7
8#include <set>
9#include <string>
10
11#include "base/json/json_writer.h"
12#include "base/memory/scoped_ptr.h"
13#include "base/values.h"
14#include "extensions/common/extension_messages.h"
15#include "extensions/common/permissions/api_permission.h"
16#include "ipc/ipc_message.h"
17#include "ipc/ipc_message_utils.h"
18
19namespace extensions {
20
21// An abstract base class for permissions that are represented by the
22// disjunction of a set of conditions.  Each condition is represented by a
23// |PermissionDataType| (e.g. SocketPermissionData).  If an
24// APIPermission::CheckParam matches any of the conditions in the set, the
25// permission is granted.
26//
27// For an example of how to use this class, see SocketPermission.
28template <class PermissionDataType, class DerivedType>
29class SetDisjunctionPermission : public APIPermission {
30 public:
31  explicit SetDisjunctionPermission(const APIPermissionInfo* info)
32      : APIPermission(info) {}
33
34  ~SetDisjunctionPermission() {}
35
36  // APIPermission overrides
37  virtual bool HasMessages() const OVERRIDE { return !data_set_.empty(); }
38
39  virtual bool Check(const APIPermission::CheckParam* param) const OVERRIDE {
40    for (typename std::set<PermissionDataType>::const_iterator i =
41             data_set_.begin();
42         i != data_set_.end();
43         ++i) {
44      if (i->Check(param))
45        return true;
46    }
47    return false;
48  }
49
50  virtual bool Contains(const APIPermission* rhs) const OVERRIDE {
51    CHECK(rhs->info() == info());
52    const SetDisjunctionPermission* perm =
53        static_cast<const SetDisjunctionPermission*>(rhs);
54    return base::STLIncludes<std::set<PermissionDataType> >(
55        data_set_, perm->data_set_);
56  }
57
58  virtual bool Equal(const APIPermission* rhs) const OVERRIDE {
59    CHECK(rhs->info() == info());
60    const SetDisjunctionPermission* perm =
61        static_cast<const SetDisjunctionPermission*>(rhs);
62    return data_set_ == perm->data_set_;
63  }
64
65  virtual APIPermission* Clone() const OVERRIDE {
66    SetDisjunctionPermission* result = new DerivedType(info());
67    result->data_set_ = data_set_;
68    return result;
69  }
70
71  virtual APIPermission* Diff(const APIPermission* rhs) const OVERRIDE {
72    CHECK(rhs->info() == info());
73    const SetDisjunctionPermission* perm =
74        static_cast<const SetDisjunctionPermission*>(rhs);
75    scoped_ptr<SetDisjunctionPermission> result(new DerivedType(info()));
76    result->data_set_ = base::STLSetDifference<std::set<PermissionDataType> >(
77        data_set_, perm->data_set_);
78    return result->data_set_.empty() ? NULL : result.release();
79  }
80
81  virtual APIPermission* Union(const APIPermission* rhs) const OVERRIDE {
82    CHECK(rhs->info() == info());
83    const SetDisjunctionPermission* perm =
84        static_cast<const SetDisjunctionPermission*>(rhs);
85    scoped_ptr<SetDisjunctionPermission> result(new DerivedType(info()));
86    result->data_set_ = base::STLSetUnion<std::set<PermissionDataType> >(
87        data_set_, perm->data_set_);
88    return result.release();
89  }
90
91  virtual APIPermission* Intersect(const APIPermission* rhs) const OVERRIDE {
92    CHECK(rhs->info() == info());
93    const SetDisjunctionPermission* perm =
94        static_cast<const SetDisjunctionPermission*>(rhs);
95    scoped_ptr<SetDisjunctionPermission> result(new DerivedType(info()));
96    result->data_set_ = base::STLSetIntersection<std::set<PermissionDataType> >(
97        data_set_, perm->data_set_);
98    return result->data_set_.empty() ? NULL : result.release();
99  }
100
101  virtual bool FromValue(
102      const base::Value* value,
103      std::string* error,
104      std::vector<std::string>* unhandled_permissions) OVERRIDE {
105    data_set_.clear();
106    const base::ListValue* list = NULL;
107
108    if (!value || !value->GetAsList(&list) || list->GetSize() == 0) {
109      if (error)
110        *error = "NULL or empty permission list";
111      return false;
112    }
113
114    for (size_t i = 0; i < list->GetSize(); ++i) {
115      const base::Value* item_value = NULL;
116      bool got_item = list->Get(i, &item_value);
117      DCHECK(got_item);
118      DCHECK(item_value);
119
120      PermissionDataType data;
121      if (data.FromValue(item_value)) {
122        data_set_.insert(data);
123      } else {
124        std::string unknown_permission;
125        base::JSONWriter::Write(item_value, &unknown_permission);
126        if (unhandled_permissions) {
127          unhandled_permissions->push_back(unknown_permission);
128        } else {
129          if (error) {
130            *error = "Cannot parse an item from the permission list: " +
131                     unknown_permission;
132          }
133          return false;
134        }
135      }
136    }
137    return true;
138  }
139
140  virtual scoped_ptr<base::Value> ToValue() const OVERRIDE {
141    base::ListValue* list = new base::ListValue();
142    typename std::set<PermissionDataType>::const_iterator i;
143    for (i = data_set_.begin(); i != data_set_.end(); ++i) {
144      scoped_ptr<base::Value> item_value(i->ToValue());
145      list->Append(item_value.release());
146    }
147    return scoped_ptr<base::Value>(list);
148  }
149
150  virtual void Write(IPC::Message* m) const OVERRIDE {
151    IPC::WriteParam(m, data_set_);
152  }
153
154  virtual bool Read(const IPC::Message* m, PickleIterator* iter) OVERRIDE {
155    return IPC::ReadParam(m, iter, &data_set_);
156  }
157
158  virtual void Log(std::string* log) const OVERRIDE {
159    IPC::LogParam(data_set_, log);
160  }
161
162 protected:
163  std::set<PermissionDataType> data_set_;
164};
165
166}  // namespace extensions
167
168#endif  // EXTENSIONS_COMMON_PERMISSIONS_SET_DISJUNCTION_PERMISSION_H_
169