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 NET_DNS_DNS_CONFIG_SERVICE_WIN_H_
6#define NET_DNS_DNS_CONFIG_SERVICE_WIN_H_
7
8// The sole purpose of dns_config_service_win.h is for unittests so we just
9// include these headers here.
10#include <winsock2.h>
11#include <iphlpapi.h>
12
13#include <string>
14#include <vector>
15
16#include "base/memory/ref_counted.h"
17#include "base/memory/scoped_ptr.h"
18#include "base/strings/string16.h"
19#include "net/base/net_export.h"
20#include "net/dns/dns_config_service.h"
21
22// The general effort of DnsConfigServiceWin is to configure |nameservers| and
23// |search| in DnsConfig. The settings are stored in the Windows registry, but
24// to simplify the task we use the IP Helper API wherever possible. That API
25// yields the complete and ordered |nameservers|, but to determine |search| we
26// need to use the registry. On Windows 7, WMI does return the correct |search|
27// but on earlier versions it is insufficient.
28//
29// Experimental evaluation of Windows behavior suggests that domain parsing is
30// naive. Domain suffixes in |search| are not validated until they are appended
31// to the resolved name. We attempt to replicate this behavior.
32
33namespace net {
34
35namespace internal {
36
37// Parses |value| as search list (comma-delimited list of domain names) from
38// a registry key and stores it in |out|. Returns true on success. Empty
39// entries (e.g., "chromium.org,,org") terminate the list. Non-ascii hostnames
40// are converted to punycode.
41bool NET_EXPORT_PRIVATE ParseSearchList(const base::string16& value,
42                                        std::vector<std::string>* out);
43
44// All relevant settings read from registry and IP Helper. This isolates our
45// logic from system calls and is exposed for unit tests. Keep it an aggregate
46// struct for easy initialization.
47struct NET_EXPORT_PRIVATE DnsSystemSettings {
48  // The |set| flag distinguishes between empty and unset values.
49  struct RegString {
50    bool set;
51    base::string16 value;
52  };
53
54  struct RegDword {
55    bool set;
56    DWORD value;
57  };
58
59  struct DevolutionSetting {
60    // UseDomainNameDevolution
61    RegDword enabled;
62    // DomainNameDevolutionLevel
63    RegDword level;
64  };
65
66  // Filled in by GetAdapterAddresses. Note that the alternative
67  // GetNetworkParams does not include IPv6 addresses.
68  scoped_ptr<IP_ADAPTER_ADDRESSES, base::FreeDeleter> addresses;
69
70  // SOFTWARE\Policies\Microsoft\Windows NT\DNSClient\SearchList
71  RegString policy_search_list;
72  // SYSTEM\CurrentControlSet\Tcpip\Parameters\SearchList
73  RegString tcpip_search_list;
74  // SYSTEM\CurrentControlSet\Tcpip\Parameters\Domain
75  RegString tcpip_domain;
76  // SOFTWARE\Policies\Microsoft\System\DNSClient\PrimaryDnsSuffix
77  RegString primary_dns_suffix;
78
79  // SOFTWARE\Policies\Microsoft\Windows NT\DNSClient
80  DevolutionSetting policy_devolution;
81  // SYSTEM\CurrentControlSet\Dnscache\Parameters
82  DevolutionSetting dnscache_devolution;
83  // SYSTEM\CurrentControlSet\Tcpip\Parameters
84  DevolutionSetting tcpip_devolution;
85
86  // SOFTWARE\Policies\Microsoft\Windows NT\DNSClient\AppendToMultiLabelName
87  RegDword append_to_multi_label_name;
88
89  // True when the Name Resolution Policy Table (NRPT) has at least one rule:
90  // SOFTWARE\Policies\Microsoft\Windows NT\DNSClient\DnsPolicyConfig\Rule*
91  bool have_name_resolution_policy;
92};
93
94enum ConfigParseWinResult {
95  CONFIG_PARSE_WIN_OK = 0,
96  CONFIG_PARSE_WIN_READ_IPHELPER,
97  CONFIG_PARSE_WIN_READ_POLICY_SEARCHLIST,
98  CONFIG_PARSE_WIN_READ_TCPIP_SEARCHLIST,
99  CONFIG_PARSE_WIN_READ_DOMAIN,
100  CONFIG_PARSE_WIN_READ_POLICY_DEVOLUTION,
101  CONFIG_PARSE_WIN_READ_DNSCACHE_DEVOLUTION,
102  CONFIG_PARSE_WIN_READ_TCPIP_DEVOLUTION,
103  CONFIG_PARSE_WIN_READ_APPEND_MULTILABEL,
104  CONFIG_PARSE_WIN_READ_PRIMARY_SUFFIX,
105  CONFIG_PARSE_WIN_BAD_ADDRESS,
106  CONFIG_PARSE_WIN_NO_NAMESERVERS,
107  CONFIG_PARSE_WIN_UNHANDLED_OPTIONS,
108  CONFIG_PARSE_WIN_MAX  // Bounding values for enumeration.
109};
110
111// Fills in |dns_config| from |settings|. Exposed for tests.
112ConfigParseWinResult NET_EXPORT_PRIVATE ConvertSettingsToDnsConfig(
113    const DnsSystemSettings& settings,
114    DnsConfig* dns_config);
115
116// Use DnsConfigService::CreateSystemService to use it outside of tests.
117class NET_EXPORT_PRIVATE DnsConfigServiceWin : public DnsConfigService {
118 public:
119  DnsConfigServiceWin();
120  virtual ~DnsConfigServiceWin();
121
122 private:
123  class Watcher;
124  class ConfigReader;
125  class HostsReader;
126
127  // DnsConfigService:
128  virtual void ReadNow() OVERRIDE;
129  virtual bool StartWatching() OVERRIDE;
130
131  void OnConfigChanged(bool succeeded);
132  void OnHostsChanged(bool succeeded);
133
134  scoped_ptr<Watcher> watcher_;
135  scoped_refptr<ConfigReader> config_reader_;
136  scoped_refptr<HostsReader> hosts_reader_;
137
138  DISALLOW_COPY_AND_ASSIGN(DnsConfigServiceWin);
139};
140
141}  // namespace internal
142
143}  // namespace net
144
145#endif  // NET_DNS_DNS_CONFIG_SERVICE_WIN_H_
146
147