network_util.cc revision 5d1f7b1de12d16ceb2c938c56701a3e8bfa558f7 
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#include "chromeos/network/network_util.h"
6
7#include "base/strings/string_tokenizer.h"
8#include "base/strings/stringprintf.h"
9#include "third_party/cros_system_api/dbus/service_constants.h"
10
11namespace chromeos {
12
13WifiAccessPoint::WifiAccessPoint()
14    : signal_strength(0),
15      signal_to_noise(0),
16      channel(0) {
17}
18
19WifiAccessPoint::~WifiAccessPoint() {
20}
21
22CellularScanResult::CellularScanResult() {
23}
24
25CellularScanResult::~CellularScanResult() {
26}
27
28namespace network_util {
29
30std::string PrefixLengthToNetmask(int32 prefix_length) {
31  std::string netmask;
32  // Return the empty string for invalid inputs.
33  if (prefix_length < 0 || prefix_length > 32)
34    return netmask;
35  for (int i = 0; i < 4; i++) {
36    int remainder = 8;
37    if (prefix_length >= 8) {
38      prefix_length -= 8;
39    } else {
40      remainder = prefix_length;
41      prefix_length = 0;
42    }
43    if (i > 0)
44      netmask += ".";
45    int value = remainder == 0 ? 0 :
46        ((2L << (remainder - 1)) - 1) << (8 - remainder);
47    netmask += base::StringPrintf("%d", value);
48  }
49  return netmask;
50}
51
52int32 NetmaskToPrefixLength(const std::string& netmask) {
53  int count = 0;
54  int prefix_length = 0;
55  base::StringTokenizer t(netmask, ".");
56  while (t.GetNext()) {
57    // If there are more than 4 numbers, then it's invalid.
58    if (count == 4)
59      return -1;
60
61    std::string token = t.token();
62    // If we already found the last mask and the current one is not
63    // "0" then the netmask is invalid. For example, 255.224.255.0
64    if (prefix_length / 8 != count) {
65      if (token != "0")
66        return -1;
67    } else if (token == "255") {
68      prefix_length += 8;
69    } else if (token == "254") {
70      prefix_length += 7;
71    } else if (token == "252") {
72      prefix_length += 6;
73    } else if (token == "248") {
74      prefix_length += 5;
75    } else if (token == "240") {
76      prefix_length += 4;
77    } else if (token == "224") {
78      prefix_length += 3;
79    } else if (token == "192") {
80      prefix_length += 2;
81    } else if (token == "128") {
82      prefix_length += 1;
83    } else if (token == "0") {
84      prefix_length += 0;
85    } else {
86      // mask is not a valid number.
87      return -1;
88    }
89    count++;
90  }
91  if (count < 4)
92    return -1;
93  return prefix_length;
94}
95
96bool ParseCellularScanResults(const base::ListValue& list,
97                              std::vector<CellularScanResult>* scan_results) {
98  scan_results->clear();
99  scan_results->reserve(list.GetSize());
100  for (base::ListValue::const_iterator it = list.begin();
101       it != list.end(); ++it) {
102    if (!(*it)->IsType(base::Value::TYPE_DICTIONARY))
103      return false;
104    CellularScanResult scan_result;
105    const base::DictionaryValue* dict =
106        static_cast<const base::DictionaryValue*>(*it);
107    // If the network id property is not present then this network cannot be
108    // connected to so don't include it in the results.
109    if (!dict->GetStringWithoutPathExpansion(shill::kNetworkIdProperty,
110                                             &scan_result.network_id))
111      continue;
112    dict->GetStringWithoutPathExpansion(shill::kStatusProperty,
113                                        &scan_result.status);
114    dict->GetStringWithoutPathExpansion(shill::kLongNameProperty,
115                                        &scan_result.long_name);
116    dict->GetStringWithoutPathExpansion(shill::kShortNameProperty,
117                                        &scan_result.short_name);
118    dict->GetStringWithoutPathExpansion(shill::kTechnologyProperty,
119                                        &scan_result.technology);
120    scan_results->push_back(scan_result);
121  }
122  return true;
123}
124
125}  // namespace network_util
126}  // namespace chromeos
127