chrome/browser/install_verification/win/module_ids.cc

   1 // Copyright 2013 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 "chrome/browser/install_verification/win/module_ids.h"
   6
   7 #include <utility>
   8
   9 #include "base/basictypes.h"
  10 #include "base/logging.h"
  11 #include "base/strings/string_number_conversions.h"
  12 #include "base/strings/string_piece.h"
  13 #include "base/strings/string_tokenizer.h"
  14 #include "base/strings/string_util.h"
  15 #include "grit/browser_resources.h"
  16 #include "ui/base/resource/resource_bundle.h"
  17
  18 namespace {
  19
  20 struct { size_t id; const char* module_name_digest; }
  21   kExpectedInstallModules[] = {
  22     {1u, "c8cc47613e155f2129f480c6ced84549"},  // chrome.dll
  23     {2u, "49b78a23b0d8d5d8fb60d4e472b22764"},  // chrome_child.dll
  24   };
  25
  26 // Parses a line consisting of a positive decimal number and a 32-digit
  27 // hexadecimal number, separated by a space. Inserts the output, if valid, into
  28 // |module_ids|. Unexpected leading or trailing characters will cause
  29 // the line to be ignored, as will invalid decimal/hexadecimal characters.
  30 void ParseAdditionalModuleID(
  31     const base::StringPiece& line,
  32     ModuleIDs* module_ids) {
  33   DCHECK(module_ids);
  34
  35   base::CStringTokenizer line_tokenizer(line.begin(), line.end(), " ");
  36
  37   if (!line_tokenizer.GetNext())
  38     return;  // Empty string.
  39   base::StringPiece id_piece(line_tokenizer.token_piece());
  40
  41   if (!line_tokenizer.GetNext())
  42     return;  // No delimiter (' ').
  43   base::StringPiece digest_piece(line_tokenizer.token_piece());
  44
  45   if (line_tokenizer.GetNext())
  46     return;  // Unexpected trailing characters.
  47
  48   unsigned id = 0;
  49   if (!StringToUint(id_piece, &id))
  50     return;  // First token was not decimal.
  51
  52   if (digest_piece.length() != 32)
  53     return;  // Second token is not the right length.
  54
  55   for (base::StringPiece::const_iterator it = digest_piece.begin();
  56        it != digest_piece.end(); ++it) {
  57     if (!IsHexDigit(*it))
  58       return;  // Second token has invalid characters.
  59   }
  60
  61   // This is a valid line.
  62   module_ids->insert(std::make_pair(digest_piece.as_string(), id));
  63 }
  64
  65 }  // namespace
  66
  67 void ParseAdditionalModuleIDs(
  68     const base::StringPiece& raw_data,
  69     ModuleIDs* module_ids) {
  70   DCHECK(module_ids);
  71
  72   base::CStringTokenizer file_tokenizer(raw_data.begin(),
  73                                         raw_data.end(),
  74                                         "\r\n");
  75   while (file_tokenizer.GetNext()) {
  76     ParseAdditionalModuleID(base::StringPiece(file_tokenizer.token_piece()),
  77                             module_ids);
  78   }
  79 }
  80
  81 void LoadModuleIDs(ModuleIDs* module_ids) {
  82   for (size_t i = 0; i < arraysize(kExpectedInstallModules); ++i) {
  83     module_ids->insert(
  84         std::make_pair(
  85             kExpectedInstallModules[i].module_name_digest,
  86             kExpectedInstallModules[i].id));
  87   }
  88   ParseAdditionalModuleIDs(
  89       ResourceBundle::GetSharedInstance().GetRawDataResource(
  90           IDR_ADDITIONAL_MODULE_IDS),
  91       module_ids);
  92 }