components/autofill/core/browser/password_generator.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 "components/autofill/core/browser/password_generator.h"
   6
   7 #include <algorithm>
   8 #include <vector>
   9
  10 #include "base/basictypes.h"
  11 #include "base/rand_util.h"
  12 #include "base/strings/string_util.h"
  13 #include "third_party/fips181/fips181.h"
  14
  15 const int kMinUpper = 65;  // First upper case letter 'A'
  16 const int kMaxUpper = 90;  // Last upper case letter 'Z'
  17 const int kMinLower = 97;  // First lower case letter 'a'
  18 const int kMaxLower = 122; // Last lower case letter 'z'
  19 const int kMinDigit = 48;  // First digit '0'
  20 const int kMaxDigit = 57;  // Last digit '9'
  21 const int kMinPasswordLength = 4;
  22 const int kMaxPasswordLength = 15;
  23
  24 namespace {
  25
  26 // A helper function to get the length of the generated password from
  27 // |max_length| retrieved from input password field.
  28 int GetLengthFromHint(int max_length, int default_length) {
  29   if (max_length >= kMinPasswordLength && max_length <= kMaxPasswordLength)
  30     return max_length;
  31   else
  32     return default_length;
  33 }
  34
  35 // We want the password to have uppercase, lowercase, and at least one number.
  36 bool VerifyPassword(const std::string& password) {
  37   int num_lower_case = 0;
  38   int num_upper_case = 0;
  39   int num_digits = 0;
  40
  41   for (size_t i = 0; i < password.size(); ++i) {
  42     if (password[i] >= kMinUpper && password[i] <= kMaxUpper)
  43       ++num_upper_case;
  44     if (password[i] >= kMinLower && password[i] <= kMaxLower)
  45       ++num_lower_case;
  46     if (password[i] >= kMinDigit && password[i] <= kMaxDigit)
  47       ++num_digits;
  48   }
  49
  50   return num_lower_case && num_upper_case && num_digits;
  51 }
  52
  53 // Make sure that there is at least one upper case and one number in the
  54 // password. Assume that there already exists a lower case letter as it's the
  55 // default from gen_pron_pass.
  56 void ForceFixPassword(std::string* password) {
  57   for (std::string::iterator iter = password->begin();
  58        iter != password->end(); ++iter) {
  59     if (islower(*iter)) {
  60       *iter = base::ToUpperASCII(*iter);
  61       break;
  62     }
  63   }
  64   for (std::string::reverse_iterator iter = password->rbegin();
  65        iter != password->rend(); ++iter) {
  66     if (islower(*iter)) {
  67       *iter = base::RandInt(kMinDigit, kMaxDigit);
  68       break;
  69     }
  70   }
  71 }
  72
  73 }  // namespace
  74
  75 namespace autofill {
  76
  77 const int PasswordGenerator::kDefaultPasswordLength = 12;
  78
  79 PasswordGenerator::PasswordGenerator(int max_length)
  80     : password_length_(GetLengthFromHint(max_length, kDefaultPasswordLength)) {}
  81 PasswordGenerator::~PasswordGenerator() {}
  82
  83 std::string PasswordGenerator::Generate() const {
  84   char password[255];
  85   char unused_hypenated_password[255];
  86   // Generate passwords that have numbers and upper and lower case letters.
  87   // No special characters included for now.
  88   unsigned int mode = S_NB | S_CL | S_SL;
  89
  90   // gen_pron_pass() doesn't guarantee that it includes all of the type given
  91   // in mode, so regenerate a few times if neccessary.
  92   // TODO(gcasto): Is it worth regenerating at all?
  93   for (int i = 0; i < 10; ++i) {
  94     gen_pron_pass(password, unused_hypenated_password,
  95                   password_length_, password_length_, mode);
  96     if (VerifyPassword(password))
  97       return std::string(password);
  98   }
  99
 100   // If the password still isn't conforming after a few iterations, force it
 101   // to be so. This may change a syllable in the password.
 102   std::string str_password(password);
 103   if (!VerifyPassword(str_password)) {
 104     ForceFixPassword(&str_password);
 105   }
 106   return str_password;
 107 }
 108
 109 }  // namespace autofill