components/proximity_auth/cryptauth/base64url.cc

   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 #include "components/proximity_auth/cryptauth/base64url.h"
   6
   7 #include "base/base64.h"
   8 #include "base/strings/string_util.h"
   9
  10 namespace proximity_auth {
  11
  12 void Base64UrlEncode(const std::string& decoded_input,
  13                      std::string* encoded_output) {
  14   base::Base64Encode(decoded_input, encoded_output);
  15   base::ReplaceChars(*encoded_output, "+", "-", encoded_output);
  16   base::ReplaceChars(*encoded_output, "/", "_", encoded_output);
  17 }
  18
  19 bool Base64UrlDecode(const std::string& encoded_input,
  20                      std::string* decoded_output) {
  21   // Bail on malformed strings, which already contain a '+' or a '/'. All valid
  22   // strings should escape these special characters as '-' and '_',
  23   // respectively.
  24   if (encoded_input.find_first_of("+/") != std::string::npos)
  25     return false;
  26
  27   std::string adjusted_encoded_input = encoded_input;
  28   base::ReplaceChars(adjusted_encoded_input, "-", "+", &adjusted_encoded_input);
  29   base::ReplaceChars(adjusted_encoded_input, "_", "/", &adjusted_encoded_input);
  30
  31   return base::Base64Decode(adjusted_encoded_input, decoded_output);
  32 }
  33
  34 }  // namespace proximity_auth