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 "net/http/http_auth_challenge_tokenizer.h"
6
7#include "base/strings/string_tokenizer.h"
8
9namespace net {
10
11HttpAuthChallengeTokenizer::HttpAuthChallengeTokenizer(
12    std::string::const_iterator begin,
13    std::string::const_iterator end)
14    : begin_(begin),
15      end_(end),
16      scheme_begin_(begin),
17      scheme_end_(begin),
18      params_begin_(end),
19      params_end_(end) {
20  Init(begin, end);
21}
22
23HttpUtil::NameValuePairsIterator HttpAuthChallengeTokenizer::param_pairs()
24    const {
25  return HttpUtil::NameValuePairsIterator(params_begin_, params_end_, ',');
26}
27
28std::string HttpAuthChallengeTokenizer::base64_param() const {
29  // Strip off any padding.
30  // (See https://bugzilla.mozilla.org/show_bug.cgi?id=230351.)
31  //
32  // Our base64 decoder requires that the length be a multiple of 4.
33  int encoded_length = params_end_ - params_begin_;
34  while (encoded_length > 0 && encoded_length % 4 != 0 &&
35         params_begin_[encoded_length - 1] == '=') {
36    --encoded_length;
37  }
38  return std::string(params_begin_, params_begin_ + encoded_length);
39}
40
41void HttpAuthChallengeTokenizer::Init(std::string::const_iterator begin,
42                                      std::string::const_iterator end) {
43  // The first space-separated token is the auth-scheme.
44  // NOTE: we are more permissive than RFC 2617 which says auth-scheme
45  // is separated by 1*SP.
46  base::StringTokenizer tok(begin, end, HTTP_LWS);
47  if (!tok.GetNext()) {
48    // Default param and scheme iterators provide empty strings
49    return;
50  }
51
52  // Save the scheme's position.
53  scheme_begin_ = tok.token_begin();
54  scheme_end_ = tok.token_end();
55
56  params_begin_ = scheme_end_;
57  params_end_ = end;
58  HttpUtil::TrimLWS(&params_begin_, &params_end_);
59}
60
61}  // namespace net
62