Support Kerberos on Android

net/http/http_auth_multi_round_parse.cc

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/base64.h"
+#include "base/strings/string_util.h"
+#include "net/http/http_auth_challenge_tokenizer.h"
+#include "net/http/http_auth_multi_round_parse.h"
+
+namespace net {
+
+namespace {
+
+// Check that the scheme in the challenge matches the expected scheme
+bool SchemeIsValid(const std::string& scheme,
+                   HttpAuthChallengeTokenizer* challenge) {
+  // There is no guarantee that challenge->scheme() is valid ASCII, but
+  // LowerCaseEqualsASCII will do the right thing even if it isn't.
+  return base::LowerCaseEqualsASCII(challenge->scheme(),
+                                    base::StringToLowerASCII(scheme).c_str());
+}
+
+}  // namespace
+
+HttpAuth::AuthorizationResult ParseFirstRoundChallenge(
+    const std::string& scheme,
+    HttpAuthChallengeTokenizer* challenge) {
+  // Verify the challenge's auth-scheme.
+  if (!SchemeIsValid(scheme, challenge))
+    return HttpAuth::AUTHORIZATION_RESULT_INVALID;
+
+  std::string encoded_auth_token = challenge->base64_param();
+  if (!encoded_auth_token.empty()) {
+    return HttpAuth::AUTHORIZATION_RESULT_INVALID;
+  }
+  return HttpAuth::AUTHORIZATION_RESULT_ACCEPT;
+}
+
+HttpAuth::AuthorizationResult ParseLaterRoundChallenge(
+    const std::string& scheme,
+    HttpAuthChallengeTokenizer* challenge,
+    std::string* encoded_token,
+    std::string* decoded_token) {
+  // Verify the challenge's auth-scheme.
+  if (!SchemeIsValid(scheme, challenge))
+    return HttpAuth::AUTHORIZATION_RESULT_INVALID;
+
+  *encoded_token = challenge->base64_param();
+  if (encoded_token->empty())
+    return HttpAuth::AUTHORIZATION_RESULT_REJECT;
+
+  // Make sure the additional token is base64 encoded.
+  if (!base::Base64Decode(*encoded_token, decoded_token))
+    return HttpAuth::AUTHORIZATION_RESULT_INVALID;
+  return HttpAuth::AUTHORIZATION_RESULT_ACCEPT;
+}
+
+}  // namespace net