| // Copyright (c) 2017 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 "quiche/common/platform/api/quiche_hostname_utils.h" |
| |
| #include <string> |
| |
| #include "absl/strings/string_view.h" |
| #include "quiche/common/platform/api/quiche_googleurl.h" |
| #include "quiche/common/platform/api/quiche_logging.h" |
| |
| namespace quiche { |
| |
| // TODO(vasilvv): the functions below are forked from Chromium's |
| // net/base/url_util.h; those should be moved to googleurl. |
| namespace { |
| |
| std::string CanonicalizeHost(absl::string_view host, |
| url::CanonHostInfo* host_info) { |
| // Try to canonicalize the host. |
| const url::Component raw_host_component(0, static_cast<int>(host.length())); |
| std::string canon_host; |
| url::StdStringCanonOutput canon_host_output(&canon_host); |
| url::CanonicalizeHostVerbose(host.data(), raw_host_component, |
| &canon_host_output, host_info); |
| |
| if (host_info->out_host.is_nonempty() && |
| host_info->family != url::CanonHostInfo::BROKEN) { |
| // Success! Assert that there's no extra garbage. |
| canon_host_output.Complete(); |
| QUICHE_DCHECK_EQ(host_info->out_host.len, |
| static_cast<int>(canon_host.length())); |
| } else { |
| // Empty host, or canonicalization failed. We'll return empty. |
| canon_host.clear(); |
| } |
| |
| return canon_host; |
| } |
| |
| bool IsHostCharAlphanumeric(char c) { |
| // We can just check lowercase because uppercase characters have already been |
| // normalized. |
| return ((c >= 'a') && (c <= 'z')) || ((c >= '0') && (c <= '9')); |
| } |
| |
| bool IsCanonicalizedHostCompliant(const std::string& host) { |
| if (host.empty()) { |
| return false; |
| } |
| |
| bool in_component = false; |
| bool most_recent_component_started_alphanumeric = false; |
| |
| for (char c : host) { |
| if (!in_component) { |
| most_recent_component_started_alphanumeric = IsHostCharAlphanumeric(c); |
| if (!most_recent_component_started_alphanumeric && (c != '-') && |
| (c != '_')) { |
| return false; |
| } |
| in_component = true; |
| } else if (c == '.') { |
| in_component = false; |
| } else if (!IsHostCharAlphanumeric(c) && (c != '-') && (c != '_')) { |
| return false; |
| } |
| } |
| |
| return most_recent_component_started_alphanumeric; |
| } |
| |
| } // namespace |
| |
| // static |
| bool QuicheHostnameUtils::IsValidSNI(absl::string_view sni) { |
| // TODO(rtenneti): Support RFC2396 hostname. |
| // NOTE: Microsoft does NOT enforce this spec, so if we throw away hostnames |
| // based on the above spec, we may be losing some hostnames that windows |
| // would consider valid. By far the most common hostname character NOT |
| // accepted by the above spec is '_'. |
| url::CanonHostInfo host_info; |
| std::string canonicalized_host = CanonicalizeHost(sni, &host_info); |
| return !host_info.IsIPAddress() && |
| IsCanonicalizedHostCompliant(canonicalized_host); |
| } |
| |
| // static |
| std::string QuicheHostnameUtils::NormalizeHostname(absl::string_view hostname) { |
| url::CanonHostInfo host_info; |
| std::string host = CanonicalizeHost(hostname, &host_info); |
| |
| // Walk backwards over the string, stopping at the first trailing dot. |
| size_t host_end = host.length(); |
| while (host_end != 0 && host[host_end - 1] == '.') { |
| host_end--; |
| } |
| |
| // Erase the trailing dots. |
| if (host_end != host.length()) { |
| host.erase(host_end, host.length() - host_end); |
| } |
| |
| return host; |
| } |
| |
| } // namespace quiche |