Split SdchManager::Dictionary out into separate class/file.

net/base/sdch_dictionary.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 "net/base/sdch_dictionary.h"
+
+#include "base/time/clock.h"
+#include "base/time/default_clock.h"
+#include "base/values.h"
+#include "net/base/registry_controlled_domains/registry_controlled_domain.h"
+
+namespace {
+
+bool DomainMatch(const GURL& gurl, const std::string& restriction) {
+  // TODO(jar): This is not precisely a domain match definition.
+  return gurl.DomainIs(restriction.data(), restriction.size());
+}
+
+}  // namespace
+
+namespace net {
+
+SdchDictionary::SdchDictionary(const std::string& dictionary_text,
+                               size_t offset,
+                               const std::string& client_hash,
+                               const std::string& server_hash,
+                               const GURL& gurl,
+                               const std::string& domain,
+                               const std::string& path,
+                               const base::Time& expiration,
+                               const std::set<int>& ports)
+    : text_(dictionary_text, offset),
+      client_hash_(client_hash),
+      server_hash_(server_hash),
+      url_(gurl),
+      domain_(domain),
+      path_(path),
+      expiration_(expiration),
+      ports_(ports),
+      clock_(new base::DefaultClock) {
+}
+
+SdchDictionary::SdchDictionary(const SdchDictionary& rhs)
+    : text_(rhs.text_),
+      client_hash_(rhs.client_hash_),
+      server_hash_(rhs.server_hash_),
+      url_(rhs.url_),
+      domain_(rhs.domain_),
+      path_(rhs.path_),
+      expiration_(rhs.expiration_),
+      ports_(rhs.ports_),
+      clock_(new base::DefaultClock) {
+}
+
+SdchDictionary::~SdchDictionary() {
+}
+
+// Security functions restricting loads and use of dictionaries.
+
+// static
+SdchProblemCode SdchDictionary::CanSet(const std::string& domain,
+                                       const std::string& path,
+                                       const std::set<int>& ports,
+                                       const GURL& dictionary_url) {
+  /*
+   * A dictionary is invalid and must not be stored if any of the following are
+   * true:
+   * 1. The dictionary has no Domain attribute.
+   * 2. The effective host name that derives from the referer URL host name does
+   *    not domain-match the Domain attribute.
+   * 3. The Domain attribute is a top level domain.
+   * 4. The referer URL host is a host domain name (not IP address) and has the
+   *    form HD, where D is the value of the Domain attribute, and H is a string
+   *    that contains one or more dots.
+   * 5. If the dictionary has a Port attribute and the referer URL's port
+   *    was not in the list.
+   */
+
+  // TODO(jar): Redirects in dictionary fetches might plausibly be problematic,
+  // and hence the conservative approach is to not allow any redirects (if there
+  // were any... then don't allow the dictionary to be set).
+
+  if (domain.empty())
+    return SDCH_DICTIONARY_MISSING_DOMAIN_SPECIFIER;  // Domain is required.
+
+  if (registry_controlled_domains::GetDomainAndRegistry(
+          domain, registry_controlled_domains::INCLUDE_PRIVATE_REGISTRIES)
+          .empty()) {
+    return SDCH_DICTIONARY_SPECIFIES_TOP_LEVEL_DOMAIN;  // domain was a TLD.
+  }
+
+  if (!DomainMatch(dictionary_url, domain))
+    return SDCH_DICTIONARY_DOMAIN_NOT_MATCHING_SOURCE_URL;
+
+  std::string referrer_url_host = dictionary_url.host();
+  size_t postfix_domain_index = referrer_url_host.rfind(domain);
+  // See if it is indeed a postfix, or just an internal string.
+  if (referrer_url_host.size() == postfix_domain_index + domain.size()) {
+    // It is a postfix... so check to see if there's a dot in the prefix.
+    size_t end_of_host_index = referrer_url_host.find_first_of('.');
+    if (referrer_url_host.npos != end_of_host_index &&
+        end_of_host_index < postfix_domain_index) {
+      return SDCH_DICTIONARY_REFERER_URL_HAS_DOT_IN_PREFIX;
+    }
+  }
+
+  if (!ports.empty() && 0 == ports.count(dictionary_url.EffectiveIntPort()))
+    return SDCH_DICTIONARY_PORT_NOT_MATCHING_SOURCE_URL;
+
+  return SDCH_OK;
+}
+
+SdchProblemCode SdchDictionary::CanUse(const GURL& target_url) const {
+  /*
+   * 1. The request URL's host name domain-matches the Domain attribute of the
+   *    dictionary.
+   * 2. If the dictionary has a Port attribute, the request port is one of the
+   *     ports listed in the Port attribute.
+   * 3. The request URL path-matches the path attribute of the dictionary.
+   *    We can override (ignore) item (4) only when we have explicitly enabled
+   *    HTTPS support AND the dictionary acquisition scheme matches the target
+   *   url scheme.
+   */
+  if (!DomainMatch(target_url, domain_))
+    return SDCH_DICTIONARY_FOUND_HAS_WRONG_DOMAIN;
+
+  if (!ports_.empty() && 0 == ports_.count(target_url.EffectiveIntPort()))
+    return SDCH_DICTIONARY_FOUND_HAS_WRONG_PORT_LIST;
+
+  if (path_.size() && !PathMatch(target_url.path(), path_))
+    return SDCH_DICTIONARY_FOUND_HAS_WRONG_PATH;
+
+  if (target_url.SchemeIsSecure() != url_.SchemeIsSecure())
+    return SDCH_DICTIONARY_FOUND_HAS_WRONG_SCHEME;
+
+  // TODO(jar): Remove overly restrictive failsafe test (added per security
+  // review) when we have a need to be more general.
+  if (!target_url.SchemeIsHTTPOrHTTPS())
+    return SDCH_ATTEMPT_TO_DECODE_NON_HTTP_DATA;
+
+  return SDCH_OK;
+}
+
+// static
+bool SdchDictionary::PathMatch(const std::string& path,
+                               const std::string& restriction) {
+  /*  Must be either:
+   *  1. P2 is equal to P1
+   *  2. P2 is a prefix of P1 and either the final character in P2 is "/"
+   *     or the character following P2 in P1 is "/".
+   */
+  if (path == restriction)
+    return true;
+  size_t prefix_length = restriction.size();
+  if (prefix_length > path.size())
+    return false;  // Can't be a prefix.
+  if (0 != path.compare(0, prefix_length, restriction))
+    return false;
+  return restriction[prefix_length - 1] == '/' || path[prefix_length] == '/';
+}
+
+bool SdchDictionary::Expired() const {
+  return clock_->Now() > expiration_;
+}
+
+void SdchDictionary::SetClockForTesting(scoped_ptr<base::Clock> clock) {
+  clock_ = clock.Pass();
+}
+
+}  // namespace net