Move each permission classes to its own files in extensions/permissions

chrome/common/extensions/permissions/permission_set.cc

+// Copyright (c) 2012 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 "chrome/common/extensions/permissions/permission_set.h"
+
+#include <algorithm>
+#include <string>
+
+#include "chrome/common/extensions/extension.h"
+#include "chrome/common/extensions/permissions/permissions_info.h"
+#include "chrome/common/extensions/url_pattern.h"
+#include "chrome/common/extensions/url_pattern_set.h"
+#include "content/public/common/url_constants.h"
+#include "grit/generated_resources.h"
+#include "net/base/registry_controlled_domain.h"
+#include "ui/base/l10n/l10n_util.h"
+
+namespace {
+
+// Helper for GetDistinctHosts(): com > net > org > everything else.
+bool RcdBetterThan(std::string a, std::string b) {
+  if (a == b)
+    return false;
+  if (a == "com")
+    return true;
+  if (a == "net")
+    return b != "com";
+  if (a == "org")
+    return b != "com" && b != "net";
+  return false;
+}
+
+// Names of API modules that can be used without listing it in the
+// permissions section of the manifest.
+const char* kNonPermissionModuleNames[] = {
+  "app",
+  "appWindow",
+  "browserAction",
+  "devtools",
+  "events",
+  "extension",
+  "i18n",
+  "omnibox",
+  "pageAction",
+  "pageActions",
+  "permissions",
+  "runtime",
+  "test",
+  "types"
+};
+const size_t kNumNonPermissionModuleNames =
+    arraysize(kNonPermissionModuleNames);
+
+// Names of functions (within modules requiring permissions) that can be used
+// without asking for the module permission. In other words, functions you can
+// use with no permissions specified.
+const char* kNonPermissionFunctionNames[] = {
+  "management.getPermissionWarningsByManifest",
+  "tabs.create",
+  "tabs.onRemoved",
+  "tabs.remove",
+  "tabs.update",
+};
+const size_t kNumNonPermissionFunctionNames =
+    arraysize(kNonPermissionFunctionNames);
+
+void AddPatternsAndRemovePaths(const URLPatternSet& set, URLPatternSet* out) {
+  DCHECK(out);
+  for (URLPatternSet::const_iterator i = set.begin(); i != set.end(); ++i) {
+    URLPattern p = *i;
+    p.SetPath("/*");
+    out->AddPattern(p);
+  }
+}
+
+// Strips out the API name from a function or event name.
+// Functions will be of the form api_name.function
+// Events will be of the form api_name/id or api_name.optional.stuff
+std::string GetPermissionName(const std::string& function_name) {
+  size_t separator = function_name.find_first_of("./");
+  if (separator != std::string::npos)
+    return function_name.substr(0, separator);
+  else
+    return function_name;
+}
+
+}  // namespace
+
+namespace extensions {
+
+//
+// PermissionSet
+//
+
+PermissionSet::PermissionSet() {}
+
+PermissionSet::PermissionSet(
+    const extensions::Extension* extension,
+    const APIPermissionSet& apis,
+    const URLPatternSet& explicit_hosts,
+    const OAuth2Scopes& scopes)
+    : apis_(apis),
+      scopes_(scopes) {
+  DCHECK(extension);
+  AddPatternsAndRemovePaths(explicit_hosts, &explicit_hosts_);
+  InitImplicitExtensionPermissions(extension);
+  InitEffectiveHosts();
+}
+
+PermissionSet::PermissionSet(
+    const APIPermissionSet& apis,
+    const URLPatternSet& explicit_hosts,
+    const URLPatternSet& scriptable_hosts)
+    : apis_(apis),
+      scriptable_hosts_(scriptable_hosts) {
+  AddPatternsAndRemovePaths(explicit_hosts, &explicit_hosts_);
+  InitEffectiveHosts();
+}
+
+PermissionSet::PermissionSet(
+    const APIPermissionSet& apis,
+    const URLPatternSet& explicit_hosts,
+    const URLPatternSet& scriptable_hosts,
+    const OAuth2Scopes& scopes)
+    : apis_(apis),
+      scriptable_hosts_(scriptable_hosts),
+      scopes_(scopes) {
+  AddPatternsAndRemovePaths(explicit_hosts, &explicit_hosts_);
+  InitEffectiveHosts();
+}
+
+PermissionSet::PermissionSet(
+    const OAuth2Scopes& scopes)
+    : scopes_(scopes) {
+  InitEffectiveHosts();
+}
+
+// static
+PermissionSet* PermissionSet::CreateDifference(
+    const PermissionSet* set1,
+    const PermissionSet* set2) {
+  scoped_refptr<PermissionSet> empty = new PermissionSet();
+  const PermissionSet* set1_safe = (set1 == NULL) ? empty : set1;
+  const PermissionSet* set2_safe = (set2 == NULL) ? empty : set2;
+
+  APIPermissionSet apis;
+  std::set_difference(set1_safe->apis().begin(), set1_safe->apis().end(),
+                      set2_safe->apis().begin(), set2_safe->apis().end(),
+                      std::insert_iterator<APIPermissionSet>(
+                          apis, apis.begin()));
+
+  URLPatternSet explicit_hosts;
+  URLPatternSet::CreateDifference(set1_safe->explicit_hosts(),
+                                  set2_safe->explicit_hosts(),
+                                  &explicit_hosts);
+
+  URLPatternSet scriptable_hosts;
+  URLPatternSet::CreateDifference(set1_safe->scriptable_hosts(),
+                                  set2_safe->scriptable_hosts(),
+                                  &scriptable_hosts);
+
+  OAuth2Scopes scopes;
+  std::set_difference(set1_safe->scopes().begin(), set1_safe->scopes().end(),
+                      set2_safe->scopes().begin(), set2_safe->scopes().end(),
+                      std::insert_iterator<OAuth2Scopes>(
+                          scopes, scopes.begin()));
+
+  return new PermissionSet(
+      apis, explicit_hosts, scriptable_hosts, scopes);
+}
+
+// static
+PermissionSet* PermissionSet::CreateIntersection(
+    const PermissionSet* set1,
+    const PermissionSet* set2) {
+  scoped_refptr<PermissionSet> empty = new PermissionSet();
+  const PermissionSet* set1_safe = (set1 == NULL) ? empty : set1;
+  const PermissionSet* set2_safe = (set2 == NULL) ? empty : set2;
+
+  APIPermissionSet apis;
+  std::set_intersection(set1_safe->apis().begin(), set1_safe->apis().end(),
+                        set2_safe->apis().begin(), set2_safe->apis().end(),
+                        std::insert_iterator<APIPermissionSet>(
+                            apis, apis.begin()));
+  URLPatternSet explicit_hosts;
+  URLPatternSet::CreateIntersection(set1_safe->explicit_hosts(),
+                                    set2_safe->explicit_hosts(),
+                                    &explicit_hosts);
+
+  URLPatternSet scriptable_hosts;
+  URLPatternSet::CreateIntersection(set1_safe->scriptable_hosts(),
+                                    set2_safe->scriptable_hosts(),
+                                    &scriptable_hosts);
+
+  OAuth2Scopes scopes;
+  std::set_intersection(set1_safe->scopes().begin(), set1_safe->scopes().end(),
+                        set2_safe->scopes().begin(), set2_safe->scopes().end(),
+                        std::insert_iterator<OAuth2Scopes>(
+                            scopes, scopes.begin()));
+
+  return new PermissionSet(
+      apis, explicit_hosts, scriptable_hosts, scopes);
+}
+
+// static
+PermissionSet* PermissionSet::CreateUnion(
+    const PermissionSet* set1,
+    const PermissionSet* set2) {
+  scoped_refptr<PermissionSet> empty = new PermissionSet();
+  const PermissionSet* set1_safe = (set1 == NULL) ? empty : set1;
+  const PermissionSet* set2_safe = (set2 == NULL) ? empty : set2;
+
+  APIPermissionSet apis;
+  std::set_union(set1_safe->apis().begin(), set1_safe->apis().end(),
+                 set2_safe->apis().begin(), set2_safe->apis().end(),
+                 std::insert_iterator<APIPermissionSet>(
+                     apis, apis.begin()));
+
+  URLPatternSet explicit_hosts;
+  URLPatternSet::CreateUnion(set1_safe->explicit_hosts(),
+                             set2_safe->explicit_hosts(),
+                             &explicit_hosts);
+
+  URLPatternSet scriptable_hosts;
+  URLPatternSet::CreateUnion(set1_safe->scriptable_hosts(),
+                             set2_safe->scriptable_hosts(),
+                             &scriptable_hosts);
+
+  OAuth2Scopes scopes;
+  std::set_union(set1_safe->scopes().begin(), set1_safe->scopes().end(),
+                 set2_safe->scopes().begin(), set2_safe->scopes().end(),
+                 std::insert_iterator<OAuth2Scopes>(
+                     scopes, scopes.begin()));
+
+  return new PermissionSet(
+      apis, explicit_hosts, scriptable_hosts, scopes);
+}
+
+bool PermissionSet::operator==(
+    const PermissionSet& rhs) const {
+  return apis_ == rhs.apis_ &&
+      scriptable_hosts_ == rhs.scriptable_hosts_ &&
+      explicit_hosts_ == rhs.explicit_hosts_ &&
+      scopes_ == rhs.scopes_;
+}
+
+bool PermissionSet::Contains(const PermissionSet& set) const {
+  // Every set includes the empty set.
+  if (set.IsEmpty())
+    return true;
+
+  if (!std::includes(apis_.begin(), apis_.end(),
+                     set.apis().begin(), set.apis().end()))
+    return false;
+
+  if (!explicit_hosts().Contains(set.explicit_hosts()))
+    return false;
+
+  if (!scriptable_hosts().Contains(set.scriptable_hosts()))
+    return false;
+
+  if (!std::includes(scopes_.begin(), scopes_.end(),
+                     set.scopes().begin(), set.scopes().end()))
+    return false;
+
+  return true;
+}
+
+std::set<std::string> PermissionSet::GetAPIsAsStrings() const {
+  PermissionsInfo* info = PermissionsInfo::GetInstance();
+  std::set<std::string> apis_str;
+  for (APIPermissionSet::const_iterator i = apis_.begin();
+       i != apis_.end(); ++i) {
+    APIPermission* permission = info->GetByID(*i);
+    if (permission)
+      apis_str.insert(permission->name());
+  }
+  return apis_str;
+}
+
+std::set<std::string> PermissionSet::
+    GetAPIsWithAnyAccessAsStrings() const {
+  std::set<std::string> result = GetAPIsAsStrings();
+  for (size_t i = 0; i < kNumNonPermissionModuleNames; ++i)
+    result.insert(kNonPermissionModuleNames[i]);
+  for (size_t i = 0; i < kNumNonPermissionFunctionNames; ++i)
+    result.insert(GetPermissionName(kNonPermissionFunctionNames[i]));
+  return result;
+}
+
+bool PermissionSet::HasAnyAccessToAPI(
+    const std::string& api_name) const {
+  if (HasAccessToFunction(api_name))
+    return true;
+
+  for (size_t i = 0; i < kNumNonPermissionFunctionNames; ++i) {
+    if (api_name == GetPermissionName(kNonPermissionFunctionNames[i]))
+      return true;
+  }
+
+  return false;
+}
+
+std::set<std::string>
+    PermissionSet::GetDistinctHostsForDisplay() const {
+  return GetDistinctHosts(effective_hosts_, true, true);
+}
+
+PermissionMessages
+    PermissionSet::GetPermissionMessages() const {
+  PermissionMessages messages;
+
+  if (HasEffectiveFullAccess()) {
+    messages.push_back(PermissionMessage(
+        PermissionMessage::kFullAccess,
+        l10n_util::GetStringUTF16(IDS_EXTENSION_PROMPT_WARNING_FULL_ACCESS)));
+    return messages;
+  }
+
+  if (HasEffectiveAccessToAllHosts()) {
+    messages.push_back(PermissionMessage(
+        PermissionMessage::kHostsAll,
+        l10n_util::GetStringUTF16(IDS_EXTENSION_PROMPT_WARNING_ALL_HOSTS)));
+  } else {
+    std::set<std::string> hosts = GetDistinctHostsForDisplay();
+    if (!hosts.empty())
+      messages.push_back(PermissionMessage::CreateFromHostList(hosts));
+  }
+
+  std::set<PermissionMessage> simple_msgs =
+      GetSimplePermissionMessages();
+  messages.insert(messages.end(), simple_msgs.begin(), simple_msgs.end());
+
+  return messages;
+}
+
+std::vector<string16> PermissionSet::GetWarningMessages() const {
+  std::vector<string16> messages;
+  PermissionMessages permissions = GetPermissionMessages();
+
+  bool audio_capture = false;
+  bool video_capture = false;
+  for (PermissionMessages::const_iterator i = permissions.begin();
+       i != permissions.end(); ++i) {
+    if (i->id() == PermissionMessage::kAudioCapture)
+      audio_capture = true;
+    if (i->id() == PermissionMessage::kVideoCapture)
+      video_capture = true;
+  }
+
+  for (PermissionMessages::const_iterator i = permissions.begin();
+       i != permissions.end(); ++i) {
+    if (audio_capture && video_capture) {
+      if (i->id() == PermissionMessage::kAudioCapture) {
+        messages.push_back(l10n_util::GetStringUTF16(
+            IDS_EXTENSION_PROMPT_WARNING_AUDIO_AND_VIDEO_CAPTURE));
+        continue;
+      } else if (i->id() == PermissionMessage::kVideoCapture) {
+        // The combined message will be pushed above.
+        continue;
+      }
+    }
+
+    messages.push_back(i->message());
+  }
+
+  return messages;
+}
+
+bool PermissionSet::IsEmpty() const {
+  // Not default if any host permissions are present.
+  if (!(explicit_hosts().is_empty() && scriptable_hosts().is_empty()))
+    return false;
+
+  // Or if it has no api permissions.
+  return apis().empty();
+}
+
+bool PermissionSet::HasAPIPermission(
+    APIPermission::ID permission) const {
+  return apis().find(permission) != apis().end();
+}
+
+bool PermissionSet::HasAccessToFunction(
+    const std::string& function_name) const {
+  // TODO(jstritar): Embed this information in each permission and add a method
+  // like GrantsAccess(function_name) to APIPermission. A "default"
+  // permission can then handle the modules and functions that everyone can
+  // access.
+  for (size_t i = 0; i < kNumNonPermissionFunctionNames; ++i) {
+    if (function_name == kNonPermissionFunctionNames[i])
+      return true;
+  }
+
+  std::string permission_name = GetPermissionName(function_name);
+  APIPermission* permission =
+      PermissionsInfo::GetInstance()->GetByName(permission_name);
+  if (permission && apis_.count(permission->id()))
+    return true;
+
+  for (size_t i = 0; i < kNumNonPermissionModuleNames; ++i) {
+    if (permission_name == kNonPermissionModuleNames[i]) {
+      return true;
+    }
+  }
+
+  return false;
+}
+
+bool PermissionSet::HasExplicitAccessToOrigin(
+    const GURL& origin) const {
+  return explicit_hosts().MatchesURL(origin);
+}
+
+bool PermissionSet::HasScriptableAccessToURL(
+    const GURL& origin) const {
+  // We only need to check our host list to verify access. The host list should
+  // already reflect any special rules (such as chrome://favicon, all hosts
+  // access, etc.).
+  return scriptable_hosts().MatchesURL(origin);
+}
+
+bool PermissionSet::HasEffectiveAccessToAllHosts() const {
+  // There are two ways this set can have effective access to all hosts:
+  //  1) it has an <all_urls> URL pattern.
+  //  2) it has a named permission with implied full URL access.
+  for (URLPatternSet::const_iterator host = effective_hosts().begin();
+       host != effective_hosts().end(); ++host) {
+    if (host->match_all_urls() ||
+        (host->match_subdomains() && host->host().empty()))
+      return true;
+  }
+
+  PermissionsInfo* info = PermissionsInfo::GetInstance();
+  for (APIPermissionSet::const_iterator i = apis().begin();
+       i != apis().end(); ++i) {
+    APIPermission* permission = info->GetByID(*i);
+    if (permission->implies_full_url_access())
+      return true;
+  }
+  return false;
+}
+
+bool PermissionSet::HasEffectiveAccessToURL(
+    const GURL& url) const {
+  return effective_hosts().MatchesURL(url);
+}
+
+bool PermissionSet::HasEffectiveFullAccess() const {
+  PermissionsInfo* info = PermissionsInfo::GetInstance();
+  for (APIPermissionSet::const_iterator i = apis().begin();
+       i != apis().end(); ++i) {
+    APIPermission* permission = info->GetByID(*i);
+    if (permission->implies_full_access())
+      return true;
+  }
+  return false;
+}
+
+bool PermissionSet::HasLessPrivilegesThan(
+    const PermissionSet* permissions) const {
+  // Things can't get worse than native code access.
+  if (HasEffectiveFullAccess())
+    return false;
+
+  // Otherwise, it's a privilege increase if the new one has full access.
+  if (permissions->HasEffectiveFullAccess())
+    return true;
+
+  if (HasLessHostPrivilegesThan(permissions))
+    return true;
+
+  if (HasLessAPIPrivilegesThan(permissions))
+    return true;
+
+  if (HasLessScopesThan(permissions))
+    return true;
+
+  return false;
+}
+
+PermissionSet::~PermissionSet() {}
+
+// static
+std::set<std::string> PermissionSet::GetDistinctHosts(
+    const URLPatternSet& host_patterns,
+    bool include_rcd,
+    bool exclude_file_scheme) {
+  // Use a vector to preserve order (also faster than a map on small sets).
+  // Each item is a host split into two parts: host without RCDs and
+  // current best RCD.
+  typedef std::vector<std::pair<std::string, std::string> > HostVector;
+  HostVector hosts_best_rcd;
+  for (URLPatternSet::const_iterator i = host_patterns.begin();
+       i != host_patterns.end(); ++i) {
+    if (exclude_file_scheme && i->scheme() == chrome::kFileScheme)
+      continue;
+
+    std::string host = i->host();
+
+    // Add the subdomain wildcard back to the host, if necessary.
+    if (i->match_subdomains())
+      host = "*." + host;
+
+    // If the host has an RCD, split it off so we can detect duplicates.
+    std::string rcd;
+    size_t reg_len = net::RegistryControlledDomainService::GetRegistryLength(
+        host, false);
+    if (reg_len && reg_len != std::string::npos) {
+      if (include_rcd)  // else leave rcd empty
+        rcd = host.substr(host.size() - reg_len);
+      host = host.substr(0, host.size() - reg_len);
+    }
+
+    // Check if we've already seen this host.
+    HostVector::iterator it = hosts_best_rcd.begin();
+    for (; it != hosts_best_rcd.end(); ++it) {
+      if (it->first == host)
+        break;
+    }
+    // If this host was found, replace the RCD if this one is better.
+    if (it != hosts_best_rcd.end()) {
+      if (include_rcd && RcdBetterThan(rcd, it->second))
+        it->second = rcd;
+    } else {  // Previously unseen host, append it.
+      hosts_best_rcd.push_back(std::make_pair(host, rcd));
+    }
+  }
+
+  // Build up the final vector by concatenating hosts and RCDs.
+  std::set<std::string> distinct_hosts;
+  for (HostVector::iterator it = hosts_best_rcd.begin();
+       it != hosts_best_rcd.end(); ++it)
+    distinct_hosts.insert(it->first + it->second);
+  return distinct_hosts;
+}
+
+void PermissionSet::InitImplicitExtensionPermissions(
+    const extensions::Extension* extension) {
+  // Add the implied permissions.
+  if (!extension->plugins().empty())
+    apis_.insert(APIPermission::kPlugin);
+
+  if (!extension->devtools_url().is_empty())
+    apis_.insert(APIPermission::kDevtools);
+
+  // The webRequest permission implies the internal version as well.
+  if (apis_.find(APIPermission::kWebRequest) != apis_.end())
+    apis_.insert(APIPermission::kWebRequestInternal);
+
+  // The fileBrowserHandler permission implies the internal version as well.
+  if (apis_.find(APIPermission::kFileBrowserHandler) != apis_.end())
+    apis_.insert(APIPermission::kFileBrowserHandlerInternal);
+
+  // Add the scriptable hosts.
+  for (UserScriptList::const_iterator content_script =
+           extension->content_scripts().begin();
+       content_script != extension->content_scripts().end(); ++content_script) {
+    URLPatternSet::const_iterator pattern =
+        content_script->url_patterns().begin();
+    for (; pattern != content_script->url_patterns().end(); ++pattern)
+      scriptable_hosts_.AddPattern(*pattern);
+  }
+}
+
+void PermissionSet::InitEffectiveHosts() {
+  effective_hosts_.ClearPatterns();
+
+  URLPatternSet::CreateUnion(
+      explicit_hosts(), scriptable_hosts(), &effective_hosts_);
+}
+
+std::set<PermissionMessage>
+    PermissionSet::GetSimplePermissionMessages() const {
+  std::set<PermissionMessage> messages;
+  PermissionsInfo* info = PermissionsInfo::GetInstance();
+  for (APIPermissionSet::const_iterator i = apis_.begin();
+       i != apis_.end(); ++i) {
+    DCHECK_GT(PermissionMessage::kNone,
+              PermissionMessage::kUnknown);
+    APIPermission* perm = info->GetByID(*i);
+    if (perm && perm->message_id() > PermissionMessage::kNone)
+      messages.insert(perm->GetMessage());
+  }
+  return messages;
+}
+
+bool PermissionSet::HasLessAPIPrivilegesThan(
+    const PermissionSet* permissions) const {
+  if (permissions == NULL)
+    return false;
+
+  std::set<PermissionMessage> current_warnings =
+      GetSimplePermissionMessages();
+  std::set<PermissionMessage> new_warnings =
+      permissions->GetSimplePermissionMessages();
+  std::set<PermissionMessage> delta_warnings;
+  std::set_difference(new_warnings.begin(), new_warnings.end(),
+                      current_warnings.begin(), current_warnings.end(),
+                      std::inserter(delta_warnings, delta_warnings.begin()));
+
+  // We have less privileges if there are additional warnings present.
+  return !delta_warnings.empty();
+}
+
+bool PermissionSet::HasLessHostPrivilegesThan(
+    const PermissionSet* permissions) const {
+  // If this permission set can access any host, then it can't be elevated.
+  if (HasEffectiveAccessToAllHosts())
+    return false;
+
+  // Likewise, if the other permission set has full host access, then it must be
+  // a privilege increase.
+  if (permissions->HasEffectiveAccessToAllHosts())
+    return true;
+
+  const URLPatternSet& old_list = effective_hosts();
+  const URLPatternSet& new_list = permissions->effective_hosts();
+
+  // TODO(jstritar): This is overly conservative with respect to subdomains.
+  // For example, going from *.google.com to www.google.com will be
+  // considered an elevation, even though it is not (http://crbug.com/65337).
+  std::set<std::string> new_hosts_set(GetDistinctHosts(new_list, false, false));
+  std::set<std::string> old_hosts_set(GetDistinctHosts(old_list, false, false));
+  std::set<std::string> new_hosts_only;
+
+  std::set_difference(new_hosts_set.begin(), new_hosts_set.end(),
+                      old_hosts_set.begin(), old_hosts_set.end(),
+                      std::inserter(new_hosts_only, new_hosts_only.begin()));
+
+  return !new_hosts_only.empty();
+}
+
+bool PermissionSet::HasLessScopesThan(
+    const PermissionSet* permissions) const {
+  if (permissions == NULL)
+    return false;
+
+  OAuth2Scopes current_scopes = scopes();
+  OAuth2Scopes new_scopes = permissions->scopes();
+  OAuth2Scopes delta_scopes;
+  std::set_difference(new_scopes.begin(), new_scopes.end(),
+                      current_scopes.begin(), current_scopes.end(),
+                      std::inserter(delta_scopes, delta_scopes.begin()));
+
+  // We have less privileges if there are additional scopes present.
+  return !delta_scopes.empty();
+}
+
+}  // namespace extensions