Move permission warning message handling from PermissionSet to PermissionMessageProvider.

chrome/common/extensions/permissions/chrome_permission_message_provider.cc

Index: chrome/common/extensions/permissions/chrome_permission_message_provider.cc
diff --git a/chrome/common/extensions/permissions/chrome_permission_message_provider.cc b/chrome/common/extensions/permissions/chrome_permission_message_provider.cc
new file mode 100644
index 0000000000000000000000000000000000000000..53f8700342a38df2a1a57711abfb76c4033bb03b
--- /dev/null
+++ b/chrome/common/extensions/permissions/chrome_permission_message_provider.cc
@@ -0,0 +1,261 @@
+// Copyright 2013 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/chrome_permission_message_provider.h"
+
+#include "base/stl_util.h"
+#include "chrome/common/extensions/permissions/permission_message_util.h"
+#include "chrome/common/extensions/permissions/permission_set.h"
+#include "extensions/common/extensions_client.h"
+#include "extensions/common/permissions/permission_message.h"
+#include "extensions/common/url_pattern_set.h"
+#include "grit/generated_resources.h"
+#include "ui/base/l10n/l10n_util.h"
+
+namespace extensions {
+
+ChromePermissionMessageProvider::ChromePermissionMessageProvider() {
+}
+
+ChromePermissionMessageProvider::~ChromePermissionMessageProvider() {
+}
+
+// static
+PermissionMessages ChromePermissionMessageProvider::GetPermissionMessages(
+    const PermissionSet* permissions,
+    Manifest::Type extension_type) const {
+  PermissionMessages messages;
+
+  if (permissions->HasEffectiveFullAccess()) {
+    messages.push_back(PermissionMessage(
+        PermissionMessage::kFullAccess,
+        l10n_util::GetStringUTF16(IDS_EXTENSION_PROMPT_WARNING_FULL_ACCESS)));
+    return messages;
+  }
+
+  std::set<PermissionMessage> host_msgs =
+      GetHostPermissionMessages(permissions, extension_type);
+  std::set<PermissionMessage> api_msgs = GetAPIPermissionMessages(permissions);
+  messages.insert(messages.end(), host_msgs.begin(), host_msgs.end());
+  messages.insert(messages.end(), api_msgs.begin(), api_msgs.end());
+
+  return messages;
+}
+
+// static
+std::vector<string16> ChromePermissionMessageProvider::GetWarningMessages(
+    const PermissionSet* permissions,
+    Manifest::Type extension_type) const {
+  std::vector<string16> message_strings;
+  PermissionMessages messages =
+      GetPermissionMessages(permissions, extension_type);
+
+  bool audio_capture = false;
+  bool video_capture = false;
+  for (PermissionMessages::const_iterator i = messages.begin();
+       i != messages.end(); ++i) {
+    switch (i->id()) {
+      case PermissionMessage::kAudioCapture:
+        audio_capture = true;
+        break;
+      case PermissionMessage::kVideoCapture:
+        video_capture = true;
+        break;
+      default:
+        break;
+    }
+  }
+
+  for (PermissionMessages::const_iterator i = messages.begin();
+       i != messages.end(); ++i) {
+    int id = i->id();
+    if (audio_capture && video_capture) {
+      if (id == PermissionMessage::kAudioCapture) {
+        message_strings.push_back(l10n_util::GetStringUTF16(
+            IDS_EXTENSION_PROMPT_WARNING_AUDIO_AND_VIDEO_CAPTURE));
+        continue;
+      } else if (id == PermissionMessage::kVideoCapture) {
+        // The combined message will be pushed above.
+        continue;
+      }
+    }
+
+    message_strings.push_back(i->message());
+  }
+
+  return message_strings;
+}
+
+// static
+std::vector<string16>
+ChromePermissionMessageProvider::GetWarningMessagesDetails(
+    const PermissionSet* permissions,
+    Manifest::Type extension_type) const {
+  std::vector<string16> message_strings;
+  PermissionMessages messages =
+      GetPermissionMessages(permissions, extension_type);
+
+  for (PermissionMessages::const_iterator i = messages.begin();
+       i != messages.end(); ++i)
+    message_strings.push_back(i->details());
+
+  return message_strings;
+}
+
+// static
+bool ChromePermissionMessageProvider::IsPrivilegeIncrease(
+    const PermissionSet* old_permissions,
+    const PermissionSet* new_permissions,
+    Manifest::Type extension_type) const {
+  // Things can't get worse than native code access.
+  if (old_permissions->HasEffectiveFullAccess())
+    return false;
+
+  // Otherwise, it's a privilege increase if the new one has full access.
+  if (new_permissions->HasEffectiveFullAccess())
+    return true;
+
+  if (IsHostPrivilegeIncrease(old_permissions, new_permissions, extension_type))
+    return true;
+
+  if (IsAPIPrivilegeIncrease(old_permissions, new_permissions))
+    return true;
+
+  return false;
+}
+
+std::set<PermissionMessage>
+ChromePermissionMessageProvider::GetAPIPermissionMessages(
+    const PermissionSet* permissions) const {
+  std::set<PermissionMessage> messages;
+  for (APIPermissionSet::const_iterator permission_it =
+           permissions->apis().begin();
+       permission_it != permissions->apis().end(); ++permission_it) {
+    if (permission_it->HasMessages()) {
+      PermissionMessages new_messages = permission_it->GetMessages();
+      messages.insert(new_messages.begin(), new_messages.end());
+    }
+  }
+
+  // A special hack: If kFileSystemWriteDirectory would be displayed, hide
+  // kFileSystemDirectory and and kFileSystemWrite as the write directory
+  // message implies the other two.
+  // TODO(sammc): Remove this. See http://crbug.com/284849.
+  std::set<PermissionMessage>::iterator write_directory_message =
+      messages.find(PermissionMessage(
+          PermissionMessage::kFileSystemWriteDirectory, string16()));
+  if (write_directory_message != messages.end()) {
+    messages.erase(
+        PermissionMessage(PermissionMessage::kFileSystemWrite, string16()));
+    messages.erase(
+        PermissionMessage(PermissionMessage::kFileSystemDirectory, string16()));
+  }
+
+  // A special hack: The warning message for declarativeWebRequest
+  // permissions speaks about blocking parts of pages, which is a
+  // subset of what the "<all_urls>" access allows. Therefore we
+  // display only the "<all_urls>" warning message if both permissions
+  // are required.
+  if (permissions->HasEffectiveAccessToAllHosts()) {
+    messages.erase(
+        PermissionMessage(
+            PermissionMessage::kDeclarativeWebRequest, string16()));
+  }
+
+  return messages;
+}
+
+std::set<PermissionMessage>
+ChromePermissionMessageProvider::GetHostPermissionMessages(
+    const PermissionSet* permissions,
+    Manifest::Type extension_type) const {
+  std::set<PermissionMessage> messages;
+  // Since platform apps always use isolated storage, they can't (silently)
+  // access user data on other domains, so there's no need to prompt.
+  // Note: this must remain consistent with IsHostPrivilegeIncrease.
+  // See crbug.com/255229.
+  if (extension_type == Manifest::TYPE_PLATFORM_APP)
+    return messages;
+
+  if (permissions->HasEffectiveAccessToAllHosts()) {
+    messages.insert(PermissionMessage(
+        PermissionMessage::kHostsAll,
+        l10n_util::GetStringUTF16(IDS_EXTENSION_PROMPT_WARNING_ALL_HOSTS)));
+  } else {
+    URLPatternSet regular_hosts;
+    ExtensionsClient::Get()->FilterHostPermissions(
+        permissions->effective_hosts(), &regular_hosts, &messages);
+
+    std::set<std::string> hosts =
+        permission_message_util::GetDistinctHosts(regular_hosts, true, true);
+    if (!hosts.empty())
+      messages.insert(permission_message_util::CreateFromHostList(hosts));
+  }
+  return messages;
+}
+
+bool ChromePermissionMessageProvider::IsAPIPrivilegeIncrease(
+    const PermissionSet* old_permissions,
+    const PermissionSet* new_permissions) const {
+  if (new_permissions == NULL)
+    return false;
+
+  typedef std::set<PermissionMessage> PermissionMsgSet;
+  PermissionMsgSet old_warnings = GetAPIPermissionMessages(old_permissions);
+  PermissionMsgSet new_warnings = GetAPIPermissionMessages(new_permissions);
+  PermissionMsgSet delta_warnings =
+      base::STLSetDifference<PermissionMsgSet>(new_warnings, old_warnings);
+
+  // A special hack: kFileSystemWriteDirectory implies kFileSystemDirectory and
+  // kFileSystemWrite.
+  // TODO(sammc): Remove this. See http://crbug.com/284849.
+  if (old_warnings.find(PermissionMessage(
+          PermissionMessage::kFileSystemWriteDirectory, string16())) !=
+      old_warnings.end()) {
+    delta_warnings.erase(
+        PermissionMessage(PermissionMessage::kFileSystemDirectory, string16()));
+    delta_warnings.erase(
+        PermissionMessage(PermissionMessage::kFileSystemWrite, string16()));
+  }
+
+  // We have less privileges if there are additional warnings present.
+  return !delta_warnings.empty();
+}
+
+bool ChromePermissionMessageProvider::IsHostPrivilegeIncrease(
+    const PermissionSet* old_permissions,
+    const PermissionSet* new_permissions,
+    Manifest::Type extension_type) const {
+  // Platform apps host permission changes do not count as privilege increases.
+  // Note: this must remain consistent with GetHostPermissionMessages.
+  if (extension_type == Manifest::TYPE_PLATFORM_APP)
+    return false;
+
+  // If the old permission set can access any host, then it can't be elevated.
+  if (old_permissions->HasEffectiveAccessToAllHosts())
+    return false;
+
+  // Likewise, if the new permission set has full host access, then it must be
+  // a privilege increase.
+  if (new_permissions->HasEffectiveAccessToAllHosts())
+    return true;
+
+  const URLPatternSet& old_list = old_permissions->effective_hosts();
+  const URLPatternSet& new_list = new_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(
+      permission_message_util::GetDistinctHosts(new_list, false, false));
+  std::set<std::string> old_hosts_set(
+      permission_message_util::GetDistinctHosts(old_list, false, false));
+  std::set<std::string> new_hosts_only =
+      base::STLSetDifference<std::set<std::string> >(new_hosts_set,
+                                                     old_hosts_set);
+
+  return !new_hosts_only.empty();
+}
+
+}  // namespace extensions