Add ability to clear content licenses

content/browser/storage_partition_impl.cc

Index: content/browser/storage_partition_impl.cc
diff --git a/content/browser/storage_partition_impl.cc b/content/browser/storage_partition_impl.cc
index 65bf56140be1ff27696d83e7f5f483486b15345b..e26a224c3803a0bd8948e4fb700d826daccfe39a 100644
--- a/content/browser/storage_partition_impl.cc
+++ b/content/browser/storage_partition_impl.cc
@@ -34,12 +34,19 @@
 #include "net/url_request/url_request_context.h"
 #include "net/url_request/url_request_context_getter.h"
 #include "storage/browser/database/database_tracker.h"
+#include "storage/browser/fileapi/async_file_util.h"
+#include "storage/browser/fileapi/isolated_context.h"
 #include "storage/browser/quota/quota_manager.h"
+#include "storage/common/fileapi/file_system_util.h"
 
 namespace content {
 
 namespace {
 
+const char kPluginPrivateRootName[] = "pluginprivate";

[xhwang, 2016/05/16 17:35:23]

Is this documented anywhere? Where is this magic string coming from?

[jrummell, 2016/05/19 00:45:57]

It comes from the pepper code, that converts the pepper filesystem type to a
root name. Added a shared definition for it.

+const char kWidevineCdmPluginId[] = "application_x-ppapi-widevine-cdm";
+const char kClearKeyCdmPluginId[] = "application_x-ppapi-clearkey-cdm";

[xhwang, 2016/05/16 17:35:23]

In other places the pepper type is application/x-ppapi-clearkey-cdm

Is there a special rule about how plugin IDs are generated?

[jrummell, 2016/05/19 00:45:56]

The conversion is done in GeneratePluginId [1] which takes a mime-type and
basically puts an _ between the top_level_type and the subtype. It's in pepper
code, and we don't need the other validation it does ("contains only alphabets,
digits, or "._-".").

[1]
https://code.google.com/p/chromium/codesearch#chromium/src/content/browser/re...

+
 bool DoesCookieMatchHost(const std::string& host,
                          const net::CanonicalCookie& cookie) {
   return cookie.IsHostCookie() && cookie.IsDomainMatch(host);
@@ -215,6 +222,325 @@ void ClearSessionStorageOnUIThread(
                  callback));
 }
 
+// Helper for deleting content licenses for a specified origin and plugin.
+// If any file matches the time range specified, then all files for this
+// origin and plugin are deleted.
+// All of the operations in this class are done on the FILE thread.
+class PluginPrivateContentLicensesDeletionHelper {

[xhwang, 2016/05/16 17:35:23]

About naming: The UI is TBD and is subject to change. So I am not sure about the
"ContentLicenses" part. Shall we stick with what we have in the implementation
(i.e. PluginPrivate), and try to avoid "content licenses" in this backend code?

[jrummell, 2016/05/19 00:45:56]

Done.

+ public:
+  PluginPrivateContentLicensesDeletionHelper(
+      const scoped_refptr<storage::FileSystemContext>& filesystem_context,
+      const GURL& origin,
+      const std::string& plugin_name,
+      const base::Time begin,
+      const base::Time end,
+      const base::Closure& callback)
+      : filesystem_context_(std::move(filesystem_context)),
+        origin_(origin),
+        plugin_name_(plugin_name),
+        begin_(begin),
+        end_(end),
+        callback_(callback) {
+    // Create the filesystem ID.
+    fsid_ = storage::IsolatedContext::GetInstance()
+                ->RegisterFileSystemForVirtualPath(
+                    storage::kFileSystemTypePluginPrivate,
+                    kPluginPrivateRootName, base::FilePath());
+  }
+  ~PluginPrivateContentLicensesDeletionHelper() {}
+
+  // Checks the files contained in the plugin private filesystem for |origin_|
+  // and |plugin_name_| and deletes any files whose last modified time is
+  // greater or equal to |begin_|. |callback_| is called when all actions
+  // are complete.
+  void Start();
+
+ private:
+  void OnFileSystemOpened(base::File::Error result);
+  void OnDirectoryRead(const std::string& root,
+                       base::File::Error result,
+                       const storage::AsyncFileUtil::EntryList& file_list,
+                       bool has_more);
+  void OnFileInfo(const std::string& file_name,
+                  const storage::FileSystemURL& file_url,
+                  base::File::Error result,
+                  const base::File::Info& file_info);
+
+  // Keeps track of the pending work. When |task_count_| goes to 0 then
+  // |callback_| is called and this helper object is destroyed.
+  void IncrementTaskCount();
+  void DecrementTaskCount();
+
+  scoped_refptr<storage::FileSystemContext> filesystem_context_;
+  GURL origin_;
+  std::string plugin_name_;
+  base::Time begin_;
+  base::Time end_;
+  base::Closure callback_;
+  std::string fsid_;
+  int task_count_ = 0;
+  bool delete_this_data_ = false;
+};
+
+void PluginPrivateContentLicensesDeletionHelper::Start() {
+  DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+  DCHECK(storage::ValidateIsolatedFileSystemId(fsid_));
+
+  IncrementTaskCount();
+  filesystem_context_->OpenPluginPrivateFileSystem(
+      origin_, storage::kFileSystemTypePluginPrivate, fsid_, plugin_name_,
+      storage::OPEN_FILE_SYSTEM_FAIL_IF_NONEXISTENT,
+      base::Bind(
+          &PluginPrivateContentLicensesDeletionHelper::OnFileSystemOpened,
+          base::Unretained(this)));
+}
+
+void PluginPrivateContentLicensesDeletionHelper::OnFileSystemOpened(
+    base::File::Error result) {
+  DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+  DVLOG(3) << "Opened filesystem for " << origin_ << ":" << plugin_name_
+           << ", result: " << result;
+
+  // If we can't open the directory, we can't delete files so simply return.
+  if (result != base::File::FILE_OK) {
+    DecrementTaskCount();
+    return;
+  }
+
+  storage::AsyncFileUtil* file_util = filesystem_context_->GetAsyncFileUtil(
+      storage::kFileSystemTypePluginPrivate);
+  std::string root = storage::GetIsolatedFileSystemRootURIString(
+      origin_, fsid_, kPluginPrivateRootName);
+  std::unique_ptr<storage::FileSystemOperationContext> operation_context =
+      base::WrapUnique(
+          new storage::FileSystemOperationContext(filesystem_context_.get()));
+  file_util->ReadDirectory(
+      std::move(operation_context), filesystem_context_->CrackURL(GURL(root)),
+      base::Bind(&PluginPrivateContentLicensesDeletionHelper::OnDirectoryRead,
+                 base::Unretained(this), root));
+}
+
+void PluginPrivateContentLicensesDeletionHelper::OnDirectoryRead(
+    const std::string& root,
+    base::File::Error result,
+    const storage::AsyncFileUtil::EntryList& file_list,
+    bool has_more) {
+  DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+  DVLOG(3) << __FUNCTION__ << " result: " << result
+           << ", #files: " << file_list.size();
+
+  // Quit if there is an error.
+  if (result != base::File::FILE_OK) {
+    DLOG(ERROR) << "Unable to read directory for " << origin_ << ":"
+                << plugin_name_;
+    DecrementTaskCount();
+    return;
+  }
+
+  // No error, process the files returned.
+  storage::AsyncFileUtil* file_util = filesystem_context_->GetAsyncFileUtil(
+      storage::kFileSystemTypePluginPrivate);
+  for (const auto& file : file_list) {
+    DVLOG(3) << __FUNCTION__ << " file: " << file.name;
+    DCHECK(!file.is_directory);  // Nested directories not implemented.
+
+    std::unique_ptr<storage::FileSystemOperationContext> operation_context =
+        base::WrapUnique(
+            new storage::FileSystemOperationContext(filesystem_context_.get()));
+    storage::FileSystemURL file_url =
+        filesystem_context_->CrackURL(GURL(root + file.name));
+    IncrementTaskCount();
+    file_util->GetFileInfo(
+        std::move(operation_context), file_url,
+        storage::FileSystemOperation::GET_METADATA_FIELD_SIZE |
+            storage::FileSystemOperation::GET_METADATA_FIELD_LAST_MODIFIED,
+        base::Bind(&PluginPrivateContentLicensesDeletionHelper::OnFileInfo,
+                   base::Unretained(this), file.name, file_url));
+  }
+
+  // If there are more files in this directory, wait for the next call.
+  if (has_more)
+    return;
+
+  DecrementTaskCount();
+}
+
+void PluginPrivateContentLicensesDeletionHelper::OnFileInfo(
+    const std::string& file_name,
+    const storage::FileSystemURL& file_url,
+    base::File::Error result,
+    const base::File::Info& file_info) {
+  DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+
+  if (result == base::File::FILE_OK) {
+    DVLOG(3) << __FUNCTION__ << " name: " << file_name
+             << ", size: " << file_info.size
+             << ", modified: " << file_info.last_modified;
+    if (file_info.last_modified >= begin_ && file_info.last_modified <= end_)
+      delete_this_data_ = true;
+  }
+
+  DecrementTaskCount();
+}
+
+void PluginPrivateContentLicensesDeletionHelper::IncrementTaskCount() {
+  DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+  ++task_count_;
+}
+
+void PluginPrivateContentLicensesDeletionHelper::DecrementTaskCount() {
+  DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+  DCHECK_GT(task_count_, 0);
+  --task_count_;
+  if (task_count_)
+    return;
+
+  // If there are no more tasks in progress, then delete the files for this
+  // origin if necessary.
+  if (delete_this_data_) {
+    DVLOG(3) << "Deleting content licenses for " << origin_ << ":"
+             << plugin_name_;
+    storage::FileSystemBackend* backend =
+        filesystem_context_->GetFileSystemBackend(
+            storage::kFileSystemTypePluginPrivate);
+    storage::FileSystemQuotaUtil* quota_util = backend->GetQuotaUtil();
+    base::File::Error result = quota_util->DeleteOriginDataOnFileTaskRunner(
+        filesystem_context_.get(), nullptr, origin_,
+        storage::kFileSystemTypePluginPrivate);
+    DLOG_IF(ERROR, result != base::File::FILE_OK)
+        << "Unable to delete the content licenses for " << origin_ << ":"
+        << plugin_name_;
+  }
+
+  // Run |callback_| and then this helper can be deleted.
+  callback_.Run();
+  delete this;
+}
+
+// Helper for deleting content licenses.
+// All of the operations in this class are done on the FILE thread.
+class ContentLicensesDeletionHelper {
+ public:
+  ContentLicensesDeletionHelper(
+      const scoped_refptr<storage::FileSystemContext>& filesystem_context,
+      const base::Time begin,
+      const base::Time end,
+      const base::Closure& callback)
+      : filesystem_context_(std::move(filesystem_context)),
+        begin_(begin),
+        end_(end),
+        callback_(callback) {}
+  ~ContentLicensesDeletionHelper() {}
+
+  void CheckOrigins(const std::set<GURL>& origins);
+
+ private:
+  // Keeps track of the pending work. When |task_count_| goes to 0 then
+  // |callback_| is called and this helper object is destroyed.
+  void IncrementTaskCount();
+  void DecrementTaskCount();
+
+  scoped_refptr<storage::FileSystemContext> filesystem_context_;
+  base::Time begin_;
+  base::Time end_;
+  base::Closure callback_;
+  int task_count_ = 0;
+};
+
+void ContentLicensesDeletionHelper::CheckOrigins(
+    const std::set<GURL>& origins) {
+  DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+  IncrementTaskCount();
+
+  std::vector<std::string> supported_plugins = {
+      kWidevineCdmPluginId, kClearKeyCdmPluginId,
+  };
+  // TODO(jrummell): Is there any way to determine the set of plugin IDs
+  // directly from the filesystem?

[xhwang, 2016/05/16 17:35:23]

We should ask storage owners about this.

[jrummell, 2016/05/19 00:45:57]

Done.

+  base::Closure decrement_callback =
+      base::Bind(&ContentLicensesDeletionHelper::DecrementTaskCount,
+                 base::Unretained(this));
+  for (const auto& origin : origins) {
+    for (const auto& plugin : supported_plugins) {
+      IncrementTaskCount();
+      PluginPrivateContentLicensesDeletionHelper* helper =
+          new PluginPrivateContentLicensesDeletionHelper(
+              filesystem_context_, origin.GetOrigin(), plugin, begin_, end_,
+              decrement_callback);
+      helper->Start();
+    }
+  }
+
+  // Cancels out the call to IncrementTaskCount() at the start of this method.
+  // If there are no origins specified then this will cause this helper to
+  // be destroyed.
+  DecrementTaskCount();
+}
+
+void ContentLicensesDeletionHelper::IncrementTaskCount() {
+  DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+  ++task_count_;
+}
+
+void ContentLicensesDeletionHelper::DecrementTaskCount() {
+  DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+  DCHECK_GT(task_count_, 0);
+  --task_count_;
+  if (task_count_)
+    return;
+
+  // If there are no more tasks in progress, run |callback_| and then
+  // this helper can be deleted.
+  callback_.Run();
+  delete this;
+}
+
+void ClearContentLicensesOnFileThread(

[xhwang, 2016/05/16 17:35:23]

Can we document about thread safety? For example, this runs on the same thread
as other file operations (open/read/write). Also, what happens if we call this
after a file is opened, but before read, or before a write? Some kind of failure
is okay, but we need to guarantee the integrity of data.

+    const scoped_refptr<storage::FileSystemContext>& filesystem_context,
+    const GURL& storage_origin,
+    const base::Time begin,
+    const base::Time end,
+    const base::Closure& callback) {
+  DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+  DVLOG(3) << "Clearing content licenses for origin: " << storage_origin;
+
+  storage::FileSystemBackend* backend =
+      filesystem_context->GetFileSystemBackend(
+          storage::kFileSystemTypePluginPrivate);
+  storage::FileSystemQuotaUtil* quota_util = backend->GetQuotaUtil();
+
+  // Determine the set of origins used.
+  std::set<GURL> origins;
+  quota_util->GetOriginsForTypeOnFileTaskRunner(
+      storage::kFileSystemTypePluginPrivate, &origins);
+
+  if (origins.empty()) {
+    // No origins, so nothing to do.
+    callback.Run();
+    return;
+  }
+
+  // If a specific origin is provided, then check that it is in the list
+  // returned and remove all the other origins.
+  if (!storage_origin.is_empty()) {
+    auto it = origins.find(storage_origin);
+    if (it == origins.end()) {
+      // Nothing matches, so nothing to do.
+      callback.Run();
+      return;
+    }
+
+    // List should only contain the one value that matches.
+    origins.clear();
+    origins.insert(storage_origin);
+  }
+
+  ContentLicensesDeletionHelper* helper = new ContentLicensesDeletionHelper(
+      std::move(filesystem_context), begin, end, callback);
+  helper->CheckOrigins(origins);
+  // |helper| will delete itself when all origins have been checked.
+}
+
 }  // namespace
 
 // Static.
@@ -316,6 +642,7 @@ struct StoragePartitionImpl::DataDeletionHelper {
       storage::QuotaManager* quota_manager,
       storage::SpecialStoragePolicy* special_storage_policy,
       WebRTCIdentityStore* webrtc_identity_store,
+      storage::FileSystemContext* filesystem_context,
       const base::Time begin,
       const base::Time end);
 
@@ -635,7 +962,8 @@ void StoragePartitionImpl::ClearDataImpl(
   helper->ClearDataOnUIThread(
       storage_origin, origin_matcher, cookie_matcher, GetPath(), rq_context,
       dom_storage_context_.get(), quota_manager_.get(),
-      special_storage_policy_.get(), webrtc_identity_store_.get(), begin, end);
+      special_storage_policy_.get(), webrtc_identity_store_.get(),
+      filesystem_context_.get(), begin, end);
 }
 
 void StoragePartitionImpl::
@@ -775,6 +1103,7 @@ void StoragePartitionImpl::DataDeletionHelper::ClearDataOnUIThread(
     storage::QuotaManager* quota_manager,
     storage::SpecialStoragePolicy* special_storage_policy,
     WebRTCIdentityStore* webrtc_identity_store,
+    storage::FileSystemContext* filesystem_context,
     const base::Time begin,
     const base::Time end) {
   DCHECK_NE(remove_mask, 0u);
@@ -855,6 +1184,15 @@ void StoragePartitionImpl::DataDeletionHelper::ClearDataOnUIThread(
                    decrement_callback));
   }
 
+  if (remove_mask & REMOVE_DATA_MASK_CONTENT_LICENSES) {
+    IncrementTaskCountOnUI();
+    BrowserThread::PostTask(
+        BrowserThread::FILE, FROM_HERE,
+        base::Bind(&ClearContentLicensesOnFileThread,
+                   make_scoped_refptr(filesystem_context), storage_origin,
+                   begin, end, decrement_callback));
+  }
+
   DecrementTaskCountOnUI();
 }