[unseasoned-pdf] Provide common interface for content restrictions

Introduce a new enum, chrome_pdf::ContentRestriction, which maps to
PP_ContentRestriction and transitively to ContentRestriction, as a
Pepper-free enum for content restrictions that can be used in //pdf/.

Provide a common interface for setting content restrictions. The
OutOfProcessInstance implementation will call
pp::PDF::SetContentRestriction, while the PdfViewWebPlugin will stay
empty for now.

Bug: 1140629
Change-Id: I0d49860f19066d7e9ae8a5999a43395e5b751ffe
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2785924
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Daniel Hosseinian <dhoss@chromium.org>
Cr-Commit-Position: refs/heads/master@{#866764}

pdf/BUILD.gn

@@ -80,6 +80,7 @@ if (enable_pdf) {
       "accessibility.cc",
       "accessibility.h",
       "chunk_stream.h",
+      "content_restriction.h",
       "document_attachment_info.cc",
       "document_attachment_info.h",
       "document_layout.cc",

pdf/content_restriction.h

@@ -0,0 +1,26 @@
+// Copyright 2021 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.
+
+#ifndef PDF_CONTENT_RESTRICTION_H_
+#define PDF_CONTENT_RESTRICTION_H_
+
+namespace chrome_pdf {
+
+// Used for disabling browser commands because of restrictions on how the data
+// is to be used (i.e. can't copy/print).
+// TODO(crbug.com/702993): Must be kept in sync with `ContentRestriction` in
+// chrome/common/content_restriction.h. While there's a transitive static
+// assertion that the enums match, a direct static assertion should be added
+// when `PP_ContentRestriction` is removed.
+enum ContentRestriction {
+  kContentRestrictionCopy = 1 << 0,
+  kContentRestrictionCut = 1 << 1,
+  kContentRestrictionPaste = 1 << 2,
+  kContentRestrictionPrint = 1 << 3,
+  kContentRestrictionSave = 1 << 4
+};
+
+}  // namespace chrome_pdf
+
+#endif  // PDF_CONTENT_RESTRICTION_H_

pdf/out_of_process_instance.cc

@@ -29,6 +29,7 @@
 #include "net/base/escape.h"
 #include "pdf/accessibility.h"
 #include "pdf/accessibility_structs.h"
+#include "pdf/content_restriction.h"
 #include "pdf/document_attachment_info.h"
 #include "pdf/document_metadata.h"
 #include "pdf/pdfium/pdfium_engine.h"
@@ -1007,8 +1008,7 @@ std::unique_ptr<UrlLoader> OutOfProcessInstance::CreateUrlLoader() {
     // Disable save and print until the document is fully loaded, since they
     // would generate an incomplete document.  Need to do this each time we
     // call DidStartLoading since that resets the content restrictions.
-    pp::PDF::SetContentRestriction(
-        this, PP_CONTENT_RESTRICTION_SAVE | PP_CONTENT_RESTRICTION_PRINT);
+    SetContentRestrictions(kContentRestrictionSave | kContentRestrictionPrint);
   }
 
   return CreateUrlLoaderInternal();
@@ -1074,17 +1074,16 @@ void OutOfProcessInstance::DocumentLoadComplete() {
     did_call_start_loading_ = false;
   }
 
-  int content_restrictions =
-      PP_CONTENT_RESTRICTION_CUT | PP_CONTENT_RESTRICTION_PASTE;
+  int content_restrictions = kContentRestrictionCut | kContentRestrictionPaste;
   if (!engine()->HasPermission(PDFEngine::PERMISSION_COPY))
-    content_restrictions |= PP_CONTENT_RESTRICTION_COPY;
+    content_restrictions |= kContentRestrictionCopy;
 
   if (!engine()->HasPermission(PDFEngine::PERMISSION_PRINT_LOW_QUALITY) &&
       !engine()->HasPermission(PDFEngine::PERMISSION_PRINT_HIGH_QUALITY)) {
-    content_restrictions |= PP_CONTENT_RESTRICTION_PRINT;
+    content_restrictions |= kContentRestrictionPrint;
   }
 
-  pp::PDF::SetContentRestriction(this, content_restrictions);
+  SetContentRestrictions(content_restrictions);
 }
 
 void OutOfProcessInstance::RotateClockwise() {
@@ -1461,6 +1460,10 @@ void OutOfProcessInstance::LoadNextPreviewPage() {
   }
 }
 
+void OutOfProcessInstance::SetContentRestrictions(int content_restrictions) {
+  pp::PDF::SetContentRestriction(this, content_restrictions);
+}
+
 void OutOfProcessInstance::UserMetricsRecordAction(const std::string& action) {
   // TODO(raymes): Move this function to PPB_UMA_Private.
   pp::PDF::UserMetricsRecordAction(this, pp::Var(action));

pdf/out_of_process_instance.h

@@ -156,6 +156,7 @@ class OutOfProcessInstance : public PdfViewPluginBase,
                                 AccessibilityPageObjects page_objects) override;
   void SetAccessibilityViewportInfo(
       const AccessibilityViewportInfo& viewport_info) override;
+  void SetContentRestrictions(int content_restrictions) override;
   void UserMetricsRecordAction(const std::string& action) override;
 
  private:

pdf/pdf_view_plugin_base.h

@@ -247,6 +247,11 @@ class PdfViewPluginBase : public PDFEngine::Client,
     return size > 0 && size <= kMaximumSavedFileSize;
   }
 
+  // Disables browser commands because of restrictions on how the data is to be
+  // used (i.e. can't copy/print). `content_restrictions` should have its bits
+  // set by `chrome_pdf::ContentRestriction` enum values.
+  virtual void SetContentRestrictions(int content_restrictions) = 0;
+
   // Records metrics about the document metadata.
   void RecordDocumentMetrics();
 

pdf/pdf_view_plugin_base_unittest.cc

@@ -113,6 +113,8 @@ class FakePdfViewPluginBase : public PdfViewPluginBase {
               (const AccessibilityViewportInfo&),
               (override));
 
+  MOCK_METHOD(void, SetContentRestrictions, (int), (override));
+
   MOCK_METHOD(void, UserMetricsRecordAction, (const std::string&), (override));
 
   base::Value sent_message_;

pdf/pdf_view_web_plugin.cc

@@ -442,6 +442,10 @@ void PdfViewWebPlugin::SetAccessibilityViewportInfo(
   NOTIMPLEMENTED();
 }
 
+void PdfViewWebPlugin::SetContentRestrictions(int content_restrictions) {
+  NOTIMPLEMENTED();
+}
+
 void PdfViewWebPlugin::UserMetricsRecordAction(const std::string& action) {
   base::RecordAction(base::UserMetricsAction(action.c_str()));
 }

pdf/pdf_view_web_plugin.h

@@ -129,6 +129,7 @@ class PdfViewWebPlugin final : public PdfViewPluginBase,
                                 AccessibilityPageObjects page_objects) override;
   void SetAccessibilityViewportInfo(
       const AccessibilityViewportInfo& viewport_info) override;
+  void SetContentRestrictions(int content_restrictions) override;
   void UserMetricsRecordAction(const std::string& action) override;
 
  private:

pdf/pdfium/pdfium_assert_matching_enums.cc

@@ -4,6 +4,7 @@
 
 #include "build/build_config.h"
 #include "pdf/accessibility_structs.h"
+#include "pdf/content_restriction.h"
 #include "pdf/document_metadata.h"
 #include "pdf/ppapi_migration/input_event_conversions.h"
 #include "ppapi/c/pp_input_event.h"
@@ -394,3 +395,14 @@ STATIC_ASSERT_ENUM(chrome_pdf::AccessibilityScrollAlignment::kClosestToEdge,
                    PP_PDF_SCROLL_ALIGNMENT_CLOSEST_EDGE);
 STATIC_ASSERT_ENUM(chrome_pdf::AccessibilityScrollAlignment::kMaxValue,
                    PP_PDF_ACCESSIBILITYSCROLLALIGNMENT_LAST);
+
+STATIC_ASSERT_ENUM(chrome_pdf::kContentRestrictionCopy,
+                   PP_CONTENT_RESTRICTION_COPY);
+STATIC_ASSERT_ENUM(chrome_pdf::kContentRestrictionCut,
+                   PP_CONTENT_RESTRICTION_CUT);
+STATIC_ASSERT_ENUM(chrome_pdf::kContentRestrictionPaste,
+                   PP_CONTENT_RESTRICTION_PASTE);
+STATIC_ASSERT_ENUM(chrome_pdf::kContentRestrictionPrint,
+                   PP_CONTENT_RESTRICTION_PRINT);
+STATIC_ASSERT_ENUM(chrome_pdf::kContentRestrictionSave,
+                   PP_CONTENT_RESTRICTION_SAVE);