Distinguish between user and owner passwords.

BUG=pdfium:496

Review-Url: https://codereview.chromium.org/2005653002

14 files changed, 74 insertions, 32 deletions

diff --git a/BUILD.gn b/BUILD.gn
index 1dbfea9997..2fdaa885ba 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -1659,6 +1659,7 @@ test("pdfium_embeddertests") {
   sources = [
     "core/fpdfapi/fpdf_page/fpdf_page_func_embeddertest.cpp",
     "core/fpdfapi/fpdf_parser/cpdf_parser_embeddertest.cpp",
+    "core/fpdfapi/fpdf_parser/cpdf_security_handler_embeddertest.cpp",
     "core/fpdfapi/fpdf_parser/fpdf_parser_decode_embeddertest.cpp",
     "core/fpdfapi/fpdf_render/fpdf_render_loadimage_embeddertest.cpp",
     "core/fpdfapi/fpdf_render/fpdf_render_pattern_embeddertest.cpp",
diff --git a/core/fpdfapi/fpdf_parser/cpdf_document.cpp b/core/fpdfapi/fpdf_parser/cpdf_document.cpp
index 79965a23bb..230b9b0d1b 100644
--- a/core/fpdfapi/fpdf_parser/cpdf_document.cpp
+++ b/core/fpdfapi/fpdf_parser/cpdf_document.cpp
@@ -719,9 +719,16 @@ int CPDF_Document::RetrievePageCount() const {
   return CountPages(pPages, &visited_pages);
 }
 
-uint32_t CPDF_Document::GetUserPermissions(FX_BOOL bCheckRevision) const {
-  return m_pParser ? m_pParser->GetPermissions(bCheckRevision)
-                   : static_cast<uint32_t>(-1);
+uint32_t CPDF_Document::GetUserPermissions() const {
+  // https://bugs.chromium.org/p/pdfium/issues/detail?id=499
+  if (!m_pParser) {
+#ifndef PDF_ENABLE_XFA
+    return 0;
+#else  // PDF_ENABLE_XFA
+    return 0xFFFFFFFF;
+#endif
+  }
+  return m_pParser->GetPermissions();
 }
 
 FX_BOOL CPDF_Document::IsFormStream(uint32_t objnum, FX_BOOL& bForm) const {
diff --git a/core/fpdfapi/fpdf_parser/cpdf_parser.cpp b/core/fpdfapi/fpdf_parser/cpdf_parser.cpp
index acf51de1ea..a6b99e5ddb 100644
--- a/core/fpdfapi/fpdf_parser/cpdf_parser.cpp
+++ b/core/fpdfapi/fpdf_parser/cpdf_parser.cpp
@@ -1479,16 +1479,15 @@ CPDF_Dictionary* CPDF_Parser::LoadTrailerV4() {
   return pObj.release()->AsDictionary();
 }
 
-uint32_t CPDF_Parser::GetPermissions(FX_BOOL bCheckRevision) {
+uint32_t CPDF_Parser::GetPermissions() const {
   if (!m_pSecurityHandler)
-    return (uint32_t)-1;
+    return 0xFFFFFFFF;
 
   uint32_t dwPermission = m_pSecurityHandler->GetPermissions();
   if (m_pEncryptDict && m_pEncryptDict->GetStringBy("Filter") == "Standard") {
+    // See PDF Reference 1.7, page 123, table 3.20.
     dwPermission &= 0xFFFFFFFC;
     dwPermission |= 0xFFFFF0C0;
-    if (bCheckRevision && m_pEncryptDict->GetIntegerBy("R") == 2)
-      dwPermission &= 0xFFFFF0FF;
   }
   return dwPermission;
 }
diff --git a/core/fpdfapi/fpdf_parser/cpdf_parser_embeddertest.cpp b/core/fpdfapi/fpdf_parser/cpdf_parser_embeddertest.cpp
index 042b221554..66b29a91c4 100644
--- a/core/fpdfapi/fpdf_parser/cpdf_parser_embeddertest.cpp
+++ b/core/fpdfapi/fpdf_parser/cpdf_parser_embeddertest.cpp
@@ -32,7 +32,7 @@ TEST_F(CPDFParserEmbeddertest, Bug_544880) {
 }
 
 TEST_F(CPDFParserEmbeddertest, Feature_Linearized_Loading) {
-  EXPECT_TRUE(OpenDocument("feature_linearized_loading.pdf", true));
+  EXPECT_TRUE(OpenDocument("feature_linearized_loading.pdf", nullptr, true));
 }
 
 TEST_F(CPDFParserEmbeddertest, Bug_325) {
diff --git a/core/fpdfapi/fpdf_parser/cpdf_security_handler.cpp b/core/fpdfapi/fpdf_parser/cpdf_security_handler.cpp
index d6416fb055..94ef042bc0 100644
--- a/core/fpdfapi/fpdf_parser/cpdf_security_handler.cpp
+++ b/core/fpdfapi/fpdf_parser/cpdf_security_handler.cpp
@@ -67,15 +67,15 @@ void CalcEncryptKey(CPDF_Dictionary* pEncrypt,
 
 }  // namespace
 
-CPDF_SecurityHandler::CPDF_SecurityHandler() {
-  m_Version = 0;
-  m_Revision = 0;
-  m_pParser = NULL;
-  m_pEncryptDict = NULL;
-  m_Permissions = 0;
-  m_Cipher = FXCIPHER_NONE;
-  m_KeyLen = 0;
-}
+CPDF_SecurityHandler::CPDF_SecurityHandler()
+    : m_Version(0),
+      m_Revision(0),
+      m_pParser(nullptr),
+      m_pEncryptDict(nullptr),
+      m_Permissions(0),
+      m_Cipher(FXCIPHER_NONE),
+      m_KeyLen(0),
+      m_bOwnerUnlocked(false) {}
 
 CPDF_SecurityHandler::~CPDF_SecurityHandler() {}
 
@@ -94,23 +94,21 @@ FX_BOOL CPDF_SecurityHandler::OnInit(CPDF_Parser* pParser,
   }
   return CheckSecurity(m_KeyLen);
 }
+
 FX_BOOL CPDF_SecurityHandler::CheckSecurity(int32_t key_len) {
   CFX_ByteString password = m_pParser->GetPassword();
-  if (CheckPassword(password.raw_str(), password.GetLength(), TRUE,
+  if (!password.IsEmpty() &&
+      CheckPassword(password.raw_str(), password.GetLength(), TRUE,
                     m_EncryptKey, key_len)) {
-    if (password.IsEmpty()) {
-      if (!CheckPassword(password.raw_str(), password.GetLength(), FALSE,
-                         m_EncryptKey, key_len)) {
-        return FALSE;
-      }
-    }
+    m_bOwnerUnlocked = true;
     return TRUE;
   }
   return CheckPassword(password.raw_str(), password.GetLength(), FALSE,
                        m_EncryptKey, key_len);
 }
+
 uint32_t CPDF_SecurityHandler::GetPermissions() {
-  return m_Permissions;
+  return m_bOwnerUnlocked ? 0xFFFFFFFF : m_Permissions;
 }
 
 static FX_BOOL LoadCryptInfo(CPDF_Dictionary* pEncryptDict,
diff --git a/core/fpdfapi/fpdf_parser/cpdf_security_handler.h b/core/fpdfapi/fpdf_parser/cpdf_security_handler.h
index 645c97698a..d342c1484e 100644
--- a/core/fpdfapi/fpdf_parser/cpdf_security_handler.h
+++ b/core/fpdfapi/fpdf_parser/cpdf_security_handler.h
@@ -104,6 +104,7 @@ class CPDF_SecurityHandler {
   int m_Cipher;
   uint8_t m_EncryptKey[32];
   int m_KeyLen;
+  bool m_bOwnerUnlocked;
 };
 
 #endif  // CORE_FPDFAPI_FPDF_PARSER_CPDF_SECURITY_HANDLER_H_
diff --git a/core/fpdfapi/fpdf_parser/cpdf_security_handler_embeddertest.cpp b/core/fpdfapi/fpdf_parser/cpdf_security_handler_embeddertest.cpp
new file mode 100644
index 0000000000..37b6d8fc33
--- /dev/null
+++ b/core/fpdfapi/fpdf_parser/cpdf_security_handler_embeddertest.cpp
@@ -0,0 +1,32 @@
+// Copyright 2016 PDFium 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 "testing/embedder_test.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+class CPDFSecurityHandlerEmbeddertest : public EmbedderTest {};
+
+TEST_F(CPDFSecurityHandlerEmbeddertest, Unencrypted) {
+  ASSERT_TRUE(OpenDocument("about_blank.pdf"));
+  EXPECT_EQ(0xFFFFFFFF, FPDF_GetDocPermissions(document()));
+}
+
+TEST_F(CPDFSecurityHandlerEmbeddertest, UnencryptedWithPassword) {
+  ASSERT_TRUE(OpenDocument("about_blank.pdf", "foobar"));
+  EXPECT_EQ(0xFFFFFFFF, FPDF_GetDocPermissions(document()));
+}
+
+TEST_F(CPDFSecurityHandlerEmbeddertest, NoPassword) {
+  EXPECT_FALSE(OpenDocument("encrypted.pdf"));
+}
+
+TEST_F(CPDFSecurityHandlerEmbeddertest, UserPassword) {
+  ASSERT_TRUE(OpenDocument("encrypted.pdf", "1234"));
+  EXPECT_EQ(0xFFFFF2C0, FPDF_GetDocPermissions(document()));
+}
+
+TEST_F(CPDFSecurityHandlerEmbeddertest, OwnerPassword) {
+  ASSERT_TRUE(OpenDocument("encrypted.pdf", "5678"));
+  EXPECT_EQ(0xFFFFFFFC, FPDF_GetDocPermissions(document()));
+}
diff --git a/core/fpdfapi/fpdf_parser/include/cpdf_document.h b/core/fpdfapi/fpdf_parser/include/cpdf_document.h
index 687619b763..f7a7f9f183 100644
--- a/core/fpdfapi/fpdf_parser/include/cpdf_document.h
+++ b/core/fpdfapi/fpdf_parser/include/cpdf_document.h
@@ -52,7 +52,7 @@ class CPDF_Document : public CFX_PrivateData, public CPDF_IndirectObjectHolder {
   int GetPageCount() const;
   CPDF_Dictionary* GetPage(int iPage);
   int GetPageIndex(uint32_t objnum);
-  uint32_t GetUserPermissions(FX_BOOL bCheckRevision = FALSE) const;
+  uint32_t GetUserPermissions() const;
   CPDF_DocPageData* GetPageData() const { return m_pDocPage; }
   void ClearPageData();
   void RemoveColorSpaceFromPageData(CPDF_Object* pObject);
diff --git a/core/fpdfapi/fpdf_parser/include/cpdf_parser.h b/core/fpdfapi/fpdf_parser/include/cpdf_parser.h
index 48511e9263..b468bead9d 100644
--- a/core/fpdfapi/fpdf_parser/include/cpdf_parser.h
+++ b/core/fpdfapi/fpdf_parser/include/cpdf_parser.h
@@ -38,7 +38,7 @@ class CPDF_Parser {
   ~CPDF_Parser();
 
   Error StartParse(IFX_FileRead* pFile);
-  uint32_t GetPermissions(FX_BOOL bCheckRevision = FALSE);
+  uint32_t GetPermissions() const;
 
   void SetPassword(const FX_CHAR* password) { m_Password = password; }
   CFX_ByteString GetPassword() { return m_Password; }
diff --git a/fpdfsdk/fpdfview.cpp b/fpdfsdk/fpdfview.cpp
index 020ff8df6d..e7b3a96b0b 100644
--- a/fpdfsdk/fpdfview.cpp
+++ b/fpdfsdk/fpdfview.cpp
@@ -464,15 +464,16 @@ DLLEXPORT FPDF_BOOL STDCALL FPDF_GetFileVersion(FPDF_DOCUMENT doc,
 // header).
 DLLEXPORT unsigned long STDCALL FPDF_GetDocPermissions(FPDF_DOCUMENT document) {
   CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
-  if (!pDoc || !pDoc->GetParser())
+  // https://bugs.chromium.org/p/pdfium/issues/detail?id=499
+  if (!pDoc) {
 #ifndef PDF_ENABLE_XFA
     return 0;
 #else   // PDF_ENABLE_XFA
-    return (uint32_t)-1;
+    return 0xFFFFFFFF;
 #endif  // PDF_ENABLE_XFA
+  }
 
-  CPDF_Dictionary* pDict = pDoc->GetParser()->GetEncryptDict();
-  return pDict ? pDict->GetIntegerBy("P") : (uint32_t)-1;
+  return pDoc->GetUserPermissions();
 }
 
 DLLEXPORT int STDCALL FPDF_GetSecurityHandlerRevision(FPDF_DOCUMENT document) {
diff --git a/pdfium.gyp b/pdfium.gyp
index 69f6908ccf..3a3bf69f42 100644
--- a/pdfium.gyp
+++ b/pdfium.gyp
@@ -974,6 +974,7 @@
       'sources': [
         'core/fpdfapi/fpdf_page/fpdf_page_func_embeddertest.cpp',
         'core/fpdfapi/fpdf_parser/cpdf_parser_embeddertest.cpp',
+        'core/fpdfapi/fpdf_parser/cpdf_security_handler_embeddertest.cpp',
         'core/fpdfapi/fpdf_parser/fpdf_parser_decode_embeddertest.cpp',
         'core/fpdfapi/fpdf_render/fpdf_render_loadimage_embeddertest.cpp',
         'core/fpdfapi/fpdf_render/fpdf_render_pattern_embeddertest.cpp',
diff --git a/testing/embedder_test.cpp b/testing/embedder_test.cpp
index 38a3dcdeca..033313dbe2 100644
--- a/testing/embedder_test.cpp
+++ b/testing/embedder_test.cpp
@@ -111,6 +111,7 @@ bool EmbedderTest::CreateEmptyDocument() {
 }
 
 bool EmbedderTest::OpenDocument(const std::string& filename,
+                                const char* password,
                                 bool must_linearize) {
   std::string file_path;
   if (!PathService::GetTestFilePath(filename, &file_path))
@@ -133,7 +134,7 @@ bool EmbedderTest::OpenDocument(const std::string& filename,
   avail_ = FPDFAvail_Create(&file_avail_, &file_access_);
 
   if (FPDFAvail_IsLinearized(avail_) == PDF_LINEARIZED) {
-    document_ = FPDFAvail_GetDocument(avail_, nullptr);
+    document_ = FPDFAvail_GetDocument(avail_, password);
     if (!document_) {
       return false;
     }
diff --git a/testing/embedder_test.h b/testing/embedder_test.h
index a21a55de2c..a176d944c0 100644
--- a/testing/embedder_test.h
+++ b/testing/embedder_test.h
@@ -88,6 +88,7 @@ class EmbedderTest : public ::testing::Test,
   // The filename is relative to the test data directory where we store all the
   // test files.
   virtual bool OpenDocument(const std::string& filename,
+                            const char* password = nullptr,
                             bool must_linearize = false);
 
   // Perform JavaScript actions that are to run at document open time.
diff --git a/testing/resources/encrypted.pdf b/testing/resources/encrypted.pdf
new file mode 100644
index 0000000000..b489d56ff2
--- /dev/null
+++ b/testing/resources/encrypted.pdf