[xfa] Remove form checksum abilities

This CL removes the code for verifying and creating checksums associated
with form elements in XFA documents. This was the only code requiring
the SAXReader which has also been removed.

According to the XFA spec and application can decide which parts of the
signatures are supported. This feature is being removed until we
determine if/when it is needed.

Bug: pdfium:1063
Change-Id: Iec2261282340f8fc72a1225d2e0d3e6ddf05edcb
Reviewed-on: https://pdfium-review.googlesource.com/30150
Reviewed-by: Ryan Harrison <rharrison@chromium.org>
Commit-Queue: dsinclair <dsinclair@chromium.org>

2 files changed, 10 insertions, 30 deletions

diff --git a/fpdfsdk/fpdf_save.cpp b/fpdfsdk/fpdf_save.cpp
index da3e12fc9c..cd1889e005 100644
--- a/fpdfsdk/fpdf_save.cpp
+++ b/fpdfsdk/fpdf_save.cpp
@@ -23,7 +23,6 @@
 #include "public/fpdf_edit.h"
 
 #ifdef PDF_ENABLE_XFA
-#include "core/fxcrt/cfx_checksumcontext.h"
 #include "fpdfsdk/fpdfxfa/cpdfxfa_context.h"
 #include "fpdfsdk/fpdfxfa/cxfa_fwladaptertimermgr.h"
 #include "public/fpdf_formfill.h"
@@ -79,7 +78,6 @@ bool SaveXFADocumentData(CPDFXFA_Context* pContext,
   int size = pArray->GetCount();
   int iFormIndex = -1;
   int iDataSetsIndex = -1;
-  int iTemplate = -1;
   int iLast = size - 2;
   for (int i = 0; i < size - 1; i++) {
     CPDF_Object* pPDFObj = pArray->GetObjectAt(i);
@@ -89,22 +87,8 @@ bool SaveXFADocumentData(CPDFXFA_Context* pContext,
       iFormIndex = i + 1;
     else if (pPDFObj->GetString() == "datasets")
       iDataSetsIndex = i + 1;
-    else if (pPDFObj->GetString() == "template")
-      iTemplate = i + 1;
-  }
-  auto pChecksum = pdfium::MakeUnique<CFX_ChecksumContext>();
-  pChecksum->StartChecksum();
-
-  // template
-  if (iTemplate > -1) {
-    CPDF_Stream* pTemplateStream = pArray->GetStreamAt(iTemplate);
-    auto pAcc = pdfium::MakeRetain<CPDF_StreamAcc>(pTemplateStream);
-    pAcc->LoadAllDataFiltered();
-    RetainPtr<IFX_SeekableStream> pTemplate =
-        pdfium::MakeRetain<CFX_MemoryStream>(
-            const_cast<uint8_t*>(pAcc->GetData()), pAcc->GetSize(), false);
-    pChecksum->UpdateChecksum(pTemplate);
   }
+
   CPDF_Stream* pFormStream = nullptr;
   CPDF_Stream* pDataSetsStream = nullptr;
   if (iFormIndex != -1) {
@@ -140,11 +124,8 @@ bool SaveXFADocumentData(CPDFXFA_Context* pContext,
     CXFA_FFDoc* ffdoc = pXFADocView->GetDoc();
     if (ffdoc->SavePackage(
             ToNode(ffdoc->GetXFADoc()->GetXFAObject(XFA_HASHCODE_Datasets)),
-            pDsfileWrite, nullptr) &&
+            pDsfileWrite) &&
         pDsfileWrite->GetSize() > 0) {
-      // Datasets
-      pChecksum->UpdateChecksum(pDsfileWrite);
-      pChecksum->FinishChecksum();
       auto pDataDict = pdfium::MakeUnique<CPDF_Dictionary>(
           pPDFDocument->GetByteStringPool());
       if (iDataSetsIndex != -1) {
@@ -171,7 +152,7 @@ bool SaveXFADocumentData(CPDFXFA_Context* pContext,
     CXFA_FFDoc* ffdoc = pXFADocView->GetDoc();
     if (ffdoc->SavePackage(
             ToNode(ffdoc->GetXFADoc()->GetXFAObject(XFA_HASHCODE_Form)),
-            pfileWrite, pChecksum.get()) &&
+            pfileWrite) &&
         pfileWrite->GetSize() > 0) {
       auto pDataDict = pdfium::MakeUnique<CPDF_Dictionary>(
           pPDFDocument->GetByteStringPool());
diff --git a/fpdfsdk/fpdfxfa/cpdfxfa_docenvironment.cpp b/fpdfsdk/fpdfxfa/cpdfxfa_docenvironment.cpp
index 1b503b3fca..4bf6064a34 100644
--- a/fpdfsdk/fpdfxfa/cpdfxfa_docenvironment.cpp
+++ b/fpdfsdk/fpdfxfa/cpdfxfa_docenvironment.cpp
@@ -453,8 +453,7 @@ void CPDFXFA_DocEnvironment::ExportData(CXFA_FFDoc* hDoc,
                           content.GetLength());
     CXFA_FFDoc* ffdoc = m_pContext->GetXFADocView()->GetDoc();
     ffdoc->SavePackage(
-        ToNode(ffdoc->GetXFADoc()->GetXFAObject(XFA_HASHCODE_Data)), fileWrite,
-        nullptr);
+        ToNode(ffdoc->GetXFADoc()->GetXFAObject(XFA_HASHCODE_Data)), fileWrite);
   } else if (fileType == FXFA_SAVEAS_XDP) {
     if (!m_pContext->GetPDFDoc())
       return;
@@ -487,14 +486,14 @@ void CPDFXFA_DocEnvironment::ExportData(CXFA_FFDoc* hDoc,
         CXFA_FFDoc* ffdoc = m_pContext->GetXFADocView()->GetDoc();
         ffdoc->SavePackage(
             ToNode(ffdoc->GetXFADoc()->GetXFAObject(XFA_HASHCODE_Form)),
-            fileWrite, nullptr);
+            fileWrite);
         continue;
       }
       if (pPrePDFObj->GetString() == "datasets") {
         CXFA_FFDoc* ffdoc = m_pContext->GetXFADocView()->GetDoc();
         ffdoc->SavePackage(
             ToNode(ffdoc->GetXFADoc()->GetXFAObject(XFA_HASHCODE_Datasets)),
-            fileWrite, nullptr);
+            fileWrite);
         continue;
       }
       if (i == size - 1) {
@@ -740,8 +739,8 @@ bool CPDFXFA_DocEnvironment::ExportSubmitFile(FPDF_FILEHANDLER* pFileHandler,
     fileStream->WriteBlock(kContent, 0, strlen(kContent));
 
     ffdoc->SavePackage(
-        ToNode(ffdoc->GetXFADoc()->GetXFAObject(XFA_HASHCODE_Data)), fileStream,
-        nullptr);
+        ToNode(ffdoc->GetXFADoc()->GetXFAObject(XFA_HASHCODE_Data)),
+        fileStream);
     return true;
   }
 
@@ -805,11 +804,11 @@ bool CPDFXFA_DocEnvironment::ExportSubmitFile(FPDF_FILEHANDLER* pFileHandler,
     if (pPrePDFObj->GetString() == "form") {
       ffdoc->SavePackage(
           ToNode(ffdoc->GetXFADoc()->GetXFAObject(XFA_HASHCODE_Form)),
-          fileStream, nullptr);
+          fileStream);
     } else if (pPrePDFObj->GetString() == "datasets") {
       ffdoc->SavePackage(
           ToNode(ffdoc->GetXFADoc()->GetXFAObject(XFA_HASHCODE_Datasets)),
-          fileStream, nullptr);
+          fileStream);
     }
   }
   return true;