diff options
| author | Miklos Vajna <vmiklos@collabora.com> | 2020-09-04 17:17:48 +0200 |
|---|---|---|
| committer | Miklos Vajna <vmiklos@collabora.com> | 2020-09-04 18:39:37 +0200 |
| commit | 61834cd574568613f0b0a2ee099a60fa5a8d9804 (patch) | |
| tree | a53cbd1242fcf6450512148473743bf551c57061 /vcl/source | |
| parent | c9173b4042d6d4dc2e4b028e133ea60631f6e87d (diff) | |
xmlsecurity: pdf incremental updates that are non-commenting are invalid
I.e. it's OK to add incremental updates for annotation/commenting
purposes and that doesn't invalite existing signatures. Everything else
does.
Change-Id: I4607c242b3c6f6b01517b02407e9e7a095e2e069
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/102057
Reviewed-by: Miklos Vajna <vmiklos@collabora.com>
Tested-by: Jenkins
Diffstat (limited to 'vcl/source')
| -rw-r--r-- | vcl/source/pdf/PDFiumLibrary.cxx | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/vcl/source/pdf/PDFiumLibrary.cxx b/vcl/source/pdf/PDFiumLibrary.cxx index d77a2f8da663..bacb45097c1b 100644 --- a/vcl/source/pdf/PDFiumLibrary.cxx +++ b/vcl/source/pdf/PDFiumLibrary.cxx @@ -17,6 +17,10 @@ #include <fpdf_edit.h> #include <fpdf_text.h> +#include <vcl/bitmap.hxx> + +#include <bitmapwriteaccess.hxx> + namespace vcl::pdf { OUString convertPdfDateToISO8601(OUString const& rInput) @@ -328,6 +332,34 @@ std::unique_ptr<PDFiumPathSegment> PDFiumPageObject::getPathSegment(int index) return pPDFiumPathSegment; } +BitmapChecksum PDFiumPage::getChecksum() +{ + size_t nPageWidth = FPDF_GetPageWidth(mpPage); + size_t nPageHeight = FPDF_GetPageHeight(mpPage); + FPDF_BITMAP pPdfBitmap = FPDFBitmap_Create(nPageWidth, nPageHeight, /*alpha=*/1); + if (!pPdfBitmap) + { + return 0; + } + + // Intentionally not using FPDF_ANNOT here, annotations/commenting is OK to not affect the + // checksum, signature verification wants this. + FPDF_RenderPageBitmap(pPdfBitmap, mpPage, /*start_x=*/0, /*start_y=*/0, nPageWidth, nPageHeight, + /*rotate=*/0, /*flags=*/0); + Bitmap aBitmap(Size(nPageWidth, nPageHeight), 24); + { + BitmapScopedWriteAccess pWriteAccess(aBitmap); + const auto pPdfBuffer = static_cast<ConstScanline>(FPDFBitmap_GetBuffer(pPdfBitmap)); + const int nStride = FPDFBitmap_GetStride(pPdfBitmap); + for (size_t nRow = 0; nRow < nPageHeight; ++nRow) + { + ConstScanline pPdfLine = pPdfBuffer + (nStride * nRow); + pWriteAccess->CopyScanline(nRow, pPdfLine, ScanlineFormat::N32BitTcBgra, nStride); + } + } + return aBitmap.GetChecksum(); +} + PDFiumPathSegment::PDFiumPathSegment(FPDF_PATHSEGMENT pPathSegment) : mpPathSegment(pPathSegment) { |