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Diffstat (limited to 'PolyglotFile/polyglotszippdf.py')
-rw-r--r-- | PolyglotFile/polyglotszippdf.py | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/PolyglotFile/polyglotszippdf.py b/PolyglotFile/polyglotszippdf.py new file mode 100644 index 0000000..0796946 --- /dev/null +++ b/PolyglotFile/polyglotszippdf.py @@ -0,0 +1,110 @@ +# -*- coding: utf-8 -*- + +from .polyglotpdfzip import PolyglotPdfZip +import logging +import tempfile +from ZipFileTransformer import ZipFile +from ZipFileTransformer import Zip +from PdfFileTransformer import Pdf + +''' + |-----------------------------------| - + |--------- ZIP Data[0] = -----------| | + |- PDF Header + PDF Obj[0] Header --| | + |-----------------------------------| | K2 + |------- PDF Obj[0] stream = ------| | + |--------- ZIP Data LF [1:] --------| | + |-----------------------------------| - + |------ Original PDF Ojbects -------| | + |-----------------------------------| | + |------------ Xref Table -----------| | + |-----------------------------------| | J2 + |------------- Trailer -------------| | + |-----------------------------------| - + |---------- End Zip Data -----------| + |-----------------------------------| +''' + + +class PolyglotSZipPdf(PolyglotPdfZip): + + def __init__(self, Pdf, Zip): + super().__init__(Pdf, Zip) + + def get_rebuild_zip_first_part_size(self): + + zo_path = tempfile.mkstemp()[1] + logging.info("use tmp file zip: " + zo_path) + zo = ZipFile(zo_path, 'a') + zi = ZipFile(self.zip.filename, 'r') + for zipinfo in zi.infolist(): + zo.writestr(zipinfo, zi.read(zipinfo)) + zi.close() + zo.close() + + rebuild_zip = Zip(zo_path) + + p = rebuild_zip.end_of_data + k2_stream = rebuild_zip.buffer[:p] + + size_k2_stream = len(k2_stream) + + return size_k2_stream + + def get_pdf_header(self): + return self.pdf.get_file_header() + + def generate_zip_with_pdf_part(self, filename, pdf_data): + + zo = ZipFile(filename, 'a') + zi = ZipFile(self.zip.filename, 'r') + zo.writestr(' ', pdf_data, 0) + for zipinfo in zi.infolist(): + zo.writestr(zipinfo, zi.read(zipinfo)) + zi.close() + zo.close() + + def get_rebuild_pdf(self, zo_path, offset): + ''' + Generate polyglot with final zip. + ''' + new_zip = Zip(zo_path) + new_pdf = Pdf(self.pdf.filename) + + p1 = new_zip.end_of_first_local_file_header + p2 = new_zip.end_of_data + k2_stream = new_zip.buffer[p1:p2] + + size_k2_stream = len(k2_stream) + new_pdf.insert_new_obj_stream_at_start(k2_stream) + k2_stream_offset = new_pdf.get_first_stream_offset() + + new_pdf.file_offset = offset + pdf_buffer = new_pdf.get_build_buffer() + j2 = pdf_buffer[k2_stream_offset + size_k2_stream:] + new_zip.add_data_to_file(b'', j2, True) + + return new_zip.buffer + + def get_pdf_offset(self, zipfile): + + f = open(zipfile, "rb") + data = f.read() + return data.find(b"%PDF") + + def generate(self): + + zip_stream_size = self.get_rebuild_zip_first_part_size() + pdf_header = self.get_pdf_header() + pdf_header = (pdf_header + + b'1 0 obj\n<<\n/Filter /FlateDecode\n/Length ' + + str(zip_stream_size).encode("utf-8") + + b'\n>>\nstream\n') + + filename = tempfile.mkstemp()[1] + logging.info("use tmp file for new zip: " + filename) + self.generate_zip_with_pdf_part(filename, pdf_header) + + pdf_offset = self.get_pdf_offset(filename) + + self.buffer = self.get_rebuild_pdf(filename, pdf_offset) |