1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
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)
|
