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
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
|
# Copyright (C) 2009-2010 Canonical Ltd.
#
# Author: Scott Moser <scott.moser@canonical.com>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 3, as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
import email
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText
starts_with_mappings={
'#include' : 'text/x-include-url',
'#!' : 'text/x-shellscript',
'#cloud-config' : 'text/cloud-config',
'#upstart-job' : 'text/upstart-job',
'#part-handler' : 'text/part-handler'
}
# if 'str' is compressed return decompressed otherwise return it
def decomp_str(str):
import StringIO
import gzip
try:
uncomp = gzip.GzipFile(None,"rb",1,StringIO.StringIO(str)).read()
return(uncomp)
except:
return(str)
def do_include(str,parts):
import urllib
# is just a list of urls, one per line
for line in str.splitlines():
if line == "#include": continue
if line.startswith("#"): continue
content = urllib.urlopen(line).read()
process_includes(email.message_from_string(decomp_str(content)),parts)
def process_includes(msg,parts):
# parts is a dictionary of arrays
# parts['content']
# parts['names']
# parts['types']
for t in ( 'content', 'names', 'types' ):
if not parts.has_key(t):
parts[t]=[ ]
for part in msg.walk():
# multipart/* are just containers
if part.get_content_maintype() == 'multipart':
continue
payload = part.get_payload()
ctype = None
for str, gtype in starts_with_mappings.items():
if payload.startswith(str):
ctype = gtype
break
if ctype is None:
ctype = part.get_content_type()
if ctype == 'text/x-include-url':
do_include(payload,parts)
continue
filename = part.get_filename()
if not filename:
filename = 'part-%03d' % len(parts['content'])
parts['content'].append(payload)
parts['types'].append(ctype)
parts['names'].append(filename)
def parts2mime(parts):
outer = MIMEMultipart()
i = 0
while i < len(parts['content']):
if parts['types'][i] is None:
# No guess could be made, or the file is encoded (compressed), so
# use a generic bag-of-bits type.
ctype = 'application/octet-stream'
else: ctype = parts['types'][i]
maintype, subtype = ctype.split('/', 1)
if maintype == 'text':
msg = MIMEText(parts['content'][i], _subtype=subtype)
else:
msg = MIMEBase(maintype, subtype)
msg.set_payload(parts['content'][i])
# Encode the payload using Base64
encoders.encode_base64(msg)
# Set the filename parameter
msg.add_header('Content-Disposition', 'attachment',
filename=parts['names'][i])
outer.attach(msg)
i=i+1
return(outer.as_string())
# this is heavily wasteful, reads through userdata string input
def preprocess_userdata(data):
parts = { }
process_includes(email.message_from_string(decomp_str(data)),parts)
return(parts2mime(parts))
# callbacks is a dictionary with:
# { 'content-type': handler(data,content_type,filename,payload) }
def walk_userdata(str, callbacks, data = None):
partnum = 0
for part in email.message_from_string(str).walk():
# multipart/* are just containers
if part.get_content_maintype() == 'multipart':
continue
ctype = part.get_content_type()
if ctype is None:
ctype = 'application/octet-stream'
filename = part.get_filename()
if not filename:
filename = 'part-%03d' % partnum
if callbacks.has_key(ctype):
callbacks[ctype](data,ctype,filename,part.get_payload())
partnum = partnum+1
if __name__ == "__main__":
import sys
data = decomp_str(file(sys.argv[1]).read())
parts = { }
process_includes(email.message_from_string(data),parts)
print "#found %s parts" % len(parts['content'])
print parts2mime(parts)
|