# $Id: http.py 86 2013-03-05 19:25:19Z andrewflnr@gmail.com $
# -*- coding: utf-8 -*-
"""Hypertext Transfer Protocol."""
import cStringIO
import dpkt
[docs]def parse_body(f, headers):
"""Return HTTP body parsed from a file object, given HTTP header dict."""
if headers.get('transfer-encoding', '').lower() == 'chunked':
l = []
found_end = False
while 1:
try:
sz = f.readline().split(None, 1)[0]
except IndexError:
raise dpkt.UnpackError('missing chunk size')
n = int(sz, 16)
if n == 0:
found_end = True
buf = f.read(n)
if f.readline().strip():
break
if n and len(buf) == n:
l.append(buf)
else:
break
if not found_end:
raise dpkt.NeedData('premature end of chunked body')
body = ''.join(l)
elif 'content-length' in headers:
n = int(headers['content-length'])
body = f.read(n)
if len(body) != n:
raise dpkt.NeedData('short body (missing %d bytes)' % (n - len(body)))
elif 'content-type' in headers:
body = f.read()
else:
# XXX - need to handle HTTP/0.9
body = ''
return body
[docs]class Message(dpkt.Packet):
"""Hypertext Transfer Protocol headers + body.
TODO: Longer class information....
Attributes:
__hdr__: Header fields of HTTP.
TODO.
"""
__metaclass__ = type
__hdr_defaults__ = {}
headers = None
body = None
def __init__(self, *args, **kwargs):
if args:
self.unpack(args[0])
else:
self.headers = {}
self.body = ''
for k, v in self.__hdr_defaults__.iteritems():
setattr(self, k, v)
for k, v in kwargs.iteritems():
setattr(self, k, v)
[docs] def unpack(self, buf, is_body_allowed = True):
f = cStringIO.StringIO(buf)
# Parse headers
self.headers = parse_headers(f)
# Parse body
if is_body_allowed:
self.body = parse_body(f, self.headers)
# Save the rest
self.data = f.read()
[docs] def pack_hdr(self):
return ''.join(['%s: %s\r\n' % t for t in self.headers.iteritems()])
def __len__(self):
return len(str(self))
def __str__(self):
return '%s\r\n%s' % (self.pack_hdr(), self.body)
[docs]class Request(Message):
"""Hypertext Transfer Protocol Request.
TODO: Longer class information....
Attributes:
__hdr__: Header fields of HTTP request.
TODO.
"""
__hdr_defaults__ = {
'method': 'GET',
'uri': '/',
'version': '1.0',
}
__methods = dict.fromkeys((
'GET', 'PUT', 'ICY',
'COPY', 'HEAD', 'LOCK', 'MOVE', 'POLL', 'POST',
'BCOPY', 'BMOVE', 'MKCOL', 'TRACE', 'LABEL', 'MERGE',
'DELETE', 'SEARCH', 'UNLOCK', 'REPORT', 'UPDATE', 'NOTIFY',
'BDELETE', 'CONNECT', 'OPTIONS', 'CHECKIN',
'PROPFIND', 'CHECKOUT', 'CCM_POST',
'SUBSCRIBE', 'PROPPATCH', 'BPROPFIND',
'BPROPPATCH', 'UNCHECKOUT', 'MKACTIVITY',
'MKWORKSPACE', 'UNSUBSCRIBE', 'RPC_CONNECT',
'VERSION-CONTROL',
'BASELINE-CONTROL'
))
__proto = 'HTTP'
[docs] def unpack(self, buf):
f = cStringIO.StringIO(buf)
line = f.readline()
l = line.strip().split()
if len(l) < 2:
raise dpkt.UnpackError('invalid request: %r' % line)
if l[0] not in self.__methods:
raise dpkt.UnpackError('invalid http method: %r' % l[0])
if len(l) == 2:
# HTTP/0.9 does not specify a version in the request line
self.version = '0.9'
else:
if not l[2].startswith(self.__proto):
raise dpkt.UnpackError('invalid http version: %r' % l[2])
self.version = l[2][len(self.__proto) + 1:]
self.method = l[0]
self.uri = l[1]
Message.unpack(self, f.read())
def __str__(self):
return '%s %s %s/%s\r\n' % (self.method, self.uri, self.__proto,
self.version) + Message.__str__(self)
[docs]class Response(Message):
"""Hypertext Transfer Protocol Response.
TODO: Longer class information....
Attributes:
__hdr__: Header fields of HTTP Response.
TODO.
"""
__hdr_defaults__ = {
'version': '1.0',
'status': '200',
'reason': 'OK'
}
__proto = 'HTTP'
[docs] def unpack(self, buf):
f = cStringIO.StringIO(buf)
line = f.readline()
l = line.strip().split(None, 2)
if len(l) < 2 or not l[0].startswith(self.__proto) or not l[1].isdigit():
raise dpkt.UnpackError('invalid response: %r' % line)
self.version = l[0][len(self.__proto) + 1:]
self.status = l[1]
self.reason = l[2] if len(l) > 2 else ''
# RFC Sec 4.3.
# http://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.3.
# For response messages, whether or not a message-body is included with
# a message is dependent on both the request method and the response
# status code (section 6.1.1). All responses to the HEAD request method
# MUST NOT include a message-body, even though the presence of entity-
# header fields might lead one to believe they do. All 1xx
# (informational), 204 (no content), and 304 (not modified) responses
# MUST NOT include a message-body. All other responses do include a
# message-body, although it MAY be of zero length.
is_body_allowed = int(self.status) >= 200 and 204 != int(self.status) != 304
Message.unpack(self, f.read(), is_body_allowed)
def __str__(self):
return '%s/%s %s %s\r\n' % (self.__proto, self.version, self.status,
self.reason) + Message.__str__(self)
[docs]def test_parse_request():
s = """POST /main/redirect/ab/1,295,,00.html HTTP/1.0\r\nReferer: http://www.email.com/login/snap/login.jhtml\r\nConnection: Keep-Alive\r\nUser-Agent: Mozilla/4.75 [en] (X11; U; OpenBSD 2.8 i386; Nav)\r\nHost: ltd.snap.com\r\nAccept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, image/png, */*\r\nAccept-Encoding: gzip\r\nAccept-Language: en\r\nAccept-Charset: iso-8859-1,*,utf-8\r\nContent-type: application/x-www-form-urlencoded\r\nContent-length: 61\r\n\r\nsn=em&mn=dtest4&pw=this+is+atest&fr=true&login=Sign+in&od=www"""
r = Request(s)
assert r.method == 'POST'
assert r.uri == '/main/redirect/ab/1,295,,00.html'
assert r.body == 'sn=em&mn=dtest4&pw=this+is+atest&fr=true&login=Sign+in&od=www'
assert r.headers['content-type'] == 'application/x-www-form-urlencoded'
try:
Request(s[:60])
assert 'invalid headers parsed!'
except dpkt.UnpackError:
pass
[docs]def test_chunked_response():
s = """HTTP/1.1 200 OK\r\nCache-control: no-cache\r\nPragma: no-cache\r\nContent-Type: text/javascript; charset=utf-8\r\nContent-Encoding: gzip\r\nTransfer-Encoding: chunked\r\nSet-Cookie: S=gmail=agg:gmail_yj=v2s:gmproxy=JkU; Domain=.google.com; Path=/\r\nServer: GFE/1.3\r\nDate: Mon, 12 Dec 2005 22:33:23 GMT\r\n\r\na\r\n\x1f\x8b\x08\x00\x00\x00\x00\x00\x00\x00\r\n152\r\nm\x91MO\xc4 \x10\x86\xef\xfe\n\x82\xc9\x9eXJK\xe9\xb6\xee\xc1\xe8\x1e6\x9e4\xf1\xe0a5\x86R\xda\x12Yh\x80\xba\xfa\xef\x85\xee\x1a/\xf21\x99\x0c\xef0<\xc3\x81\xa0\xc3\x01\xe6\x10\xc1<\xa7eYT5\xa1\xa4\xac\xe1\xdb\x15:\xa4\x9d\x0c\xfa5K\x00\xf6.\xaa\xeb\x86\xd5y\xcdHY\x954\x8e\xbc*h\x8c\x8e!L7Y\xe6\'\xeb\x82WZ\xcf>8\x1ed\x87\x851X\xd8c\xe6\xbc\x17Z\x89\x8f\xac \x84e\xde\n!]\x96\x17i\xb5\x02{{\xc2z0\x1e\x0f#7\x9cw3v\x992\x9d\xfc\xc2c8\xea[/EP\xd6\xbc\xce\x84\xd0\xce\xab\xf7`\'\x1f\xacS\xd2\xc7\xd2\xfb\x94\x02N\xdc\x04\x0f\xee\xba\x19X\x03TtW\xd7\xb4\xd9\x92\n\xbcX\xa7;\xb0\x9b\'\x10$?F\xfd\xf3CzPt\x8aU\xef\xb8\xc8\x8b-\x18\xed\xec<\xe0\x83\x85\x08!\xf8"[\xb0\xd3j\x82h\x93\xb8\xcf\xd8\x9b\xba\xda\xd0\x92\x14\xa4a\rc\reM\xfd\x87=X;h\xd9j;\xe0db\x17\xc2\x02\xbd\xb0F\xc2in#\xfb:\xb6\xc4x\x15\xd6\x9f\x8a\xaf\xcf)\x0b^\xbc\xe7i\x11\x80\x8b\x00D\x01\xd8/\x82x\xf6\xd8\xf7J(\xae/\x11p\x1f+\xc4p\t:\xfe\xfd\xdf\xa3Y\xfa\xae4\x7f\x00\xc5\xa5\x95\xa1\xe2\x01\x00\x00\r\n0\r\n\r\n"""
r = Response(s)
assert r.version == '1.1'
assert r.status == '200'
assert r.reason == 'OK'
[docs]def test_multicookie_response():
s = """HTTP/1.x 200 OK\r\nSet-Cookie: first_cookie=cookie1; path=/; domain=.example.com\r\nSet-Cookie: second_cookie=cookie2; path=/; domain=.example.com\r\nContent-Length: 0\r\n\r\n"""
r = Response(s)
assert type(r.headers['set-cookie']) is list
assert len(r.headers['set-cookie']) == 2
[docs]def test_noreason_response():
s = """HTTP/1.1 200 \r\n\r\n"""
r = Response(s)
assert r.reason == ''
assert str(r) == s
[docs]def test_body_forbidden_response():
s = 'HTTP/1.1 304 Not Modified\r\n'\
'Content-Type: text/css\r\n'\
'Last-Modified: Wed, 14 Jan 2009 16:42:11 GMT\r\n'\
'ETag: "3a7-496e15e3"\r\n'\
'Cache-Control: private, max-age=414295\r\n'\
'Date: Wed, 22 Sep 2010 17:55:54 GMT\r\n'\
'Connection: keep-alive\r\n'\
'Vary: Accept-Encoding\r\n\r\n'\
'HTTP/1.1 200 OK\r\n'\
'Server: Sun-ONE-Web-Server/6.1\r\n'\
'ntCoent-length: 257\r\n'\
'Content-Type: application/x-javascript\r\n'\
'Last-Modified: Wed, 06 Jan 2010 19:34:06 GMT\r\n'\
'ETag: "101-4b44e5ae"\r\n'\
'Accept-Ranges: bytes\r\n'\
'Content-Encoding: gzip\r\n'\
'Cache-Control: private, max-age=439726\r\n'\
'Date: Wed, 22 Sep 2010 17:55:54 GMT\r\n'\
'Connection: keep-alive\r\n'\
'Vary: Accept-Encoding\r\n'
result = []
while s:
msg = Response(s)
s = msg.data
result.append(msg)
# the second HTTP response should be an standalone message
assert len(result) == 2
[docs]def test_request_version():
s = """GET / HTTP/1.0\r\n\r\n"""
r = Request(s)
assert r.method == 'GET'
assert r.uri == '/'
assert r.version == '1.0'
s = """GET /\r\n\r\n"""
r = Request(s)
assert r.method == 'GET'
assert r.uri == '/'
assert r.version == '0.9'
s = """GET / CHEESE/1.0\r\n\r\n"""
try:
Request(s)
assert "invalid protocol version parsed!"
except:
pass
if __name__ == '__main__':
# Runs all the test associated with this class/file
test_parse_request()
test_format_request()
test_chunked_response()
test_multicookie_response()
test_noreason_response()
test_request_version()
test_invalid_header()
test_body_forbidden_response()
print 'Tests Successful...'