/usr/lib/python3/dist-packages/waitress/parser.py is in python3-waitress 1.0.1-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 | ##############################################################################
#
# Copyright (c) 2001, 2002 Zope Foundation and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL). A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
"""HTTP Request Parser
This server uses asyncore to accept connections and do initial
processing but threads to do work.
"""
import re
from io import BytesIO
from waitress.compat import (
tostr,
urlparse,
unquote_bytes_to_wsgi,
)
from waitress.buffers import OverflowableBuffer
from waitress.receiver import (
FixedStreamReceiver,
ChunkedReceiver,
)
from waitress.utilities import (
find_double_newline,
RequestEntityTooLarge,
RequestHeaderFieldsTooLarge,
BadRequest,
)
class ParsingError(Exception):
pass
class HTTPRequestParser(object):
"""A structure that collects the HTTP request.
Once the stream is completed, the instance is passed to
a server task constructor.
"""
completed = False # Set once request is completed.
empty = False # Set if no request was made.
expect_continue = False # client sent "Expect: 100-continue" header
headers_finished = False # True when headers have been read
header_plus = b''
chunked = False
content_length = 0
header_bytes_received = 0
body_bytes_received = 0
body_rcv = None
version = '1.0'
error = None
connection_close = False
# Other attributes: first_line, header, headers, command, uri, version,
# path, query, fragment
def __init__(self, adj):
"""
adj is an Adjustments object.
"""
# headers is a mapping containing keys translated to uppercase
# with dashes turned into underscores.
self.headers = {}
self.adj = adj
def received(self, data):
"""
Receives the HTTP stream for one request. Returns the number of
bytes consumed. Sets the completed flag once both the header and the
body have been received.
"""
if self.completed:
return 0 # Can't consume any more.
datalen = len(data)
br = self.body_rcv
if br is None:
# In header.
s = self.header_plus + data
index = find_double_newline(s)
if index >= 0:
# Header finished.
header_plus = s[:index]
consumed = len(data) - (len(s) - index)
# Remove preceeding blank lines.
header_plus = header_plus.lstrip()
if not header_plus:
self.empty = True
self.completed = True
else:
try:
self.parse_header(header_plus)
except ParsingError as e:
self.error = BadRequest(e.args[0])
self.completed = True
else:
if self.body_rcv is None:
# no content-length header and not a t-e: chunked
# request
self.completed = True
if self.content_length > 0:
max_body = self.adj.max_request_body_size
# we won't accept this request if the content-length
# is too large
if self.content_length >= max_body:
self.error = RequestEntityTooLarge(
'exceeds max_body of %s' % max_body)
self.completed = True
self.headers_finished = True
return consumed
else:
# Header not finished yet.
self.header_bytes_received += datalen
max_header = self.adj.max_request_header_size
if self.header_bytes_received >= max_header:
# malformed header, we need to construct some request
# on our own. we disregard the incoming(?) requests HTTP
# version and just use 1.0. IOW someone just sent garbage
# over the wire
self.parse_header(b'GET / HTTP/1.0\n')
self.error = RequestHeaderFieldsTooLarge(
'exceeds max_header of %s' % max_header)
self.completed = True
self.header_plus = s
return datalen
else:
# In body.
consumed = br.received(data)
self.body_bytes_received += consumed
max_body = self.adj.max_request_body_size
if self.body_bytes_received >= max_body:
# this will only be raised during t-e: chunked requests
self.error = RequestEntityTooLarge(
'exceeds max_body of %s' % max_body)
self.completed = True
elif br.error:
# garbage in chunked encoding input probably
self.error = br.error
self.completed = True
elif br.completed:
# The request (with the body) is ready to use.
self.completed = True
if self.chunked:
# We've converted the chunked transfer encoding request
# body into a normal request body, so we know its content
# length; set the header here. We already popped the
# TRANSFER_ENCODING header in parse_header, so this will
# appear to the client to be an entirely non-chunked HTTP
# request with a valid content-length.
self.headers['CONTENT_LENGTH'] = str(br.__len__())
return consumed
def parse_header(self, header_plus):
"""
Parses the header_plus block of text (the headers plus the
first line of the request).
"""
index = header_plus.find(b'\n')
if index >= 0:
first_line = header_plus[:index].rstrip()
header = header_plus[index + 1:]
else:
first_line = header_plus.rstrip()
header = b''
self.first_line = first_line # for testing
lines = get_header_lines(header)
headers = self.headers
for line in lines:
index = line.find(b':')
if index > 0:
key = line[:index]
if b'_' in key:
continue
value = line[index + 1:].strip()
key1 = tostr(key.upper().replace(b'-', b'_'))
# If a header already exists, we append subsequent values
# seperated by a comma. Applications already need to handle
# the comma seperated values, as HTTP front ends might do
# the concatenation for you (behavior specified in RFC2616).
try:
headers[key1] += tostr(b', ' + value)
except KeyError:
headers[key1] = tostr(value)
# else there's garbage in the headers?
# command, uri, version will be bytes
command, uri, version = crack_first_line(first_line)
version = tostr(version)
command = tostr(command)
self.command = command
self.version = version
(self.proxy_scheme,
self.proxy_netloc,
self.path,
self.query, self.fragment) = split_uri(uri)
self.url_scheme = self.adj.url_scheme
connection = headers.get('CONNECTION', '')
if version == '1.0':
if connection.lower() != 'keep-alive':
self.connection_close = True
if version == '1.1':
# since the server buffers data from chunked transfers and clients
# never need to deal with chunked requests, downstream clients
# should not see the HTTP_TRANSFER_ENCODING header; we pop it
# here
te = headers.pop('TRANSFER_ENCODING', '')
if te.lower() == 'chunked':
self.chunked = True
buf = OverflowableBuffer(self.adj.inbuf_overflow)
self.body_rcv = ChunkedReceiver(buf)
expect = headers.get('EXPECT', '').lower()
self.expect_continue = expect == '100-continue'
if connection.lower() == 'close':
self.connection_close = True
if not self.chunked:
try:
cl = int(headers.get('CONTENT_LENGTH', 0))
except ValueError:
cl = 0
self.content_length = cl
if cl > 0:
buf = OverflowableBuffer(self.adj.inbuf_overflow)
self.body_rcv = FixedStreamReceiver(cl, buf)
def get_body_stream(self):
body_rcv = self.body_rcv
if body_rcv is not None:
return body_rcv.getfile()
else:
return BytesIO()
def close(self):
body_rcv = self.body_rcv
if body_rcv is not None:
body_rcv.getbuf().close()
def split_uri(uri):
# urlsplit handles byte input by returning bytes on py3, so
# scheme, netloc, path, query, and fragment are bytes
scheme, netloc, path, query, fragment = urlparse.urlsplit(uri)
return (
tostr(scheme),
tostr(netloc),
unquote_bytes_to_wsgi(path),
tostr(query),
tostr(fragment),
)
def get_header_lines(header):
"""
Splits the header into lines, putting multi-line headers together.
"""
r = []
lines = header.split(b'\n')
for line in lines:
if line.startswith((b' ', b'\t')):
if not r:
# http://corte.si/posts/code/pathod/pythonservers/index.html
raise ParsingError('Malformed header line "%s"' % tostr(line))
r[-1] += line
else:
r.append(line)
return r
first_line_re = re.compile(
b'([^ ]+) '
b'((?:[^ :?#]+://[^ ?#/]*(?:[0-9]{1,5})?)?[^ ]+)'
b'(( HTTP/([0-9.]+))$|$)'
)
def crack_first_line(line):
m = first_line_re.match(line)
if m is not None and m.end() == len(line):
if m.group(3):
version = m.group(5)
else:
version = None
command = m.group(1).upper()
uri = m.group(2)
return command, uri, version
else:
return b'', b'', b''
|