diff options
Diffstat (limited to 'testenv/server/http/http_server.py')
| -rw-r--r-- | testenv/server/http/http_server.py | 492 |
1 files changed, 492 insertions, 0 deletions
diff --git a/testenv/server/http/http_server.py b/testenv/server/http/http_server.py new file mode 100644 index 0000000..6d8fc9e --- /dev/null +++ b/testenv/server/http/http_server.py @@ -0,0 +1,492 @@ +from http.server import HTTPServer, BaseHTTPRequestHandler +from exc.server_error import ServerError, AuthError, NoBodyServerError +from socketserver import BaseServer +from posixpath import basename, splitext +from base64 import b64encode +from random import random +from hashlib import md5 +import threading +import socket +import os + + +class StoppableHTTPServer(HTTPServer): + """ This class extends the HTTPServer class from default http.server library + in Python 3. The StoppableHTTPServer class is capable of starting an HTTP + server that serves a virtual set of files made by the WgetFile class and + has most of its properties configurable through the server_conf() + method. """ + + request_headers = list() + + """ Define methods for configuring the Server. """ + + def server_conf(self, filelist, conf_dict): + """ Set Server Rules and File System for this instance. """ + self.server_configs = conf_dict + self.fileSys = filelist + + def get_req_headers(self): + return self.request_headers + + +class HTTPSServer(StoppableHTTPServer): + """ The HTTPSServer class extends the StoppableHTTPServer class with + additional support for secure connections through SSL. """ + + def __init__(self, address, handler): + import ssl + BaseServer.__init__(self, address, handler) + # step one up because test suite change directory away from $srcdir + # (don't do that !!!) + CERTFILE = os.path.abspath(os.path.join('..', + os.getenv('srcdir', '.'), + 'certs', + 'server-cert.pem')) + KEYFILE = os.path.abspath(os.path.join('..', + os.getenv('srcdir', '.'), + 'certs', + 'server-key.pem')) + self.socket = ssl.wrap_socket( + sock=socket.socket(self.address_family, self.socket_type), + certfile=CERTFILE, + keyfile=KEYFILE, + server_side=True + ) + self.server_bind() + self.server_activate() + + +class _Handler(BaseHTTPRequestHandler): + """ This is a private class which tells the server *HOW* to handle each + request. For each HTTP Request Command that the server should be capable of + responding to, there must exist a do_REQUESTNAME() method which details the + steps in which such requests should be processed. The rest of the methods + in this class are auxiliary methods created to help in processing certain + requests. """ + + def get_rule_list(self, name): + return self.rules.get(name) + + # The defailt protocol version of the server we run is HTTP/1.1 not + # HTTP/1.0 which is the default with the http.server module. + protocol_version = 'HTTP/1.1' + + """ Define functions for various HTTP Requests. """ + + def do_HEAD(self): + self.send_head("HEAD") + + def do_GET(self): + """ Process HTTP GET requests. This is the same as processing HEAD + requests and then actually transmitting the data to the client. If + send_head() does not specify any "start" offset, we send the complete + data, else transmit only partial data. """ + + content, start = self.send_head("GET") + if content: + if start is None: + self.wfile.write(content.encode('utf-8')) + else: + self.wfile.write(content.encode('utf-8')[start:]) + + def do_POST(self): + """ According to RFC 7231 sec 4.3.3, if the resource requested in a POST + request does not exist on the server, the first POST request should + create that resource. PUT requests are otherwise used to create a + resource. Hence, we call the handle for processing PUT requests if the + resource requested does not already exist. + + Currently, when the server receives a POST request for a resource, we + simply append the body data to the existing file and return the new + file to the client. If the file does not exist, a new file is created + using the contents of the request body. """ + + path = self.path[1:] + if path in self.server.fileSys: + self.rules = self.server.server_configs.get(path) + if not self.rules: + self.rules = dict() + + if not self.custom_response(): + return(None, None) + + body_data = self.get_body_data() + self.send_response(200) + self.add_header("Content-type", "text/plain") + content = self.server.fileSys.pop(path) + "\n" + body_data + total_length = len(content) + self.server.fileSys[path] = content + self.add_header("Content-Length", total_length) + self.add_header("Location", self.path) + self.finish_headers() + try: + self.wfile.write(content.encode('utf-8')) + except Exception: + pass + else: + self.send_put(path) + + def do_PUT(self): + path = self.path[1:] + self.rules = self.server.server_configs.get(path) + if not self.custom_response(): + return(None, None) + self.send_put(path) + + """ End of HTTP Request Method Handlers. """ + + """ Helper functions for the Handlers. """ + + def parse_range_header(self, header_line, length): + import re + if header_line is None: + return None + if not header_line.startswith("bytes="): + raise ServerError("Cannot parse header Range: %s" % + (header_line)) + regex = re.match(r"^bytes=(\d*)\-$", header_line) + range_start = int(regex.group(1)) + if range_start >= length: + raise ServerError("Range Overflow") + return range_start + + def get_body_data(self): + cLength_header = self.headers.get("Content-Length") + cLength = int(cLength_header) if cLength_header is not None else 0 + body_data = self.rfile.read(cLength).decode('utf-8') + return body_data + + def send_put(self, path): + if path in self.server.fileSys: + self.server.fileSys.pop(path, None) + self.send_response(204) + else: + self.rules = dict() + self.send_response(201) + body_data = self.get_body_data() + self.server.fileSys[path] = body_data + self.add_header("Location", self.path) + self.finish_headers() + + """ This empty method is called automatically when all the rules are + processed for a given request. However, send_header() should only be called + AFTER a response has been sent. But, at the moment of processing the rules, + the appropriate response has not yet been identified. As a result, we defer + the processing of this rule till later. Each do_* request handler MUST call + finish_headers() instead of end_headers(). The finish_headers() method + takes care of sending the appropriate headers before completing the + response. """ + def SendHeader(self, header_obj): + pass + + def send_cust_headers(self): + header_obj = self.get_rule_list('SendHeader') + if header_obj: + for header in header_obj.headers: + self.add_header(header, header_obj.headers[header]) + + def finish_headers(self): + self.send_cust_headers() + try: + for keyword, value in self._headers_dict.items(): + if isinstance(value, list): + for value_el in value: + self.send_header(keyword, value_el) + else: + self.send_header(keyword, value) + # Clear the dictionary of existing headers for the next request + self._headers_dict.clear() + except AttributeError: + pass + self.end_headers() + + def Response(self, resp_obj): + self.send_response(resp_obj.response_code) + if resp_obj.response_code == 304: + raise NoBodyServerError("Conditional get falling to head") + raise ServerError("Custom Response code sent.") + + def custom_response(self): + codes = self.get_rule_list('Response') + if codes: + self.send_response(codes.response_code) + self.finish_headers() + return False + else: + return True + + def add_header(self, keyword, value): + if not hasattr(self, "_headers_dict"): + self._headers_dict = dict() + self._headers_dict[keyword.lower()] = value + + def base64(self, data): + string = b64encode(data.encode('utf-8')) + return string.decode('utf-8') + + """ Send an authentication challenge. + This method calls self.send_header() directly instead of using the + add_header() method because sending multiple WWW-Authenticate headers + actually makes sense and we do use that feature in some tests. """ + def send_challenge(self, auth_type, auth_parm): + auth_type = auth_type.lower() + if auth_type == "both": + self.send_challenge("basic", auth_parm) + self.send_challenge("digest", auth_parm) + return + if auth_type == "basic": + challenge_str = 'BasIc realm="Wget-Test"' + elif auth_type == "digest" or auth_type == "both_inline": + self.nonce = md5(str(random()).encode('utf-8')).hexdigest() + self.opaque = md5(str(random()).encode('utf-8')).hexdigest() + # 'DIgest' to provoke a Wget failure with turkish locales + challenge_str = 'DIgest realm="Test", nonce="%s", opaque="%s"' % ( + self.nonce, + self.opaque) + try: + if auth_parm['qop']: + challenge_str += ', qop="%s"' % auth_parm['qop'] + except KeyError: + pass + if auth_type == "both_inline": + # 'BasIc' to provoke a Wget failure with turkish locales + challenge_str = 'BasIc realm="Wget-Test", ' + challenge_str + self.send_header("WWW-Authenticate", challenge_str) + + def authorize_basic(self, auth_header, auth_rule): + if auth_header is None or auth_header.split(' ')[0].lower() != 'basic': + return False + else: + self.user = auth_rule.auth_user + self.passw = auth_rule.auth_pass + auth_str = "basic " + self.base64(self.user + ":" + self.passw) + return True if auth_str.lower() == auth_header.lower() else False + + def parse_auth_header(self, auth_header): + n = len("digest ") + auth_header = auth_header[n:].strip() + items = auth_header.split(", ") + keyvals = [i.split("=", 1) for i in items] + keyvals = [(k.strip(), v.strip().replace('"', '')) for k, v in keyvals] + return dict(keyvals) + + def KD(self, secret, data): + return self.H(secret + ":" + data) + + def H(self, data): + return md5(data.encode('utf-8')).hexdigest() + + def A1(self): + return "%s:%s:%s" % (self.user, "Test", self.passw) + + def A2(self, params): + return "%s:%s" % (self.command, params["uri"]) + + def check_response(self, params): + if "qop" in params: + data_str = params['nonce'] \ + + ":" + params['nc'] \ + + ":" + params['cnonce'] \ + + ":" + params['qop'] \ + + ":" + self.H(self.A2(params)) + else: + data_str = params['nonce'] + ":" + self.H(self.A2(params)) + resp = self.KD(self.H(self.A1()), data_str) + + return True if resp == params['response'] else False + + def authorize_digest(self, auth_header, auth_rule): + if auth_header is None or \ + auth_header.split(' ')[0].lower() != 'digest': + return False + else: + self.user = auth_rule.auth_user + self.passw = auth_rule.auth_pass + params = self.parse_auth_header(auth_header) + if self.user != params['username'] or \ + self.nonce != params['nonce'] or \ + self.opaque != params['opaque']: + return False + req_attribs = ['username', 'realm', 'nonce', 'uri', 'response'] + for attrib in req_attribs: + if attrib not in params: + return False + if not self.check_response(params): + return False + + def authorize_both(self, auth_header, auth_rule): + return False + + def authorize_both_inline(self, auth_header, auth_rule): + return False + + def Authentication(self, auth_rule): + try: + self.handle_auth(auth_rule) + except AuthError as se: + self.send_response(401, "Authorization Required") + self.send_challenge(auth_rule.auth_type, auth_rule.auth_parm) + raise se + + def handle_auth(self, auth_rule): + is_auth = True + auth_header = self.headers.get("Authorization") + required_auth = auth_rule.auth_type.lower() + if required_auth == "both" or required_auth == "both_inline": + if auth_header: + auth_type = auth_header.split(' ')[0].lower() + else: + auth_type = required_auth + else: + auth_type = required_auth + try: + assert hasattr(self, "authorize_" + auth_type) + is_auth = getattr(self, "authorize_" + auth_type)(auth_header, + auth_rule) + except AssertionError: + raise AuthError("Authentication Mechanism %s not supported" % + auth_type) + except AttributeError as ae: + raise AuthError(ae.__str__()) + if is_auth is False: + raise AuthError("Unable to Authenticate") + + def ExpectHeader(self, header_obj): + exp_headers = header_obj.headers + for header_line in exp_headers: + header_recd = self.headers.get(header_line) + if header_recd is None or header_recd != exp_headers[header_line]: + self.send_error(400, "Expected Header %s not found" % + header_line) + raise ServerError("Header " + header_line + " not found") + + def RejectHeader(self, header_obj): + rej_headers = header_obj.headers + for header_line in rej_headers: + header_recd = self.headers.get(header_line) + if header_recd and header_recd == rej_headers[header_line]: + self.send_error(400, 'Blacklisted Header %s received' % + header_line) + raise ServerError("Header " + header_line + ' received') + + def __log_request(self, method): + req = method + " " + self.path + self.server.request_headers.append(req) + + def send_head(self, method): + """ Common code for GET and HEAD Commands. + This method is overridden to use the fileSys dict. + + The method variable contains whether this was a HEAD or a GET Request. + According to RFC 2616, the server should not differentiate between + the two requests, however, we use it here for a specific test. + """ + + if self.path == "/": + path = "index.html" + else: + path = self.path[1:] + + self.__log_request(method) + + if path in self.server.fileSys: + self.rules = self.server.server_configs.get(path) + + content = self.server.fileSys.get(path) + content_length = len(content) + + for rule_name in self.rules: + try: + assert hasattr(self, rule_name) + getattr(self, rule_name)(self.rules[rule_name]) + except AssertionError as ae: + msg = "Rule " + rule_name + " not defined" + self.send_error(500, msg) + return(None, None) + except AuthError as ae: + print(ae.__str__()) + self.finish_headers() + return(None, None) + except NoBodyServerError as nbse: + print(nbse.__str__()) + self.finish_headers() + return(None, None) + except ServerError as se: + print(se.__str__()) + self.add_header("Content-Length", content_length) + self.finish_headers() + return(content, None) + + try: + self.range_begin = self.parse_range_header( + self.headers.get("Range"), content_length) + except ServerError as ae: + # self.log_error("%s", ae.err_message) + if ae.err_message == "Range Overflow": + try: + self.overflows += 1 + except AttributeError as s: + self.overflows = 0 + self.send_response(416) + if self.overflows > 0: + self.add_header("Content-Length", 17) + self.finish_headers() + if self.overflows > 0: + return("Range Unsatisfied", 0) + return(None, None) + else: + self.range_begin = None + if self.range_begin is None: + self.send_response(200) + else: + self.send_response(206) + self.add_header("Accept-Ranges", "bytes") + self.add_header("Content-Range", + "bytes %d-%d/%d" % (self.range_begin, + content_length - 1, + content_length)) + content_length -= self.range_begin + cont_type = self.guess_type(path) + self.add_header("Content-Type", cont_type) + self.add_header("Content-Length", content_length) + self.finish_headers() + return(content, self.range_begin) + else: + self.send_error(404, "Not Found") + return(None, None) + + def guess_type(self, path): + base_name = basename("/" + path) + name, ext = splitext(base_name) + extension_map = { + ".txt": "text/plain", + ".css": "text/css", + ".html": "text/html" + } + return extension_map.get(ext, "text/plain") + + +class HTTPd(threading.Thread): + server_class = StoppableHTTPServer + handler = _Handler + + def __init__(self, addr=None): + threading.Thread.__init__(self) + if addr is None: + addr = ('localhost', 0) + self.server_inst = self.server_class(addr, self.handler) + self.server_address = self.server_inst.socket.getsockname()[:2] + + def run(self): + self.server_inst.serve_forever() + + def server_conf(self, file_list, server_rules): + self.server_inst.server_conf(file_list, server_rules) + + +class HTTPSd(HTTPd): + + server_class = HTTPSServer + +# vim: set ts=4 sts=4 sw=4 tw=79 et : |