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), ssl_version=ssl.PROTOCOL_TLSv1, 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 auxilliary 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 recieves 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(): 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) self.finish_headers() 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_type = auth_type.lower() if auth_type == "both": self.send_challenge("basic") self.send_challenge("digest") 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) challenge_str += ', qop="auth"' 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) self.finish_headers() 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) self.finish_headers() 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 not header_recd and header_recd == rej_headers[header_line]: self.send_error(400, 'Blacklisted Header %s received' % header_line) self.finish_headers() 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 overriden 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__()) return(None, None) except NoBodyServerError as nbse: print(nbse.__str__()) return(None, None) except ServerError as se: print(se.__str__()) 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": self.send_response(416) self.finish_headers() 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 :