X-Git-Url: https://git.mxchange.org/?a=blobdiff_plain;f=apt_dht_Khashmir%2Fkrpc.py;h=14000309ceaf441a4261706f29803e6d5803c29d;hb=e707ea9bffe22e6b0b5ace503c11d4f551aa16a2;hp=1428545430c104a20fc729e5d042715436295a5f;hpb=3d6c833df60bcae0bb3aa809ea8c5813289e97f1;p=quix0rs-apt-p2p.git diff --git a/apt_dht_Khashmir/krpc.py b/apt_dht_Khashmir/krpc.py index 1428545..1400030 100644 --- a/apt_dht_Khashmir/krpc.py +++ b/apt_dht_Khashmir/krpc.py @@ -3,8 +3,7 @@ from bencode import bencode, bdecode from time import asctime -import sys -from traceback import format_exception +from math import ceil from twisted.internet.defer import Deferred from twisted.internet import protocol, reactor @@ -14,11 +13,22 @@ from twisted.trial import unittest from khash import newID KRPC_TIMEOUT = 20 +UDP_PACKET_LIMIT = 1472 -KRPC_ERROR = 1 -KRPC_ERROR_METHOD_UNKNOWN = 2 -KRPC_ERROR_RECEIVED_UNKNOWN = 3 -KRPC_ERROR_TIMEOUT = 4 +# Remote node errors +KRPC_ERROR = 200 +KRPC_ERROR_SERVER_ERROR = 201 +KRPC_ERROR_MALFORMED_PACKET = 202 +KRPC_ERROR_METHOD_UNKNOWN = 203 +KRPC_ERROR_MALFORMED_REQUEST = 204 +KRPC_ERROR_INVALID_TOKEN = 205 +KRPC_ERROR_RESPONSE_TOO_LONG = 206 + +# Local errors +KRPC_ERROR_INTERNAL = 100 +KRPC_ERROR_RECEIVED_UNKNOWN = 101 +KRPC_ERROR_TIMEOUT = 102 +KRPC_ERROR_PROTOCOL_STOPPED = 103 # commands TID = 't' @@ -28,9 +38,53 @@ TYP = 'y' ARG = 'a' ERR = 'e' -class ProtocolError(Exception): +class KrpcError(Exception): pass +def verifyMessage(msg): + """Check received message for corruption and errors. + + @type msg: C{dictionary} + @param msg: the dictionary of information received on the connection + @raise KrpcError: if the message is corrupt + """ + + if type(msg) != dict: + raise KrpcError, (KRPC_ERROR_MALFORMED_PACKET, "not a dictionary") + if TYP not in msg: + raise KrpcError, (KRPC_ERROR_MALFORMED_PACKET, "no message type") + if msg[TYP] == REQ: + if REQ not in msg: + raise KrpcError, (KRPC_ERROR_MALFORMED_PACKET, "request type not specified") + if type(msg[REQ]) != str: + raise KrpcError, (KRPC_ERROR_MALFORMED_PACKET, "request type is not a string") + if ARG not in msg: + raise KrpcError, (KRPC_ERROR_MALFORMED_PACKET, "no arguments for request") + if type(msg[ARG]) != dict: + raise KrpcError, (KRPC_ERROR_MALFORMED_PACKET, "arguments for request are not in a dictionary") + elif msg[TYP] == RSP: + if RSP not in msg: + raise KrpcError, (KRPC_ERROR_MALFORMED_PACKET, "response not specified") + if type(msg[RSP]) != dict: + raise KrpcError, (KRPC_ERROR_MALFORMED_PACKET, "response is not a dictionary") + elif msg[TYP] == ERR: + if ERR not in msg: + raise KrpcError, (KRPC_ERROR_MALFORMED_PACKET, "error not specified") + if type(msg[ERR]) != list: + raise KrpcError, (KRPC_ERROR_MALFORMED_PACKET, "error is not a list") + if len(msg[ERR]) != 2: + raise KrpcError, (KRPC_ERROR_MALFORMED_PACKET, "error is not a 2-element list") + if type(msg[ERR][0]) not in (int, long): + raise KrpcError, (KRPC_ERROR_MALFORMED_PACKET, "error number is not a number") + if type(msg[ERR][1]) != str: + raise KrpcError, (KRPC_ERROR_MALFORMED_PACKET, "error string is not a string") +# else: +# raise KrpcError, (KRPC_ERROR_MALFORMED_PACKET, "unknown message type") + if TID not in msg: + raise KrpcError, (KRPC_ERROR_MALFORMED_PACKET, "no transaction ID specified") + if type(msg[TID]) != str: + raise KrpcError, (KRPC_ERROR_MALFORMED_PACKET, "transaction id is not a string") + class hostbroker(protocol.DatagramProtocol): def __init__(self, server, config): self.server = server @@ -76,117 +130,183 @@ class KRPC: self.tids = {} self.stopped = False - def datagramReceived(self, str, addr): + def datagramReceived(self, data, addr): if self.stopped: if self.noisy: - log.msg("stopped, dropping message from %r: %s" % (addr, str)) + log.msg("stopped, dropping message from %r: %s" % (addr, data)) # bdecode try: - msg = bdecode(str) + msg = bdecode(data) except Exception, e: if self.noisy: - log.msg("response decode error: ") + log.msg("krpc bdecode error: ") log.err(e) - else: - if self.noisy: - log.msg("%d received from %r: %s" % (self.factory.port, addr, msg)) - # look at msg type - if msg[TYP] == REQ: - ilen = len(str) - # if request - # tell factory to handle - f = getattr(self.factory ,"krpc_" + msg[REQ], None) - msg[ARG]['_krpc_sender'] = self.addr - if f and callable(f): - try: - ret = f(*(), **msg[ARG]) - except Exception, e: - olen = self._sendResponse(addr, msg[TID], ERR, `format_exception(type(e), e, sys.exc_info()[2])`) - else: - olen = self._sendResponse(addr, msg[TID], RSP, ret) - else: - if self.noisy: - log.msg("don't know about method %s" % msg[REQ]) - # unknown method - olen = self._sendResponse(addr, msg[TID], ERR, KRPC_ERROR_METHOD_UNKNOWN) - if self.noisy: - log.msg("%s >>> %s - %s %s %s" % (addr, self.factory.node.port, - ilen, msg[REQ], olen)) - elif msg[TYP] == RSP: - # if response - # lookup tid - if self.tids.has_key(msg[TID]): - df = self.tids[msg[TID]] - # callback - del(self.tids[msg[TID]]) - df.callback({'rsp' : msg[RSP], '_krpc_sender': addr}) - else: - # no tid, this transaction timed out already... - if self.noisy: - log.msg('timeout: %r' % msg[RSP]['id']) - elif msg[TYP] == ERR: - # if error - # lookup tid - if self.tids.has_key(msg[TID]): - df = self.tids[msg[TID]] - # callback - df.errback(msg[ERR]) - del(self.tids[msg[TID]]) + return + + try: + verifyMessage(msg) + except Exception, e: + log.msg("krpc message verification error: ") + log.err(e) + return + + if self.noisy: + log.msg("%d received from %r: %s" % (self.factory.port, addr, msg)) + # look at msg type + if msg[TYP] == REQ: + ilen = len(data) + # if request + # tell factory to handle + f = getattr(self.factory ,"krpc_" + msg[REQ], None) + msg[ARG]['_krpc_sender'] = self.addr + if f and callable(f): + try: + ret = f(*(), **msg[ARG]) + except KrpcError, e: + log.msg('Got a Krpc error while running: krpc_%s' % msg[REQ]) + log.err(e) + olen = self._sendResponse(addr, msg[TID], ERR, [e[0], e[1]]) + except TypeError, e: + log.msg('Got a malformed request for: krpc_%s' % msg[REQ]) + log.err(e) + olen = self._sendResponse(addr, msg[TID], ERR, + [KRPC_ERROR_MALFORMED_REQUEST, str(e)]) + except Exception, e: + log.msg('Got an unknown error while running: krpc_%s' % msg[REQ]) + log.err(e) + olen = self._sendResponse(addr, msg[TID], ERR, + [KRPC_ERROR_SERVER_ERROR, str(e)]) else: - # day late and dollar short - pass + olen = self._sendResponse(addr, msg[TID], RSP, ret) else: - if self.noisy: - log.msg("unknown message type: %r" % msg) - # unknown message type + # unknown method + log.msg("ERROR: don't know about method %s" % msg[REQ]) + olen = self._sendResponse(addr, msg[TID], ERR, + [KRPC_ERROR_METHOD_UNKNOWN, "unknown method "+str(msg[REQ])]) + if self.noisy: + log.msg("%s >>> %s - %s %s %s" % (addr, self.factory.node.port, + ilen, msg[REQ], olen)) + elif msg[TYP] == RSP: + # if response + # lookup tid + if self.tids.has_key(msg[TID]): df = self.tids[msg[TID]] # callback - df.errback(KRPC_ERROR_RECEIVED_UNKNOWN) del(self.tids[msg[TID]]) + df.callback({'rsp' : msg[RSP], '_krpc_sender': addr}) + else: + # no tid, this transaction timed out already... + if self.noisy: + log.msg('timeout: %r' % msg[RSP]['id']) + elif msg[TYP] == ERR: + # if error + # lookup tid + if self.tids.has_key(msg[TID]): + df = self.tids[msg[TID]] + del(self.tids[msg[TID]]) + # callback + df.errback(KrpcError(*msg[ERR])) + else: + # day late and dollar short, just log it + log.msg("Got an error for an unknown request: %r" % (msg[ERR], )) + pass + else: + if self.noisy: + log.msg("unknown message type: %r" % msg) + # unknown message type + if msg[TID] in self.tids: + df = self.tids[msg[TID]] + del(self.tids[msg[TID]]) + # callback + df.errback(KrpcError(KRPC_ERROR_RECEIVED_UNKNOWN, + "Received an unknown message type: %r" % msg[TYP])) def _sendResponse(self, addr, tid, msgType, response): if not response: response = {} + + try: + msg = {TID : tid, TYP : msgType, msgType : response} + + if self.noisy: + log.msg("%d responding to %r: %s" % (self.factory.port, addr, msg)) + + out = bencode(msg) - msg = {TID : tid, TYP : msgType, msgType : response} - - if self.noisy: - log.msg("%d responding to %r: %s" % (self.factory.port, addr, msg)) + if len(out) > UDP_PACKET_LIMIT: + if 'values' in response: + # Save the original list of values + orig_values = response['values'] + len_orig_values = len(bencode(orig_values)) + + # Caclulate the maximum value length possible + max_len_values = len_orig_values - (len(out) - UDP_PACKET_LIMIT) + assert max_len_values > 0 + + # Start with a calculation of how many values should be included + # (assumes all values are the same length) + per_value = (float(len_orig_values) - 2.0) / float(len(orig_values)) + num_values = len(orig_values) - int(ceil(float(len(out) - UDP_PACKET_LIMIT) / per_value)) + + # Do a linear search for the actual maximum number possible + bencoded_values = len(bencode(orig_values[:num_values])) + while bencoded_values < max_len_values and num_values + 1 < len(orig_values): + bencoded_values += len(bencode(orig_values[num_values])) + num_values += 1 + while bencoded_values > max_len_values and num_values > 0: + num_values -= 1 + bencoded_values -= len(bencode(orig_values[num_values])) + assert num_values > 0 + + # Encode the result + response['values'] = orig_values[:num_values] + out = bencode(msg) + assert len(out) < UDP_PACKET_LIMIT + log.msg('Shortened a long packet from %d to %d values, new packet length: %d' % + (len(orig_values), num_values, len(out))) + else: + # Too long a response, send an error + log.msg('Could not send response, too long: %d bytes' % len(out)) + msg = {TID : tid, TYP : ERR, ERR : [KRPC_ERROR_RESPONSE_TOO_LONG, "response was %d bytes" % len(out)]} + out = bencode(msg) - out = bencode(msg) + except Exception, e: + # Unknown error, send an error message + msg = {TID : tid, TYP : ERR, ERR : [KRPC_ERROR_SERVER_ERROR, "unknown error sending response: %s" % str(e)]} + out = bencode(msg) + self.transport.write(out, addr) return len(out) def sendRequest(self, method, args): if self.stopped: - raise ProtocolError, "connection has been stopped" + raise KrpcError, (KRPC_ERROR_PROTOCOL_STOPPED, "cannot send, connection has been stopped") # make message # send it msg = {TID : newID(), TYP : REQ, REQ : method, ARG : args} if self.noisy: log.msg("%d sending to %r: %s" % (self.factory.port, self.addr, msg)) - str = bencode(msg) + data = bencode(msg) d = Deferred() self.tids[msg[TID]] = d - def timeOut(tids = self.tids, id = msg[TID], msg = msg): + def timeOut(tids = self.tids, id = msg[TID], method = method, addr = self.addr): if tids.has_key(id): df = tids[id] del(tids[id]) - log.msg(">>>>>> KRPC_ERROR_TIMEOUT") - df.errback(ProtocolError('timeout waiting for %r' % msg)) + df.errback(KrpcError(KRPC_ERROR_TIMEOUT, "timeout waiting for '%s' from %r" % (method, addr))) later = reactor.callLater(KRPC_TIMEOUT, timeOut) def dropTimeOut(dict, later_call = later): if later_call.active(): later_call.cancel() return dict d.addBoth(dropTimeOut) - self.transport.write(str, self.addr) + self.transport.write(data, self.addr) return d def stop(self): """Timeout all pending requests.""" for df in self.tids.values(): - df.errback(ProtocolError('connection has been closed')) + df.errback(KrpcError(KRPC_ERROR_PROTOCOL_STOPPED, 'connection has been stopped while waiting for response')) self.tids = {} self.stopped = True @@ -199,8 +319,11 @@ class Receiver(protocol.Factory): self.buf = [] def krpc_store(self, msg, _krpc_sender): self.buf += [msg] + return {} def krpc_echo(self, msg, _krpc_sender): - return msg + return {'msg': msg} + def krpc_values(self, length, num, _krpc_sender): + return {'values': ['1'*length]*num} def make(port): af = Receiver() @@ -210,6 +333,8 @@ def make(port): return af, a, p class KRPCTests(unittest.TestCase): + timeout = 2 + def setUp(self): self.af, self.a, self.ap = make(1180) self.bf, self.b, self.bp = make(1181) @@ -240,7 +365,7 @@ class KRPCTests(unittest.TestCase): def gotMsg(self, dict, should_be): _krpc_sender = dict['_krpc_sender'] msg = dict['rsp'] - self.failUnlessEqual(msg, should_be) + self.failUnlessEqual(msg['msg'], should_be) def testManyEcho(self): for i in xrange(100): @@ -277,8 +402,24 @@ class KRPCTests(unittest.TestCase): def testUnknownMeth(self): df = self.a.connectionForAddr(('127.0.0.1', 1181)).sendRequest('blahblah', {'msg' : "This is a test."}) - df.addErrback(self.gotErr, KRPC_ERROR_METHOD_UNKNOWN) + df.addBoth(self.gotErr, KRPC_ERROR_METHOD_UNKNOWN) + return df + + def testMalformedRequest(self): + df = self.a.connectionForAddr(('127.0.0.1', 1181)).sendRequest('echo', {'msg' : "This is a test.", 'foo': 'bar'}) + df.addBoth(self.gotErr, KRPC_ERROR_MALFORMED_REQUEST) return df def gotErr(self, err, should_be): - self.failUnlessEqual(err.value, should_be) + self.failUnlessEqual(err.value[0], should_be) + + def testLongPackets(self): + df = self.a.connectionForAddr(('127.0.0.1', 1181)).sendRequest('values', {'length' : 1, 'num': 2000}) + df.addCallback(self.gotLongRsp) + return df + + def gotLongRsp(self, dict): + # Not quite accurate, but good enough + self.failUnless(len(bencode(dict))-10 < UDP_PACKET_LIMIT) + + \ No newline at end of file