""" ngircd.py: PyLink protocol module for ngIRCd. """ ## # Server protocol docs for ngIRCd can be found at: # https://github.com/ngircd/ngircd/blob/master/doc/Protocol.txt # and https://tools.ietf.org/html/rfc2813 ## import re import time from pylinkirc import __version__, conf, utils from pylinkirc.classes import * from pylinkirc.log import log from pylinkirc.protocols.ircs2s_common import * class NgIRCdProtocol(IRCS2SProtocol): def __init__(self, irc): super().__init__(irc) self.conf_keys -= {'sid', 'sidrange'} self.casemapping = 'ascii' # This is the default; it's actually set on server negotiation self.hook_map = {'NJOIN': 'JOIN'} # Track whether we've received end-of-burst from the uplink. self.has_eob = False self._caps = {} self._use_builtin_005_handling = True # ngIRCd has no TS tracking. self.protocol_caps.discard('has-ts') # Slash in nicks is problematic; while it works for basic things like JOIN and messages, # attempts to set user modes fail. self.protocol_caps |= {'slash-in-hosts', 'underscore-in-hosts'} ### Commands def post_connect(self): self.send('PASS %s 0210-IRC+ PyLink|%s:CHLMoX' % (self.serverdata['sendpass'], __version__)) # Note: RFC 2813 mandates another server token value after the hopcount (1), but ngIRCd # doesn't follow that behaviour per https://github.com/ngircd/ngircd/issues/224 self.send("SERVER %s 1 :%s" % (self.serverdata['hostname'], self.serverdata.get('serverdesc') or conf.conf['pylink']['serverdesc'])) self._uidgen = PUIDGenerator('PUID') # The first "SID" this generator should return is 2, because server token 1 is implied to be # the main PyLink server. RFC2813 has no official definition of SIDs, but rather uses # integer tokens in the SERVER and NICK (user introduction) commands to keep track of which # user exists on which server. Why did they do it this way? Who knows! self._sidgen = PUIDGenerator('PSID', start=1) self.sid = self._sidgen.next_sid(prefix=self.serverdata['hostname']) self._caps.clear() self.cmodes.update({ 'banexception': 'e', 'invex': 'I', 'noinvite': 'V', 'nokick': 'Q', 'nonick': 'N', 'operonly': 'O', 'permanent': 'P', 'registered': 'r', 'regmoderated': 'M', 'regonly': 'R', 'sslonly': 'z' }) self.umodes.update({ 'away': 'a', 'bot': 'B', 'cloak': 'x', 'deaf_commonchan': 'C', 'floodexempt': 'F', 'hidechans': 'I', 'privdeaf': 'b', 'registered': 'R', 'restricted': 'r', 'servprotect': 'q', 'sno_clientconnections': 'c' }) def spawn_client(self, nick, ident='null', host='null', realhost=None, modes=set(), server=None, ip='0.0.0.0', realname=None, ts=None, opertype='IRC Operator', manipulatable=False): """ Spawns a new client with the given options. Note: No nick collision / valid nickname checks are done here; it is up to plugins to make sure they don't introduce anything invalid. Note 2: IP and realhost are ignored because ngIRCd does not send them. """ server = server or self.sid assert '@' in server, "Need PSID for spawn_client, not pure server name!" if not self.is_internal_server(server): raise ValueError('Server %r is not a PyLink server!' % server) realname = realname or conf.conf['pylink']['realname'] uid = self._uidgen.next_uid(prefix=nick) userobj = self.users[uid] = User(self, nick, ts or int(time.time()), uid, server, ident=ident, host=host, realname=realname, manipulatable=manipulatable, opertype=opertype, realhost=host) self.apply_modes(uid, modes) self.servers[server].users.add(uid) # Grab our server token; this is used instead of server name to denote where the client is. server_token = server.rsplit('@')[-1] # <- :ngircd.midnight.local NICK GL 1 ~gl localhost 1 +io :realname self._send_with_prefix(server, 'NICK %s %s %s %s %s %s :%s' % (nick, self.servers[server].hopcount, ident, host, server_token, self.join_modes(modes), realname)) return userobj def spawn_server(self, name, sid=None, uplink=None, desc=None): """ Spawns a server off a PyLink server. * desc (server description) defaults to the one in the config. * uplink defaults to the main PyLink server. * SID is set equal to the server name for ngIRCd, as server UIDs are not used. """ uplink = uplink or self.sid assert uplink in self.servers, "Unknown uplink %r?" % uplink name = name.lower() sid = self._sidgen.next_sid(prefix=name) desc = desc or self.serverdata.get('serverdesc') or conf.conf['pylink']['serverdesc'] if sid in self.servers: raise ValueError('A server named %r already exists!' % sid) if not self.is_internal_server(uplink): raise ValueError('Server %r is not a PyLink server!' % uplink) if not self.is_server_name(name): raise ValueError('Invalid server name %r' % name) # https://tools.ietf.org/html/rfc2813#section-4.1.2 # We need to store a server token to introduce clients on the right server. Since this is just # a number, we can simply use the counter in our PSID generator for this. server_token = sid.rsplit('@')[-1] self.servers[sid] = Server(self, uplink, name, internal=True, desc=desc) self._send_with_prefix(uplink, 'SERVER %s %s %s :%s' % (name, self.servers[sid].hopcount, server_token, desc)) return sid def away(self, source, text): """Sends an AWAY message from a PyLink client. If the text is empty, away status is unset.""" if not self.is_internal_client(source): raise LookupError('No such PyLink client exists.') # Away status is denoted on ngIRCd with umode +a. modes = self.users[source].modes if text and (('a', None) not in modes): # Set umode +a if it isn't already set self.mode(source, source, [('+a', None)]) elif ('a', None) in modes: # Ditto, only unset the mode if it *was* set. self.mode(source, source, [('-a', None)]) self.users[source].away = text def join(self, client, channel): if not self.is_internal_client(client): raise LookupError('No such PyLink client exists.') self._send_with_prefix(client, "JOIN %s" % channel) self._channels[channel].users.add(client) self.users[client].channels.add(channel) def kill(self, source, target, reason): """Sends a kill from a PyLink client/server.""" if (not self.is_internal_client(source)) and \ (not self.is_internal_server(source)): raise LookupError('No such PyLink client/server exists.') # Follow ngIRCd's formatting of the kill messages for the most part self._send_with_prefix(source, 'KILL %s :KILLed by %s: %s' % (self._expandPUID(target), self.get_friendly_name(source), reason)) # Implicitly remove our own client if one was the target. if self.is_internal_client(target): self._remove_client(target) def knock(self, numeric, target, text): raise NotImplementedError('KNOCK is not supported on ngIRCd.') def mode(self, source, target, modes, ts=None): """Sends mode changes from a PyLink client/server. The TS option is not used on ngIRCd.""" if (not self.is_internal_client(source)) and \ (not self.is_internal_server(source)): raise LookupError('No such PyLink client/server %r exists' % source) self.apply_modes(target, modes) modes = list(modes) # Work around TypeError in the expand PUID section if self.is_channel(target): msgprefix = ':%s MODE %s ' % (self._expandPUID(source), target) bufsize = self.S2S_BUFSIZE - len(msgprefix) # Expand PUIDs when sending outgoing prefix modes. for idx, mode in enumerate(modes): if mode[0][-1] in self.prefixmodes: log.debug('(%s) mode: expanding PUID of mode %s', self.name, str(mode)) modes[idx] = (mode[0], self._expandPUID(mode[1])) for modestr in self.wrap_modes(modes, bufsize, max_modes_per_msg=12): self.send(msgprefix + modestr) else: joinedmodes = self.join_modes(modes) self._send_with_prefix(source, 'MODE %s %s' % (self._expandPUID(target), joinedmodes)) def nick(self, source, newnick): """Changes the nick of a PyLink client.""" if not self.is_internal_client(source): raise LookupError('No such PyLink client exists.') self._send_with_prefix(source, 'NICK %s' % newnick) self.users[source].nick = newnick # Update the nick TS for consistency with other protocols (it isn't actually used in S2S) self.users[source].ts = int(time.time()) def sjoin(self, server, channel, users, ts=None, modes=set()): """Sends an SJOIN for a group of users to a channel. The sender should always be a Server ID (SID). TS is optional, and defaults to the one we've stored in the channel state if not given. is a list of (prefix mode, UID) pairs: Example uses: sjoin('100', '#test', [('', 'user0@0'), ('o', user1@1'), ('v', 'someone@2')]) sjoin(self.sid, '#test', [('o', self.pseudoclient.uid)]) """ server = server or self.sid if not server: raise LookupError('No such PyLink client exists.') log.debug('(%s) sjoin: got %r for users', self.name, users) njoin_prefix = ':%s NJOIN %s :' % (self._expandPUID(server), channel) # Format the user list into strings such as @user1, +user2, user3, etc. nicks_to_send = [] for userpair in users: prefixes, uid = userpair if uid not in self.users: log.warning('(%s) Trying to NJOIN missing user %s?', self.name, uid) continue elif uid in self._channels[channel].users: # Don't rejoin users already in the channel, this causes errors with ngIRCd. continue self._channels[channel].users.add(uid) self.users[uid].channels.add(channel) self.apply_modes(channel, (('+%s' % prefix, uid) for prefix in userpair[0])) nicks_to_send.append(''.join(self.prefixmodes[modechar] for modechar in userpair[0]) + \ self._expandPUID(userpair[1])) if nicks_to_send: # Use 13 args max per line: this is equal to the max of 15 minus the command name and target channel. for message in utils.wrap_arguments(njoin_prefix, nicks_to_send, self.S2S_BUFSIZE, separator=',', max_args_per_line=13): self.send(message) if modes: # Burst modes separately if there are any. log.debug("(%s) sjoin: bursting modes %r for channel %r now", self.name, modes, channel) self.mode(server, channel, modes) def set_server_ban(self, source, duration, user='*', host='*', reason='User banned'): """ Sets a server ban. """ # <- :GL GLINE *!*@bad.user 3d :test assert not (user == host == '*'), "Refusing to set ridiculous ban on *@*" self._send_with_prefix(source, 'GLINE *!%s@%s %s :%s' % (user, host, duration, reason)) def update_client(self, target, field, text): """Updates the ident, host, or realname of any connected client.""" field = field.upper() if field not in ('IDENT', 'HOST', 'REALNAME', 'GECOS'): raise NotImplementedError("Changing field %r of a client is " "unsupported by this protocol." % field) real_target = self._expandPUID(target) if field == 'IDENT': self.users[target].ident = text self._send_with_prefix(self.sid, 'METADATA %s user :%s' % (real_target, text)) if not self.is_internal_client(target): # If the target wasn't one of our clients, send a hook payload for other plugins to listen to. self.call_hooks([self.sid, 'CHGIDENT', {'target': target, 'newident': text}]) elif field == 'HOST': self.users[target].host = text if self.is_internal_client(target): # For our own clients, replace the real host. self._send_with_prefix(self.sid, 'METADATA %s host :%s' % (real_target, text)) else: # For others, update the cloaked host and force a umode +x. self._send_with_prefix(self.sid, 'METADATA %s cloakhost :%s' % (real_target, text)) if ('x', None) not in self.users[target].modes: log.debug('(%s) Forcing umode +x on %r as part of cloak setting', self.name, target) self.mode(self.sid, target, [('+x', None)]) self.call_hooks([self.sid, 'CHGHOST', {'target': target, 'newhost': text}]) elif field in ('REALNAME', 'GECOS'): self.users[target].realname = text self._send_with_prefix(self.sid, 'METADATA %s info :%s' % (real_target, text)) if not self.is_internal_client(target): self.call_hooks([self.sid, 'CHGNAME', {'target': target, 'newgecos': text}]) ### Handlers def handle_376(self, source, command, args): # 376 is used to denote end of server negotiation - we send our info back at this point. # <- :ngircd.midnight.local 005 pylink-devel.int NETWORK=ngircd-test :is my network name # <- :ngircd.midnight.local 005 pylink-devel.int RFC2812 IRCD=ngIRCd CHARSET=UTF-8 CASEMAPPING=ascii PREFIX=(qaohv)~&@%+ CHANTYPES=#&+ CHANMODES=beI,k,l,imMnOPQRstVz CHANLIMIT=#&+:10 :are supported on this server # <- :ngircd.midnight.local 005 pylink-devel.int CHANNELLEN=50 NICKLEN=21 TOPICLEN=490 AWAYLEN=127 KICKLEN=400 MODES=5 MAXLIST=beI:50 EXCEPTS=e INVEX=I PENALTY :are supported on this server def f(numeric, msg): self._send_with_prefix(self.sid, '%s %s %s' % (numeric, self.uplink, msg)) f('005', 'NETWORK=%s :is my network name' % self.get_full_network_name()) f('005', 'RFC2812 IRCD=PyLink CHARSET=UTF-8 CASEMAPPING=%s PREFIX=%s CHANTYPES=# ' 'CHANMODES=%s,%s,%s,%s :are supported on this server' % (self.casemapping, self._caps['PREFIX'], self.cmodes['*A'], self.cmodes['*B'], self.cmodes['*C'], self.cmodes['*D'])) f('005', 'CHANNELLEN NICKLEN=%s EXCEPTS=E INVEX=I :are supported on this server' % self.maxnicklen) # 376 (end of MOTD) marks the end of extended server negotiation per # https://github.com/ngircd/ngircd/blob/master/doc/Protocol.txt#L103-L112 f('376', ":End of server negotiation, happy PyLink'ing!") def handle_chaninfo(self, source, command, args): # https://github.com/ngircd/ngircd/blob/722afc1b810cef74dbd2738d71866176fd974ec2/doc/Protocol.txt#L146-L159 # CHANINFO has 3 styles depending on the amount of information applicable to a channel: # CHANINFO + # CHANINFO + # CHANINFO + # If there is no key, the key is "*". If there is no limit, the limit is "0". channel = args[0] # Get rid of +l and +k in the initial parsing; we handle that later by looking at the CHANINFO arguments modes = self.parse_modes(channel, args[1].replace('l', '').replace('k', '')) if len(args) >= 3: topic = args[-1] if topic: log.debug('(%s) handle_chaninfo: setting topic for %s to %r', self.name, channel, topic) self._channels[channel].topic = topic self._channels[channel].topicset = True if len(args) >= 5: key = args[2] limit = args[3] if key != '*': modes.append(('+k', key)) if limit != '0': modes.append(('+l', limit)) self.apply_modes(channel, modes) def handle_join(self, source, command, args): # RFC 2813 is odd to say the least... https://tools.ietf.org/html/rfc2813#section-4.2.1 # Basically, we expect messages of the forms: # <- :GL JOIN #test\x07o # <- :GL JOIN #moretest for chanpair in args[0].split(','): # Normalize channel case. try: channel, status = chanpair.split('\x07', 1) if status in 'ov': self.apply_modes(channel, [('+' + status, source)]) except ValueError: channel = chanpair c = self._channels[channel] self.users[source].channels.add(channel) self._channels[channel].users.add(source) # Call hooks manually, because one JOIN command have multiple channels. self.call_hooks([source, command, {'channel': channel, 'users': [source], 'modes': c.modes}]) def handle_kill(self, source, command, args): """Handles incoming KILLs.""" # ngIRCd sends QUIT after KILL for its own clients, so we shouldn't process this by itself # unless we're the target. killed = self._get_UID(args[0]) if self.is_internal_client(killed): return super().handle_kill(source, command, args) else: log.debug("(%s) Ignoring KILL to %r as it isn't meant for us; we should see a QUIT soon", self.name, killed) def _check_cloak_change(self, target): u = self.users[target] old_host = u.host if ('x', None) in u.modes and u.cloaked_host: u.host = u.cloaked_host elif u.realhost: u.host = u.realhost # Something changed, so send a CHGHOST hook if old_host != u.host: self.call_hooks([target, 'CHGHOST', {'target': target, 'newhost': u.host}]) def handle_metadata(self, source, command, args): """Handles various user metadata for ngIRCd (cloaked host, account name, etc.)""" # <- :ngircd.midnight.local METADATA GL cloakhost :hidden-3a2a739e.ngircd.midnight.local target = self._get_UID(args[0]) if target not in self.users: log.warning("(%s) Ignoring METADATA to missing user %r?", self.name, target) return datatype = args[1] u = self.users[target] if datatype == 'cloakhost': # Set cloaked host u.cloaked_host = args[-1] self._check_cloak_change(target) elif datatype == 'host': # Host changing. This actually sets the "real host" that ngIRCd stores u.realhost = args[-1] self._check_cloak_change(target) elif datatype == 'user': # Ident changing u.ident = args[-1] self.call_hooks([target, 'CHGIDENT', {'target': target, 'newident': args[-1]}]) elif datatype == 'info': # Realname changing u.realname = args[-1] self.call_hooks([target, 'CHGNAME', {'target': target, 'newgecos': args[-1]}]) elif datatype == 'accountname': # Services account self.call_hooks([target, 'CLIENT_SERVICES_LOGIN', {'text': args[-1]}]) def handle_nick(self, source, command, args): """ Handles the NICK command, used for server introductions and nick changes. """ if len(args) >= 2: # User introduction: # <- :ngircd.midnight.local NICK GL 1 ~gl localhost 1 +io :realname nick = args[0] assert source in self.servers, "Server %r tried to introduce nick %r but isn't in the servers index?" % (source, nick) self._check_nick_collision(nick) ident = args[2] host = args[3] uid = self._uidgen.next_uid(prefix=nick) realname = args[-1] ts = int(time.time()) self.users[uid] = User(self, nick, ts, uid, source, ident=ident, host=host, realname=realname, realhost=host) parsedmodes = self.parse_modes(uid, [args[5]]) self.apply_modes(uid, parsedmodes) # Add the nick to the list of users on its server; this is used for SQUIT tracking self.servers[source].users.add(uid) # Check away status and cloaked host changes self._check_umode_away_change(uid) self._check_cloak_change(uid) return {'uid': uid, 'ts': ts, 'nick': nick, 'realhost': host, 'host': host, 'ident': ident, 'parse_as': 'UID', 'ip': '0.0.0.0'} else: # Nick changes: # <- :GL NICK :GL_ oldnick = self.users[source].nick newnick = self.users[source].nick = args[0] return {'newnick': newnick, 'oldnick': oldnick} def handle_njoin(self, source, command, args): # <- :ngircd.midnight.local NJOIN #test :tester,@%GL channel = args[0] chandata = self._channels[channel].deepcopy() namelist = [] # Reverse the modechar->modeprefix mapping for quicker lookup prefixchars = {v: k for k, v in self.prefixmodes.items()} for userpair in args[1].split(','): # Some regex magic to split the prefix from the nick. r = re.search(r'([%s]*)(.*)' % ''.join(self.prefixmodes.values()), userpair) user = self._get_UID(r.group(2)) modeprefix = r.group(1) if modeprefix: modes = {('+%s' % prefixchars[mode], user) for mode in modeprefix} self.apply_modes(channel, modes) namelist.append(user) # Final bits of state tracking. (I hate having to do this everywhere...) self.users[user].channels.add(channel) self._channels[channel].users.add(user) return {'channel': channel, 'users': namelist, 'modes': [], 'channeldata': chandata} def handle_pass(self, source, command, args): """ Handles phase one of the ngIRCd login process (password auth and version info). """ # PASS is step one of server introduction, and is used to send the server info and password. # <- :ngircd.midnight.local PASS xyzpassword 0210-IRC+ ngIRCd|24~3-gbc728f92:CHLMSXZ PZ recvpass = args[0] if recvpass != self.serverdata['recvpass']: raise ProtocolError("RECVPASS from uplink does not match configuration!") if 'IRC+' not in args[1]: raise ProtocolError("Linking to non-ngIRCd server using this protocol module is not supported") def handle_ping(self, source, command, args): """ Handles incoming PINGs (and implicit end of burst). """ self._send_with_prefix(self.sid, 'PONG %s :%s' % (self._expandPUID(self.sid), args[-1]), queue=False) if not self.servers[source].has_eob: # Treat the first PING we receive as end of burst. self.servers[source].has_eob = True if source == self.uplink: self.connected.set() # Return the endburst hook. return {'parse_as': 'ENDBURST'} def handle_server(self, source, command, args): """ Handles the SERVER command. """ # <- :ngircd.midnight.local SERVER ngircd.midnight.local 1 :ngIRCd dev server servername = args[0].lower() serverdesc = args[-1] # The uplink should be set to None for the uplink; otherwise, set it equal to the sender server. self.servers[servername] = Server(self, source if source != servername else None, servername, desc=serverdesc) if self.uplink is None: self.uplink = servername log.debug('(%s) Got %s as uplink', self.name, servername) else: # Only send the SERVER hook if this isn't the initial connection. return {'name': servername, 'sid': None, 'text': serverdesc} Class = NgIRCdProtocol