#!/usr/bin/env python3

# osmo-gsm-shark: produce a ladder diagram from and/or filter a GSM network pcap by subscriber.
# Copyright (C) 2019 by Neels Hofmeyr <neels@hofmeyr.de>
#
# All Rights Reserved
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

'''osmo-gsm-shark: produce a ladder diagram from and/or filter a GSM network pcap by subscriber.

Copyright (C) 2019 by Neels Hofmeyr <neels@hofmeyr.de>
SPDX-License-Identifier: GPL-2.0+

This tool uses tshark (pyshark) to analyze a pcap file or a live network capture to:

- Associate almost all messages with a subscriber. It is possible to filter by subscriber.
- Separate the different network elements (BSC, MSC, hNodeB, ...).
- Output a ladder diagram.
- Combine repetitive messages.
- Combine/abstract messages into short activity summary.

Examples:

	osmo-gsm-shark -f trace.pcapng
	osmo-gsm-shark -l any

	osmo-gsm-shark -l any --filter-subscr 901701234567123
	osmo-gsm-shark -f trace.pcapng --filter-msg dtap
'''

import collections
import pyshark
import re
import sys
import types
import time
import traceback

SHOW_ALL_DEBUG = False

SHOW_ALL_LAYERS = False
SCCP_COLLAPSE_STP = True
IUH_COLLAPSE_HNBGW = True # doesnt work

DTAP_COMPL_L3 = ('Location-Updating-Request', 'CM-Service-Request', 'Paging-Response', 'IMSI-Detach-Indication')
GMM_COMPL_L3 = ('Attach-Request', 'Detach-Request')

class Color:
	codes = (
		('red', '\033[1;31m'),
		('green', '\033[1;32m'),
		('yellow', '\033[1;33m'),
		('blue', '\033[1;34m'),
		('purple', '\033[1;35m'),
		('cyan', '\033[1;36m'),
		('darkred', '\033[31m'),
		('darkgreen', '\033[32m'),
		('darkyellow', '\033[33m'),
		('darkblue', '\033[34m'),
		('darkpurple', '\033[35m'),
		('darkcyan', '\033[36m'),
		('darkgrey', '\033[1;30m'),
		('brightwhite', '\033[1;37m'),
		)
	codes_dict = dict(codes)
	end = '\033[0;m'

	def colored(code, text):
		if type(code) is int:
			code = Color.codes[code % len(Color.codes)][1]
		else:
			code = Color.codes_dict[code]
		return f'{code}{text}{Color.end}'


def set_instance_vars_from_args(*ignore, self='s'):
	f = sys._getframe(1).f_locals
	s = f.get(self)
	for k,v in f.items():
		if v is s:
			continue
		if k in ignore:
			continue
		setattr(s, k, v)

def same_nonempty(a, b):
	if isinstance(a, types.GeneratorType):
		return list(a) == list(b)
	return a and a == b

def str_drop(a_str, drop_str):
	if a_str and a_str.startswith(drop_str):
		return a_str[len(drop_str):]
	return a_str

def sane_msgtype(msgtype):
	if not msgtype:
		return msgtype
	return sane_showname(msgtype).replace(' ','-')

re_msgtype_label = re.compile('message.type *', re.I)
def sane_showname(showname):
	if not showname:
		return showname
	if ': ' in showname:
		showname = showname[showname.index(': ')+1:]
	if '(' in showname:
		showname = showname[:showname.index('(')]
	showname = re_msgtype_label.sub('', showname)
	return showname.strip()

def dir_vals(elem):
	strs = []
	for name in dir(elem):
		if name.startswith('_'):
			continue
		try:
			strs.append('%r=%r' % (name, getattr(elem, name)))
		except:
			strs.append('%r=<Exception>' % (name))
	return '\n' + '\n'.join(strs)

def dir_p(p, name):
	return f'=== {name}\n{dir_vals(p.get(name))}\n---{name}'

def str_to_int(nr_str):
	'convert hex or decimal string to int'
	if not nr_str:
		return None
	elif nr_str.startswith('0x'):
		return int(nr_str, 16)
	else:
		return int(nr_str, 10)

def out_text(*args, **kwargs):
	print(*args, **kwargs)

g_ui = None
g_current_msg = None
g_debug_full = False

def to_text(*args, **kwargs):
	if kwargs:
		args = list(args) + [repr(kwargs)]
	return ' '.join(str(arg) for arg in args)

def out_text_now(*args, **kwargs):
	if g_ui is not None:
		g_ui.out_text_now(*args, **kwargs)
	else:
		print(to_text(*args, **kwargs))

def LOG(*args, **kwargs):
	if g_current_msg is not None:
		g_current_msg.log(*args, **kwargs)
	else:
		out_text_now(*args, **kwargs)

def DBG(*args, **kwargs):
	if g_current_msg is not None:
		g_current_msg.dbg(*args, **kwargs)
	else:
		out_text_now(*args, **kwargs)

def ERR(*args, **kwargs):
	LOG(Color.colored('red', '***** ERROR:'), *args, **kwargs)


def trace():
	return ''.join(traceback.format_stack())

def because_str(because):
	if not because:
		return '-'
	t = ['BECAUSE']
	for b in because:
		if isinstance(b, tuple) or isinstance(b, list):
			t.extend(because_str(b).splitlines())
		elif isinstance(b, str):
			t.append(b)
		elif isinstance(b, Message):
			t.append(b.str(show_traits=True, show_conns=True))
		else:
			t.append(str(b))
	return '\n|'.join(t)

def out_error(*args, **kwargs):
	if g_ui is not None:
		g_ui.out_error(*args, **kwargs)
	else:
		out_text_now(Color.colored('red', '*** ERROR:'), *args, **kwargs)
		if g_current_msg:
			out_text_now(Color.colored('red', '*** ERROR: while processing msg'), g_current_msg.str(show_traits=True, show_conns=True))
		out_text_now(trace())

def tmsi_standardize(tmsi):
	try:
		return format(int(tmsi), '08x')
	except:
		return None

# a dict containing a list for each key; l.add(name, item) adds item to the list at key=name.
class listdict(dict):
	'''A dict where each entry is a list of items'''
	def _have(ld, name):
		l = ld.get(name)
		if not l:
			l = []
			ld[name] = l
		return l

	def add(ld, name, item):
		l = ld._have(name)
		l.append(item)
		return ld

	def add_dict(ld, d):
		for k,v in d.items():
			ld.add(k, v)

	def update(ld, other_ld):
		for name, items in other_ld.items():
			ld.extend(name, items)
		return ld

	def extend(ld, name, vals):
		l = ld._have(name)
		l.extend(vals)
		return ld

	def remove(ld, name, item):
		l = ld.get(name)
		if item in l:
			l.remove(item)
	def _have(ld, name):
		l = ld.get(name)
		if not l:
			l = []
			ld[name] = l
		return l

	def add(ld, name, item):
		l = ld._have(name)
		l.append(item)
		return ld

	def add_dict(ld, d):
		for k,v in d.items():
			ld.add(k, v)

	def update(ld, other_ld):
		for name, items in other_ld.items():
			ld.extend(name, items)
		return ld

	def extend(ld, name, vals):
		l = ld._have(name)
		l.extend(vals)
		return ld

	def remove(ld, name, item):
		l = ld.get(name)
		if item in l:
			l.remove(item)

class UniqueList(list):
	def append(s, item):
		if item in s or item is None:
			return False
		super().append(item)
		return True

	def insert(s, idx, item):
		if item in s or item is None:
			return False
		super().insert(idx, item)
		return True

	def extend(s, items):
		added = 0
		for item in items:
			if s.append(item):
				added += 1
		return added

class NamedIds(dict):
	def __init__(s, start_id:int=1):
		set_instance_vars_from_args()

	def next(s, name):
		next_id = s.get(name, s.start_id)
		s[name] = next_id + 1
		return next_id

class Packet:
	def __init__(s, idx, cap_p):
		set_instance_vars_from_args()
		# sanitize impossible attr with dot in its name,
		# seen gsm_a.bssmap and gsm_a.dtap
		for name in dir(s.cap_p):
			if '.' in name:
				new_name = name.replace('.', '_')
			elif not name:
				new_name = 'unnamed'
			else:
				continue
			setattr(s.cap_p, new_name, getattr(s.cap_p, name))

	@classmethod
	def pget(cls, cap_p, tokens, ifnone=None):
		if cap_p is None or len(tokens) < 1:
			return ifnone
		p_field = getattr(cap_p, tokens[0], None)
		if p_field is None:
			p_field = getattr(cap_p, '.'.join(tokens), None)
		if p_field is None:
			return ifnone
		if len(tokens) > 1:
			return Packet.pget(p_field, tokens[1:], ifnone=ifnone)
		return p_field

	def get(s, field, ifnone=None):
		return Packet.pget(s.cap_p, field.split('.'), ifnone=ifnone)

	def str(s, elem_name=None):
		strs = []
		if elem_name:
			elem = s.get(elem_name)
		else:
			elem = s.cap_p
		return dir_vals(elem);

	def field_names(s, elem_name=None, elem=None):
		strs = ['', f'=== {elem_name} ===']
		if elem is None:
			elem = s.get(elem_name)
		if not elem:
			strs.append('None')
		else:
			for f in elem._get_all_fields_with_alternates():
				for n in dir(f):
					if n.startswith('_'):
						continue
					strs.append('%r=%r' % (n, getattr(f, n)))
		return '\n'.join(strs)

	def all_str(s, elem_name=None, elem=None, depth=1000):
		strs = []
		if elem is None:
			if elem_name:
				elem = s.get(elem_name)
			else:
				elem = s.cap_p
				elem_name = '/'
		strs.append('%s:' % elem_name)
		for name in dir(elem):
			if name.startswith('_') or name.endswith('_value') or name in [
					'sort', 'reverse', 'remove', 'pop', 'insert', 'index', 'extend', 'count',
					'copy', 'clear', 'append', 'zfill', 'max', 'min', 'resolution',
					]:
				continue
			try:
				full_name = '%s.%s' % (elem_name, name)
				val = getattr(elem, name)
				if callable(val) or name in ['base16_value']:
					continue
				strs.append('%r=%r' % (full_name, val))
				if depth and type(val) not in [int, str]:
					strs.append(s.all_str(full_name, val, depth-1))
			except:
				pass
		if hasattr(elem, '_get_all_fields_with_alternates'):
			for f in elem._get_all_fields_with_alternates():
				for n in dir(f):
					if n.startswith('_'):
						continue
					full_name = '%r[%r]' % (elem_name, n)
					try:
						val = getattr(f, n)
					except:
						continue
					if callable(val):
						continue
					strs.append('%s=%r' % (full_name, val))
					if depth:
						strs.append(s.all_str(full_name, val, depth-1))
		return '\n'.join(strs)

class IpPort:
	all_ports = {}

	@classmethod
	def _key(cls, ip, port):
		return f'{ip}:{port}'

	@classmethod
	def get(cls, ip, port, entity=None, proto=None, create=True):
		o = IpPort.all_ports.get(IpPort._key(ip, port))
		if o is None and create:
			return IpPort(ip, port, entity, proto)
		if o is not None:
			if entity is not None:
				if o.entity is not None and o.entity is not entity:
					ERR('Port changes:', o, 'to', entity)
					entity.add_port(o.proto, o)
		return o

	def __init__(s, ip:str=None, port:str=None, entity=None, proto=None):
		set_instance_vars_from_args()
		IpPort.all_ports[s.key()] = s

	def __repr__(s):
		r = ''
		tokens = []
		if s.entity:
			tokens.append(f'{s.entity}')
		if s.proto:
			tokens.append(f'{s.proto}')
		tokens.append(s.key())
		return '-'.join(tokens)

	def __eq__(s, other):
		return s is other

	def __hash__(s):
		return hash(s.key())

	def key(s):
		return IpPort._key(s.ip, s.port)

	@classmethod
	def from_sdp(p:Packet):
		ip = p.get('sdp.connection_info_address')
		port = p.get('sdp.media_port')
		return IpPort.get(ip, port)

	@classmethod
	def _from_ip(cls, p:Packet, src_dst:str, port:int):
		ip = p.get('ip.' + src_dst)
		if ip is None:
			ipv6 = p.get('ipv6.' + src_dst)
			if ipv6 is not None:
				ip = '[' + ipv6 + ']'
		return IpPort.get(ip, port)

	@classmethod
	def from_ip_source(cls, p:Packet, port:int):
		return cls._from_ip(p, 'src', port)

	@classmethod
	def from_ip_dest(cls, p:Packet, port:int):
		return cls._from_ip(p, 'dst', port)

	@classmethod
	def from_udp_source(cls, p:Packet):
		return cls.from_ip_source(p, p.get('udp.srcport'))

	@classmethod
	def from_udp_dest(cls, p:Packet):
		return cls.from_ip_dest(p, p.get('udp.dstport'))

	@classmethod
	def from_tcp_source(cls, p:Packet):
		return cls.from_ip_source(p, p.get('tcp.srcport'))

	@classmethod
	def from_tcp_dest(cls, p:Packet):
		return cls.from_ip_dest(p, p.get('tcp.dstport'))

	@classmethod
	def from_sctp_source(cls, p:Packet):
		return cls.from_ip_source(p, p.get('sctp.srcport'))

	@classmethod
	def from_sctp_dest(cls, p:Packet):
		return cls.from_ip_dest(p, p.get('sctp.dstport'))

class Message:
	pass

class Trait:
	def __init__(s, **kwargs):
		if len(kwargs) > 1:
			raise Exception('only one trait allowed per Trait(): %r' % kwargs)
		for k, v in kwargs.items():
			s.name = k
			s.val = v

	def __repr__(s):
		return '%r=%r' % (s.name, s.val)

class Traits(collections.OrderedDict):
	def __init__(s, *args, **kwargs):
		for arg in args:
			s.add(arg)
		s.set_vals(**kwargs)

	def add(s, trait:Trait):
		s[trait.name] = trait

	def set(s, name, val):
		if val is not None:
			s.add(Trait(**{name: val}))

	def set_vals(s, **kwargs):
		for k,v in kwargs.items():
			if v is None:
				continue
			if type(v) not in (str, int, float, bool, IpPort):
				v = str(v)
			s.set(k, v)

	def __repr__(s):
		strs = []
		for k,trait in s.items():
			assert k == trait.name
			strs.append(repr(trait))
		return '{%s}' % ', '.join(strs)

def find_recent_msg(msg:Message, messages:list, my_idx:int, condition_func, max_t=1):
	for i in reversed(range(my_idx)):
		prev_msg = messages[i]
		if not prev_msg:
			continue
		if prev_msg.finalized:
			return None
		if msg.timestamp - prev_msg.timestamp > max_t:
			return None
		if condition_func(prev_msg):
			yield prev_msg
	return None

def find_same_trait(msg:Message, messages:list, my_idx:int, proto:str, name:str, max_t=1, operator=any):
	def same_traits(prev_msg):
		return msg.same_traits(prev_msg, proto, name, operator=operator)
	return find_recent_msg(msg, messages, my_idx, same_traits, max_t)

class dddict(dict):
	@classmethod
	def _get(cls, d, keys, create=False):
		if not keys:
			return d
		k = keys[0]
		v = d.get(k)
		if len(keys) > 0:
			if v is None:
				if create:
					v = {}
					d[k] = v
				else:
					return None
		r = cls._get(v, keys[1:], create=create)
		return r

	def gget(s, keys, create=None):
		v = dddict._get(s, keys, create=False)
		if v is None:
			if create is None:
				return None
			else:
				return s.sset(keys, create)
		return v

	def sset(s, keys, item):
		d = dddict._get(s, keys[:-1], create=True)
		d[keys[-1]] = item
		return item

	def ppop(s, keys):
		d = dddict._get(s, keys[:-1])
		if d is None:
			return None
		r = d.pop(keys[-1])
		if not d:
			if len(keys) > 1:
				s.ppop(keys[:-1])
		return r

	@classmethod
	def _count(cls, d):
		if isinstance(d, dict):
			count = 0
			for val in d.values():
				count += cls._count(val)
			return count
		return 1

	def count(s):
		return dddict._count(s)

	@classmethod
	def _all(cls, d):
		if isinstance(d, dict):
			for val in d.values():
				yield from cls._all(val)
		else:
			yield d

	def all(s):
		return dddict._all(s)


class Conn:
	open_conns = dddict()
	closed_conns = dddict()

	'''One end of a time-limited connection for a protocol layer'''
	def __init__(s, proto:str, port:IpPort, conn_id:str, start_msg:Message, close_msg:Message=None, idx=-1,
		     entity=None, counterparts:list=[], subscriber_conn=None, merge_counterparts=True, add_message=True,
		     meta=False):
		set_instance_vars_from_args('entity', 'add_message', 'merge_counterparts')
		s.tx_messages = UniqueList()
		s.rx_messages = UniqueList()
		if s.subscriber_conn:
			s.subscriber_conn.conns.append(s)

		s.keys = (proto, port.key(), conn_id)
		Conn.open_conns.sset(s.keys, s)
		# A counterpart is the same conn seen from the other side.
		# For example, if a BSC opens a conn, the conterpart is the MSC's perspective on the same conn.
		s.counterparts = UniqueList()
		for cp in counterparts:
			if cp is None:
				continue
			s.counterparts.append(cp)
			cp.counterparts.append(s)

		if entity:
			entity.add_port(proto, port, from_msg=start_msg)

		if add_message:
			s.add_message(start_msg)

		if not counterparts:
			LOG(Color.colored('green', f'New conn (now {Conn.count_open_conns()})'), s.proto, '%r' % s.conn_id)
		if merge_counterparts:
			for other_conn in s.counterparts:
				s.merge_subscr_conns(other_conn)

	@classmethod
	def _find(cls, keys, find_in_closed_conns=False):
		ret = Conn.open_conns.gget(keys)
		if ret is not None:
			return ret
		if find_in_closed_conns:
			return Conn.closed_conns.gget(keys)
		return None

	@classmethod
	def find(cls, proto:str, port:IpPort, conn_id:str, find_in_closed_conns=False):
		return cls._find((proto, port.key(), conn_id), find_in_closed_conns=find_in_closed_conns)

	@classmethod
	def open(cls, proto:str, port:IpPort, conn_id:str, *args, **kwargs):
		exists = cls.find(proto, port, conn_id)
		if exists is not None:
			ERR('Conn already open:', type(exists), repr(exists))
			LOG(trace())
		return Conn(proto, port, conn_id, *args, **kwargs)

	@classmethod
	def find_or_open(cls, proto:str, port:IpPort, conn_id:str, *args, **kwargs):
		exists = cls.find(proto, port, conn_id)
		if exists is not None:
			return exists
		return Conn(proto, port, conn_id, *args, **kwargs)

	@classmethod
	def open_2way(cls, proto:str, conn_id:str, msg:Message, *args, **kwargs):
		conn1 = cls.open(proto, msg.src, conn_id, msg, *args, **kwargs)
		cls.open(proto, msg.dst, conn_id, msg, *args, counterparts=[conn1], **kwargs)
		return conn1

	@classmethod
	def close_conn(cls, conn, msg):
		conn._add_message(msg)
		conn.close_msg = msg
		Conn.open_conns.ppop(conn.keys)
		l = Conn.closed_conns.gget(conn.keys, create=[])
		l.append(conn)
		LOG(Color.colored('blue', f'Close conn ({Conn.count_open_conns()} left)'), conn)

	@classmethod
	def close(cls, proto, port, conn_id, close_msg, close_counterparts=True, if_exists=False):
		conn = Conn.find(proto, port, conn_id)
		if conn is None or not conn.is_open():
			if if_exists == False:
				ERR('Cannot close, conn not open:', Conn.key_label(proto, port, conn_id))
			return None
		Conn.close_conn(conn, close_msg)
		assert Conn.find(proto, port, conn_id) is None
		if close_counterparts:
			for cp in conn.counterparts:
				if cp.is_open():
					Conn.close_conn(cp, close_msg)
		return conn

	@classmethod
	def message(cls, proto, port, conn_id, msg):
		conn = cls.find(proto, port, conn_id)
		if conn is None:
			return None
		conn.add_message(msg)
		return conn

	def _add_message(s, msg):
		if s.port == msg.src:
			if s.meta:
				msg.meta_conns.append(s)
			else:
				msg.src_conns.append(s)
			s.tx_messages.append(msg)
		elif s.port == msg.dst:
			if s.meta:
				msg.meta_conns.append(s)
			else:
				msg.dst_conns.append(s)
			s.rx_messages.append(msg)

	def add_message(s, msg, add_to_counterparts=True):
		if s.close_msg:
			out_error('Message on a closed conn', s, msg)
		s._add_message(msg)
		if add_to_counterparts:
			for cp in s.counterparts:
				cp._add_message(msg)

	@classmethod
	def key_label(cls, proto, port, conn_id):
		if conn_id:
			return f'{proto}:{conn_id}@{port}'
		else:
			return f'{proto}@{port}'

	def label(s):
		return s.key_label(s.proto, s.port, s.conn_id)

	def __repr__(s):
		tokens = [s.label()]
		for r in s.counterparts:
			if r is None:
				tokens.append('None')
			else:
				tokens.append(r.label())
		return ' -> '.join(tokens)

	def merge_subscr_conns(s, other_conn):
		if other_conn is None:
			return
		if not isinstance(other_conn, Conn):
			for item in other_conn:
				s.merge_subscr_conns(item)
			return
		assert isinstance(other_conn, Conn)
		if s.subscriber_conn is not None and s.subscriber_conn is other_conn.subscriber_conn:
			return
		s.subscriber_conn = SubscriberConn.merge(s.subscriber_conn, other_conn.subscriber_conn)
		if s.subscriber_conn is None:
			s.subscriber_conn = SubscriberConn()
		s.subscriber_conn.add_conn(s)
		other_conn.subscriber_conn = s.subscriber_conn
		s.subscriber_conn.add_conn(other_conn)

	def find_entity(s, kind, with_port=None):
		if s.subscriber_conn:
			return s.subscriber_conn.find_entity(kind, with_port=with_port)
		return None, None

	def is_open(s):
		return s.close_msg is None and Conn._find(s.keys) is s

	@classmethod
	def count_open_conns(cls):
		count = 0
		have = set()
		for conn in cls.open_conns.all():
			do_count = True
			for conn2 in conn.counterparts:
				if conn2.label() in have:
					do_count = False
				have.add(conn2.label())
			if conn.label() in have:
				do_count = False
			have.add(conn.label())
			if do_count:
				count += 1
		return count


class Layer:

	_classes = {}
	traits = None
	proto = None
	cap_p_name = None

	def __init__(s, msg:Message, proto:str, msgtype:str, traits:Traits, minor=False, hidden=False, cap_p_name:str=None):
		set_instance_vars_from_args()
		if proto in msg.layers:
			raise Exception(f'duplicate proto {proto} for message')
		msg.layers[proto] = s
		s.msgtype = sane_msgtype(s.msgtype)
		if not s.cap_p_name:
			s.cap_p_name = s.proto
		s.__class__.proto = s.proto
		s.__class__.cap_p_name = s.cap_p_name

	def label(s):
		if s.msgtype:
			return f'{s.proto}.{s.msgtype}'
		else:
			return s.proto

	def identify_entities(s, msg:Message, messages, my_idx):
		'''return a list of Message.EntityIdent instances describing source and/or destination entity that message msg identifies.'''
		return None

	@classmethod
	def identify_conns(s, messages, my_idx):
		pass

	def collapse(s, messages, my_idx):
		'''return the message itself if it remains in messages, if another absorbed it return the other message,
		or if if it is dropped completely return None'''
		return messages[my_idx]

	@classmethod
	def classes(cls):
		if not Layer._classes:
			for cls in Layer.__subclasses__():
				name = cls.__name__
				if not name.startswith('Layer_'):
					continue
				proto_name = name[len('Layer_'):]
				Layer._classes[proto_name] = cls
				#cls.proto = proto_name
		return Layer._classes

	@classmethod
	def parse(cls, msg:Message):

		for proto_name,child_class in Layer.classes().items():
			if not msg.p.get(proto_name):
				continue
			child_class(msg)


class Message:

	def __init__(s, p:Packet, finalized=False):
		set_instance_vars_from_args()
		s.layers = collections.OrderedDict()
		s.count = 1
		s.count_back = 0
		s.timestamp = float(p.cap_p.sniff_timestamp)
		s.hide = False
		s.src = None
		s.dst = None
		s.src_conns = []
		s.dst_conns = []
		s.meta_conns = []
		s.absorbed = UniqueList()
		s.strong_relation = True
		s.debug = SHOW_ALL_DEBUG
		s._log = []

	def log(s, *text, **kwtext):
		s._log.append(to_text(*text, *kwtext))

	def dbg(s, *text, **kwtext):
		if s.debug:
			s._log.append(to_text(*text, *kwtext))

	def is_minor(s):
		return all(l.minor for l in s.layers.values())

	def get_trait(s, proto:str, name:str, ifnone=None):
		# allow alternative lists for proto, like s.get_trait(('tcp', 'udp'), 'src')
		if proto is None:
			proto = s.layers.keys()
		if type(proto) is not str:
			for proto_ in proto:
				val = s.get_trait(proto_, name, None)
				if val is not None:
					return val
			return ifnone
		# allow alternative lists for name, like s.get_trait('tcp', ('src', 'dst))
		if type(name) is not str:
			for name_ in name:
				val = s.get_trait(proto, name_, None)
				if val is not None:
					return val
			return ifnone

		if name == 'timestamp':
			return int(s.timestamp)
		layer = s.layers.get(proto, None)
		if not layer:
			return ifnone
		if name == 'msgtype':
			return layer.msgtype
		trait = layer.traits.get(name, None)
		if trait is None:
			return ifnone
		if trait.val is None:
			return ifnone
		return trait.val

	def get_traits(s, proto=None, names=None, proto_and_names=None):
		pn = []
		if proto or names:
			if proto is None or isinstance(proto, str):
				proto = [proto]
			for p in proto:
				pn.append((p, names))
		if proto_and_names:
			pn.extend(proto_and_names)
		for proto_, names in pn:
			if proto_ is None:
				proto_ = s.layers.keys()
			if isinstance(proto_, str):
				proto_ = [proto_]
			for proto in proto_:
				if names is None:
					l = s.layers.get(proto, None)
					if not l:
						continue
					names = l.traits.keys()
				if type(names) is str:
					names = [names]
				for name in names:
					result = s.get_trait(proto, name, ifnone=None)
					if result is not None:
						yield (proto, name, result)

	def get_all_traits(s, proto:str):
		layer = s.layers.get(proto)
		if not layer:
			return {}
		return layer.traits

	def same_traits(s, other_msg, proto:str, name:str, allow_unset=False, operator=all):
		if type(proto) is not str:
			return operator(
				s.same_traits(other_msg, proto_, name, allow_unset=allow_unset)
				for proto_ in proto
				)

		if name is None:
			my_traits = s.get_all_traits(proto)
			other_traits = other_msg.get_all_traits(proto)
			names = set(my_traits.keys())
			names.update(other_traits.keys())
			name = list(names)

		if type(name) is not str:
			return operator(
				s.same_traits(other_msg, proto, name_, allow_unset=allow_unset)
				for name_ in name
				)

		val = s.get_trait(proto, name)
		other_val = other_msg.get_trait(proto, name)
		if not allow_unset:
			if val is None or other_val is None:
				return False
		return val == other_val

	def set_trait(s, proto, name, val):
		layer = s.layers.get(proto, None)
		if layer is None:
			layer = Layer(s, proto, None, Traits(Trait(name, val)))
		else:
			layer.traits.set(name, val)

	def collapse(s, messages, my_idx):
		'''iterate backwards over recent messages and see if messages can be combined'''
		orig_msg = messages[my_idx]
		for layer in s.layers.values():
			msg = layer.collapse(messages, my_idx)
			if orig_msg is not msg:
				break
		return msg

	def absorb_msg(s, other_msg):
		global g_current_msg
		if g_current_msg is other_msg:
			g_current_msg = s
			s._log.extend(other_msg._log)
		if other_msg and other_msg is not s:
			s.absorbed.append(other_msg)
			if other_msg.absorbed:
				other_absorbed = other_msg.absorbed
				other_msg.absorbed = []
				for oa in other_absorbed:
					s.absorb_msg(oa)

	def identify_conns(s, messages, my_idx):
		msg = messages[my_idx]
		for layer_class in Layer.classes().values():
			if layer_class.proto not in msg.layers:
				continue
			layer_class.identify_conns(messages, my_idx)

	class EntityIdent:
		def __init__(s, proto=None, src_port=None, src_kind=None, src_entity=None, dst_port=None, dst_kind=None, dst_entity=None, rename=False):
			set_instance_vars_from_args()

	def identify_entities(s, messages, my_idx):
		'''From protocol and message discriminators, see if we can identify the src and dst port of the message
		to be of a specific core network entity.'''
		for layer in s.layers.values():
			try:
				identifieds = layer.identify_entities(s, messages, my_idx)
				if identifieds is None:
					continue
				if isinstance(identifieds, Message.EntityIdent):
					identifieds = [identifieds]

				for ident in identifieds:
					if ident is None:
						continue
					Entity.find_or_create(ident.proto, ident.src_kind,
								ident.src_port or s.src,
								ident.src_entity, from_msg=s,
								rename=(ident.rename is True or ident.rename == 'src'))
					Entity.find_or_create(ident.proto, ident.dst_kind,
								ident.dst_port or s.dst,
								ident.dst_entity, from_msg=s,
								rename=(ident.rename is True or ident.rename == 'dst'))
			except:
				raise Exception(f'In layer {layer} {s}')

	def find_entity(s, kind, with_port=None):
		for conn in (s.src_conns + s.dst_conns):
			ret = conn.find_entity(kind, with_port=with_port)
			if ret and ret[0] is not None:
				return ret
		return None, None

	def get_port(s, entity_kind:str):
		if s.src_entity_is(entity_kind):
			return s.src
		elif s.dst_entity_is(entity_kind):
			return s.dst
		return None

	def entity(s, *kinds):
		if s.src.entity and s.src.entity.kind in kinds:
			return s.src.entity
		if s.dst.entity and s.dst.entity.kind in kinds:
			return s.dst.entity

	def src_entity_is(s, *kinds):
		return s.src.entity and s.src.entity.kind in kinds

	def dst_entity_is(s, *kinds):
		return s.dst.entity and s.dst.entity.kind in kinds

	def same_src_dst(s, other, forward=None, reverse=None):
		# assume forward and reverse if neither are set.
		# if one of them is set to True, assume the other as False.
		if forward is None and reverse is None:
			forward = True
			reverse = True
		a = (s.src.key(), s.dst.key())
		b = (other.src.key(), other.dst.key())
		if forward and reverse:
			return set(a) == set(b)
		elif forward:
			return a == b
		elif reverse:
			return a == tuple(reversed(b))
		else:
			return False

	@classmethod
	def parse(cls, p:Packet):
		msg = Message(p)
		Layer.parse(msg)
		msg.src = msg.get_trait(('tcp','udp','sctp'), 'src')
		msg.dst = msg.get_trait(('tcp','udp','sctp'), 'dst')
		if msg.src is None or msg.dst is None:
			return None
		assert isinstance(msg.src, IpPort)
		assert isinstance(msg.dst, IpPort)
		return msg

	def label(s):
		label = []
		for l in s.layers.values():
			if not SHOW_ALL_LAYERS:
				if l.minor:
					continue
				if l.hidden and not all((ll.minor or ll.hidden) for ll in s.layers.values()):
					continue
			label.insert(0, l.label())
		return '/'.join(label)

	def related_subscribers(s):
		subscribers = UniqueList()
		src_sc = s.src_subscriber_conn()
		if src_sc:
			subscribers.append(src_sc.subscriber)
		dst_sc = s.dst_subscriber_conn()
		if dst_sc:
			subscribers.append(dst_sc.subscriber)
		for a in s.absorbed:
			subscribers.extend(a.related_subscribers())
		return subscribers

	def is_subscriber_related(s, subscriber):
		return subscriber in s.related_subscribers()

	def __repr__(s):
		return s.__str__()

	def __str__(s):
		return s.str()

	def str(s, ladder=False, one_column_per_kind=False, show_traits=True, show_conns=True):
		t_name = []
		t_name.extend(subscr.label() for subscr in s.related_subscribers())
		name = s.label()
		if name:
			t_name.append(name)

		src = str(s.src)
		dst = str(s.dst)

		if s.src.entity is not None:
			src_str = s.src.entity.label()
		else:
			src_str = src

		if s.count and dst == src:
			dst_str = '(self)'
		elif s.dst.entity is not None:
			dst_str = s.dst.entity.label()
		else:
			dst_str = dst

		src_pos = 0
		dst_pos = 0
		if s.src.entity:
			src_pos = s.src.entity.labelcolumn(one_column_per_kind)
		if s.dst.entity:
			dst_pos = s.dst.entity.labelcolumn(one_column_per_kind)

		# allows injecting informational fake messages (Entity.news)
		if not s.count and not s.count_back:
			dst_pos = src_pos

		if not s.src.entity and not s.dst.entity:
			if src > dst:
				src_pos = dst_pos + 1
			else:
				dst_pos = src_pos + 1

		if not ladder:
			if src_pos > dst_pos:
				src_pos = 1
				dst_pos = 0
			else:
				src_pos = 0
				dst_pos = 1

		if src_pos <= dst_pos:
			left_pos = src_pos
			right_pos = dst_pos
			left_label = src_str
			right_label = dst_str
			to_left_count = s.count_back
			to_right_count = s.count
		else:
			left_pos = dst_pos
			right_pos = src_pos
			left_label = dst_str
			right_label = src_str
			to_left_count = s.count
			to_right_count = s.count_back

		left_strs = []
		left_strs.append(left_label)
		if to_left_count:
			left_strs.append('<')
			if to_left_count > 1:
				left_strs.append(f'{to_left_count}')

		right_strs = []
		if to_right_count:
			if to_right_count > 1:
				right_strs.append(f'{to_right_count}')
			right_strs.append('>')
		right_strs.append(right_label)

		real_left_pos = max(0, left_pos - (len(left_label)//2))
		real_right_pos = right_pos - (len(right_label)//2) + len(right_label) + 1 - (len(right_label)&1)

		left_str = ''.join(left_strs)
		right_str = ''.join(right_strs)

		mid_gap = real_right_pos - real_left_pos - len(right_str) - len(left_str)
		mid_gap = max(1, mid_gap)

		if not ladder:
			mid_name_margin = 6
		else:
			mid_name_margin = mid_gap - len(name)
		if to_left_count or to_right_count:
			if mid_name_margin > 50:
				mid_gap_strs = ['-' * int(mid_name_margin // 2),
						name,
						'-' * int(mid_name_margin - (mid_name_margin//2))]
				name = ''
			else:
				mid_gap_strs = ['-' * int(mid_gap)]
		else:
			mid_gap_strs = []

		t = [' ' * int(real_left_pos),
		     left_str,]
		t.extend(mid_gap_strs)
		t.append(right_str)

		if ladder:
			t = [''.join(t)]
			right_end = len(t[0])
			label_pos = Entity.textcol_one_per_kind if one_column_per_kind else Entity.textcol_one_per_entity
			diff = label_pos - right_end
			if diff > 0:
				t.append(' ' * int(diff))

		if show_traits:
			if isinstance(show_traits, str):
				show_traits = [show_traits]
			for proto,l in s.layers.items():
				if not l.traits:
					continue
				if (show_traits is not True) and (proto not in show_traits):
					continue
				t_name.append('%s%s' % (proto, l.traits))

		if show_conns:
			conns = set()
			for c in (s.src_conns + s.dst_conns):
				conns.add(f'{c.proto}:{c.conn_id}')
				#conns.add(f'{c}')
			t_name.append(' '.join(conns))

		idxs = [s.p.idx] + [a.p.idx for a in s.absorbed]
		if len(idxs) <= 3:
			t_name.append('+'.join(str(i) for i in sorted(idxs)))
		else:
			t_name.append(f'{min(idxs)}-{max(idxs)}')
		t_name.append(f'{s.timestamp:.3f}')
		t.append(' ')
		t = [''.join(t)]
		indent = '\n' + (' ' * len(t[0]) + ' | ')
		t.append(' '.join(t_name))

		for l in s._log:
			t.append(indent)
			t.append(l)
		return ''.join(t)


	def src_subscriber_conn(s):
		for conn in s.src_conns:
			if conn.subscriber_conn is not None:
				return conn.subscriber_conn
		return None

	def dst_subscriber_conn(s):
		for conn in s.dst_conns:
			if conn.subscriber_conn is not None:
				return conn.subscriber_conn
		return None

	def find_message(s, proto, trait, value):
		for subscr_conn in (s.src_subscriber_conn(), s.dst_subscriber_conn()):
			if subscr_conn is None:
				continue
			msg = subscr_conn.find_message(proto, trait, value)
			if msg:
				return msg
		return None



class Entity:
	'''A core network program like BSC, MSC, ...'''
	KINDS_SORTING = ('MS', 'BTS', 'PCU', 'hNodeB', 'BSC', 'MGW@BSC', 'HNBGW', 'STP', 'MSC', 'MGW@MSC', 'MGW',
			 'SGSN', 'HLR', 'SIP', 'SIPcon', 'PBX', 'GGSN')
	KINDS_SORTING_EXIST = ()
	entities = listdict()
	state_version = 1 # whether to update cached text columns
	spacing = 5
	label_spacing = 2
	textcol_one_per_kind = 0
	textcol_one_per_entity = 0

	# proxy / forwarding addresses to ignore, like the STP port
	blacklist = []

	def __init__(s, kind:str):
		set_instance_vars_from_args()
		s.idx = None
		s.state_version = 0
		s.ports = listdict()
		s.labelcol_one_per_kind = 0
		s.labelcol_one_per_entity = 0
		Entity.add(s)

	@classmethod
	def add(cls, entity):
		Entity.entities.add(entity.kind, entity)
		entity.idx = entity.idx_in_kind()
		if entity.kind not in Entity.KINDS_SORTING_EXIST:
			# a new kind has come up, refresh Entity.KINDS_SORTING_EXIST
			exist = []
			for k in Entity.KINDS_SORTING:
				if k in Entity.entities.keys():
					exist.append(k)
			for k in Entity.entities.keys():
				if k not in exist:
					exist.append(k)
			Entity.KINDS_SORTING_EXIST = tuple(exist)

		Entity.state_version += 1

	@classmethod
	def count_entities(cls, kind):
		l = Entity.entities.get(kind)
		return len(l)

	@classmethod
	def add_to_blacklist(cls, port:IpPort):
		if port in cls.blacklist:
			return
		cls.blacklist.append(port);

	def rename(s, to_kind):
		Entity.entities.remove(s.kind, s)
		was_kind = s.kind
		s.kind = to_kind
		Entity.add(s)
		for proto,l in s.ports.items():
			for port in l:
				LOG(Color.colored('yellow', 'Rename port'), 'from', was_kind, 'to', s, proto, port)

	@classmethod
	def find_or_create(cls, proto, kind, port, matched_entity=None, from_msg=None, rename=False):
		if not port:
			return None
		if port in Entity.blacklist:
			return None

		found_entity = port.entity
		if found_entity and matched_entity and (found_entity is not matched_entity):
			LOG(Color.colored('purple', 'Renaming entity port:'), port, 'to', matched_entity)
		if not matched_entity:
			matched_entity = found_entity
		if matched_entity:
			if kind and matched_entity.kind != kind and rename:
				matched_entity.rename(kind)
			matched_entity.add_port(proto, port, from_msg=from_msg)
			return matched_entity

		if kind is None or rename:
			for l in Entity.entities.values():
				for e in l:
					if e.has_port(port):
						if kind and e.kind != kind and rename:
							e.rename(kind)
						return e

			if kind is None:
				return None
		else:
			l = Entity.entities.get(kind)
			if l:
				for e in l:
					if e.has_port(port):
						return e
		e = Entity(kind)
		e.add_port(proto, port, from_msg=from_msg)
		return e

	def absorb(s, other_entity):
		'''Merge two entities to one, adopting the other's ports'''
		for port in other_entity.ports:
			s.add_port(port)
		del other_entity

	def label(s):
		idx = ''
		if s.idx:
			idx = str(s.idx + 1)
		return f'{s.kind}{idx}'

	def __repr__(s):
		return s.label()
	def __str__(s):
		return repr(s)

	def kind_idx(s):
		'''this entity kind's position in the currently known entity kinds:
		For 'BSC', if we've seen BTS, BSC and MSC, return 1.'''
		return Entity.KINDS_SORTING_EXIST.index(s.kind)

	def idx_in_all(s):
		'''this entity kind's position in all currently known entities:
		For the second 'BSC', if we've seen 2 BTS, 3 BSC and 1 MSC, return 2 (BTS) + 1 (second BSC) = 3.'''
		idx = 0
		for k in Entity.KINDS_SORTING_EXIST:
			if k == s.kind:
				idx += Entity.entities.get(s.kind).index(s)
				return idx
			idx += Entity.count_entities(k)
		return idx

	def idx_in_kind(s):
		'''this entity kind's position in the list of entities of the same kind'''
		return Entity.entities.get(s.kind).index(s)

	def check_update_state(s):
		if s.state_version == Entity.state_version:
			return
		Entity.calculate_textcolumns()
		s.state_version = Entity.state_version

	def labelcolumn(s, one_column_per_kind=False, mid=True):
		s.check_update_state()
		if one_column_per_kind:
			midcol = s.labelcol_one_per_kind
		else:
			midcol = s.labelcol_one_per_entity

		if mid:
			ret = midcol
		else:
			ret = int(midcol - (len(s.label()) // 2))
		return ret

	@classmethod
	def calculate_textcolumns(cls):
		'''In text rendering of a ladder diagram, return the text column for this entity,
		if rendering each entity in its own column (not sharing one column per entity kind)'''
		entity_col = 0
		kind_col = 0
		for k in Entity.KINDS_SORTING_EXIST:
			l = Entity.entities.get(k)

			kind_col += len(k) // 2
			for e in l:
				e.labelcol_one_per_kind = kind_col
				Entity.textcol_one_per_kind = kind_col + len(e.label()) + Entity.spacing

				entity_col += len(e.kind)//2
				e.labelcol_one_per_entity = entity_col
				entity_col += len(e.label()) + Entity.spacing
				Entity.textcol_one_per_entity = entity_col

			kind_col += len(k) + Entity.spacing

	def has_port(s, port, proto=None):
		if proto:
			if port in s.ports.get(proto, []):
				return proto
			return None
		for proto,l in s.ports.items():
			if port in l:
				return proto
		return None

	def remove_port(s, port):
		for proto,l in s.ports.items():
			if port in l:
				l.remove(port)
				port.entity = None
				return

	def add_port(s, proto, port, from_msg=None):
		if port.entity and port.entity is not s:
			port.entity.remove_port(port)
		if s.has_port(port, proto=proto):
			return
		s.ports.add(proto, port)
		port.entity = s
		port.proto = proto
		LOG(Color.colored('cyan', 'New port:'), port)


class Subscriber:
	next_ident = 1
	next_tmsi_idx = 1
	imsis = {}
	tmsis = {}
	imeis = {}
	msisdns = {}

	def __init__(s, imsi:str=None, tmsi=None, imei=None, msisdn=None):
		set_instance_vars_from_args()
		s.subscriber_conns = UniqueList()
		s.tmsis = set()
		s.tmsi_idx = 0
		s.set_last_tmsi(tmsi)
		s.ident = Subscriber.next_ident
		Subscriber.next_ident += 1
		Subscriber.update_dicts(s)

	def set_last_tmsi(s, tmsi):
		if tmsi is None:
			return
		s.tmsi = tmsi
		if (not isinstance(tmsi, str)) or len(str(tmsi)) < 8:
			raise Exception('Invalid TMSI: ' + str(tmsi))
		s.tmsi_idx = Subscriber.next_tmsi_idx
		Subscriber.next_tmsi_idx += 1
		s.tmsis.add(tmsi)
		Subscriber.tmsis[s.tmsi] = s

	@classmethod
	def update_dicts(cls, s):
		if s.imsi:
			Subscriber.imsis[s.imsi] = s
		for tmsi in s.tmsis:
			Subscriber.tmsis[tmsi] = s
		if s.imei:
			Subscriber.imeis[s.imei] = s
		if s.msisdn:
			Subscriber.msisdns[s.msisdn] = s

	def label(s, full=False):
		l = []
		if full or (not s.imsi and not s.tmsi and not s.imei and not s.msisdn):
			l.append(f'subscr{s.ident}')
		if s.imsi and (full or not s.msisdn):
			l.append(f'imsi{s.imsi}')

		if s.tmsi and (full or not s.imsi):
			l.append(f'tmsi{s.tmsi}')
		if s.imei and (full or (not s.imsi and not s.tmsi)):
			l.append(f'imei{s.imei}')
		if s.msisdn:
			l.append(f'msisdn{s.msisdn}')
		return Color.colored(s.ident, ':'.join(l))

	def __repr__(s):
		return s.label(full=True)
	def __str__(s):
		return s.label()

	@classmethod
	def identify_subscriber(cls, msg:Message):
		imsi = msg.get_trait(('dtap','bssmap','rsl','gsup'), 'imsi')
		tmsi = tmsi_standardize(msg.get_trait(('dtap','bssmap','rsl'), 'tmsi'))
		imei = msg.get_trait('dtap', 'imei')
		msisdn = msg.get_trait('gsup', 'msisdn')

		if not (imsi or tmsi or imei or msisdn):
			return
		#if not msg.src_conns and not msg.dst_conns:
		#	return

		# could start out with subscr = None, but to use a few less subscriber.ids start out with a present
		# subscriber, if any.
		subscr_conn = msg.src_subscriber_conn() or msg.dst_subscriber_conn()
		if subscr_conn is not None:
			subscr = subscr_conn.subscriber
		else:
			subscr = None

		if imsi:
			subscr = Subscriber.merge(Subscriber.by_imsi(imsi), subscr)
		if tmsi:
			subscr = Subscriber.merge(Subscriber.by_tmsi(tmsi), subscr)
		if imei:
			subscr = Subscriber.merge(Subscriber.by_imei(imei), subscr)
		if msisdn:
			subscr = Subscriber.merge(Subscriber.by_msisdn(msisdn), subscr)

		if subscr is None:
			return
		if subscr_conn is None:
			subscr_conn = SubscriberConn()
		subscr_conn.set_subscriber(subscr)

		for c in (msg.src_conns + msg.dst_conns):
			if c.subscriber_conn is None:
				subscr_conn.add_conn(c)
				c.subscriber_conn = subscr_conn
			else:
				c.subscriber_conn = SubscriberConn.merge(c.subscriber_conn, subscr_conn)

	@classmethod
	def by_imsi(cls, imsi):
		subscr = Subscriber.imsis.get(imsi)
		if not subscr:
			subscr = Subscriber(imsi=imsi)
		return subscr

	@classmethod
	def by_tmsi(cls, tmsi):
		subscr = Subscriber.tmsis.get(tmsi)
		if not subscr:
			subscr = Subscriber(tmsi=tmsi)
		return subscr

	@classmethod
	def by_imei(cls, imei):
		subscr = Subscriber.imeis.get(imei)
		if not subscr:
			subscr = Subscriber(imei=imei)
		return subscr

	@classmethod
	def by_msisdn(cls, msisdn):
		subscr = Subscriber.msisdns.get(msisdn)
		if not subscr:
			subscr = Subscriber(msisdn=msisdn)
		return subscr

	@classmethod
	def merge(cls, a, b):
		assert a is None or isinstance(a, Subscriber)
		assert b is None or isinstance(b, Subscriber)
		if a is None and b is None:
			return None
		if a is None:
			return b
		if b is None or b is a:
			return a

		if not a.imsi and a.ident > b.ident:
			return cls.merge(b, a)

		if a.imsi and b.imsi and a.imsi != b.imsi:
			out_error(f'cannot absorb, subscriber would change IMSI: {b.imsi} -> {a.imsi}')
			return None
		if a.imei and b.imei and a.imei != b.imei:
			out_error(f'cannot absorb, subscriber would change IMEI: {b.imei} -> {a.imei}')
			return None

		if b.imsi:
			a.imsi = b.imsi
			b.imsi = None

		if b.tmsis:
			a.tmsis.update(b.tmsis)
			b.tmsis = set()
			if b.tmsi_idx > a.tmsi_idx:
				a.set_last_tmsi(b.tmsi)
			b.tmsi = None

		if b.imei:
			a.imei = b.imei
			b.imei = None

		if b.msisdn:
			if a.msisdn and a.msisdn != b.msisdn:
				LOG(f'subscriber {a} changes MSISDN: {a.msisdn} -> {b.msisdn}')
			a.msisdn = b.msisdn
			b.msisdn = None

		Subscriber.update_dicts(a)

		for sc in b.subscriber_conns:
			a.add_subscriber_conn(sc)
		b.subscriber_conns = []
		return a

	def add_subscriber_conn(s, subscriber_conn):
		if subscriber_conn.subscriber is s:
			return
		if subscriber_conn.subscriber:
			subscriber_conn.subscriber.subscriber_conns.remove(subscriber_conn)
		s.subscriber_conns.append(subscriber_conn)
		subscriber_conn.subscriber = s
		assert subscriber_conn in subscriber_conn.subscriber.subscriber_conns

	def find_entity(s, kind, with_port=None):
		for subscriber_conn in reversed(s.subscriber_conns):
			found, found_subscriber_conn = subscriber_conn.find_entity(kind, ask_subscriber=False,
										   with_port=with_port)
			if found is not None:
				return found, found_subscriber_conn
		return None, None

class SubscriberConn:
	'''A SubscriberConn is a collection of conns that feed into each other.
	For example, the Abis and the BSSMAP link for the same subscriber are related, as well as the MGCP and
	RTP spoken for that subscriber.
	If a subscriber disconnects and connects again, that is a new separate SubscriberConn;
	also if a subscriber would concurrently attach in twice somehow, that would be separate SubscriberConn
	instances.

	Note that a Message's src_conns and a dst_conns are not necessarily listed in the same SubscriberConn, for example
	for RTP, SIP or SMS, the messages may pass from one subscriber to another.'''

	def __init__(s, subscriber=None):
		set_instance_vars_from_args()
		s.conns = UniqueList()

	@classmethod
	def merge(cls, a, b):
		assert a is None or isinstance(a, SubscriberConn)
		assert b is None or isinstance(b, SubscriberConn)
		if a is None and b is None:
			return None
		if a is None:
			return b
		if b is None or b is a:
			return a
		b_subscr = b.subscriber
		if b.subscriber:
			b.subscriber.subscriber_conns.remove(b)
			b.subscriber = None
		a.subscriber = Subscriber.merge(a.subscriber, b_subscr)
		if a.subscriber:
			a.subscriber.subscriber_conns.append(a)
		for conn in b.conns:
			conn.subscriber_conn = a
			a.conns.append(conn)
		b.conns = None
		return a

	def find_entity(s, kind, with_port=None, ask_subscriber=True):
		if ask_subscriber and s.subscriber is not None:
			return s.subscriber.find_entity(kind, with_port=with_port)
		if with_port is not None and isinstance(with_port, str):
			with_port = [with_port]
		for conn in reversed(s.conns):
			if with_port is not None and conn.port.proto not in with_port:
				continue
			if conn.port.entity is not None and conn.port.entity.kind == kind:
				return conn.port.entity, s
		return None, None

	def find_message(s, proto, trait, val):
		for conn in reversed(s.conns):
			for msgs in (conn.tx_messages, conn.rx_messages):
				for msg in msgs:
					for p, t, v in msg.get_traits(proto, trait):
						if val is None or val == v:
							return msg
		return None

	def set_subscriber(s, subscriber):
		s.subscriber = subscriber
		if subscriber is not None:
			subscriber.subscriber_conns.append(s)

	def add_conn(s, conn):
		s.conns.append(conn)
		conn.subscriber_conn = s

	def __repr__(s):
		return f'{s.subscriber}~{s.conns}'


class Layer_tcp(Layer):
	def __init__(s, msg:Message):
		p = msg.p
		traits = Traits(
			src=IpPort.from_tcp_source(p),
			dst=IpPort.from_tcp_dest(p),
			)
		super().__init__(msg=msg, proto='tcp', msgtype=None, traits=traits, minor=True)

class Layer_udp(Layer):
	def __init__(s, msg:Message):
		p = msg.p
		traits = Traits(
			src=IpPort.from_udp_source(p),
			dst=IpPort.from_udp_dest(p),
			)
		super().__init__(msg=msg, proto='udp', msgtype=None, traits=traits, minor=True)

class Layer_sctp(Layer):
	def __init__(s, msg:Message):
		p = msg.p
		traits = Traits(
			src=IpPort.from_sctp_source(p),
			dst=IpPort.from_sctp_dest(p),
			stream_id = p.get('sctp.data_sid'),
			stream_seq = p.get('sctp.data_ssn'),
			)
		super().__init__(msg=msg, proto='sctp', msgtype=None, traits=traits, minor=True)

class Layer_rtp(Layer):
	def __init__(s, msg:Message):
		pt = msg.p.get('rtp.p_type')

		iuup_msgtype = sane_showname(msg.p.get('iuup.pdu_type.showname'))

		if iuup_msgtype is not None:
			msgtype = f'{pt}.{iuup_msgtype}'
		else:
			msgtype = pt

		traits = Traits(
			pt=pt,
			iuup=iuup_msgtype
			)
		super().__init__(msg=msg, proto='rtp', msgtype=msgtype, traits=traits)

	def collapse(s, messages, my_idx):
		msgtype = s.msg.get_trait('rtp', 'msgtype')
		src = s.msg.src
		dst = s.msg.dst
		for i in reversed(range(my_idx)):
			prev_msg = messages[i]
			if not prev_msg:
				continue
			if prev_msg.finalized:
				break
			if not 'rtp' in prev_msg.layers:
				if prev_msg.is_minor():
					continue
				else:
					break
			if prev_msg.get_trait('rtp', 'msgtype') != msgtype:
				continue
			if s.msg.same_src_dst(prev_msg, forward=True):
				# found a recent RTP similar RTP packet, combine
				prev_msg.count += 1
				messages[my_idx] = None
				prev_msg.absorb_msg(s.msg)
				return prev_msg
			if 1 and s.msg.same_src_dst(prev_msg, reverse=True):
				# same but backwards
				prev_msg.count_back += 1
				messages[my_idx] = None
				prev_msg.absorb_msg(s.msg)
				return prev_msg
		return s.msg

	# identify_entities: RTP ports are identified by watching RSL and MGCP, see Layer_gsm_abis_rsl.identify_conns_rtp

	@classmethod
	def identify_conns(cls, messages:list, my_idx:int):
		msg = messages[my_idx]

		conn = Conn.find('rtp', msg.src, conn_id=msg.src.key())
		if conn is not None:
			conn.add_message(msg)

		conn = Conn.find('rtp', msg.dst, conn_id=msg.dst.key())
		if conn is not None:
			conn.add_message(msg)

class Layer_mgcp(Layer):
	def __init__(s, msg:Message):
		p = msg.p
		verb = p.get('mgcp.req_verb')
		rsp = p.get('mgcp.rsp_rspstring')
		msgtype = verb or rsp or '?'
		tid = p.get('mgcp.transid', '')

		rtp_port = None
		sdp_rtp_ip = p.get('sdp.connection_info_address')
		sdp_rtp_port = p.get('sdp.media_port')
		if sdp_rtp_ip and sdp_rtp_port:
			rtp_port = IpPort.get(sdp_rtp_ip, sdp_rtp_port)

		if rsp:
			endp = p.get('mgcp.param_specificendpointid')
		else:
			endp = p.get('mgcp.req_endpoint')
			if endp and endp.startswith('rtpbridge/*@'):
				endp = None
		traits = Traits(
			tid=tid,
			endp=endp,
			ci=p.get('mgcp.param_connectionid'),
			verb=verb,
			rsp=rsp,
			rtp_port=rtp_port,
			)

		s.tid = tid
		super().__init__(msg=msg, proto='mgcp', msgtype=msgtype, traits=traits)

	def label(s):
		return f'mgcp.{s.tid}.{s.msgtype}'

	def identify_entities(s, msg:Message, messages, my_idx):
		if msg.get_trait('mgcp', 'verb') == 'CRCX':
			dst_kind = 'MGW'
			if msg.src_entity_is('BSC'):
				dst_kind = 'MGW@BSC'
			elif msg.src_entity_is('MSC'):
				dst_kind = 'MGW@MSC'
			return Message.EntityIdent(proto='mgcp', dst_kind=dst_kind)
		elif msg.get_trait('mgcp', 'rsp') and msg.src_entity_is('MGW', 'MGW@BSC','MGW@MSC'):
			rtp = msg.get_trait('mgcp', 'rtp_port')
			if rtp:
				msg.src.entity.add_port('rtp', rtp)
		return None

	@classmethod
	def find_req(cls, messages, my_idx):
		msg = messages[my_idx]
		for match in find_same_trait(msg, messages, my_idx, 'mgcp', 'tid'):
			if match.get_trait('mgcp', 'rsp'):
				continue
			if not match.same_src_dst(msg, reverse=True):
				continue
			return match
		return None

	@classmethod
	def identify_conns(cls, messages:list, my_idx:int):
		msg = messages[my_idx]
		proto = 'mgcp'

		if msg.get_trait('mgcp', 'verb'):
			endp = msg.get_trait('mgcp', 'endp')
			mgw_port = msg.dst
			endp_conn = Conn.find(proto, mgw_port, endp)
			if endp_conn is not None:
				endp_conn.add_message(msg)
				for c in (msg.src_conns + msg.dst_conns):
					endp_conn.merge_subscr_conns(c)

			ci = msg.get_trait('mgcp', 'ci')
			conn_id = f'{endp}:{ci}'
			conn = Conn.find(proto, mgw_port, conn_id)
			if conn:
				conn.add_message(msg)
				for c in (msg.src_conns + msg.dst_conns + msg.meta_conns):
					conn.merge_subscr_conns(c)

		if msg.get_trait('mgcp', 'rsp') == 'OK':
			req = cls.find_req(messages, my_idx)
			if req is None:
				ERR('MGCP response without request')
				return
			mgw_port = req.dst

			verb = req.get_trait('mgcp', 'verb')
			if verb == 'CRCX':
				# The MGCP connection
				endp = msg.get_trait('mgcp', 'endp') or req.get_trait('mgcp', 'endp')
				ci = msg.get_trait('mgcp', 'ci')
				if not endp or not ci:
					ERR('MGCP CRCX with endp =', endp, 'ci =', ci)

				# creating two levels of conn: a meta conn with just endp,
				# and a proper one with endp+ci
				# endp:
				endp_conn = Conn.find(proto, mgw_port, endp)
				if not endp_conn:
					endp_conn = Conn.open(proto, mgw_port, conn_id=endp, start_msg=msg)

				# endp+ci:
				conn_id = f'{endp}:{ci}'
				conn = Conn.find(proto, mgw_port, conn_id)
				if not conn:
					conn = Conn.open(proto, mgw_port, conn_id, msg)
				conn.add_message(req)
				conn.add_message(msg)
				conn.merge_subscr_conns(endp_conn)

				# The RTP connection set up by MGCP
				rtp_port = msg.get_trait('mgcp', 'rtp_port')
				if rtp_port:
					rtp_conn = Conn.open('rtp', rtp_port, conn_id=rtp_port.key(), start_msg=msg, merge_counterparts=False,
							     entity=conn.port.entity)
					rtp_conn.merge_subscr_conns(conn)
					# bssmap or ranap layer will mention this rtp_port in their Assignment / RAB-Assignment

			else:
				endp = req.get_trait('mgcp', 'endp')
				ci = req.get_trait('mgcp', 'ci')
				Conn.message(proto, mgw_port, endp, msg)

				conn_id = f'{endp}:{ci}'
				Conn.message(proto, mgw_port, conn_id, msg)

				if verb == 'DLCX':
					# The MGCP connection
					endp = req.get_trait('mgcp', 'endp')
					ci = req.get_trait('mgcp', 'ci')
					if not endp:
						ERR('MGCP DLCX without endp')

					def close_ci(ci):
						ci_conn_id = f'{endp}:{ci}'
						# go through all RTP ports created in this conn
						ci_conn = Conn.find(proto, mgw_port, ci_conn_id)
						if ci_conn is not None:
							all_rtp_ports = UniqueList()
							for msgs in (ci_conn.rx_messages, ci_conn.tx_messages):
								for msg in msgs:
									all_rtp_ports.append(msg.get_trait('mgcp', 'rtp_port'))

							for rtp_port in all_rtp_ports:
								Conn.close('rtp', rtp_port, conn_id=rtp_port.key(), close_msg=msg, if_exists=True)
							Conn.close(proto, mgw_port, ci_conn_id, msg)

					if ci:
						close_ci(ci)
					else:
						endp_conn = Conn.find(proto, mgw_port, endp)
						all_ci = UniqueList()
						if endp_conn:
							for msgs in (endp_conn.tx_messages, endp_conn.rx_messages):
								for msg in msgs:
									all_ci.append(msg.get_trait('mgcp', 'ci'))
						for ci in all_ci:
							close_ci(ci)

					Conn.close(proto, mgw_port, endp, msg, if_exists=True)


		elif msg.get_trait('mgcp', 'verb') == 'MDCX':
			# The RTP connection set up by BSC or MSC
			rtp_port = msg.get_trait('mgcp', 'rtp_port')
			if rtp_port and Conn.find('rtp', rtp_port, conn_id=rtp_port.key()) is None:
				rtp_conn = Conn.open('rtp', rtp_port, conn_id=rtp_port.key(), start_msg=msg, merge_counterparts=False)
				for c in msg.src_conns:
					rtp_conn.merge_subscr_conns(c)

class Layer_sccp(Layer):
	def __init__(s, msg:Message):
		p = msg.p
		msgtype = p.get('sccp.message_type.showname')
		traits = Traits(
			src_lref=p.get('sccp.slr'),
			dst_lref=p.get('sccp.dlr'),
			)
		super().__init__(msg=msg, proto='sccp', msgtype=msgtype, traits=traits, hidden=True)

	def collapse(s, messages, my_idx):
		msg = s.msg

		# cut out STP hop
		if SCCP_COLLAPSE_STP:
			src = msg.src
			t = msg.timestamp
			for i in reversed(range(my_idx)):
				prev_msg = messages[i]
				if not prev_msg:
					continue
				if t - prev_msg.timestamp > 1:
					break
				if prev_msg.absorbed:
					continue
				prev_sccp = prev_msg.layers.get(s.proto, None)
				if prev_sccp is None:
					continue
				#if src != prev_msg.dst:
				#	continue
				if s.msgtype != prev_sccp.msgtype:
					continue
				if not msg.same_traits(prev_msg, 'sccp', ('src_lref', 'dst_lref'), allow_unset=True):
					continue
				if not msg.same_traits(prev_msg, 'sctp', 'stream_id'):
					continue
				if not msg.same_traits(prev_msg, 'm3ua', ('opc', 'dpc')):
					continue
				if not msg.same_traits(prev_msg, 'm3ua', 'message_length'):
					continue

				prev_msg.set_trait('sctp', 'dst', msg.get_trait('sctp', 'dst'))
				prev_msg.dst = msg.dst
				prev_msg.absorb_msg(msg)
				messages[i] = None
				messages[my_idx] = prev_msg
				Entity.add_to_blacklist(src)
				return prev_msg
		return msg

	@classmethod
	def identify_conns(cls, messages:list, my_idx:int):
		msg = messages[my_idx]
		proto = 'sccp'
		msgtype = msg.get_trait(proto, 'msgtype')
		if SCCP_COLLAPSE_STP and not msg.absorbed:
			return
		src_id = msg.get_trait(proto, 'src_lref')
		dst_id = msg.get_trait(proto, 'dst_lref')
		if msgtype == 'Connection-Request':
			Conn.open(proto, msg.src, src_id, msg)
		elif msgtype == 'Connection-Confirm':
			Conn.open(proto, msg.src, src_id, msg,
				counterparts=[Conn.find(proto, msg.dst, dst_id)])
		elif msgtype in ('Release-Complete',):
			Conn.close(proto, msg.src, src_id, msg)
		else:
			if src_id:
				Conn.message(proto, msg.src, src_id, msg)
			if dst_id:
				Conn.message(proto, msg.dst, dst_id, msg)


class Layer_m3ua(Layer):
	def __init__(s, msg:Message):
		traits = Traits(
			opc = msg.p.get('m3ua.protocol_data_opc'),
			dpc = msg.p.get('m3ua.protocol_data_dpc'),
			message_length = msg.p.get('m3ua.message_length'),
			)
		super().__init__(msg=msg, proto='m3ua', msgtype=None, traits=traits, minor=True)

# wireshark commonly falsely classifies a BSSMAP Ciphering Mode Command as RNSAP PDU
class Layer_rnsap(Layer):
	def __init__(s, msg:Message):
		p = msg.p
		traits = Traits()
		msgtype = 'Cipher Mode Command'
		super().__init__(msg=msg, proto='bssmap', msgtype=msgtype, traits=traits)

class Layer_bssap(Layer):
	'BSSAP, either BSS Management (see Layer_gsm_a_bssmap) or Direct Transfer (see Layer_gsm_a_dtap)'
	def __init__(s, msg:Message):
		msgtype = msg.p.get('bssap.msgtype.showname')
		msgtype = msg.p.get('bssap.pdu_type.showname')

		traits = Traits(
			msgtype_nr=int(msg.p.get('bssap.pdu_type'), 16),
			)

		super().__init__(msg=msg, proto='bssap', msgtype=msgtype, traits=traits, minor=True)

class Layer_bssgp(Layer):
	def __init__(s, msg:Message):
		msgtype = sane_msgtype(msg.p.get('bssgp.pdu_type.showname'))
		traits = Traits(
				tlli=msg.p.get('bssgp.gsm_a_rr_tlli'),
			)
		super().__init__(msg=msg, proto='bssgp', msgtype=msgtype, traits=traits)

	def identify_entities(s, msg:Message, messages, my_idx):
		if msg.get_trait('bssgp', 'msgtype') == 'FLOW-CONTROL-BVC':
			return Message.EntityIdent(proto='bssgp', src_kind='PCU', dst_kind='SGSN')
		return None

	@classmethod
	def identify_conns(cls, messages:list, my_idx:int):
		msg = messages[my_idx]
		proto = 'bssgp'
		msgtype = msg.get_trait('dtap', 'msgtype')
		tlli = msg.get_trait('bssgp', 'tlli')
		conn_id = tlli
		if not conn_id:
			return
		if msgtype == 'Attach-Request':
			Conn.open(proto, msg.src, conn_id, msg,
				  counterparts=[Conn.open(proto, msg.dst, conn_id, msg)])
		elif msgtype == 'Attach-Accept':
			conn = Conn.close(proto, msg.src, conn_id, msg)
			new_conn_id = msg.get_trait('dtap', 'tmsi')
			new_conn = Conn.open(proto, msg.src, new_conn_id, msg,
				  counterparts=[Conn.open(proto, msg.dst, new_conn_id, msg)])
			new_conn.merge_subscr_conns(conn)
		elif msgtype == 'Attach-Complete':
			Conn.close(proto, msg.src, conn_id, msg)
		else:
			conn = Conn.message(proto, msg.src, conn_id, msg)




class Layer_hnbap(Layer):
	def __init__(s, msg:Message):
		def strip_till_dash(dashstr):
			if not dashstr or not '-' in dashstr:
				return dashstr
			dash = dashstr.rindex('-')
			return dashstr[dash+1:]

		msgtype = strip_till_dash(msg.p.get('hnbap.procedurecode.showname'))
		pdutype = strip_till_dash(sane_msgtype(msg.p.get('hnbap.hnbap_pdu.showname')))
		pdutype_nr = msg.p.get('hnbap.hnbap_pdu')
		traits = Traits(
			msgtype_nr=int(msg.p.get('hnbap.procedurecode')),
			pdutype=pdutype,
			pdutype_nr=int(pdutype_nr),
			)
		super().__init__(msg=msg, proto='hnbap', msgtype=msgtype, traits=traits)

	def identify_entities(s, msg:Message, messages, my_idx):
		if (msg.get_trait('hnbap', 'msgtype') in ('Register', 'HNBRegister', 'UERegister')) and (msg.get_trait('hnbap', 'pdutype_nr') == 0):
			return Message.EntityIdent(proto='Iuh', src_kind='hNodeB', dst_kind='HNBGW')
		return None

class Layer_rua(Layer):
	def __init__(s, msg:Message):
		def strip_till_dash(dashstr):
			if not dashstr or not '-' in dashstr:
				return dashstr
			dash = dashstr.rindex('-')
			return dashstr[dash+1:]

		msgtype = strip_till_dash(msg.p.get('rua.procedurecode.showname'))
		pdutype = strip_till_dash(sane_msgtype(msg.p.get('rua.rua_pdu.showname')))
		pdutype_nr = msg.p.get('rua.rua_pdu')
		cn_domain_i = msg.p.get('rua.cn_domainindicator')
		cn_domain = None
		if cn_domain_i == '0':
			cn_domain = 'cs'
		elif cn_domain_i == '1':
			cn_domain = 'ps'
		traits = Traits(
			msgtype_nr=int(msg.p.get('rua.procedurecode')),
			pdutype=pdutype,
			cn_domain=cn_domain,
			rua_ctx=msg.p.get('rua.context_id'),
			)
		super().__init__(msg=msg, proto='rua', msgtype=msgtype, traits=traits, cap_p_name='rua')

	@classmethod
	def identify_conns(cls, messages:list, my_idx:int):
		msg = messages[my_idx]
		proto = 'rua'
		msgtype = msg.get_trait(proto, 'msgtype')
		conn_id = (msg.get_trait(proto, 'cn_domain') or '?') + ':' + (msg.get_trait(proto, 'rua_ctx') or '?')
		if msgtype == 'Connect':
			conn = Conn.open(proto, msg.src, conn_id, msg)
			Conn.open(proto, msg.dst, conn_id, msg, counterparts=[conn])
		elif msgtype == 'Disconnect':
			Conn.close(proto, msg.dst, conn_id, msg)
		else:
			Conn.message(proto, msg.src, conn_id, msg)


class Layer_ranap(Layer):
	def __init__(s, msg:Message):
		msgtype = msg.p.get('ranap.rab_assignmentrequest_element'
			) or msg.p.get('ranap.rab_assignmentresponse_element'
			) or msg.p.get('ranap.initiatingmessage_element')

		rtp_port = None
		ip = msg.p.get('ranap.nsap_ipv4_addr')
		port_bin = msg.p.get('ranap.bindingid.binary_value')
		if ip and port_bin and len(port_bin) >= 2:
			port = int.from_bytes(port_bin[:2], "big")
			rtp_port = IpPort.get(ip, port)

		traits = Traits(
			rtp_port=rtp_port,
			)
		super().__init__(msg=msg, proto='ranap', msgtype=msgtype, traits=traits)

	def collapse(s, messages, my_idx):
		msg = s.msg

		# cut out HNBGW hop
		if IUH_COLLAPSE_HNBGW:
			src = msg.src
			t = msg.timestamp
			for i in reversed(range(my_idx)):
				prev_msg = messages[i]
				if not prev_msg:
					continue
				if t - prev_msg.timestamp > 1:
					break
				if src != prev_msg.dst:
					continue
				if msg.src.entity is not prev_msg.dst.entity:
					continue
				# DOESNT WORK
				if not msg.same_traits(prev_msg, 'ranap', None):
					continue
				if not msg.same_traits(prev_msg, 'sccp', ('src_lref', 'dst_lref'), allow_unset=True):
					continue
				if not msg.same_traits(prev_msg, 'sctp', 'stream_id'):
					continue
				if not msg.same_traits(prev_msg, 'm3ua', ('opc', 'dpc')):
					continue

				prev_msg.set_trait('sctp', 'dst', msg.get_trait('sctp', 'dst'))
				prev_msg.dst = msg.dst
				prev_msg.absorb_msg(msg)
				messages[i] = None
				messages[my_idx] = prev_msg
				Entity.add_to_blacklist(src)
				return prev_msg
		return msg

	def identify_entities(s, msg:Message, messages, my_idx):
		ids = []
		ids.append(s.identify_attach(msg, messages, my_idx))

		msgtype = msg.get_trait('ranap', 'msgtype')
		rtp_port = msg.get_trait('ranap', 'rtp_port')

		if rtp_port and msgtype == 'RAB-AssignmentRequest':
			# associate the MSC's MGCP port, but take care to not say the STP is an MSC
			crcx_ok = msg.find_message('mgcp', 'rtp_port', rtp_port)
			if crcx_ok and crcx_ok.src_entity_is('MGW'):
				mgw = crcx_ok.src.entity

				msc = None
				if msg.src_entity_is('MSC'):
					msc = msg.src.entity

				ids.append(Message.EntityIdent(proto='mgcp', src_port=crcx_ok.src, src_entity=mgw, src_kind='MGW@MSC', rename=True,
						dst_entity=msc, dst_port=crcx_ok.dst if msc else None))

		if rtp_port and msgtype == 'RAB-AssignmentResponse' and msg.src_entity_is('hNodeB'):
			ids.append(Message.EntityIdent(proto='rtp', src_kind='hNodeB', src_port=rtp_port, src_entity=msg.src.entity))

		return ids

	def identify_attach(s, msg:Message, messages, my_idx):
		ids = []
		dst_kind = None
		msgtype = msg.get_trait('dtap', 'msgtype')
		if msgtype in DTAP_COMPL_L3:
			dst_kind = 'MSC'
			proto = 'IuCS'
		elif msgtype in GMM_COMPL_L3:
			dst_kind = 'SGSN'
			proto = 'IuPS'

		if not dst_kind:
			return None

		if 'rua' in msg.layers:
			return Message.EntityIdent(proto='Iuh', src_kind='hNodeB', dst_kind='HNBGW')

		# don't mistake the STP as MSC or SGSN
		if SCCP_COLLAPSE_STP and not msg.absorbed:
			return None
		if not SCCP_COLLAPSE_STP and msg.src_entity_is('HNBGW'):
			return None

		# FIXME: below only makes sense with SCCP_COLLAPSE_STP == True
		if not SCCP_COLLAPSE_STP:
			return None

		# find a HNBGW that has recently received the same LU,
		# associate IuCS port
		src_entity = None
		for match in find_same_trait(msg, messages, my_idx, 'dtap', None):
			if 'rua' not in match.layers:
				continue
			if not match.dst_entity_is('HNBGW'):
				continue
			src_entity = match.dst.entity
			if src_entity:
				break

		return Message.EntityIdent(proto=proto, src_kind='HNBGW', src_entity=src_entity, dst_kind=dst_kind)

	@classmethod
	def identify_conns(cls, messages, my_idx):
		msg = messages[my_idx]

		if SCCP_COLLAPSE_STP and not msg.absorbed:
			return

		rtp_port = msg.get_trait('ranap', 'rtp_port')
		if rtp_port:
			rtp_conn = Conn.find('rtp', rtp_port, rtp_port.key())
			if rtp_conn:
				for c in msg.src_conns:
					rtp_conn.merge_subscr_conns(c)


class Layer_gsm_a_bssmap(Layer):
	def __init__(s, msg:Message):
		p = msg.p
		msgtype = p.get('gsm_a_bssmap.msgtype.showname')

		rtp_port = None
		ip = p.get('gsm_a_bssmap.aoip_trans_ipv4')
		port = p.get('gsm_a_bssmap.aoip_trans_port')
		if ip and port:
			rtp_port = IpPort.get(ip, port)

		tmsi = tmsi_standardize(p.get('gsm_a_bssmap.gsm_a_tmsi'))

		traits = Traits(
			msgtype_nr=str_to_int(p.get('gsm_a_bssmap.msgtype')),
			rtp_port=rtp_port,
			imsi=p.get('gsm_a_bssmap.e212_imsi'),
			tmsi=tmsi,
			)
		super().__init__(msg=msg, proto='bssmap', msgtype=msgtype, traits=traits, cap_p_name='gsm_a_bssmap')

	def identify_entities(s, msg:Message, messages, my_idx):
		# don't mistake the STP as MSC or BSC
		if SCCP_COLLAPSE_STP and not msg.absorbed:
			return None

		msgtype = msg.get_trait('bssmap', 'msgtype')
		if msgtype in ('Complete-Layer-3-Information', 'Clear-Complete'):

			# associate BSC BSSMAP port with BSC RSL port
			src_entity = None
			for match in find_same_trait(msg, messages, my_idx, 'dtap', ('tmsi', 'imsi')):
				if 'rsl' not in match.layers:
					continue
				if not match.dst.entity or match.dst.entity.kind != 'BSC':
					continue
				src_entity = match.dst.entity
				if src_entity:
					break

			return Message.EntityIdent(proto='bssmap', src_kind='BSC', dst_kind='MSC', src_entity = src_entity)

		if msgtype == 'Assignment-Request':
			# This Assignment-Request's rtp_port should match an earlier MGCP CRCX-OK message, and we now
			# know that this MSC asked for it.
			rtp_port = msg.get_trait('bssmap', 'rtp_port')
			if not rtp_port:
				return None

			def cond(prev_msg):
				return prev_msg.get_trait('mgcp', 'rtp_port') == rtp_port
			crcx_ok = None
			for prev_msg in find_recent_msg(msg, messages, my_idx, cond):
				crcx_ok = prev_msg
				break
			if not crcx_ok:
				return None
			msc = msg.src.entity
			mgw = crcx_ok.src.entity
			return Message.EntityIdent(proto='mgcp', src_port=crcx_ok.src, src_entity=mgw, src_kind='MGW@MSC', rename=True,
					dst_port=crcx_ok.dst, dst_entity=msc, dst_kind='MSC')


		return None

	@classmethod
	def identify_conns(cls, messages, my_idx):
		msg = messages[my_idx]
		msgtype = msg.get_trait('bssmap', 'msgtype')

		if SCCP_COLLAPSE_STP and not msg.absorbed:
			return

		# Paging does not have a proper end, it may never be answered.
		# The RSL paging command hopefully happens, and closes this Conn.
		if msgtype == 'Paging':
			imsi = msg.get_trait('bssmap', 'imsi')
			if imsi is not None:
				c = Conn.open('bssmap', msg.dst, f'page_imsi{imsi}', msg)
				Conn.close_conn(c, msg)
			tmsi = msg.get_trait('bssmap', 'tmsi')
			if tmsi is not None:
				c = Conn.open('bssmap', msg.dst, f'page_tmsi{tmsi}', msg)
				Conn.close_conn(c, msg)

		rtp_port = msg.get_trait('bssmap', 'rtp_port')
		if rtp_port is None:
			return

		rtp_conn = Conn.find('rtp', rtp_port, rtp_port.key())
		if rtp_conn is None:
			return
		for c in msg.src_conns:
			rtp_conn.merge_subscr_conns(c)

		def cond(prev_msg):
			return prev_msg.get_trait('mgcp', 'rtp_port') == rtp_port
		crcx_ok = None
		for prev_msg in find_recent_msg(msg, messages, my_idx, cond):
			for c in (prev_msg.src_conns + prev_msg.dst_conns):
				rtp_conn.merge_subscr_conns(c)


class Layer_gsm_abis_rsl(Layer):
	def __init__(s, msg:Message):
		p = msg.p
		msgtype = sane_msgtype(p.get('gsm_abis_rsl.msg_type.showname'))
		msgtype_nr = p.get('gsm_abis_rsl.msg_type')
		msgtype_nr = str_to_int(msgtype_nr)

		ch = None
		ch_imm_ass = None

		# For Immediate Assignment, the assigned TS/chan is more interesting
		ts = p.get('gsm_a_ccch.gsm_a_rr_timeslot')
		cbits = (p.get('gsm_a_ccch.gsm_a_rr_sdcch4_sdcchc4_cbch')
			or p.get('gsm_a_ccch.gsm_a_rr_sdcch8_sdcchc8_cbch'))
		try:
			ch_ts = int(ts)
			ch_cbits = int(cbits)
			ch_imm_ass = f'{ch_ts}-{ch_cbits}'
		except:
			pass

		# normal RSL messages on a given TS/chan
		ts = p.get('gsm_abis_rsl.ch_no_tn')
		cbits = p.get('gsm_abis_rsl.ch_no_cbits')
		if ts is not None and cbits is not None:
			try:
				ch_ts = int(ts)
				ch_cbits = int(cbits)
				ch = f'{ch_ts}-{ch_cbits}'
			except:
				raise

		ch_assign = None
		new_ch_ts = p.get('gsm_a_dtap.gsm_a_rr_timeslot')
		new_ch_ss = p.get('gsm_a_dtap.gsm_a_rr_tch_facch_sacchf')
		if new_ch_ts and new_ch_ss:
			ch_assign = f'{new_ch_ts}-{new_ch_ss}'

		rtp_local_port = None
		ipacc_rtp_local_ip = p.get('gsm_abis_rsl.ipacc_local_ip')
		ipacc_rtp_local_port = p.get('gsm_abis_rsl.ipacc_local_port')
		if ipacc_rtp_local_ip and ipacc_rtp_local_port:
			rtp_local_port = IpPort.get(ipacc_rtp_local_ip, ipacc_rtp_local_port)

		rtp_remote_port = None
		ipacc_rtp_remote_ip = p.get('gsm_abis_rsl.ipacc_remote_ip')
		ipacc_rtp_remote_port = p.get('gsm_abis_rsl.ipacc_remote_port')
		if ipacc_rtp_remote_ip and ipacc_rtp_remote_port:
			rtp_remote_port = IpPort.get(ipacc_rtp_remote_ip, ipacc_rtp_remote_port)

		req_ref_l = (p.get('gsm_abis_rsl.req_ref_ra'),
				p.get('gsm_abis_rsl.req_ref_t1prim'),
				p.get('gsm_abis_rsl.req_ref_t2'),
				p.get('gsm_abis_rsl.req_ref_t3'))
		if not all(req_ref_l):
			req_ref_l = (p.get('gsm_a_ccch.gsm_a_rr_ra'),
				p.get('gsm_a_ccch.gsm_a_rr_t1prim'),
				p.get('gsm_a_ccch.gsm_a_rr_t2'),
				p.get('gsm_a_ccch.gsm_a_rr_t3'))
		req_ref = None
		if all(req_ref_l):
			req_ref = '-'.join(req_ref_l)

		try:
			page_tmsi = tmsi_standardize(msg.p.cap_p.gsm_abis_rsl._all_fields['3gpp.tmsi'])
		except:
			page_tmsi = None

		traits = Traits(
			msgtype_nr=msgtype_nr,
			ch=ch,
			ch_imm_ass=ch_imm_ass,
			ch_assign=ch_assign,
			chan_type=p.get('gsm_abis_rsl.ch_type'),
			rtp_port=rtp_local_port,
			rtp_remote_port=rtp_remote_port,
			tmsi=tmsi_standardize(p.get('gsm_abis_rsl.gsm_a_tmsi')),
			imsi=p.get('gsm_abis_rsl.gsm_a_imsi'),
			page_tmsi=page_tmsi,
			arfcn = p.get('gsm_a_dtap.gsm_a_rr_single_channel_arfcn') or p.get('gsm_abis_rsl.gsm_a_rr_single_channel_arfcn'),
			req_ref = req_ref,
			)

		super().__init__(msg=msg, proto='rsl', msgtype=msgtype, traits=traits, cap_p_name='gsm_abis_rsl')
		# ignore CCCH Load INDication
		#if msgtype_nr == 18:
		#	msg.hide = True

	def identify_entities(s, msg:Message, messages, my_idx):
		ids = []
		msgtype = msg.get_trait('rsl', 'msgtype')

		if msgtype in ('RF-RESource-INDication', 'CCCH-LOAD-INDication', 'CHANnel-ReQuireD', ):
			# INDication from BTS to BSC
			ids.append(Message.EntityIdent(proto='rsl', src_kind='BTS', dst_kind='BSC'))
		if msgtype in ('CHANnel-ACTIVation', 'IMMEDIATE-ASSIGN-COMMAND'):
			# from BSC to BTS
			ids.append(Message.EntityIdent(proto='rsl', dst_kind='BTS', src_kind='BSC'))

		rtp_port = msg.get_trait('rsl', 'rtp_port')
		if rtp_port and msg.src_entity_is('BTS') and msgtype in (
				'ip.access-CRCX-ACK', 'ip.access-MDCX-ACK'):
			ids.append(Message.EntityIdent(proto='rtp', src_kind='BTS', src_entity=msg.src.entity, src_port=rtp_port))

		if msgtype == 'ip.access-MDCX':
			# This ip.a MDCX's rtp_remote_port should match an earlier MGCP CRCX-OK message, and we now
			# know that this BSC asked for it.

			rtp_port = msg.get_trait('rsl', 'rtp_remote_port')
			if not rtp_port:
				return None

			def cond(prev_msg):
				return prev_msg.get_trait('mgcp', 'rtp_port') == rtp_port
			crcx_ok = None
			for prev_msg in find_recent_msg(msg, messages, my_idx, cond):
				crcx_ok = prev_msg
				break
			if not crcx_ok:
				return None
			bsc = msg.src.entity
			mgw = crcx_ok.src.entity
			ids.append( Message.EntityIdent(proto='mgcp', src_port=crcx_ok.src, src_entity=mgw, src_kind='MGW@BSC', rename=True,
					dst_port=crcx_ok.dst, dst_entity=bsc, dst_kind='BSC') )

		return ids

	def collapse(s, messages, my_idx):
		# combine duplicates like rsl.CCCH-LOAD-INDication
		for i in reversed(range(my_idx)):
			prev_msg = messages[i]
			if not prev_msg:
				continue
			if prev_msg.finalized:
				break
			# stop combining at any non-rsl (and non-minor) message
			if not 'rsl' in prev_msg.layers:
				if all(l.minor for l in prev_msg.layers.values()):
					continue
				else:
					break
			if not same_nonempty(prev_msg.get_traits('rsl'), s.msg.get_traits('rsl')):
				continue
			if s.msg.same_src_dst(prev_msg, forward=True):
				# found a recent similar packet, combine
				prev_msg.count += 1
				messages[my_idx] = None
				prev_msg.absorb_msg(s.msg)
				return prev_msg
		return s.msg

	@classmethod
	def identify_conns_ra(cls, messages:list, my_idx:int):
		msg = messages[my_idx]

		msgtype = msg.get_trait('rsl', 'msgtype')

		bts = msg.entity('BTS')
		if bts is None:
			return None
		bts_port = msg.get_port('BTS')
		if bts_port is None:
			return None
		ra = msg.get_trait('rsl', 'req_ref')
		if ra is None:
			return None
		bts_ra = f'{bts_port.entity.label()}.ra{ra}'

		proto = 'rsl'
		conn_id = bts_ra

		conn = None

		if msgtype == 'CHANnel-ReQuireD':
			if not msg.src_entity_is('BTS'):
				return
			bts = msg.src.entity
			bts_port = msg.src
			bsc = msg.dst.entity
			bsc_port = msg.dst
			conn = Conn.open(proto, bts_port, conn_id, msg, entity=bts)
			Conn.open(proto, bsc_port, conn_id, msg, entity=bsc, counterparts=[conn])

		elif msgtype in ('CHANnel-ACTIVation'):
			conn = Conn.message(proto, msg.dst, conn_id, msg)

		elif msgtype == 'IMMEDIATE-ASSIGN-COMMAND':
			# the RA token has fulfilled its use as soon as an IMM ASS happened
			Conn.close(proto, msg.dst, conn_id, msg)

		else:
			Conn.message(proto, msg.dst, conn_id, msg)

		if conn:
			for c in (msg.src_conns + msg.dst_conns):
				conn.merge_subscr_conns(c)

	@classmethod
	def identify_conns_ch(cls, messages:list, my_idx:int):
		msg = messages[my_idx]
		proto = 'rsl'
		msgtype = msg.get_trait('rsl', 'msgtype')

		# For Immediate Assignment, the assigned TS/chan is the one to match on
		if msgtype == 'IMMEDIATE-ASSIGN-COMMAND':
			ch = msg.get_trait('rsl', 'ch_imm_ass')
		else:
			ch = msg.get_trait('rsl', 'ch')

		if ch is None:
			return None

		if msgtype in ('CHANnel-ACTIVation') or msg.src_entity_is('BSC'):
			bsc = msg.src.entity
			bsc_port = msg.src
			bts = msg.dst.entity
			bts_port = msg.dst
		elif msg.src_entity_is('BTS'):
			bts = msg.src.entity
			bts_port = msg.src
			bsc = msg.dst.entity
			bsc_port = msg.dst
		else:
			return None

		if bts_port.entity is None:
			return None

		bts_ch = f'{bts_port.entity.label()}.ch{ch}'
		conn_id = bts_ch

		if msgtype == 'CHANnel-ACTIVation':
			conn = Conn.open(proto, bts_port, conn_id, msg, entity=bts)
			Conn.open(proto, bsc_port, conn_id, msg, entity=bsc, counterparts=[conn])
		elif msgtype == 'RF-CHANnel-RELease-ACKnowledge':
			conn = Conn.close(proto, msg.src, conn_id, msg)
		else:
			conn = Conn.message(proto, bts_port, conn_id, msg)
		if conn:
			for c in (msg.src_conns + msg.dst_conns):
				conn.merge_subscr_conns(c)

		# when changing to a new ch, e.g. a regular Assignment Command to change from SDCCH to TCH,
		# associate the new channel with the conn
		ch_assign = msg.get_trait('rsl', 'ch_assign')
		if ch_assign:
			conn_id = f'{bts_port.entity.label()}.ch{ch_assign}'
			conn = Conn.find(proto, bts_port, conn_id)
			if conn:
				conn.add_message(msg)
				for c in (msg.src_conns + msg.dst_conns):
					conn.merge_subscr_conns(c)


	@classmethod
	def identify_conns_rtp(cls, messages:list, my_idx:int):
		msg = messages[my_idx]
		# BTS RTP
		rtp_port = msg.get_trait('rsl', 'rtp_port')
		if rtp_port and msg.src_entity_is('BTS') and msg.get_trait('rsl','msgtype') == 'ip.access-CRCX-ACK':
			rtp_port.entity = msg.src.entity
			rtp_conn = Conn.open('rtp', rtp_port, conn_id=rtp_port.key(), start_msg=msg, add_message=False)
			for c in (msg.src_conns + msg.dst_conns):
				rtp_conn.merge_subscr_conns(c)

		# MGW@BSC RTP towards BTS
		rtp_port = msg.get_trait('rsl', 'rtp_remote_port')
		if rtp_port:
			rtp_conn = Conn.find('rtp', rtp_port, conn_id=rtp_port.key())
			if rtp_conn:
				rtp_conn.add_message(msg)
				for c in (msg.src_conns + msg.dst_conns):
					rtp_conn.merge_subscr_conns(c)

	@classmethod
	def identify_conns_paging(cls, messages:list, my_idx:int):
		msg = messages[my_idx]
		msgtype = msg.get_trait('rsl', 'msgtype')

		if msgtype != 'PAGING-CoMmanD':
			return

		tmsi = msg.get_trait('rsl', 'page_tmsi')
		if tmsi is None:
			return
		conn_id = f'page_tmsi{tmsi}'

		subscr = Subscriber.by_tmsi(tmsi)
		if subscr is None:
			return

		rsl_conn = Conn.open('rsl', msg.src, conn_id, msg)
		subscr_conn = SubscriberConn()
		subscr.add_subscriber_conn(subscr_conn)
		subscr_conn.add_conn(rsl_conn)

		# Paging does not have a proper end, it may never be answered.
		# A Conn wants to be closed at some point. Just close it directly.
		Conn.close_conn(rsl_conn, msg)

		# Expecting a recent Paging on BSSMAP
		bssmap_paging = None
		def cond(prev_msg):
			return (prev_msg.get_trait('bssmap', 'msgtype') == 'Paging'
				and prev_msg.get_trait('bssmap', 'tmsi') == tmsi)
		for match in find_recent_msg(msg, messages, my_idx, cond):
			bssmap_paging = match
			break

		if bssmap_paging is None:
			return

		bssmap_conn = Conn.find('bssmap', bssmap_paging.dst, conn_id, find_in_closed_conns=True)
		if bssmap_conn:
			rsl_conn.merge_subscr_conns(bssmap_conn)

	@classmethod
	def identify_conns(cls, messages:list, my_idx:int):
		cls.identify_conns_ra(messages, my_idx)
		cls.identify_conns_ch(messages, my_idx)
		cls.identify_conns_rtp(messages, my_idx)
		cls.identify_conns_paging(messages, my_idx)

class Layer_gsm_a_dtap(Layer):
	def __init__(s, msg:Message):
		dtap = msg.p.get('gsm_a_dtap')
		assert dtap is not None

		msgtype = None
		msgtype_nr = None
		for f in dtap._get_all_fields_with_alternates():
			if f.name.startswith('gsm_a.dtap.msg_') and f.name.endswith('_type'):
				msgtype = f.showname_value
				try:
					msgtype_nr = int(f.raw_value)
				except:
					pass
		traits = Traits(
			msgtype_nr=msgtype_nr,
			imsi=msg.p.get('gsm_a_dtap.e212_imsi') or msg.p.get('gsm_a_dtap.gsm_a_imsi'),
			tmsi=tmsi_standardize(msg.p.get('gsm_a_dtap.gsm_a_tmsi') or msg.p.get('gsm_a_dtap.3gpp_tmsi')),
			imei=msg.p.get('gsm_a_dtap.gsm_a_imei'),
			to_msisdn=msg.p.get('gsm_a_dtap.cld_party_bcd_num'),
			)
		super().__init__(msg=msg, proto='dtap', msgtype=msgtype, traits=traits, cap_p_name='gsm_a_dtap')


class Layer_gsup(Layer):
	def __init__(s, msg:Message):
		msgtype = sane_msgtype(msg.p.get('gsup.msg_type.showname'))
		msisdn = None
		if '-forwardSM-' not in msgtype:
			msisdn = msg.p.get('gsup.e164_msisdn')
		to_msisdn = msg.p.get('gsup.gsm_sms_tp_da')

		msgtype_nr = None
		is_request = None
		try:
			msgtype_nr = int(msg.p.get('gsup.msg_type'))
			is_request = not (msgtype_nr & 0x3)
		except:
			pass

		session_state = None
		try:
			session_state = int(msg.p.get('gsup.session_state'))
		except:
			pass

		traits = Traits(
			imsi=msg.p.get('gsup.e212_imsi'),
			msgtype_nr=msgtype_nr,
			is_request=is_request,
			cn_domain=sane_showname(msg.p.get('gsup.cn_domain.showname')),
			msisdn=msisdn,
			to_msisdn=to_msisdn,
			source_name=msg.p.get('gsup.source_name_text'),
			destination_name=msg.p.get('gsup.destination_name_text'),
			session_id=msg.p.get('gsup.session_id'),
			session_state=session_state,
			)
		super().__init__(msg=msg, proto='gsup', msgtype=msgtype, traits=traits)

	@classmethod
	def identify_conns(cls, messages:list, my_idx:int):
		msg = messages[my_idx]
		imsi = msg.get_trait('gsup', 'imsi')
		is_request = msg.get_trait('gsup', 'is_request')
		session_id = msg.get_trait('gsup', 'session_id')
		session_state = msg.get_trait('gsup', 'session_state')
		if not imsi:
			return
		proto = 'gsup'
		if session_id:
			conn_id = f'{imsi}:{session_id}'
			have = Conn.find(proto, msg.src, conn_id) or Conn.find(proto, msg.dst, conn_id)
			if have is None:
				have = Conn.open(proto, msg.src, conn_id, msg,
					  counterparts=[Conn.open(proto, msg.dst, conn_id, msg)])
			if session_state is not None and session_state == 0x3:
				Conn.close(proto, msg.src, conn_id, msg)
			else:
				have.add_message(msg)

		else:
			conn_id = f'{imsi}'

			if is_request:
				have = Conn.find(proto, msg.src, conn_id)
				if have is None:
					Conn.open(proto, msg.src, conn_id, msg)
				else:
					have.add_message(msg)
			else:
				have = Conn.find(proto, msg.dst, conn_id)
				if have is None:
					# it's a stray response? anyway create a conn for association with a subscriber
					Conn.open(proto, msg.dst, conn_id, msg)
				Conn.close(proto, msg.dst, conn_id, msg)

	def identify_entities(s, msg:Message, messages, my_idx):
		if msg.get_trait('gsup', 'msgtype') in ('SendAuthInfo-Request', 'UpdateLocation-Request', 'PurgeMS-Request'):
			cn = msg.get_trait('gsup', 'cn_domain')
			src_kind = None
			src_entity = None
			src_subscr_conn = None
			if msg.get_trait('gsup', 'source_name'):
				# proxy forwarding
				src_kind = 'HLR'
				traits = [name for proto, name, result in msg.get_traits('gsup') if name not in ('source_name', 'destination_name')]
				for match in find_same_trait(msg, messages, my_idx, 'gsup', traits):
					if not match.dst_entity_is('HLR'):
						continue
					src_entity = match.dst.entity
					break
			else:
				if cn == 'CS':
					src_kind = 'MSC'
				elif cn == 'PS':
					src_kind = 'SGSN'

				if src_kind:
					# associate MSC GSUP port with MSC BSSMAP port
					imsi = msg.get_trait('gsup', 'imsi')
					if imsi:
						subscr = Subscriber.by_imsi(imsi)
						def cond(prev_msg):
							return (prev_msg.dst_entity_is(src_kind)
								and prev_msg.is_subscriber_related(subscr))
						for match in find_recent_msg(msg, messages, my_idx, cond):
							src_entity = match.dst.entity
							break

					# i forgot whatever this does:
					if not src_entity:
						src_entity, src_subscr_conn = s.msg.find_entity(src_kind,
												with_port=('bssgp', 'IuPS'))
				else:
					# no cn_domain in the GSUP message, try to guess
					msc, msc_subscr_conn = s.msg.find_entity('MSC')
					sgsn, sgsn_subscr_conn = s.msg.find_entity('SGSN')
					if msc and not sgsn:
						src_entity = msc
						src_subscr_conn = msc_subscr_conn
					if sgsn and not msc:
						src_entity = sgsn
						src_subscr_conn = sgsn_subscr_conn

			if src_subscr_conn is not None and msg.src_conns:
				for c in msg.src_conns:
					c.subscriber_conn = SubscriberConn.merge(c.subscriber_conn, src_subscr_conn)

			return Message.EntityIdent(proto='gsup', src_kind=src_kind, dst_kind='HLR', src_entity=src_entity, dst_entity=msg.dst.entity)

class Layer_sip(Layer):
	def __init__(s, msg:Message):
		method = msg.p.get('sip.method')
		cseq_method = msg.p.get('sip.cseq_method')
		status_code = msg.p.get('sip.status_code')
		status_line = msg.p.get('sip.status_line')
		if status_line:
			if '--' in status_line:
				status_line = status_line[:status_line.index('--')]
			status_line = status_line.strip()
			status = status_line.split()[-1]
		else:
			status = status_code
		if status:
			msgtype = f'{cseq_method}-{status}'
		elif method:
			msgtype = method
		else:
			msgtype = cseq_method

		sip_from_host = msg.p.get('sip.from_host')
		sip_from_port = msg.p.get('sip.from_port')
		sip_from = IpPort.get(sip_from_host, sip_from_port)

		rtp_port = None
		ip = msg.p.get('sip.sdp_connection_info_address')
		port = msg.p.get('sip.sdp_media_port')
		if ip and port:
			rtp_port = IpPort.get(ip, port)

		server = msg.p.get('sip.Server')
		agent = msg.p.get('sip.User-Agent')

		traits = Traits(
			sip_agent=server or agent,
			sip_from=sip_from,
			call_id = msg.p.get('sip.call_id'),
			method = cseq_method,
			seq = msg.p.get('sip.cseq_seq'),
			to_msisdn = msg.p.get('sip.to_user'),
			from_msisdn = msg.p.get('sip.from_user'),
			from_tag = msg.p.get('sip.from_tag'),
			r_uri = msg.p.get('sip.r_uri'),
			status_code = status_code,
			rtp_port=rtp_port,
			)
		super().__init__(msg=msg, proto='sip', msgtype=msgtype, traits=traits)

	def identify_entities(s, msg:Message, messages, my_idx):
		src_kind = 'SIP'
		sip_from = msg.get_trait('sip', 'sip_from')
		agent = msg.get_trait('sip', 'sip_agent')

		rename = False
		if agent and sip_from and sip_from == msg.src:
			rename = 'src'
			if agent.startswith('kamailio'):
				src_kind = 'PBX'
			elif agent.startswith('sofia'):
				src_kind = 'SIPCON'
			else:
				rename = False

		return Message.EntityIdent(proto='sip', src_kind=src_kind, dst_kind='SIP', rename=rename)

	@classmethod
	def identify_conns(cls, messages:list, my_idx:int):
		msg = messages[my_idx]

		msgtype = msg.get_trait('sip', 'msgtype')
		call_id = msg.get_trait('sip', 'call_id')
		sip_from = msg.get_trait('sip', 'sip_from')

		if msgtype in ('INVITE','INVITE-OK') and sip_from and sip_from == msg.src:
			conn = Conn.open('sip', msg.src, call_id, start_msg=msg)
			rtp_port = msg.get_trait('sip', 'rtp_port')
			if rtp_port is None:
				return

			rtp_conn = Conn.find('rtp', rtp_port, conn_id=rtp_port.key())
			if rtp_conn is None:
				return
			if not conn.subscriber_conn:
				conn.merge_subscr_conns(rtp_conn)
		else:
			conn = Conn.message('sip', msg.src, call_id, msg)

		if conn is None:
			return


class Layer_gsmtap_log(Layer):
	def __init__(s, msg:Message):
		app = msg.p.get('gsmtap_log.ident')
		level = msg.p.get('gsmtap_log.level')
		level_str = sane_showname(msg.p.get('gsmtap_log.level.showname'))
		logmsg = msg.p.get('gsmtap_log.string')
		cat = msg.p.get('gsmtap_log.subsys')

		if level_str != 'ERROR':
			return

		return

		msgtype = f'{app}.{level_str}'
		msg.log(Color.colored('red', logmsg))

		traits = Traits(
			msgtype=msgtype,
			level=level,
			app=app,
			cat=cat,
			logmsg=logmsg,
			)
		super().__init__(msg=msg, proto='log', msgtype=msgtype, traits=traits)

	def identify_entities(s, msg:Message, messages, my_idx):
		app = msg.get_trait('log', 'app')
		if app.startswith('Osmo'):
			app = app[4:]
		return Message.EntityIdent(proto='log', src_kind=app, dst_kind='LOG')


class MessageFilter:
	def __init__(s, layer=None, idx=None, values=[], negate=False):
		set_instance_vars_from_args()

	def matches(s, msg:Message):
		r = s._matches(msg)
		if s.negate:
			return not r
		return r

	def _matches(s, msg:Message):
		if s.layer and s.layer not in msg.layers:
			return False
		if s.idx and not (msg.p.idx == s.idx or any(a.p.idx == s.idx for a in msg.absorbed)):
			return False
		if s.values:
			layers = s.layer or msg.layers.keys()
			for k,v in s.values:
				for proto, name, result in msg.get_traits(layers, k):
					if v is None and name == k:
						return True
					if result is None or result == v:
						return True
			p_layers = None
			if s.layer:
				msg_layer = msg.layers.get(s.layer)
				if msg_layer:
					p_layers = [msg_layer.cap_p_name]
				else:
					p_layers = [s.layer]
			else:
				p_layers = [layer.cap_p_name for layer in msg.layers.values()]
			for k,v in s.values:
				for p_layer in p_layers:
					p_val = msg.p.get(p_layer + '.' + k)
					if p_val is None:
						continue
					if v is None:
						return True
					if v == str(p_val):
						return True
			return False
		return True

	@classmethod
	def debug(cls, flt_list, msg:Message):
		layers = set()
		for flt in flt_list:
			if flt.negate:
				continue
			if flt.layer is None:
				layers.update(msg.layers.keys())
			else:
				layers.add(flt.layer)
		for layer_name, layer in msg.layers.items():
			if layer_name not in layers:
				continue
			LOG(dir_p(msg.p, layer.cap_p_name))

	def __repr__(s):
		t = []
		if s.negate:
			t.append('NOT')
		if s.layer:
			t.append(f'layer {s.layer!r}')
		if s.idx:
			t.append(f'packet nr {s.idx}')
		if s.values:
			t_v = [(f'{k} == {v!r}' if v is not None else f'has {k}') for k,v in s.values]
			t.append('values: ' + (' or '.join(t_v)))
		return ', '.join(t)

	word_re = re.compile('^[a-zA-Z0-9_=-]*')
	@classmethod
	def parse(cls, spec_str):
		if spec_str is None:
			return []
		if not spec_str:
			return [MessageFilter()]
		filters = []
		token = None
		try:
			for token in spec_str.split(','):
				negate = False
				if token.startswith('!'):
					token = token[1:]
					negate = True
				layer = cls.word_re.match(token).group()
				flt = MessageFilter(layer=layer, negate=negate)
				rest = cls.word_re.split(token)[1]
				while rest:
					char = rest[0]
					rest = rest[1:]
					word = cls.word_re.match(rest).group()
					rest = cls.word_re.split(rest)[1]
					if char == '#':
						flt.idx = int(word)
					elif char == '.':
						if not flt.values:
							flt.values = []
						if '=' in word:
							name = word[:word.index('=')]
							val = word[word.index('=')+1:]
							flt.values.append((name, val))
						else:
							flt.values.append((word, None))
					else:
						raise Exception('Unknown token: %r' % (char + word))
				filters.append(flt)
			return filters
		except:
			out_error('Some mistake in message filter: %r in token %r' % (spec_str, token))
			raise

	@classmethod
	def match(cls, flt_list, msg):
		any_match = False
		for flt in flt_list:
			r = flt.matches(msg)
			if flt.negate and not r:
				return False
			any_match = any_match or r
		return any_match


	DOC = '''messagefilter examples, for --filter-msg and --debug:
	dtap
		All messages that contain a DTAP layer.
	dtap.msgtype=Identity-Request
		All DTAP msgtype=Identity-Request messages; for debug, show
		dtap layer.
	.msgtype=Identity-Request
		All msgtype=Identity-Request messages; for debug, show all
		layers. (Value names can be either parsed traits or raw packet
		names.)
	sccp.src_lref=0x00010000.dst_lref=0x00010000
		All messages with an SCCP layer and either src_lref or dst_lref
		== 0x00010000.
	.imsi
		All messages where any layer contains a value named 'imsi'.
	'#123'
		Message number 123 (don't forget to quote for the shell).
	'gsup,#614,sccp.src_lref=0x00010000'
		Show all GSUP messages, packet number 614 and all SCCP with
		given source local reference.
	'!rsl.msgtype=CCCH-LOAD-INDication'
		Don't show CCCH-LOAD-INDication message types (quote for the
		shell).
	'''

class UI:
	def __init__(s, opts, finalize_after_seconds=5):
		set_instance_vars_from_args()

		s.messages = []
		s.finalized_idx = -1

		s.show_traits = None
		if s.opts.show_traits:
			if s.opts.show_traits == 'all':
				s.show_traits = True
			else:
				s.show_traits = s.opts.show_traits.split(',')
		s.show_conns = None
		if s.opts.show_conns:
			if s.opts.show_conns == 'all':
				s.show_conns = True
			else:
				s.show_conns = s.opts.show_conns.split(',')
		s.filter_msg = MessageFilter.parse(s.opts.filter_msg)
		for flt in s.filter_msg:
			out_text_now('Filter-msg:', flt)
		s.debug = MessageFilter.parse(s.opts.debug)
		for dbg in s.debug:
			out_text_now('Debug:', dbg)

		s.filter_subscr = []
		if s.opts.filter_subscr:
			tokens = s.opts.filter_subscr.split(',')
			names = ('imsi', '0x', 'imei', 'msisdn', 'tmsi')
			for token in tokens:
				handled = False
				for name in names:
					if token.startswith(name):
						token_val = token[len(name):]
						if not token_val.isdigit():
							continue
						s.filter_subscr.append(name + token[len(name):])
						handled = True
						break
				if not handled:
					s.filter_subscr.append(token)
					s.filter_subscr.extend([name + token for name in names])

	def out_text_now(s, *args, **kwargs):
		'to be implemented by child class'
		assert False

	def out_error(s, *args, **kwargs):
		'to be implemented by child class'
		assert False

	def msg_finalized(s, msg, apply_filter=True):
		'to be implemented by child class'
		assert False

	def flush_msg(s, msg):
		msg.finalized = True
		s.msg_finalized(msg)

	def msg_filter(s, msg):
		'''Return True when the message passes active message filtering, False if it should be hidden'''
		if s.filter_msg and not MessageFilter.match(s.filter_msg, msg):
			return False
		if all(l.minor for l in msg.layers.values()):
			return False
		if msg.hide:
			return False
		if s.filter_subscr:
			match = False
			match_vals = set()
			for subscr in msg.related_subscribers():
				match_vals.update((f'imsi{subscr.imsi}', f'imei{subscr.imei}', f'msisdn{subscr.msisdn}'))
				match_vals.update(subscr.tmsis)
				match_vals.update(f'tmsi{tmsi[2:]}' for tmsi in subscr.tmsis)
				match_vals.update(f'tmsi{tmsi}' for tmsi in subscr.tmsis)

			if not any(token in match_vals for token in s.filter_subscr):
				return False
		return True

	def flush(s, timestamp_now=0, finalize_after_seconds=0):
		flush_t = timestamp_now - finalize_after_seconds
		for i in range(s.finalized_idx+1, len(s.messages)):
			msg = s.messages[i]
			if not msg:
				continue
			if timestamp_now and msg.timestamp > flush_t:
				break
			s.finalized_idx = i
			s.flush_msg(msg)

	def start(s):
		pass

	def stop(s):
		pass

	def add_msg(s, msg):
		global g_current_msg
		s.flush(msg.timestamp, s.finalize_after_seconds)
		try:
			if s.debug and any(dbg_filter.matches(msg) for dbg_filter in s.debug):
				msg.debug = True
			g_current_msg = msg
			if not msg.layers:
				return
			s.messages.append(msg)
			idx = len(s.messages) - 1
			changed_msg = msg.collapse(s.messages, idx)
			# if the received message was absorbed by another, continue to identify the modified message using the
			# new index
			if changed_msg is not None and changed_msg is not msg:
				msg = changed_msg
				idx = s.messages.index(msg)
			msg.identify_entities(s.messages, idx)
			msg.identify_conns(s.messages, idx)
			Subscriber.identify_subscriber(msg)

		except:
			s.flush()

			out_error('Exception')
			raise

	def process_messages(s, msg_src):
		for msg in msg_src.next():
			if 0 and msg.p.idx in (3676,):
				msg.log('rsl all_fields ', msg.p.cap_p.gsm_abis_rsl._all_fields)
				msg.log(msg.p.all_str('gsm_abis_rsl'))

			s.add_msg(msg)
		s.flush()
		msg_src.done()

class UI_Plain(UI):
	def out_text_now(s, *args, **kwargs):
		print(to_text(*args, **kwargs))

	def out_error(s, *args, **kwargs):
		s.out_text_now(Color.colored('red', '*** ERROR:'), *args, **kwargs)
		if g_current_msg:
			s.out_text_now(Color.colored('red', '*** ERROR: while processing msg'), g_current_msg.str(show_traits=True, show_conns=True))
		s.out_text_now(trace())

	def msg_print(s, msg, apply_filter=True):
		if apply_filter and not s.msg_filter(msg):
			return
		s.out_text_now(msg.str(ladder=True, one_column_per_kind=True, show_traits=s.show_traits, show_conns=s.show_conns))
		if s.debug and MessageFilter.match(s.debug, msg):
			MessageFilter.debug(s.debug, msg)

	def msg_finalized(s, msg):
		s.msg_print(msg, apply_filter=True)

class UI_Quiet(UI_Plain):
	def msg_finalized(s, msg):
		pass

class UI_Curses(UI):
	pass

class MsgSource:
	def __init__(s, opts):
		set_instance_vars_from_args()
		s.start_t = None
		s.p_min_t = None
		s.p_max_t = None
		s.end_t = None

	def _next_cap_p(s):
		assert False

	def next(s) -> Message:
		p_idx = 0
		s.start_t = time.time()
		warn_t = s.start_t
		warn_p_t = None
		for cap_p in s._next_cap_p():
			p_idx += 1
			if p_idx < s.opts.packet_start:
				continue
			if s.opts.packet_count and (p_idx - s.opts.packet_start) > s.opts.packet_count:
				break
			if s.opts.packet_end and p_idx > s.opts.packet_end:
				break
			msg = Message.parse(Packet(p_idx, cap_p))
			if msg is None or not msg.layers:
				continue
			s.p_min_t = msg.timestamp if s.p_min_t is None else min(s.p_min_t, msg.timestamp)
			s.p_max_t = msg.timestamp if s.p_max_t is None else max(s.p_max_t, msg.timestamp)

			now = time.time()
			if warn_p_t is None or now > warn_t + 3:
				if warn_p_t:
					packet_time = s.p_max_t - warn_p_t
					real_time = now - warn_t
					if real_time > (1.3 * packet_time):
						out_text_now(f'! taking longer to calculate than packets arrive by {100.*(real_time - packet_time)/packet_time:.1f}%')
				warn_t = now
				warn_p_t = s.p_max_t

			yield msg

	def done(s):
		if s.start_t is None or s.p_min_t is None:
			out_text_now('Nothing processed.')
		s.end_t = time.time()
		out_text_now(f'packet time: {s.p_max_t - s.p_min_t:.1f}s  in real time: {s.end_t - s.start_t:.1f}s')

class MsgSource_File(MsgSource):
	def __init__(s, path, opts):
		set_instance_vars_from_args()
		super().__init__(opts)

	def _next_cap_p(s):
		for cap_p in pyshark.FileCapture(s.path):
			yield cap_p

class MsgSource_Live(MsgSource):
	def __init__(s, iface, opts):
		set_instance_vars_from_args()
		super().__init__(opts)

	def _next_cap_p(s):
		for cap_p in pyshark.LiveCapture(s.iface).sniff_continuously():
			yield cap_p

class MsgSource_Pipe(MsgSource):
	def __init__(s, opts):
		super().__init__(opts)

	def _next_cap_p(s):
		from pyshark.capture.pipe_capture import PipeCapture
		for cap_p in PipeCapture(sys.stdin):
			yield cap_p

def run_tests():
	def out_test(*args, **kwargs):
		print(*args, **kwargs)

	d = dddict()
	d.sset(('a', 'b', 'c'), 'abc')
	d.sset(('a', 'b', 'd'), 'abd')
	out_test(d)
	assert d == {'a': {'b': {'c': 'abc', 'd': 'abd'}}}
	def verify_gget(keys, expect):
		val = d.gget(keys)
		out_test('gget:', keys,'=',val)
		assert val == expect
	verify_gget(('a', 'b', 'c'), 'abc')
	verify_gget(('a', 'b', 'd'), 'abd')
	verify_gget(('a', 'b', 'x'), None)
	verify_gget(('a', 'b'), {'c': 'abc', 'd': 'abd'})
	verify_gget(('a',), {'b': {'c': 'abc', 'd': 'abd'}})
	verify_gget(('x',), None)
	def verify_ppop(keys, expect):
		try:
			val = d.ppop(keys)
			assert expect is not None
		except KeyError:
			assert expect is None
			out_test('ppop:', keys,'=',None)
			return
		out_test('ppop:', keys,'=',val)
		assert val == expect
		assert d.gget(keys) is None
	verify_ppop(('a', 'b', 'c'), 'abc')
	verify_ppop(('a', 'b', 'd'), 'abd')
	verify_ppop(('a', 'b', 'x'), None)
	d.sset(('a', 'b', 'c'), 'abc')
	d.sset(('a', 'b', 'd'), 'abd')
	verify_ppop(('a', 'b'), {'c': 'abc', 'd': 'abd'})
	d.sset(('a', 'b', 'c'), 'abc')
	d.sset(('a', 'b', 'd'), 'abd')
	verify_ppop(('a',), {'b': {'c': 'abc', 'd': 'abd'}})
	verify_ppop(('x',), None)

SUBSCRIBERFILTER_DOC = '''subscriberfilter examples, for --filter-subscr:
	123
		Show subscriber where any value matches 123 (probably only MSISDN will
		match, because '123' is too short for IMSI etc).
	imsi123456789012345
	imei123456789012345
	msisdn123456789012345
	tmsi1234abcd
		Show subscriber with the given IMSI/IMEI/MSISDN/TMSI.
	imsi123456,imsi987654
		Show both these IMSIs.
	imsi123456,msisdn123,1234abcd,imei987654
		Show all of these subscribers: IMSI 123456, MSISDN 123, TMSI 0x1234abcd
		and IMEI 987654.
'''
def parse_args():
	import argparse
	parser = argparse.ArgumentParser(description=__doc__
		+ '\n' + SUBSCRIBERFILTER_DOC
		+'\n' + MessageFilter.DOC,
			formatter_class=argparse.RawDescriptionHelpFormatter)
	parser.add_argument('--pcap-file', '-f', metavar='file')
	parser.add_argument('--live-capture', '-l', metavar='interface')
	parser.add_argument('--stdin-capture', '-i', action='store_true')
	parser.add_argument('--packet-start', '-S', default=0, type=int)
	parser.add_argument('--packet-count', '-C', default=0, type=int)
	parser.add_argument('--packet-end', '-E', default=0, type=int)
	parser.add_argument('--ui', '-u', metavar='USER-INTERFACE',
		help='How to display messages: plain / p = print to stdout as plain-text;'
		' curses / c = interactive curses interface; none / n = quiet',
		default='plain')
	parser.add_argument('--filter-subscr', default=None,
		help='Show only messages related to the given subscriberfilter')
	parser.add_argument('--filter-msg', default=None, metavar='messagefilter',
		help='Show only messages matching this messagefilter')
	parser.add_argument('--show-traits', default=None)
	parser.add_argument('--show-conns', default=None, help="'all' for all, or specific conn names (comma separated)")
	parser.add_argument('--collapse-stp', '-s', default=None, help="BSSAP via STP may appear duplicated. '-s1' collapses the duplicates, -s0 does not.")
	parser.add_argument('--test', action='store_true')
	parser.add_argument('--debug', metavar='messagefilter',
		help='Show a lot more info on messages matching this messagefilter')
	return parser.parse_args()

def main():
	opts = parse_args()

	if opts.test:
		run_tests()
	else:
		if (opts.collapse_stp or '').upper() in ['1', 'Y', 'YES', 'TRUE']:
			SCCP_COLLAPSE_STP = True
		if (opts.collapse_stp or '').upper() in ['0', 'N', 'NO', 'FALSE']:
			SCCP_COLLAPSE_STP = False
		ui_class = None
		ui_type = opts.ui or 'none'
		if 'plain'.startswith(ui_type):
			ui_class = UI_Plain
		elif 'curses'.startswith(ui_type):
			ui_class = UI_Curses
		elif 'none'.startswith(ui_type):
			ui_class = UI_Quiet
		else:
			ERR('Unknown UI type:', repr(ui_type))
			return 1
		g_ui = ui_class(opts)
		msg_source = None
		if opts.pcap_file:
			msg_source = MsgSource_File(opts.pcap_file, opts)
		elif opts.live_capture:
			msg_source = MsgSource_Live(opts.live_capture, opts)
		elif opts.stdin_capture:
			msg_source = MsgSource_Pipe(opts)
		else:
			ERR('No message source, try `-l any` or `-f my.pcap`')
			return 1
		g_ui.process_messages(msg_source)
		g_ui.flush()
		if Conn.open_conns:
			print('still open conns:', repr(Conn.open_conns))
	return 0

if __name__ == '__main__':
	if False:
		import cProfile
		cProfile.run('main()', sort='tottime')
	else:
		exit(main())
# vim: noexpandtab tabstop=8 shiftwidth=8