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Diffstat (limited to 'node-admin/scripts/pyroute2/netlink/__init__.py')
| -rw-r--r-- | node-admin/scripts/pyroute2/netlink/__init__.py | 1349 |
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diff --git a/node-admin/scripts/pyroute2/netlink/__init__.py b/node-admin/scripts/pyroute2/netlink/__init__.py deleted file mode 100644 index 499c7ab79d3..00000000000 --- a/node-admin/scripts/pyroute2/netlink/__init__.py +++ /dev/null @@ -1,1349 +0,0 @@ -# By Peter V. Saveliev https://pypi.python.org/pypi/pyroute2. Dual licensed under the Apache 2 and GPLv2+ see https://github.com/svinota/pyroute2 for License details. -''' -Netlink basics -============== - -General netlink packet structure:: - - nlmsg packet: - + header - + data - -Generic netlink message header:: - - nlmsg header: - + uint32 length - + uint16 type - + uint16 flags - + uint32 sequence number - + uint32 pid - -The `length` field is the length of all the packet, including -data and header. The `type` field is used to distinguish different -message types, commands etc. Please note, that there is no -explicit protocol field -- you choose a netlink protocol, when -you create a socket. - -The `sequence number` is very important. Netlink is an asynchronous -protocol -- it means, that the packet order doesn't matter and is -not guaranteed. But responses to a request are always marked with -the same sequence number, so you can treat it as a cookie. - -Please keep in mind, that a netlink request can initiate a -cascade of events, and netlink messages from these events can -carry sequence number == 0. E.g., it is so when you remove a -primary IP addr from an interface, when `promote_secondaries` -sysctl is set. - -Beside of incapsulated headers and other protocol-specific data, -netlink messages can carry NLA (netlink attributes). NLA -structure is as follows:: - - NLA header: - + uint16 length - + uint16 type - NLA data: - + data-specific struct - # optional: - + NLA - + NLA - + ... - -So, NLA structures can be nested, forming a tree. - -Complete structure of a netlink packet:: - - nlmsg header: - + uint32 length - + uint16 type - + uint16 flags - + uint32 sequence number - + uint32 pid - [ optional protocol-specific data ] - [ optional NLA tree ] - -More information about netlink protocol you can find in -the man pages. - -Pyroute2 and netlink -==================== - -packets -------- - -To simplify the development, pyroute2 provides an easy way to -describe packet structure. As an example, you can take the -ifaddrmsg description -- `pyroute2/netlink/rtnl/ifaddrmsg.py`. - -To describe a packet, you need to inherit from `nlmsg` class:: - - from pyroute2.netlink import nlmsg - - class foo_msg(nlmsg): - fields = ( ... ) - nla_map = ( ... ) - -NLA are described in the same way, but the parent class should be -`nla`, instead of `nlmsg`. And yes, it is important to use the -proper parent class -- it affects the header structure. - -fields attribute ----------------- - -The `fields` attribute describes the structure of the -protocol-specific data. It is a tuple of tuples, where each -member contains a field name and its data format. - -Field data format should be specified as for Python `struct` -module. E.g., ifaddrmsg structure:: - - ifaddrmsg structure: - + unsigned char ifa_family - + unsigned char ifa_prefixlen - + unsigned char ifa_flags - + unsigned char ifa_scope - + int ifa_index - -should be described as follows:: - - class ifaddrmsg(nlmsg): - fields = (('family', 'B'), - ('prefixlen', 'B'), - ('flags', 'B'), - ('scope', 'B'), - ('index', 'I')) - -Format strings are passed directly to the `struct` module, -so you can use all the notations like `>I`, `16s` etc. All -fields are parsed from the stream separately, so if you -want to explicitly fix alignemt, as if it were C struct, -use the `pack` attribute:: - - class tstats(nla): - pack = 'struct' - fields = (('version', 'H'), - ('ac_exitcode', 'I'), - ('ac_flag', 'B'), - ...) - -Explicit padding bytes also can be used, when struct -packing doesn't work well:: - - class ipq_mode_msg(nlmsg): - pack = 'struct' - fields = (('value', 'B'), - ('__pad', '7x'), - ('range', 'I'), - ('__pad', '12x')) - - -nla_map attribute ------------------ - -The `nla_map` attribute is a tuple of NLA descriptions. Each -description is also a tuple in two different forms: either -two fields, name and format, or three fields: type, name and -format. - -Please notice, that the format field is a string name of -corresponding NLA class:: - - class ifaddrmsg(nlmsg): - ... - nla_map = (('IFA_UNSPEC', 'hex'), - ('IFA_ADDRESS', 'ipaddr'), - ('IFA_LOCAL', 'ipaddr'), - ...) - -This code will create mapping, where IFA_ADDRESS NLA will be of -type 1 and IFA_LOCAL -- of type 2, etc. Both NLA will be decoded -as IP addresses (class `ipaddr`). IFA_UNSPEC will be of type 0, -and if it will be in the NLA tree, it will be just dumped in hex. - -NLA class names are should be specified as strings, since they -are resolved in runtime. - -There are several pre-defined NLA types, that you will get with -`nla` class: - - - none # forces pyroute2 just to skip this NLA - - uint8 - - uint16 - - uint32 # there are dedicated NLA of these types as well - - ipaddr # IP address, IPv4 or IPv6, depending on the socket - - l2addr # MAC address - - hex # hex dump as a string -- useful for debugging - - cdata # just a binary string - - asciiz # zero-terminated ASCII string - -Please refer to `pyroute2/netlink/__init__.py` for details. - -You can also make your own NLA descriptions:: - - class ifaddrmsg(nlmsg): - ... - nla_map = (... - ('IFA_CACHEINFO', 'cacheinfo'), - ...) - - class cacheinfo(nla): - fields = (('ifa_prefered', 'I'), - ('ifa_valid', 'I'), - ('cstamp', 'I'), - ('tstamp', 'I')) - -Custom NLA descriptions should be defined in the same class, -where they are used. - -Also, it is possible to use not autogenerated type numbers, as -for ifaddrmsg, but specify them explicitly:: - - class iw_event(nla): - ... - nla_map = ((0x8B00, 'SIOCSIWCOMMIT', 'hex'), - (0x8B01, 'SIOCGIWNAME', 'hex'), - (0x8B02, 'SIOCSIWNWID', 'hex'), - (0x8B03, 'SIOCGIWNWID', 'hex'), - ...) - -Here you can see custom NLA type numbers -- 0x8B00, 0x8B01 etc. -It is not permitted to mix these two forms in one class: you should -use ether autogenerated type numbers (two fields tuples), or -explicit numbers (three fields typles). - -parsed netlink message ----------------------- - -Netlink messages are represented by pyroute2 as dictionaries -as follows:: - - {'header': {'pid': ..., - 'length: ..., - 'flags': ..., - 'error': None, # if you are lucky - 'type': ..., - 'sequence_number': ...}, - - # fields attributes - 'field_name1': value, - ... - 'field_nameX': value, - - # nla tree - 'attrs': [['NLA_NAME1', value], - ... - ['NLA_NAMEX', value], - ['NLA_NAMEY', {'field_name1': value, - ... - 'field_nameX': value, - 'attrs': [['NLA_NAME.... ]]}]]} - -As an example, a message from the wireless subsystem about new -scan event:: - - {'index': 4, - 'family': 0, - '__align': 0, - 'header': {'pid': 0, - 'length': 64, - 'flags': 0, - 'error': None, - 'type': 16, - 'sequence_number': 0}, - 'flags': 69699, - 'ifi_type': 1, - 'event': 'RTM_NEWLINK', - 'change': 0, - 'attrs': [['IFLA_IFNAME', 'wlp3s0'], - ['IFLA_WIRELESS', - {'attrs': [['SIOCGIWSCAN', - '00:00:00:00:00:00:00:00:00:00:00:00']]}]]} - -create and send messages ------------------------- - -Using high-level interfaces like `IPRoute` or `IPDB`, you will never -need to manually construct and send netlink messages. But in the case -you really need it, it is simple as well. - -Having a description class, like `ifaddrmsg` from above, you need to: - - - instantiate it - - fill the fields - - encode the packet - - send the encoded data - -The code:: - - from pyroute2.netlink import NLM_F_REQUEST - from pyroute2.netlink import NLM_F_ACK - from pyroute2.netlink import NLM_F_CREATE - from pyroute2.netlink import NLM_F_EXCL - from pyroute2.iproute import RTM_NEWADDR - from pyroute2.netlink.rtnl.ifaddrmsg import ifaddrmsg - - ## - # add an addr to an interface - # - - # create the message - msg = ifaddrmsg() - - # fill the protocol-specific fields - msg['index'] = index # index of the interface - msg['family'] = AF_INET # address family - msg['prefixlen'] = 24 # the address mask - msg['scope'] = scope # see /etc/iproute2/rt_scopes - - # attach NLA -- it MUST be a list / mutable - msg['attrs'] = [['IFA_LOCAL', '192.168.0.1'], - ['IFA_ADDRESS', '192.162.0.1']] - - # fill generic netlink fields - msg['header']['sequence_number'] = nonce # an unique seq number - msg['header']['pid'] = os.getpid() - msg['header']['type'] = RTM_NEWADDR - msg['header']['flags'] = NLM_F_REQUEST |\\ - NLM_F_ACK |\\ - NLM_F_CREATE |\\ - NLM_F_EXCL - - # encode the packet - msg.encode() - - # send the buffer - nlsock.sendto(msg.buf.getvalue(), (0, 0)) - -Please notice, that NLA list *MUST* be mutable. - ------------------- - -Module contents: -''' - -import traceback -import logging -import socket -import struct -import types -import sys -import io -import re -import os - -from pyroute2.common import hexdump -from pyroute2.common import basestring - -_letters = re.compile('[A-Za-z]') -_fmt_letters = re.compile('[^!><@=][!><@=]') - -## -# That's a hack for the code linter, which works under -# Python3, see unicode reference in the code below -if sys.version[0] == '3': - unicode = str - -NLMSG_MIN_TYPE = 0x10 - -GENL_NAMSIZ = 16 # length of family name -GENL_MIN_ID = NLMSG_MIN_TYPE -GENL_MAX_ID = 1023 - -GENL_ADMIN_PERM = 0x01 -GENL_CMD_CAP_DO = 0x02 -GENL_CMD_CAP_DUMP = 0x04 -GENL_CMD_CAP_HASPOL = 0x08 - -# -# List of reserved static generic netlink identifiers: -# -GENL_ID_GENERATE = 0 -GENL_ID_CTRL = NLMSG_MIN_TYPE - -# -# Controller -# - -CTRL_CMD_UNSPEC = 0x0 -CTRL_CMD_NEWFAMILY = 0x1 -CTRL_CMD_DELFAMILY = 0x2 -CTRL_CMD_GETFAMILY = 0x3 -CTRL_CMD_NEWOPS = 0x4 -CTRL_CMD_DELOPS = 0x5 -CTRL_CMD_GETOPS = 0x6 -CTRL_CMD_NEWMCAST_GRP = 0x7 -CTRL_CMD_DELMCAST_GRP = 0x8 -CTRL_CMD_GETMCAST_GRP = 0x9 # unused - - -CTRL_ATTR_UNSPEC = 0x0 -CTRL_ATTR_FAMILY_ID = 0x1 -CTRL_ATTR_FAMILY_NAME = 0x2 -CTRL_ATTR_VERSION = 0x3 -CTRL_ATTR_HDRSIZE = 0x4 -CTRL_ATTR_MAXATTR = 0x5 -CTRL_ATTR_OPS = 0x6 -CTRL_ATTR_MCAST_GROUPS = 0x7 - -CTRL_ATTR_OP_UNSPEC = 0x0 -CTRL_ATTR_OP_ID = 0x1 -CTRL_ATTR_OP_FLAGS = 0x2 - -CTRL_ATTR_MCAST_GRP_UNSPEC = 0x0 -CTRL_ATTR_MCAST_GRP_NAME = 0x1 -CTRL_ATTR_MCAST_GRP_ID = 0x2 - - -# Different Netlink families -# -NETLINK_ROUTE = 0 # Routing/device hook -NETLINK_UNUSED = 1 # Unused number -NETLINK_USERSOCK = 2 # Reserved for user mode socket protocols -NETLINK_FIREWALL = 3 # Firewalling hook -NETLINK_INET_DIAG = 4 # INET socket monitoring -NETLINK_NFLOG = 5 # netfilter/iptables ULOG -NETLINK_XFRM = 6 # ipsec -NETLINK_SELINUX = 7 # SELinux event notifications -NETLINK_ISCSI = 8 # Open-iSCSI -NETLINK_AUDIT = 9 # auditing -NETLINK_FIB_LOOKUP = 10 -NETLINK_CONNECTOR = 11 -NETLINK_NETFILTER = 12 # netfilter subsystem -NETLINK_IP6_FW = 13 -NETLINK_DNRTMSG = 14 # DECnet routing messages -NETLINK_KOBJECT_UEVENT = 15 # Kernel messages to userspace -NETLINK_GENERIC = 16 -# leave room for NETLINK_DM (DM Events) -NETLINK_SCSITRANSPORT = 18 # SCSI Transports - -# NLA flags -NLA_F_NESTED = 1 << 15 -NLA_F_NET_BYTEORDER = 1 << 14 - -NLMSG_ALIGNTO = 4 - - -class NetlinkError(Exception): - ''' - Base netlink error - ''' - def __init__(self, code, msg=None): - msg = msg or os.strerror(code) - super(NetlinkError, self).__init__(code, msg) - self.code = code - - -class NetlinkDecodeError(Exception): - ''' - Base decoding error class. - - Incapsulates underlying error for the following analysis - ''' - def __init__(self, exception): - self.exception = exception - - -class NetlinkHeaderDecodeError(NetlinkDecodeError): - ''' - The error occured while decoding a header - ''' - pass - - -class NetlinkDataDecodeError(NetlinkDecodeError): - ''' - The error occured while decoding the message fields - ''' - pass - - -class NetlinkNLADecodeError(NetlinkDecodeError): - ''' - The error occured while decoding NLA chain - ''' - pass - - -def NLMSG_ALIGN(l): - return (l + NLMSG_ALIGNTO - 1) & ~ (NLMSG_ALIGNTO - 1) - - -class NotInitialized(Exception): - pass - - -# Netlink message flags values (nlmsghdr.flags) -# -NLM_F_REQUEST = 1 # It is request message. -NLM_F_MULTI = 2 # Multipart message, terminated by NLMSG_DONE -NLM_F_ACK = 4 # Reply with ack, with zero or error code -NLM_F_ECHO = 8 # Echo this request -# Modifiers to GET request -NLM_F_ROOT = 0x100 # specify tree root -NLM_F_MATCH = 0x200 # return all matching -NLM_F_ATOMIC = 0x400 # atomic GET -NLM_F_DUMP = (NLM_F_ROOT | NLM_F_MATCH) -# Modifiers to NEW request -NLM_F_REPLACE = 0x100 # Override existing -NLM_F_EXCL = 0x200 # Do not touch, if it exists -NLM_F_CREATE = 0x400 # Create, if it does not exist -NLM_F_APPEND = 0x800 # Add to end of list - -NLMSG_NOOP = 0x1 # Nothing -NLMSG_ERROR = 0x2 # Error -NLMSG_DONE = 0x3 # End of a dump -NLMSG_OVERRUN = 0x4 # Data lost -NLMSG_CONTROL = 0xe # Custom message type for messaging control -NLMSG_TRANSPORT = 0xf # Custom message type for NL as a transport -NLMSG_MIN_TYPE = 0x10 # < 0x10: reserved control messages -NLMSG_MAX_LEN = 0xffff # Max message length - -mtypes = {1: 'NLMSG_NOOP', - 2: 'NLMSG_ERROR', - 3: 'NLMSG_DONE', - 4: 'NLMSG_OVERRUN'} - -IPRCMD_NOOP = 0 -IPRCMD_STOP = 1 -IPRCMD_ACK = 2 -IPRCMD_ERR = 3 -IPRCMD_REGISTER = 4 -IPRCMD_RELOAD = 5 -IPRCMD_ROUTE = 6 -IPRCMD_CONNECT = 7 -IPRCMD_DISCONNECT = 8 -IPRCMD_SERVE = 9 -IPRCMD_SHUTDOWN = 10 -IPRCMD_SUBSCRIBE = 11 -IPRCMD_UNSUBSCRIBE = 12 -IPRCMD_PROVIDE = 13 -IPRCMD_REMOVE = 14 -IPRCMD_DISCOVER = 15 -IPRCMD_UNREGISTER = 16 - -SOL_NETLINK = 270 - -NETLINK_ADD_MEMBERSHIP = 1 -NETLINK_DROP_MEMBERSHIP = 2 -NETLINK_PKTINFO = 3 -NETLINK_BROADCAST_ERROR = 4 -NETLINK_NO_ENOBUFS = 5 -NETLINK_RX_RING = 6 -NETLINK_TX_RING = 7 - - -class nlmsg_base(dict): - ''' - Netlink base class. You do not need to inherit it directly, unless - you're inventing completely new protocol structure. - - Use nlmsg or nla classes. - - The class provides several methods, but often one need to customize - only `decode()` and `encode()`. - ''' - - fields = [] # data field names, to build a dictionary - header = None # optional header class - pack = None # pack pragma - array = False - nla_map = {} # NLA mapping - nla_flags = 0 # NLA flags - value_map = {} - - def __init__(self, buf=None, length=None, parent=None, debug=False): - dict.__init__(self) - for i in self.fields: - self[i[0]] = 0 # FIXME: only for number values - self.raw = None - self.debug = debug - self.length = length or 0 - self.parent = parent - self.offset = 0 - self.prefix = None - self['attrs'] = [] - self['value'] = NotInitialized - self.value = NotInitialized - self.register_nlas() - self.r_value_map = dict([(x[1], x[0]) for x in self.value_map.items()]) - self.reset(buf) - self.clean_cbs = [] - if self.header is not None: - self['header'] = self.header(self.buf) - - def copy(self): - ''' - Return a decoded copy of the netlink message. Works - correctly only if the message was encoded, or is - received from the socket. - ''' - ret = type(self)(self.buf.getvalue()) - ret.decode() - return ret - - def reset(self, buf=None): - ''' - Reset the message buffer. Optionally, set the message - from the `buf` parameter. This parameter can be either - string, or io.BytesIO, or dict instance. - ''' - if isinstance(buf, basestring): - b = io.BytesIO() - b.write(buf) - b.seek(0) - buf = b - if isinstance(buf, dict): - self.setvalue(buf) - buf = None - self.buf = buf or io.BytesIO() - if 'header' in self: - self['header'].buf = self.buf - - def register_clean_cb(self, cb): - if self.parent is not None: - return self.parent.register_clean_cb(cb) - else: - self.clean_cbs.append(cb) - - def _strip_one(self, name): - for i in tuple(self['attrs']): - if i[0] == name: - self['attrs'].remove(i) - return self - - def strip(self, attrs): - ''' - Remove an NLA from the attrs chain. The `attrs` - parameter can be either string, or iterable. In - the latter case, will be stripped NLAs, specified - in the provided list. - ''' - if isinstance(attrs, basestring): - self._strip_one(attrs) - else: - for name in attrs: - self._strip_one(name) - return self - - def __ops(self, rvalue, op0, op1): - lvalue = self.getvalue() - res = self.__class__() - for key in lvalue: - if key not in ('header', 'attrs'): - if op0 == '__sub__': - # operator -, complement - if (key not in rvalue) or (lvalue[key] != rvalue[key]): - res[key] = lvalue[key] - elif op0 == '__and__': - # operator &, intersection - if (key in rvalue) and (lvalue[key] == rvalue[key]): - res[key] = lvalue[key] - if 'attrs' in lvalue: - res['attrs'] = [] - for attr in lvalue['attrs']: - if isinstance(attr[1], nla): - diff = getattr(attr[1], op0)(rvalue.get_attr(attr[0])) - if diff is not None: - res['attrs'].append([attr[0], diff]) - else: - if op0 == '__sub__': - # operator -, complement - if rvalue.get_attr(attr[0]) != attr[1]: - res['attrs'].append(attr) - elif op0 == '__and__': - # operator &, intersection - if rvalue.get_attr(attr[0]) == attr[1]: - res['attrs'].append(attr) - if not len(res): - return None - else: - if 'header' in res: - del res['header'] - if 'value' in res: - del res['value'] - if 'attrs' in res and not len(res['attrs']): - del res['attrs'] - return res - - def __sub__(self, rvalue): - ''' - Subjunction operation. - ''' - return self.__ops(rvalue, '__sub__', '__ne__') - - def __and__(self, rvalue): - ''' - Conjunction operation. - ''' - return self.__ops(rvalue, '__and__', '__eq__') - - def __eq__(self, rvalue): - ''' - Having nla, we are able to use it in operations like:: - - if nla == 'some value': - ... - ''' - lvalue = self.getvalue() - if lvalue is self: - for key in self: - try: - assert self.get(key) == rvalue.get(key) - except Exception: - # on any error -- is not equal - return False - return True - else: - return lvalue == rvalue - - @classmethod - def get_size(self): - size = 0 - for field in self.fields: - size += struct.calcsize(field[1]) - return size - - @classmethod - def nla2name(self, name): - ''' - Convert NLA name into human-friendly name - - Example: IFLA_ADDRESS -> address - - Requires self.prefix to be set - ''' - return name[(name.find(self.prefix) + 1) * len(self.prefix):].lower() - - @classmethod - def name2nla(self, name): - ''' - Convert human-friendly name into NLA name - - Example: address -> IFLA_ADDRESS - - Requires self.prefix to be set - ''' - name = name.upper() - if name.find(self.prefix) == -1: - name = "%s%s" % (self.prefix, name) - return name - - def reserve(self): - ''' - Reserve space in the buffer for data. This can be used - to skip encoding of the header until some fields will - be known. - ''' - size = 0 - for i in self.fields: - size += struct.calcsize(i[1]) - self.buf.seek(size, 1) - - def decode(self): - ''' - Decode the message. The message should have the `buf` - attribute initialized. e.g.:: - - data = sock.recv(16384) - msg = ifinfmsg(data) - - If you want to customize the decoding process, override - the method, but don't forget to call parent's `decode()`:: - - class CustomMessage(nlmsg): - - def decode(self): - nlmsg.decode(self) - ... # do some custom data tuning - ''' - self.offset = self.buf.tell() - # decode the header - if self.header is not None: - try: - self['header'].decode() - # update length from header - # it can not be less than 4 - self.length = max(self['header']['length'], 4) - save = self.buf.tell() - self.buf.seek(self.offset) - self.raw = self.buf.read(self.length) - self.buf.seek(save) - except Exception as e: - raise NetlinkHeaderDecodeError(e) - # handle the array case - if self.array: - self.setvalue([]) - while self.buf.tell() < self.offset + self.length: - cell = type(self)(self.buf, parent=self, debug=self.debug) - cell.array = False - cell.decode() - self.value.append(cell) - # decode the data - try: - if self.pack == 'struct': - names = [] - formats = [] - for field in self.fields: - names.append(field[0]) - formats.append(field[1]) - fields = ((','.join(names), ''.join(formats)), ) - else: - fields = self.fields - - for field in fields: - name = field[0] - fmt = field[1] - - # 's' and 'z' can be used only in connection with - # length, encoded in the header - if field[1] in ('s', 'z'): - fmt = '%is' % (self.length - 4) - - size = struct.calcsize(fmt) - raw = self.buf.read(size) - actual_size = len(raw) - - # FIXME: adjust string size again - if field[1] in ('s', 'z'): - size = actual_size - fmt = '%is' % (actual_size) - if size == actual_size: - value = struct.unpack(fmt, raw) - if len(value) == 1: - self[name] = value[0] - # cut zero-byte from z-strings - # 0x00 -- python3; '\0' -- python2 - if field[1] == 'z' and self[name][-1] in (0x00, '\0'): - self[name] = self[name][:-1] - else: - if self.pack == 'struct': - names = name.split(',') - values = list(value) - for name in names: - if name[0] != '_': - self[name] = values.pop(0) - else: - self[name] = value - - else: - # FIXME: log an error - pass - - except Exception as e: - raise NetlinkDataDecodeError(e) - # decode NLA - try: - # align NLA chain start - self.buf.seek(NLMSG_ALIGN(self.buf.tell())) - # read NLA chain - if self.nla_map: - self.decode_nlas() - except Exception as e: - logging.warning(traceback.format_exc()) - raise NetlinkNLADecodeError(e) - if len(self['attrs']) == 0: - del self['attrs'] - if self['value'] is NotInitialized: - del self['value'] - - def encode(self): - ''' - Encode the message into the binary buffer:: - - msg.encode() - sock.send(msg.buf.getvalue()) - - If you want to customize the encoding process, override - the method:: - - class CustomMessage(nlmsg): - - def encode(self): - ... # do some custom data tuning - nlmsg.encode(self) - ''' - init = self.buf.tell() - diff = 0 - # reserve space for the header - if self.header is not None: - self['header'].reserve() - - if self.getvalue() is not None: - - payload = b'' - for i in self.fields: - name = i[0] - fmt = i[1] - value = self[name] - - if fmt == 's': - length = len(value) - fmt = '%is' % (length) - elif fmt == 'z': - length = len(value) + 1 - fmt = '%is' % (length) - - # in python3 we should force it - if sys.version[0] == '3': - if isinstance(value, str): - value = bytes(value, 'utf-8') - elif isinstance(value, float): - value = int(value) - elif sys.version[0] == '2': - if isinstance(value, unicode): - value = value.encode('utf-8') - - try: - if fmt[-1] == 'x': - payload += struct.pack(fmt) - elif type(value) in (list, tuple, set): - payload += struct.pack(fmt, *value) - else: - payload += struct.pack(fmt, value) - except struct.error: - logging.error(traceback.format_exc()) - logging.error("error pack: %s %s %s" % - (fmt, value, type(value))) - raise - - diff = NLMSG_ALIGN(len(payload)) - len(payload) - self.buf.write(payload) - self.buf.write(b'\0' * diff) - # write NLA chain - if self.nla_map: - diff = 0 - self.encode_nlas() - # calculate the size and write it - if self.header is not None: - self.update_length(init, diff) - - def update_length(self, start, diff=0): - save = self.buf.tell() - self['header']['length'] = save - start - diff - self.buf.seek(start) - self['header'].encode() - self.buf.seek(save) - - def setvalue(self, value): - if isinstance(value, dict): - self.update(value) - else: - try: - value = self.r_value_map.get(value, value) - except TypeError: - pass - self['value'] = value - self.value = value - - def get_encoded(self, attr, default=None): - ''' - Return the first encoded NLA by name - ''' - return self.get_attr(attr, default, 'encoded') - - def get_attr(self, attr, default=None, fmt='raw'): - ''' - Return the first attr by name or None - ''' - try: - attrs = self.get_attrs(attr, fmt) - except KeyError: - return default - if attrs: - return attrs[0] - else: - return default - - def get_attrs(self, attr, fmt='raw'): - ''' - Return attrs by name - ''' - fmt_map = {'raw': 1, - 'encoded': 2} - return [i[fmt_map[fmt]] for i in self['attrs'] if i[0] == attr] - - def getvalue(self): - ''' - Atomic NLAs return their value in the 'value' field, - not as a dictionary. Complex NLAs return whole dictionary. - ''' - if self.value != NotInitialized: - # value decoded by custom decoder - return self.value - - if 'value' in self and self['value'] != NotInitialized: - # raw value got by generic decoder - return self.value_map.get(self['value'], self['value']) - - return self - - def register_nlas(self): - ''' - Convert 'nla_map' tuple into two dictionaries for mapping - and reverse mapping of NLA types. - - ex: given:: - - nla_map = (('TCA_HTB_UNSPEC', 'none'), - ('TCA_HTB_PARMS', 'htb_parms'), - ('TCA_HTB_INIT', 'htb_glob')) - - creates:: - - t_nla_map = {0: (<class 'pyroute2...none'>, 'TCA_HTB_UNSPEC'), - 1: (<class 'pyroute2...htb_parms'>, 'TCA_HTB_PARMS'), - 2: (<class 'pyroute2...htb_glob'>, 'TCA_HTB_INIT')} - r_nla_map = {'TCA_HTB_UNSPEC': (<class 'pyroute2...none'>, 0), - 'TCA_HTB_PARMS': (<class 'pyroute2...htb_parms'>, 1), - 'TCA_HTB_INIT': (<class 'pyroute2...htb_glob'>, 2)} - - nla_map format:: - - nla_map = (([ID, ] NAME, TYPE[, FLAGS]), ...) - - Items in `[...]` are optional. If ID is not given, then the map will - be autonumerated from 0. If flags are not given, they are 0 by default. - - ''' - # clean up NLA mappings - self.t_nla_map = {} - self.r_nla_map = {} - - # work only on non-empty mappings - if not self.nla_map: - return - - # fix nla flags - nla_map = [] - for item in self.nla_map: - if not isinstance(item[-1], int): - item = list(item) - item.append(0) - nla_map.append(item) - - # detect, whether we have pre-defined keys - if not isinstance(nla_map[0][0], int): - # create enumeration - nla_types = enumerate((i[0] for i in nla_map)) - # that's a little bit tricky, but to reduce - # the required amount of code in modules, we have - # to jump over the head - zipped = [(k[1][0], k[0][0], k[0][1], k[0][2]) for k in - zip(nla_map, nla_types)] - else: - zipped = nla_map - - for (key, name, nla_class, nla_flags) in zipped: - # is it an array - if nla_class[0] == '*': - nla_class = nla_class[1:] - array = True - else: - array = False - # lookup NLA class - if nla_class == 'recursive': - nla_class = type(self) - else: - nla_class = getattr(self, nla_class) - # update mappings - self.t_nla_map[key] = (nla_class, name, nla_flags, array) - self.r_nla_map[name] = (nla_class, key, nla_flags, array) - - def encode_nlas(self): - ''' - Encode the NLA chain. Should not be called manually, since - it is called from `encode()` routine. - ''' - for i in self['attrs']: - if i[0] in self.r_nla_map: - msg_class = self.r_nla_map[i[0]][0] - msg_type = self.r_nla_map[i[0]][1] - # is it a class or a function? - if isinstance(msg_class, types.MethodType): - # if it is a function -- use it to get the class - msg_class = msg_class() - # encode NLA - nla = msg_class(self.buf, parent=self) - nla.nla_flags |= self.r_nla_map[i[0]][2] - nla['header']['type'] = msg_type | nla.nla_flags - nla.setvalue(i[1]) - try: - nla.encode() - except: - raise - else: - if len(i) == 2: - i.append(nla) - elif len(i) == 3: - i[2] = nla - - def decode_nlas(self): - ''' - Decode the NLA chain. Should not be called manually, since - it is called from `decode()` routine. - ''' - while self.buf.tell() < (self.offset + self.length): - init = self.buf.tell() - nla = None - # pick the length and the type - (length, msg_type) = struct.unpack('HH', self.buf.read(4)) - # first two bits of msg_type are flags: - msg_type = msg_type & ~(NLA_F_NESTED | NLA_F_NET_BYTEORDER) - # rewind to the beginning - self.buf.seek(init) - length = min(max(length, 4), - (self.length - self.buf.tell() + self.offset)) - - # we have a mapping for this NLA - if msg_type in self.t_nla_map: - # get the class - msg_class = self.t_nla_map[msg_type][0] - # is it a class or a function? - if isinstance(msg_class, types.MethodType): - # if it is a function -- use it to get the class - msg_class = msg_class(buf=self.buf, length=length) - # and the name - msg_name = self.t_nla_map[msg_type][1] - # is it an array? - msg_array = self.t_nla_map[msg_type][3] - # decode NLA - nla = msg_class(self.buf, length, self, debug=self.debug) - nla.array = msg_array - try: - nla.decode() - nla.nla_flags = msg_type & (NLA_F_NESTED | - NLA_F_NET_BYTEORDER) - except Exception: - logging.warning("decoding %s" % (msg_name)) - logging.warning(traceback.format_exc()) - self.buf.seek(init) - msg_name = 'UNDECODED' - msg_value = hexdump(self.buf.read(length)) - else: - msg_value = nla.getvalue() - else: - msg_name = 'UNKNOWN' - msg_value = hexdump(self.buf.read(length)) - - self['attrs'].append([msg_name, msg_value]) - - # fix the offset - self.buf.seek(init + NLMSG_ALIGN(length)) - - -class nla_header(nlmsg_base): - ''' - The NLA header structure: uin16 length and uint16 type. - ''' - fields = (('length', 'H'), - ('type', 'H')) - - -class nla_base(nlmsg_base): - ''' - The NLA base class. Use `nla_header` class as the header. - ''' - header = nla_header - - -class nlmsg_header(nlmsg_base): - ''' - Common netlink message header - ''' - fields = (('length', 'I'), - ('type', 'H'), - ('flags', 'H'), - ('sequence_number', 'I'), - ('pid', 'I')) - - -class nlmsg_atoms(nlmsg_base): - ''' - A collection of base NLA types - ''' - class none(nla_base): - ''' - 'none' type is used to skip decoding of NLA. You can - also use 'hex' type to dump NLA's content. - ''' - def decode(self): - nla_base.decode(self) - self.value = None - - class uint8(nla_base): - fields = [('value', 'B')] - - class uint16(nla_base): - fields = [('value', 'H')] - - class uint32(nla_base): - fields = [('value', 'I')] - - class uint64(nla_base): - fields = [('value', 'Q')] - - class be8(nla_base): - fields = [('value', '>B')] - - class be16(nla_base): - fields = [('value', '>H')] - - class be32(nla_base): - fields = [('value', '>I')] - - class be64(nla_base): - fields = [('value', '>Q')] - - class ipXaddr(nla_base): - fields = [('value', 's')] - family = None - - def encode(self): - self['value'] = socket.inet_pton(self.family, - self.value) - nla_base.encode(self) - - def decode(self): - nla_base.decode(self) - self.value = socket.inet_ntop(self.family, - self['value']) - - class ip4addr(ipXaddr): - ''' - Explicit IPv4 address type class. - ''' - family = socket.AF_INET - - class ip6addr(ipXaddr): - ''' - Explicit IPv6 address type class. - ''' - family = socket.AF_INET6 - - class ipaddr(nla_base): - ''' - This class is used to decode IP addresses according to - the family. Socket library currently supports only two - families, AF_INET and AF_INET6. - - We do not specify here the string size, it will be - calculated in runtime. - ''' - fields = [('value', 's')] - family_map = {socket.AF_INET: socket.AF_INET, - socket.AF_BRIDGE: socket.AF_INET, - socket.AF_INET6: socket.AF_INET6} - - def encode(self): - family = self.family_map[self.parent['family']] - self['value'] = socket.inet_pton(family, self.value) - nla_base.encode(self) - - def decode(self): - nla_base.decode(self) - family = self.family_map[self.parent['family']] - self.value = socket.inet_ntop(family, self['value']) - - class l2addr(nla_base): - ''' - Decode MAC address. - ''' - fields = [('value', '=6s')] - - def encode(self): - self['value'] = struct.pack('BBBBBB', - *[int(i, 16) for i in - self.value.split(':')]) - nla_base.encode(self) - - def decode(self): - nla_base.decode(self) - self.value = ':'.join('%02x' % (i) for i in - struct.unpack('BBBBBB', self['value'])) - - class hex(nla_base): - ''' - Represent NLA's content with header as hex string. - ''' - fields = [('value', 's')] - - def decode(self): - nla_base.decode(self) - self.value = hexdump(self['value']) - - class cdata(nla_base): - ''' - Binary data - ''' - fields = [('value', 's')] - - class asciiz(nla_base): - ''' - Zero-terminated string. - ''' - # FIXME: move z-string hacks from general decode here? - fields = [('value', 'z')] - - def encode(self): - if isinstance(self['value'], str) and sys.version[0] == '3': - self['value'] = bytes(self['value'], 'utf-8') - nla_base.encode(self) - - def decode(self): - nla_base.decode(self) - try: - assert sys.version[0] == '3' - self.value = self['value'].decode('utf-8') - except (AssertionError, UnicodeDecodeError): - self.value = self['value'] - - -class nla(nla_base, nlmsg_atoms): - ''' - Main NLA class - ''' - def decode(self): - nla_base.decode(self) - if not self.debug: - del self['header'] - - -class nlmsg(nlmsg_atoms): - ''' - Main netlink message class - ''' - header = nlmsg_header - - -class genlmsg(nlmsg): - ''' - Generic netlink message - ''' - fields = (('cmd', 'B'), - ('version', 'B'), - ('reserved', 'H')) - - -class ctrlmsg(genlmsg): - ''' - Netlink control message - ''' - # FIXME: to be extended - nla_map = (('CTRL_ATTR_UNSPEC', 'none'), - ('CTRL_ATTR_FAMILY_ID', 'uint16'), - ('CTRL_ATTR_FAMILY_NAME', 'asciiz'), - ('CTRL_ATTR_VERSION', 'uint32'), - ('CTRL_ATTR_HDRSIZE', 'uint32'), - ('CTRL_ATTR_MAXATTR', 'uint32'), - ('CTRL_ATTR_OPS', '*ops'), - ('CTRL_ATTR_MCAST_GROUPS', '*mcast_groups')) - - class ops(nla): - nla_map = (('CTRL_ATTR_OP_UNSPEC', 'none'), - ('CTRL_ATTR_OP_ID', 'uint32'), - ('CTRL_ATTR_OP_FLAGS', 'uint32')) - - class mcast_groups(nla): - nla_map = (('CTRL_ATTR_MCAST_GRP_UNSPEC', 'none'), - ('CTRL_ATTR_MCAST_GRP_NAME', 'asciiz'), - ('CTRL_ATTR_MCAST_GRP_ID', 'uint32')) |