]> git.proxmox.com Git - mirror_ubuntu-kernels.git/commitdiff
tools: ynl: move the cli and netlink code around
authorJakub Kicinski <kuba@kernel.org>
Tue, 31 Jan 2023 02:33:42 +0000 (18:33 -0800)
committerJakub Kicinski <kuba@kernel.org>
Wed, 1 Feb 2023 04:36:03 +0000 (20:36 -0800)
Move the CLI code out of samples/ and the library part
of it into tools/net/ynl/lib/. This way we can start
sharing some code with the code gen.

Initially I thought that code gen is too C-specific to
share anything but basic stuff like calculating values
for enums can easily be shared.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
tools/net/ynl/cli.py [new file with mode: 0755]
tools/net/ynl/lib/__init__.py [new file with mode: 0644]
tools/net/ynl/lib/ynl.py [new file with mode: 0644]
tools/net/ynl/samples/cli.py [deleted file]
tools/net/ynl/samples/ynl.py [deleted file]

diff --git a/tools/net/ynl/cli.py b/tools/net/ynl/cli.py
new file mode 100755 (executable)
index 0000000..5c4eb5a
--- /dev/null
@@ -0,0 +1,47 @@
+#!/usr/bin/env python
+# SPDX-License-Identifier: BSD-3-Clause
+
+import argparse
+import json
+import pprint
+import time
+
+from lib import YnlFamily
+
+
+def main():
+    parser = argparse.ArgumentParser(description='YNL CLI sample')
+    parser.add_argument('--spec', dest='spec', type=str, required=True)
+    parser.add_argument('--schema', dest='schema', type=str)
+    parser.add_argument('--json', dest='json_text', type=str)
+    parser.add_argument('--do', dest='do', type=str)
+    parser.add_argument('--dump', dest='dump', type=str)
+    parser.add_argument('--sleep', dest='sleep', type=int)
+    parser.add_argument('--subscribe', dest='ntf', type=str)
+    args = parser.parse_args()
+
+    attrs = {}
+    if args.json_text:
+        attrs = json.loads(args.json_text)
+
+    ynl = YnlFamily(args.spec, args.schema)
+
+    if args.ntf:
+        ynl.ntf_subscribe(args.ntf)
+
+    if args.sleep:
+        time.sleep(args.sleep)
+
+    if args.do or args.dump:
+        method = getattr(ynl, args.do if args.do else args.dump)
+
+        reply = method(attrs, dump=bool(args.dump))
+        pprint.PrettyPrinter().pprint(reply)
+
+    if args.ntf:
+        ynl.check_ntf()
+        pprint.PrettyPrinter().pprint(ynl.async_msg_queue)
+
+
+if __name__ == "__main__":
+    main()
diff --git a/tools/net/ynl/lib/__init__.py b/tools/net/ynl/lib/__init__.py
new file mode 100644 (file)
index 0000000..0a61027
--- /dev/null
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: BSD-3-Clause
+
+from .ynl import YnlFamily
+
+__all__ = ["YnlFamily"]
diff --git a/tools/net/ynl/lib/ynl.py b/tools/net/ynl/lib/ynl.py
new file mode 100644 (file)
index 0000000..b71523d
--- /dev/null
@@ -0,0 +1,534 @@
+# SPDX-License-Identifier: BSD-3-Clause
+
+import functools
+import jsonschema
+import os
+import random
+import socket
+import struct
+import yaml
+
+#
+# Generic Netlink code which should really be in some library, but I can't quickly find one.
+#
+
+
+class Netlink:
+    # Netlink socket
+    SOL_NETLINK = 270
+
+    NETLINK_ADD_MEMBERSHIP = 1
+    NETLINK_CAP_ACK = 10
+    NETLINK_EXT_ACK = 11
+
+    # Netlink message
+    NLMSG_ERROR = 2
+    NLMSG_DONE = 3
+
+    NLM_F_REQUEST = 1
+    NLM_F_ACK = 4
+    NLM_F_ROOT = 0x100
+    NLM_F_MATCH = 0x200
+    NLM_F_APPEND = 0x800
+
+    NLM_F_CAPPED = 0x100
+    NLM_F_ACK_TLVS = 0x200
+
+    NLM_F_DUMP = NLM_F_ROOT | NLM_F_MATCH
+
+    NLA_F_NESTED = 0x8000
+    NLA_F_NET_BYTEORDER = 0x4000
+
+    NLA_TYPE_MASK = NLA_F_NESTED | NLA_F_NET_BYTEORDER
+
+    # Genetlink defines
+    NETLINK_GENERIC = 16
+
+    GENL_ID_CTRL = 0x10
+
+    # nlctrl
+    CTRL_CMD_GETFAMILY = 3
+
+    CTRL_ATTR_FAMILY_ID = 1
+    CTRL_ATTR_FAMILY_NAME = 2
+    CTRL_ATTR_MAXATTR = 5
+    CTRL_ATTR_MCAST_GROUPS = 7
+
+    CTRL_ATTR_MCAST_GRP_NAME = 1
+    CTRL_ATTR_MCAST_GRP_ID = 2
+
+    # Extack types
+    NLMSGERR_ATTR_MSG = 1
+    NLMSGERR_ATTR_OFFS = 2
+    NLMSGERR_ATTR_COOKIE = 3
+    NLMSGERR_ATTR_POLICY = 4
+    NLMSGERR_ATTR_MISS_TYPE = 5
+    NLMSGERR_ATTR_MISS_NEST = 6
+
+
+class NlAttr:
+    def __init__(self, raw, offset):
+        self._len, self._type = struct.unpack("HH", raw[offset:offset + 4])
+        self.type = self._type & ~Netlink.NLA_TYPE_MASK
+        self.payload_len = self._len
+        self.full_len = (self.payload_len + 3) & ~3
+        self.raw = raw[offset + 4:offset + self.payload_len]
+
+    def as_u16(self):
+        return struct.unpack("H", self.raw)[0]
+
+    def as_u32(self):
+        return struct.unpack("I", self.raw)[0]
+
+    def as_u64(self):
+        return struct.unpack("Q", self.raw)[0]
+
+    def as_strz(self):
+        return self.raw.decode('ascii')[:-1]
+
+    def as_bin(self):
+        return self.raw
+
+    def __repr__(self):
+        return f"[type:{self.type} len:{self._len}] {self.raw}"
+
+
+class NlAttrs:
+    def __init__(self, msg):
+        self.attrs = []
+
+        offset = 0
+        while offset < len(msg):
+            attr = NlAttr(msg, offset)
+            offset += attr.full_len
+            self.attrs.append(attr)
+
+    def __iter__(self):
+        yield from self.attrs
+
+    def __repr__(self):
+        msg = ''
+        for a in self.attrs:
+            if msg:
+                msg += '\n'
+            msg += repr(a)
+        return msg
+
+
+class NlMsg:
+    def __init__(self, msg, offset, attr_space=None):
+        self.hdr = msg[offset:offset + 16]
+
+        self.nl_len, self.nl_type, self.nl_flags, self.nl_seq, self.nl_portid = \
+            struct.unpack("IHHII", self.hdr)
+
+        self.raw = msg[offset + 16:offset + self.nl_len]
+
+        self.error = 0
+        self.done = 0
+
+        extack_off = None
+        if self.nl_type == Netlink.NLMSG_ERROR:
+            self.error = struct.unpack("i", self.raw[0:4])[0]
+            self.done = 1
+            extack_off = 20
+        elif self.nl_type == Netlink.NLMSG_DONE:
+            self.done = 1
+            extack_off = 4
+
+        self.extack = None
+        if self.nl_flags & Netlink.NLM_F_ACK_TLVS and extack_off:
+            self.extack = dict()
+            extack_attrs = NlAttrs(self.raw[extack_off:])
+            for extack in extack_attrs:
+                if extack.type == Netlink.NLMSGERR_ATTR_MSG:
+                    self.extack['msg'] = extack.as_strz()
+                elif extack.type == Netlink.NLMSGERR_ATTR_MISS_TYPE:
+                    self.extack['miss-type'] = extack.as_u32()
+                elif extack.type == Netlink.NLMSGERR_ATTR_MISS_NEST:
+                    self.extack['miss-nest'] = extack.as_u32()
+                elif extack.type == Netlink.NLMSGERR_ATTR_OFFS:
+                    self.extack['bad-attr-offs'] = extack.as_u32()
+                else:
+                    if 'unknown' not in self.extack:
+                        self.extack['unknown'] = []
+                    self.extack['unknown'].append(extack)
+
+            if attr_space:
+                # We don't have the ability to parse nests yet, so only do global
+                if 'miss-type' in self.extack and 'miss-nest' not in self.extack:
+                    miss_type = self.extack['miss-type']
+                    if len(attr_space.attr_list) > miss_type:
+                        spec = attr_space.attr_list[miss_type]
+                        desc = spec['name']
+                        if 'doc' in spec:
+                            desc += f" ({spec['doc']})"
+                        self.extack['miss-type'] = desc
+
+    def __repr__(self):
+        msg = f"nl_len = {self.nl_len} ({len(self.raw)}) nl_flags = 0x{self.nl_flags:x} nl_type = {self.nl_type}\n"
+        if self.error:
+            msg += '\terror: ' + str(self.error)
+        if self.extack:
+            msg += '\textack: ' + repr(self.extack)
+        return msg
+
+
+class NlMsgs:
+    def __init__(self, data, attr_space=None):
+        self.msgs = []
+
+        offset = 0
+        while offset < len(data):
+            msg = NlMsg(data, offset, attr_space=attr_space)
+            offset += msg.nl_len
+            self.msgs.append(msg)
+
+    def __iter__(self):
+        yield from self.msgs
+
+
+genl_family_name_to_id = None
+
+
+def _genl_msg(nl_type, nl_flags, genl_cmd, genl_version, seq=None):
+    # we prepend length in _genl_msg_finalize()
+    if seq is None:
+        seq = random.randint(1, 1024)
+    nlmsg = struct.pack("HHII", nl_type, nl_flags, seq, 0)
+    genlmsg = struct.pack("bbH", genl_cmd, genl_version, 0)
+    return nlmsg + genlmsg
+
+
+def _genl_msg_finalize(msg):
+    return struct.pack("I", len(msg) + 4) + msg
+
+
+def _genl_load_families():
+    with socket.socket(socket.AF_NETLINK, socket.SOCK_RAW, Netlink.NETLINK_GENERIC) as sock:
+        sock.setsockopt(Netlink.SOL_NETLINK, Netlink.NETLINK_CAP_ACK, 1)
+
+        msg = _genl_msg(Netlink.GENL_ID_CTRL,
+                        Netlink.NLM_F_REQUEST | Netlink.NLM_F_ACK | Netlink.NLM_F_DUMP,
+                        Netlink.CTRL_CMD_GETFAMILY, 1)
+        msg = _genl_msg_finalize(msg)
+
+        sock.send(msg, 0)
+
+        global genl_family_name_to_id
+        genl_family_name_to_id = dict()
+
+        while True:
+            reply = sock.recv(128 * 1024)
+            nms = NlMsgs(reply)
+            for nl_msg in nms:
+                if nl_msg.error:
+                    print("Netlink error:", nl_msg.error)
+                    return
+                if nl_msg.done:
+                    return
+
+                gm = GenlMsg(nl_msg)
+                fam = dict()
+                for attr in gm.raw_attrs:
+                    if attr.type == Netlink.CTRL_ATTR_FAMILY_ID:
+                        fam['id'] = attr.as_u16()
+                    elif attr.type == Netlink.CTRL_ATTR_FAMILY_NAME:
+                        fam['name'] = attr.as_strz()
+                    elif attr.type == Netlink.CTRL_ATTR_MAXATTR:
+                        fam['maxattr'] = attr.as_u32()
+                    elif attr.type == Netlink.CTRL_ATTR_MCAST_GROUPS:
+                        fam['mcast'] = dict()
+                        for entry in NlAttrs(attr.raw):
+                            mcast_name = None
+                            mcast_id = None
+                            for entry_attr in NlAttrs(entry.raw):
+                                if entry_attr.type == Netlink.CTRL_ATTR_MCAST_GRP_NAME:
+                                    mcast_name = entry_attr.as_strz()
+                                elif entry_attr.type == Netlink.CTRL_ATTR_MCAST_GRP_ID:
+                                    mcast_id = entry_attr.as_u32()
+                            if mcast_name and mcast_id is not None:
+                                fam['mcast'][mcast_name] = mcast_id
+                if 'name' in fam and 'id' in fam:
+                    genl_family_name_to_id[fam['name']] = fam
+
+
+class GenlMsg:
+    def __init__(self, nl_msg):
+        self.nl = nl_msg
+
+        self.hdr = nl_msg.raw[0:4]
+        self.raw = nl_msg.raw[4:]
+
+        self.genl_cmd, self.genl_version, _ = struct.unpack("bbH", self.hdr)
+
+        self.raw_attrs = NlAttrs(self.raw)
+
+    def __repr__(self):
+        msg = repr(self.nl)
+        msg += f"\tgenl_cmd = {self.genl_cmd} genl_ver = {self.genl_version}\n"
+        for a in self.raw_attrs:
+            msg += '\t\t' + repr(a) + '\n'
+        return msg
+
+
+class GenlFamily:
+    def __init__(self, family_name):
+        self.family_name = family_name
+
+        global genl_family_name_to_id
+        if genl_family_name_to_id is None:
+            _genl_load_families()
+
+        self.genl_family = genl_family_name_to_id[family_name]
+        self.family_id = genl_family_name_to_id[family_name]['id']
+
+
+#
+# YNL implementation details.
+#
+
+
+class YnlAttrSpace:
+    def __init__(self, family, yaml):
+        self.yaml = yaml
+
+        self.attrs = dict()
+        self.name = self.yaml['name']
+        self.subspace_of = self.yaml['subset-of'] if 'subspace-of' in self.yaml else None
+
+        val = 0
+        max_val = 0
+        for elem in self.yaml['attributes']:
+            if 'value' in elem:
+                val = elem['value']
+            else:
+                elem['value'] = val
+            if val > max_val:
+                max_val = val
+            val += 1
+
+            self.attrs[elem['name']] = elem
+
+        self.attr_list = [None] * (max_val + 1)
+        for elem in self.yaml['attributes']:
+            self.attr_list[elem['value']] = elem
+
+    def __getitem__(self, key):
+        return self.attrs[key]
+
+    def __contains__(self, key):
+        return key in self.yaml
+
+    def __iter__(self):
+        yield from self.attrs
+
+    def items(self):
+        return self.attrs.items()
+
+
+class YnlFamily:
+    def __init__(self, def_path, schema=None):
+        self.include_raw = False
+
+        with open(def_path, "r") as stream:
+            self.yaml = yaml.safe_load(stream)
+
+        if schema:
+            with open(schema, "r") as stream:
+                schema = yaml.safe_load(stream)
+
+            jsonschema.validate(self.yaml, schema)
+
+        self.sock = socket.socket(socket.AF_NETLINK, socket.SOCK_RAW, Netlink.NETLINK_GENERIC)
+        self.sock.setsockopt(Netlink.SOL_NETLINK, Netlink.NETLINK_CAP_ACK, 1)
+        self.sock.setsockopt(Netlink.SOL_NETLINK, Netlink.NETLINK_EXT_ACK, 1)
+
+        self._ops = dict()
+        self._spaces = dict()
+        self._types = dict()
+
+        for elem in self.yaml['attribute-sets']:
+            self._spaces[elem['name']] = YnlAttrSpace(self, elem)
+
+        for elem in self.yaml['definitions']:
+            self._types[elem['name']] = elem
+
+        async_separation = 'async-prefix' in self.yaml['operations']
+        self.async_msg_ids = set()
+        self.async_msg_queue = []
+        val = 0
+        max_val = 0
+        for elem in self.yaml['operations']['list']:
+            if not (async_separation and ('notify' in elem or 'event' in elem)):
+                if 'value' in elem:
+                    val = elem['value']
+                else:
+                    elem['value'] = val
+                val += 1
+                max_val = max(val, max_val)
+
+            if 'notify' in elem or 'event' in elem:
+                self.async_msg_ids.add(elem['value'])
+
+            self._ops[elem['name']] = elem
+
+            op_name = elem['name'].replace('-', '_')
+
+            bound_f = functools.partial(self._op, elem['name'])
+            setattr(self, op_name, bound_f)
+
+        self._op_array = [None] * max_val
+        for _, op in self._ops.items():
+            self._op_array[op['value']] = op
+            if 'notify' in op:
+                op['attribute-set'] = self._ops[op['notify']]['attribute-set']
+
+        self.family = GenlFamily(self.yaml['name'])
+
+    def ntf_subscribe(self, mcast_name):
+        if mcast_name not in self.family.genl_family['mcast']:
+            raise Exception(f'Multicast group "{mcast_name}" not present in the family')
+
+        self.sock.bind((0, 0))
+        self.sock.setsockopt(Netlink.SOL_NETLINK, Netlink.NETLINK_ADD_MEMBERSHIP,
+                             self.family.genl_family['mcast'][mcast_name])
+
+    def _add_attr(self, space, name, value):
+        attr = self._spaces[space][name]
+        nl_type = attr['value']
+        if attr["type"] == 'nest':
+            nl_type |= Netlink.NLA_F_NESTED
+            attr_payload = b''
+            for subname, subvalue in value.items():
+                attr_payload += self._add_attr(attr['nested-attributes'], subname, subvalue)
+        elif attr["type"] == 'u32':
+            attr_payload = struct.pack("I", int(value))
+        elif attr["type"] == 'string':
+            attr_payload = str(value).encode('ascii') + b'\x00'
+        elif attr["type"] == 'binary':
+            attr_payload = value
+        else:
+            raise Exception(f'Unknown type at {space} {name} {value} {attr["type"]}')
+
+        pad = b'\x00' * ((4 - len(attr_payload) % 4) % 4)
+        return struct.pack('HH', len(attr_payload) + 4, nl_type) + attr_payload + pad
+
+    def _decode_enum(self, rsp, attr_spec):
+        raw = rsp[attr_spec['name']]
+        enum = self._types[attr_spec['enum']]
+        i = attr_spec.get('value-start', 0)
+        if 'enum-as-flags' in attr_spec and attr_spec['enum-as-flags']:
+            value = set()
+            while raw:
+                if raw & 1:
+                    value.add(enum['entries'][i])
+                raw >>= 1
+                i += 1
+        else:
+            value = enum['entries'][raw - i]
+        rsp[attr_spec['name']] = value
+
+    def _decode(self, attrs, space):
+        attr_space = self._spaces[space]
+        rsp = dict()
+        for attr in attrs:
+            attr_spec = attr_space.attr_list[attr.type]
+            if attr_spec["type"] == 'nest':
+                subdict = self._decode(NlAttrs(attr.raw), attr_spec['nested-attributes'])
+                rsp[attr_spec['name']] = subdict
+            elif attr_spec['type'] == 'u32':
+                rsp[attr_spec['name']] = attr.as_u32()
+            elif attr_spec['type'] == 'u64':
+                rsp[attr_spec['name']] = attr.as_u64()
+            elif attr_spec["type"] == 'string':
+                rsp[attr_spec['name']] = attr.as_strz()
+            elif attr_spec["type"] == 'binary':
+                rsp[attr_spec['name']] = attr.as_bin()
+            else:
+                raise Exception(f'Unknown {attr.type} {attr_spec["name"]} {attr_spec["type"]}')
+
+            if 'enum' in attr_spec:
+                self._decode_enum(rsp, attr_spec)
+        return rsp
+
+    def handle_ntf(self, nl_msg, genl_msg):
+        msg = dict()
+        if self.include_raw:
+            msg['nlmsg'] = nl_msg
+            msg['genlmsg'] = genl_msg
+        op = self._op_array[genl_msg.genl_cmd]
+        msg['name'] = op['name']
+        msg['msg'] = self._decode(genl_msg.raw_attrs, op['attribute-set'])
+        self.async_msg_queue.append(msg)
+
+    def check_ntf(self):
+        while True:
+            try:
+                reply = self.sock.recv(128 * 1024, socket.MSG_DONTWAIT)
+            except BlockingIOError:
+                return
+
+            nms = NlMsgs(reply)
+            for nl_msg in nms:
+                if nl_msg.error:
+                    print("Netlink error in ntf!?", os.strerror(-nl_msg.error))
+                    print(nl_msg)
+                    continue
+                if nl_msg.done:
+                    print("Netlink done while checking for ntf!?")
+                    continue
+
+                gm = GenlMsg(nl_msg)
+                if gm.genl_cmd not in self.async_msg_ids:
+                    print("Unexpected msg id done while checking for ntf", gm)
+                    continue
+
+                self.handle_ntf(nl_msg, gm)
+
+    def _op(self, method, vals, dump=False):
+        op = self._ops[method]
+
+        nl_flags = Netlink.NLM_F_REQUEST | Netlink.NLM_F_ACK
+        if dump:
+            nl_flags |= Netlink.NLM_F_DUMP
+
+        req_seq = random.randint(1024, 65535)
+        msg = _genl_msg(self.family.family_id, nl_flags, op['value'], 1, req_seq)
+        for name, value in vals.items():
+            msg += self._add_attr(op['attribute-set'], name, value)
+        msg = _genl_msg_finalize(msg)
+
+        self.sock.send(msg, 0)
+
+        done = False
+        rsp = []
+        while not done:
+            reply = self.sock.recv(128 * 1024)
+            nms = NlMsgs(reply, attr_space=self._spaces[op['attribute-set']])
+            for nl_msg in nms:
+                if nl_msg.error:
+                    print("Netlink error:", os.strerror(-nl_msg.error))
+                    print(nl_msg)
+                    return
+                if nl_msg.done:
+                    done = True
+                    break
+
+                gm = GenlMsg(nl_msg)
+                # Check if this is a reply to our request
+                if nl_msg.nl_seq != req_seq or gm.genl_cmd != op['value']:
+                    if gm.genl_cmd in self.async_msg_ids:
+                        self.handle_ntf(nl_msg, gm)
+                        continue
+                    else:
+                        print('Unexpected message: ' + repr(gm))
+                        continue
+
+                rsp.append(self._decode(gm.raw_attrs, op['attribute-set']))
+
+        if not rsp:
+            return None
+        if not dump and len(rsp) == 1:
+            return rsp[0]
+        return rsp
diff --git a/tools/net/ynl/samples/cli.py b/tools/net/ynl/samples/cli.py
deleted file mode 100755 (executable)
index b27159c..0000000
+++ /dev/null
@@ -1,47 +0,0 @@
-#!/usr/bin/env python
-# SPDX-License-Identifier: BSD-3-Clause
-
-import argparse
-import json
-import pprint
-import time
-
-from ynl import YnlFamily
-
-
-def main():
-    parser = argparse.ArgumentParser(description='YNL CLI sample')
-    parser.add_argument('--spec', dest='spec', type=str, required=True)
-    parser.add_argument('--schema', dest='schema', type=str)
-    parser.add_argument('--json', dest='json_text', type=str)
-    parser.add_argument('--do', dest='do', type=str)
-    parser.add_argument('--dump', dest='dump', type=str)
-    parser.add_argument('--sleep', dest='sleep', type=int)
-    parser.add_argument('--subscribe', dest='ntf', type=str)
-    args = parser.parse_args()
-
-    attrs = {}
-    if args.json_text:
-        attrs = json.loads(args.json_text)
-
-    ynl = YnlFamily(args.spec, args.schema)
-
-    if args.ntf:
-        ynl.ntf_subscribe(args.ntf)
-
-    if args.sleep:
-        time.sleep(args.sleep)
-
-    if args.do or args.dump:
-        method = getattr(ynl, args.do if args.do else args.dump)
-
-        reply = method(attrs, dump=bool(args.dump))
-        pprint.PrettyPrinter().pprint(reply)
-
-    if args.ntf:
-        ynl.check_ntf()
-        pprint.PrettyPrinter().pprint(ynl.async_msg_queue)
-
-
-if __name__ == "__main__":
-    main()
diff --git a/tools/net/ynl/samples/ynl.py b/tools/net/ynl/samples/ynl.py
deleted file mode 100644 (file)
index b71523d..0000000
+++ /dev/null
@@ -1,534 +0,0 @@
-# SPDX-License-Identifier: BSD-3-Clause
-
-import functools
-import jsonschema
-import os
-import random
-import socket
-import struct
-import yaml
-
-#
-# Generic Netlink code which should really be in some library, but I can't quickly find one.
-#
-
-
-class Netlink:
-    # Netlink socket
-    SOL_NETLINK = 270
-
-    NETLINK_ADD_MEMBERSHIP = 1
-    NETLINK_CAP_ACK = 10
-    NETLINK_EXT_ACK = 11
-
-    # Netlink message
-    NLMSG_ERROR = 2
-    NLMSG_DONE = 3
-
-    NLM_F_REQUEST = 1
-    NLM_F_ACK = 4
-    NLM_F_ROOT = 0x100
-    NLM_F_MATCH = 0x200
-    NLM_F_APPEND = 0x800
-
-    NLM_F_CAPPED = 0x100
-    NLM_F_ACK_TLVS = 0x200
-
-    NLM_F_DUMP = NLM_F_ROOT | NLM_F_MATCH
-
-    NLA_F_NESTED = 0x8000
-    NLA_F_NET_BYTEORDER = 0x4000
-
-    NLA_TYPE_MASK = NLA_F_NESTED | NLA_F_NET_BYTEORDER
-
-    # Genetlink defines
-    NETLINK_GENERIC = 16
-
-    GENL_ID_CTRL = 0x10
-
-    # nlctrl
-    CTRL_CMD_GETFAMILY = 3
-
-    CTRL_ATTR_FAMILY_ID = 1
-    CTRL_ATTR_FAMILY_NAME = 2
-    CTRL_ATTR_MAXATTR = 5
-    CTRL_ATTR_MCAST_GROUPS = 7
-
-    CTRL_ATTR_MCAST_GRP_NAME = 1
-    CTRL_ATTR_MCAST_GRP_ID = 2
-
-    # Extack types
-    NLMSGERR_ATTR_MSG = 1
-    NLMSGERR_ATTR_OFFS = 2
-    NLMSGERR_ATTR_COOKIE = 3
-    NLMSGERR_ATTR_POLICY = 4
-    NLMSGERR_ATTR_MISS_TYPE = 5
-    NLMSGERR_ATTR_MISS_NEST = 6
-
-
-class NlAttr:
-    def __init__(self, raw, offset):
-        self._len, self._type = struct.unpack("HH", raw[offset:offset + 4])
-        self.type = self._type & ~Netlink.NLA_TYPE_MASK
-        self.payload_len = self._len
-        self.full_len = (self.payload_len + 3) & ~3
-        self.raw = raw[offset + 4:offset + self.payload_len]
-
-    def as_u16(self):
-        return struct.unpack("H", self.raw)[0]
-
-    def as_u32(self):
-        return struct.unpack("I", self.raw)[0]
-
-    def as_u64(self):
-        return struct.unpack("Q", self.raw)[0]
-
-    def as_strz(self):
-        return self.raw.decode('ascii')[:-1]
-
-    def as_bin(self):
-        return self.raw
-
-    def __repr__(self):
-        return f"[type:{self.type} len:{self._len}] {self.raw}"
-
-
-class NlAttrs:
-    def __init__(self, msg):
-        self.attrs = []
-
-        offset = 0
-        while offset < len(msg):
-            attr = NlAttr(msg, offset)
-            offset += attr.full_len
-            self.attrs.append(attr)
-
-    def __iter__(self):
-        yield from self.attrs
-
-    def __repr__(self):
-        msg = ''
-        for a in self.attrs:
-            if msg:
-                msg += '\n'
-            msg += repr(a)
-        return msg
-
-
-class NlMsg:
-    def __init__(self, msg, offset, attr_space=None):
-        self.hdr = msg[offset:offset + 16]
-
-        self.nl_len, self.nl_type, self.nl_flags, self.nl_seq, self.nl_portid = \
-            struct.unpack("IHHII", self.hdr)
-
-        self.raw = msg[offset + 16:offset + self.nl_len]
-
-        self.error = 0
-        self.done = 0
-
-        extack_off = None
-        if self.nl_type == Netlink.NLMSG_ERROR:
-            self.error = struct.unpack("i", self.raw[0:4])[0]
-            self.done = 1
-            extack_off = 20
-        elif self.nl_type == Netlink.NLMSG_DONE:
-            self.done = 1
-            extack_off = 4
-
-        self.extack = None
-        if self.nl_flags & Netlink.NLM_F_ACK_TLVS and extack_off:
-            self.extack = dict()
-            extack_attrs = NlAttrs(self.raw[extack_off:])
-            for extack in extack_attrs:
-                if extack.type == Netlink.NLMSGERR_ATTR_MSG:
-                    self.extack['msg'] = extack.as_strz()
-                elif extack.type == Netlink.NLMSGERR_ATTR_MISS_TYPE:
-                    self.extack['miss-type'] = extack.as_u32()
-                elif extack.type == Netlink.NLMSGERR_ATTR_MISS_NEST:
-                    self.extack['miss-nest'] = extack.as_u32()
-                elif extack.type == Netlink.NLMSGERR_ATTR_OFFS:
-                    self.extack['bad-attr-offs'] = extack.as_u32()
-                else:
-                    if 'unknown' not in self.extack:
-                        self.extack['unknown'] = []
-                    self.extack['unknown'].append(extack)
-
-            if attr_space:
-                # We don't have the ability to parse nests yet, so only do global
-                if 'miss-type' in self.extack and 'miss-nest' not in self.extack:
-                    miss_type = self.extack['miss-type']
-                    if len(attr_space.attr_list) > miss_type:
-                        spec = attr_space.attr_list[miss_type]
-                        desc = spec['name']
-                        if 'doc' in spec:
-                            desc += f" ({spec['doc']})"
-                        self.extack['miss-type'] = desc
-
-    def __repr__(self):
-        msg = f"nl_len = {self.nl_len} ({len(self.raw)}) nl_flags = 0x{self.nl_flags:x} nl_type = {self.nl_type}\n"
-        if self.error:
-            msg += '\terror: ' + str(self.error)
-        if self.extack:
-            msg += '\textack: ' + repr(self.extack)
-        return msg
-
-
-class NlMsgs:
-    def __init__(self, data, attr_space=None):
-        self.msgs = []
-
-        offset = 0
-        while offset < len(data):
-            msg = NlMsg(data, offset, attr_space=attr_space)
-            offset += msg.nl_len
-            self.msgs.append(msg)
-
-    def __iter__(self):
-        yield from self.msgs
-
-
-genl_family_name_to_id = None
-
-
-def _genl_msg(nl_type, nl_flags, genl_cmd, genl_version, seq=None):
-    # we prepend length in _genl_msg_finalize()
-    if seq is None:
-        seq = random.randint(1, 1024)
-    nlmsg = struct.pack("HHII", nl_type, nl_flags, seq, 0)
-    genlmsg = struct.pack("bbH", genl_cmd, genl_version, 0)
-    return nlmsg + genlmsg
-
-
-def _genl_msg_finalize(msg):
-    return struct.pack("I", len(msg) + 4) + msg
-
-
-def _genl_load_families():
-    with socket.socket(socket.AF_NETLINK, socket.SOCK_RAW, Netlink.NETLINK_GENERIC) as sock:
-        sock.setsockopt(Netlink.SOL_NETLINK, Netlink.NETLINK_CAP_ACK, 1)
-
-        msg = _genl_msg(Netlink.GENL_ID_CTRL,
-                        Netlink.NLM_F_REQUEST | Netlink.NLM_F_ACK | Netlink.NLM_F_DUMP,
-                        Netlink.CTRL_CMD_GETFAMILY, 1)
-        msg = _genl_msg_finalize(msg)
-
-        sock.send(msg, 0)
-
-        global genl_family_name_to_id
-        genl_family_name_to_id = dict()
-
-        while True:
-            reply = sock.recv(128 * 1024)
-            nms = NlMsgs(reply)
-            for nl_msg in nms:
-                if nl_msg.error:
-                    print("Netlink error:", nl_msg.error)
-                    return
-                if nl_msg.done:
-                    return
-
-                gm = GenlMsg(nl_msg)
-                fam = dict()
-                for attr in gm.raw_attrs:
-                    if attr.type == Netlink.CTRL_ATTR_FAMILY_ID:
-                        fam['id'] = attr.as_u16()
-                    elif attr.type == Netlink.CTRL_ATTR_FAMILY_NAME:
-                        fam['name'] = attr.as_strz()
-                    elif attr.type == Netlink.CTRL_ATTR_MAXATTR:
-                        fam['maxattr'] = attr.as_u32()
-                    elif attr.type == Netlink.CTRL_ATTR_MCAST_GROUPS:
-                        fam['mcast'] = dict()
-                        for entry in NlAttrs(attr.raw):
-                            mcast_name = None
-                            mcast_id = None
-                            for entry_attr in NlAttrs(entry.raw):
-                                if entry_attr.type == Netlink.CTRL_ATTR_MCAST_GRP_NAME:
-                                    mcast_name = entry_attr.as_strz()
-                                elif entry_attr.type == Netlink.CTRL_ATTR_MCAST_GRP_ID:
-                                    mcast_id = entry_attr.as_u32()
-                            if mcast_name and mcast_id is not None:
-                                fam['mcast'][mcast_name] = mcast_id
-                if 'name' in fam and 'id' in fam:
-                    genl_family_name_to_id[fam['name']] = fam
-
-
-class GenlMsg:
-    def __init__(self, nl_msg):
-        self.nl = nl_msg
-
-        self.hdr = nl_msg.raw[0:4]
-        self.raw = nl_msg.raw[4:]
-
-        self.genl_cmd, self.genl_version, _ = struct.unpack("bbH", self.hdr)
-
-        self.raw_attrs = NlAttrs(self.raw)
-
-    def __repr__(self):
-        msg = repr(self.nl)
-        msg += f"\tgenl_cmd = {self.genl_cmd} genl_ver = {self.genl_version}\n"
-        for a in self.raw_attrs:
-            msg += '\t\t' + repr(a) + '\n'
-        return msg
-
-
-class GenlFamily:
-    def __init__(self, family_name):
-        self.family_name = family_name
-
-        global genl_family_name_to_id
-        if genl_family_name_to_id is None:
-            _genl_load_families()
-
-        self.genl_family = genl_family_name_to_id[family_name]
-        self.family_id = genl_family_name_to_id[family_name]['id']
-
-
-#
-# YNL implementation details.
-#
-
-
-class YnlAttrSpace:
-    def __init__(self, family, yaml):
-        self.yaml = yaml
-
-        self.attrs = dict()
-        self.name = self.yaml['name']
-        self.subspace_of = self.yaml['subset-of'] if 'subspace-of' in self.yaml else None
-
-        val = 0
-        max_val = 0
-        for elem in self.yaml['attributes']:
-            if 'value' in elem:
-                val = elem['value']
-            else:
-                elem['value'] = val
-            if val > max_val:
-                max_val = val
-            val += 1
-
-            self.attrs[elem['name']] = elem
-
-        self.attr_list = [None] * (max_val + 1)
-        for elem in self.yaml['attributes']:
-            self.attr_list[elem['value']] = elem
-
-    def __getitem__(self, key):
-        return self.attrs[key]
-
-    def __contains__(self, key):
-        return key in self.yaml
-
-    def __iter__(self):
-        yield from self.attrs
-
-    def items(self):
-        return self.attrs.items()
-
-
-class YnlFamily:
-    def __init__(self, def_path, schema=None):
-        self.include_raw = False
-
-        with open(def_path, "r") as stream:
-            self.yaml = yaml.safe_load(stream)
-
-        if schema:
-            with open(schema, "r") as stream:
-                schema = yaml.safe_load(stream)
-
-            jsonschema.validate(self.yaml, schema)
-
-        self.sock = socket.socket(socket.AF_NETLINK, socket.SOCK_RAW, Netlink.NETLINK_GENERIC)
-        self.sock.setsockopt(Netlink.SOL_NETLINK, Netlink.NETLINK_CAP_ACK, 1)
-        self.sock.setsockopt(Netlink.SOL_NETLINK, Netlink.NETLINK_EXT_ACK, 1)
-
-        self._ops = dict()
-        self._spaces = dict()
-        self._types = dict()
-
-        for elem in self.yaml['attribute-sets']:
-            self._spaces[elem['name']] = YnlAttrSpace(self, elem)
-
-        for elem in self.yaml['definitions']:
-            self._types[elem['name']] = elem
-
-        async_separation = 'async-prefix' in self.yaml['operations']
-        self.async_msg_ids = set()
-        self.async_msg_queue = []
-        val = 0
-        max_val = 0
-        for elem in self.yaml['operations']['list']:
-            if not (async_separation and ('notify' in elem or 'event' in elem)):
-                if 'value' in elem:
-                    val = elem['value']
-                else:
-                    elem['value'] = val
-                val += 1
-                max_val = max(val, max_val)
-
-            if 'notify' in elem or 'event' in elem:
-                self.async_msg_ids.add(elem['value'])
-
-            self._ops[elem['name']] = elem
-
-            op_name = elem['name'].replace('-', '_')
-
-            bound_f = functools.partial(self._op, elem['name'])
-            setattr(self, op_name, bound_f)
-
-        self._op_array = [None] * max_val
-        for _, op in self._ops.items():
-            self._op_array[op['value']] = op
-            if 'notify' in op:
-                op['attribute-set'] = self._ops[op['notify']]['attribute-set']
-
-        self.family = GenlFamily(self.yaml['name'])
-
-    def ntf_subscribe(self, mcast_name):
-        if mcast_name not in self.family.genl_family['mcast']:
-            raise Exception(f'Multicast group "{mcast_name}" not present in the family')
-
-        self.sock.bind((0, 0))
-        self.sock.setsockopt(Netlink.SOL_NETLINK, Netlink.NETLINK_ADD_MEMBERSHIP,
-                             self.family.genl_family['mcast'][mcast_name])
-
-    def _add_attr(self, space, name, value):
-        attr = self._spaces[space][name]
-        nl_type = attr['value']
-        if attr["type"] == 'nest':
-            nl_type |= Netlink.NLA_F_NESTED
-            attr_payload = b''
-            for subname, subvalue in value.items():
-                attr_payload += self._add_attr(attr['nested-attributes'], subname, subvalue)
-        elif attr["type"] == 'u32':
-            attr_payload = struct.pack("I", int(value))
-        elif attr["type"] == 'string':
-            attr_payload = str(value).encode('ascii') + b'\x00'
-        elif attr["type"] == 'binary':
-            attr_payload = value
-        else:
-            raise Exception(f'Unknown type at {space} {name} {value} {attr["type"]}')
-
-        pad = b'\x00' * ((4 - len(attr_payload) % 4) % 4)
-        return struct.pack('HH', len(attr_payload) + 4, nl_type) + attr_payload + pad
-
-    def _decode_enum(self, rsp, attr_spec):
-        raw = rsp[attr_spec['name']]
-        enum = self._types[attr_spec['enum']]
-        i = attr_spec.get('value-start', 0)
-        if 'enum-as-flags' in attr_spec and attr_spec['enum-as-flags']:
-            value = set()
-            while raw:
-                if raw & 1:
-                    value.add(enum['entries'][i])
-                raw >>= 1
-                i += 1
-        else:
-            value = enum['entries'][raw - i]
-        rsp[attr_spec['name']] = value
-
-    def _decode(self, attrs, space):
-        attr_space = self._spaces[space]
-        rsp = dict()
-        for attr in attrs:
-            attr_spec = attr_space.attr_list[attr.type]
-            if attr_spec["type"] == 'nest':
-                subdict = self._decode(NlAttrs(attr.raw), attr_spec['nested-attributes'])
-                rsp[attr_spec['name']] = subdict
-            elif attr_spec['type'] == 'u32':
-                rsp[attr_spec['name']] = attr.as_u32()
-            elif attr_spec['type'] == 'u64':
-                rsp[attr_spec['name']] = attr.as_u64()
-            elif attr_spec["type"] == 'string':
-                rsp[attr_spec['name']] = attr.as_strz()
-            elif attr_spec["type"] == 'binary':
-                rsp[attr_spec['name']] = attr.as_bin()
-            else:
-                raise Exception(f'Unknown {attr.type} {attr_spec["name"]} {attr_spec["type"]}')
-
-            if 'enum' in attr_spec:
-                self._decode_enum(rsp, attr_spec)
-        return rsp
-
-    def handle_ntf(self, nl_msg, genl_msg):
-        msg = dict()
-        if self.include_raw:
-            msg['nlmsg'] = nl_msg
-            msg['genlmsg'] = genl_msg
-        op = self._op_array[genl_msg.genl_cmd]
-        msg['name'] = op['name']
-        msg['msg'] = self._decode(genl_msg.raw_attrs, op['attribute-set'])
-        self.async_msg_queue.append(msg)
-
-    def check_ntf(self):
-        while True:
-            try:
-                reply = self.sock.recv(128 * 1024, socket.MSG_DONTWAIT)
-            except BlockingIOError:
-                return
-
-            nms = NlMsgs(reply)
-            for nl_msg in nms:
-                if nl_msg.error:
-                    print("Netlink error in ntf!?", os.strerror(-nl_msg.error))
-                    print(nl_msg)
-                    continue
-                if nl_msg.done:
-                    print("Netlink done while checking for ntf!?")
-                    continue
-
-                gm = GenlMsg(nl_msg)
-                if gm.genl_cmd not in self.async_msg_ids:
-                    print("Unexpected msg id done while checking for ntf", gm)
-                    continue
-
-                self.handle_ntf(nl_msg, gm)
-
-    def _op(self, method, vals, dump=False):
-        op = self._ops[method]
-
-        nl_flags = Netlink.NLM_F_REQUEST | Netlink.NLM_F_ACK
-        if dump:
-            nl_flags |= Netlink.NLM_F_DUMP
-
-        req_seq = random.randint(1024, 65535)
-        msg = _genl_msg(self.family.family_id, nl_flags, op['value'], 1, req_seq)
-        for name, value in vals.items():
-            msg += self._add_attr(op['attribute-set'], name, value)
-        msg = _genl_msg_finalize(msg)
-
-        self.sock.send(msg, 0)
-
-        done = False
-        rsp = []
-        while not done:
-            reply = self.sock.recv(128 * 1024)
-            nms = NlMsgs(reply, attr_space=self._spaces[op['attribute-set']])
-            for nl_msg in nms:
-                if nl_msg.error:
-                    print("Netlink error:", os.strerror(-nl_msg.error))
-                    print(nl_msg)
-                    return
-                if nl_msg.done:
-                    done = True
-                    break
-
-                gm = GenlMsg(nl_msg)
-                # Check if this is a reply to our request
-                if nl_msg.nl_seq != req_seq or gm.genl_cmd != op['value']:
-                    if gm.genl_cmd in self.async_msg_ids:
-                        self.handle_ntf(nl_msg, gm)
-                        continue
-                    else:
-                        print('Unexpected message: ' + repr(gm))
-                        continue
-
-                rsp.append(self._decode(gm.raw_attrs, op['attribute-set']))
-
-        if not rsp:
-            return None
-        if not dump and len(rsp) == 1:
-            return rsp[0]
-        return rsp