diff options
Diffstat (limited to 'tools/net/ynl/lib/ynl.py')
| -rw-r--r-- | tools/net/ynl/lib/ynl.py | 61 |
1 files changed, 54 insertions, 7 deletions
diff --git a/tools/net/ynl/lib/ynl.py b/tools/net/ynl/lib/ynl.py index ac55aa5a3083..2d7fdd903d9e 100644 --- a/tools/net/ynl/lib/ynl.py +++ b/tools/net/ynl/lib/ynl.py @@ -7,6 +7,7 @@ import random import socket import struct from struct import Struct +import sys import yaml import ipaddress import uuid @@ -84,6 +85,10 @@ class NlError(Exception): return f"Netlink error: {os.strerror(-self.nl_msg.error)}\n{self.nl_msg}" +class ConfigError(Exception): + pass + + class NlAttr: ScalarFormat = namedtuple('ScalarFormat', ['native', 'big', 'little']) type_formats = { @@ -213,11 +218,11 @@ class NlMsg: return self.nl_type 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" + msg = f"nl_len = {self.nl_len} ({len(self.raw)}) nl_flags = 0x{self.nl_flags:x} nl_type = {self.nl_type}" if self.error: - msg += '\terror: ' + str(self.error) + msg += '\n\terror: ' + str(self.error) if self.extack: - msg += '\textack: ' + repr(self.extack) + msg += '\n\textack: ' + repr(self.extack) return msg @@ -348,6 +353,9 @@ class NetlinkProtocol: raise Exception(f'Multicast group "{mcast_name}" not present in the spec') return mcast_groups[mcast_name].value + def msghdr_size(self): + return 16 + class GenlProtocol(NetlinkProtocol): def __init__(self, family_name): @@ -373,6 +381,8 @@ class GenlProtocol(NetlinkProtocol): raise Exception(f'Multicast group "{mcast_name}" not present in the family') return self.genl_family['mcast'][mcast_name] + def msghdr_size(self): + return super().msghdr_size() + 4 class SpaceAttrs: @@ -400,7 +410,8 @@ class SpaceAttrs: class YnlFamily(SpecFamily): - def __init__(self, def_path, schema=None, process_unknown=False): + def __init__(self, def_path, schema=None, process_unknown=False, + recv_size=0): super().__init__(def_path, schema) self.include_raw = False @@ -415,6 +426,17 @@ class YnlFamily(SpecFamily): except KeyError: raise Exception(f"Family '{self.yaml['name']}' not supported by the kernel") + self._recv_dbg = False + # Note that netlink will use conservative (min) message size for + # the first dump recv() on the socket, our setting will only matter + # from the second recv() on. + self._recv_size = recv_size if recv_size else 131072 + # Netlink will always allocate at least PAGE_SIZE - sizeof(skb_shinfo) + # for a message, so smaller receive sizes will lead to truncation. + # Note that the min size for other families may be larger than 4k! + if self._recv_size < 4000: + raise ConfigError() + self.sock = socket.socket(socket.AF_NETLINK, socket.SOCK_RAW, self.nlproto.proto_num) self.sock.setsockopt(Netlink.SOL_NETLINK, Netlink.NETLINK_CAP_ACK, 1) self.sock.setsockopt(Netlink.SOL_NETLINK, Netlink.NETLINK_EXT_ACK, 1) @@ -438,6 +460,17 @@ class YnlFamily(SpecFamily): self.sock.setsockopt(Netlink.SOL_NETLINK, Netlink.NETLINK_ADD_MEMBERSHIP, mcast_id) + def set_recv_dbg(self, enabled): + self._recv_dbg = enabled + + def _recv_dbg_print(self, reply, nl_msgs): + if not self._recv_dbg: + return + print("Recv: read", len(reply), "bytes,", + len(nl_msgs.msgs), "messages", file=sys.stderr) + for nl_msg in nl_msgs: + print(" ", nl_msg, file=sys.stderr) + def _encode_enum(self, attr_spec, value): enum = self.consts[attr_spec['enum']] if enum.type == 'flags' or attr_spec.get('enum-as-flags', False): @@ -562,6 +595,16 @@ class YnlFamily(SpecFamily): decoded.append({ item.type: subattrs }) return decoded + def _decode_nest_type_value(self, attr, attr_spec): + decoded = {} + value = attr + for name in attr_spec['type-value']: + value = NlAttr(value.raw, 0) + decoded[name] = value.type + subattrs = self._decode(NlAttrs(value.raw), attr_spec['nested-attributes']) + decoded.update(subattrs) + return decoded + def _decode_unknown(self, attr): if attr.is_nest: return self._decode(NlAttrs(attr.raw), None) @@ -653,6 +696,8 @@ class YnlFamily(SpecFamily): decoded = {"value": value, "selector": selector} elif attr_spec["type"] == 'sub-message': decoded = self._decode_sub_msg(attr, attr_spec, search_attrs) + elif attr_spec["type"] == 'nest-type-value': + decoded = self._decode_nest_type_value(attr, attr_spec) else: if not self.process_unknown: raise Exception(f'Unknown {attr_spec["type"]} with name {attr_spec["name"]}') @@ -693,7 +738,7 @@ class YnlFamily(SpecFamily): return msg = self.nlproto.decode(self, NlMsg(request, 0, op.attr_set)) - offset = 20 + self._struct_size(op.fixed_header) + offset = self.nlproto.msghdr_size() + self._struct_size(op.fixed_header) path = self._decode_extack_path(msg.raw_attrs, op.attr_set, offset, extack['bad-attr-offs']) if path: @@ -799,11 +844,12 @@ class YnlFamily(SpecFamily): def check_ntf(self): while True: try: - reply = self.sock.recv(128 * 1024, socket.MSG_DONTWAIT) + reply = self.sock.recv(self._recv_size, socket.MSG_DONTWAIT) except BlockingIOError: return nms = NlMsgs(reply) + self._recv_dbg_print(reply, nms) for nl_msg in nms: if nl_msg.error: print("Netlink error in ntf!?", os.strerror(-nl_msg.error)) @@ -854,8 +900,9 @@ class YnlFamily(SpecFamily): done = False rsp = [] while not done: - reply = self.sock.recv(128 * 1024) + reply = self.sock.recv(self._recv_size) nms = NlMsgs(reply, attr_space=op.attr_set) + self._recv_dbg_print(reply, nms) for nl_msg in nms: if nl_msg.extack: self._decode_extack(msg, op, nl_msg.extack) |