From 7c2435ef76e5f2d9fac44b241e4a54113f6eafbf Mon Sep 17 00:00:00 2001 From: Donald Hunter Date: Tue, 23 May 2023 10:37:47 +0100 Subject: tools: ynl: Use dict of predefined Structs to decode scalar types Use a dict of predefined Struct() objects to decode scalar types in native, big or little endian format. This removes the repetitive code for the scalar variants and ensures all the signed variants are supported. Signed-off-by: Donald Hunter Signed-off-by: David S. Miller --- tools/net/ynl/lib/ynl.py | 101 +++++++++++++++++++++-------------------------- 1 file changed, 44 insertions(+), 57 deletions(-) (limited to 'tools/net/ynl/lib') diff --git a/tools/net/ynl/lib/ynl.py b/tools/net/ynl/lib/ynl.py index aa77bcae4807..6185ba27f2e7 100644 --- a/tools/net/ynl/lib/ynl.py +++ b/tools/net/ynl/lib/ynl.py @@ -1,10 +1,12 @@ # SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause +from collections import namedtuple import functools import os import random import socket import struct +from struct import Struct import yaml from .nlspec import SpecFamily @@ -76,10 +78,17 @@ class NlError(Exception): class NlAttr: - type_formats = { 'u8' : ('B', 1), 's8' : ('b', 1), - 'u16': ('H', 2), 's16': ('h', 2), - 'u32': ('I', 4), 's32': ('i', 4), - 'u64': ('Q', 8), 's64': ('q', 8) } + ScalarFormat = namedtuple('ScalarFormat', ['native', 'big', 'little']) + type_formats = { + 'u8' : ScalarFormat(Struct('B'), Struct("B"), Struct("B")), + 's8' : ScalarFormat(Struct('b'), Struct("b"), Struct("b")), + 'u16': ScalarFormat(Struct('H'), Struct(">H"), Struct("h"), Struct("I"), Struct("i"), Struct("Q"), Struct("q"), Struct("" if byte_order == "big-endian" else "<" - return "" + return format.big if byte_order == "big-endian" \ + else format.little + return format.native - def as_u8(self): - return struct.unpack("B", self.raw)[0] - - def as_u16(self, byte_order=None): - endian = NlAttr.format_byte_order(byte_order) - return struct.unpack(f"{endian}H", self.raw)[0] - - def as_u32(self, byte_order=None): - endian = NlAttr.format_byte_order(byte_order) - return struct.unpack(f"{endian}I", self.raw)[0] - - def as_u64(self, byte_order=None): - endian = NlAttr.format_byte_order(byte_order) - return struct.unpack(f"{endian}Q", self.raw)[0] + def as_scalar(self, attr_type, byte_order=None): + format = self.get_format(attr_type, byte_order) + return format.unpack(self.raw)[0] def as_strz(self): return self.raw.decode('ascii')[:-1] @@ -115,17 +116,17 @@ class NlAttr: return self.raw def as_c_array(self, type): - format, _ = self.type_formats[type] - return list({ x[0] for x in struct.iter_unpack(format, self.raw) }) + format = self.get_format(type) + return [ x[0] for x in format.iter_unpack(self.raw) ] def as_struct(self, members): value = dict() offset = 0 for m in members: # TODO: handle non-scalar members - format, size = self.type_formats[m.type] - decoded = struct.unpack_from(format, self.raw, offset) - offset += size + format = self.get_format(m.type) + decoded = format.unpack_from(self.raw, offset) + offset += format.size value[m.name] = decoded[0] return value @@ -184,11 +185,11 @@ class NlMsg: 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() + self.extack['miss-type'] = extack.as_scalar('u32') elif extack.type == Netlink.NLMSGERR_ATTR_MISS_NEST: - self.extack['miss-nest'] = extack.as_u32() + self.extack['miss-nest'] = extack.as_scalar('u32') elif extack.type == Netlink.NLMSGERR_ATTR_OFFS: - self.extack['bad-attr-offs'] = extack.as_u32() + self.extack['bad-attr-offs'] = extack.as_scalar('u32') else: if 'unknown' not in self.extack: self.extack['unknown'] = [] @@ -272,11 +273,11 @@ def _genl_load_families(): fam = dict() for attr in gm.raw_attrs: if attr.type == Netlink.CTRL_ATTR_FAMILY_ID: - fam['id'] = attr.as_u16() + fam['id'] = attr.as_scalar('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() + fam['maxattr'] = attr.as_scalar('u32') elif attr.type == Netlink.CTRL_ATTR_MCAST_GROUPS: fam['mcast'] = dict() for entry in NlAttrs(attr.raw): @@ -286,7 +287,7 @@ def _genl_load_families(): 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() + mcast_id = entry_attr.as_scalar('u32') if mcast_name and mcast_id is not None: fam['mcast'][mcast_name] = mcast_id if 'name' in fam and 'id' in fam: @@ -304,9 +305,9 @@ class GenlMsg: self.fixed_header_attrs = dict() for m in fixed_header_members: - format, size = NlAttr.type_formats[m.type] - decoded = struct.unpack_from(format, nl_msg.raw, offset) - offset += size + format = NlAttr.get_format(m.type) + decoded = format.unpack_from(nl_msg.raw, offset) + offset += format.size self.fixed_header_attrs[m.name] = decoded[0] self.raw = nl_msg.raw[offset:] @@ -381,21 +382,13 @@ class YnlFamily(SpecFamily): attr_payload += self._add_attr(attr['nested-attributes'], subname, subvalue) elif attr["type"] == 'flag': attr_payload = b'' - elif attr["type"] == 'u8': - attr_payload = struct.pack("B", int(value)) - elif attr["type"] == 'u16': - endian = NlAttr.format_byte_order(attr.byte_order) - attr_payload = struct.pack(f"{endian}H", int(value)) - elif attr["type"] == 'u32': - endian = NlAttr.format_byte_order(attr.byte_order) - attr_payload = struct.pack(f"{endian}I", int(value)) - elif attr["type"] == 'u64': - endian = NlAttr.format_byte_order(attr.byte_order) - attr_payload = struct.pack(f"{endian}Q", int(value)) elif attr["type"] == 'string': attr_payload = str(value).encode('ascii') + b'\x00' elif attr["type"] == 'binary': attr_payload = value + elif attr['type'] in NlAttr.type_formats: + format = NlAttr.get_format(attr['type'], attr.byte_order) + attr_payload = format.pack(int(value)) else: raise Exception(f'Unknown type at {space} {name} {value} {attr["type"]}') @@ -434,22 +427,16 @@ class YnlFamily(SpecFamily): if attr_spec["type"] == 'nest': subdict = self._decode(NlAttrs(attr.raw), attr_spec['nested-attributes']) decoded = subdict - elif attr_spec['type'] == 'u8': - decoded = attr.as_u8() - elif attr_spec['type'] == 'u16': - decoded = attr.as_u16(attr_spec.byte_order) - elif attr_spec['type'] == 'u32': - decoded = attr.as_u32(attr_spec.byte_order) - elif attr_spec['type'] == 'u64': - decoded = attr.as_u64(attr_spec.byte_order) elif attr_spec["type"] == 'string': decoded = attr.as_strz() elif attr_spec["type"] == 'binary': decoded = self._decode_binary(attr, attr_spec) elif attr_spec["type"] == 'flag': decoded = True + elif attr_spec["type"] in NlAttr.type_formats: + decoded = attr.as_scalar(attr_spec['type'], attr_spec.byte_order) else: - raise Exception(f'Unknown {attr.type} {attr_spec["name"]} {attr_spec["type"]}') + raise Exception(f'Unknown {attr_spec["type"]} with name {attr_spec["name"]}') if not attr_spec.is_multi: rsp[attr_spec['name']] = decoded @@ -555,8 +542,8 @@ class YnlFamily(SpecFamily): fixed_header_members = self.consts[op.fixed_header].members for m in fixed_header_members: value = vals.pop(m.name) - format, _ = NlAttr.type_formats[m.type] - msg += struct.pack(format, value) + format = NlAttr.get_format(m.type) + msg += format.pack(value) for name, value in vals.items(): msg += self._add_attr(op.attr_set.name, name, value) msg = _genl_msg_finalize(msg) -- cgit v1.2.3