diff options
Diffstat (limited to 'tools/net/ynl/lib/ynl.py')
-rw-r--r-- | tools/net/ynl/lib/ynl.py | 120 |
1 files changed, 102 insertions, 18 deletions
diff --git a/tools/net/ynl/lib/ynl.py b/tools/net/ynl/lib/ynl.py index 32536e1f9064..aa77bcae4807 100644 --- a/tools/net/ynl/lib/ynl.py +++ b/tools/net/ynl/lib/ynl.py @@ -67,7 +67,20 @@ class Netlink: NLMSGERR_ATTR_MISS_NEST = 6 +class NlError(Exception): + def __init__(self, nl_msg): + self.nl_msg = nl_msg + + def __str__(self): + return f"Netlink error: {os.strerror(-self.nl_msg.error)}\n{self.nl_msg}" + + 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) } + def __init__(self, raw, offset): self._len, self._type = struct.unpack("HH", raw[offset:offset + 4]) self.type = self._type & ~Netlink.NLA_TYPE_MASK @@ -75,17 +88,25 @@ class NlAttr: self.full_len = (self.payload_len + 3) & ~3 self.raw = raw[offset + 4:offset + self.payload_len] + def format_byte_order(byte_order): + if byte_order: + return ">" if byte_order == "big-endian" else "<" + return "" + def as_u8(self): return struct.unpack("B", self.raw)[0] - def as_u16(self): - return struct.unpack("H", 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): - return struct.unpack("I", 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): - return struct.unpack("Q", 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_strz(self): return self.raw.decode('ascii')[:-1] @@ -93,6 +114,21 @@ class NlAttr: def as_bin(self): 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) }) + + 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 + value[m.name] = decoded[0] + return value + def __repr__(self): return f"[type:{self.type} len:{self._len}] {self.raw}" @@ -258,14 +294,22 @@ def _genl_load_families(): class GenlMsg: - def __init__(self, nl_msg): + def __init__(self, nl_msg, fixed_header_members=[]): self.nl = nl_msg self.hdr = nl_msg.raw[0:4] - self.raw = nl_msg.raw[4:] + offset = 4 self.genl_cmd, self.genl_version, _ = struct.unpack("BBH", self.hdr) + 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 + self.fixed_header_attrs[m.name] = decoded[0] + + self.raw = nl_msg.raw[offset:] self.raw_attrs = NlAttrs(self.raw) def __repr__(self): @@ -314,7 +358,10 @@ class YnlFamily(SpecFamily): bound_f = functools.partial(self._op, op_name) setattr(self, op.ident_name, bound_f) - self.family = GenlFamily(self.yaml['name']) + try: + self.family = GenlFamily(self.yaml['name']) + except KeyError: + raise Exception(f"Family '{self.yaml['name']}' not supported by the kernel") def ntf_subscribe(self, mcast_name): if mcast_name not in self.family.genl_family['mcast']: @@ -334,8 +381,17 @@ 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': - attr_payload = struct.pack("I", int(value)) + 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': @@ -361,6 +417,15 @@ class YnlFamily(SpecFamily): value = enum.entries_by_val[raw - i].name rsp[attr_spec['name']] = value + def _decode_binary(self, attr, attr_spec): + if attr_spec.struct_name: + decoded = attr.as_struct(self.consts[attr_spec.struct_name]) + elif attr_spec.sub_type: + decoded = attr.as_c_array(attr_spec.sub_type) + else: + decoded = attr.as_bin() + return decoded + def _decode(self, attrs, space): attr_space = self.attr_sets[space] rsp = dict() @@ -371,14 +436,16 @@ class YnlFamily(SpecFamily): 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() + decoded = attr.as_u32(attr_spec.byte_order) elif attr_spec['type'] == 'u64': - decoded = attr.as_u64() + decoded = attr.as_u64(attr_spec.byte_order) elif attr_spec["type"] == 'string': decoded = attr.as_strz() elif attr_spec["type"] == 'binary': - decoded = attr.as_bin() + decoded = self._decode_binary(attr, attr_spec) elif attr_spec["type"] == 'flag': decoded = True else: @@ -463,6 +530,17 @@ class YnlFamily(SpecFamily): self.handle_ntf(nl_msg, gm) + def operation_do_attributes(self, name): + """ + For a given operation name, find and return a supported + set of attributes (as a dict). + """ + op = self.find_operation(name) + if not op: + return None + + return op['do']['request']['attributes'].copy() + def _op(self, method, vals, dump=False): op = self.ops[method] @@ -472,6 +550,13 @@ class YnlFamily(SpecFamily): req_seq = random.randint(1024, 65535) msg = _genl_msg(self.family.family_id, nl_flags, op.req_value, 1, req_seq) + fixed_header_members = [] + if op.fixed_header: + 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) for name, value in vals.items(): msg += self._add_attr(op.attr_set.name, name, value) msg = _genl_msg_finalize(msg) @@ -488,9 +573,7 @@ class YnlFamily(SpecFamily): self._decode_extack(msg, op.attr_set, nl_msg.extack) if nl_msg.error: - print("Netlink error:", os.strerror(-nl_msg.error)) - print(nl_msg) - return + raise NlError(nl_msg) if nl_msg.done: if nl_msg.extack: print("Netlink warning:") @@ -498,7 +581,7 @@ class YnlFamily(SpecFamily): done = True break - gm = GenlMsg(nl_msg) + gm = GenlMsg(nl_msg, fixed_header_members) # Check if this is a reply to our request if nl_msg.nl_seq != req_seq or gm.genl_cmd != op.rsp_value: if gm.genl_cmd in self.async_msg_ids: @@ -508,7 +591,8 @@ class YnlFamily(SpecFamily): print('Unexpected message: ' + repr(gm)) continue - rsp.append(self._decode(gm.raw_attrs, op.attr_set.name)) + rsp.append(self._decode(gm.raw_attrs, op.attr_set.name) + | gm.fixed_header_attrs) if not rsp: return None |