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 | 
