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-rw-r--r--tools/net/ynl/lib/nlspec.py545
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diff --git a/tools/net/ynl/lib/nlspec.py b/tools/net/ynl/lib/nlspec.py
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+# SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
+
+import collections
+import importlib
+import os
+import yaml
+
+
+# To be loaded dynamically as needed
+jsonschema = None
+
+
+class SpecElement:
+ """Netlink spec element.
+
+ Abstract element of the Netlink spec. Implements the dictionary interface
+ for access to the raw spec. Supports iterative resolution of dependencies
+ across elements and class inheritance levels. The elements of the spec
+ may refer to each other, and although loops should be very rare, having
+ to maintain correct ordering of instantiation is painful, so the resolve()
+ method should be used to perform parts of init which require access to
+ other parts of the spec.
+
+ Attributes:
+ yaml raw spec as loaded from the spec file
+ family back reference to the full family
+
+ name name of the entity as listed in the spec (optional)
+ ident_name name which can be safely used as identifier in code (optional)
+ """
+ def __init__(self, family, yaml):
+ self.yaml = yaml
+ self.family = family
+
+ if 'name' in self.yaml:
+ self.name = self.yaml['name']
+ self.ident_name = self.name.replace('-', '_')
+
+ self._super_resolved = False
+ family.add_unresolved(self)
+
+ def __getitem__(self, key):
+ return self.yaml[key]
+
+ def __contains__(self, key):
+ return key in self.yaml
+
+ def get(self, key, default=None):
+ return self.yaml.get(key, default)
+
+ def resolve_up(self, up):
+ if not self._super_resolved:
+ up.resolve()
+ self._super_resolved = True
+
+ def resolve(self):
+ pass
+
+
+class SpecEnumEntry(SpecElement):
+ """ Entry within an enum declared in the Netlink spec.
+
+ Attributes:
+ doc documentation string
+ enum_set back reference to the enum
+ value numerical value of this enum (use accessors in most situations!)
+
+ Methods:
+ raw_value raw value, i.e. the id in the enum, unlike user value which is a mask for flags
+ user_value user value, same as raw value for enums, for flags it's the mask
+ """
+ def __init__(self, enum_set, yaml, prev, value_start):
+ if isinstance(yaml, str):
+ yaml = {'name': yaml}
+ super().__init__(enum_set.family, yaml)
+
+ self.doc = yaml.get('doc', '')
+ self.enum_set = enum_set
+
+ if 'value' in yaml:
+ self.value = yaml['value']
+ elif prev:
+ self.value = prev.value + 1
+ else:
+ self.value = value_start
+
+ def has_doc(self):
+ return bool(self.doc)
+
+ def raw_value(self):
+ return self.value
+
+ def user_value(self, as_flags=None):
+ if self.enum_set['type'] == 'flags' or as_flags:
+ return 1 << self.value
+ else:
+ return self.value
+
+
+class SpecEnumSet(SpecElement):
+ """ Enum type
+
+ Represents an enumeration (list of numerical constants)
+ as declared in the "definitions" section of the spec.
+
+ Attributes:
+ type enum or flags
+ entries entries by name
+ entries_by_val entries by value
+ Methods:
+ get_mask for flags compute the mask of all defined values
+ """
+ def __init__(self, family, yaml):
+ super().__init__(family, yaml)
+
+ self.type = yaml['type']
+
+ prev_entry = None
+ value_start = self.yaml.get('value-start', 0)
+ self.entries = dict()
+ self.entries_by_val = dict()
+ for entry in self.yaml['entries']:
+ e = self.new_entry(entry, prev_entry, value_start)
+ self.entries[e.name] = e
+ self.entries_by_val[e.raw_value()] = e
+ prev_entry = e
+
+ def new_entry(self, entry, prev_entry, value_start):
+ return SpecEnumEntry(self, entry, prev_entry, value_start)
+
+ def has_doc(self):
+ if 'doc' in self.yaml:
+ return True
+ for entry in self.entries.values():
+ if entry.has_doc():
+ return True
+ return False
+
+ def get_mask(self, as_flags=None):
+ mask = 0
+ for e in self.entries.values():
+ mask += e.user_value(as_flags)
+ return mask
+
+
+class SpecAttr(SpecElement):
+ """ Single Netlink atttribute type
+
+ Represents a single attribute type within an attr space.
+
+ Attributes:
+ value numerical ID when serialized
+ attr_set Attribute Set containing this attr
+ is_multi bool, attr may repeat multiple times
+ struct_name string, name of struct definition
+ sub_type string, name of sub type
+ len integer, optional byte length of binary types
+ display_hint string, hint to help choose format specifier
+ when displaying the value
+ """
+ def __init__(self, family, attr_set, yaml, value):
+ super().__init__(family, yaml)
+
+ self.value = value
+ self.attr_set = attr_set
+ self.is_multi = yaml.get('multi-attr', False)
+ self.struct_name = yaml.get('struct')
+ self.sub_type = yaml.get('sub-type')
+ self.byte_order = yaml.get('byte-order')
+ self.len = yaml.get('len')
+ self.display_hint = yaml.get('display-hint')
+
+
+class SpecAttrSet(SpecElement):
+ """ Netlink Attribute Set class.
+
+ Represents a ID space of attributes within Netlink.
+
+ Note that unlike other elements, which expose contents of the raw spec
+ via the dictionary interface Attribute Set exposes attributes by name.
+
+ Attributes:
+ attrs ordered dict of all attributes (indexed by name)
+ attrs_by_val ordered dict of all attributes (indexed by value)
+ subset_of parent set if this is a subset, otherwise None
+ """
+ def __init__(self, family, yaml):
+ super().__init__(family, yaml)
+
+ self.subset_of = self.yaml.get('subset-of', None)
+
+ self.attrs = collections.OrderedDict()
+ self.attrs_by_val = collections.OrderedDict()
+
+ if self.subset_of is None:
+ val = 1
+ for elem in self.yaml['attributes']:
+ if 'value' in elem:
+ val = elem['value']
+
+ attr = self.new_attr(elem, val)
+ self.attrs[attr.name] = attr
+ self.attrs_by_val[attr.value] = attr
+ val += 1
+ else:
+ real_set = family.attr_sets[self.subset_of]
+ for elem in self.yaml['attributes']:
+ attr = real_set[elem['name']]
+ self.attrs[attr.name] = attr
+ self.attrs_by_val[attr.value] = attr
+
+ def new_attr(self, elem, value):
+ return SpecAttr(self.family, self, elem, value)
+
+ def __getitem__(self, key):
+ return self.attrs[key]
+
+ def __contains__(self, key):
+ return key in self.attrs
+
+ def __iter__(self):
+ yield from self.attrs
+
+ def items(self):
+ return self.attrs.items()
+
+
+class SpecStructMember(SpecElement):
+ """Struct member attribute
+
+ Represents a single struct member attribute.
+
+ Attributes:
+ type string, type of the member attribute
+ byte_order string or None for native byte order
+ enum string, name of the enum definition
+ len integer, optional byte length of binary types
+ display_hint string, hint to help choose format specifier
+ when displaying the value
+ """
+ def __init__(self, family, yaml):
+ super().__init__(family, yaml)
+ self.type = yaml['type']
+ self.byte_order = yaml.get('byte-order')
+ self.enum = yaml.get('enum')
+ self.len = yaml.get('len')
+ self.display_hint = yaml.get('display-hint')
+
+
+class SpecStruct(SpecElement):
+ """Netlink struct type
+
+ Represents a C struct definition.
+
+ Attributes:
+ members ordered list of struct members
+ """
+ def __init__(self, family, yaml):
+ super().__init__(family, yaml)
+
+ self.members = []
+ for member in yaml.get('members', []):
+ self.members.append(self.new_member(family, member))
+
+ def new_member(self, family, elem):
+ return SpecStructMember(family, elem)
+
+ def __iter__(self):
+ yield from self.members
+
+ def items(self):
+ return self.members.items()
+
+
+class SpecOperation(SpecElement):
+ """Netlink Operation
+
+ Information about a single Netlink operation.
+
+ Attributes:
+ value numerical ID when serialized, None if req/rsp values differ
+
+ req_value numerical ID when serialized, user -> kernel
+ rsp_value numerical ID when serialized, user <- kernel
+ is_call bool, whether the operation is a call
+ is_async bool, whether the operation is a notification
+ is_resv bool, whether the operation does not exist (it's just a reserved ID)
+ attr_set attribute set name
+ fixed_header string, optional name of fixed header struct
+
+ yaml raw spec as loaded from the spec file
+ """
+ def __init__(self, family, yaml, req_value, rsp_value):
+ super().__init__(family, yaml)
+
+ self.value = req_value if req_value == rsp_value else None
+ self.req_value = req_value
+ self.rsp_value = rsp_value
+
+ self.is_call = 'do' in yaml or 'dump' in yaml
+ self.is_async = 'notify' in yaml or 'event' in yaml
+ self.is_resv = not self.is_async and not self.is_call
+ self.fixed_header = self.yaml.get('fixed-header', family.fixed_header)
+
+ # Added by resolve:
+ self.attr_set = None
+ delattr(self, "attr_set")
+
+ def resolve(self):
+ self.resolve_up(super())
+
+ if 'attribute-set' in self.yaml:
+ attr_set_name = self.yaml['attribute-set']
+ elif 'notify' in self.yaml:
+ msg = self.family.msgs[self.yaml['notify']]
+ attr_set_name = msg['attribute-set']
+ elif self.is_resv:
+ attr_set_name = ''
+ else:
+ raise Exception(f"Can't resolve attribute set for op '{self.name}'")
+ if attr_set_name:
+ self.attr_set = self.family.attr_sets[attr_set_name]
+
+
+class SpecMcastGroup(SpecElement):
+ """Netlink Multicast Group
+
+ Information about a multicast group.
+
+ Value is only used for classic netlink families that use the
+ netlink-raw schema. Genetlink families use dynamic ID allocation
+ where the ids of multicast groups get resolved at runtime. Value
+ will be None for genetlink families.
+
+ Attributes:
+ name name of the mulitcast group
+ value integer id of this multicast group for netlink-raw or None
+ yaml raw spec as loaded from the spec file
+ """
+ def __init__(self, family, yaml):
+ super().__init__(family, yaml)
+ self.value = self.yaml.get('value')
+
+
+class SpecFamily(SpecElement):
+ """ Netlink Family Spec class.
+
+ Netlink family information loaded from a spec (e.g. in YAML).
+ Takes care of unfolding implicit information which can be skipped
+ in the spec itself for brevity.
+
+ The class can be used like a dictionary to access the raw spec
+ elements but that's usually a bad idea.
+
+ Attributes:
+ proto protocol type (e.g. genetlink)
+ msg_id_model enum-model for operations (unified, directional etc.)
+ license spec license (loaded from an SPDX tag on the spec)
+
+ attr_sets dict of attribute sets
+ msgs dict of all messages (index by name)
+ ops dict of all valid requests / responses
+ ntfs dict of all async events
+ consts dict of all constants/enums
+ fixed_header string, optional name of family default fixed header struct
+ mcast_groups dict of all multicast groups (index by name)
+ """
+ def __init__(self, spec_path, schema_path=None, exclude_ops=None):
+ with open(spec_path, "r") as stream:
+ prefix = '# SPDX-License-Identifier: '
+ first = stream.readline().strip()
+ if not first.startswith(prefix):
+ raise Exception('SPDX license tag required in the spec')
+ self.license = first[len(prefix):]
+
+ stream.seek(0)
+ spec = yaml.safe_load(stream)
+
+ self._resolution_list = []
+
+ super().__init__(self, spec)
+
+ self._exclude_ops = exclude_ops if exclude_ops else []
+
+ self.proto = self.yaml.get('protocol', 'genetlink')
+ self.msg_id_model = self.yaml['operations'].get('enum-model', 'unified')
+
+ if schema_path is None:
+ schema_path = os.path.dirname(os.path.dirname(spec_path)) + f'/{self.proto}.yaml'
+ if schema_path:
+ global jsonschema
+
+ with open(schema_path, "r") as stream:
+ schema = yaml.safe_load(stream)
+
+ if jsonschema is None:
+ jsonschema = importlib.import_module("jsonschema")
+
+ jsonschema.validate(self.yaml, schema)
+
+ self.attr_sets = collections.OrderedDict()
+ self.msgs = collections.OrderedDict()
+ self.req_by_value = collections.OrderedDict()
+ self.rsp_by_value = collections.OrderedDict()
+ self.ops = collections.OrderedDict()
+ self.ntfs = collections.OrderedDict()
+ self.consts = collections.OrderedDict()
+ self.mcast_groups = collections.OrderedDict()
+
+ last_exception = None
+ while len(self._resolution_list) > 0:
+ resolved = []
+ unresolved = self._resolution_list
+ self._resolution_list = []
+
+ for elem in unresolved:
+ try:
+ elem.resolve()
+ except (KeyError, AttributeError) as e:
+ self._resolution_list.append(elem)
+ last_exception = e
+ continue
+
+ resolved.append(elem)
+
+ if len(resolved) == 0:
+ raise last_exception
+
+ def new_enum(self, elem):
+ return SpecEnumSet(self, elem)
+
+ def new_attr_set(self, elem):
+ return SpecAttrSet(self, elem)
+
+ def new_struct(self, elem):
+ return SpecStruct(self, elem)
+
+ def new_operation(self, elem, req_val, rsp_val):
+ return SpecOperation(self, elem, req_val, rsp_val)
+
+ def new_mcast_group(self, elem):
+ return SpecMcastGroup(self, elem)
+
+ def add_unresolved(self, elem):
+ self._resolution_list.append(elem)
+
+ def _dictify_ops_unified(self):
+ self.fixed_header = self.yaml['operations'].get('fixed-header')
+ val = 1
+ for elem in self.yaml['operations']['list']:
+ if 'value' in elem:
+ val = elem['value']
+
+ op = self.new_operation(elem, val, val)
+ val += 1
+
+ self.msgs[op.name] = op
+
+ def _dictify_ops_directional(self):
+ self.fixed_header = self.yaml['operations'].get('fixed-header')
+ req_val = rsp_val = 1
+ for elem in self.yaml['operations']['list']:
+ if 'notify' in elem or 'event' in elem:
+ if 'value' in elem:
+ rsp_val = elem['value']
+ req_val_next = req_val
+ rsp_val_next = rsp_val + 1
+ req_val = None
+ elif 'do' in elem or 'dump' in elem:
+ mode = elem['do'] if 'do' in elem else elem['dump']
+
+ v = mode.get('request', {}).get('value', None)
+ if v:
+ req_val = v
+ v = mode.get('reply', {}).get('value', None)
+ if v:
+ rsp_val = v
+
+ rsp_inc = 1 if 'reply' in mode else 0
+ req_val_next = req_val + 1
+ rsp_val_next = rsp_val + rsp_inc
+ else:
+ raise Exception("Can't parse directional ops")
+
+ if req_val == req_val_next:
+ req_val = None
+ if rsp_val == rsp_val_next:
+ rsp_val = None
+
+ skip = False
+ for exclude in self._exclude_ops:
+ skip |= bool(exclude.match(elem['name']))
+ if not skip:
+ op = self.new_operation(elem, req_val, rsp_val)
+
+ req_val = req_val_next
+ rsp_val = rsp_val_next
+
+ self.msgs[op.name] = op
+
+ def find_operation(self, name):
+ """
+ For a given operation name, find and return operation spec.
+ """
+ for op in self.yaml['operations']['list']:
+ if name == op['name']:
+ return op
+ return None
+
+ def resolve(self):
+ self.resolve_up(super())
+
+ definitions = self.yaml.get('definitions', [])
+ for elem in definitions:
+ if elem['type'] == 'enum' or elem['type'] == 'flags':
+ self.consts[elem['name']] = self.new_enum(elem)
+ elif elem['type'] == 'struct':
+ self.consts[elem['name']] = self.new_struct(elem)
+ else:
+ self.consts[elem['name']] = elem
+
+ for elem in self.yaml['attribute-sets']:
+ attr_set = self.new_attr_set(elem)
+ self.attr_sets[elem['name']] = attr_set
+
+ if self.msg_id_model == 'unified':
+ self._dictify_ops_unified()
+ elif self.msg_id_model == 'directional':
+ self._dictify_ops_directional()
+
+ for op in self.msgs.values():
+ if op.req_value is not None:
+ self.req_by_value[op.req_value] = op
+ if op.rsp_value is not None:
+ self.rsp_by_value[op.rsp_value] = op
+ if not op.is_async and 'attribute-set' in op:
+ self.ops[op.name] = op
+ elif op.is_async:
+ self.ntfs[op.name] = op
+
+ mcgs = self.yaml.get('mcast-groups')
+ if mcgs:
+ for elem in mcgs['list']:
+ mcg = self.new_mcast_group(elem)
+ self.mcast_groups[elem['name']] = mcg