xref: /linux/Documentation/netlink/netlink-raw.yaml (revision 08df80a3c51674ab73ae770885a383ca553fbbbf)
1# SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)
2%YAML 1.2
3---
4$id: http://kernel.org/schemas/netlink/netlink-raw.yaml#
5$schema: https://json-schema.org/draft-07/schema
6
7# Common defines
8$defs:
9  uint:
10    type: integer
11    minimum: 0
12  len-or-define:
13    type: [ string, integer ]
14    pattern: ^[0-9A-Za-z_]+( - 1)?$
15    minimum: 0
16
17# Schema for specs
18title: Protocol
19description: Specification of a raw netlink protocol
20type: object
21required: [ name, doc, attribute-sets, operations ]
22additionalProperties: False
23properties:
24  name:
25    description: Name of the netlink family.
26    type: string
27  doc:
28    type: string
29  protocol:
30    description: Schema compatibility level.
31    enum: [ netlink-raw ] # Trim
32  # Start netlink-raw
33  protonum:
34    description: Protocol number to use for netlink-raw
35    type: integer
36  # End netlink-raw
37  uapi-header:
38    description: Path to the uAPI header, default is linux/${family-name}.h
39    type: string
40  # Start genetlink-c
41  c-family-name:
42    description: Name of the define for the family name.
43    type: string
44  c-version-name:
45    description: Name of the define for the version of the family.
46    type: string
47  max-by-define:
48    description: Makes the number of attributes and commands be specified by a define, not an enum value.
49    type: boolean
50  cmd-max-name:
51    description: Name of the define for the last operation in the list.
52    type: string
53  cmd-cnt-name:
54    description: The explicit name for constant holding the count of operations (last operation + 1).
55    type: string
56  # End genetlink-c
57  # Start genetlink-legacy
58  kernel-policy:
59    description: |
60      Defines if the input policy in the kernel is global, per-operation, or split per operation type.
61      Default is split.
62    enum: [ split, per-op, global ]
63  # End genetlink-legacy
64
65  definitions:
66    description: List of type and constant definitions (enums, flags, defines).
67    type: array
68    items:
69      type: object
70      required: [ type, name ]
71      additionalProperties: False
72      properties:
73        name:
74          type: string
75        header:
76          description: For C-compatible languages, header which already defines this value.
77          type: string
78        type:
79          enum: [ const, enum, flags, struct ] # Trim
80        doc:
81          type: string
82        # For const
83        value:
84          description: For const - the value.
85          type: [ string, integer ]
86        # For enum and flags
87        value-start:
88          description: For enum or flags the literal initializer for the first value.
89          type: [ string, integer ]
90        entries:
91          description: For enum or flags array of values.
92          type: array
93          items:
94            oneOf:
95              - type: string
96              - type: object
97                required: [ name ]
98                additionalProperties: False
99                properties:
100                  name:
101                    type: string
102                  value:
103                    type: integer
104                  doc:
105                    type: string
106        render-max:
107          description: Render the max members for this enum.
108          type: boolean
109        # Start genetlink-c
110        enum-name:
111          description: Name for enum, if empty no name will be used.
112          type: [ string, "null" ]
113        name-prefix:
114          description: For enum the prefix of the values, optional.
115          type: string
116        # End genetlink-c
117        # Start genetlink-legacy
118        members:
119          description: List of struct members. Only scalars and strings members allowed.
120          type: array
121          items:
122            type: object
123            required: [ name, type ]
124            additionalProperties: False
125            properties:
126              name:
127                type: string
128              type:
129                description: |
130                  The netlink attribute type. Members of type 'binary' or 'pad'
131                  must also have the 'len' property set.
132                enum: [ u8, u16, u32, u64, s8, s16, s32, s64, string, binary, pad ]
133              len:
134                $ref: '#/$defs/len-or-define'
135              byte-order:
136                enum: [ little-endian, big-endian ]
137              doc:
138                description: Documentation for the struct member attribute.
139                type: string
140              enum:
141                description: Name of the enum type used for the attribute.
142                type: string
143              enum-as-flags:
144                description: |
145                  Treat the enum as flags. In most cases enum is either used as flags or as values.
146                  Sometimes, however, both forms are necessary, in which case header contains the enum
147                  form while specific attributes may request to convert the values into a bitfield.
148                type: boolean
149              display-hint: &display-hint
150                description: |
151                  Optional format indicator that is intended only for choosing
152                  the right formatting mechanism when displaying values of this
153                  type.
154                enum: [ hex, mac, fddi, ipv4, ipv6, uuid ]
155            if:
156              properties:
157                type:
158                  oneOf:
159                    - const: binary
160                    - const: pad
161            then:
162              required: [ len ]
163        # End genetlink-legacy
164
165  attribute-sets:
166    description: Definition of attribute spaces for this family.
167    type: array
168    items:
169      description: Definition of a single attribute space.
170      type: object
171      required: [ name, attributes ]
172      additionalProperties: False
173      properties:
174        name:
175          description: |
176            Name used when referring to this space in other definitions, not used outside of the spec.
177          type: string
178        name-prefix:
179          description: |
180            Prefix for the C enum name of the attributes. Default family[name]-set[name]-a-
181          type: string
182        enum-name:
183          description: Name for the enum type of the attribute.
184          type: string
185        doc:
186          description: Documentation of the space.
187          type: string
188        subset-of:
189          description: |
190            Name of another space which this is a logical part of. Sub-spaces can be used to define
191            a limited group of attributes which are used in a nest.
192          type: string
193        # Start genetlink-c
194        attr-cnt-name:
195          description: The explicit name for constant holding the count of attributes (last attr + 1).
196          type: string
197        attr-max-name:
198          description: The explicit name for last member of attribute enum.
199          type: string
200        # End genetlink-c
201        attributes:
202          description: List of attributes in the space.
203          type: array
204          items:
205            type: object
206            required: [ name ]
207            additionalProperties: False
208            properties:
209              name:
210                type: string
211              type: &attr-type
212                description: The netlink attribute type
213                enum: [ unused, pad, flag, binary, bitfield32,
214                        u8, u16, u32, u64, s8, s16, s32, s64,
215                        string, nest, array-nest, nest-type-value,
216                        sub-message ]
217              doc:
218                description: Documentation of the attribute.
219                type: string
220              value:
221                description: Value for the enum item representing this attribute in the uAPI.
222                $ref: '#/$defs/uint'
223              type-value:
224                description: Name of the value extracted from the type of a nest-type-value attribute.
225                type: array
226                items:
227                  type: string
228              byte-order:
229                enum: [ little-endian, big-endian ]
230              multi-attr:
231                type: boolean
232              nested-attributes:
233                description: Name of the space (sub-space) used inside the attribute.
234                type: string
235              enum:
236                description: Name of the enum type used for the attribute.
237                type: string
238              enum-as-flags:
239                description: |
240                  Treat the enum as flags. In most cases enum is either used as flags or as values.
241                  Sometimes, however, both forms are necessary, in which case header contains the enum
242                  form while specific attributes may request to convert the values into a bitfield.
243                type: boolean
244              checks:
245                description: Kernel input validation.
246                type: object
247                additionalProperties: False
248                properties:
249                  flags-mask:
250                    description: Name of the flags constant on which to base mask (unsigned scalar types only).
251                    type: string
252                  min:
253                    description: Min value for an integer attribute.
254                    type: integer
255                  min-len:
256                    description: Min length for a binary attribute.
257                    $ref: '#/$defs/len-or-define'
258                  max-len:
259                    description: Max length for a string or a binary attribute.
260                    $ref: '#/$defs/len-or-define'
261                  exact-len:
262                    description: Exact length for a string or a binary attribute.
263                    $ref: '#/$defs/len-or-define'
264              sub-type: *attr-type
265              display-hint: *display-hint
266              # Start genetlink-c
267              name-prefix:
268                type: string
269              # End genetlink-c
270              # Start genetlink-legacy
271              struct:
272                description: Name of the struct type used for the attribute.
273                type: string
274              # End genetlink-legacy
275              # Start netlink-raw
276              sub-message:
277                description: |
278                  Name of the sub-message definition to use for the attribute.
279                type: string
280              selector:
281                description: |
282                  Name of the attribute to use for dynamic selection of sub-message
283                  format specifier.
284                type: string
285              # End netlink-raw
286
287      # Make sure name-prefix does not appear in subsets (subsets inherit naming)
288      dependencies:
289        name-prefix:
290          not:
291            required: [ subset-of ]
292        subset-of:
293          not:
294            required: [ name-prefix ]
295
296      # type property is only required if not in subset definition
297      if:
298        properties:
299          subset-of:
300            not:
301              type: string
302      then:
303        properties:
304          attributes:
305            items:
306              required: [ type ]
307
308  # Start netlink-raw
309  sub-messages:
310    description: Definition of sub message attributes
311    type: array
312    items:
313      type: object
314      additionalProperties: False
315      required: [ name, formats ]
316      properties:
317        name:
318          description: Name of the sub-message definition
319          type: string
320        formats:
321          description: Dynamically selected format specifiers
322          type: array
323          items:
324            type: object
325            additionalProperties: False
326            required: [ value ]
327            properties:
328              value:
329                description: |
330                  Value to match for dynamic selection of sub-message format
331                  specifier.
332                type: string
333              fixed-header:
334                description: |
335                  Name of the struct definition to use as the fixed header
336                  for the sub message.
337                type: string
338              attribute-set:
339                description: |
340                  Name of the attribute space from which to resolve attributes
341                  in the sub message.
342                type: string
343  # End netlink-raw
344
345  operations:
346    description: Operations supported by the protocol.
347    type: object
348    required: [ list ]
349    additionalProperties: False
350    properties:
351      enum-model:
352        description: |
353          The model of assigning values to the operations.
354          "unified" is the recommended model where all message types belong
355          to a single enum.
356          "directional" has the messages sent to the kernel and from the kernel
357          enumerated separately.
358        enum: [ unified, directional ] # Trim
359      name-prefix:
360        description: |
361          Prefix for the C enum name of the command. The name is formed by concatenating
362          the prefix with the upper case name of the command, with dashes replaced by underscores.
363        type: string
364      enum-name:
365        description: Name for the enum type with commands.
366        type: string
367      async-prefix:
368        description: Same as name-prefix but used to render notifications and events to separate enum.
369        type: string
370      async-enum:
371        description: Name for the enum type with notifications/events.
372        type: string
373      # Start genetlink-legacy
374      fixed-header: &fixed-header
375        description: |
376          Name of the structure defining the optional fixed-length protocol
377          header. This header is placed in a message after the netlink and
378          genetlink headers and before any attributes.
379        type: string
380      # End genetlink-legacy
381      list:
382        description: List of commands
383        type: array
384        items:
385          type: object
386          additionalProperties: False
387          required: [ name, doc ]
388          properties:
389            name:
390              description: Name of the operation, also defining its C enum value in uAPI.
391              type: string
392            doc:
393              description: Documentation for the command.
394              type: string
395            value:
396              description: Value for the enum in the uAPI.
397              $ref: '#/$defs/uint'
398            attribute-set:
399              description: |
400                Attribute space from which attributes directly in the requests and replies
401                to this command are defined.
402              type: string
403            flags: &cmd_flags
404              description: Command flags.
405              type: array
406              items:
407                enum: [ admin-perm ]
408            dont-validate:
409              description: Kernel attribute validation flags.
410              type: array
411              items:
412                enum: [ strict, dump ]
413            # Start genetlink-legacy
414            fixed-header: *fixed-header
415            # End genetlink-legacy
416            do: &subop-type
417              description: Main command handler.
418              type: object
419              additionalProperties: False
420              properties:
421                request: &subop-attr-list
422                  description: Definition of the request message for a given command.
423                  type: object
424                  additionalProperties: False
425                  properties:
426                    attributes:
427                      description: |
428                        Names of attributes from the attribute-set (not full attribute
429                        definitions, just names).
430                      type: array
431                      items:
432                        type: string
433                    # Start genetlink-legacy
434                    value:
435                      description: |
436                        ID of this message if value for request and response differ,
437                        i.e. requests and responses have different message enums.
438                      $ref: '#/$defs/uint'
439                    # End genetlink-legacy
440                reply: *subop-attr-list
441                pre:
442                  description: Hook for a function to run before the main callback (pre_doit or start).
443                  type: string
444                post:
445                  description: Hook for a function to run after the main callback (post_doit or done).
446                  type: string
447            dump: *subop-type
448            notify:
449              description: Name of the command sharing the reply type with this notification.
450              type: string
451            event:
452              type: object
453              additionalProperties: False
454              properties:
455                attributes:
456                  description: Explicit list of the attributes for the notification.
457                  type: array
458                  items:
459                    type: string
460            mcgrp:
461              description: Name of the multicast group generating given notification.
462              type: string
463  mcast-groups:
464    description: List of multicast groups.
465    type: object
466    required: [ list ]
467    additionalProperties: False
468    properties:
469      list:
470        description: List of groups.
471        type: array
472        items:
473          type: object
474          required: [ name ]
475          additionalProperties: False
476          properties:
477            name:
478              description: |
479                The name for the group, used to form the define and the value of the define.
480              type: string
481            # Start genetlink-c
482            c-define-name:
483              description: Override for the name of the define in C uAPI.
484              type: string
485            # End genetlink-c
486            flags: *cmd_flags
487            # Start netlink-raw
488            value:
489              description: Value of the netlink multicast group in the uAPI.
490              type: integer
491            # End netlink-raw
492