aboutsummaryrefslogtreecommitdiffstats
path: root/src/vpp-api/python/vpp_papi/vpp_serializer.py
blob: 707bb03b790defb67f19332ceb78927d6aaa718d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
#
# Copyright (c) 2018 Cisco and/or its affiliates.
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at:
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
import collections
from enum import IntFlag
import logging
import socket
import struct
import sys

from . import vpp_format


#
# Set log-level in application by doing e.g.:
# logger = logging.getLogger('vpp_serializer')
# logger.setLevel(logging.DEBUG)
#
logger = logging.getLogger("vpp_papi.serializer")


def check(d):
    return type(d) is dict or type(d) is bytes


def conversion_required(data, field_type):
    if check(data):
        return False
    try:
        if type(data).__name__ in vpp_format.conversion_table[field_type]:
            return True
    except KeyError:
        return False


def conversion_packer(data, field_type):
    t = type(data).__name__
    return types[field_type].pack(vpp_format.conversion_table[field_type][t](data))


def conversion_unpacker(data, field_type):
    if field_type not in vpp_format.conversion_unpacker_table:
        return data
    return vpp_format.conversion_unpacker_table[field_type](data)


class Packer:
    options = {}

    def pack(self, data, kwargs):
        raise NotImplementedError

    def unpack(self, data, offset, result=None, ntc=False):
        raise NotImplementedError

    # override as appropriate in subclasses
    @staticmethod
    def _get_packer_with_options(f_type, options):
        return types[f_type]

    def get_packer_with_options(self, f_type, options):
        if options is not None:
            try:
                c = types[f_type].__class__
                return c._get_packer_with_options(f_type, options)
            except IndexError:
                raise VPPSerializerValueError(
                    "Options not supported for {}{} ({})".format(
                        f_type, types[f_type].__class__, options
                    )
                )


class BaseTypes(Packer):
    def __init__(self, type, elements=0, options=None):
        self._type = type
        self._elements = elements
        base_types = {
            "u8": ">B",
            "i8": ">b",
            "string": ">s",
            "u16": ">H",
            "i16": ">h",
            "u32": ">I",
            "i32": ">i",
            "u64": ">Q",
            "i64": ">q",
            "f64": "=d",
            "bool": ">?",
            "header": ">HI",
        }

        if elements > 0 and (type == "u8" or type == "string"):
            self.packer = struct.Struct(">%ss" % elements)
        else:
            self.packer = struct.Struct(base_types[type])
        self.size = self.packer.size
        self.options = options

    def pack(self, data, kwargs=None):
        if data is None:  # Default to zero if not specified
            if self.options and "default" in self.options:
                data = self.options["default"]
            else:
                data = 0
        return self.packer.pack(data)

    def unpack(self, data, offset, result=None, ntc=False):
        return self.packer.unpack_from(data, offset)[0], self.packer.size

    @staticmethod
    def _get_packer_with_options(f_type, options):
        return BaseTypes(f_type, options=options)

    def __repr__(self):
        return "BaseTypes(type=%s, elements=%s, options=%s)" % (
            self._type,
            self._elements,
            self.options,
        )


class String(Packer):
    def __init__(self, name, num, options):
        self.name = name
        self.num = num
        self.size = num if num else 1
        self.length_field_packer = BaseTypes("u32")
        self.limit = options["limit"] if "limit" in options else num
        self.fixed = True if num else False
        if self.fixed and not self.limit:
            raise VPPSerializerValueError(
                "Invalid combination for: {}, {} fixed:{} limit:{}".format(
                    name, options, self.fixed, self.limit
                )
            )

    def pack(self, list, kwargs=None):
        if not list:
            if self.fixed:
                return b"\x00" * self.limit
            return self.length_field_packer.pack(0) + b""
        if self.limit and len(list) > self.limit - 1:
            raise VPPSerializerValueError(
                "Invalid argument length for: {}, {} maximum {}".format(
                    list, len(list), self.limit - 1
                )
            )
        if self.fixed:
            return list.encode("ascii").ljust(self.limit, b"\x00")
        return self.length_field_packer.pack(len(list)) + list.encode("ascii")

    def unpack(self, data, offset=0, result=None, ntc=False):
        if self.fixed:
            p = BaseTypes("u8", self.num)
            s = p.unpack(data, offset)
            s2 = s[0].split(b"\0", 1)[0]
            return (s2.decode("ascii"), self.num)

        length, length_field_size = self.length_field_packer.unpack(data, offset)
        if length == 0:
            return "", 0
        p = BaseTypes("u8", length)
        x, size = p.unpack(data, offset + length_field_size)
        return (x.decode("ascii", errors="replace"), size + length_field_size)


types = {
    "u8": BaseTypes("u8"),
    "i8": BaseTypes("i8"),
    "u16": BaseTypes("u16"),
    "i16": BaseTypes("i16"),
    "u32": BaseTypes("u32"),
    "i32": BaseTypes("i32"),
    "u64": BaseTypes("u64"),
    "i64": BaseTypes("i64"),
    "f64": BaseTypes("f64"),
    "bool": BaseTypes("bool"),
    "string": String,
}

class_types = {}


def vpp_get_type(name):
    try:
        return types[name]
    except KeyError:
        return None


class VPPSerializerValueError(ValueError):
    pass


class FixedList_u8(Packer):
    def __init__(self, name, field_type, num):
        self.name = name
        self.num = num
        self.packer = BaseTypes(field_type, num)
        self.size = self.packer.size
        self.field_type = field_type

    def pack(self, data, kwargs=None):
        """Packs a fixed length bytestring. Left-pads with zeros
        if input data is too short."""
        if not data:
            return b"\x00" * self.size

        if len(data) > self.num:
            raise VPPSerializerValueError(
                'Fixed list length error for "{}", got: {}'
                " expected: {}".format(self.name, len(data), self.num)
            )

        try:
            return self.packer.pack(data)
        except struct.error:
            raise VPPSerializerValueError(
                'Packing failed for "{}" {}'.format(self.name, kwargs)
            )

    def unpack(self, data, offset=0, result=None, ntc=False):
        if len(data[offset:]) < self.num:
            raise VPPSerializerValueError(
                'Invalid array length for "{}" got {}'
                " expected {}".format(self.name, len(data[offset:]), self.num)
            )
        return self.packer.unpack(data, offset)

    def __repr__(self):
        return "FixedList_u8(name=%s, field_type=%s, num=%s)" % (
            self.name,
            self.field_type,
            self.num,
        )


class FixedList(Packer):
    def __init__(self, name, field_type, num):
        self.num = num
        self.packer = types[field_type]
        self.size = self.packer.size * num
        self.name = name
        self.field_type = field_type

    def pack(self, list, kwargs):
        if len(list) != self.num:
            raise VPPSerializerValueError(
                "Fixed list length error, got: {} expected: {}".format(
                    len(list), self.num
                )
            )
        b = bytearray()
        for e in list:
            b += self.packer.pack(e)
        return bytes(b)

    def unpack(self, data, offset=0, result=None, ntc=False):
        # Return a list of arguments
        result = []
        total = 0
        for e in range(self.num):
            x, size = self.packer.unpack(data, offset, ntc=ntc)
            result.append(x)
            offset += size
            total += size
        return result, total

    def __repr__(self):
        return "FixedList(name=%s, field_type=%s, num=%s)" % (
            self.name,
            self.field_type,
            self.num,
        )


class VLAList(Packer):
    def __init__(self, name, field_type, len_field_name, index):
        self.name = name
        self.field_type = field_type
        self.index = index
        self.packer = types[field_type]
        self.size = self.packer.size
        self.length_field = len_field_name

    def pack(self, lst, kwargs=None):
        if not lst:
            return b""
        if len(lst) != kwargs[self.length_field]:
            raise VPPSerializerValueError(
                "Variable length error, got: {} expected: {}".format(
                    len(lst), kwargs[self.length_field]
                )
            )
        # u8 array
        if self.packer.size == 1 and self.field_type == "u8":
            if isinstance(lst, list):
                return b"".join(lst)
            return bytes(lst)

        b = bytearray()
        for e in lst:
            b += self.packer.pack(e)
        return bytes(b)

    def unpack(self, data, offset=0, result=None, ntc=False):
        # Return a list of arguments
        total = 0

        # u8 array
        if self.packer.size == 1 and self.field_type == "u8":
            if result[self.index] == 0:
                return b"", 0
            p = BaseTypes("u8", result[self.index])
            return p.unpack(data, offset, ntc=ntc)

        r = []
        for e in range(result[self.index]):
            x, size = self.packer.unpack(data, offset, ntc=ntc)
            r.append(x)
            offset += size
            total += size
        return r, total

    def __repr__(self):
        return "VLAList(name=%s, field_type=%s, " "len_field_name=%s, index=%s)" % (
            self.name,
            self.field_type,
            self.length_field,
            self.index,
        )


class VLAList_legacy(Packer):
    def __init__(self, name, field_type):
        self.name = name
        self.field_type = field_type
        self.packer = types[field_type]
        self.size = self.packer.size

    def pack(self, list, kwargs=None):
        if self.packer.size == 1:
            return bytes(list)

        b = bytearray()
        for e in list:
            b += self.packer.pack(e)
        return bytes(b)

    def unpack(self, data, offset=0, result=None, ntc=False):
        total = 0
        # Return a list of arguments
        if (len(data) - offset) % self.packer.size:
            raise VPPSerializerValueError(
                "Legacy Variable Length Array length mismatch."
            )
        elements = int((len(data) - offset) / self.packer.size)
        r = []
        for e in range(elements):
            x, size = self.packer.unpack(data, offset, ntc=ntc)
            r.append(x)
            offset += self.packer.size
            total += size
        return r, total

    def __repr__(self):
        return "VLAList_legacy(name=%s, field_type=%s)" % (self.name, self.field_type)


# Will change to IntEnum after 21.04 release
class VPPEnumType(Packer):
    output_class = IntFlag

    def __init__(self, name, msgdef, options=None):
        self.size = types["u32"].size
        self.name = name
        self.enumtype = "u32"
        self.msgdef = msgdef
        e_hash = {}
        for f in msgdef:
            if type(f) is dict and "enumtype" in f:
                if f["enumtype"] != "u32":
                    self.size = types[f["enumtype"]].size
                    self.enumtype = f["enumtype"]
                continue
            ename, evalue = f
            e_hash[ename] = evalue
        self.enum = self.output_class(name, e_hash)
        types[name] = self
        class_types[name] = self.__class__
        self.options = options

    def __getattr__(self, name):
        return self.enum[name]

    def __bool__(self):
        return True

    def pack(self, data, kwargs=None):
        if data is None:  # Default to zero if not specified
            if self.options and "default" in self.options:
                data = self.options["default"]
            else:
                data = 0

        return types[self.enumtype].pack(data)

    def unpack(self, data, offset=0, result=None, ntc=False):
        x, size = types[self.enumtype].unpack(data, offset)
        return self.enum(x), size

    @classmethod
    def _get_packer_with_options(cls, f_type, options):
        return cls(f_type, types[f_type].msgdef, options=options)

    def __repr__(self):
        return "%s(name=%s, msgdef=%s, options=%s)" % (
            self.__class__.__name__,
            self.name,
            self.msgdef,
            self.options,
        )


class VPPEnumFlagType(VPPEnumType):
    output_class = IntFlag

    def __init__(self, name, msgdef, options=None):
        super(VPPEnumFlagType, self).__init__(name, msgdef, options)


class VPPUnionType(Packer):
    def __init__(self, name, msgdef):
        self.name = name
        self.msgdef = msgdef
        self.size = 0
        self.maxindex = 0
        fields = []
        self.packers = collections.OrderedDict()
        for i, f in enumerate(msgdef):
            if type(f) is dict and "crc" in f:
                self.crc = f["crc"]
                continue
            f_type, f_name = f
            if f_type not in types:
                logger.debug("Unknown union type {}".format(f_type))
                raise VPPSerializerValueError("Unknown message type {}".format(f_type))
            fields.append(f_name)
            size = types[f_type].size
            self.packers[f_name] = types[f_type]
            if size > self.size:
                self.size = size
                self.maxindex = i

        types[name] = self
        self.tuple = collections.namedtuple(name, fields, rename=True)

    # Union of variable length?
    def pack(self, data, kwargs=None):
        if not data:
            return b"\x00" * self.size

        for k, v in data.items():
            logger.debug("Key: {} Value: {}".format(k, v))
            b = self.packers[k].pack(v, kwargs)
            break
        r = bytearray(self.size)
        r[: len(b)] = b
        return r

    def unpack(self, data, offset=0, result=None, ntc=False):
        r = []
        maxsize = 0
        for k, p in self.packers.items():
            x, size = p.unpack(data, offset, ntc=ntc)
            if size > maxsize:
                maxsize = size
            r.append(x)
        return self.tuple._make(r), maxsize

    def __repr__(self):
        return "VPPUnionType(name=%s, msgdef=%r)" % (self.name, self.msgdef)


class VPPTypeAlias(Packer):
    def __init__(self, name, msgdef, options=None):
        self.name = name
        self.msgdef = msgdef
        t = vpp_get_type(msgdef["type"])
        if not t:
            raise ValueError("No such type: {}".format(msgdef["type"]))
        if "length" in msgdef:
            if msgdef["length"] == 0:
                raise ValueError()
            if msgdef["type"] == "u8":
                self.packer = FixedList_u8(name, msgdef["type"], msgdef["length"])
                self.size = self.packer.size
            else:
                self.packer = FixedList(name, msgdef["type"], msgdef["length"])
        else:
            self.packer = t
            self.size = t.size

        types[name] = self
        self.toplevelconversion = False
        self.options = options

    def pack(self, data, kwargs=None):
        if data and conversion_required(data, self.name):
            try:
                return conversion_packer(data, self.name)
            # Python 2 and 3 raises different exceptions from inet_pton
            except (OSError, socket.error, TypeError):
                pass
        if data is None:  # Default to zero if not specified
            if self.options and "default" in self.options:
                data = self.options["default"]
            else:
                data = 0

        return self.packer.pack(data, kwargs)

    @staticmethod
    def _get_packer_with_options(f_type, options):
        return VPPTypeAlias(f_type, types[f_type].msgdef, options=options)

    def unpack(self, data, offset=0, result=None, ntc=False):
        if ntc is False and self.name in vpp_format.conversion_unpacker_table:
            # Disable type conversion for dependent types
            ntc = True
            self.toplevelconversion = True
        t, size = self.packer.unpack(data, offset, result, ntc=ntc)
        if self.toplevelconversion:
            self.toplevelconversion = False
            return conversion_unpacker(t, self.name), size
        return t, size

    def __repr__(self):
        return "VPPTypeAlias(name=%s, msgdef=%s, options=%s)" % (
            self.name,
            self.msgdef,
            self.options,
        )


class VPPType(Packer):
    # Set everything up to be able to pack / unpack
    def __init__(self, name, msgdef):
        self.name = name
        self.msgdef = msgdef
        self.packers = []
        self.fields = []
        self.fieldtypes = []
        self.field_by_name = {}
        size = 0
        for i, f in enumerate(msgdef):
            if type(f) is dict and "crc" in f:
                self.crc = f["crc"]
                continue
            f_type, f_name = f[:2]
            self.fields.append(f_name)
            self.field_by_name[f_name] = None
            self.fieldtypes.append(f_type)
            if f_type not in types:
                logger.debug("Unknown type {}".format(f_type))
                raise VPPSerializerValueError("Unknown message type {}".format(f_type))

            fieldlen = len(f)
            options = [x for x in f if type(x) is dict]
            if len(options):
                self.options = options[0]
                fieldlen -= 1
            else:
                self.options = {}
            if fieldlen == 3:  # list
                list_elements = f[2]
                if list_elements == 0:
                    if f_type == "string":
                        p = String(f_name, 0, self.options)
                    else:
                        p = VLAList_legacy(f_name, f_type)
                    self.packers.append(p)
                elif f_type == "u8":
                    p = FixedList_u8(f_name, f_type, list_elements)
                    self.packers.append(p)
                    size += p.size
                elif f_type == "string":
                    p = String(f_name, list_elements, self.options)
                    self.packers.append(p)
                    size += p.size
                else:
                    p = FixedList(f_name, f_type, list_elements)
                    self.packers.append(p)
                    size += p.size
            elif fieldlen == 4:  # Variable length list
                length_index = self.fields.index(f[3])
                p = VLAList(f_name, f_type, f[3], length_index)
                self.packers.append(p)
            else:
                # default support for types that decay to basetype
                if "default" in self.options:
                    p = self.get_packer_with_options(f_type, self.options)
                else:
                    p = types[f_type]

                self.packers.append(p)
                size += p.size
        self.size = size
        self.tuple = collections.namedtuple(name, self.fields, rename=True)
        types[name] = self
        self.toplevelconversion = False

    def pack(self, data, kwargs=None):
        if not kwargs:
            kwargs = data
        b = bytearray()

        # Try one of the format functions
        if data and conversion_required(data, self.name):
            return conversion_packer(data, self.name)

        for i, a in enumerate(self.fields):
            if data and type(data) is not dict and a not in data:
                raise VPPSerializerValueError(
                    "Invalid argument: {} expected {}.{}".format(data, self.name, a)
                )

            # Defaulting to zero.
            if not data or a not in data:  # Default to 0
                arg = None
                kwarg = None  # No default for VLA
            else:
                arg = data[a]
                kwarg = kwargs[a] if a in kwargs else None
            try:
                if isinstance(self.packers[i], VPPType):
                    b += self.packers[i].pack(arg, kwarg)
                else:
                    b += self.packers[i].pack(arg, kwargs)
            except Exception as e:
                raise VPPSerializerValueError(
                    f"Exception while packing {data} for {self.name}.{a}."
                ) from e

        return bytes(b)

    def unpack(self, data, offset=0, result=None, ntc=False):
        # Return a list of arguments
        result = []
        total = 0
        if ntc is False and self.name in vpp_format.conversion_unpacker_table:
            # Disable type conversion for dependent types
            ntc = True
            self.toplevelconversion = True

        for p in self.packers:
            x, size = p.unpack(data, offset, result, ntc)
            if type(x) is tuple and len(x) == 1:
                x = x[0]
            result.append(x)
            offset += size
            total += size
        t = self.tuple._make(result)

        if self.toplevelconversion:
            self.toplevelconversion = False
            t = conversion_unpacker(t, self.name)
        return t, total

    def __repr__(self):
        return "%s(name=%s, msgdef=%s)" % (
            self.__class__.__name__,
            self.name,
            self.msgdef,
        )


class VPPMessage(VPPType):
    pass