2 # Copyright (c) 2018 Cisco and/or its affiliates.
3 # Licensed under the Apache License, Version 2.0 (the "License");
4 # you may not use this file except in compliance with the License.
5 # You may obtain a copy of the License at:
7 # http://www.apache.org/licenses/LICENSE-2.0
9 # Unless required by applicable law or agreed to in writing, software
10 # distributed under the License is distributed on an "AS IS" BASIS,
11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 # See the License for the specific language governing permissions and
13 # limitations under the License.
18 from enum import IntEnum
20 from . import vpp_format
26 # Set log-level in application by doing e.g.:
27 # logger = logging.getLogger('vpp_serializer')
28 # logger.setLevel(logging.DEBUG)
30 logger = logging.getLogger(__name__)
32 if sys.version[0] == '2':
33 check = lambda d: type(d) is dict
35 check = lambda d: type(d) is dict or type(d) is bytes
37 def conversion_required(data, field_type):
41 if type(data).__name__ in vpp_format.conversion_table[field_type]:
47 def conversion_packer(data, field_type):
48 t = type(data).__name__
49 return types[field_type].pack(vpp_format.
50 conversion_table[field_type][t](data))
53 def conversion_unpacker(data, field_type):
54 if field_type not in vpp_format.conversion_unpacker_table:
56 return vpp_format.conversion_unpacker_table[field_type](data)
59 class BaseTypes(object):
60 def __init__(self, type, elements=0):
61 base_types = {'u8': '>B',
71 if elements > 0 and (type == 'u8' or type == 'string'):
72 self.packer = struct.Struct('>%ss' % elements)
74 self.packer = struct.Struct(base_types[type])
75 self.size = self.packer.size
77 def pack(self, data, kwargs=None):
78 if not data: # Default to zero if not specified
80 return self.packer.pack(data)
82 def unpack(self, data, offset, result=None, ntc=False):
83 return self.packer.unpack_from(data, offset)[0], self.packer.size
90 self.length_field_packer = BaseTypes('u32')
92 def pack(self, list, kwargs=None):
94 return self.length_field_packer.pack(0) + b""
95 return self.length_field_packer.pack(len(list)) + list.encode('utf8')
97 def unpack(self, data, offset=0, result=None, ntc=False):
98 length, length_field_size = self.length_field_packer.unpack(data,
102 p = BaseTypes('u8', length)
103 x, size = p.unpack(data, offset + length_field_size)
104 x2 = x.split(b'\0',1)[0]
105 return (x2.decode('utf8'), size + length_field_size)
108 types = {'u8': BaseTypes('u8'), 'u16': BaseTypes('u16'),
109 'u32': BaseTypes('u32'), 'i32': BaseTypes('i32'),
110 'u64': BaseTypes('u64'), 'f64': BaseTypes('f64'),
111 'bool': BaseTypes('bool'), 'string': String()}
114 def vpp_get_type(name):
121 class VPPSerializerValueError(ValueError):
125 class FixedList_u8(object):
126 def __init__(self, name, field_type, num):
129 self.packer = BaseTypes(field_type, num)
130 self.size = self.packer.size
131 self.field_type = field_type
133 def pack(self, data, kwargs=None):
134 """Packs a fixed length bytestring. Left-pads with zeros
135 if input data is too short."""
137 return b'\x00' * self.size
139 if len(data) > self.num:
140 raise VPPSerializerValueError(
141 'Fixed list length error for "{}", got: {}'
143 .format(self.name, len(data), self.num))
145 return self.packer.pack(data)
147 def unpack(self, data, offset=0, result=None, ntc=False):
148 if len(data[offset:]) < self.num:
149 raise VPPSerializerValueError(
150 'Invalid array length for "{}" got {}'
152 .format(self.name, len(data[offset:]), self.num))
153 if self.field_type == 'string':
154 s = self.packer.unpack(data, offset)
155 s2 = s[0].split(b'\0', 1)[0]
156 return (s2.decode('utf-8'), self.num)
157 return self.packer.unpack(data, offset)
160 class FixedList(object):
161 def __init__(self, name, field_type, num):
163 self.packer = types[field_type]
164 self.size = self.packer.size * num
166 self.field_type = field_type
168 def pack(self, list, kwargs):
169 if len(list) != self.num:
170 raise VPPSerializerValueError(
171 'Fixed list length error, got: {} expected: {}'
172 .format(len(list), self.num))
175 b += self.packer.pack(e)
178 def unpack(self, data, offset=0, result=None, ntc=False):
179 # Return a list of arguments
182 for e in range(self.num):
183 x, size = self.packer.unpack(data, offset, ntc=ntc)
190 class VLAList(object):
191 def __init__(self, name, field_type, len_field_name, index):
193 self.field_type = field_type
195 self.packer = types[field_type]
196 self.size = self.packer.size
197 self.length_field = len_field_name
199 def pack(self, list, kwargs=None):
202 if len(list) != kwargs[self.length_field]:
203 raise VPPSerializerValueError(
204 'Variable length error, got: {} expected: {}'
205 .format(len(list), kwargs[self.length_field]))
210 if self.packer.size == 1:
211 return bytearray(list)
214 b += self.packer.pack(e)
217 def unpack(self, data, offset=0, result=None, ntc=False):
218 # Return a list of arguments
222 if self.packer.size == 1:
223 if result[self.index] == 0:
225 p = BaseTypes('u8', result[self.index])
226 return p.unpack(data, offset, ntc=ntc)
229 for e in range(result[self.index]):
230 x, size = self.packer.unpack(data, offset, ntc=ntc)
237 class VLAList_legacy():
238 def __init__(self, name, field_type):
239 self.packer = types[field_type]
240 self.size = self.packer.size
242 def pack(self, list, kwargs=None):
243 if self.packer.size == 1:
248 b += self.packer.pack(e)
251 def unpack(self, data, offset=0, result=None, ntc=False):
253 # Return a list of arguments
254 if (len(data) - offset) % self.packer.size:
255 raise VPPSerializerValueError(
256 'Legacy Variable Length Array length mismatch.')
257 elements = int((len(data) - offset) / self.packer.size)
259 for e in range(elements):
260 x, size = self.packer.unpack(data, offset, ntc=ntc)
262 offset += self.packer.size
267 class VPPEnumType(object):
268 def __init__(self, name, msgdef):
269 self.size = types['u32'].size
272 if type(f) is dict and 'enumtype' in f:
273 if f['enumtype'] != 'u32':
274 raise NotImplementedError
277 e_hash[ename] = evalue
278 self.enum = IntEnum(name, e_hash)
281 def __getattr__(self, name):
282 return self.enum[name]
284 def __nonzero__(self):
287 def pack(self, data, kwargs=None):
288 return types['u32'].pack(data)
290 def unpack(self, data, offset=0, result=None, ntc=False):
291 x, size = types['u32'].unpack(data, offset)
292 return self.enum(x), size
295 class VPPUnionType(object):
296 def __init__(self, name, msgdef):
301 self.packers = collections.OrderedDict()
302 for i, f in enumerate(msgdef):
303 if type(f) is dict and 'crc' in f:
307 if f_type not in types:
308 logger.debug('Unknown union type {}'.format(f_type))
309 raise VPPSerializerValueError(
310 'Unknown message type {}'.format(f_type))
311 fields.append(f_name)
312 size = types[f_type].size
313 self.packers[f_name] = types[f_type]
319 self.tuple = collections.namedtuple(name, fields, rename=True)
321 # Union of variable length?
322 def pack(self, data, kwargs=None):
324 return b'\x00' * self.size
326 for k, v in data.items():
327 logger.debug("Key: {} Value: {}".format(k, v))
328 b = self.packers[k].pack(v, kwargs)
330 r = bytearray(self.size)
334 def unpack(self, data, offset=0, result=None, ntc=False):
337 for k, p in self.packers.items():
338 x, size = p.unpack(data, offset, ntc=ntc)
342 return self.tuple._make(r), maxsize
345 class VPPTypeAlias(object):
346 def __init__(self, name, msgdef):
348 t = vpp_get_type(msgdef['type'])
351 if 'length' in msgdef:
352 if msgdef['length'] == 0:
354 if msgdef['type'] == 'u8':
355 self.packer = FixedList_u8(name, msgdef['type'],
357 self.size = self.packer.size
359 self.packer = FixedList(name, msgdef['type'], msgdef['length'])
366 def pack(self, data, kwargs=None):
367 if data and conversion_required(data, self.name):
369 return conversion_packer(data, self.name)
370 # Python 2 and 3 raises different exceptions from inet_pton
371 except(OSError, socket.error, TypeError):
374 return self.packer.pack(data, kwargs)
376 def unpack(self, data, offset=0, result=None, ntc=False):
377 t, size = self.packer.unpack(data, offset, result, ntc=ntc)
379 return conversion_unpacker(t, self.name), size
383 class VPPType(object):
384 # Set everything up to be able to pack / unpack
385 def __init__(self, name, msgdef):
391 self.field_by_name = {}
393 for i, f in enumerate(msgdef):
394 if type(f) is dict and 'crc' in f:
397 f_type, f_name = f[:2]
398 self.fields.append(f_name)
399 self.field_by_name[f_name] = None
400 self.fieldtypes.append(f_type)
401 if f_type not in types:
402 logger.debug('Unknown type {}'.format(f_type))
403 raise VPPSerializerValueError(
404 'Unknown message type {}'.format(f_type))
405 if len(f) == 3: # list
407 if list_elements == 0:
408 p = VLAList_legacy(f_name, f_type)
409 self.packers.append(p)
410 elif f_type == 'u8' or f_type == 'string':
411 p = FixedList_u8(f_name, f_type, list_elements)
412 self.packers.append(p)
415 p = FixedList(f_name, f_type, list_elements)
416 self.packers.append(p)
418 elif len(f) == 4: # Variable length list
419 length_index = self.fields.index(f[3])
420 p = VLAList(f_name, f_type, f[3], length_index)
421 self.packers.append(p)
423 self.packers.append(types[f_type])
424 size += types[f_type].size
427 self.tuple = collections.namedtuple(name, self.fields, rename=True)
430 def pack(self, data, kwargs=None):
435 # Try one of the format functions
436 if data and conversion_required(data, self.name):
437 return conversion_packer(data, self.name)
439 for i, a in enumerate(self.fields):
440 if data and type(data) is not dict and a not in data:
441 raise VPPSerializerValueError(
442 "Invalid argument: {} expected {}.{}".
443 format(data, self.name, a))
445 # Defaulting to zero.
446 if not data or a not in data: # Default to 0
448 kwarg = None # No default for VLA
451 kwarg = kwargs[a] if a in kwargs else None
452 if isinstance(self.packers[i], VPPType):
453 b += self.packers[i].pack(arg, kwarg)
455 b += self.packers[i].pack(arg, kwargs)
459 def unpack(self, data, offset=0, result=None, ntc=False):
460 # Return a list of arguments
463 for p in self.packers:
464 x, size = p.unpack(data, offset, result, ntc)
465 if type(x) is tuple and len(x) == 1:
470 t = self.tuple._make(result)
472 t = conversion_unpacker(t, self.name)
476 class VPPMessage(VPPType):