def encode(*args, to_base64=False):
"""Encode the given byte args in TLV format.
:param args: Even-number, variable length positional arguments repeating a tag
followed by a value.
:type args: ``bytes``
:param toBase64: Whether to encode the resuting TLV byte sequence to a base64 str.
:type toBase64: ``bool``
:return: The args in TLV format
:rtype: ``bytes`` if ``toBase64`` is False and ``str`` otherwise.
"""
if len(args) % 2 != 0:
raise ValueError("Even number of args expected (%d given)" % len(args))
pieces = []
for x in range(0, len(args), 2):
tag = args[x]
data = args[x + 1]
total_length = len(data)
if len(data) <= 255:
encoded = tag + struct.pack("B", total_length) + data
else:
encoded = b""
for y in range(0, total_length // 255):
encoded = encoded + tag + b"\xFF" + data[y * 255 : (y + 1) * 255]
remaining = total_length % 255
encoded = encoded + tag + struct.pack("B", remaining) + data[-remaining:]
pieces.append(encoded)
result = b"".join(pieces)
return util.to_base64_str(result) if to_base64 else result
def set_endpoints(self, value):
"""Configure streaming endpoints.
Called when iOS sets the SetupEndpoints ``Characteristic``. The endpoint
information for the camera should be set as the current value of SetupEndpoints.
:param value: The base64-encoded stream session details in TLV format.
:param value: ``str``
"""
objs = tlv.decode(value, from_base64=True)
session_id = UUID(bytes=objs[SETUP_TYPES['SESSION_ID']])
# Extract address info
address_tlv = objs[SETUP_TYPES['ADDRESS']]
address_info_objs = tlv.decode(address_tlv)
is_ipv6 = struct.unpack(
'?', address_info_objs[SETUP_ADDR_INFO['ADDRESS_VER']])[0]
address = address_info_objs[SETUP_ADDR_INFO['ADDRESS']].decode('utf8')
target_video_port = struct.unpack(
'<H', address_info_objs[SETUP_ADDR_INFO['VIDEO_RTP_PORT']])[0]
target_audio_port = struct.unpack(
'<H', address_info_objs[SETUP_ADDR_INFO['AUDIO_RTP_PORT']])[0]
# Video SRTP Params
video_srtp_tlv = objs[SETUP_TYPES['VIDEO_SRTP_PARAM']]
video_info_objs = tlv.decode(video_srtp_tlv)
video_crypto_suite = video_info_objs[SETUP_SRTP_PARAM['CRYPTO']][0]
video_master_key = video_info_objs[SETUP_SRTP_PARAM['MASTER_KEY']]
video_master_salt = video_info_objs[SETUP_SRTP_PARAM['MASTER_SALT']]
# Audio SRTP Params
audio_srtp_tlv = objs[SETUP_TYPES['AUDIO_SRTP_PARAM']]
audio_info_objs = tlv.decode(audio_srtp_tlv)
audio_crypto_suite = audio_info_objs[SETUP_SRTP_PARAM['CRYPTO']][0]
audio_master_key = audio_info_objs[SETUP_SRTP_PARAM['MASTER_KEY']]
audio_master_salt = audio_info_objs[SETUP_SRTP_PARAM['MASTER_SALT']]
logger.debug(
'Received endpoint configuration:'
'\nsession_id: %s\naddress: %s\nis_ipv6: %s'
'\ntarget_video_port: %s\ntarget_audio_port: %s'
'\nvideo_crypto_suite: %s\nvideo_srtp: %s'
'\naudio_crypto_suite: %s\naudio_srtp: %s', session_id, address,
is_ipv6, target_video_port, target_audio_port, video_crypto_suite,
to_base64_str(video_master_key + video_master_salt),
audio_crypto_suite,
to_base64_str(audio_master_key + audio_master_salt))
# Configure the SetupEndpoints response
if self.has_srtp:
video_srtp_tlv = tlv.encode(
SETUP_SRTP_PARAM['CRYPTO'],
SRTP_CRYPTO_SUITES['AES_CM_128_HMAC_SHA1_80'],
SETUP_SRTP_PARAM['MASTER_KEY'], video_master_key,
SETUP_SRTP_PARAM['MASTER_SALT'], video_master_salt)
audio_srtp_tlv = tlv.encode(
SETUP_SRTP_PARAM['CRYPTO'],
SRTP_CRYPTO_SUITES['AES_CM_128_HMAC_SHA1_80'],
SETUP_SRTP_PARAM['MASTER_KEY'], audio_master_key,
SETUP_SRTP_PARAM['MASTER_SALT'], audio_master_salt)
else:
video_srtp_tlv = NO_SRTP
audio_srtp_tlv = NO_SRTP
video_ssrc = int.from_bytes(os.urandom(3), byteorder="big")
audio_ssrc = int.from_bytes(os.urandom(3), byteorder="big")
res_address_tlv = tlv.encode(SETUP_ADDR_INFO['ADDRESS_VER'],
self.stream_address_isv6,
SETUP_ADDR_INFO['ADDRESS'],
self.stream_address.encode('utf-8'),
SETUP_ADDR_INFO['VIDEO_RTP_PORT'],
struct.pack('<H', target_video_port),
SETUP_ADDR_INFO['AUDIO_RTP_PORT'],
struct.pack('<H', target_audio_port))
response_tlv = tlv.encode(SETUP_TYPES['SESSION_ID'],
session_id.bytes,
SETUP_TYPES['STATUS'],
SETUP_STATUS['SUCCESS'],
SETUP_TYPES['ADDRESS'],
res_address_tlv,
SETUP_TYPES['VIDEO_SRTP_PARAM'],
video_srtp_tlv,
SETUP_TYPES['AUDIO_SRTP_PARAM'],
audio_srtp_tlv,
SETUP_TYPES['VIDEO_SSRC'],
struct.pack('<I', video_ssrc),
SETUP_TYPES['AUDIO_SSRC'],
struct.pack('<I', audio_ssrc),
to_base64=True)
self.sessions[session_id] = {
'id': session_id,
'address': address,
'v_port': target_video_port,
'v_srtp_key': to_base64_str(video_master_key + video_master_salt),
'v_ssrc': video_ssrc,
'a_port': target_audio_port,
'a_srtp_key': to_base64_str(audio_master_key + audio_master_salt),
'a_ssrc': audio_ssrc
}
self.get_service('CameraRTPStreamManagement')\
.get_characteristic('SetupEndpoints')\
.set_value(response_tlv)
def get_supported_audio_stream_config(audio_params):
"""Return a tlv representation of the supported audio stream configuration.
iOS supports only AACELD and OPUS
Expected audio parameters:
- codecs
- comfort_noise
:param audio_params: Supported audio configurations
:type audio_params: dict
"""
has_supported_codec = False
configs = b''
for codec_param in audio_params['codecs']:
param_type = codec_param['type']
if param_type == 'OPUS':
has_supported_codec = True
codec = AUDIO_CODEC_TYPES['OPUS']
bitrate = AUDIO_CODEC_PARAM_BIT_RATE_TYPES['VARIABLE']
elif param_type == 'AAC-eld':
has_supported_codec = True
codec = AUDIO_CODEC_TYPES['AACELD']
bitrate = AUDIO_CODEC_PARAM_BIT_RATE_TYPES['VARIABLE']
else:
logger.warning('Unsupported codec %s', param_type)
continue
param_samplerate = codec_param['samplerate']
if param_samplerate == 8:
samplerate = AUDIO_CODEC_PARAM_SAMPLE_RATE_TYPES['KHZ_8']
elif param_samplerate == 16:
samplerate = AUDIO_CODEC_PARAM_SAMPLE_RATE_TYPES['KHZ_16']
elif param_samplerate == 24:
samplerate = AUDIO_CODEC_PARAM_SAMPLE_RATE_TYPES['KHZ_24']
else:
logger.warning('Unsupported sample rate %s', param_samplerate)
continue
param_tlv = tlv.encode(AUDIO_CODEC_PARAM_TYPES['CHANNEL'], b'\x01',
AUDIO_CODEC_PARAM_TYPES['BIT_RATE'],
bitrate,
AUDIO_CODEC_PARAM_TYPES['SAMPLE_RATE'],
samplerate)
config_tlv = tlv.encode(AUDIO_TYPES['CODEC'], codec,
AUDIO_TYPES['CODEC_PARAM'], param_tlv)
configs += tlv.encode(SUPPORTED_AUDIO_CODECS_TAG, config_tlv)
if not has_supported_codec:
logger.warning(
'Client does not support any audio codec that iOS supports.')
codec = AUDIO_CODEC_TYPES['OPUS']
bitrate = AUDIO_CODEC_PARAM_BIT_RATE_TYPES['VARIABLE']
samplerate = AUDIO_CODEC_PARAM_SAMPLE_RATE_TYPES['KHZ_24']
param_tlv = tlv.encode(AUDIO_CODEC_PARAM_TYPES['CHANNEL'], b'\x01',
AUDIO_CODEC_PARAM_TYPES['BIT_RATE'],
bitrate,
AUDIO_CODEC_PARAM_TYPES['SAMPLE_RATE'],
samplerate)
config_tlv = tlv.encode(AUDIO_TYPES['CODEC'], codec,
AUDIO_TYPES['CODEC_PARAM'], param_tlv)
configs = tlv.encode(SUPPORTED_AUDIO_CODECS_TAG, config_tlv)
comfort_noise = byte_bool(audio_params.get('comfort_noise', False))
audio_config = to_base64_str(
configs + tlv.encode(SUPPORTED_COMFORT_NOISE_TAG, comfort_noise))
return audio_config