def close_multicast_socket(sock, address):
"""
Cleans up the given multicast socket.
Unregisters it of the multicast group.
Parameters should be the result of create_multicast_socket
:param sock: A multicast socket
:param address: The multicast address used by the socket
"""
if sock is None:
return
if address:
# Prepare the mreq structure to join the group
mreq = make_mreq(sock.family, address)
# Quit group
if sock.family == socket.AF_INET:
# IPv4
sock.setsockopt(socket.IPPROTO_IP, socket.IP_DROP_MEMBERSHIP, mreq)
elif sock.family == socket.AF_INET6:
# IPv6
sock.setsockopt(ipproto_ipv6(), socket.IPV6_LEAVE_GROUP, mreq)
# Close the socket
sock.close()
def close_multicast_socket(sock, address):
"""
Cleans up the given multicast socket.
Unregisters it of the multicast group.
Parameters should be the result of create_multicast_socket
:param sock: A multicast socket
:param address: The multicast address used by the socket
"""
if sock is None:
return
if address:
# Prepare the mreq structure to join the group
mreq = make_mreq(sock.family, address)
# Quit group
if sock.family == socket.AF_INET:
# IPv4
sock.setsockopt(socket.IPPROTO_IP, socket.IP_DROP_MEMBERSHIP, mreq)
elif sock.family == socket.AF_INET6:
# IPv6
sock.setsockopt(ipproto_ipv6(), socket.IPV6_LEAVE_GROUP, mreq)
# Close the socket
sock.close()
def create_multicast_socket(address, port):
"""
Creates a multicast socket according to the given address and port.
Handles both IPv4 and IPv6 addresses.
:param address: Multicast address/group
:param port: Socket port
:return: A tuple (socket, listening address)
:raise ValueError: Invalid address or port
"""
# Get the information about a datagram (UDP) socket, of any family
try:
addrs_info = socket.getaddrinfo(
address, port, socket.AF_UNSPEC, socket.SOCK_DGRAM
)
except socket.gaierror:
raise ValueError(
"Error retrieving address informations ({0}, {1})".format(
address, port
)
)
if len(addrs_info) > 1:
_logger.debug(
"More than one address information found. Using the first one."
)
# Get the first entry : (family, socktype, proto, canonname, sockaddr)
addr_info = addrs_info[0]
# Only accept IPv4/v6 addresses
if addr_info[0] not in (socket.AF_INET, socket.AF_INET6):
# Unhandled address family
raise ValueError("Unhandled socket family : %d" % (addr_info[0]))
# Prepare the socket
sock = socket.socket(addr_info[0], socket.SOCK_DGRAM, socket.IPPROTO_UDP)
# Reuse address
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
if hasattr(socket, "SO_REUSEPORT"):
# Special for MacOS
# pylint: disable=E1101
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEPORT, 1)
# Bind the socket
if sock.family == socket.AF_INET:
# IPv4 binding
sock.bind(("0.0.0.0", port))
else:
# IPv6 Binding
sock.bind(("::", port))
# Prepare the mreq structure to join the group
# addrinfo[4] = (addr,port)
mreq = make_mreq(sock.family, addr_info[4][0])
# Join the group
if sock.family == socket.AF_INET:
# IPv4
sock.setsockopt(socket.IPPROTO_IP, socket.IP_ADD_MEMBERSHIP, mreq)
# Allow multicast packets to get back on this host
sock.setsockopt(socket.IPPROTO_IP, socket.IP_MULTICAST_LOOP, 1)
elif sock.family == socket.AF_INET6:
# IPv6
sock.setsockopt(ipproto_ipv6(), socket.IPV6_JOIN_GROUP, mreq)
# Allow multicast packets to get back on this host
sock.setsockopt(ipproto_ipv6(), socket.IPV6_MULTICAST_LOOP, 1)
return sock, addr_info[4][0]
def create_multicast_socket(address, port):
"""
Creates a multicast socket according to the given address and port.
Handles both IPv4 and IPv6 addresses.
:param address: Multicast address/group
:param port: Socket port
:return: A tuple (socket, listening address)
:raise ValueError: Invalid address or port
"""
# Get the information about a datagram (UDP) socket, of any family
try:
addrs_info = socket.getaddrinfo(address, port, socket.AF_UNSPEC,
socket.SOCK_DGRAM)
except socket.gaierror:
raise ValueError(
"Error retrieving address informations ({0}, {1})".format(
address, port))
if len(addrs_info) > 1:
_logger.debug("More than one address information found. "
"Using the first one.")
# Get the first entry : (family, socktype, proto, canonname, sockaddr)
addr_info = addrs_info[0]
# Only accept IPv4/v6 addresses
if addr_info[0] not in (socket.AF_INET, socket.AF_INET6):
# Unhandled address family
raise ValueError("Unhandled socket family : %d" % (addr_info[0]))
# Prepare the socket
sock = socket.socket(addr_info[0], socket.SOCK_DGRAM, socket.IPPROTO_UDP)
# Reuse address
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
if hasattr(socket, 'SO_REUSEPORT'):
# Special for MacOS
# pylint: disable=E1101
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEPORT, 1)
# Bind the socket
if sock.family == socket.AF_INET:
# IPv4 binding
sock.bind(('0.0.0.0', port))
else:
# IPv6 Binding
sock.bind(('::', port))
# Prepare the mreq structure to join the group
# addrinfo[4] = (addr,port)
mreq = make_mreq(sock.family, addr_info[4][0])
# Join the group
if sock.family == socket.AF_INET:
# IPv4
sock.setsockopt(socket.IPPROTO_IP, socket.IP_ADD_MEMBERSHIP, mreq)
# Allow multicast packets to get back on this host
sock.setsockopt(socket.IPPROTO_IP, socket.IP_MULTICAST_LOOP, 1)
elif sock.family == socket.AF_INET6:
# IPv6
sock.setsockopt(ipproto_ipv6(), socket.IPV6_JOIN_GROUP, mreq)
# Allow multicast packets to get back on this host
sock.setsockopt(ipproto_ipv6(), socket.IPV6_MULTICAST_LOOP, 1)
return sock, addr_info[4][0]
