1# Copyright (C) 2014 Nippon Telegraph and Telephone Corporation. 2# Copyright (C) 2014 YAMAMOTO Takashi <yamamoto at valinux co jp> 3# 4# Licensed under the Apache License, Version 2.0 (the "License"); 5# you may not use this file except in compliance with the License. 6# You may obtain a copy of the License at 7# 8# http://www.apache.org/licenses/LICENSE-2.0 9# 10# Unless required by applicable law or agreed to in writing, software 11# distributed under the License is distributed on an "AS IS" BASIS, 12# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or 13# implied. 14# See the License for the specific language governing permissions and 15# limitations under the License. 16 17import platform 18import socket 19import struct 20 21from ryu.lib import addrconv 22 23 24system = platform.system() 25if system == 'Linux': 26 # on linux, 27 # no ss_len 28 # u16 ss_family 29 _HDR_FMT = "H" 30 _HAVE_SS_LEN = False 31else: 32 # assume 33 # u8 ss_len 34 # u8 ss_family 35 _HDR_FMT = "BB" 36 _HAVE_SS_LEN = True 37 38 39# RFC 2553 40_SS_MAXSIZE = 128 41_SS_ALIGNSIZE = 8 42 43_SIN_SIZE = 16 # sizeof(struct sockaddr_in) 44 45_HDR_LEN = struct.calcsize(_HDR_FMT) 46 47 48def _hdr(ss_len, af): 49 if _HAVE_SS_LEN: 50 return struct.pack(_HDR_FMT, ss_len, af) 51 else: 52 return struct.pack(_HDR_FMT, af) 53 54 55def _pad_to(data, total_len): 56 pad_len = total_len - len(data) 57 return data + pad_len * '\0' 58 59 60def sa_in4(addr, port=0): 61 data = struct.pack("!H4s", port, addrconv.ipv4.text_to_bin(addr)) 62 hdr = _hdr(_SIN_SIZE, socket.AF_INET) 63 return _pad_to(hdr + data, _SIN_SIZE) 64 65 66def sa_in6(addr, port=0, flowinfo=0, scope_id=0): 67 data = struct.pack("!HI16sI", port, flowinfo, 68 addrconv.ipv6.text_to_bin(addr), scope_id) 69 hdr = _hdr(_HDR_LEN + len(data), socket.AF_INET6) 70 return hdr + data 71 72 73def sa_to_ss(sa): 74 return _pad_to(sa, _SS_MAXSIZE) 75