# This file is part of Scapy # See http://www.secdev.org/projects/scapy for more information # Copyright (C) Philippe Biondi # Copyright (C) 6WIND # This program is published under a GPLv2 license """ SCTP (Stream Control Transmission Protocol). """ from __future__ import absolute_import import struct from scapy.compat import orb, raw from scapy.volatile import RandBin from scapy.config import conf from scapy.packet import Packet, bind_layers from scapy.fields import BitField, ByteEnumField, ConditionalField, Field, \ FieldLenField, FieldListField, IPField, IntEnumField, IntField, \ PacketListField, PadField, ShortEnumField, ShortField, StrLenField, \ XByteField, XIntField, XShortField from scapy.layers.inet import IP from scapy.layers.inet6 import IP6Field from scapy.layers.inet6 import IPv6 IPPROTO_SCTP = 132 # crc32-c (Castagnoli) (crc32c_poly=0x1EDC6F41) crc32c_table = [ 0x00000000, 0xF26B8303, 0xE13B70F7, 0x1350F3F4, 0xC79A971F, 0x35F1141C, 0x26A1E7E8, 0xD4CA64EB, 0x8AD958CF, 0x78B2DBCC, 0x6BE22838, 0x9989AB3B, 0x4D43CFD0, 0xBF284CD3, 0xAC78BF27, 0x5E133C24, 0x105EC76F, 0xE235446C, 0xF165B798, 0x030E349B, 0xD7C45070, 0x25AFD373, 0x36FF2087, 0xC494A384, 0x9A879FA0, 0x68EC1CA3, 0x7BBCEF57, 0x89D76C54, 0x5D1D08BF, 0xAF768BBC, 0xBC267848, 0x4E4DFB4B, 0x20BD8EDE, 0xD2D60DDD, 0xC186FE29, 0x33ED7D2A, 0xE72719C1, 0x154C9AC2, 0x061C6936, 0xF477EA35, 0xAA64D611, 0x580F5512, 0x4B5FA6E6, 0xB93425E5, 0x6DFE410E, 0x9F95C20D, 0x8CC531F9, 0x7EAEB2FA, 0x30E349B1, 0xC288CAB2, 0xD1D83946, 0x23B3BA45, 0xF779DEAE, 0x05125DAD, 0x1642AE59, 0xE4292D5A, 0xBA3A117E, 0x4851927D, 0x5B016189, 0xA96AE28A, 0x7DA08661, 0x8FCB0562, 0x9C9BF696, 0x6EF07595, 0x417B1DBC, 0xB3109EBF, 0xA0406D4B, 0x522BEE48, 0x86E18AA3, 0x748A09A0, 0x67DAFA54, 0x95B17957, 0xCBA24573, 0x39C9C670, 0x2A993584, 0xD8F2B687, 0x0C38D26C, 0xFE53516F, 0xED03A29B, 0x1F682198, 0x5125DAD3, 0xA34E59D0, 0xB01EAA24, 0x42752927, 0x96BF4DCC, 0x64D4CECF, 0x77843D3B, 0x85EFBE38, 0xDBFC821C, 0x2997011F, 0x3AC7F2EB, 0xC8AC71E8, 0x1C661503, 0xEE0D9600, 0xFD5D65F4, 0x0F36E6F7, 0x61C69362, 0x93AD1061, 0x80FDE395, 0x72966096, 0xA65C047D, 0x5437877E, 0x4767748A, 0xB50CF789, 0xEB1FCBAD, 0x197448AE, 0x0A24BB5A, 0xF84F3859, 0x2C855CB2, 0xDEEEDFB1, 0xCDBE2C45, 0x3FD5AF46, 0x7198540D, 0x83F3D70E, 0x90A324FA, 0x62C8A7F9, 0xB602C312, 0x44694011, 0x5739B3E5, 0xA55230E6, 0xFB410CC2, 0x092A8FC1, 0x1A7A7C35, 0xE811FF36, 0x3CDB9BDD, 0xCEB018DE, 0xDDE0EB2A, 0x2F8B6829, 0x82F63B78, 0x709DB87B, 0x63CD4B8F, 0x91A6C88C, 0x456CAC67, 0xB7072F64, 0xA457DC90, 0x563C5F93, 0x082F63B7, 0xFA44E0B4, 0xE9141340, 0x1B7F9043, 0xCFB5F4A8, 0x3DDE77AB, 0x2E8E845F, 0xDCE5075C, 0x92A8FC17, 0x60C37F14, 0x73938CE0, 0x81F80FE3, 0x55326B08, 0xA759E80B, 0xB4091BFF, 0x466298FC, 0x1871A4D8, 0xEA1A27DB, 0xF94AD42F, 0x0B21572C, 0xDFEB33C7, 0x2D80B0C4, 0x3ED04330, 0xCCBBC033, 0xA24BB5A6, 0x502036A5, 0x4370C551, 0xB11B4652, 0x65D122B9, 0x97BAA1BA, 0x84EA524E, 0x7681D14D, 0x2892ED69, 0xDAF96E6A, 0xC9A99D9E, 0x3BC21E9D, 0xEF087A76, 0x1D63F975, 0x0E330A81, 0xFC588982, 0xB21572C9, 0x407EF1CA, 0x532E023E, 0xA145813D, 0x758FE5D6, 0x87E466D5, 0x94B49521, 0x66DF1622, 0x38CC2A06, 0xCAA7A905, 0xD9F75AF1, 0x2B9CD9F2, 0xFF56BD19, 0x0D3D3E1A, 0x1E6DCDEE, 0xEC064EED, 0xC38D26C4, 0x31E6A5C7, 0x22B65633, 0xD0DDD530, 0x0417B1DB, 0xF67C32D8, 0xE52CC12C, 0x1747422F, 0x49547E0B, 0xBB3FFD08, 0xA86F0EFC, 0x5A048DFF, 0x8ECEE914, 0x7CA56A17, 0x6FF599E3, 0x9D9E1AE0, 0xD3D3E1AB, 0x21B862A8, 0x32E8915C, 0xC083125F, 0x144976B4, 0xE622F5B7, 0xF5720643, 0x07198540, 0x590AB964, 0xAB613A67, 0xB831C993, 0x4A5A4A90, 0x9E902E7B, 0x6CFBAD78, 0x7FAB5E8C, 0x8DC0DD8F, 0xE330A81A, 0x115B2B19, 0x020BD8ED, 0xF0605BEE, 0x24AA3F05, 0xD6C1BC06, 0xC5914FF2, 0x37FACCF1, 0x69E9F0D5, 0x9B8273D6, 0x88D28022, 0x7AB90321, 0xAE7367CA, 0x5C18E4C9, 0x4F48173D, 0xBD23943E, 0xF36E6F75, 0x0105EC76, 0x12551F82, 0xE03E9C81, 0x34F4F86A, 0xC69F7B69, 0xD5CF889D, 0x27A40B9E, 0x79B737BA, 0x8BDCB4B9, 0x988C474D, 0x6AE7C44E, 0xBE2DA0A5, 0x4C4623A6, 0x5F16D052, 0xAD7D5351, ] def crc32c(buf): crc = 0xffffffff for c in buf: crc = (crc >> 8) ^ crc32c_table[(crc ^ (orb(c))) & 0xFF] crc = (~crc) & 0xffffffff # reverse endianness return struct.unpack(">I", struct.pack("> 16) & 0xffff print s1,s2 for c in buf: print orb(c) s1 = (s1 + orb(c)) % BASE s2 = (s2 + s1) % BASE print s1,s2 return (s2 << 16) + s1 def sctp_checksum(buf): return update_adler32(1, buf) """ hmactypes = { 0: "Reserved1", 1: "SHA-1", 2: "Reserved2", 3: "SHA-256", } sctpchunktypescls = { 0: "SCTPChunkData", 1: "SCTPChunkInit", 2: "SCTPChunkInitAck", 3: "SCTPChunkSACK", 4: "SCTPChunkHeartbeatReq", 5: "SCTPChunkHeartbeatAck", 6: "SCTPChunkAbort", 7: "SCTPChunkShutdown", 8: "SCTPChunkShutdownAck", 9: "SCTPChunkError", 10: "SCTPChunkCookieEcho", 11: "SCTPChunkCookieAck", 14: "SCTPChunkShutdownComplete", 15: "SCTPChunkAuthentication", 0x80: "SCTPChunkAddressConfAck", 0xc1: "SCTPChunkAddressConf", } sctpchunktypes = { 0: "data", 1: "init", 2: "init-ack", 3: "sack", 4: "heartbeat-req", 5: "heartbeat-ack", 6: "abort", 7: "shutdown", 8: "shutdown-ack", 9: "error", 10: "cookie-echo", 11: "cookie-ack", 14: "shutdown-complete", 15: "authentication", 0x80: "address-configuration-ack", 0xc1: "address-configuration", } sctpchunkparamtypescls = { 1: "SCTPChunkParamHearbeatInfo", 5: "SCTPChunkParamIPv4Addr", 6: "SCTPChunkParamIPv6Addr", 7: "SCTPChunkParamStateCookie", 8: "SCTPChunkParamUnrocognizedParam", 9: "SCTPChunkParamCookiePreservative", 11: "SCTPChunkParamHostname", 12: "SCTPChunkParamSupportedAddrTypes", 0x8000: "SCTPChunkParamECNCapable", 0x8002: "SCTPChunkParamRandom", 0x8003: "SCTPChunkParamChunkList", 0x8004: "SCTPChunkParamRequestedHMACFunctions", 0x8008: "SCTPChunkParamSupportedExtensions", 0xc000: "SCTPChunkParamFwdTSN", 0xc001: "SCTPChunkParamAddIPAddr", 0xc002: "SCTPChunkParamDelIPAddr", 0xc003: "SCTPChunkParamErrorIndication", 0xc004: "SCTPChunkParamSetPrimaryAddr", 0xc005: "SCTPChunkParamSuccessIndication", 0xc006: "SCTPChunkParamAdaptationLayer", } sctpchunkparamtypes = { 1: "heartbeat-info", 5: "IPv4", 6: "IPv6", 7: "state-cookie", 8: "unrecognized-param", 9: "cookie-preservative", 11: "hostname", 12: "addrtypes", 0x8000: "ecn-capable", 0x8002: "random", 0x8003: "chunk-list", 0x8004: "requested-HMAC-functions", 0x8008: "supported-extensions", 0xc000: "fwd-tsn-supported", 0xc001: "add-IP", 0xc002: "del-IP", 0xc003: "error-indication", 0xc004: "set-primary-addr", 0xc005: "success-indication", 0xc006: "adaptation-layer", } # SCTP header # Dummy class to guess payload type (variable parameters) class _SCTPChunkGuessPayload: def default_payload_class(self, p): if len(p) < 4: return conf.padding_layer else: t = orb(p[0]) return globals().get(sctpchunktypescls.get(t, "Raw"), conf.raw_layer) # noqa: E501 class SCTP(_SCTPChunkGuessPayload, Packet): fields_desc = [ShortField("sport", None), ShortField("dport", None), XIntField("tag", None), XIntField("chksum", None), ] def answers(self, other): if not isinstance(other, SCTP): return 0 if conf.checkIPsrc: if not ((self.sport == other.dport) and (self.dport == other.sport)): return 0 return 1 def post_build(self, p, pay): p += pay if self.chksum is None: crc = crc32c(raw(p)) p = p[:8] + struct.pack(">I", crc) + p[12:] return p # SCTP Chunk variable params class ChunkParamField(PacketListField): def __init__(self, name, default, count_from=None, length_from=None): PacketListField.__init__(self, name, default, conf.raw_layer, count_from=count_from, length_from=length_from) # noqa: E501 def m2i(self, p, m): cls = conf.raw_layer if len(m) >= 4: t = orb(m[0]) * 256 + orb(m[1]) cls = globals().get(sctpchunkparamtypescls.get(t, "Raw"), conf.raw_layer) # noqa: E501 return cls(m) # dummy class to avoid Raw() after Chunk params class _SCTPChunkParam: def extract_padding(self, s): return b"", s[:] class SCTPChunkParamHearbeatInfo(_SCTPChunkParam, Packet): fields_desc = [ShortEnumField("type", 1, sctpchunkparamtypes), FieldLenField("len", None, length_of="data", adjust=lambda pkt, x:x + 4), PadField(StrLenField("data", "", length_from=lambda pkt: pkt.len - 4), 4, padwith=b"\x00"), ] class SCTPChunkParamIPv4Addr(_SCTPChunkParam, Packet): fields_desc = [ShortEnumField("type", 5, sctpchunkparamtypes), ShortField("len", 8), IPField("addr", "127.0.0.1"), ] class SCTPChunkParamIPv6Addr(_SCTPChunkParam, Packet): fields_desc = [ShortEnumField("type", 6, sctpchunkparamtypes), ShortField("len", 20), IP6Field("addr", "::1"), ] class SCTPChunkParamStateCookie(_SCTPChunkParam, Packet): fields_desc = [ShortEnumField("type", 7, sctpchunkparamtypes), FieldLenField("len", None, length_of="cookie", adjust=lambda pkt, x:x + 4), PadField(StrLenField("cookie", "", length_from=lambda pkt: pkt.len - 4), 4, padwith=b"\x00"), ] class SCTPChunkParamUnrocognizedParam(_SCTPChunkParam, Packet): fields_desc = [ShortEnumField("type", 8, sctpchunkparamtypes), FieldLenField("len", None, length_of="param", adjust=lambda pkt, x:x + 4), PadField(StrLenField("param", "", length_from=lambda pkt: pkt.len - 4), 4, padwith=b"\x00"), ] class SCTPChunkParamCookiePreservative(_SCTPChunkParam, Packet): fields_desc = [ShortEnumField("type", 9, sctpchunkparamtypes), ShortField("len", 8), XIntField("sug_cookie_inc", None), ] class SCTPChunkParamHostname(_SCTPChunkParam, Packet): fields_desc = [ShortEnumField("type", 11, sctpchunkparamtypes), FieldLenField("len", None, length_of="hostname", adjust=lambda pkt, x:x + 4), PadField(StrLenField("hostname", "", length_from=lambda pkt: pkt.len - 4), 4, padwith=b"\x00"), ] class SCTPChunkParamSupportedAddrTypes(_SCTPChunkParam, Packet): fields_desc = [ShortEnumField("type", 12, sctpchunkparamtypes), FieldLenField("len", None, length_of="addr_type_list", adjust=lambda pkt, x:x + 4), PadField(FieldListField("addr_type_list", ["IPv4"], ShortEnumField("addr_type", 5, sctpchunkparamtypes), # noqa: E501 length_from=lambda pkt: pkt.len - 4), # noqa: E501 4, padwith=b"\x00"), ] class SCTPChunkParamECNCapable(_SCTPChunkParam, Packet): fields_desc = [ShortEnumField("type", 0x8000, sctpchunkparamtypes), ShortField("len", 4), ] class SCTPChunkParamRandom(_SCTPChunkParam, Packet): fields_desc = [ShortEnumField("type", 0x8002, sctpchunkparamtypes), FieldLenField("len", None, length_of="random", adjust=lambda pkt, x:x + 4), PadField(StrLenField("random", RandBin(32), length_from=lambda pkt: pkt.len - 4), 4, padwith=b"\x00"), ] class SCTPChunkParamChunkList(_SCTPChunkParam, Packet): fields_desc = [ShortEnumField("type", 0x8003, sctpchunkparamtypes), FieldLenField("len", None, length_of="chunk_list", adjust=lambda pkt, x:x + 4), PadField(FieldListField("chunk_list", None, ByteEnumField("chunk", None, sctpchunktypes), # noqa: E501 length_from=lambda pkt: pkt.len - 4), # noqa: E501 4, padwith=b"\x00"), ] class SCTPChunkParamRequestedHMACFunctions(_SCTPChunkParam, Packet): fields_desc = [ShortEnumField("type", 0x8004, sctpchunkparamtypes), FieldLenField("len", None, length_of="HMAC_functions_list", adjust=lambda pkt, x:x + 4), PadField(FieldListField("HMAC_functions_list", ["SHA-1"], ShortEnumField("HMAC_function", 1, hmactypes), # noqa: E501 length_from=lambda pkt: pkt.len - 4), # noqa: E501 4, padwith=b"\x00"), ] class SCTPChunkParamSupportedExtensions(_SCTPChunkParam, Packet): fields_desc = [ShortEnumField("type", 0x8008, sctpchunkparamtypes), FieldLenField("len", None, length_of="supported_extensions", adjust=lambda pkt, x:x + 4), PadField(FieldListField("supported_extensions", ["authentication", "address-configuration", "address-configuration-ack"], ByteEnumField("supported_extensions", # noqa: E501 None, sctpchunktypes), length_from=lambda pkt: pkt.len - 4), # noqa: E501 4, padwith=b"\x00"), ] class SCTPChunkParamFwdTSN(_SCTPChunkParam, Packet): fields_desc = [ShortEnumField("type", 0xc000, sctpchunkparamtypes), ShortField("len", 4), ] class SCTPChunkParamAddIPAddr(_SCTPChunkParam, Packet): fields_desc = [ShortEnumField("type", 0xc001, sctpchunkparamtypes), FieldLenField("len", None, length_of="addr", adjust=lambda pkt, x:x + 12), XIntField("correlation_id", None), ShortEnumField("addr_type", 5, sctpchunkparamtypes), FieldLenField("addr_len", None, length_of="addr", adjust=lambda pkt, x:x + 4), ConditionalField( IPField("addr", "127.0.0.1"), lambda p: p.addr_type == 5), ConditionalField( IP6Field("addr", "::1"), lambda p: p.addr_type == 6), ] class SCTPChunkParamDelIPAddr(SCTPChunkParamAddIPAddr): type = 0xc002 class SCTPChunkParamErrorIndication(_SCTPChunkParam, Packet): fields_desc = [ShortEnumField("type", 0xc003, sctpchunkparamtypes), FieldLenField("len", None, length_of="error_causes", adjust=lambda pkt, x:x + 8), XIntField("correlation_id", None), PadField(StrLenField("error_causes", "", length_from=lambda pkt: pkt.len - 4), 4, padwith=b"\x00"), ] class SCTPChunkParamSetPrimaryAddr(SCTPChunkParamAddIPAddr): type = 0xc004 class SCTPChunkParamSuccessIndication(_SCTPChunkParam, Packet): fields_desc = [ShortEnumField("type", 0xc005, sctpchunkparamtypes), ShortField("len", 8), XIntField("correlation_id", None), ] class SCTPChunkParamAdaptationLayer(_SCTPChunkParam, Packet): fields_desc = [ShortEnumField("type", 0xc006, sctpchunkparamtypes), ShortField("len", 8), XIntField("indication", None), ] # SCTP Chunks # Dictionary taken from: http://www.iana.org/assignments/sctp-parameters/sctp-parameters.xhtml # noqa: E501 SCTP_PAYLOAD_PROTOCOL_INDENTIFIERS = { 0: 'Reserved', 1: 'IUA', 2: 'M2UA', 3: 'M3UA', 4: 'SUA', 5: 'M2PA', 6: 'V5UA', 7: 'H.248', 8: 'BICC/Q.2150.3', 9: 'TALI', 10: 'DUA', 11: 'ASAP', 12: 'ENRP', 13: 'H.323', 14: 'Q.IPC/Q.2150.3', 15: 'SIMCO', 16: 'DDP Segment Chunk', 17: 'DDP Stream Session Control', 18: 'S1AP', 19: 'RUA', 20: 'HNBAP', 21: 'ForCES-HP', 22: 'ForCES-MP', 23: 'ForCES-LP', 24: 'SBc-AP', 25: 'NBAP', 26: 'Unassigned', 27: 'X2AP', 28: 'IRCP', 29: 'LCS-AP', 30: 'MPICH2', 31: 'SABP', 32: 'FGP', 33: 'PPP', 34: 'CALCAPP', 35: 'SSP', 36: 'NPMP-CONTROL', 37: 'NPMP-DATA', 38: 'ECHO', 39: 'DISCARD', 40: 'DAYTIME', 41: 'CHARGEN', 42: '3GPP RNA', 43: '3GPP M2AP', 44: '3GPP M3AP', 45: 'SSH/SCTP', 46: 'Diameter/SCTP', 47: 'Diameter/DTLS/SCTP', 48: 'R14P', 49: 'Unassigned', 50: 'WebRTC DCEP', 51: 'WebRTC String', 52: 'WebRTC Binary Partial', 53: 'WebRTC Binary', 54: 'WebRTC String Partial', 55: '3GPP PUA', 56: 'WebRTC String Empty', 57: 'WebRTC Binary Empty' } class SCTPChunkData(_SCTPChunkGuessPayload, Packet): # TODO : add a padding function in post build if this layer is used to generate SCTP chunk data # noqa: E501 fields_desc = [ByteEnumField("type", 0, sctpchunktypes), BitField("reserved", None, 4), BitField("delay_sack", 0, 1), BitField("unordered", 0, 1), BitField("beginning", 0, 1), BitField("ending", 0, 1), FieldLenField("len", None, length_of="data", adjust=lambda pkt, x:x + 16), # noqa: E501 XIntField("tsn", None), XShortField("stream_id", None), XShortField("stream_seq", None), IntEnumField("proto_id", None, SCTP_PAYLOAD_PROTOCOL_INDENTIFIERS), # noqa: E501 PadField(StrLenField("data", None, length_from=lambda pkt: pkt.len - 16), # noqa: E501 4, padwith=b"\x00"), ] class SCTPChunkInit(_SCTPChunkGuessPayload, Packet): fields_desc = [ByteEnumField("type", 1, sctpchunktypes), XByteField("flags", None), FieldLenField("len", None, length_of="params", adjust=lambda pkt, x:x + 20), # noqa: E501 XIntField("init_tag", None), IntField("a_rwnd", None), ShortField("n_out_streams", None), ShortField("n_in_streams", None), XIntField("init_tsn", None), ChunkParamField("params", None, length_from=lambda pkt:pkt.len - 20), # noqa: E501 ] class SCTPChunkInitAck(SCTPChunkInit): type = 2 class GapAckField(Field): def __init__(self, name, default): Field.__init__(self, name, default, "4s") def i2m(self, pkt, x): if x is None: return b"\0\0\0\0" sta, end = [int(e) for e in x.split(':')] args = tuple([">HH", sta, end]) return struct.pack(*args) def m2i(self, pkt, x): return "%d:%d" % (struct.unpack(">HH", x)) def any2i(self, pkt, x): if isinstance(x, tuple) and len(x) == 2: return "%d:%d" % (x) return x class SCTPChunkSACK(_SCTPChunkGuessPayload, Packet): fields_desc = [ByteEnumField("type", 3, sctpchunktypes), XByteField("flags", None), ShortField("len", None), XIntField("cumul_tsn_ack", None), IntField("a_rwnd", None), FieldLenField("n_gap_ack", None, count_of="gap_ack_list"), FieldLenField("n_dup_tsn", None, count_of="dup_tsn_list"), FieldListField("gap_ack_list", [], GapAckField("gap_ack", None), count_from=lambda pkt:pkt.n_gap_ack), # noqa: E501 FieldListField("dup_tsn_list", [], XIntField("dup_tsn", None), count_from=lambda pkt:pkt.n_dup_tsn), # noqa: E501 ] def post_build(self, p, pay): if self.len is None: p = p[:2] + struct.pack(">H", len(p)) + p[4:] return p + pay class SCTPChunkHeartbeatReq(_SCTPChunkGuessPayload, Packet): fields_desc = [ByteEnumField("type", 4, sctpchunktypes), XByteField("flags", None), FieldLenField("len", None, length_of="params", adjust=lambda pkt, x:x + 4), # noqa: E501 ChunkParamField("params", None, length_from=lambda pkt:pkt.len - 4), # noqa: E501 ] class SCTPChunkHeartbeatAck(SCTPChunkHeartbeatReq): type = 5 class SCTPChunkAbort(_SCTPChunkGuessPayload, Packet): fields_desc = [ByteEnumField("type", 6, sctpchunktypes), BitField("reserved", None, 7), BitField("TCB", 0, 1), FieldLenField("len", None, length_of="error_causes", adjust=lambda pkt, x:x + 4), # noqa: E501 PadField(StrLenField("error_causes", "", length_from=lambda pkt: pkt.len - 4), # noqa: E501 4, padwith=b"\x00"), ] class SCTPChunkShutdown(_SCTPChunkGuessPayload, Packet): fields_desc = [ByteEnumField("type", 7, sctpchunktypes), XByteField("flags", None), ShortField("len", 8), XIntField("cumul_tsn_ack", None), ] class SCTPChunkShutdownAck(_SCTPChunkGuessPayload, Packet): fields_desc = [ByteEnumField("type", 8, sctpchunktypes), XByteField("flags", None), ShortField("len", 4), ] class SCTPChunkError(_SCTPChunkGuessPayload, Packet): fields_desc = [ByteEnumField("type", 9, sctpchunktypes), XByteField("flags", None), FieldLenField("len", None, length_of="error_causes", adjust=lambda pkt, x:x + 4), # noqa: E501 PadField(StrLenField("error_causes", "", length_from=lambda pkt: pkt.len - 4), # noqa: E501 4, padwith=b"\x00"), ] class SCTPChunkCookieEcho(SCTPChunkError): fields_desc = [ByteEnumField("type", 10, sctpchunktypes), XByteField("flags", None), FieldLenField("len", None, length_of="cookie", adjust=lambda pkt, x:x + 4), # noqa: E501 PadField(StrLenField("cookie", "", length_from=lambda pkt: pkt.len - 4), # noqa: E501 4, padwith=b"\x00"), ] class SCTPChunkCookieAck(_SCTPChunkGuessPayload, Packet): fields_desc = [ByteEnumField("type", 11, sctpchunktypes), XByteField("flags", None), ShortField("len", 4), ] class SCTPChunkShutdownComplete(_SCTPChunkGuessPayload, Packet): fields_desc = [ByteEnumField("type", 14, sctpchunktypes), BitField("reserved", None, 7), BitField("TCB", 0, 1), ShortField("len", 4), ] class SCTPChunkAuthentication(_SCTPChunkGuessPayload, Packet): fields_desc = [ByteEnumField("type", 15, sctpchunktypes), XByteField("flags", None), FieldLenField("len", None, length_of="HMAC", adjust=lambda pkt, x:x + 8), ShortField("shared_key_id", None), ShortField("HMAC_function", None), PadField(StrLenField("HMAC", "", length_from=lambda pkt: pkt.len - 8), # noqa: E501 4, padwith=b"\x00"), ] class SCTPChunkAddressConf(_SCTPChunkGuessPayload, Packet): fields_desc = [ByteEnumField("type", 0xc1, sctpchunktypes), XByteField("flags", None), FieldLenField("len", None, length_of="params", adjust=lambda pkt, x:x + 8), IntField("seq", 0), ChunkParamField("params", None, length_from=lambda pkt:pkt.len - 8), # noqa: E501 ] class SCTPChunkAddressConfAck(SCTPChunkAddressConf): type = 0x80 bind_layers(IP, SCTP, proto=IPPROTO_SCTP) bind_layers(IPv6, SCTP, nh=IPPROTO_SCTP)