Packet library API Reference

Packet class

class ryu.lib.packet.packet.Packet(data=None, protocols=None, parse_cls=<class 'ryu.lib.packet.ethernet.ethernet'>)

A packet decoder/encoder class.

An instance is used to either decode or encode a single packet.

data is a bytearray to describe a raw datagram to decode. When decoding, a Packet object is iteratable. Iterated values are protocol (ethernet, ipv4, ...) headers and the payload. Protocol headers are instances of subclass of packet_base.PacketBase. The payload is a bytearray. They are iterated in on-wire order.

data should be omitted when encoding a packet.

add_protocol(proto)

Register a protocol proto for this packet.

This method is legal only when encoding a packet.

When encoding a packet, register a protocol (ethernet, ipv4, ...) header to add to this packet. Protocol headers should be registered in on-wire order before calling self.serialize.

get_protocol(protocol)

Returns the firstly found protocol that matches to the specified protocol.

get_protocols(protocol)

Returns a list of protocols that matches to the specified protocol.

serialize()

Encode a packet and store the resulted bytearray in self.data.

This method is legal only when encoding a packet.

Stream Parser class

class ryu.lib.packet.stream_parser.StreamParser

Streaming parser base class.

An instance of a subclass of this class is used to extract messages from a raw byte stream.

It’s designed to be used for data read from a transport which doesn’t preserve message boundaries. A typical example of such a transport is TCP.

parse(data)

Tries to extract messages from a raw byte stream.

The data argument would be python bytes newly read from the input stream.

Returns an ordered list of extracted messages. It can be an empty list.

The rest of data which doesn’t produce a complete message is kept internally and will be used when more data is come. I.e. next time this method is called again.

try_parse(q)

Try to extract a message from the given bytes.

This is an override point for subclasses.

This method tries to extract a message from bytes given by the argument.

Raises TooSmallException if the given data is not enough to extract a complete message but there’s still a chance to extract a message if more data is come later.

class ryu.lib.packet.bgp.StreamParser

Streaming parser for BGP-4 messages.

This is a subclass of ryu.lib.packet.stream_parser.StreamParser. Its parse method returns a list of BGPMessage subclass instances.

Protocol Header classes

class ryu.lib.packet.packet_base.PacketBase

A base class for a protocol (ethernet, ipv4, ...) header.

classmethod get_packet_type(type_)

Per-protocol dict-like get method.

Provided for convenience of protocol implementers. Internal use only.

classmethod parser(buf)

Decode a protocol header.

This method is used only when decoding a packet.

Decode a protocol header at offset 0 in bytearray buf. Returns the following three objects.

• An object to describe the decoded header.
• A packet_base.PacketBase subclass appropriate for the rest of the packet. None when the rest of the packet should be considered as raw payload.
• The rest of packet.

classmethod register_packet_type(cls_, type_)

Per-protocol dict-like set method.

Provided for convenience of protocol implementers. Internal use only.

serialize(payload, prev)

Encode a protocol header.

This method is used only when encoding a packet.

Encode a protocol header. Returns a bytearray which contains the header.

payload is the rest of the packet which will immediately follow this header.

prev is a packet_base.PacketBase subclass for the outer protocol header. prev is None if the current header is the outer-most. For example, prev is ipv4 or ipv6 for tcp.serialize.

class ryu.lib.packet.ethernet.ethernet(dst='ff:ff:ff:ff:ff:ff', src='00:00:00:00:00:00', ethertype=2048)

Ethernet header encoder/decoder class.

An instance has the following attributes at least. MAC addresses are represented as a string like ‘08:60:6e:7f:74:e7’. __init__ takes the corresponding args in this order.

Attribute	Description	Example
dst	destination address	‘ff:ff:ff:ff:ff:ff’
src	source address	‘08:60:6e:7f:74:e7’
ethertype	ether type	0x0800

classmethod get_packet_type(type_)

Override method for the ethernet IEEE802.3 Length/Type field (self.ethertype).

If the value of Length/Type field is less than or equal to 1500 decimal(05DC hexadecimal), it means Length interpretation and be passed to the LLC sublayer.

class ryu.lib.packet.vlan.svlan(pcp=0, cfi=0, vid=0, ethertype=33024)

S-VLAN (IEEE 802.1ad) header encoder/decoder class.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
pcp	Priority Code Point
cfi	Canonical Format Indicator. In a case to be used as B-TAG, this field means DEI(Drop Eligible Indication).
vid	VLAN Identifier
ethertype	EtherType

class ryu.lib.packet.vlan.vlan(pcp=0, cfi=0, vid=0, ethertype=2048)

VLAN (IEEE 802.1Q) header encoder/decoder class.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
pcp	Priority Code Point
cfi	Canonical Format Indicator
vid	VLAN Identifier
ethertype	EtherType

classmethod get_packet_type(type_)

Override method for the Length/Type field (self.ethertype). The Length/Type field means Length or Type interpretation, same as ethernet IEEE802.3. If the value of Length/Type field is less than or equal to 1500 decimal(05DC hexadecimal), it means Length interpretation and be passed to the LLC sublayer.

class ryu.lib.packet.pbb.itag(pcp=0, dei=0, uca=0, sid=0)

I-TAG (IEEE 802.1ah-2008) header encoder/decoder class.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
pcp	Priority Code Point
dei	Drop Eligible Indication
uca	Use Customer Address
sid	Service Instance ID

class ryu.lib.packet.mpls.mpls(label=0, exp=0, bsb=1, ttl=255)

MPLS (RFC 3032) header encoder/decoder class.

NOTE: When decoding, this implementation assumes that the inner protocol is IPv4.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
label	Label Value
exp	Experimental Use
bsb	Bottom of Stack
ttl	Time To Live

class ryu.lib.packet.arp.arp(hwtype=1, proto=2048, hlen=6, plen=4, opcode=1, src_mac='ff:ff:ff:ff:ff:ff', src_ip='0.0.0.0', dst_mac='ff:ff:ff:ff:ff:ff', dst_ip='0.0.0.0')

ARP (RFC 826) header encoder/decoder class.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. IPv4 addresses are represented as a string like ‘192.0.2.1’. MAC addresses are represented as a string like ‘08:60:6e:7f:74:e7’. __init__ takes the corresponding args in this order.

Attribute	Description	Example
hwtype	ar$hrd
proto	ar$pro
hlen	ar$hln
plen	ar$pln
opcode	ar$op
src_mac	ar$sha	‘08:60:6e:7f:74:e7’
src_ip	ar$spa	‘192.0.2.1’
dst_mac	ar$tha	‘00:00:00:00:00:00’
dst_ip	ar$tpa	‘192.0.2.2’

ryu.lib.packet.arp.arp_ip(opcode, src_mac, src_ip, dst_mac, dst_ip)

A convenient wrapper for IPv4 ARP for Ethernet.

This is an equivalent of the following code.

arp(ARP_HW_TYPE_ETHERNET, ether.ETH_TYPE_IP, 6, 4, opcode, src_mac, src_ip, dst_mac, dst_ip)

class ryu.lib.packet.ipv4.ipv4(version=4, header_length=5, tos=0, total_length=0, identification=0, flags=0, offset=0, ttl=255, proto=0, csum=0, src='10.0.0.1', dst='10.0.0.2', option=None)

IPv4 (RFC 791) header encoder/decoder class.

NOTE: When decoding, this implementation tries to decode the upper layer protocol even for a fragmented datagram. It isn’t likely what a user would want.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. IPv4 addresses are represented as a string like ‘192.0.2.1’. __init__ takes the corresponding args in this order.

Attribute	Description	Example
version	Version
header_length	IHL
tos	Type of Service
total_length	Total Length (0 means automatically-calculate when encoding)
identification	Identification
flags	Flags
offset	Fragment Offset
ttl	Time to Live
proto	Protocol
csum	Header Checksum (Ignored and automatically-calculated when encoding)
src	Source Address	‘192.0.2.1’
dst	Destination Address	‘192.0.2.2’
option	A bytearray which contains the entire Options, or None for no Options

class ryu.lib.packet.icmp.TimeExceeded(data_len=0, data=None)

ICMP sub encoder/decoder class for Time Exceeded Message.

This is used with ryu.lib.packet.icmp.icmp for ICMP Time Exceeded Message.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

[RFC4884] introduced 8-bit data length attribute.

Attribute	Description
data_len	data length
data	Internet Header + leading octets of original datagram

class ryu.lib.packet.icmp.dest_unreach(data_len=0, mtu=0, data=None)

ICMP sub encoder/decoder class for Destination Unreachable Message.

This is used with ryu.lib.packet.icmp.icmp for ICMP Destination Unreachable Message.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

[RFC1191] reserves bits for the “Next-Hop MTU” field. [RFC4884] introduced 8-bit data length attribute.

Attribute	Description
data_len	data length
mtu	Next-Hop MTU NOTE: This field is required when icmp code is 4 code 4 = fragmentation needed and DF set
data	Internet Header + leading octets of original datagram

class ryu.lib.packet.icmp.echo(id_=0, seq=0, data=None)

ICMP sub encoder/decoder class for Echo and Echo Reply messages.

This is used with ryu.lib.packet.icmp.icmp for ICMP Echo and Echo Reply messages.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
id	Identifier
seq	Sequence Number
data	Internet Header + 64 bits of Original Data Datagram

class ryu.lib.packet.icmp.icmp(type_=8, code=0, csum=0, data=None)

ICMP (RFC 792) header encoder/decoder class.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
type	Type
code	Code
csum	CheckSum (0 means automatically-calculate when encoding)
data	Payload. Either a bytearray, or ryu.lib.packet.icmp.echo or ryu.lib.packet.icmp.dest_unreach or ryu.lib.packet.icmp.TimeExceeded object NOTE for icmp.echo: This includes “unused” 16 bits and the following “Internet Header + 64 bits of Original Data Datagram” of the ICMP header. NOTE for icmp.dest_unreach and icmp.TimeExceeded: This includes “unused” 8 or 24 bits and the following “Internet Header + leading octets of original datagram” of the original packet.

class ryu.lib.packet.ipv6.auth(nxt=6, size=2, spi=0, seq=0, data='x00x00x00x00')

IP Authentication header (RFC 2402) encoder/decoder class.

This is used with ryu.lib.packet.ipv6.ipv6.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
nxt	Next Header
size	the length of the Authentication Header in 64-bit words, subtracting 1.
spi	security parameters index.
seq	sequence number.
data	authentication data.

class ryu.lib.packet.ipv6.dst_opts(nxt=6, size=0, data=None)

IPv6 (RFC 2460) destination header encoder/decoder class.

This is used with ryu.lib.packet.ipv6.ipv6.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
nxt	Next Header
size	the length of the destination header, not include the first 8 octet.
data	IPv6 options.

class ryu.lib.packet.ipv6.fragment(nxt=6, offset=0, more=0, id_=0)

IPv6 (RFC 2460) fragment header encoder/decoder class.

This is used with ryu.lib.packet.ipv6.ipv6.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
nxt	Next Header
offset	offset, in 8-octet units, relative to the start of the fragmentable part of the original packet.
more	1 means more fragments follow; 0 means last fragment.
id_	packet identification value.

class ryu.lib.packet.ipv6.header(nxt)

extension header abstract class.

class ryu.lib.packet.ipv6.hop_opts(nxt=6, size=0, data=None)

IPv6 (RFC 2460) Hop-by-Hop Options header encoder/decoder class.

This is used with ryu.lib.packet.ipv6.ipv6.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
nxt	Next Header
size	the length of the Hop-by-Hop Options header, not include the first 8 octet.
data	IPv6 options.

class ryu.lib.packet.ipv6.ipv6(version=6, traffic_class=0, flow_label=0, payload_length=0, nxt=6, hop_limit=255, src='10::10', dst='20::20', ext_hdrs=None)

IPv6 (RFC 2460) header encoder/decoder class.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. IPv6 addresses are represented as a string like ‘ff02::1’. __init__ takes the corresponding args in this order.

Attribute	Description	Example
version	Version
traffic_class	Traffic Class
flow_label	When decoding, Flow Label. When encoding, the most significant 8 bits of Flow Label.
payload_length	Payload Length
nxt	Next Header
hop_limit	Hop Limit
src	Source Address	‘ff02::1’
dst	Destination Address	‘::’
ext_hdrs	Extension Headers

class ryu.lib.packet.ipv6.opt_header(nxt, size, data)

an abstract class for Hop-by-Hop Options header and destination header.

class ryu.lib.packet.ipv6.option(type_=0, len_=-1, data=None)

IPv6 (RFC 2460) Options header encoder/decoder class.

This is used with ryu.lib.packet.ipv6.hop_opts or

ryu.lib.packet.ipv6.dst_opts.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
type_	option type.
len_	the length of data. -1 if type_ is 0.
data	an option value. None if len_ is 0 or -1.

class ryu.lib.packet.ipv6.routing(nxt)

An IPv6 Routing Header decoder class. This class has only the parser method.

IPv6 Routing Header types.

http://www.iana.org/assignments/ipv6-parameters/ipv6-parameters.xhtml

Value	Description	Reference
0	Source Route (DEPRECATED)	[[IPV6]][RFC5095]
1	Nimrod (DEPRECATED 2009-05-06)
2	Type 2 Routing Header	[RFC6275]
3	RPL Source Route Header	[RFC6554]
4 - 252	Unassigned
253	RFC3692-style Experiment 1 [2]	[RFC4727]
254	RFC3692-style Experiment 2 [2]	[RFC4727]
255	Reserved

class ryu.lib.packet.ipv6.routing_type3(nxt=6, size=0, type_=3, seg=0, cmpi=0, cmpe=0, adrs=None)

An IPv6 Routing Header for Source Routes with the RPL (RFC 6554) encoder/decoder class.

This is used with ryu.lib.packet.ipv6.ipv6.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
nxt	Next Header
size	The length of the Routing header, not include the first 8 octet. (0 means automatically-calculate when encoding)
type	Identifies the particular Routing header variant.
seg	Number of route segments remaining.
cmpi	Number of prefix octets from segments 1 through n-1.
cmpe	Number of prefix octets from segment n.
pad	Number of octets that are used for padding after Address[n] at the end of the SRH.
adrs	Vector of addresses, numbered 1 to n.

class ryu.lib.packet.icmpv6.echo(id_=0, seq=0, data=None)

ICMPv6 sub encoder/decoder class for Echo Request and Echo Reply messages.

This is used with ryu.lib.packet.icmpv6.icmpv6 for ICMPv6 Echo Request and Echo Reply messages.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
id	Identifier
seq	Sequence Number
data	Data

class ryu.lib.packet.icmpv6.icmpv6(type_=0, code=0, csum=0, data=None)

ICMPv6 (RFC 2463) header encoder/decoder class.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
type_	Type
code	Code
csum	CheckSum (0 means automatically-calculate when encoding)
data	Payload. ryu.lib.packet.icmpv6.echo object, ryu.lib.packet.icmpv6.nd_neighbor object, ryu.lib.packet.icmpv6.nd_router_solicit object, ryu.lib.packet.icmpv6.nd_router_advert object, ryu.lib.packet.icmpv6.mld object, or a bytearray.

class ryu.lib.packet.icmpv6.mld(maxresp=0, address='::')

ICMPv6 sub encoder/decoder class for MLD Lister Query, MLD Listener Report, and MLD Listener Done messages. (RFC 2710)

http://www.ietf.org/rfc/rfc2710.txt

This is used with ryu.lib.packet.icmpv6.icmpv6.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
maxresp	max response time in millisecond. it is meaningful only in Query Message.
address	a group address value.

class ryu.lib.packet.icmpv6.mldv2_query(maxresp=0, address='::', s_flg=0, qrv=2, qqic=0, num=0, srcs=None)

ICMPv6 sub encoder/decoder class for MLD v2 Lister Query messages. (RFC 3810)

http://www.ietf.org/rfc/rfc3810.txt

This is used with ryu.lib.packet.icmpv6.icmpv6.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
maxresp	max response time in millisecond. it is meaningful only in Query Message.
address	a group address value.
s_flg	when set to 1, routers suppress the timer process.
qrv	robustness variable for a querier.
qqic	an interval time for a querier in unit of seconds.
num	a number of the multicast servers.
srcs	a list of IPv6 addresses of the multicast servers.

class ryu.lib.packet.icmpv6.mldv2_report(record_num=0, records=None)

ICMPv6 sub encoder/decoder class for MLD v2 Lister Report messages. (RFC 3810)

http://www.ietf.org/rfc/rfc3810.txt

This is used with ryu.lib.packet.icmpv6.icmpv6.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
record_num	a number of the group records.
records	a list of ryu.lib.packet.icmpv6.mldv2_report_group. None if no records.

class ryu.lib.packet.icmpv6.mldv2_report_group(type_=0, aux_len=0, num=0, address='::', srcs=None, aux=None)

ICMPv6 sub encoder/decoder class for MLD v2 Lister Report Group Record messages. (RFC 3810)

This is used with ryu.lib.packet.icmpv6.mldv2_report.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
type_	a group record type for v3.
aux_len	the length of the auxiliary data in 32-bit words.
num	a number of the multicast servers.
address	a group address value.
srcs	a list of IPv6 addresses of the multicast servers.
aux	the auxiliary data.

class ryu.lib.packet.icmpv6.nd_neighbor(res=0, dst='::', option=None)

ICMPv6 sub encoder/decoder class for Neighbor Solicitation and Neighbor Advertisement messages. (RFC 4861)

This is used with ryu.lib.packet.icmpv6.icmpv6.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
res	R,S,O Flags for Neighbor Advertisement. The 3 MSBs of “Reserved” field for Neighbor Solicitation.
dst	Target Address
option	a derived object of ryu.lib.packet.icmpv6.nd_option or a bytearray. None if no options.

class ryu.lib.packet.icmpv6.nd_option_pi(length=0, pl=0, res1=0, val_l=0, pre_l=0, res2=0, prefix='::')

ICMPv6 sub encoder/decoder class for Neighbor discovery Prefix Information Option. (RFC 4861)

This is used with ryu.lib.packet.icmpv6.nd_router_advert.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
length	length of the option. (0 means automatically-calculate when encoding)
pl	Prefix Length.
res1	L,A,R* Flags for Prefix Information.
val_l	Valid Lifetime.
pre_l	Preferred Lifetime.
res2	This field is unused. It MUST be initialized to zero.
prefix	An IP address or a prefix of an IP address.

*R flag is defined in (RFC 3775)

class ryu.lib.packet.icmpv6.nd_option_sla(length=0, hw_src='00:00:00:00:00:00', data=None)

ICMPv6 sub encoder/decoder class for Neighbor discovery Source Link-Layer Address Option. (RFC 4861)

This is used with ryu.lib.packet.icmpv6.nd_neighbor, ryu.lib.packet.icmpv6.nd_router_solicit or ryu.lib.packet.icmpv6.nd_router_advert.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
length	length of the option. (0 means automatically-calculate when encoding)
hw_src	Link-Layer Address. NOTE: If the address is longer than 6 octets this contains the first 6 octets in the address. This implementation assumes the address has at least 6 octets.
data	A bytearray which contains the rest of Link-Layer Address and padding. When encoding a packet, it’s user’s responsibility to provide necessary padding for 8-octets alignment required by the protocol.

class ryu.lib.packet.icmpv6.nd_option_tla(length=0, hw_src='00:00:00:00:00:00', data=None)

ICMPv6 sub encoder/decoder class for Neighbor discovery Target Link-Layer Address Option. (RFC 4861)

This is used with ryu.lib.packet.icmpv6.nd_neighbor.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
length	length of the option. (0 means automatically-calculate when encoding)
hw_src	Link-Layer Address. NOTE: If the address is longer than 6 octets this contains the first 6 octets in the address. This implementation assumes the address has at least 6 octets.
data	A bytearray which contains the rest of Link-Layer Address and padding. When encoding a packet, it’s user’s responsibility to provide necessary padding for 8-octets alignment required by the protocol.

class ryu.lib.packet.icmpv6.nd_router_advert(ch_l=0, res=0, rou_l=0, rea_t=0, ret_t=0, options=None)

ICMPv6 sub encoder/decoder class for Router Advertisement messages. (RFC 4861)

This is used with ryu.lib.packet.icmpv6.icmpv6.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
ch_l	Cur Hop Limit.
res	M,O Flags for Router Advertisement.
rou_l	Router Lifetime.
rea_t	Reachable Time.
ret_t	Retrans Timer.
options	List of a derived object of ryu.lib.packet.icmpv6.nd_option or a bytearray. None if no options.

class ryu.lib.packet.icmpv6.nd_router_solicit(res=0, option=None)

ICMPv6 sub encoder/decoder class for Router Solicitation messages. (RFC 4861)

This is used with ryu.lib.packet.icmpv6.icmpv6.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
res	This field is unused. It MUST be initialized to zero.
option	a derived object of ryu.lib.packet.icmpv6.nd_option or a bytearray. None if no options.

class ryu.lib.packet.tcp.tcp(src_port=1, dst_port=1, seq=0, ack=0, offset=0, bits=0, window_size=0, csum=0, urgent=0, option=None)

TCP (RFC 793) header encoder/decoder class.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
src_port	Source Port
dst_port	Destination Port
seq	Sequence Number
ack	Acknowledgement Number
offset	Data Offset (0 means automatically-calculate when encoding)
bits	Control Bits
window_size	Window
csum	Checksum (0 means automatically-calculate when encoding)
urgent	Urgent Pointer
option	An bytearray containing Options and following Padding. None if no options.

class ryu.lib.packet.udp.udp(src_port=1, dst_port=1, total_length=0, csum=0)

UDP (RFC 768) header encoder/decoder class.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
src_port	Source Port
dst_port	Destination Port
total_length	Length (0 means automatically-calculate when encoding)
csum	Checksum (0 means automatically-calculate when encoding)

class ryu.lib.packet.dhcp.dhcp(op, chaddr, options, htype=1, hlen=0, hops=0, xid=None, secs=0, flags=0, ciaddr='0.0.0.0', yiaddr='0.0.0.0', siaddr='0.0.0.0', giaddr='0.0.0.0', sname='', boot_file='')

DHCP (RFC 2131) header encoder/decoder class.

The serialized packet would looks like the ones described in the following sections.

• RFC 2131 DHCP packet format

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
op	Message op code / message type. 1 = BOOTREQUEST, 2 = BOOTREPLY
htype	Hardware address type (e.g. ‘1’ = 10mb ethernet).
hlen	Hardware address length (e.g. ‘6’ = 10mb ethernet).
hops	Client sets to zero, optionally used by relay agent when booting via a relay agent.
xid	Transaction ID, a random number chosen by the client, used by the client and serverto associate messages and responses between a client and a server.
secs	Filled in by client, seconds elapsed since client began address acquisition or renewal process.
flags	Flags.
ciaddr	Client IP address; only filled in if client is in BOUND, RENEW or REBINDING state and can respond to ARP requests.
yiaddr	‘your’ (client) IP address.
siaddr	IP address of next server to use in bootstrap; returned in DHCPOFFER, DHCPACK by server.
giaddr	Relay agent IP address, used in booting via a relay agent.
chaddr	Client hardware address.
sname	Optional server host name, null terminated string.
boot_file	Boot file name, null terminated string; “generic” name or null in DHCPDISCOVER, fully qualified directory-path name in DHCPOFFER.
options	Optional parameters field (‘DHCP message type’ option must be included in every DHCP message).

class ryu.lib.packet.dhcp.options(option_list=None, options_len=0, magic_cookie='99.130.83.99')

DHCP (RFC 2132) options encoder/decoder class.

This is used with ryu.lib.packet.dhcp.dhcp.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
option_list	‘end option’ and ‘pad option’ are added automatically after the option class is stored in array.
options_len	Option’s byte length. (‘magic cookie’, ‘end option’ and ‘pad option’ length including.)
magic_cookie	The first four octets contain the decimal values 99, 130, 83 and 99.

class ryu.lib.packet.dhcp.option(tag, value, length=0)

DHCP (RFC 2132) options encoder/decoder class.

This is used with ryu.lib.packet.dhcp.dhcp.options.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
tag	Option type. (except for the ‘magic cookie’, ‘pad option’ and ‘end option’.)
value	Option’s value. (set the value that has been converted to hexadecimal.)
length	Option’s value length. (calculated automatically from the length of value.)

class ryu.lib.packet.vrrp.vrrp(version, type_, vrid, priority, count_ip, max_adver_int, checksum, ip_addresses, auth_type=None, auth_data=None)

The base class for VRRPv2 (RFC 3768) and VRRPv3 (RFC 5798) header encoder/decoder classes.

Unlike other ryu.lib.packet.packet_base.PacketBase derived classes, This class should not be directly instantiated by user.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order.

Attribute	Description
version	Version
type	Type
vrid	Virtual Rtr ID (VRID)
priority	Priority
count_ip	Count IPvX Addr. Calculated automatically when encoding.
max_adver_int	Maximum Advertisement Interval (Max Adver Int)
checksum	Checksum. Calculated automatically when encoding.
ip_addresses	IPvX Address(es). A python list of IP addresses.
auth_type	Authentication Type (only for VRRPv2)
auth_data	Authentication Data (only for VRRPv2)

create_packet(primary_ip_address, vlan_id=None)

Prepare a VRRP packet.

Returns a newly created ryu.lib.packet.packet.Packet object with appropriate protocol header objects added by add_protocol(). It’s caller’s responsibility to serialize(). The serialized packet would looks like the ones described in the following sections.

• RFC 3768 5.1. VRRP Packet Format
• RFC 5798 5.1. VRRP Packet Format

Argument	Description
primary_ip_address	Source IP address
vlan_id	VLAN ID. None for no VLAN.

class ryu.lib.packet.vrrp.vrrpv2(version, type_, vrid, priority, count_ip, max_adver_int, checksum, ip_addresses, auth_type=None, auth_data=None)

VRRPv2 (RFC 3768) header encoder/decoder class.

Unlike other ryu.lib.packet.packet_base.PacketBase derived classes, create method should be used to instantiate an object of this class.

static create(type_, vrid, priority, max_adver_int, ip_addresses)

Unlike other ryu.lib.packet.packet_base.PacketBase derived classes, this method should be used to instantiate an object of this class.

This method’s arguments are same as ryu.lib.packet.vrrp.vrrp object’s attributes of the same name. (except that type_ corresponds to type attribute.)

class ryu.lib.packet.vrrp.vrrpv3(version, type_, vrid, priority, count_ip, max_adver_int, checksum, ip_addresses, auth_type=None, auth_data=None)

VRRPv3 (RFC 5798) header encoder/decoder class.

Unlike other ryu.lib.packet.packet_base.PacketBase derived classes, create method should be used to instantiate an object of this class.

static create(type_, vrid, priority, max_adver_int, ip_addresses)

Unlike other ryu.lib.packet.packet_base.PacketBase derived classes, this method should be used to instantiate an object of this class.

This method’s arguments are same as ryu.lib.packet.vrrp.vrrp object’s attributes of the same name. (except that type_ corresponds to type attribute.)

class ryu.lib.packet.slow.slow

Slow Protocol header decoder class. This class has only the parser method.

http://standards.ieee.org/getieee802/download/802.3-2012_section5.pdf

Slow Protocols Subtypes

Subtype Value	Protocol Name
0	Unused - Illegal Value
1	Link Aggregation Control Protocol(LACP)
2	Link Aggregation - Marker Protocol
3	Operations, Administration, and Maintenance(OAM)
4 - 9	Reserved for future use
10	Organization Specific Slow Protocol(OSSP)
11 - 255	Unused - Illegal values

class ryu.lib.packet.slow.lacp(version=1, actor_system_priority=0, actor_system='00:00:00:00:00:00', actor_key=0, actor_port_priority=0, actor_port=0, actor_state_activity=0, actor_state_timeout=0, actor_state_aggregation=0, actor_state_synchronization=0, actor_state_collecting=0, actor_state_distributing=0, actor_state_defaulted=0, actor_state_expired=0, partner_system_priority=0, partner_system='00:00:00:00:00:00', partner_key=0, partner_port_priority=0, partner_port=0, partner_state_activity=0, partner_state_timeout=0, partner_state_aggregation=0, partner_state_synchronization=0, partner_state_collecting=0, partner_state_distributing=0, partner_state_defaulted=0, partner_state_expired=0, collector_max_delay=0)

Link Aggregation Control Protocol(LACP, IEEE 802.1AX) header encoder/decoder class.

http://standards.ieee.org/getieee802/download/802.1AX-2008.pdf

LACPDU format

LACPDU structure		Octets
Subtype = LACP		1
Version Number		1
TLV Actor	TLV_type = Actor Information	1
	Actor_Information_Length = 20	1
	Actor_System_Priority	2
	Actor_System	6
	Actor_Key	2
	Actor_Port_Priority	2
	Actor_Port	2
	Actor_State	1
	Reserved	3
TLV Partner	TLV_type = Partner Information	1
	Partner_Information_Length = 20	1
	Partner_System_Priority	2
	Partner_System	6
	Partner_Key	2
	Partner_Port_Priority	2
	Partner_Port	2
	Partner_State	1
	Reserved	3
TLV Collector	TLV_type = Collector Information	1
	Collector_Information_Length = 16	1
	Collector_Max_Delay	2
	Reserved	12
TLV Terminator	TLV_type = Terminator	1
	Terminator_Length = 0	1
	Reserved	50

Terminator information uses a length value of 0 (0x00).

NOTE–The use of a Terminator_Length of 0 is intentional.

In TLV encoding schemes it is common practice for the terminator encoding to be 0 both for the type and the length.

Actor_State and Partner_State encoded as individual bits within a single octet as follows:

7	6	5	4	3	2	1	0
EXPR	DFLT	DIST	CLCT	SYNC	AGGR	TMO	ACT

ACT

bit 0. about the activity control value with regard to this link.

TMO

bit 1. about the timeout control value with regard to this link.

AGGR

bit 2. about how the system regards this link from the point of view of the aggregation.

SYNC

bit 3. about how the system regards this link from the point of view of the synchronization.

CLCT

bit 4. about collecting of incoming frames.

DIST

bit 5. about distributing of outgoing frames.

DFLT

bit 6. about the opposite system information which the system use.

EXPR

bit 7. about the expire state of the system.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
version	LACP version. This parameter must be set to LACP_VERSION_NUMBER(i.e. 1).
actor_system_priority	The priority assigned to this System.
actor_system	The Actor’s System ID, encoded as a MAC address.
actor_key	The operational Key value assigned to the port by the Actor.
actor_port_priority	The priority assigned to this port.
actor_port	The port number assigned to the port by the Actor.
actor_state_activity	about the activity control value with regard to this link. LACP_STATE_ACTIVE(1) LACP_STATE_PASSIVE(0)
actor_state_timeout	about the timeout control value with regard to this link. LACP_STATE_SHORT_TIMEOUT(1) LACP_STATE_LONG_TIMEOUT(0)
actor_state_aggregation	about how the system regards this link from the point of view of the aggregation. LACP_STATE_AGGREGATEABLE(1) LACP_STATE_INDIVIDUAL(0)
actor_state_synchronization	about how the system regards this link from the point of view of the synchronization. LACP_STATE_IN_SYNC(1) LACP_STATE_OUT_OF_SYNC(0)
actor_state_collecting	about collecting of incoming frames. LACP_STATE_COLLECTING_ENABLED(1) LACP_STATE_COLLECTING_DISABLED(0)
actor_state_distributing	about distributing of outgoing frames. LACP_STATE_DISTRIBUTING_ENABLED(1) LACP_STATE_DISTRIBUTING_DISABLED(0)
actor_state_defaulted	about the Partner information which the the Actor use. LACP_STATE_DEFAULTED_PARTNER(1) LACP_STATE_OPERATIONAL_PARTNER(0)
actor_state_expired	about the state of the Actor. LACP_STATE_EXPIRED(1) LACP_STATE_NOT_EXPIRED(0)
partner_system_priority	The priority assigned to the Partner System.
partner_system	The Partner’s System ID, encoded as a MAC address.
partner_key	The operational Key value assigned to the port by the Partner.
partner_port_priority	The priority assigned to this port by the Partner.
partner_port	The port number assigned to the port by the Partner.
partner_state_activity	See actor_state_activity.
partner_state_timeout	See actor_state_timeout.
partner_state_aggregation	See actor_state_aggregation.
partner_state_synchronization	See actor_state_synchronization.
partner_state_collecting	See actor_state_collecting.
partner_state_distributing	See actor_state_distributing.
partner_state_defaulted	See actor_state_defaulted.
partner_state_expired	See actor_state_expired.
collector_max_delay	the maximum time that the Frame Collector may delay.

class ryu.lib.packet.llc.llc(dsap_addr, ssap_addr, control)

LLC(IEEE 802.2) header encoder/decoder class.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
dsap_addr	Destination service access point address field includes I/G bit at least significant bit.
ssap_addr	Source service access point address field includes C/R bit at least significant bit.
control	Control field [16 bits for formats that include sequence numbering, and 8 bits for formats that do not]. Either ryu.lib.packet.llc.ControlFormatI or ryu.lib.packet.llc.ControlFormatS or ryu.lib.packet.llc.ControlFormatU object.

class ryu.lib.packet.llc.ControlFormatI(send_sequence_number=0, pf_bit=0, receive_sequence_number=0)

LLC sub encoder/decoder class for control I-format field.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
send_sequence_number	sender send sequence number
pf_bit	poll/final bit
receive_sequence_number	sender receive sequence number

class ryu.lib.packet.llc.ControlFormatS(supervisory_function=0, pf_bit=0, receive_sequence_number=0)

LLC sub encoder/decoder class for control S-format field.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
supervisory_function	supervisory function bit
pf_bit	poll/final bit
receive_sequence_number	sender receive sequence number

class ryu.lib.packet.llc.ControlFormatU(modifier_function1=0, pf_bit=0, modifier_function2=0)

LLC sub encoder/decoder class for control U-format field.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
modifier_function1	modifier function bit
pf_bit	poll/final bit
modifier_function2	modifier function bit

class ryu.lib.packet.bpdu.bpdu

Bridge Protocol Data Unit(BPDU) header encoder/decoder base class.

class ryu.lib.packet.bpdu.ConfigurationBPDUs(flags=0, root_priority=32768, root_system_id_extension=0, root_mac_address='00:00:00:00:00:00', root_path_cost=0, bridge_priority=32768, bridge_system_id_extension=0, bridge_mac_address='00:00:00:00:00:00', port_priority=128, port_number=0, message_age=0, max_age=20, hello_time=2, forward_delay=15)

Configuration BPDUs(IEEE 802.1D) header encoder/decoder class.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
flags	Bit 1: Topology Change flag Bits 2 through 7: unused and take the value 0 Bit 8: Topology Change Acknowledgment flag
root_priority	Root Identifier priority set 0-61440 in steps of 4096
root_system_id_extension	Root Identifier system ID extension
root_mac_address	Root Identifier MAC address
root_path_cost	Root Path Cost
bridge_priority	Bridge Identifier priority set 0-61440 in steps of 4096
bridge_system_id_extension	Bridge Identifier system ID extension
bridge_mac_address	Bridge Identifier MAC address
port_priority	Port Identifier priority set 0-240 in steps of 16
port_number	Port Identifier number
message_age	Message Age timer value
max_age	Max Age timer value
hello_time	Hello Time timer value
forward_delay	Forward Delay timer value

class ryu.lib.packet.bpdu.TopologyChangeNotificationBPDUs

Topology Change Notification BPDUs(IEEE 802.1D) header encoder/decoder class.

class ryu.lib.packet.bpdu.RstBPDUs(flags=0, root_priority=32768, root_system_id_extension=0, root_mac_address='00:00:00:00:00:00', root_path_cost=0, bridge_priority=32768, bridge_system_id_extension=0, bridge_mac_address='00:00:00:00:00:00', port_priority=128, port_number=0, message_age=0, max_age=20, hello_time=2, forward_delay=15)

Rapid Spanning Tree BPDUs(RST BPDUs, IEEE 802.1D) header encoder/decoder class.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
flags	Bit 1: Topology Change flag Bit 2: Proposal flag Bits 3 and 4: Port Role Bit 5: Learning flag Bit 6: Forwarding flag Bit 7: Agreement flag Bit 8: Topology Change Acknowledgment flag
root_priority	Root Identifier priority set 0-61440 in steps of 4096
root_system_id_extension	Root Identifier system ID extension
root_mac_address	Root Identifier MAC address
root_path_cost	Root Path Cost
bridge_priority	Bridge Identifier priority set 0-61440 in steps of 4096
bridge_system_id_extension	Bridge Identifier system ID extension
bridge_mac_address	Bridge Identifier MAC address
port_priority	Port Identifier priority set 0-240 in steps of 16
port_number	Port Identifier number
message_age	Message Age timer value
max_age	Max Age timer value
hello_time	Hello Time timer value
forward_delay	Forward Delay timer value

class ryu.lib.packet.igmp.igmp(msgtype=17, maxresp=0, csum=0, address='0.0.0.0')

Internet Group Management Protocol(IGMP, RFC 1112, RFC 2236) header encoder/decoder class.

http://www.ietf.org/rfc/rfc1112.txt

http://www.ietf.org/rfc/rfc2236.txt

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
msgtype	a message type for v2, or a combination of version and a message type for v1.
maxresp	max response time in unit of 1/10 second. it is meaningful only in Query Message.
csum	a check sum value. 0 means automatically-calculate when encoding.
address	a group address value.

class ryu.lib.packet.bgp.BGPMessage(type_, len_=None, marker=None)

Base class for BGP-4 messages.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
marker	Marker field. Ignored when encoding.
len	Length field. Ignored when encoding.
type	Type field. one of BGP_MSG_ constants.

class ryu.lib.packet.bgp.BGPOpen(my_as, bgp_identifier, type_=1, opt_param_len=0, opt_param=[], version=4, hold_time=0, len_=None, marker=None)

BGP-4 OPEN Message encoder/decoder class.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
marker	Marker field. Ignored when encoding.
len	Length field. Ignored when encoding.
type	Type field. The default is BGP_MSG_OPEN.
version	Version field. The default is 4.
my_as	My Autonomous System field. 2 octet unsigned integer.
hold_time	Hold Time field. 2 octet unsigned integer. The default is 0.
bgp_identifier	BGP Identifier field. An IPv4 address. For example, ‘192.0.2.1’
opt_param_len	Optional Parameters Length field. Ignored when encoding.
opt_param	Optional Parameters field. A list of BGPOptParam instances. The default is [].

class ryu.lib.packet.bgp.BGPUpdate(type_=2, withdrawn_routes_len=None, withdrawn_routes=[], total_path_attribute_len=None, path_attributes=[], nlri=[], len_=None, marker=None)

BGP-4 UPDATE Message encoder/decoder class.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
marker	Marker field. Ignored when encoding.
len	Length field. Ignored when encoding.
type	Type field. The default is BGP_MSG_UPDATE.
withdrawn_routes_len	Withdrawn Routes Length field. Ignored when encoding.
withdrawn_routes	Withdrawn Routes field. A list of BGPWithdrawnRoute instances. The default is [].
total_path_attribute_len	Total Path Attribute Length field. Ignored when encoding.
path_attributes	Path Attributes field. A list of BGPPathAttribute instances. The default is [].
nlri	Network Layer Reachability Information field. A list of BGPNLRI instances. The default is [].

class ryu.lib.packet.bgp.BGPKeepAlive(type_=4, len_=None, marker=None)

BGP-4 KEEPALIVE Message encoder/decoder class.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
marker	Marker field. Ignored when encoding.
len	Length field. Ignored when encoding.
type	Type field. The default is BGP_MSG_KEEPALIVE.

class ryu.lib.packet.bgp.BGPNotification(error_code, error_subcode, data='', type_=3, len_=None, marker=None)

BGP-4 NOTIFICATION Message encoder/decoder class.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
marker	Marker field. Ignored when encoding.
len	Length field. Ignored when encoding.
type	Type field. The default is BGP_MSG_NOTIFICATION.
error_code	Error code field.
error_subcode	Error subcode field.
data	Data field. The default is ‘’.

class ryu.lib.packet.sctp.cause_cookie_while_shutdown(length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Cookie Received While Shutting Down (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_abort and

ryu.lib.packet.sctp.chunk_error.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
length	length of this cause containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.cause_invalid_param(length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Invalid Mandatory Parameter (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_abort and

ryu.lib.packet.sctp.chunk_error.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
length	length of this cause containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.cause_invalid_stream_id(value=0, length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Invalid Stream Identifier (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_abort and

ryu.lib.packet.sctp.chunk_error.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
value	stream id.
length	length of this cause containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.cause_missing_param(types=None, num=0, length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Missing Mandatory Parameter (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_abort and

ryu.lib.packet.sctp.chunk_error.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
types	a list of missing params.
num	Number of missing params. (0 means automatically-calculate when encoding)
length	length of this cause containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.cause_no_userdata(value=None, length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for No User Data (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_abort and

ryu.lib.packet.sctp.chunk_error.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
value	the TSN of the DATA chunk received with no user data field.
length	length of this cause containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.cause_out_of_resource(length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Out of Resource (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_abort and

ryu.lib.packet.sctp.chunk_error.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
length	length of this cause containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.cause_protocol_violation(value=None, length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Protocol Violation (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_abort and

ryu.lib.packet.sctp.chunk_error.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
value	Additional Information.
length	length of this cause containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.cause_restart_with_new_addr(value=None, length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Restart of an Association with New Addresses (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_abort and

ryu.lib.packet.sctp.chunk_error.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
value	New Address TLVs.
length	length of this cause containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.cause_stale_cookie(value=None, length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Stale Cookie Error (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_abort and

ryu.lib.packet.sctp.chunk_error.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
value	Measure of Staleness.
length	length of this cause containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.cause_unrecognized_chunk(value=None, length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Unrecognized Chunk Type (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_abort and

ryu.lib.packet.sctp.chunk_error.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
value	Unrecognized Chunk.
length	length of this cause containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.cause_unrecognized_param(value=None, length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Unrecognized Parameters (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_abort and

ryu.lib.packet.sctp.chunk_error.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
value	Unrecognized Parameter.
length	length of this cause containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.cause_unresolvable_addr(value=None, length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Unresolvable Address (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_abort and

ryu.lib.packet.sctp.chunk_error.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
value	Unresolvable Address. one of follows: ryu.lib.packet.sctp.param_host_addr, ryu.lib.packet.sctp.param_ipv4, or ryu.lib.packet.sctp.param_ipv6.
length	length of this cause containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.cause_user_initiated_abort(value=None, length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for User-Initiated Abort (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_abort and

ryu.lib.packet.sctp.chunk_error.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
value	Upper Layer Abort Reason.
length	length of this cause containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.chunk_abort(tflag=0, length=0, causes=None)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Abort Association (ABORT) chunk (RFC 4960).

This is used with ryu.lib.packet.sctp.sctp.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
tflag	‘0’ means the Verification tag is normal. ‘1’ means the Verification tag is copy of the sender.
length	length of this chunk containing this header. (0 means automatically-calculate when encoding)
causes	a list of derived classes of ryu.lib.packet.sctp.causes.

class ryu.lib.packet.sctp.chunk_cookie_ack(flags=0, length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Cookie Acknowledgement (COOKIE ACK) chunk (RFC 4960).

This is used with ryu.lib.packet.sctp.sctp.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
flags	set to ‘0’. this field will be ignored.
length	length of this chunk containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.chunk_cookie_echo(flags=0, length=0, cookie=None)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Cookie Echo (COOKIE ECHO) chunk (RFC 4960).

This is used with ryu.lib.packet.sctp.sctp.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
flags	set to ‘0’. this field will be ignored.
length	length of this chunk containing this header. (0 means automatically-calculate when encoding)
cookie	cookie data.

class ryu.lib.packet.sctp.chunk_cwr(flags=0, length=0, low_tsn=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for CWR chunk (RFC 4960 Appendix A.).

This is used with ryu.lib.packet.sctp.sctp.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
flags	set to ‘0’. this field will be ignored.
length	length of this chunk containing this header. (0 means automatically-calculate when encoding)
low_tsn	the lowest TSN.

class ryu.lib.packet.sctp.chunk_data(unordered=0, begin=0, end=0, length=0, tsn=0, sid=0, seq=0, payload_id=0, payload_data=None)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Payload Data (DATA) chunk (RFC 4960).

This is used with ryu.lib.packet.sctp.sctp.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
unordered	if set to ‘1’, the receiver ignores the sequence number.
begin	if set to ‘1’, this chunk is the first fragment.
end	if set to ‘1’, this chunk is the last fragment.
length	length of this chunk containing this header. (0 means automatically-calculate when encoding)
tsn	Transmission Sequence Number.
sid	stream id.
seq	the sequence number.
payload_id	application specified protocol id. ‘0’ means that no application id is identified.
payload_data	user data.

class ryu.lib.packet.sctp.chunk_ecn_echo(flags=0, length=0, low_tsn=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for ECN-Echo chunk (RFC 4960 Appendix A.).

This is used with ryu.lib.packet.sctp.sctp.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
flags	set to ‘0’. this field will be ignored.
length	length of this chunk containing this header. (0 means automatically-calculate when encoding)
low_tsn	the lowest TSN.

class ryu.lib.packet.sctp.chunk_error(flags=0, length=0, causes=None)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Operation Error (ERROR) chunk (RFC 4960).

This is used with ryu.lib.packet.sctp.sctp.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
flags	set to ‘0’. this field will be ignored.
length	length of this chunk containing this header. (0 means automatically-calculate when encoding)
causes	a list of derived classes of ryu.lib.packet.sctp.causes.

class ryu.lib.packet.sctp.chunk_heartbeat(flags=0, length=0, info=None)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Heartbeat Request (HEARTBEAT) chunk (RFC 4960).

This is used with ryu.lib.packet.sctp.sctp.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
flags	set to ‘0’. this field will be ignored.
length	length of this chunk containing this header. (0 means automatically-calculate when encoding)
info	ryu.lib.packet.sctp.param_heartbeat.

class ryu.lib.packet.sctp.chunk_heartbeat_ack(flags=0, length=0, info=None)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Heartbeat Acknowledgement (HEARTBEAT ACK) chunk (RFC 4960).

This is used with ryu.lib.packet.sctp.sctp.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
flags	set to ‘0’. this field will be ignored.
length	length of this chunk containing this header. (0 means automatically-calculate when encoding)
info	ryu.lib.packet.sctp.param_heartbeat.

class ryu.lib.packet.sctp.chunk_init(flags=0, length=0, init_tag=0, a_rwnd=0, os=0, mis=0, i_tsn=0, params=None)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Initiation (INIT) chunk (RFC 4960).

This is used with ryu.lib.packet.sctp.sctp.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
flags	set to ‘0’. this field will be ignored.
length	length of this chunk containing this header. (0 means automatically-calculate when encoding)
init_tag	the tag that be used as Verification Tag.
a_rwnd	Advertised Receiver Window Credit.
os	number of outbound streams.
mis	number of inbound streams.
i_tsn	Transmission Sequence Number that the sender will use.
params	Optional/Variable-Length Parameters. a list of derived classes of ryu.lib.packet.sctp.param.

class ryu.lib.packet.sctp.chunk_init_ack(flags=0, length=0, init_tag=0, a_rwnd=0, os=0, mis=0, i_tsn=0, params=None)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Initiation Acknowledgement (INIT ACK) chunk (RFC 4960).

This is used with ryu.lib.packet.sctp.sctp.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
flags	set to ‘0’. this field will be ignored.
length	length of this chunk containing this header. (0 means automatically-calculate when encoding)
init_tag	the tag that be used as Verification Tag.
a_rwnd	Advertised Receiver Window Credit.
os	number of outbound streams.
mis	number of inbound streams.
i_tsn	Transmission Sequence Number that the sender will use.
params	Optional/Variable-Length Parameters. a list of derived classes of ryu.lib.packet.sctp.param.

class ryu.lib.packet.sctp.chunk_sack(flags=0, length=0, tsn_ack=0, a_rwnd=0, gapack_num=0, duptsn_num=0, gapacks=None, duptsns=None)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Selective Acknowledgement (SACK) chunk (RFC 4960).

This is used with ryu.lib.packet.sctp.sctp.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
flags	set to ‘0’. this field will be ignored.
length	length of this chunk containing this header. (0 means automatically-calculate when encoding)
tsn_ack	TSN of the last DATA chunk received in sequence before a gap.
a_rwnd	Advertised Receiver Window Credit.
gapack_num	number of Gap Ack blocks.
duptsn_num	number of duplicate TSNs.
gapacks	a list of Gap Ack blocks. one block is made of a list with the start offset and the end offset from tsn_ack. e.g.) gapacks = [[2, 3], [10, 12], [19, 21]]
duptsns	a list of duplicate TSN.

class ryu.lib.packet.sctp.chunk_shutdown(flags=0, length=0, tsn_ack=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Shutdown Association (SHUTDOWN) chunk (RFC 4960).

This is used with ryu.lib.packet.sctp.sctp.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
flags	set to ‘0’. this field will be ignored.
length	length of this chunk containing this header. (0 means automatically-calculate when encoding)
tsn_ack	TSN of the last DATA chunk received in sequence before a gap.

class ryu.lib.packet.sctp.chunk_shutdown_ack(flags=0, length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Shutdown Acknowledgement (SHUTDOWN ACK) chunk (RFC 4960).

This is used with ryu.lib.packet.sctp.sctp.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
flags	set to ‘0’. this field will be ignored.
length	length of this chunk containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.chunk_shutdown_complete(tflag=0, length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Shutdown Complete (SHUTDOWN COMPLETE) chunk (RFC 4960).

This is used with ryu.lib.packet.sctp.sctp.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
tflag	‘0’ means the Verification tag is normal. ‘1’ means the Verification tag is copy of the sender.
length	length of this chunk containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.param_cookie_preserve(value=0, length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Cookie Preservative Parameter (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_init.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
value	Suggested Cookie Life-Span Increment (msec).
length	length of this param containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.param_ecn(value=None, length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for ECN Parameter (RFC 4960 Appendix A.).

This is used with ryu.lib.packet.sctp.chunk_init and

ryu.lib.packet.sctp.chunk_init_ack.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
value	set to None.
length	length of this param containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.param_heartbeat(value=None, length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Heartbeat Info Parameter (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_heartbeat and

ryu.lib.packet.sctp.chunk_heartbeat_ack.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
value	the sender-specific heartbeat information.
length	length of this param containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.param_host_addr(value=None, length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Host Name Address Parameter (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_init and

ryu.lib.packet.sctp.chunk_init_ack.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
value	a host name that ends with null terminator.
length	length of this param containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.param_ipv4(value='127.0.0.1', length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for IPv4 Address Parameter (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_init and

ryu.lib.packet.sctp.chunk_init_ack.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
value	IPv4 address of the sending endpoint.
length	length of this param containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.param_ipv6(value='::1', length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for IPv6 Address Parameter (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_init and

ryu.lib.packet.sctp.chunk_init_ack.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
value	IPv6 address of the sending endpoint.
length	length of this param containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.param_state_cookie(value=None, length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for State Cookie Parameter (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_init_ack.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
value	the state cookie. see Section 5.1.3 in RFC 4960.
length	length of this param containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.param_supported_addr(value=None, length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Supported Address Types Parameter (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_init.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
value	a list of parameter types. odd cases pad with 0x0000.
length	length of this param containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.param_unrecognized_param(value=None, length=0)

Stream Control Transmission Protocol (SCTP) sub encoder/decoder class for Unrecognized Parameter (RFC 4960).

This is used with ryu.lib.packet.sctp.chunk_init_ack.

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
value	the unrecognized parameter in the INIT chunk.
length	length of this param containing this header. (0 means automatically-calculate when encoding)

class ryu.lib.packet.sctp.sctp(src_port=1, dst_port=1, vtag=0, csum=0, chunks=None)

Stream Control Transmission Protocol (SCTP) header encoder/decoder class (RFC 4960).

An instance has the following attributes at least. Most of them are same to the on-wire counterparts but in host byte order. __init__ takes the corresponding args in this order.

Attribute	Description
src_port	Source Port
dst_port	Destination Port
vtag	Verification Tag
csum	Checksum (0 means automatically-calculate when encoding)
chunks	a list of derived classes of ryu.lib.packet.sctp.chunk.