include/net/sctp/constants.h - kernel/msm-4.19 - Gitiles

 /* SCTP kernel implementation
  * (C) Copyright IBM Corp. 2001, 2004
  * Copyright (c) 1999-2000 Cisco, Inc.
  * Copyright (c) 1999-2001 Motorola, Inc.
  * Copyright (c) 2001 Intel Corp.
  *
  * This file is part of the SCTP kernel implementation
  *
  * This SCTP implementation is free software;
  * you can redistribute it and/or modify it under the terms of
  * the GNU General Public License as published by
  * the Free Software Foundation; either version 2, or (at your option)
  * any later version.
  *
  * This SCTP implementation is distributed in the hope that it
  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  *                 ************************
  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  * See the GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with GNU CC; see the file COPYING.  If not, see
  * <http://www.gnu.org/licenses/>.
  *
  * Please send any bug reports or fixes you make to the
  * email address(es):
  *    lksctp developers <linux-sctp@vger.kernel.org>
  *
  * Written or modified by:
  *   La Monte H.P. Yarroll <piggy@acm.org>
  *   Karl Knutson          <karl@athena.chicago.il.us>
  *   Randall Stewart       <randall@stewart.chicago.il.us>
  *   Ken Morneau           <kmorneau@cisco.com>
  *   Qiaobing Xie          <qxie1@motorola.com>
  *   Xingang Guo           <xingang.guo@intel.com>
  *   Sridhar Samudrala     <samudrala@us.ibm.com>
  *   Daisy Chang           <daisyc@us.ibm.com>
  */

 #ifndef __sctp_constants_h__
 #define __sctp_constants_h__

 #include <linux/sctp.h>
 #include <linux/ipv6.h> /* For ipv6hdr. */
 #include <net/tcp_states.h>  /* For TCP states used in enum sctp_sock_state */

 /* Value used for stream negotiation. */
 enum { SCTP_MAX_STREAM = 0xffff };
 enum { SCTP_DEFAULT_OUTSTREAMS = 10 };
 enum { SCTP_DEFAULT_INSTREAMS = SCTP_MAX_STREAM };

 /* Since CIDs are sparse, we need all four of the following
  * symbols.  CIDs are dense through SCTP_CID_BASE_MAX.
  */
 #define SCTP_CID_BASE_MAX		SCTP_CID_SHUTDOWN_COMPLETE

 #define SCTP_NUM_BASE_CHUNK_TYPES	(SCTP_CID_BASE_MAX + 1)

 #define SCTP_NUM_ADDIP_CHUNK_TYPES	2

 #define SCTP_NUM_PRSCTP_CHUNK_TYPES	1

 #define SCTP_NUM_RECONF_CHUNK_TYPES	1

 #define SCTP_NUM_AUTH_CHUNK_TYPES	1

 #define SCTP_NUM_CHUNK_TYPES		(SCTP_NUM_BASE_CHUNK_TYPES + \
 					 SCTP_NUM_ADDIP_CHUNK_TYPES +\
 					 SCTP_NUM_PRSCTP_CHUNK_TYPES +\
 					 SCTP_NUM_RECONF_CHUNK_TYPES +\
 					 SCTP_NUM_AUTH_CHUNK_TYPES)

 /* These are the different flavours of event.  */
 typedef enum {

 	SCTP_EVENT_T_CHUNK = 1,
 	SCTP_EVENT_T_TIMEOUT,
 	SCTP_EVENT_T_OTHER,
 	SCTP_EVENT_T_PRIMITIVE

 } sctp_event_t;

 /* As a convenience for the state machine, we append SCTP_EVENT_* and
  * SCTP_ULP_* to the list of possible chunks.
  */

 typedef enum {
 	SCTP_EVENT_TIMEOUT_NONE = 0,
 	SCTP_EVENT_TIMEOUT_T1_COOKIE,
 	SCTP_EVENT_TIMEOUT_T1_INIT,
 	SCTP_EVENT_TIMEOUT_T2_SHUTDOWN,
 	SCTP_EVENT_TIMEOUT_T3_RTX,
 	SCTP_EVENT_TIMEOUT_T4_RTO,
 	SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD,
 	SCTP_EVENT_TIMEOUT_HEARTBEAT,
 	SCTP_EVENT_TIMEOUT_RECONF,
 	SCTP_EVENT_TIMEOUT_SACK,
 	SCTP_EVENT_TIMEOUT_AUTOCLOSE,
 } sctp_event_timeout_t;

 #define SCTP_EVENT_TIMEOUT_MAX		SCTP_EVENT_TIMEOUT_AUTOCLOSE
 #define SCTP_NUM_TIMEOUT_TYPES		(SCTP_EVENT_TIMEOUT_MAX + 1)

 typedef enum {
 	SCTP_EVENT_NO_PENDING_TSN = 0,
 	SCTP_EVENT_ICMP_PROTO_UNREACH,
 } sctp_event_other_t;

 #define SCTP_EVENT_OTHER_MAX		SCTP_EVENT_ICMP_PROTO_UNREACH
 #define SCTP_NUM_OTHER_TYPES		(SCTP_EVENT_OTHER_MAX + 1)

 /* These are primitive requests from the ULP.  */
 typedef enum {
 	SCTP_PRIMITIVE_ASSOCIATE = 0,
 	SCTP_PRIMITIVE_SHUTDOWN,
 	SCTP_PRIMITIVE_ABORT,
 	SCTP_PRIMITIVE_SEND,
 	SCTP_PRIMITIVE_REQUESTHEARTBEAT,
 	SCTP_PRIMITIVE_ASCONF,
 	SCTP_PRIMITIVE_RECONF,
 } sctp_event_primitive_t;

 #define SCTP_EVENT_PRIMITIVE_MAX	SCTP_PRIMITIVE_RECONF
 #define SCTP_NUM_PRIMITIVE_TYPES	(SCTP_EVENT_PRIMITIVE_MAX + 1)

 /* We define here a utility type for manipulating subtypes.
  * The subtype constructors all work like this:
  *
  * 	sctp_subtype_t foo = SCTP_ST_CHUNK(SCTP_CID_INIT);
  */

 typedef union {
 	enum sctp_cid chunk;
 	sctp_event_timeout_t timeout;
 	sctp_event_other_t other;
 	sctp_event_primitive_t primitive;
 } sctp_subtype_t;

 #define SCTP_SUBTYPE_CONSTRUCTOR(_name, _type, _elt) \
 static inline sctp_subtype_t	\
 SCTP_ST_## _name (_type _arg)		\
 { sctp_subtype_t _retval; _retval._elt = _arg; return _retval; }

 SCTP_SUBTYPE_CONSTRUCTOR(CHUNK,		enum sctp_cid,		chunk)
 SCTP_SUBTYPE_CONSTRUCTOR(TIMEOUT,	sctp_event_timeout_t,	timeout)
 SCTP_SUBTYPE_CONSTRUCTOR(OTHER,		sctp_event_other_t,	other)
 SCTP_SUBTYPE_CONSTRUCTOR(PRIMITIVE,	sctp_event_primitive_t,	primitive)


 #define sctp_chunk_is_data(a) (a->chunk_hdr->type == SCTP_CID_DATA)

 /* Calculate the actual data size in a data chunk */
 #define SCTP_DATA_SNDSIZE(c) ((int)((unsigned long)(c->chunk_end)\
 		       		- (unsigned long)(c->chunk_hdr)\
 				- sizeof(struct sctp_data_chunk)))

 /* Internal error codes */
 typedef enum {

 	SCTP_IERROR_NO_ERROR	        = 0,
 	SCTP_IERROR_BASE		= 1000,
 	SCTP_IERROR_NO_COOKIE,
 	SCTP_IERROR_BAD_SIG,
 	SCTP_IERROR_STALE_COOKIE,
 	SCTP_IERROR_NOMEM,
 	SCTP_IERROR_MALFORMED,
 	SCTP_IERROR_BAD_TAG,
 	SCTP_IERROR_BIG_GAP,
 	SCTP_IERROR_DUP_TSN,
 	SCTP_IERROR_HIGH_TSN,
 	SCTP_IERROR_IGNORE_TSN,
 	SCTP_IERROR_NO_DATA,
 	SCTP_IERROR_BAD_STREAM,
 	SCTP_IERROR_BAD_PORTS,
 	SCTP_IERROR_AUTH_BAD_HMAC,
 	SCTP_IERROR_AUTH_BAD_KEYID,
 	SCTP_IERROR_PROTO_VIOLATION,
 	SCTP_IERROR_ERROR,
 	SCTP_IERROR_ABORT,
 } sctp_ierror_t;


 /* SCTP state defines for internal state machine */
 typedef enum {

 	SCTP_STATE_CLOSED		= 0,
 	SCTP_STATE_COOKIE_WAIT		= 1,
 	SCTP_STATE_COOKIE_ECHOED	= 2,
 	SCTP_STATE_ESTABLISHED		= 3,
 	SCTP_STATE_SHUTDOWN_PENDING	= 4,
 	SCTP_STATE_SHUTDOWN_SENT	= 5,
 	SCTP_STATE_SHUTDOWN_RECEIVED	= 6,
 	SCTP_STATE_SHUTDOWN_ACK_SENT	= 7,

 } sctp_state_t;

 #define SCTP_STATE_MAX			SCTP_STATE_SHUTDOWN_ACK_SENT
 #define SCTP_STATE_NUM_STATES		(SCTP_STATE_MAX + 1)

 /* These are values for sk->state.
  * For a UDP-style SCTP socket, the states are defined as follows
  * - A socket in SCTP_SS_CLOSED state indicates that it is not willing to
  *   accept new associations, but it can initiate the creation of new ones.
  * - A socket in SCTP_SS_LISTENING state indicates that it is willing to
  *   accept new  associations and can initiate the creation of new ones.
  * - A socket in SCTP_SS_ESTABLISHED state indicates that it is a peeled off
  *   socket with one association.
  * For a TCP-style SCTP socket, the states are defined as follows
  * - A socket in SCTP_SS_CLOSED state indicates that it is not willing to
  *   accept new associations, but it can initiate the creation of new ones.
  * - A socket in SCTP_SS_LISTENING state indicates that it is willing to
  *   accept new associations, but cannot initiate the creation of new ones.
  * - A socket in SCTP_SS_ESTABLISHED state indicates that it has a single
  *   association.
  */
 enum sctp_sock_state {
 	SCTP_SS_CLOSED         = TCP_CLOSE,
 	SCTP_SS_LISTENING      = TCP_LISTEN,
 	SCTP_SS_ESTABLISHING   = TCP_SYN_SENT,
 	SCTP_SS_ESTABLISHED    = TCP_ESTABLISHED,
 	SCTP_SS_CLOSING        = TCP_CLOSE_WAIT,
 };

 /* These functions map various type to printable names.  */
 const char *sctp_cname(const sctp_subtype_t);	/* chunk types */
 const char *sctp_oname(const sctp_subtype_t);	/* other events */
 const char *sctp_tname(const sctp_subtype_t);	/* timeouts */
 const char *sctp_pname(const sctp_subtype_t);	/* primitives */

 /* This is a table of printable names of sctp_state_t's.  */
 extern const char *const sctp_state_tbl[];
 extern const char *const sctp_evttype_tbl[];
 extern const char *const sctp_status_tbl[];

 /* Maximum chunk length considering padding requirements. */
 enum { SCTP_MAX_CHUNK_LEN = ((1<<16) - sizeof(__u32)) };

 /* Encourage Cookie-Echo bundling by pre-fragmenting chunks a little
  * harder (until reaching ESTABLISHED state).
  */
 enum { SCTP_ARBITRARY_COOKIE_ECHO_LEN = 200 };

 /* Guess at how big to make the TSN mapping array.
  * We guarantee that we can handle at least this big a gap between the
  * cumulative ACK and the highest TSN.  In practice, we can often
  * handle up to twice this value.
  *
  * NEVER make this more than 32767 (2^15-1).  The Gap Ack Blocks in a
  * SACK (see  section 3.3.4) are only 16 bits, so 2*SCTP_TSN_MAP_SIZE
  * must be less than 65535 (2^16 - 1), or we will have overflow
  * problems creating SACK's.
  */
 #define SCTP_TSN_MAP_INITIAL BITS_PER_LONG
 #define SCTP_TSN_MAP_INCREMENT SCTP_TSN_MAP_INITIAL
 #define SCTP_TSN_MAP_SIZE 4096

 /* We will not record more than this many duplicate TSNs between two
  * SACKs.  The minimum PMTU is 576.  Remove all the headers and there
  * is enough room for 131 duplicate reports.  Round down to the
  * nearest power of 2.
  */
 enum { SCTP_MIN_PMTU = 576 };
 enum { SCTP_MAX_DUP_TSNS = 16 };
 enum { SCTP_MAX_GABS = 16 };

 /* Heartbeat interval - 30 secs */
 #define SCTP_DEFAULT_TIMEOUT_HEARTBEAT	(30*1000)

 /* Delayed sack timer - 200ms */
 #define SCTP_DEFAULT_TIMEOUT_SACK	(200)

 /* RTO.Initial              - 3  seconds
  * RTO.Min                  - 1  second
  * RTO.Max                  - 60 seconds
  * RTO.Alpha                - 1/8
  * RTO.Beta                 - 1/4
  */
 #define SCTP_RTO_INITIAL	(3 * 1000)
 #define SCTP_RTO_MIN		(1 * 1000)
 #define SCTP_RTO_MAX		(60 * 1000)

 #define SCTP_RTO_ALPHA          3   /* 1/8 when converted to right shifts. */
 #define SCTP_RTO_BETA           2   /* 1/4 when converted to right shifts. */

 /* Maximum number of new data packets that can be sent in a burst.  */
 #define SCTP_DEFAULT_MAX_BURST		4

 #define SCTP_CLOCK_GRANULARITY	1	/* 1 jiffy */

 #define SCTP_DEFAULT_COOKIE_LIFE	(60 * 1000) /* 60 seconds */

 #define SCTP_DEFAULT_MINWINDOW	1500	/* default minimum rwnd size */
 #define SCTP_DEFAULT_MAXWINDOW	65535	/* default rwnd size */
 #define SCTP_DEFAULT_RWND_SHIFT  4	/* by default, update on 1/16 of
 					 * rcvbuf, which is 1/8 of initial
 					 * window
 					 */
 #define SCTP_DEFAULT_MAXSEGMENT 1500	/* MTU size, this is the limit
                                          * to which we will raise the P-MTU.
 					 */
 #define SCTP_DEFAULT_MINSEGMENT 512	/* MTU size ... if no mtu disc */

 #define SCTP_SECRET_SIZE 32		/* Number of octets in a 256 bits. */

 #define SCTP_SIGNATURE_SIZE 20	        /* size of a SLA-1 signature */

 #define SCTP_COOKIE_MULTIPLE 32 /* Pad out our cookie to make our hash
 				 * functions simpler to write.
 				 */

 /* These return values describe the success or failure of a number of
  * routines which form the lower interface to SCTP_outqueue.
  */
 enum sctp_xmit {
 	SCTP_XMIT_OK,
 	SCTP_XMIT_PMTU_FULL,
 	SCTP_XMIT_RWND_FULL,
 	SCTP_XMIT_DELAY,
 };

 /* These are the commands for manipulating transports.  */
 enum sctp_transport_cmd {
 	SCTP_TRANSPORT_UP,
 	SCTP_TRANSPORT_DOWN,
 	SCTP_TRANSPORT_PF,
 };

 /* These are the address scopes defined mainly for IPv4 addresses
  * based on draft of SCTP IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>.
  * These scopes are hopefully generic enough to be used on scoping both
  * IPv4 and IPv6 addresses in SCTP.
  * At this point, the IPv6 scopes will be mapped to these internal scopes
  * as much as possible.
  */
 enum sctp_scope {
 	SCTP_SCOPE_GLOBAL,		/* IPv4 global addresses */
 	SCTP_SCOPE_PRIVATE,		/* IPv4 private addresses */
 	SCTP_SCOPE_LINK,		/* IPv4 link local address */
 	SCTP_SCOPE_LOOPBACK,		/* IPv4 loopback address */
 	SCTP_SCOPE_UNUSABLE,		/* IPv4 unusable addresses */
 };

 enum {
 	SCTP_SCOPE_POLICY_DISABLE,	/* Disable IPv4 address scoping */
 	SCTP_SCOPE_POLICY_ENABLE,	/* Enable IPv4 address scoping */
 	SCTP_SCOPE_POLICY_PRIVATE,	/* Follow draft but allow IPv4 private addresses */
 	SCTP_SCOPE_POLICY_LINK,		/* Follow draft but allow IPv4 link local addresses */
 };

 #define SCTP_SCOPE_POLICY_MAX	SCTP_SCOPE_POLICY_LINK

 /* Based on IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>,
  * SCTP IPv4 unusable addresses: 0.0.0.0/8, 224.0.0.0/4, 198.18.0.0/24,
  * 192.88.99.0/24.
  * Also, RFC 8.4, non-unicast addresses are not considered valid SCTP
  * addresses.
  */
 #define IS_IPV4_UNUSABLE_ADDRESS(a)	    \
 	((htonl(INADDR_BROADCAST) == a) ||  \
 	 ipv4_is_multicast(a) ||	    \
 	 ipv4_is_zeronet(a) ||		    \
 	 ipv4_is_test_198(a) ||		    \
 	 ipv4_is_anycast_6to4(a))

 /* Flags used for the bind address copy functions.  */
 #define SCTP_ADDR6_ALLOWED	0x00000001	/* IPv6 address is allowed by
 						   local sock family */
 #define SCTP_ADDR4_PEERSUPP	0x00000002	/* IPv4 address is supported by
 						   peer */
 #define SCTP_ADDR6_PEERSUPP	0x00000004	/* IPv6 address is supported by
 						   peer */

 /* Reasons to retransmit. */
 enum sctp_retransmit_reason {
 	SCTP_RTXR_T3_RTX,
 	SCTP_RTXR_FAST_RTX,
 	SCTP_RTXR_PMTUD,
 	SCTP_RTXR_T1_RTX,
 };

 /* Reasons to lower cwnd. */
 enum sctp_lower_cwnd {
 	SCTP_LOWER_CWND_T3_RTX,
 	SCTP_LOWER_CWND_FAST_RTX,
 	SCTP_LOWER_CWND_ECNE,
 	SCTP_LOWER_CWND_INACTIVE,
 };


 /* SCTP-AUTH Necessary constants */

 /* SCTP-AUTH, Section 3.3
  *
  *  The following Table 2 shows the currently defined values for HMAC
  *  identifiers.
  *
  *  +-----------------+--------------------------+
  *  | HMAC Identifier | Message Digest Algorithm |
  *  +-----------------+--------------------------+
  *  | 0               | Reserved                 |
  *  | 1               | SHA-1 defined in [8]     |
  *  | 2               | Reserved                 |
  *  | 3               | SHA-256 defined in [8]   |
  *  +-----------------+--------------------------+
  */
 enum {
 	SCTP_AUTH_HMAC_ID_RESERVED_0,
 	SCTP_AUTH_HMAC_ID_SHA1,
 	SCTP_AUTH_HMAC_ID_RESERVED_2,
 #if defined (CONFIG_CRYPTO_SHA256) || defined (CONFIG_CRYPTO_SHA256_MODULE)
 	SCTP_AUTH_HMAC_ID_SHA256,
 #endif
 	__SCTP_AUTH_HMAC_MAX
 };

 #define SCTP_AUTH_HMAC_ID_MAX	__SCTP_AUTH_HMAC_MAX - 1
 #define SCTP_AUTH_NUM_HMACS 	__SCTP_AUTH_HMAC_MAX
 #define SCTP_SHA1_SIG_SIZE 20
 #define SCTP_SHA256_SIG_SIZE 32

 /*  SCTP-AUTH, Section 3.2
  *     The chunk types for INIT, INIT-ACK, SHUTDOWN-COMPLETE and AUTH chunks
  *     MUST NOT be listed in the CHUNKS parameter
  */
 #define SCTP_NUM_NOAUTH_CHUNKS	4
 #define SCTP_AUTH_MAX_CHUNKS	(SCTP_NUM_CHUNK_TYPES - SCTP_NUM_NOAUTH_CHUNKS)

 /* SCTP-AUTH Section 6.1
  * The RANDOM parameter MUST contain a 32 byte random number.
  */
 #define SCTP_AUTH_RANDOM_LENGTH 32

 #endif /* __sctp_constants_h__ */
	/* SCTP kernel implementation
	* (C) Copyright IBM Corp. 2001, 2004
	* Copyright (c) 1999-2000 Cisco, Inc.
	* Copyright (c) 1999-2001 Motorola, Inc.
	* Copyright (c) 2001 Intel Corp.
	*
	* This file is part of the SCTP kernel implementation
	*
	* This SCTP implementation is free software;
	* you can redistribute it and/or modify it under the terms of
	* the GNU General Public License as published by
	* the Free Software Foundation; either version 2, or (at your option)
	* any later version.
	*
	* This SCTP implementation is distributed in the hope that it
	* will be useful, but WITHOUT ANY WARRANTY; without even the implied
	* ************************
	* warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
	* See the GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with GNU CC; see the file COPYING. If not, see
	* <http://www.gnu.org/licenses/>.
	*
	* Please send any bug reports or fixes you make to the
	* email address(es):
	* lksctp developers <linux-sctp@vger.kernel.org>
	*
	* Written or modified by:
	* La Monte H.P. Yarroll <piggy@acm.org>
	* Karl Knutson <karl@athena.chicago.il.us>
	* Randall Stewart <randall@stewart.chicago.il.us>
	* Ken Morneau <kmorneau@cisco.com>
	* Qiaobing Xie <qxie1@motorola.com>
	* Xingang Guo <xingang.guo@intel.com>
	* Sridhar Samudrala <samudrala@us.ibm.com>
	* Daisy Chang <daisyc@us.ibm.com>
	*/

	#ifndef __sctp_constants_h__
	#define __sctp_constants_h__

	#include <linux/sctp.h>
	#include <linux/ipv6.h> /* For ipv6hdr. */
	#include <net/tcp_states.h> /* For TCP states used in enum sctp_sock_state */

	/* Value used for stream negotiation. */
	enum { SCTP_MAX_STREAM = 0xffff };
	enum { SCTP_DEFAULT_OUTSTREAMS = 10 };
	enum { SCTP_DEFAULT_INSTREAMS = SCTP_MAX_STREAM };

	/* Since CIDs are sparse, we need all four of the following
	* symbols. CIDs are dense through SCTP_CID_BASE_MAX.
	*/
	#define SCTP_CID_BASE_MAX SCTP_CID_SHUTDOWN_COMPLETE

	#define SCTP_NUM_BASE_CHUNK_TYPES (SCTP_CID_BASE_MAX + 1)

	#define SCTP_NUM_ADDIP_CHUNK_TYPES 2

	#define SCTP_NUM_PRSCTP_CHUNK_TYPES 1

	#define SCTP_NUM_RECONF_CHUNK_TYPES 1

	#define SCTP_NUM_AUTH_CHUNK_TYPES 1

	#define SCTP_NUM_CHUNK_TYPES (SCTP_NUM_BASE_CHUNK_TYPES + \
	SCTP_NUM_ADDIP_CHUNK_TYPES +\
	SCTP_NUM_PRSCTP_CHUNK_TYPES +\
	SCTP_NUM_RECONF_CHUNK_TYPES +\
	SCTP_NUM_AUTH_CHUNK_TYPES)

	/* These are the different flavours of event. */
	typedef enum {

	SCTP_EVENT_T_CHUNK = 1,
	SCTP_EVENT_T_TIMEOUT,
	SCTP_EVENT_T_OTHER,
	SCTP_EVENT_T_PRIMITIVE

	} sctp_event_t;

	/* As a convenience for the state machine, we append SCTP_EVENT_* and
	* SCTP_ULP_* to the list of possible chunks.
	*/

	typedef enum {
	SCTP_EVENT_TIMEOUT_NONE = 0,
	SCTP_EVENT_TIMEOUT_T1_COOKIE,
	SCTP_EVENT_TIMEOUT_T1_INIT,
	SCTP_EVENT_TIMEOUT_T2_SHUTDOWN,
	SCTP_EVENT_TIMEOUT_T3_RTX,
	SCTP_EVENT_TIMEOUT_T4_RTO,
	SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD,
	SCTP_EVENT_TIMEOUT_HEARTBEAT,
	SCTP_EVENT_TIMEOUT_RECONF,
	SCTP_EVENT_TIMEOUT_SACK,
	SCTP_EVENT_TIMEOUT_AUTOCLOSE,
	} sctp_event_timeout_t;

	#define SCTP_EVENT_TIMEOUT_MAX SCTP_EVENT_TIMEOUT_AUTOCLOSE
	#define SCTP_NUM_TIMEOUT_TYPES (SCTP_EVENT_TIMEOUT_MAX + 1)

	typedef enum {
	SCTP_EVENT_NO_PENDING_TSN = 0,
	SCTP_EVENT_ICMP_PROTO_UNREACH,
	} sctp_event_other_t;

	#define SCTP_EVENT_OTHER_MAX SCTP_EVENT_ICMP_PROTO_UNREACH
	#define SCTP_NUM_OTHER_TYPES (SCTP_EVENT_OTHER_MAX + 1)

	/* These are primitive requests from the ULP. */
	typedef enum {
	SCTP_PRIMITIVE_ASSOCIATE = 0,
	SCTP_PRIMITIVE_SHUTDOWN,
	SCTP_PRIMITIVE_ABORT,
	SCTP_PRIMITIVE_SEND,
	SCTP_PRIMITIVE_REQUESTHEARTBEAT,
	SCTP_PRIMITIVE_ASCONF,
	SCTP_PRIMITIVE_RECONF,
	} sctp_event_primitive_t;

	#define SCTP_EVENT_PRIMITIVE_MAX SCTP_PRIMITIVE_RECONF
	#define SCTP_NUM_PRIMITIVE_TYPES (SCTP_EVENT_PRIMITIVE_MAX + 1)

	/* We define here a utility type for manipulating subtypes.
	* The subtype constructors all work like this:
	*
	* sctp_subtype_t foo = SCTP_ST_CHUNK(SCTP_CID_INIT);
	*/

	typedef union {
	enum sctp_cid chunk;
	sctp_event_timeout_t timeout;
	sctp_event_other_t other;
	sctp_event_primitive_t primitive;
	} sctp_subtype_t;

	#define SCTP_SUBTYPE_CONSTRUCTOR(_name, _type, _elt) \
	static inline sctp_subtype_t \
	SCTP_ST_## _name (_type _arg) \
	{ sctp_subtype_t _retval; _retval._elt = _arg; return _retval; }

	SCTP_SUBTYPE_CONSTRUCTOR(CHUNK, enum sctp_cid, chunk)
	SCTP_SUBTYPE_CONSTRUCTOR(TIMEOUT, sctp_event_timeout_t, timeout)
	SCTP_SUBTYPE_CONSTRUCTOR(OTHER, sctp_event_other_t, other)
	SCTP_SUBTYPE_CONSTRUCTOR(PRIMITIVE, sctp_event_primitive_t, primitive)


	#define sctp_chunk_is_data(a) (a->chunk_hdr->type == SCTP_CID_DATA)

	/* Calculate the actual data size in a data chunk */
	#define SCTP_DATA_SNDSIZE(c) ((int)((unsigned long)(c->chunk_end)\
	- (unsigned long)(c->chunk_hdr)\
	- sizeof(struct sctp_data_chunk)))

	/* Internal error codes */
	typedef enum {

	SCTP_IERROR_NO_ERROR = 0,
	SCTP_IERROR_BASE = 1000,
	SCTP_IERROR_NO_COOKIE,
	SCTP_IERROR_BAD_SIG,
	SCTP_IERROR_STALE_COOKIE,
	SCTP_IERROR_NOMEM,
	SCTP_IERROR_MALFORMED,
	SCTP_IERROR_BAD_TAG,
	SCTP_IERROR_BIG_GAP,
	SCTP_IERROR_DUP_TSN,
	SCTP_IERROR_HIGH_TSN,
	SCTP_IERROR_IGNORE_TSN,
	SCTP_IERROR_NO_DATA,
	SCTP_IERROR_BAD_STREAM,
	SCTP_IERROR_BAD_PORTS,
	SCTP_IERROR_AUTH_BAD_HMAC,
	SCTP_IERROR_AUTH_BAD_KEYID,
	SCTP_IERROR_PROTO_VIOLATION,
	SCTP_IERROR_ERROR,
	SCTP_IERROR_ABORT,
	} sctp_ierror_t;



	/* SCTP state defines for internal state machine */
	typedef enum {

	SCTP_STATE_CLOSED = 0,
	SCTP_STATE_COOKIE_WAIT = 1,
	SCTP_STATE_COOKIE_ECHOED = 2,
	SCTP_STATE_ESTABLISHED = 3,
	SCTP_STATE_SHUTDOWN_PENDING = 4,
	SCTP_STATE_SHUTDOWN_SENT = 5,
	SCTP_STATE_SHUTDOWN_RECEIVED = 6,
	SCTP_STATE_SHUTDOWN_ACK_SENT = 7,

	} sctp_state_t;

	#define SCTP_STATE_MAX SCTP_STATE_SHUTDOWN_ACK_SENT
	#define SCTP_STATE_NUM_STATES (SCTP_STATE_MAX + 1)

	/* These are values for sk->state.
	* For a UDP-style SCTP socket, the states are defined as follows
	* - A socket in SCTP_SS_CLOSED state indicates that it is not willing to
	* accept new associations, but it can initiate the creation of new ones.
	* - A socket in SCTP_SS_LISTENING state indicates that it is willing to
	* accept new associations and can initiate the creation of new ones.
	* - A socket in SCTP_SS_ESTABLISHED state indicates that it is a peeled off
	* socket with one association.
	* For a TCP-style SCTP socket, the states are defined as follows
	* - A socket in SCTP_SS_CLOSED state indicates that it is not willing to
	* accept new associations, but it can initiate the creation of new ones.
	* - A socket in SCTP_SS_LISTENING state indicates that it is willing to
	* accept new associations, but cannot initiate the creation of new ones.
	* - A socket in SCTP_SS_ESTABLISHED state indicates that it has a single
	* association.
	*/
	enum sctp_sock_state {
	SCTP_SS_CLOSED = TCP_CLOSE,
	SCTP_SS_LISTENING = TCP_LISTEN,
	SCTP_SS_ESTABLISHING = TCP_SYN_SENT,
	SCTP_SS_ESTABLISHED = TCP_ESTABLISHED,
	SCTP_SS_CLOSING = TCP_CLOSE_WAIT,
	};

	/* These functions map various type to printable names. */
	const char sctp_cname(const sctp_subtype_t); / chunk types */
	const char sctp_oname(const sctp_subtype_t); / other events */
	const char sctp_tname(const sctp_subtype_t); / timeouts */
	const char sctp_pname(const sctp_subtype_t); / primitives */

	/* This is a table of printable names of sctp_state_t's. */
	extern const char *const sctp_state_tbl[];
	extern const char *const sctp_evttype_tbl[];
	extern const char *const sctp_status_tbl[];

	/* Maximum chunk length considering padding requirements. */
	enum { SCTP_MAX_CHUNK_LEN = ((1<<16) - sizeof(__u32)) };

	/* Encourage Cookie-Echo bundling by pre-fragmenting chunks a little
	* harder (until reaching ESTABLISHED state).
	*/
	enum { SCTP_ARBITRARY_COOKIE_ECHO_LEN = 200 };

	/* Guess at how big to make the TSN mapping array.
	* We guarantee that we can handle at least this big a gap between the
	* cumulative ACK and the highest TSN. In practice, we can often
	* handle up to twice this value.
	*
	* NEVER make this more than 32767 (2^15-1). The Gap Ack Blocks in a
	* SACK (see section 3.3.4) are only 16 bits, so 2*SCTP_TSN_MAP_SIZE
	* must be less than 65535 (2^16 - 1), or we will have overflow
	* problems creating SACK's.
	*/
	#define SCTP_TSN_MAP_INITIAL BITS_PER_LONG
	#define SCTP_TSN_MAP_INCREMENT SCTP_TSN_MAP_INITIAL
	#define SCTP_TSN_MAP_SIZE 4096

	/* We will not record more than this many duplicate TSNs between two
	* SACKs. The minimum PMTU is 576. Remove all the headers and there
	* is enough room for 131 duplicate reports. Round down to the
	* nearest power of 2.
	*/
	enum { SCTP_MIN_PMTU = 576 };
	enum { SCTP_MAX_DUP_TSNS = 16 };
	enum { SCTP_MAX_GABS = 16 };

	/* Heartbeat interval - 30 secs */
	#define SCTP_DEFAULT_TIMEOUT_HEARTBEAT (30*1000)

	/* Delayed sack timer - 200ms */
	#define SCTP_DEFAULT_TIMEOUT_SACK (200)

	/* RTO.Initial - 3 seconds
	* RTO.Min - 1 second
	* RTO.Max - 60 seconds
	* RTO.Alpha - 1/8
	* RTO.Beta - 1/4
	*/
	#define SCTP_RTO_INITIAL (3 * 1000)
	#define SCTP_RTO_MIN (1 * 1000)
	#define SCTP_RTO_MAX (60 * 1000)

	#define SCTP_RTO_ALPHA 3 /* 1/8 when converted to right shifts. */
	#define SCTP_RTO_BETA 2 /* 1/4 when converted to right shifts. */

	/* Maximum number of new data packets that can be sent in a burst. */
	#define SCTP_DEFAULT_MAX_BURST 4

	#define SCTP_CLOCK_GRANULARITY 1 /* 1 jiffy */

	#define SCTP_DEFAULT_COOKIE_LIFE (60 * 1000) /* 60 seconds */

	#define SCTP_DEFAULT_MINWINDOW 1500 /* default minimum rwnd size */
	#define SCTP_DEFAULT_MAXWINDOW 65535 /* default rwnd size */
	#define SCTP_DEFAULT_RWND_SHIFT 4 /* by default, update on 1/16 of
	* rcvbuf, which is 1/8 of initial
	* window
	*/
	#define SCTP_DEFAULT_MAXSEGMENT 1500 /* MTU size, this is the limit
	* to which we will raise the P-MTU.
	*/
	#define SCTP_DEFAULT_MINSEGMENT 512 /* MTU size ... if no mtu disc */

	#define SCTP_SECRET_SIZE 32 /* Number of octets in a 256 bits. */

	#define SCTP_SIGNATURE_SIZE 20 /* size of a SLA-1 signature */

	#define SCTP_COOKIE_MULTIPLE 32 /* Pad out our cookie to make our hash
	* functions simpler to write.
	*/

	/* These return values describe the success or failure of a number of
	* routines which form the lower interface to SCTP_outqueue.
	*/
	enum sctp_xmit {
	SCTP_XMIT_OK,
	SCTP_XMIT_PMTU_FULL,
	SCTP_XMIT_RWND_FULL,
	SCTP_XMIT_DELAY,
	};

	/* These are the commands for manipulating transports. */
	enum sctp_transport_cmd {
	SCTP_TRANSPORT_UP,
	SCTP_TRANSPORT_DOWN,
	SCTP_TRANSPORT_PF,
	};

	/* These are the address scopes defined mainly for IPv4 addresses
	* based on draft of SCTP IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>.
	* These scopes are hopefully generic enough to be used on scoping both
	* IPv4 and IPv6 addresses in SCTP.
	* At this point, the IPv6 scopes will be mapped to these internal scopes
	* as much as possible.
	*/
	enum sctp_scope {
	SCTP_SCOPE_GLOBAL, /* IPv4 global addresses */
	SCTP_SCOPE_PRIVATE, /* IPv4 private addresses */
	SCTP_SCOPE_LINK, /* IPv4 link local address */
	SCTP_SCOPE_LOOPBACK, /* IPv4 loopback address */
	SCTP_SCOPE_UNUSABLE, /* IPv4 unusable addresses */
	};

	enum {
	SCTP_SCOPE_POLICY_DISABLE, /* Disable IPv4 address scoping */
	SCTP_SCOPE_POLICY_ENABLE, /* Enable IPv4 address scoping */
	SCTP_SCOPE_POLICY_PRIVATE, /* Follow draft but allow IPv4 private addresses */
	SCTP_SCOPE_POLICY_LINK, /* Follow draft but allow IPv4 link local addresses */
	};

	#define SCTP_SCOPE_POLICY_MAX SCTP_SCOPE_POLICY_LINK

	/* Based on IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>,
	* SCTP IPv4 unusable addresses: 0.0.0.0/8, 224.0.0.0/4, 198.18.0.0/24,
	* 192.88.99.0/24.
	* Also, RFC 8.4, non-unicast addresses are not considered valid SCTP
	* addresses.
	*/
	#define IS_IPV4_UNUSABLE_ADDRESS(a) \
	((htonl(INADDR_BROADCAST) == a) \|\| \
	ipv4_is_multicast(a) \|\| \
	ipv4_is_zeronet(a) \|\| \
	ipv4_is_test_198(a) \|\| \
	ipv4_is_anycast_6to4(a))

	/* Flags used for the bind address copy functions. */
	#define SCTP_ADDR6_ALLOWED 0x00000001 /* IPv6 address is allowed by
	local sock family */
	#define SCTP_ADDR4_PEERSUPP 0x00000002 /* IPv4 address is supported by
	peer */
	#define SCTP_ADDR6_PEERSUPP 0x00000004 /* IPv6 address is supported by
	peer */

	/* Reasons to retransmit. */
	enum sctp_retransmit_reason {
	SCTP_RTXR_T3_RTX,
	SCTP_RTXR_FAST_RTX,
	SCTP_RTXR_PMTUD,
	SCTP_RTXR_T1_RTX,
	};

	/* Reasons to lower cwnd. */
	enum sctp_lower_cwnd {
	SCTP_LOWER_CWND_T3_RTX,
	SCTP_LOWER_CWND_FAST_RTX,
	SCTP_LOWER_CWND_ECNE,
	SCTP_LOWER_CWND_INACTIVE,
	};


	/* SCTP-AUTH Necessary constants */

	/* SCTP-AUTH, Section 3.3
	*
	* The following Table 2 shows the currently defined values for HMAC
	* identifiers.
	*
	* +-----------------+--------------------------+
	* \| HMAC Identifier \| Message Digest Algorithm \|
	* +-----------------+--------------------------+
	* \| 0 \| Reserved \|
	* \| 1 \| SHA-1 defined in [8] \|
	* \| 2 \| Reserved \|
	* \| 3 \| SHA-256 defined in [8] \|
	* +-----------------+--------------------------+
	*/
	enum {
	SCTP_AUTH_HMAC_ID_RESERVED_0,
	SCTP_AUTH_HMAC_ID_SHA1,
	SCTP_AUTH_HMAC_ID_RESERVED_2,
	#if defined (CONFIG_CRYPTO_SHA256) \|\| defined (CONFIG_CRYPTO_SHA256_MODULE)
	SCTP_AUTH_HMAC_ID_SHA256,
	#endif
	__SCTP_AUTH_HMAC_MAX
	};

	#define SCTP_AUTH_HMAC_ID_MAX __SCTP_AUTH_HMAC_MAX - 1
	#define SCTP_AUTH_NUM_HMACS __SCTP_AUTH_HMAC_MAX
	#define SCTP_SHA1_SIG_SIZE 20
	#define SCTP_SHA256_SIG_SIZE 32

	/* SCTP-AUTH, Section 3.2
	* The chunk types for INIT, INIT-ACK, SHUTDOWN-COMPLETE and AUTH chunks
	* MUST NOT be listed in the CHUNKS parameter
	*/
	#define SCTP_NUM_NOAUTH_CHUNKS 4
	#define SCTP_AUTH_MAX_CHUNKS (SCTP_NUM_CHUNK_TYPES - SCTP_NUM_NOAUTH_CHUNKS)

	/* SCTP-AUTH Section 6.1
	* The RANDOM parameter MUST contain a 32 byte random number.
	*/
	#define SCTP_AUTH_RANDOM_LENGTH 32

	#endif /* __sctp_constants_h__ */