sctp.h

SCTP 协议实现源代码

 *   message this notification will be used to indicate
 *   various events.
 */
struct sctp_pdapi_event {
	__u16 pdapi_type;
	__u16 pdapi_flags;
	__u32 pdapi_length;
	__u32 pdapi_indication;
	sctp_assoc_t pdapi_assoc_id;
};

enum { SCTP_PARTIAL_DELIVERY_ABORTED=0, };

/*
 * Described in Section 7.3
 *   Ancillary Data and Notification Interest Options
 */
struct sctp_event_subscribe {
	__u8 sctp_data_io_event;
	__u8 sctp_association_event;
	__u8 sctp_address_event;
	__u8 sctp_send_failure_event;
	__u8 sctp_peer_error_event;
	__u8 sctp_shutdown_event;
	__u8 sctp_partial_delivery_event;
	__u8 sctp_adaptation_layer_event;
};

/*
 * 5.3.1 SCTP Notification Structure
 *
 *   The notification structure is defined as the union of all
 *   notification types.
 *
 */
union sctp_notification {
	struct {
		__u16 sn_type;             /* Notification type. */
		__u16 sn_flags;
		__u32 sn_length;
	} sn_header;
	struct sctp_assoc_change sn_assoc_change;
	struct sctp_paddr_change sn_paddr_change;
	struct sctp_remote_error sn_remote_error;
	struct sctp_send_failed sn_send_failed;
	struct sctp_shutdown_event sn_shutdown_event;
	struct sctp_adaptation_event sn_adaptation_event;
	struct sctp_pdapi_event sn_pdapi_event;
};

/* Section 5.3.1
 * All standard values for sn_type flags are greater than 2^15.
 * Values from 2^15 and down are reserved.
 */

enum sctp_sn_type {
	SCTP_SN_TYPE_BASE     = (1<<15),
	SCTP_ASSOC_CHANGE,
	SCTP_PEER_ADDR_CHANGE,
	SCTP_SEND_FAILED,
	SCTP_REMOTE_ERROR,
	SCTP_SHUTDOWN_EVENT,
	SCTP_PARTIAL_DELIVERY_EVENT,
	SCTP_ADAPTATION_INDICATION,
};

/* Notification error codes used to fill up the error fields in some
 * notifications.
 * SCTP_PEER_ADDRESS_CHAGE 	: spc_error
 * SCTP_ASSOC_CHANGE		: sac_error
 * These names should be potentially included in the draft 04 of the SCTP
 * sockets API specification.
 */
typedef enum sctp_sn_error {
	SCTP_FAILED_THRESHOLD,
	SCTP_RECEIVED_SACK,
	SCTP_HEARTBEAT_SUCCESS,
	SCTP_RESPONSE_TO_USER_REQ,
	SCTP_INTERNAL_ERROR,
	SCTP_SHUTDOWN_GUARD_EXPIRES,
	SCTP_PEER_FAULTY,
} sctp_sn_error_t;

/*
 * 7.1.1 Retransmission Timeout Parameters (SCTP_RTOINFO)
 *
 *   The protocol parameters used to initialize and bound retransmission
 *   timeout (RTO) are tunable.  See [SCTP] for more information on how
 *   these parameters are used in RTO calculation. 
 */
struct sctp_rtoinfo {
	sctp_assoc_t	srto_assoc_id;
	__u32		srto_initial;
	__u32		srto_max;
	__u32		srto_min;
};

/*
 * 7.1.2 Association Parameters (SCTP_ASSOCINFO)
 *
 *   This option is used to both examine and set various association and
 *   endpoint parameters.
 */
struct sctp_assocparams {
	sctp_assoc_t	sasoc_assoc_id;
	__u16		sasoc_asocmaxrxt;
	__u16		sasoc_number_peer_destinations;
	__u32		sasoc_peer_rwnd;
	__u32		sasoc_local_rwnd;
	__u32		sasoc_cookie_life;
};

/*
 * 7.1.9 Set Peer Primary Address (SCTP_SET_PEER_PRIMARY_ADDR)
 *
 *  Requests that the peer mark the enclosed address as the association
 *  primary. The enclosed address must be one of the association's
 *  locally bound addresses. The following structure is used to make a
 *   set primary request:
 */
struct sctp_setpeerprim {
	sctp_assoc_t            sspp_assoc_id;
	struct sockaddr_storage sspp_addr;
} __attribute__((packed, aligned(4)));

/*
 * 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
 *
 *  Requests that the local SCTP stack use the enclosed peer address as
 *  the association primary. The enclosed address must be one of the
 *  association peer's addresses. The following structure is used to
 *  make a set peer primary request:
 */
struct sctp_setprim {
	sctp_assoc_t            ssp_assoc_id;
	struct sockaddr_storage ssp_addr;
} __attribute__((packed, aligned(4)));

/* For backward compatibility use, define the old name too */
#define sctp_prim sctp_setprim

/*
 * 7.1.11 Set Adaptation Layer Indicator (SCTP_ADAPTATION_LAYER)
 *
 * Requests that the local endpoint set the specified Adaptation Layer
 * Indication parameter for all future INIT and INIT-ACK exchanges.
 */
struct sctp_setadaptation {
	__u32	ssb_adaptation_ind;
};

/*
 * 7.1.13 Peer Address Parameters  (SCTP_PEER_ADDR_PARAMS)
 *
 *   Applications can enable or disable heartbeats for any peer address
 *   of an association, modify an address's heartbeat interval, force a
 *   heartbeat to be sent immediately, and adjust the address's maximum
 *   number of retransmissions sent before an address is considered
 *   unreachable. The following structure is used to access and modify an
 *   address's parameters:
 */
enum  sctp_spp_flags {
	SPP_HB_ENABLE = 1<<0,		/*Enable heartbeats*/
	SPP_HB_DISABLE = 1<<1,		/*Disable heartbeats*/
	SPP_HB = SPP_HB_ENABLE | SPP_HB_DISABLE,
	SPP_HB_DEMAND = 1<<2,		/*Send heartbeat immediately*/
	SPP_PMTUD_ENABLE = 1<<3,	/*Enable PMTU discovery*/
	SPP_PMTUD_DISABLE = 1<<4,	/*Disable PMTU discovery*/
	SPP_PMTUD = SPP_PMTUD_ENABLE | SPP_PMTUD_DISABLE,
	SPP_SACKDELAY_ENABLE = 1<<5,	/*Enable SACK*/
	SPP_SACKDELAY_DISABLE = 1<<6,	/*Disable SACK*/
	SPP_SACKDELAY = SPP_SACKDELAY_ENABLE | SPP_SACKDELAY_DISABLE,
	SPP_HB_TIME_IS_ZERO = 1<<7,	/* Set HB delay to 0 */
};

struct sctp_paddrparams {
	sctp_assoc_t		spp_assoc_id;
	struct sockaddr_storage	spp_address;
	__u32			spp_hbinterval;
	__u16			spp_pathmaxrxt;
	__u32			spp_pathmtu;
	__u32			spp_sackdelay;
	__u32			spp_flags;
} __attribute__((packed, aligned(4)));

/* 7.1.24. Delayed Ack Timer (SCTP_DELAYED_ACK_TIME)
 *
 *   This options will get or set the delayed ack timer.  The time is set
 *   in milliseconds.  If the assoc_id is 0, then this sets or gets the
 *   endpoints default delayed ack timer value.  If the assoc_id field is
 *   non-zero, then the set or get effects the specified association.
 */
struct sctp_assoc_value {
    sctp_assoc_t            assoc_id;
    uint32_t                assoc_value;
};

/*
 * 7.2.2 Peer Address Information
 *
 *   Applications can retrieve information about a specific peer address
 *   of an association, including its reachability state, congestion
 *   window, and retransmission timer values.  This information is
 *   read-only. The following structure is used to access this
 *   information:
 */
struct sctp_paddrinfo {
	sctp_assoc_t		spinfo_assoc_id;
	struct sockaddr_storage	spinfo_address;
	__s32			spinfo_state;
	__u32			spinfo_cwnd;
	__u32			spinfo_srtt;
	__u32			spinfo_rto;
	__u32			spinfo_mtu;
} __attribute__((packed, aligned(4)));

/* Peer addresses's state. */
enum sctp_spinfo_state {
	SCTP_INACTIVE,
	SCTP_ACTIVE,
	SCTP_UNCONFIRMED
};

/*
 * 7.2.1 Association Status (SCTP_STATUS)
 *
 *   Applications can retrieve current status information about an
 *   association, including association state, peer receiver window size,
 *   number of unacked data chunks, and number of data chunks pending
 *   receipt.  This information is read-only.  The following structure is
 *   used to access this information:
 */
struct sctp_status {
	sctp_assoc_t		sstat_assoc_id;
	__s32			sstat_state;
	__u32			sstat_rwnd;
	__u16			sstat_unackdata;
	__u16			sstat_penddata;
	__u16			sstat_instrms;
	__u16			sstat_outstrms;
	__u32			sstat_fragmentation_point;
	struct sctp_paddrinfo	sstat_primary;
};

/* Association states.  */
enum sctp_sstat_state {
	SCTP_EMPTY                = 0,
	SCTP_CLOSED               = 1,
	SCTP_COOKIE_WAIT          = 2,
	SCTP_COOKIE_ECHOED        = 3,
	SCTP_ESTABLISHED          = 4,
	SCTP_SHUTDOWN_PENDING     = 5,
	SCTP_SHUTDOWN_SENT        = 6,
	SCTP_SHUTDOWN_RECEIVED    = 7,
	SCTP_SHUTDOWN_ACK_SENT    = 8,
};

/*
 * 8.3, 8.5 get all peer/local addresses in an association.
 * This parameter struct is used by SCTP_GET_PEER_ADDRS and
 * SCTP_GET_LOCAL_ADDRS socket options used internally to implement
 * sctp_getpaddrs() and sctp_getladdrs() API. 
 */
struct sctp_getaddrs_old {
	sctp_assoc_t            assoc_id;
	int			addr_num;
	struct sockaddr		*addrs;
};
struct sctp_getaddrs {
	sctp_assoc_t		assoc_id; /*input*/
	__u32			addr_num; /*output*/
	__u8			addrs[0]; /*output, variable size*/
};

/* These are bit fields for msghdr->msg_flags.  See section 5.1.  */
/* On user space Linux, these live in <bits/socket.h> as an enum.  */
enum sctp_msg_flags {
	MSG_NOTIFICATION = 0x8000,
#define MSG_NOTIFICATION MSG_NOTIFICATION
};

/*
 * 8.1 sctp_bindx()
 *
 * The flags parameter is formed from the bitwise OR of zero or more of the
 * following currently defined flags:
 */
#define SCTP_BINDX_ADD_ADDR 0x01
#define SCTP_BINDX_REM_ADDR 0x02

/* This is the structure that is passed as an argument(optval) to
 * getsockopt(SCTP_SOCKOPT_PEELOFF).
 */
typedef struct {
	sctp_assoc_t associd;
	int sd;
} sctp_peeloff_arg_t;


int sctp_bindx(int sd, struct sockaddr *addrs, int addrcnt, int flags);

int sctp_connectx(int sd, struct sockaddr *addrs, int addrcnt);

int sctp_peeloff(int sd, sctp_assoc_t assoc_id);

/* Prototype for the library function sctp_opt_info defined in
 * API 7. Socket Options.
 */
int sctp_opt_info(int sd, sctp_assoc_t id, int opt, void *arg, socklen_t *size);

/* Get all peer address on a socket.  This is a new SCTP API
 * described in the section 8.3 of the Sockets API Extensions for SCTP.
 * This is implemented using the getsockopt() interface.
 */
int sctp_getpaddrs(int sd, sctp_assoc_t id, struct sockaddr **addrs);

/* Frees all resources allocated by sctp_getpaddrs().  This is a new SCTP API
 * described in the section 8.4 of the Sockets API Extensions for SCTP.
 */
int sctp_freepaddrs(struct sockaddr *addrs);

/* Get all locally bound address on a socket.  This is a new SCTP API
 * described in the section 8.5 of the Sockets API Extensions for SCTP.
 * This is implemented using the getsockopt() interface.
 */
int sctp_getladdrs(int sd, sctp_assoc_t id, struct sockaddr **addrs);

/* Frees all resources allocated by sctp_getladdrs().  This is a new SCTP API
 * described in the section 8.6 of the Sockets API Extensions for SCTP.
 */
int sctp_freeladdrs(struct sockaddr *addrs);

/* This library function assists the user with the advanced features
 * of SCTP.  This is a new SCTP API described in the section 8.7 of the
 * Sockets API Extensions for SCTP. This is implemented using the
 * sendmsg() interface.
 */
int sctp_sendmsg(int s, const void *msg, size_t len, struct sockaddr *to,
		 socklen_t tolen, uint32_t ppid, uint32_t flags,
		 uint16_t stream_no, uint32_t timetolive, uint32_t context);

/* This library function assist the user with sending a message without
 * dealing directly with the CMSG header.
 */
int sctp_send(int s, const void *msg, size_t len,
              const struct sctp_sndrcvinfo *sinfo, int flags);

/* This library function assists the user with the advanced features
 * of SCTP.  This is a new SCTP API described in the section 8.8 of the
 * Sockets API Extensions for SCTP. This is implemented using the
 * recvmsg() interface.
 */
int sctp_recvmsg(int s, void *msg, size_t len, struct sockaddr *from,
		 socklen_t *fromlen, struct sctp_sndrcvinfo *sinfo,
		 int *msg_flags);

/* Return the address length for an address family. */
int sctp_getaddrlen(sa_family_t family);

__END_DECLS

#endif /* __linux_sctp_h__ */