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Diffstat (limited to 'include/net/sctp/structs.h')
| -rw-r--r-- | include/net/sctp/structs.h | 1752 |
1 files changed, 1752 insertions, 0 deletions
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h new file mode 100644 index 000000000000..7e64cf6bda1e --- /dev/null +++ b/include/net/sctp/structs.h @@ -0,0 +1,1752 @@ +/* SCTP kernel reference 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 reference Implementation + * + * The SCTP reference 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. + * + * The SCTP reference 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, write to + * the Free Software Foundation, 59 Temple Place - Suite 330, + * Boston, MA 02111-1307, USA. + * + * Please send any bug reports or fixes you make to the + * email addresses: + * lksctp developers <lksctp-developers@lists.sourceforge.net> + * + * Or submit a bug report through the following website: + * http://www.sf.net/projects/lksctp + * + * Written or modified by: + * Randall Stewart <randall@sctp.chicago.il.us> + * Ken Morneau <kmorneau@cisco.com> + * Qiaobing Xie <qxie1@email.mot.com> + * La Monte H.P. Yarroll <piggy@acm.org> + * Karl Knutson <karl@athena.chicago.il.us> + * Jon Grimm <jgrimm@us.ibm.com> + * Xingang Guo <xingang.guo@intel.com> + * Hui Huang <hui.huang@nokia.com> + * Sridhar Samudrala <sri@us.ibm.com> + * Daisy Chang <daisyc@us.ibm.com> + * Dajiang Zhang <dajiang.zhang@nokia.com> + * Ardelle Fan <ardelle.fan@intel.com> + * Ryan Layer <rmlayer@us.ibm.com> + * Anup Pemmaiah <pemmaiah@cc.usu.edu> + * Kevin Gao <kevin.gao@intel.com> + * + * Any bugs reported given to us we will try to fix... any fixes shared will + * be incorporated into the next SCTP release. + */ + +#ifndef __sctp_structs_h__ +#define __sctp_structs_h__ + +#include <linux/time.h> /* We get struct timespec. */ +#include <linux/socket.h> /* linux/in.h needs this!! */ +#include <linux/in.h> /* We get struct sockaddr_in. */ +#include <linux/in6.h> /* We get struct in6_addr */ +#include <linux/ipv6.h> +#include <asm/param.h> /* We get MAXHOSTNAMELEN. */ +#include <asm/atomic.h> /* This gets us atomic counters. */ +#include <linux/skbuff.h> /* We need sk_buff_head. */ +#include <linux/workqueue.h> /* We need tq_struct. */ +#include <linux/sctp.h> /* We need sctp* header structs. */ + +/* A convenience structure for handling sockaddr structures. + * We should wean ourselves off this. + */ +union sctp_addr { + struct sockaddr_in v4; + struct sockaddr_in6 v6; + struct sockaddr sa; +}; + +/* Forward declarations for data structures. */ +struct sctp_globals; +struct sctp_endpoint; +struct sctp_association; +struct sctp_transport; +struct sctp_packet; +struct sctp_chunk; +struct sctp_inq; +struct sctp_outq; +struct sctp_bind_addr; +struct sctp_ulpq; +struct sctp_ep_common; +struct sctp_ssnmap; + + +#include <net/sctp/tsnmap.h> +#include <net/sctp/ulpevent.h> +#include <net/sctp/ulpqueue.h> + +/* Structures useful for managing bind/connect. */ + +struct sctp_bind_bucket { + unsigned short port; + unsigned short fastreuse; + struct sctp_bind_bucket *next; + struct sctp_bind_bucket **pprev; + struct hlist_head owner; +}; + +struct sctp_bind_hashbucket { + spinlock_t lock; + struct sctp_bind_bucket *chain; +}; + +/* Used for hashing all associations. */ +struct sctp_hashbucket { + rwlock_t lock; + struct sctp_ep_common *chain; +} __attribute__((__aligned__(8))); + + +/* The SCTP globals structure. */ +extern struct sctp_globals { + /* RFC2960 Section 14. Suggested SCTP Protocol Parameter Values + * + * The following protocol parameters are RECOMMENDED: + * + * RTO.Initial - 3 seconds + * RTO.Min - 1 second + * RTO.Max - 60 seconds + * RTO.Alpha - 1/8 (3 when converted to right shifts.) + * RTO.Beta - 1/4 (2 when converted to right shifts.) + */ + __u32 rto_initial; + __u32 rto_min; + __u32 rto_max; + + /* Note: rto_alpha and rto_beta are really defined as inverse + * powers of two to facilitate integer operations. + */ + int rto_alpha; + int rto_beta; + + /* Max.Burst - 4 */ + int max_burst; + + /* Valid.Cookie.Life - 60 seconds */ + int valid_cookie_life; + + /* Whether Cookie Preservative is enabled(1) or not(0) */ + int cookie_preserve_enable; + + /* Association.Max.Retrans - 10 attempts + * Path.Max.Retrans - 5 attempts (per destination address) + * Max.Init.Retransmits - 8 attempts + */ + int max_retrans_association; + int max_retrans_path; + int max_retrans_init; + + /* HB.interval - 30 seconds */ + int hb_interval; + + /* The following variables are implementation specific. */ + + /* Default initialization values to be applied to new associations. */ + __u16 max_instreams; + __u16 max_outstreams; + + /* This is a list of groups of functions for each address + * family that we support. + */ + struct list_head address_families; + + /* This is the hash of all endpoints. */ + int ep_hashsize; + struct sctp_hashbucket *ep_hashtable; + + /* This is the hash of all associations. */ + int assoc_hashsize; + struct sctp_hashbucket *assoc_hashtable; + + /* This is the sctp port control hash. */ + int port_hashsize; + int port_rover; + spinlock_t port_alloc_lock; /* Protects port_rover. */ + struct sctp_bind_hashbucket *port_hashtable; + + /* This is the global local address list. + * We actively maintain this complete list of interfaces on + * the system by catching routing events. + * + * It is a list of sctp_sockaddr_entry. + */ + struct list_head local_addr_list; + spinlock_t local_addr_lock; + + /* Flag to indicate if addip is enabled. */ + int addip_enable; + + /* Flag to indicate if PR-SCTP is enabled. */ + int prsctp_enable; +} sctp_globals; + +#define sctp_rto_initial (sctp_globals.rto_initial) +#define sctp_rto_min (sctp_globals.rto_min) +#define sctp_rto_max (sctp_globals.rto_max) +#define sctp_rto_alpha (sctp_globals.rto_alpha) +#define sctp_rto_beta (sctp_globals.rto_beta) +#define sctp_max_burst (sctp_globals.max_burst) +#define sctp_valid_cookie_life (sctp_globals.valid_cookie_life) +#define sctp_cookie_preserve_enable (sctp_globals.cookie_preserve_enable) +#define sctp_max_retrans_association (sctp_globals.max_retrans_association) +#define sctp_max_retrans_path (sctp_globals.max_retrans_path) +#define sctp_max_retrans_init (sctp_globals.max_retrans_init) +#define sctp_hb_interval (sctp_globals.hb_interval) +#define sctp_max_instreams (sctp_globals.max_instreams) +#define sctp_max_outstreams (sctp_globals.max_outstreams) +#define sctp_address_families (sctp_globals.address_families) +#define sctp_ep_hashsize (sctp_globals.ep_hashsize) +#define sctp_ep_hashtable (sctp_globals.ep_hashtable) +#define sctp_assoc_hashsize (sctp_globals.assoc_hashsize) +#define sctp_assoc_hashtable (sctp_globals.assoc_hashtable) +#define sctp_port_hashsize (sctp_globals.port_hashsize) +#define sctp_port_rover (sctp_globals.port_rover) +#define sctp_port_alloc_lock (sctp_globals.port_alloc_lock) +#define sctp_port_hashtable (sctp_globals.port_hashtable) +#define sctp_local_addr_list (sctp_globals.local_addr_list) +#define sctp_local_addr_lock (sctp_globals.local_addr_lock) +#define sctp_addip_enable (sctp_globals.addip_enable) +#define sctp_prsctp_enable (sctp_globals.prsctp_enable) + +/* SCTP Socket type: UDP or TCP style. */ +typedef enum { + SCTP_SOCKET_UDP = 0, + SCTP_SOCKET_UDP_HIGH_BANDWIDTH, + SCTP_SOCKET_TCP +} sctp_socket_type_t; + +/* Per socket SCTP information. */ +struct sctp_sock { + /* inet_sock has to be the first member of sctp_sock */ + struct inet_sock inet; + /* What kind of a socket is this? */ + sctp_socket_type_t type; + + /* PF_ family specific functions. */ + struct sctp_pf *pf; + + /* Access to HMAC transform. */ + struct crypto_tfm *hmac; + + /* What is our base endpointer? */ + struct sctp_endpoint *ep; + + struct sctp_bind_bucket *bind_hash; + /* Various Socket Options. */ + __u16 default_stream; + __u32 default_ppid; + __u16 default_flags; + __u32 default_context; + __u32 default_timetolive; + + struct sctp_initmsg initmsg; + struct sctp_rtoinfo rtoinfo; + struct sctp_paddrparams paddrparam; + struct sctp_event_subscribe subscribe; + struct sctp_assocparams assocparams; + int user_frag; + __u32 autoclose; + __u8 nodelay; + __u8 disable_fragments; + __u8 pd_mode; + __u8 v4mapped; + __u32 adaption_ind; + + /* Receive to here while partial delivery is in effect. */ + struct sk_buff_head pd_lobby; +}; + +static inline struct sctp_sock *sctp_sk(const struct sock *sk) +{ + return (struct sctp_sock *)sk; +} + +static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp) +{ + return (struct sock *)sp; +} + +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) +struct sctp6_sock { + struct sctp_sock sctp; + struct ipv6_pinfo inet6; +}; +#endif /* CONFIG_IPV6 */ + + +/* This is our APPLICATION-SPECIFIC state cookie. + * THIS IS NOT DICTATED BY THE SPECIFICATION. + */ +/* These are the parts of an association which we send in the cookie. + * Most of these are straight out of: + * RFC2960 12.2 Parameters necessary per association (i.e. the TCB) + * + */ + +struct sctp_cookie { + + /* My : Tag expected in every inbound packet and sent + * Verification: in the INIT or INIT ACK chunk. + * Tag : + */ + __u32 my_vtag; + + /* Peer's : Tag expected in every outbound packet except + * Verification: in the INIT chunk. + * Tag : + */ + __u32 peer_vtag; + + /* The rest of these are not from the spec, but really need to + * be in the cookie. + */ + + /* My Tie Tag : Assist in discovering a restarting association. */ + __u32 my_ttag; + + /* Peer's Tie Tag: Assist in discovering a restarting association. */ + __u32 peer_ttag; + + /* When does this cookie expire? */ + struct timeval expiration; + + /* Number of inbound/outbound streams which are set + * and negotiated during the INIT process. + */ + __u16 sinit_num_ostreams; + __u16 sinit_max_instreams; + + /* This is the first sequence number I used. */ + __u32 initial_tsn; + + /* This holds the originating address of the INIT packet. */ + union sctp_addr peer_addr; + + /* IG Section 2.35.3 + * Include the source port of the INIT-ACK + */ + __u16 my_port; + + __u8 prsctp_capable; + + /* Padding for future use */ + __u8 padding; + + __u32 adaption_ind; + + + /* This is a shim for my peer's INIT packet, followed by + * a copy of the raw address list of the association. + * The length of the raw address list is saved in the + * raw_addr_list_len field, which will be used at the time when + * the association TCB is re-constructed from the cookie. + */ + __u32 raw_addr_list_len; + struct sctp_init_chunk peer_init[0]; +}; + + +/* The format of our cookie that we send to our peer. */ +struct sctp_signed_cookie { + __u8 signature[SCTP_SECRET_SIZE]; + struct sctp_cookie c; +}; + +/* This is another convenience type to allocate memory for address + * params for the maximum size and pass such structures around + * internally. + */ +union sctp_addr_param { + struct sctp_ipv4addr_param v4; + struct sctp_ipv6addr_param v6; +}; + +/* A convenience type to allow walking through the various + * parameters and avoid casting all over the place. + */ +union sctp_params { + void *v; + struct sctp_paramhdr *p; + struct sctp_cookie_preserve_param *life; + struct sctp_hostname_param *dns; + struct sctp_cookie_param *cookie; + struct sctp_supported_addrs_param *sat; + struct sctp_ipv4addr_param *v4; + struct sctp_ipv6addr_param *v6; + union sctp_addr_param *addr; + struct sctp_adaption_ind_param *aind; +}; + +/* RFC 2960. Section 3.3.5 Heartbeat. + * Heartbeat Information: variable length + * The Sender-specific Heartbeat Info field should normally include + * information about the sender's current time when this HEARTBEAT + * chunk is sent and the destination transport address to which this + * HEARTBEAT is sent (see Section 8.3). + */ +typedef struct sctp_sender_hb_info { + struct sctp_paramhdr param_hdr; + union sctp_addr daddr; + unsigned long sent_at; +} __attribute__((packed)) sctp_sender_hb_info_t; + +/* + * RFC 2960 1.3.2 Sequenced Delivery within Streams + * + * The term "stream" is used in SCTP to refer to a sequence of user + * messages that are to be delivered to the upper-layer protocol in + * order with respect to other messages within the same stream. This is + * in contrast to its usage in TCP, where it refers to a sequence of + * bytes (in this document a byte is assumed to be eight bits). + * ... + * + * This is the structure we use to track both our outbound and inbound + * SSN, or Stream Sequence Numbers. + */ + +struct sctp_stream { + __u16 *ssn; + unsigned int len; +}; + +struct sctp_ssnmap { + struct sctp_stream in; + struct sctp_stream out; + int malloced; +}; + +struct sctp_ssnmap *sctp_ssnmap_new(__u16 in, __u16 out, int gfp); +void sctp_ssnmap_free(struct sctp_ssnmap *map); +void sctp_ssnmap_clear(struct sctp_ssnmap *map); + +/* What is the current SSN number for this stream? */ +static inline __u16 sctp_ssn_peek(struct sctp_stream *stream, __u16 id) +{ + return stream->ssn[id]; +} + +/* Return the next SSN number for this stream. */ +static inline __u16 sctp_ssn_next(struct sctp_stream *stream, __u16 id) +{ + return stream->ssn[id]++; +} + +/* Skip over this ssn and all below. */ +static inline void sctp_ssn_skip(struct sctp_stream *stream, __u16 id, + __u16 ssn) +{ + stream->ssn[id] = ssn+1; +} + +/* + * Pointers to address related SCTP functions. + * (i.e. things that depend on the address family.) + */ +struct sctp_af { + int (*sctp_xmit) (struct sk_buff *skb, + struct sctp_transport *, + int ipfragok); + int (*setsockopt) (struct sock *sk, + int level, + int optname, + char __user *optval, + int optlen); + int (*getsockopt) (struct sock *sk, + int level, + int optname, + char __user *optval, + int __user *optlen); + struct dst_entry *(*get_dst) (struct sctp_association *asoc, + union sctp_addr *daddr, + union sctp_addr *saddr); + void (*get_saddr) (struct sctp_association *asoc, + struct dst_entry *dst, + union sctp_addr *daddr, + union sctp_addr *saddr); + void (*copy_addrlist) (struct list_head *, + struct net_device *); + void (*dst_saddr) (union sctp_addr *saddr, + struct dst_entry *dst, + unsigned short port); + int (*cmp_addr) (const union sctp_addr *addr1, + const union sctp_addr *addr2); + void (*addr_copy) (union sctp_addr *dst, + union sctp_addr *src); + void (*from_skb) (union sctp_addr *, + struct sk_buff *skb, + int saddr); + void (*from_sk) (union sctp_addr *, + struct sock *sk); + void (*to_sk_saddr) (union sctp_addr *, + struct sock *sk); + void (*to_sk_daddr) (union sctp_addr *, + struct sock *sk); + void (*from_addr_param) (union sctp_addr *, + union sctp_addr_param *, + __u16 port, int iif); + int (*to_addr_param) (const union sctp_addr *, + union sctp_addr_param *); + int (*addr_valid) (union sctp_addr *, + struct sctp_sock *); + sctp_scope_t (*scope) (union sctp_addr *); + void (*inaddr_any) (union sctp_addr *, unsigned short); + int (*is_any) (const union sctp_addr *); + int (*available) (union sctp_addr *, + struct sctp_sock *); + int (*skb_iif) (const struct sk_buff *sk); + int (*is_ce) (const struct sk_buff *sk); + void (*seq_dump_addr)(struct seq_file *seq, + union sctp_addr *addr); + __u16 net_header_len; + int sockaddr_len; + sa_family_t sa_family; + struct list_head list; +}; + +struct sctp_af *sctp_get_af_specific(sa_family_t); +int sctp_register_af(struct sctp_af *); + +/* Protocol family functions. */ +struct sctp_pf { + void (*event_msgname)(struct sctp_ulpevent *, char *, int *); + void (*skb_msgname) (struct sk_buff *, char *, int *); + int (*af_supported) (sa_family_t, struct sctp_sock *); + int (*cmp_addr) (const union sctp_addr *, + const union sctp_addr *, + struct sctp_sock *); + int (*bind_verify) (struct sctp_sock *, union sctp_addr *); + int (*send_verify) (struct sctp_sock *, union sctp_addr *); + int (*supported_addrs)(const struct sctp_sock *, __u16 *); + struct sock *(*create_accept_sk) (struct sock *sk, + struct sctp_association *asoc); + void (*addr_v4map) (struct sctp_sock *, union sctp_addr *); + struct sctp_af *af; +}; + + +/* Structure to track chunk fragments that have been acked, but peer + * fragments of the same message have not. + */ +struct sctp_datamsg { + /* Chunks waiting to be submitted to lower layer. */ + struct list_head chunks; + /* Chunks that have been transmitted. */ + struct list_head track; + /* Reference counting. */ + atomic_t refcnt; + /* When is this message no longer interesting to the peer? */ + unsigned long expires_at; + /* Did the messenge fail to send? */ + int send_error; + char send_failed; + /* Control whether chunks from this message can be abandoned. */ + char can_abandon; +}; + +struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *, + struct sctp_sndrcvinfo *, + struct msghdr *, int len); +void sctp_datamsg_put(struct sctp_datamsg *); +void sctp_datamsg_free(struct sctp_datamsg *); +void sctp_datamsg_track(struct sctp_chunk *); +void sctp_chunk_fail(struct sctp_chunk *, int error); +int sctp_chunk_abandoned(struct sctp_chunk *); + + +/* RFC2960 1.4 Key Terms + * + * o Chunk: A unit of information within an SCTP packet, consisting of + * a chunk header and chunk-specific content. + * + * As a matter of convenience, we remember the SCTP common header for + * each chunk as well as a few other header pointers... + */ +struct sctp_chunk { + /* These first three elements MUST PRECISELY match the first + * three elements of struct sk_buff. This allows us to reuse + * all the skb_* queue management functions. + */ + struct sctp_chunk *next; + struct sctp_chunk *prev; + struct sk_buff_head *list; + atomic_t refcnt; + + /* This is our link to the per-transport transmitted list. */ + struct list_head transmitted_list; + + /* This field is used by chunks that hold fragmented data. + * For the first fragment this is the list that holds the rest of + * fragments. For the remaining fragments, this is the link to the + * frag_list maintained in the first fragment. + */ + struct list_head frag_list; + + /* This points to the sk_buff containing the actual data. */ + struct sk_buff *skb; + + /* These are the SCTP headers by reverse order in a packet. + * Note that some of these may happen more than once. In that + * case, we point at the "current" one, whatever that means + * for that level of header. + */ + + /* We point this at the FIRST TLV parameter to chunk_hdr. */ + union sctp_params param_hdr; + union { + __u8 *v; + struct sctp_datahdr *data_hdr; + struct sctp_inithdr *init_hdr; + struct sctp_sackhdr *sack_hdr; + struct sctp_heartbeathdr *hb_hdr; + struct sctp_sender_hb_info *hbs_hdr; + struct sctp_shutdownhdr *shutdown_hdr; + struct sctp_signed_cookie *cookie_hdr; + struct sctp_ecnehdr *ecne_hdr; + struct sctp_cwrhdr *ecn_cwr_hdr; + struct sctp_errhdr *err_hdr; + struct sctp_addiphdr *addip_hdr; + struct sctp_fwdtsn_hdr *fwdtsn_hdr; + } subh; + + __u8 *chunk_end; + + struct sctp_chunkhdr *chunk_hdr; + struct sctphdr *sctp_hdr; + + /* This needs to be recoverable for SCTP_SEND_FAILED events. */ + struct sctp_sndrcvinfo sinfo; + + /* Which association does this belong to? */ + struct sctp_association *asoc; + + /* What endpoint received this chunk? */ + struct sctp_ep_common *rcvr; + + /* We fill this in if we are calculating RTT. */ + unsigned long sent_at; + + /* What is the origin IP address for this chunk? */ + union sctp_addr source; + /* Destination address for this chunk. */ + union sctp_addr dest; + + /* For outbound message, track all fragments for SEND_FAILED. */ + struct sctp_datamsg *msg; + + /* For an inbound chunk, this tells us where it came from. + * For an outbound chunk, it tells us where we'd like it to + * go. It is NULL if we have no preference. + */ + struct sctp_transport *transport; + + __u8 rtt_in_progress; /* Is this chunk used for RTT calculation? */ + __u8 resent; /* Has this chunk ever been retransmitted. */ + __u8 has_tsn; /* Does this chunk have a TSN yet? */ + __u8 has_ssn; /* Does this chunk have a SSN yet? */ + __u8 singleton; /* Was this the only chunk in the packet? */ + __u8 end_of_packet; /* Was this the last chunk in the packet? */ + __u8 ecn_ce_done; /* Have we processed the ECN CE bit? */ + __u8 pdiscard; /* Discard the whole packet now? */ + __u8 tsn_gap_acked; /* Is this chunk acked by a GAP ACK? */ + __u8 fast_retransmit; /* Is this chunk fast retransmitted? */ + __u8 tsn_missing_report; /* Data chunk missing counter. */ +}; + +void sctp_chunk_hold(struct sctp_chunk *); +void sctp_chunk_put(struct sctp_chunk *); +int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len, + struct iovec *data); +void sctp_chunk_free(struct sctp_chunk *); +void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data); +struct sctp_chunk *sctp_chunkify(struct sk_buff *, + const struct sctp_association *, + struct sock *); +void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *, + union sctp_addr *); +const union sctp_addr *sctp_source(const struct sctp_chunk *chunk); + +/* This is a structure for holding either an IPv6 or an IPv4 address. */ +/* sin_family -- AF_INET or AF_INET6 + * sin_port -- ordinary port number + * sin_addr -- cast to either (struct in_addr) or (struct in6_addr) + */ +struct sctp_sockaddr_entry { + struct list_head list; + union sctp_addr a; +}; + +typedef struct sctp_chunk *(sctp_packet_phandler_t)(struct sctp_association *); + +/* This structure holds lists of chunks as we are assembling for + * transmission. + */ +struct sctp_packet { + /* These are the SCTP header values (host order) for the packet. */ + __u16 source_port; + __u16 destination_port; + __u32 vtag; + + /* This contains the payload chunks. */ + struct sk_buff_head chunks; + + /* This is the overhead of the sctp and ip headers. */ + size_t overhead; + /* This is the total size of all chunks INCLUDING padding. */ + size_t size; + + /* The packet is destined for this transport address. + * The function we finally use to pass down to the next lower + * layer lives in the transport structure. + */ + struct sctp_transport *transport; + + /* This packet contains a COOKIE-ECHO chunk. */ + char has_cookie_echo; + + /* This packet containsa SACK chunk. */ + char has_sack; + + /* SCTP cannot fragment this packet. So let ip fragment it. */ + char ipfragok; + + int malloced; +}; + +struct sctp_packet *sctp_packet_init(struct sctp_packet *, + struct sctp_transport *, + __u16 sport, __u16 dport); +struct sctp_packet *sctp_packet_config(struct sctp_packet *, __u32 vtag, int); +sctp_xmit_t sctp_packet_transmit_chunk(struct sctp_packet *, + struct sctp_chunk *); +sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *, + struct sctp_chunk *); +int sctp_packet_transmit(struct sctp_packet *); +void sctp_packet_free(struct sctp_packet *); + +static inline int sctp_packet_empty(struct sctp_packet *packet) +{ + return (packet->size == packet->overhead); +} + +/* This represents a remote transport address. + * For local transport addresses, we just use union sctp_addr. + * + * RFC2960 Section 1.4 Key Terms + * + * o Transport address: A Transport Address is traditionally defined + * by Network Layer address, Transport Layer protocol and Transport + * Layer port number. In the case of SCTP running over IP, a + * transport address is defined by the combination of an IP address + * and an SCTP port number (where SCTP is the Transport protocol). + * + * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control + * + * o The sender keeps a separate congestion control parameter set for + * each of the destination addresses it can send to (not each + * source-destination pair but for each destination). The parameters + * should decay if the address is not used for a long enough time + * period. + * + */ +struct sctp_transport { + /* A list of transports. */ + struct list_head transports; + + /* Reference counting. */ + atomic_t refcnt; + int dead; + + /* This is the peer's IP address and port. */ + union sctp_addr ipaddr; + + /* These are the functions we call to handle LLP stuff. */ + struct sctp_af *af_specific; + + /* Which association do we belong to? */ + struct sctp_association *asoc; + + /* RFC2960 + * + * 12.3 Per Transport Address Data + * + * For each destination transport address in the peer's + * address list derived from the INIT or INIT ACK chunk, a + * number of data elements needs to be maintained including: + */ + __u32 rtt; /* This is the most recent RTT. */ + + /* RTO : The current retransmission timeout value. */ + __u32 rto; + + /* RTTVAR : The current RTT variation. */ + __u32 rttvar; + + /* SRTT : The current smoothed round trip time. */ + __u32 srtt; + + /* RTO-Pending : A flag used to track if one of the DATA + * chunks sent to this address is currently being + * used to compute a RTT. If this flag is 0, + * the next DATA chunk sent to this destination + * should be used to compute a RTT and this flag + * should be set. Every time the RTT + * calculation completes (i.e. the DATA chunk + * is SACK'd) clear this flag. + */ + int rto_pending; + + /* + * These are the congestion stats. + */ + /* cwnd : The current congestion window. */ + __u32 cwnd; /* This is the actual cwnd. */ + + /* ssthresh : The current slow start threshold value. */ + __u32 ssthresh; + + /* partial : The tracking method for increase of cwnd when in + * bytes acked : congestion avoidance mode (see Section 6.2.2) + */ + __u32 partial_bytes_acked; + + /* Data that has been sent, but not acknowledged. */ + __u32 flight_size; + + /* PMTU : The current known path MTU. */ + __u32 pmtu; + + /* Destination */ + struct dst_entry *dst; + /* Source address. */ + union sctp_addr saddr; + + /* When was the last time(in jiffies) that a data packet was sent on + * this transport? This is used to adjust the cwnd when the transport + * becomes inactive. + */ + unsigned long last_time_used; + + /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to + * the destination address every heartbeat interval. + */ + int hb_interval; + + /* When was the last time (in jiffies) that we heard from this + * transport? We use this to pick new active and retran paths. + */ + unsigned long last_time_heard; + + /* Last time(in jiffies) when cwnd is reduced due to the congestion + * indication based on ECNE chunk. + */ + unsigned long last_time_ecne_reduced; + + /* active : The current active state of this destination, + * : i.e. DOWN, UP, etc. + */ + int active; + + /* hb_allowed : The current heartbeat state of this destination, + * : i.e. ALLOW-HB, NO-HEARTBEAT, etc. + */ + int hb_allowed; + + /* These are the error stats for this destination. */ + + /* Error count : The current error count for this destination. */ + unsigned short error_count; + + /* This is the max_retrans value for the transport and will + * be initialized to proto.max_retrans.path. This can be changed + * using SCTP_SET_PEER_ADDR_PARAMS socket option. + */ + int max_retrans; + + /* Per : A timer used by each destination. + * Destination : + * Timer : + * + * [Everywhere else in the text this is called T3-rtx. -ed] + */ + struct timer_list T3_rtx_timer; + + /* Heartbeat timer is per destination. */ + struct timer_list hb_timer; + + /* Since we're using per-destination retransmission timers + * (see above), we're also using per-destination "transmitted" + * queues. This probably ought to be a private struct + * accessible only within the outqueue, but it's not, yet. + */ + struct list_head transmitted; + + /* We build bundle-able packets for this transport here. */ + struct sctp_packet packet; + + /* This is the list of transports that have chunks to send. */ + struct list_head send_ready; + + int malloced; /* Is this structure kfree()able? */ + + /* State information saved for SFR_CACC algorithm. The key + * idea in SFR_CACC is to maintain state at the sender on a + * per-destination basis when a changeover happens. + * char changeover_active; + * char cycling_changeover; + * __u32 next_tsn_at_change; + * char cacc_saw_newack; + */ + struct { + /* An unsigned integer, which stores the next TSN to be + * used by the sender, at the moment of changeover. + */ + __u32 next_tsn_at_change; + + /* A flag which indicates the occurrence of a changeover */ + char changeover_active; + + /* A flag which indicates whether the change of primary is + * the first switch to this destination address during an + * active switch. + */ + char cycling_changeover; + + /* A temporary flag, which is used during the processing of + * a SACK to estimate the causative TSN(s)'s group. + */ + char cacc_saw_newack; + } cacc; +}; + +struct sctp_transport *sctp_transport_new(const union sctp_addr *, int); +void sctp_transport_set_owner(struct sctp_transport *, + struct sctp_association *); +void sctp_transport_route(struct sctp_transport *, union sctp_addr *, + struct sctp_sock *); +void sctp_transport_pmtu(struct sctp_transport *); +void sctp_transport_free(struct sctp_transport *); +void sctp_transport_reset_timers(struct sctp_transport *); +void sctp_transport_hold(struct sctp_transport *); +void sctp_transport_put(struct sctp_transport *); +void sctp_transport_update_rto(struct sctp_transport *, __u32); +void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32); +void sctp_transport_lower_cwnd(struct sctp_transport *, sctp_lower_cwnd_t); +unsigned long sctp_transport_timeout(struct sctp_transport *); + + +/* This is the structure we use to queue packets as they come into + * SCTP. We write packets to it and read chunks from it. + */ +struct sctp_inq { + /* This is actually a queue of sctp_chunk each + * containing a partially decoded packet. + */ + struct sk_buff_head in; + /* This is the packet which is currently off the in queue and is + * being worked on through the inbound chunk processing. + */ + struct sctp_chunk *in_progress; + + /* This is the delayed task to finish delivering inbound + * messages. + */ + struct work_struct immediate; + + int malloced; /* Is this structure kfree()able? */ +}; + +void sctp_inq_init(struct sctp_inq *); +void sctp_inq_free(struct sctp_inq *); +void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet); +struct sctp_chunk *sctp_inq_pop(struct sctp_inq *); +void sctp_inq_set_th_handler(struct sctp_inq *, void (*)(void *), void *); + +/* This is the structure we use to hold outbound chunks. You push + * chunks in and they automatically pop out the other end as bundled + * packets (it calls (*output_handler)()). + * + * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1, + * and 8.2 of the v13 draft. + * + * It handles retransmissions. The connection to the timeout portion + * of the state machine is through sctp_..._timeout() and timeout_handler. + * + * If you feed it SACKs, it will eat them. + * + * If you give it big chunks, it will fragment them. + * + * It assigns TSN's to data chunks. This happens at the last possible + * instant before transmission. + * + * When free()'d, it empties itself out via output_handler(). + */ +struct sctp_outq { + struct sctp_association *asoc; + + /* Data pending that has never been transmitted. */ + struct sk_buff_head out; + + unsigned out_qlen; /* Total length of queued data chunks. */ + + /* Error of send failed, may used in SCTP_SEND_FAILED event. */ + unsigned error; + + /* These are control chunks we want to send. */ + struct sk_buff_head control; + + /* These are chunks that have been sacked but are above the + * CTSN, or cumulative tsn ack point. + */ + struct list_head sacked; + + /* Put chunks on this list to schedule them for + * retransmission. + */ + struct list_head retransmit; + + /* Put chunks on this list to save them for FWD TSN processing as + * they were abandoned. + */ + struct list_head abandoned; + + /* How many unackd bytes do we have in-flight? */ + __u32 outstanding_bytes; + + /* Corked? */ + char cork; + + /* Is this structure empty? */ + char empty; + + /* Are we kfree()able? */ + char malloced; +}; + +void sctp_outq_init(struct sctp_association *, struct sctp_outq *); +void sctp_outq_teardown(struct sctp_outq *); +void sctp_outq_free(struct sctp_outq*); +int sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk); +int sctp_outq_flush(struct sctp_outq *, int); +int sctp_outq_sack(struct sctp_outq *, struct sctp_sackhdr *); +int sctp_outq_is_empty(const struct sctp_outq *); +void sctp_outq_restart(struct sctp_outq *); + +void sctp_retransmit(struct sctp_outq *, struct sctp_transport *, + sctp_retransmit_reason_t); +void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8); +int sctp_outq_uncork(struct sctp_outq *); +/* Uncork and flush an outqueue. */ +static inline void sctp_outq_cork(struct sctp_outq *q) +{ + q->cork = 1; +} + +/* These bind address data fields common between endpoints and associations */ +struct sctp_bind_addr { + + /* RFC 2960 12.1 Parameters necessary for the SCTP instance + * + * SCTP Port: The local SCTP port number the endpoint is + * bound to. + */ + __u16 port; + + /* RFC 2960 12.1 Parameters necessary for the SCTP instance + * + * Address List: The list of IP addresses that this instance + * has bound. This information is passed to one's + * peer(s) in INIT and INIT ACK chunks. + */ + struct list_head address_list; + + int malloced; /* Are we kfree()able? */ +}; + +void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port); +void sctp_bind_addr_free(struct sctp_bind_addr *); +int sctp_bind_addr_copy(struct sctp_bind_addr *dest, + const struct sctp_bind_addr *src, + sctp_scope_t scope, int gfp,int flags); +int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *, + int gfp); +int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *); +int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *, + struct sctp_sock *); +union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp, + const union sctp_addr *addrs, + int addrcnt, + struct sctp_sock *opt); +union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp, + int *addrs_len, int gfp); +int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len, + __u16 port, int gfp); + +sctp_scope_t sctp_scope(const union sctp_addr *); +int sctp_in_scope(const union sctp_addr *addr, const sctp_scope_t scope); +int sctp_is_any(const union sctp_addr *addr); +int sctp_addr_is_valid(const union sctp_addr *addr); + + +/* What type of endpoint? */ +typedef enum { + SCTP_EP_TYPE_SOCKET, + SCTP_EP_TYPE_ASSOCIATION, +} sctp_endpoint_type_t; + +/* + * A common base class to bridge the implmentation view of a + * socket (usually listening) endpoint versus an association's + * local endpoint. + * This common structure is useful for several purposes: + * 1) Common interface for lookup routines. + * a) Subfunctions work for either endpoint or association + * b) Single interface to lookup allows hiding the lookup lock rather + * than acquiring it externally. + * 2) Common interface for the inbound chunk handling/state machine. + * 3) Common object handling routines for reference counting, etc. + * 4) Disentangle association lookup from endpoint lookup, where we + * do not have to find our endpoint to find our association. + * + */ + +struct sctp_ep_common { + /* Fields to help us manage our entries in the hash tables. */ + struct sctp_ep_common *next; + struct sctp_ep_common **pprev; + int hashent; + + /* Runtime type information. What kind of endpoint is this? */ + sctp_endpoint_type_t type; + + /* Some fields to help us manage this object. + * refcnt - Reference count access to this object. + * dead - Do not attempt to use this object. + * malloced - Do we need to kfree this object? + */ + atomic_t refcnt; + char dead; + char malloced; + + /* What socket does this endpoint belong to? */ + struct sock *sk; + + /* This is where we receive inbound chunks. */ + struct sctp_inq inqueue; + + /* This substructure includes the defining parameters of the + * endpoint: + * bind_addr.port is our shared port number. + * bind_addr.address_list is our set of local IP addresses. + */ + struct sctp_bind_addr bind_addr; + + /* Protection during address list comparisons. */ + rwlock_t addr_lock; +}; + + +/* RFC Section 1.4 Key Terms + * + * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a + * multi-homed host, an SCTP endpoint is represented to its peers as a + * combination of a set of eligible destination transport addresses to + * which SCTP packets can be sent and a set of eligible source + * transport addresses from which SCTP packets can be received. + * All transport addresses used by an SCTP endpoint must use the + * same port number, but can use multiple IP addresses. A transport + * address used by an SCTP endpoint must not be used by another + * SCTP endpoint. In other words, a transport address is unique + * to an SCTP endpoint. + * + * From an implementation perspective, each socket has one of these. + * A TCP-style socket will have exactly one association on one of + * these. An UDP-style socket will have multiple associations hanging + * off one of these. + */ + +struct sctp_endpoint { + /* Common substructure for endpoint and association. */ + struct sctp_ep_common base; + + /* Associations: A list of current associations and mappings + * to the data consumers for each association. This + * may be in the form of a hash table or other + * implementation dependent structure. The data + * consumers may be process identification + * information such as file descriptors, named pipe + * pointer, or table pointers dependent on how SCTP + * is implemented. + */ + /* This is really a list of struct sctp_association entries. */ + struct list_head asocs; + + /* Secret Key: A secret key used by this endpoint to compute + * the MAC. This SHOULD be a cryptographic quality + * random number with a sufficient length. + * Discussion in [RFC1750] can be helpful in + * selection of the key. + */ + __u8 secret_key[SCTP_HOW_MANY_SECRETS][SCTP_SECRET_SIZE]; + int current_key; + int last_key; + int key_changed_at; + + /* Default timeouts. */ + int timeouts[SCTP_NUM_TIMEOUT_TYPES]; + + /* Various thresholds. */ + + /* Name for debugging output... */ + char *debug_name; +}; + +/* Recover the outter endpoint structure. */ +static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base) +{ + struct sctp_endpoint *ep; + + ep = container_of(base, struct sctp_endpoint, base); + return ep; +} + +/* These are function signatures for manipulating endpoints. */ +struct sctp_endpoint *sctp_endpoint_new(struct sock *, int); +void sctp_endpoint_free(struct sctp_endpoint *); +void sctp_endpoint_put(struct sctp_endpoint *); +void sctp_endpoint_hold(struct sctp_endpoint *); +void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *); +struct sctp_association *sctp_endpoint_lookup_assoc( + const struct sctp_endpoint *ep, + const union sctp_addr *paddr, + struct sctp_transport **); +int sctp_endpoint_is_peeled_off(struct sctp_endpoint *, + const union sctp_addr *); +struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *, + const union sctp_addr *); +int sctp_has_association(const union sctp_addr *laddr, + const union sctp_addr *paddr); + +int sctp_verify_init(const struct sctp_association *asoc, sctp_cid_t, + sctp_init_chunk_t *peer_init, struct sctp_chunk *chunk, + struct sctp_chunk **err_chunk); +int sctp_process_init(struct sctp_association *, sctp_cid_t cid, + const union sctp_addr *peer, + sctp_init_chunk_t *init, int gfp); +__u32 sctp_generate_tag(const struct sctp_endpoint *); +__u32 sctp_generate_tsn(const struct sctp_endpoint *); + + +/* RFC2960 + * + * 12. Recommended Transmission Control Block (TCB) Parameters + * + * This section details a recommended set of parameters that should + * be contained within the TCB for an implementation. This section is + * for illustrative purposes and should not be deemed as requirements + * on an implementation or as an exhaustive list of all parameters + * inside an SCTP TCB. Each implementation may need its own additional + * parameters for optimization. + */ + + +/* Here we have information about each individual association. */ +struct sctp_association { + + /* A base structure common to endpoint and association. + * In this context, it represents the associations's view + * of the local endpoint of the association. + */ + struct sctp_ep_common base; + + /* Associations on the same socket. */ + struct list_head asocs; + + /* association id. */ + sctp_assoc_t assoc_id; + + /* This is our parent endpoint. */ + struct sctp_endpoint *ep; + + /* These are those association elements needed in the cookie. */ + struct sctp_cookie c; + + /* This is all information about our peer. */ + struct { + /* rwnd + * + * Peer Rwnd : Current calculated value of the peer's rwnd. + */ + __u32 rwnd; + + /* transport_addr_list + * + * Peer : A list of SCTP transport addresses that the + * Transport : peer is bound to. This information is derived + * Address : from the INIT or INIT ACK and is used to + * List : associate an inbound packet with a given + * : association. Normally this information is + * : hashed or keyed for quick lookup and access + * : of the TCB. + * + * It is a list of SCTP_transport's. + */ + struct list_head transport_addr_list; + + /* port + * The transport layer port number. + */ + __u16 port; + + /* primary_path + * + * Primary : This is the current primary destination + * Path : transport address of the peer endpoint. It + * : may also specify a source transport address + * : on this endpoint. + * + * All of these paths live on transport_addr_list. + * + * At the bakeoffs, we discovered that the intent of + * primaryPath is that it only changes when the ULP + * asks to have it changed. We add the activePath to + * designate the connection we are currently using to + * transmit new data and most control chunks. + */ + struct sctp_transport *primary_path; + + /* Cache the primary path address here, when we + * need a an address for msg_name. + */ + union sctp_addr primary_addr; + + /* active_path + * The path that we are currently using to + * transmit new data and most control chunks. + */ + struct sctp_transport *active_path; + + /* retran_path + * + * RFC2960 6.4 Multi-homed SCTP Endpoints + * ... + * Furthermore, when its peer is multi-homed, an + * endpoint SHOULD try to retransmit a chunk to an + * active destination transport address that is + * different from the last destination address to + * which the DATA chunk was sent. + */ + struct sctp_transport *retran_path; + + /* Pointer to last transport I have sent on. */ + struct sctp_transport *last_sent_to; + + /* This is the last transport I have received DATA on. */ + struct sctp_transport *last_data_from; + + /* + * Mapping An array of bits or bytes indicating which out of + * Array order TSN's have been received (relative to the + * Last Rcvd TSN). If no gaps exist, i.e. no out of + * order packets have been received, this array + * will be set to all zero. This structure may be + * in the form of a circular buffer or bit array. + * + * Last Rcvd : This is the last TSN received in + * TSN : sequence. This value is set initially by + * : taking the peer's Initial TSN, received in + * : the INIT or INIT ACK chunk, and subtracting + * : one from it. + * + * Throughout most of the specification this is called the + * "Cumulative TSN ACK Point". In this case, we + * ignore the advice in 12.2 in favour of the term + * used in the bulk of the text. This value is hidden + * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn(). + */ + struct sctp_tsnmap tsn_map; + __u8 _map[sctp_tsnmap_storage_size(SCTP_TSN_MAP_SIZE)]; + + /* Ack State : This flag indicates if the next received + * : packet is to be responded to with a + * : SACK. This is initializedto 0. When a packet + * : is received it is incremented. If this value + * : reaches 2 or more, a SACK is sent and the + * : value is reset to 0. Note: This is used only + * : when no DATA chunks are received out of + * : order. When DATA chunks are out of order, + * : SACK's are not delayed (see Section 6). + */ + __u8 sack_needed; /* Do we need to sack the peer? */ + + /* These are capabilities which our peer advertised. */ + __u8 ecn_capable; /* Can peer do ECN? */ + __u8 ipv4_address; /* Peer understands IPv4 addresses? */ + __u8 ipv6_address; /* Peer understands IPv6 addresses? */ + __u8 hostname_address;/* Peer understands DNS addresses? */ + __u8 asconf_capable; /* Does peer support ADDIP? */ + __u8 prsctp_capable; /* Can peer do PR-SCTP? */ + + __u32 adaption_ind; /* Adaption Code point. */ + + /* This mask is used to disable sending the ASCONF chunk + * with specified parameter to peer. + */ + __u16 addip_disabled_mask; + + struct sctp_inithdr i; + int cookie_len; + void *cookie; + + /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. + * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the + * Initial TSN Value minus 1 + */ + __u32 addip_serial; + } peer; + + /* State : A state variable indicating what state the + * : association is in, i.e. COOKIE-WAIT, + * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING, + * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT. + * + * Note: No "CLOSED" state is illustrated since if a + * association is "CLOSED" its TCB SHOULD be removed. + * + * In this implementation we DO have a CLOSED + * state which is used during initiation and shutdown. + * + * State takes values from SCTP_STATE_*. + */ + sctp_state_t state; + + /* The cookie life I award for any cookie. */ + struct timeval cookie_life; + + /* Overall : The overall association error count. + * Error Count : [Clear this any time I get something.] + */ + int overall_error_count; + + /* These are the association's initial, max, and min RTO values. + * These values will be initialized by system defaults, but can + * be modified via the SCTP_RTOINFO socket option. + */ + __u32 rto_initial; + __u32 rto_max; + __u32 rto_min; + + /* Maximum number of new data packets that can be sent in a burst. */ + int max_burst; + + /* This is the max_retrans value for the association. This value will + * be initialized initialized from system defaults, but can be + * modified by the SCTP_ASSOCINFO socket option. + */ + int max_retrans; + + /* Maximum number of times the endpoint will retransmit INIT */ + __u16 max_init_attempts; + + /* How many times have we resent an INIT? */ + __u16 init_retries; + + /* The largest timeout or RTO value to use in attempting an INIT */ + __u16 max_init_timeo; + + int timeouts[SCTP_NUM_TIMEOUT_TYPES]; + struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES]; + + /* Transport to which SHUTDOWN chunk was last sent. */ + struct sctp_transport *shutdown_last_sent_to; + + /* Next TSN : The next TSN number to be assigned to a new + * : DATA chunk. This is sent in the INIT or INIT + * : ACK chunk to the peer and incremented each + * : time a DATA chunk is assigned a TSN + * : (normally just prior to transmit or during + * : fragmentation). + */ + __u32 next_tsn; + + /* + * Last Rcvd : This is the last TSN received in sequence. This value + * TSN : is set initially by taking the peer's Initial TSN, + * : received in the INIT or INIT ACK chunk, and + * : subtracting one from it. + * + * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point. + */ + + __u32 ctsn_ack_point; + + /* PR-SCTP Advanced.Peer.Ack.Point */ + __u32 adv_peer_ack_point; + + /* Highest TSN that is acknowledged by incoming SACKs. */ + __u32 highest_sacked; + + /* The number of unacknowledged data chunks. Reported through + * the SCTP_STATUS sockopt. + */ + __u16 unack_data; + + /* This is the association's receive buffer space. This value is used + * to set a_rwnd field in an INIT or a SACK chunk. + */ + __u32 rwnd; + + /* This is the last advertised value of rwnd over a SACK chunk. */ + __u32 a_rwnd; + + /* Number of bytes by which the rwnd has slopped. The rwnd is allowed + * to slop over a maximum of the association's frag_point. + */ + __u32 rwnd_over; + + /* This is the sndbuf size in use for the association. + * This corresponds to the sndbuf size for the association, + * as specified in the sk->sndbuf. + */ + int sndbuf_used; + + /* This is the wait queue head for send requests waiting on + * the association sndbuf space. + */ + wait_queue_head_t wait; + + /* Association : The smallest PMTU discovered for all of the + * PMTU : peer's transport addresses. + */ + __u32 pmtu; + + /* The message size at which SCTP fragmentation will occur. */ + __u32 frag_point; + + /* Currently only one counter is used to count INIT errors. */ + int counters[SCTP_NUMBER_COUNTERS]; + + /* Default send parameters. */ + __u16 default_stream; + __u16 default_flags; + __u32 default_ppid; + __u32 default_context; + __u32 default_timetolive; + + /* This tracks outbound ssn for a given stream. */ + struct sctp_ssnmap *ssnmap; + + /* All outbound chunks go through this structure. */ + struct sctp_outq outqueue; + + /* A smart pipe that will handle reordering and fragmentation, + * as well as handle passing events up to the ULP. + */ + struct sctp_ulpq ulpq; + + /* Last TSN that caused an ECNE Chunk to be sent. */ + __u32 last_ecne_tsn; + + /* Last TSN that caused a CWR Chunk to be sent. */ + __u32 last_cwr_tsn; + + /* How many duplicated TSNs have we seen? */ + int numduptsns; + + /* Number of seconds of idle time before an association is closed. */ + __u32 autoclose; + + /* These are to support + * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses + * and Enforcement of Flow and Message Limits" + * <draft-ietf-tsvwg-addip-sctp-02.txt> + * or "ADDIP" for short. + */ + + + + /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks + * + * R1) One and only one ASCONF Chunk MAY be in transit and + * unacknowledged at any one time. If a sender, after sending + * an ASCONF chunk, decides it needs to transfer another + * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk + * returns from the previous ASCONF Chunk before sending a + * subsequent ASCONF. Note this restriction binds each side, + * so at any time two ASCONF may be in-transit on any given + * association (one sent from each endpoint). + * + * [This is our one-and-only-one ASCONF in flight. If we do + * not have an ASCONF in flight, this is NULL.] + */ + struct sctp_chunk *addip_last_asconf; + + /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. + * + * IMPLEMENTATION NOTE: As an optimization a receiver may wish + * to save the last ASCONF-ACK for some predetermined period + * of time and instead of re-processing the ASCONF (with the + * same serial number) it may just re-transmit the + * ASCONF-ACK. It may wish to use the arrival of a new serial + * number to discard the previously saved ASCONF-ACK or any + * other means it may choose to expire the saved ASCONF-ACK. + * + * [This is our saved ASCONF-ACK. We invalidate it when a new + * ASCONF serial number arrives.] + */ + struct sctp_chunk *addip_last_asconf_ack; + + /* These ASCONF chunks are waiting to be sent. + * + * These chunaks can't be pushed to outqueue until receiving + * ASCONF_ACK for the previous ASCONF indicated by + * addip_last_asconf, so as to guarantee that only one ASCONF + * is in flight at any time. + * + * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks + * + * In defining the ASCONF Chunk transfer procedures, it is + * essential that these transfers MUST NOT cause congestion + * within the network. To achieve this, we place these + * restrictions on the transfer of ASCONF Chunks: + * + * R1) One and only one ASCONF Chunk MAY be in transit and + * unacknowledged at any one time. If a sender, after sending + * an ASCONF chunk, decides it needs to transfer another + * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk + * returns from the previous ASCONF Chunk before sending a + * subsequent ASCONF. Note this restriction binds each side, + * so at any time two ASCONF may be in-transit on any given + * association (one sent from each endpoint). + * + * + * [I really think this is EXACTLY the sort of intelligence + * which already resides in sctp_outq. Please move this + * queue and its supporting logic down there. --piggy] + */ + struct sk_buff_head addip_chunks; + + /* ADDIP Section 4.1 ASCONF Chunk Procedures + * + * A2) A serial number should be assigned to the Chunk. The + * serial number SHOULD be a monotonically increasing + * number. The serial number SHOULD be initialized at + * the start of the association to the same value as the + * Initial TSN and every time a new ASCONF chunk is created + * it is incremented by one after assigning the serial number + * to the newly created chunk. + * + * ADDIP + * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF) + * + * Serial Number : 32 bits (unsigned integer) + * + * This value represents a Serial Number for the ASCONF + * Chunk. The valid range of Serial Number is from 0 to + * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0 + * after reaching 4294967295. + */ + __u32 addip_serial; + + /* Need to send an ECNE Chunk? */ + char need_ecne; + + /* Is it a temporary association? */ + char temp; +}; + + +/* An eyecatcher for determining if we are really looking at an + * association data structure. + */ +enum { + SCTP_ASSOC_EYECATCHER = 0xa550c123, +}; + +/* Recover the outter association structure. */ +static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base) +{ + struct sctp_association *asoc; + + asoc = container_of(base, struct sctp_association, base); + return asoc; +} + +/* These are function signatures for manipulating associations. */ + + +struct sctp_association * +sctp_association_new(const struct sctp_endpoint *, const struct sock *, + sctp_scope_t scope, int gfp); +void sctp_association_free(struct sctp_association *); +void sctp_association_put(struct sctp_association *); +void sctp_association_hold(struct sctp_association *); + +struct sctp_transport *sctp_assoc_choose_shutdown_transport( + struct sctp_association *); +void sctp_assoc_update_retran_path(struct sctp_association *); +struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *, + const union sctp_addr *); +int sctp_assoc_lookup_laddr(struct sctp_association *asoc, + const union sctp_addr *laddr); +struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *, + const union sctp_addr *address, + const int gfp); +void sctp_assoc_del_peer(struct sctp_association *asoc, + const union sctp_addr *addr); +void sctp_assoc_control_transport(struct sctp_association *, + struct sctp_transport *, + sctp_transport_cmd_t, sctp_sn_error_t); +struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32); +struct sctp_transport *sctp_assoc_is_match(struct sctp_association *, + const union sctp_addr *, + const union sctp_addr *); +void sctp_assoc_migrate(struct sctp_association *, struct sock *); +void sctp_assoc_update(struct sctp_association *old, + struct sctp_association *new); + +__u32 sctp_association_get_next_tsn(struct sctp_association *); + +void sctp_assoc_sync_pmtu(struct sctp_association *); +void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned); +void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned); +void sctp_assoc_set_primary(struct sctp_association *, + struct sctp_transport *); +int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *, int); +int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *, + struct sctp_cookie*, int gfp); + +int sctp_cmp_addr_exact(const union sctp_addr *ss1, + const union sctp_addr *ss2); +struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc); + +/* A convenience structure to parse out SCTP specific CMSGs. */ +typedef struct sctp_cmsgs { + struct sctp_initmsg *init; + struct sctp_sndrcvinfo *info; +} sctp_cmsgs_t; + +/* Structure for tracking memory objects */ +typedef struct { + char *label; + atomic_t *counter; +} sctp_dbg_objcnt_entry_t; + +#endif /* __sctp_structs_h__ */ |