--- /dev/null
+/* 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 addresses:
+ * lksctp developers <linux-sctp@vger.kernel.org>
+ *
+ * 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>
+ */
+
+#ifndef __sctp_structs_h__
+#define __sctp_structs_h__
+
+#include <linux/ktime.h>
+#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 <linux/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. */
+#include <net/sctp/auth.h> /* We need auth specific 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;
+struct crypto_hash;
+
+
+#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 hlist_node node;
+ struct hlist_head owner;
+ struct net *net;
+};
+
+struct sctp_bind_hashbucket {
+ spinlock_t lock;
+ struct hlist_head chain;
+};
+
+/* Used for hashing all associations. */
+struct sctp_hashbucket {
+ rwlock_t lock;
+ struct hlist_head chain;
+} __attribute__((__aligned__(8)));
+
+
+/* The SCTP globals structure. */
+extern struct sctp_globals {
+ /* 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. */
+ struct sctp_hashbucket *ep_hashtable;
+ /* This is the hash of all associations. */
+ struct sctp_hashbucket *assoc_hashtable;
+ /* This is the sctp port control hash. */
+ struct sctp_bind_hashbucket *port_hashtable;
+
+ /* Sizes of above hashtables. */
+ int ep_hashsize;
+ int assoc_hashsize;
+ int port_hashsize;
+
+ /* Default initialization values to be applied to new associations. */
+ __u16 max_instreams;
+ __u16 max_outstreams;
+
+ /* Flag to indicate whether computing and verifying checksum
+ * is disabled. */
+ bool checksum_disable;
+} sctp_globals;
+
+#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_hashtable (sctp_globals.port_hashtable)
+#define sctp_checksum_disable (sctp_globals.checksum_disable)
+
+/* 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_hash *hmac;
+ char *sctp_hmac_alg;
+
+ /* 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;
+ __u32 default_rcv_context;
+ int max_burst;
+
+ /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
+ * the destination address every heartbeat interval. This value
+ * will be inherited by all new associations.
+ */
+ __u32 hbinterval;
+
+ /* This is the max_retrans value for new associations. */
+ __u16 pathmaxrxt;
+
+ /* The initial Path MTU to use for new associations. */
+ __u32 pathmtu;
+
+ /* The default SACK delay timeout for new associations. */
+ __u32 sackdelay;
+ __u32 sackfreq;
+
+ /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
+ __u32 param_flags;
+
+ 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 v4mapped;
+ __u8 frag_interleave;
+ __u32 adaptation_ind;
+ __u32 pd_point;
+ __u8 recvrcvinfo;
+ __u8 recvnxtinfo;
+
+ atomic_t pd_mode;
+ /* Receive to here while partial delivery is in effect. */
+ struct sk_buff_head pd_lobby;
+
+ /* These must be the last fields, as they will skipped on copies,
+ * like on accept and peeloff operations
+ */
+ struct list_head auto_asconf_list;
+ int do_auto_asconf;
+};
+
+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 IS_ENABLED(CONFIG_IPV6)
+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? */
+ ktime_t 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 adaptation_ind;
+
+ __u8 auth_random[sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH];
+ __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2];
+ __u8 auth_chunks[sizeof(sctp_paramhdr_t) + SCTP_AUTH_MAX_CHUNKS];
+
+ /* 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];
+ __u32 __pad; /* force sctp_cookie alignment to 64 bits */
+ struct sctp_cookie c;
+} __packed;
+
+/* 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_paramhdr p;
+ 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_adaptation_ind_param *aind;
+ struct sctp_supported_ext_param *ext;
+ struct sctp_random_param *random;
+ struct sctp_chunks_param *chunks;
+ struct sctp_hmac_algo_param *hmac_algo;
+ struct sctp_addip_param *addip;
+};
+
+/* 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;
+ __u64 hb_nonce;
+} __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;
+};
+
+struct sctp_ssnmap *sctp_ssnmap_new(__u16 in, __u16 out,
+ gfp_t 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 (*setsockopt) (struct sock *sk,
+ int level,
+ int optname,
+ char __user *optval,
+ unsigned int optlen);
+ int (*getsockopt) (struct sock *sk,
+ int level,
+ int optname,
+ char __user *optval,
+ int __user *optlen);
+ int (*compat_setsockopt) (struct sock *sk,
+ int level,
+ int optname,
+ char __user *optval,
+ unsigned int optlen);
+ int (*compat_getsockopt) (struct sock *sk,
+ int level,
+ int optname,
+ char __user *optval,
+ int __user *optlen);
+ void (*get_dst) (struct sctp_transport *t,
+ union sctp_addr *saddr,
+ struct flowi *fl,
+ struct sock *sk);
+ void (*get_saddr) (struct sctp_sock *sk,
+ struct sctp_transport *t,
+ struct flowi *fl);
+ void (*copy_addrlist) (struct list_head *,
+ struct net_device *);
+ 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 (*from_addr_param) (union sctp_addr *,
+ union sctp_addr_param *,
+ __be16 port, int iif);
+ int (*to_addr_param) (const union sctp_addr *,
+ union sctp_addr_param *);
+ int (*addr_valid) (union sctp_addr *,
+ struct sctp_sock *,
+ const struct sk_buff *);
+ sctp_scope_t (*scope) (union sctp_addr *);
+ void (*inaddr_any) (union sctp_addr *, __be16);
+ 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);
+ void (*ecn_capable)(struct sock *sk);
+ __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 *, __be16 *);
+ struct sock *(*create_accept_sk) (struct sock *sk,
+ struct sctp_association *asoc);
+ int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr);
+ void (*to_sk_saddr)(union sctp_addr *, struct sock *sk);
+ void (*to_sk_daddr)(union sctp_addr *, struct sock *sk);
+ 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;
+ /* 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;
+ u8 send_failed:1,
+ can_abandon:1, /* can chunks from this message can be abandoned. */
+ can_delay; /* should this message be Nagle delayed */
+};
+
+struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
+ struct sctp_sndrcvinfo *,
+ struct iov_iter *);
+void sctp_datamsg_free(struct sctp_datamsg *);
+void sctp_datamsg_put(struct sctp_datamsg *);
+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 {
+ struct list_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;
+ struct sctp_authhdr *auth_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;
+
+ /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO
+ * we need save a pointer to the AUTH chunk, since the SCTP-AUTH
+ * spec violates the principle premis that all chunks are processed
+ * in order.
+ */
+ struct sk_buff *auth_chunk;
+
+#define SCTP_CAN_FRTX 0x0
+#define SCTP_NEED_FRTX 0x1
+#define SCTP_DONT_FRTX 0x2
+ __u16 rtt_in_progress:1, /* This chunk used for RTT calc? */
+ resent:1, /* Has this chunk ever been resent. */
+ has_tsn:1, /* Does this chunk have a TSN yet? */
+ has_ssn:1, /* Does this chunk have a SSN yet? */
+ singleton:1, /* Only chunk in the packet? */
+ end_of_packet:1, /* Last chunk in the packet? */
+ ecn_ce_done:1, /* Have we processed the ECN CE bit? */
+ pdiscard:1, /* Discard the whole packet now? */
+ tsn_gap_acked:1, /* Is this chunk acked by a GAP ACK? */
+ data_accepted:1, /* At least 1 chunk accepted */
+ auth:1, /* IN: was auth'ed | OUT: needs auth */
+ has_asconf:1, /* IN: have seen an asconf before */
+ tsn_missing_report:2, /* Data chunk missing counter. */
+ fast_retransmit:2; /* Is this chunk fast retransmitted? */
+};
+
+void sctp_chunk_hold(struct sctp_chunk *);
+void sctp_chunk_put(struct sctp_chunk *);
+int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len,
+ struct iov_iter *from);
+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);
+
+enum {
+ SCTP_ADDR_NEW, /* new address added to assoc/ep */
+ SCTP_ADDR_SRC, /* address can be used as source */
+ SCTP_ADDR_DEL, /* address about to be deleted */
+};
+
+/* This is a structure for holding either an IPv6 or an IPv4 address. */
+struct sctp_sockaddr_entry {
+ struct list_head list;
+ struct rcu_head rcu;
+ union sctp_addr a;
+ __u8 state;
+ __u8 valid;
+};
+
+#define SCTP_ADDRESS_TICK_DELAY 500
+
+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 list_head chunk_list;
+
+ /* 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;
+
+ /* pointer to the auth chunk for this packet */
+ struct sctp_chunk *auth;
+
+ u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */
+ has_sack:1, /* This packet contains a SACK chunk. */
+ has_auth:1, /* This packet contains an AUTH chunk */
+ has_data:1, /* This packet contains at least 1 DATA chunk */
+ ipfragok:1; /* So let ip fragment this packet */
+};
+
+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 *, int);
+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;
+ __u32 dead:1,
+ /* 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.
+ */
+ rto_pending:1,
+
+ /*
+ * hb_sent : a flag that signals that we have a pending
+ * heartbeat.
+ */
+ hb_sent:1,
+
+ /* Is the Path MTU update pending on this tranport */
+ pmtu_pending:1;
+
+ /* Has this transport moved the ctsn since we last sacked */
+ __u32 sack_generation;
+ u32 dst_cookie;
+
+ struct flowi fl;
+
+ /* 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:
+ */
+ /* RTO : The current retransmission timeout value. */
+ unsigned long rto;
+
+ __u32 rtt; /* This is the most recent RTT. */
+
+ /* RTTVAR : The current RTT variation. */
+ __u32 rttvar;
+
+ /* SRTT : The current smoothed round trip time. */
+ __u32 srtt;
+
+ /*
+ * 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;
+
+ __u32 burst_limited; /* Holds old cwnd when max.burst is applied */
+
+ /* Destination */
+ struct dst_entry *dst;
+ /* Source address. */
+ union sctp_addr saddr;
+
+ /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
+ * the destination address every heartbeat interval.
+ */
+ unsigned long hbinterval;
+
+ /* SACK delay timeout */
+ unsigned long sackdelay;
+ __u32 sackfreq;
+
+ /* When was the last time that we heard from this transport? We use
+ * this to pick new active and retran paths.
+ */
+ ktime_t 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;
+
+ /* This is the max_retrans value for the transport and will
+ * be initialized from the assocs value. This can be changed
+ * using the SCTP_SET_PEER_ADDR_PARAMS socket option.
+ */
+ __u16 pathmaxrxt;
+
+ /* This is the partially failed retrans value for the transport
+ * and will be initialized from the assocs value. This can be changed
+ * using the SCTP_PEER_ADDR_THLDS socket option
+ */
+ int pf_retrans;
+ /* PMTU : The current known path MTU. */
+ __u32 pathmtu;
+
+ /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
+ __u32 param_flags;
+
+ /* The number of times INIT has been sent on this transport. */
+ int init_sent_count;
+
+ /* state : The current state of this destination,
+ * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN.
+ */
+ int state;
+
+ /* These are the error stats for this destination. */
+
+ /* Error count : The current error count for this destination. */
+ unsigned short error_count;
+
+ /* 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;
+
+ /* Timer to handle ICMP proto unreachable envets */
+ struct timer_list proto_unreach_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;
+
+ /* 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;
+
+ /* 64-bit random number sent with heartbeat. */
+ __u64 hb_nonce;
+
+ struct rcu_head rcu;
+};
+
+struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *,
+ gfp_t);
+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 *, struct sock *sk);
+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);
+void sctp_transport_burst_limited(struct sctp_transport *);
+void sctp_transport_burst_reset(struct sctp_transport *);
+unsigned long sctp_transport_timeout(struct sctp_transport *);
+void sctp_transport_reset(struct sctp_transport *);
+void sctp_transport_update_pmtu(struct sock *, struct sctp_transport *, u32);
+void sctp_transport_immediate_rtx(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 list_head in_chunk_list;
+ /* 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;
+};
+
+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 *);
+struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *);
+void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t);
+
+/* 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 list_head out_chunk_list;
+
+ unsigned int out_qlen; /* Total length of queued data chunks. */
+
+ /* Error of send failed, may used in SCTP_SEND_FAILED event. */
+ unsigned int error;
+
+ /* These are control chunks we want to send. */
+ struct list_head control_chunk_list;
+
+ /* 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;
+
+ /* Are we doing fast-rtx on this queue */
+ char fast_rtx;
+
+ /* Corked? */
+ char cork;
+};
+
+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_sack(struct sctp_outq *, struct sctp_chunk *);
+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;
+};
+
+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 net *net, struct sctp_bind_addr *dest,
+ const struct sctp_bind_addr *src,
+ sctp_scope_t scope, gfp_t gfp,
+ int flags);
+int sctp_bind_addr_dup(struct sctp_bind_addr *dest,
+ const struct sctp_bind_addr *src,
+ gfp_t gfp);
+int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
+ __u8 addr_state, gfp_t 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 *);
+int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *,
+ struct sctp_sock *, struct sctp_sock *);
+int sctp_bind_addr_state(const struct sctp_bind_addr *bp,
+ const union sctp_addr *addr);
+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,
+ gfp_t gfp);
+int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len,
+ __u16 port, gfp_t gfp);
+
+sctp_scope_t sctp_scope(const union sctp_addr *);
+int sctp_in_scope(struct net *net, const union sctp_addr *addr, const sctp_scope_t scope);
+int sctp_is_any(struct sock *sk, const union sctp_addr *addr);
+int sctp_is_ep_boundall(struct sock *sk);
+
+
+/* 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 hlist_node node;
+ 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.
+ */
+ atomic_t refcnt;
+ bool dead;
+
+ /* 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;
+};
+
+
+/* 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_SECRET_SIZE];
+
+ /* digest: This is a digest of the sctp cookie. This field is
+ * only used on the receive path when we try to validate
+ * that the cookie has not been tampered with. We put
+ * this here so we pre-allocate this once and can re-use
+ * on every receive.
+ */
+ __u8 *digest;
+
+ /* sendbuf acct. policy. */
+ __u32 sndbuf_policy;
+
+ /* rcvbuf acct. policy. */
+ __u32 rcvbuf_policy;
+
+ /* SCTP AUTH: array of the HMACs that will be allocated
+ * we need this per association so that we don't serialize
+ */
+ struct crypto_hash **auth_hmacs;
+
+ /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */
+ struct sctp_hmac_algo_param *auth_hmacs_list;
+
+ /* SCTP-AUTH: chunks to authenticate encoded into parameter */
+ struct sctp_chunks_param *auth_chunk_list;
+
+ /* SCTP-AUTH: endpoint shared keys */
+ struct list_head endpoint_shared_keys;
+ __u16 active_key_id;
+ __u8 auth_enable;
+};
+
+/* 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 *, gfp_t);
+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 *,
+ struct net *, const union sctp_addr *);
+int sctp_has_association(struct net *net, const union sctp_addr *laddr,
+ const union sctp_addr *paddr);
+
+int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep,
+ 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 *, struct sctp_chunk *chunk,
+ const union sctp_addr *peer,
+ sctp_init_chunk_t *init, gfp_t gfp);
+__u32 sctp_generate_tag(const struct sctp_endpoint *);
+__u32 sctp_generate_tsn(const struct sctp_endpoint *);
+
+struct sctp_inithdr_host {
+ __u32 init_tag;
+ __u32 a_rwnd;
+ __u16 num_outbound_streams;
+ __u16 num_inbound_streams;
+ __u32 initial_tsn;
+};
+
+/* SCTP_GET_ASSOC_STATS counters */
+struct sctp_priv_assoc_stats {
+ /* Maximum observed rto in the association during subsequent
+ * observations. Value is set to 0 if no RTO measurement took place
+ * The transport where the max_rto was observed is returned in
+ * obs_rto_ipaddr
+ */
+ struct sockaddr_storage obs_rto_ipaddr;
+ __u64 max_obs_rto;
+ /* Total In and Out SACKs received and sent */
+ __u64 isacks;
+ __u64 osacks;
+ /* Total In and Out packets received and sent */
+ __u64 opackets;
+ __u64 ipackets;
+ /* Total retransmitted chunks */
+ __u64 rtxchunks;
+ /* TSN received > next expected */
+ __u64 outofseqtsns;
+ /* Duplicate Chunks received */
+ __u64 idupchunks;
+ /* Gap Ack Blocks received */
+ __u64 gapcnt;
+ /* Unordered data chunks sent and received */
+ __u64 ouodchunks;
+ __u64 iuodchunks;
+ /* Ordered data chunks sent and received */
+ __u64 oodchunks;
+ __u64 iodchunks;
+ /* Control chunks sent and received */
+ __u64 octrlchunks;
+ __u64 ictrlchunks;
+};
+
+/* 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 {
+ /* 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.
+ * : The list is also initialized with the list
+ * : of addresses passed with the sctp_connectx()
+ * : call.
+ *
+ * It is a list of SCTP_transport's.
+ */
+ struct list_head transport_addr_list;
+
+ /* rwnd
+ *
+ * Peer Rwnd : Current calculated value of the peer's rwnd.
+ */
+ __u32 rwnd;
+
+ /* transport_count
+ *
+ * Peer : A count of the number of peer addresses
+ * Transport : in the Peer Transport Address List.
+ * Address :
+ * Count :
+ */
+ __u16 transport_count;
+
+ /* 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;
+
+ /* This mask is used to disable sending the ASCONF chunk
+ * with specified parameter to peer.
+ */
+ __be16 addip_disabled_mask;
+
+ /* These are capabilities which our peer advertised. */
+ __u8 ecn_capable:1, /* Can peer do ECN? */
+ ipv4_address:1, /* Peer understands IPv4 addresses? */
+ ipv6_address:1, /* Peer understands IPv6 addresses? */
+ hostname_address:1, /* Peer understands DNS addresses? */
+ asconf_capable:1, /* Does peer support ADDIP? */
+ prsctp_capable:1, /* Can peer do PR-SCTP? */
+ auth_capable:1; /* Is peer doing SCTP-AUTH? */
+
+ /* 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? */
+ __u32 sack_cnt;
+ __u32 sack_generation;
+
+ __u32 adaptation_ind; /* Adaptation Code point. */
+
+ struct sctp_inithdr_host i;
+ void *cookie;
+ int cookie_len;
+
+ /* 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;
+
+ /* SCTP-AUTH: We need to know pears random number, hmac list
+ * and authenticated chunk list. All that is part of the
+ * cookie and these are just pointers to those locations
+ */
+ sctp_random_param_t *peer_random;
+ sctp_chunks_param_t *peer_chunks;
+ sctp_hmac_algo_param_t *peer_hmacs;
+ } 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;
+
+ /* Overall : The overall association error count.
+ * Error Count : [Clear this any time I get something.]
+ */
+ int overall_error_count;
+
+ /* The cookie life I award for any cookie. */
+ ktime_t cookie_life;
+
+ /* 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.
+ */
+ unsigned long rto_initial;
+ unsigned long rto_max;
+ unsigned long 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;
+
+ /* This is the partially failed retrans value for the transport
+ * and will be initialized from the assocs value. This can be
+ * changed using the SCTP_PEER_ADDR_THLDS socket option
+ */
+ int pf_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 */
+ unsigned long max_init_timeo;
+
+ /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
+ * the destination address every heartbeat interval. This value
+ * will be inherited by all new transports.
+ */
+ unsigned long hbinterval;
+
+ /* This is the max_retrans value for new transports in the
+ * association.
+ */
+ __u16 pathmaxrxt;
+
+ /* Flag that path mtu update is pending */
+ __u8 pmtu_pending;
+
+ /* Association : The smallest PMTU discovered for all of the
+ * PMTU : peer's transport addresses.
+ */
+ __u32 pathmtu;
+
+ /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
+ __u32 param_flags;
+
+ __u32 sackfreq;
+ /* SACK delay timeout */
+ unsigned long sackdelay;
+
+ unsigned long 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;
+
+ /* Transport to which INIT chunk was last sent. */
+ struct sctp_transport *init_last_sent_to;
+
+ /* How many times have we resent a SHUTDOWN */
+ int shutdown_retries;
+
+ /* 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;
+
+ /* TSN marking the fast recovery exit point */
+ __u32 fast_recovery_exit;
+
+ /* Flag to track the current fast recovery state */
+ __u8 fast_recovery;
+
+ /* The number of unacknowledged data chunks. Reported through
+ * the SCTP_STATUS sockopt.
+ */
+ __u16 unack_data;
+
+ /* The total number of data chunks that we've had to retransmit
+ * as the result of a T3 timer expiration
+ */
+ __u32 rtx_data_chunks;
+
+ /* 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;
+
+ /* Keeps treack of rwnd pressure. This happens when we have
+ * a window, but not recevie buffer (i.e small packets). This one
+ * is releases slowly (1 PMTU at a time ).
+ */
+ __u32 rwnd_press;
+
+ /* 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 amount of memory that this association has allocated
+ * in the receive path at any given time.
+ */
+ atomic_t rmem_alloc;
+
+ /* This is the wait queue head for send requests waiting on
+ * the association sndbuf space.
+ */
+ wait_queue_head_t wait;
+
+ /* The message size at which SCTP fragmentation will occur. */
+ __u32 frag_point;
+ __u32 user_frag;
+
+ /* Counter used to count INIT errors. */
+ int init_err_counter;
+
+ /* Count the number of INIT cycles (for doubling timeout). */
+ int init_cycle;
+
+ /* Default send parameters. */
+ __u16 default_stream;
+ __u16 default_flags;
+ __u32 default_ppid;
+ __u32 default_context;
+ __u32 default_timetolive;
+
+ /* Default receive parameters */
+ __u32 default_rcv_context;
+
+ /* 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;
+
+ /* 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 5.2 Upon reception of an ASCONF Chunk.
+ *
+ * This is needed to implement itmes E1 - E4 of the updated
+ * spec. Here is the justification:
+ *
+ * Since the peer may bundle multiple ASCONF chunks toward us,
+ * we now need the ability to cache multiple ACKs. The section
+ * describes in detail how they are cached and cleaned up.
+ */
+ struct list_head asconf_ack_list;
+
+ /* 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 list_head addip_chunk_list;
+
+ /* 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;
+ int src_out_of_asoc_ok;
+ union sctp_addr *asconf_addr_del_pending;
+ struct sctp_transport *new_transport;
+
+ /* SCTP AUTH: list of the endpoint shared keys. These
+ * keys are provided out of band by the user applicaton
+ * and can't change during the lifetime of the association
+ */
+ struct list_head endpoint_shared_keys;
+
+ /* SCTP AUTH:
+ * The current generated assocaition shared key (secret)
+ */
+ struct sctp_auth_bytes *asoc_shared_key;
+
+ /* SCTP AUTH: hmac id of the first peer requested algorithm
+ * that we support.
+ */
+ __u16 default_hmac_id;
+
+ __u16 active_key_id;
+
+ __u8 need_ecne:1, /* Need to send an ECNE Chunk? */
+ temp:1; /* Is it a temporary association? */
+
+ struct sctp_priv_assoc_stats stats;
+};
+
+
+/* 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, gfp_t 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_alter_transport(
+ struct sctp_association *, struct sctp_transport *);
+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 gfp_t gfp,
+ const int peer_state);
+void sctp_assoc_del_peer(struct sctp_association *asoc,
+ const union sctp_addr *addr);
+void sctp_assoc_rm_peer(struct sctp_association *asoc,
+ struct sctp_transport *peer);
+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 *,
+ struct net *,
+ 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 sock *, struct sctp_association *);
+void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int);
+void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int);
+void sctp_assoc_set_primary(struct sctp_association *,
+ struct sctp_transport *);
+void sctp_assoc_del_nonprimary_peers(struct sctp_association *,
+ struct sctp_transport *);
+int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *,
+ sctp_scope_t, gfp_t);
+int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
+ struct sctp_cookie*,
+ gfp_t gfp);
+int sctp_assoc_set_id(struct sctp_association *, gfp_t);
+void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc);
+struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
+ const struct sctp_association *asoc,
+ __be32 serial);
+void sctp_asconf_queue_teardown(struct sctp_association *asoc);
+
+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 *srinfo;
+ struct sctp_sndinfo *sinfo;
+} sctp_cmsgs_t;
+
+/* Structure for tracking memory objects */
+typedef struct {
+ char *label;
+ atomic_t *counter;
+} sctp_dbg_objcnt_entry_t;
+
+#endif /* __sctp_structs_h__ */
Code Review / kvmfornfv.git / blobdiff