/* SPDX-License-Identifier: GPL-2.0-or-later */ /* SCTP kernel implementation * (C) Copyright IBM Corp. 2001, 2004 * Copyright (c) 1999-2000 Cisco, Inc. * Copyright (c) 1999-2001 Motorola, Inc. * Copyright (c) 2001-2003 Intel Corp. * * This file is part of the SCTP kernel implementation * * The base lksctp header. * * Please send any bug reports or fixes you make to the * email address(es): * lksctp developers * * Written or modified by: * La Monte H.P. Yarroll * Xingang Guo * Jon Grimm * Daisy Chang * Sridhar Samudrala * Ardelle Fan * Ryan Layer * Kevin Gao */ #ifndef __net_sctp_h__ #define __net_sctp_h__ /* Header Strategy. * Start getting some control over the header file dependencies: * includes * constants * structs * prototypes * macros, externs, and inlines * * Move test_frame specific items out of the kernel headers * and into the test frame headers. This is not perfect in any sense * and will continue to evolve. */ #include #include #include #include #include #include #include #include #if IS_ENABLED(CONFIG_IPV6) #include #include #endif #include #include #include #include #include #include #ifdef CONFIG_IP_SCTP_MODULE #define SCTP_PROTOSW_FLAG 0 #else /* static! */ #define SCTP_PROTOSW_FLAG INET_PROTOSW_PERMANENT #endif /* * Function declarations. */ /* * sctp/protocol.c */ int sctp_copy_local_addr_list(struct net *net, struct sctp_bind_addr *addr, enum sctp_scope, gfp_t gfp, int flags); struct sctp_pf *sctp_get_pf_specific(sa_family_t family); int sctp_register_pf(struct sctp_pf *, sa_family_t); void sctp_addr_wq_mgmt(struct net *, struct sctp_sockaddr_entry *, int); int sctp_udp_sock_start(struct net *net); void sctp_udp_sock_stop(struct net *net); /* * sctp/socket.c */ int sctp_inet_connect(struct socket *sock, struct sockaddr *uaddr, int addr_len, int flags); int sctp_backlog_rcv(struct sock *sk, struct sk_buff *skb); int sctp_inet_listen(struct socket *sock, int backlog); void sctp_write_space(struct sock *sk); void sctp_data_ready(struct sock *sk); __poll_t sctp_poll(struct file *file, struct socket *sock, poll_table *wait); void sctp_sock_rfree(struct sk_buff *skb); void sctp_copy_sock(struct sock *newsk, struct sock *sk, struct sctp_association *asoc); extern struct percpu_counter sctp_sockets_allocated; int sctp_asconf_mgmt(struct sctp_sock *, struct sctp_sockaddr_entry *); struct sk_buff *sctp_skb_recv_datagram(struct sock *, int, int *); typedef int (*sctp_callback_t)(struct sctp_endpoint *, struct sctp_transport *, void *); void sctp_transport_walk_start(struct rhashtable_iter *iter); void sctp_transport_walk_stop(struct rhashtable_iter *iter); struct sctp_transport *sctp_transport_get_next(struct net *net, struct rhashtable_iter *iter); struct sctp_transport *sctp_transport_get_idx(struct net *net, struct rhashtable_iter *iter, int pos); int sctp_transport_lookup_process(sctp_callback_t cb, struct net *net, const union sctp_addr *laddr, const union sctp_addr *paddr, void *p, int dif); int sctp_transport_traverse_process(sctp_callback_t cb, sctp_callback_t cb_done, struct net *net, int *pos, void *p); int sctp_for_each_endpoint(int (*cb)(struct sctp_endpoint *, void *), void *p); int sctp_get_sctp_info(struct sock *sk, struct sctp_association *asoc, struct sctp_info *info); /* * sctp/primitive.c */ int sctp_primitive_ASSOCIATE(struct net *, struct sctp_association *, void *arg); int sctp_primitive_SHUTDOWN(struct net *, struct sctp_association *, void *arg); int sctp_primitive_ABORT(struct net *, struct sctp_association *, void *arg); int sctp_primitive_SEND(struct net *, struct sctp_association *, void *arg); int sctp_primitive_REQUESTHEARTBEAT(struct net *, struct sctp_association *, void *arg); int sctp_primitive_ASCONF(struct net *, struct sctp_association *, void *arg); int sctp_primitive_RECONF(struct net *net, struct sctp_association *asoc, void *arg); /* * sctp/input.c */ int sctp_rcv(struct sk_buff *skb); int sctp_v4_err(struct sk_buff *skb, u32 info); int sctp_hash_endpoint(struct sctp_endpoint *ep); void sctp_unhash_endpoint(struct sctp_endpoint *); struct sock *sctp_err_lookup(struct net *net, int family, struct sk_buff *, struct sctphdr *, struct sctp_association **, struct sctp_transport **); void sctp_err_finish(struct sock *, struct sctp_transport *); int sctp_udp_v4_err(struct sock *sk, struct sk_buff *skb); int sctp_udp_v6_err(struct sock *sk, struct sk_buff *skb); void sctp_icmp_frag_needed(struct sock *, struct sctp_association *, struct sctp_transport *t, __u32 pmtu); void sctp_icmp_redirect(struct sock *, struct sctp_transport *, struct sk_buff *); void sctp_icmp_proto_unreachable(struct sock *sk, struct sctp_association *asoc, struct sctp_transport *t); int sctp_transport_hashtable_init(void); void sctp_transport_hashtable_destroy(void); int sctp_hash_transport(struct sctp_transport *t); void sctp_unhash_transport(struct sctp_transport *t); struct sctp_transport *sctp_addrs_lookup_transport( struct net *net, const union sctp_addr *laddr, const union sctp_addr *paddr, int dif, int sdif); struct sctp_transport *sctp_epaddr_lookup_transport( const struct sctp_endpoint *ep, const union sctp_addr *paddr); bool sctp_sk_bound_dev_eq(struct net *net, int bound_dev_if, int dif, int sdif); /* * sctp/proc.c */ int __net_init sctp_proc_init(struct net *net); /* * sctp/offload.c */ int sctp_offload_init(void); /* * sctp/stream_sched.c */ void sctp_sched_ops_init(void); /* * sctp/stream.c */ int sctp_send_reset_streams(struct sctp_association *asoc, struct sctp_reset_streams *params); int sctp_send_reset_assoc(struct sctp_association *asoc); int sctp_send_add_streams(struct sctp_association *asoc, struct sctp_add_streams *params); /* * Module global variables */ /* * sctp/protocol.c */ extern struct kmem_cache *sctp_chunk_cachep __read_mostly; extern struct kmem_cache *sctp_bucket_cachep __read_mostly; extern long sysctl_sctp_mem[3]; extern int sysctl_sctp_rmem[3]; extern int sysctl_sctp_wmem[3]; /* * Section: Macros, externs, and inlines */ /* SCTP SNMP MIB stats handlers */ #define SCTP_INC_STATS(net, field) SNMP_INC_STATS((net)->sctp.sctp_statistics, field) #define __SCTP_INC_STATS(net, field) __SNMP_INC_STATS((net)->sctp.sctp_statistics, field) #define SCTP_DEC_STATS(net, field) SNMP_DEC_STATS((net)->sctp.sctp_statistics, field) /* sctp mib definitions */ enum { SCTP_MIB_NUM = 0, SCTP_MIB_CURRESTAB, /* CurrEstab */ SCTP_MIB_ACTIVEESTABS, /* ActiveEstabs */ SCTP_MIB_PASSIVEESTABS, /* PassiveEstabs */ SCTP_MIB_ABORTEDS, /* Aborteds */ SCTP_MIB_SHUTDOWNS, /* Shutdowns */ SCTP_MIB_OUTOFBLUES, /* OutOfBlues */ SCTP_MIB_CHECKSUMERRORS, /* ChecksumErrors */ SCTP_MIB_OUTCTRLCHUNKS, /* OutCtrlChunks */ SCTP_MIB_OUTORDERCHUNKS, /* OutOrderChunks */ SCTP_MIB_OUTUNORDERCHUNKS, /* OutUnorderChunks */ SCTP_MIB_INCTRLCHUNKS, /* InCtrlChunks */ SCTP_MIB_INORDERCHUNKS, /* InOrderChunks */ SCTP_MIB_INUNORDERCHUNKS, /* InUnorderChunks */ SCTP_MIB_FRAGUSRMSGS, /* FragUsrMsgs */ SCTP_MIB_REASMUSRMSGS, /* ReasmUsrMsgs */ SCTP_MIB_OUTSCTPPACKS, /* OutSCTPPacks */ SCTP_MIB_INSCTPPACKS, /* InSCTPPacks */ SCTP_MIB_T1_INIT_EXPIREDS, SCTP_MIB_T1_COOKIE_EXPIREDS, SCTP_MIB_T2_SHUTDOWN_EXPIREDS, SCTP_MIB_T3_RTX_EXPIREDS, SCTP_MIB_T4_RTO_EXPIREDS, SCTP_MIB_T5_SHUTDOWN_GUARD_EXPIREDS, SCTP_MIB_DELAY_SACK_EXPIREDS, SCTP_MIB_AUTOCLOSE_EXPIREDS, SCTP_MIB_T1_RETRANSMITS, SCTP_MIB_T3_RETRANSMITS, SCTP_MIB_PMTUD_RETRANSMITS, SCTP_MIB_FAST_RETRANSMITS, SCTP_MIB_IN_PKT_SOFTIRQ, SCTP_MIB_IN_PKT_BACKLOG, SCTP_MIB_IN_PKT_DISCARDS, SCTP_MIB_IN_DATA_CHUNK_DISCARDS, __SCTP_MIB_MAX }; #define SCTP_MIB_MAX __SCTP_MIB_MAX struct sctp_mib { unsigned long mibs[SCTP_MIB_MAX]; }; /* helper function to track stats about max rto and related transport */ static inline void sctp_max_rto(struct sctp_association *asoc, struct sctp_transport *trans) { if (asoc->stats.max_obs_rto < (__u64)trans->rto) { asoc->stats.max_obs_rto = trans->rto; memset(&asoc->stats.obs_rto_ipaddr, 0, sizeof(struct sockaddr_storage)); memcpy(&asoc->stats.obs_rto_ipaddr, &trans->ipaddr, trans->af_specific->sockaddr_len); } } /* * Macros for keeping a global reference of object allocations. */ #ifdef CONFIG_SCTP_DBG_OBJCNT extern atomic_t sctp_dbg_objcnt_sock; extern atomic_t sctp_dbg_objcnt_ep; extern atomic_t sctp_dbg_objcnt_assoc; extern atomic_t sctp_dbg_objcnt_transport; extern atomic_t sctp_dbg_objcnt_chunk; extern atomic_t sctp_dbg_objcnt_bind_addr; extern atomic_t sctp_dbg_objcnt_bind_bucket; extern atomic_t sctp_dbg_objcnt_addr; extern atomic_t sctp_dbg_objcnt_datamsg; extern atomic_t sctp_dbg_objcnt_keys; /* Macros to atomically increment/decrement objcnt counters. */ #define SCTP_DBG_OBJCNT_INC(name) \ atomic_inc(&sctp_dbg_objcnt_## name) #define SCTP_DBG_OBJCNT_DEC(name) \ atomic_dec(&sctp_dbg_objcnt_## name) #define SCTP_DBG_OBJCNT(name) \ atomic_t sctp_dbg_objcnt_## name = ATOMIC_INIT(0) /* Macro to help create new entries in the global array of * objcnt counters. */ #define SCTP_DBG_OBJCNT_ENTRY(name) \ {.label= #name, .counter= &sctp_dbg_objcnt_## name} void sctp_dbg_objcnt_init(struct net *); #else #define SCTP_DBG_OBJCNT_INC(name) #define SCTP_DBG_OBJCNT_DEC(name) static inline void sctp_dbg_objcnt_init(struct net *net) { return; } #endif /* CONFIG_SCTP_DBG_OBJCOUNT */ #if defined CONFIG_SYSCTL void sctp_sysctl_register(void); void sctp_sysctl_unregister(void); int sctp_sysctl_net_register(struct net *net); void sctp_sysctl_net_unregister(struct net *net); #else static inline void sctp_sysctl_register(void) { return; } static inline void sctp_sysctl_unregister(void) { return; } static inline int sctp_sysctl_net_register(struct net *net) { return 0; } static inline void sctp_sysctl_net_unregister(struct net *net) { return; } #endif /* Size of Supported Address Parameter for 'x' address types. */ #define SCTP_SAT_LEN(x) (sizeof(struct sctp_paramhdr) + (x) * sizeof(__u16)) #if IS_ENABLED(CONFIG_IPV6) void sctp_v6_pf_init(void); void sctp_v6_pf_exit(void); int sctp_v6_protosw_init(void); void sctp_v6_protosw_exit(void); int sctp_v6_add_protocol(void); void sctp_v6_del_protocol(void); #else /* #ifdef defined(CONFIG_IPV6) */ static inline void sctp_v6_pf_init(void) { return; } static inline void sctp_v6_pf_exit(void) { return; } static inline int sctp_v6_protosw_init(void) { return 0; } static inline void sctp_v6_protosw_exit(void) { return; } static inline int sctp_v6_add_protocol(void) { return 0; } static inline void sctp_v6_del_protocol(void) { return; } #endif /* #if defined(CONFIG_IPV6) */ /* Map an association to an assoc_id. */ static inline sctp_assoc_t sctp_assoc2id(const struct sctp_association *asoc) { return asoc ? asoc->assoc_id : 0; } static inline enum sctp_sstat_state sctp_assoc_to_state(const struct sctp_association *asoc) { /* SCTP's uapi always had SCTP_EMPTY(=0) as a dummy state, but we * got rid of it in kernel space. Therefore SCTP_CLOSED et al * start at =1 in user space, but actually as =0 in kernel space. * Now that we can not break user space and SCTP_EMPTY is exposed * there, we need to fix it up with an ugly offset not to break * applications. :( */ return asoc->state + 1; } /* Look up the association by its id. */ struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id); int sctp_do_peeloff(struct sock *sk, sctp_assoc_t id, struct socket **sockp); /* A macro to walk a list of skbs. */ #define sctp_skb_for_each(pos, head, tmp) \ skb_queue_walk_safe(head, pos, tmp) /** * sctp_list_dequeue - remove from the head of the queue * @list: list to dequeue from * * Remove the head of the list. The head item is * returned or %NULL if the list is empty. */ static inline struct list_head *sctp_list_dequeue(struct list_head *list) { struct list_head *result = NULL; if (!list_empty(list)) { result = list->next; list_del_init(result); } return result; } /* SCTP version of skb_set_owner_r. We need this one because * of the way we have to do receive buffer accounting on bundled * chunks. */ static inline void sctp_skb_set_owner_r(struct sk_buff *skb, struct sock *sk) { struct sctp_ulpevent *event = sctp_skb2event(skb); skb_orphan(skb); skb->sk = sk; skb->destructor = sctp_sock_rfree; atomic_add(event->rmem_len, &sk->sk_rmem_alloc); /* * This mimics the behavior of skb_set_owner_r */ sk_mem_charge(sk, event->rmem_len); } /* Tests if the list has one and only one entry. */ static inline int sctp_list_single_entry(struct list_head *head) { return list_is_singular(head); } static inline bool sctp_chunk_pending(const struct sctp_chunk *chunk) { return !list_empty(&chunk->list); } /* Walk through a list of TLV parameters. Don't trust the * individual parameter lengths and instead depend on * the chunk length to indicate when to stop. Make sure * there is room for a param header too. */ #define sctp_walk_params(pos, chunk)\ _sctp_walk_params((pos), (chunk), ntohs((chunk)->chunk_hdr.length)) #define _sctp_walk_params(pos, chunk, end)\ for (pos.v = (u8 *)(chunk + 1);\ (pos.v + offsetof(struct sctp_paramhdr, length) + sizeof(pos.p->length) <=\ (void *)chunk + end) &&\ pos.v <= (void *)chunk + end - ntohs(pos.p->length) &&\ ntohs(pos.p->length) >= sizeof(struct sctp_paramhdr);\ pos.v += SCTP_PAD4(ntohs(pos.p->length))) #define sctp_walk_errors(err, chunk_hdr)\ _sctp_walk_errors((err), (chunk_hdr), ntohs((chunk_hdr)->length)) #define _sctp_walk_errors(err, chunk_hdr, end)\ for (err = (struct sctp_errhdr *)((void *)chunk_hdr + \ sizeof(struct sctp_chunkhdr));\ ((void *)err + offsetof(struct sctp_errhdr, length) + sizeof(err->length) <=\ (void *)chunk_hdr + end) &&\ (void *)err <= (void *)chunk_hdr + end - ntohs(err->length) &&\ ntohs(err->length) >= sizeof(struct sctp_errhdr); \ err = (struct sctp_errhdr *)((void *)err + SCTP_PAD4(ntohs(err->length)))) #define sctp_walk_fwdtsn(pos, chunk)\ _sctp_walk_fwdtsn((pos), (chunk), ntohs((chunk)->chunk_hdr->length) - sizeof(struct sctp_fwdtsn_chunk)) #define _sctp_walk_fwdtsn(pos, chunk, end)\ for (pos = (void *)(chunk->subh.fwdtsn_hdr + 1);\ (void *)pos <= (void *)(chunk->subh.fwdtsn_hdr + 1) + end - sizeof(struct sctp_fwdtsn_skip);\ pos++) /* External references. */ extern struct proto sctp_prot; extern struct proto sctpv6_prot; void sctp_put_port(struct sock *sk); extern struct idr sctp_assocs_id; extern spinlock_t sctp_assocs_id_lock; /* Static inline functions. */ /* Convert from an IP version number to an Address Family symbol. */ static inline int ipver2af(__u8 ipver) { switch (ipver) { case 4: return AF_INET; case 6: return AF_INET6; default: return 0; } } /* Convert from an address parameter type to an address family. */ static inline int param_type2af(__be16 type) { switch (type) { case SCTP_PARAM_IPV4_ADDRESS: return AF_INET; case SCTP_PARAM_IPV6_ADDRESS: return AF_INET6; default: return 0; } } /* Warning: The following hash functions assume a power of two 'size'. */ /* This is the hash function for the SCTP port hash table. */ static inline int sctp_phashfn(struct net *net, __u16 lport) { return (net_hash_mix(net) + lport) & (sctp_port_hashsize - 1); } /* This is the hash function for the endpoint hash table. */ static inline int sctp_ep_hashfn(struct net *net, __u16 lport) { return (net_hash_mix(net) + lport) & (sctp_ep_hashsize - 1); } #define sctp_for_each_hentry(ep, head) \ hlist_for_each_entry(ep, head, node) /* Is a socket of this style? */ #define sctp_style(sk, style) __sctp_style((sk), (SCTP_SOCKET_##style)) static inline int __sctp_style(const struct sock *sk, enum sctp_socket_type style) { return sctp_sk(sk)->type == style; } /* Is the association in this state? */ #define sctp_state(asoc, state) __sctp_state((asoc), (SCTP_STATE_##state)) static inline int __sctp_state(const struct sctp_association *asoc, enum sctp_state state) { return asoc->state == state; } /* Is the socket in this state? */ #define sctp_sstate(sk, state) __sctp_sstate((sk), (SCTP_SS_##state)) static inline int __sctp_sstate(const struct sock *sk, enum sctp_sock_state state) { return sk->sk_state == state; } /* Map v4-mapped v6 address back to v4 address */ static inline void sctp_v6_map_v4(union sctp_addr *addr) { addr->v4.sin_family = AF_INET; addr->v4.sin_port = addr->v6.sin6_port; addr->v4.sin_addr.s_addr = addr->v6.sin6_addr.s6_addr32[3]; } /* Map v4 address to v4-mapped v6 address */ static inline void sctp_v4_map_v6(union sctp_addr *addr) { __be16 port; port = addr->v4.sin_port; addr->v6.sin6_addr.s6_addr32[3] = addr->v4.sin_addr.s_addr; addr->v6.sin6_port = port; addr->v6.sin6_family = AF_INET6; addr->v6.sin6_flowinfo = 0; addr->v6.sin6_scope_id = 0; addr->v6.sin6_addr.s6_addr32[0] = 0; addr->v6.sin6_addr.s6_addr32[1] = 0; addr->v6.sin6_addr.s6_addr32[2] = htonl(0x0000ffff); } /* The cookie is always 0 since this is how it's used in the * pmtu code. */ static inline struct dst_entry *sctp_transport_dst_check(struct sctp_transport *t) { if (t->dst && !dst_check(t->dst, t->dst_cookie)) sctp_transport_dst_release(t); return t->dst; } /* Calculate max payload size given a MTU, or the total overhead if * given MTU is zero */ static inline __u32 __sctp_mtu_payload(const struct sctp_sock *sp, const struct sctp_transport *t, __u32 mtu, __u32 extra) { __u32 overhead = sizeof(struct sctphdr) + extra; if (sp) { overhead += sp->pf->af->net_header_len; if (sp->udp_port && (!t || t->encap_port)) overhead += sizeof(struct udphdr); } else { overhead += sizeof(struct ipv6hdr); } if (WARN_ON_ONCE(mtu && mtu <= overhead)) mtu = overhead; return mtu ? mtu - overhead : overhead; } static inline __u32 sctp_mtu_payload(const struct sctp_sock *sp, __u32 mtu, __u32 extra) { return __sctp_mtu_payload(sp, NULL, mtu, extra); } static inline __u32 sctp_dst_mtu(const struct dst_entry *dst) { return SCTP_TRUNC4(max_t(__u32, dst_mtu(dst), SCTP_DEFAULT_MINSEGMENT)); } static inline bool sctp_transport_pmtu_check(struct sctp_transport *t) { __u32 pmtu = sctp_dst_mtu(t->dst); if (t->pathmtu == pmtu) return true; t->pathmtu = pmtu; return false; } static inline __u32 sctp_min_frag_point(struct sctp_sock *sp, __u16 datasize) { return sctp_mtu_payload(sp, SCTP_DEFAULT_MINSEGMENT, datasize); } static inline int sctp_transport_pl_hlen(struct sctp_transport *t) { return __sctp_mtu_payload(sctp_sk(t->asoc->base.sk), t, 0, 0) - sizeof(struct sctphdr); } static inline void sctp_transport_pl_reset(struct sctp_transport *t) { if (t->probe_interval && (t->param_flags & SPP_PMTUD_ENABLE) && (t->state == SCTP_ACTIVE || t->state == SCTP_UNKNOWN)) { if (t->pl.state == SCTP_PL_DISABLED) { t->pl.state = SCTP_PL_BASE; t->pl.pmtu = SCTP_BASE_PLPMTU; t->pl.probe_size = SCTP_BASE_PLPMTU; sctp_transport_reset_probe_timer(t); } } else { if (t->pl.state != SCTP_PL_DISABLED) { if (del_timer(&t->probe_timer)) sctp_transport_put(t); t->pl.state = SCTP_PL_DISABLED; } } } static inline void sctp_transport_pl_update(struct sctp_transport *t) { if (t->pl.state == SCTP_PL_DISABLED) return; t->pl.state = SCTP_PL_BASE; t->pl.pmtu = SCTP_BASE_PLPMTU; t->pl.probe_size = SCTP_BASE_PLPMTU; sctp_transport_reset_probe_timer(t); } static inline bool sctp_transport_pl_enabled(struct sctp_transport *t) { return t->pl.state != SCTP_PL_DISABLED; } static inline bool sctp_newsk_ready(const struct sock *sk) { return sock_flag(sk, SOCK_DEAD) || sk->sk_socket; } static inline void sctp_sock_set_nodelay(struct sock *sk) { lock_sock(sk); sctp_sk(sk)->nodelay = true; release_sock(sk); } #endif /* __net_sctp_h__ */