/* 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. * Copyright (c) 2001-2002 Nokia, Inc. * Copyright (c) 2001 La Monte H.P. Yarroll * * This file is part of the SCTP kernel implementation * * These functions interface with the sockets layer to implement the * SCTP Extensions for the Sockets API. * * Note that the descriptions from the specification are USER level * functions--this file is the functions which populate the struct proto * for SCTP which is the BOTTOM of the sockets interface. * * 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, 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 address(es): * lksctp developers * * Or submit a bug report through the following website: * http://www.sf.net/projects/lksctp * * Written or modified by: * La Monte H.P. Yarroll * Narasimha Budihal * Karl Knutson * Jon Grimm * Xingang Guo * Daisy Chang * Sridhar Samudrala * Inaky Perez-Gonzalez * Ardelle Fan * Ryan Layer * Anup Pemmaiah * Kevin Gao * * Any bugs reported given to us we will try to fix... any fixes shared will * be incorporated into the next SCTP release. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* for sa_family_t */ #include #include #include #include /* WARNING: Please do not remove the SCTP_STATIC attribute to * any of the functions below as they are used to export functions * used by a project regression testsuite. */ /* Forward declarations for internal helper functions. */ static int sctp_writeable(struct sock *sk); static void sctp_wfree(struct sk_buff *skb); static int sctp_wait_for_sndbuf(struct sctp_association *, long *timeo_p, size_t msg_len); static int sctp_wait_for_packet(struct sock * sk, int *err, long *timeo_p); static int sctp_wait_for_connect(struct sctp_association *, long *timeo_p); static int sctp_wait_for_accept(struct sock *sk, long timeo); static void sctp_wait_for_close(struct sock *sk, long timeo); static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt, union sctp_addr *addr, int len); static int sctp_bindx_add(struct sock *, struct sockaddr *, int); static int sctp_bindx_rem(struct sock *, struct sockaddr *, int); static int sctp_send_asconf_add_ip(struct sock *, struct sockaddr *, int); static int sctp_send_asconf_del_ip(struct sock *, struct sockaddr *, int); static int sctp_send_asconf(struct sctp_association *asoc, struct sctp_chunk *chunk); static int sctp_do_bind(struct sock *, union sctp_addr *, int); static int sctp_autobind(struct sock *sk); static void sctp_sock_migrate(struct sock *, struct sock *, struct sctp_association *, sctp_socket_type_t); static char *sctp_hmac_alg = SCTP_COOKIE_HMAC_ALG; extern struct kmem_cache *sctp_bucket_cachep; extern long sysctl_sctp_mem[3]; extern int sysctl_sctp_rmem[3]; extern int sysctl_sctp_wmem[3]; static int sctp_memory_pressure; static atomic_long_t sctp_memory_allocated; struct percpu_counter sctp_sockets_allocated; static void sctp_enter_memory_pressure(struct sock *sk) { sctp_memory_pressure = 1; } /* Get the sndbuf space available at the time on the association. */ static inline int sctp_wspace(struct sctp_association *asoc) { int amt; if (asoc->ep->sndbuf_policy) amt = asoc->sndbuf_used; else amt = sk_wmem_alloc_get(asoc->base.sk); if (amt >= asoc->base.sk->sk_sndbuf) { if (asoc->base.sk->sk_userlocks & SOCK_SNDBUF_LOCK) amt = 0; else { amt = sk_stream_wspace(asoc->base.sk); if (amt < 0) amt = 0; } } else { amt = asoc->base.sk->sk_sndbuf - amt; } return amt; } /* Increment the used sndbuf space count of the corresponding association by * the size of the outgoing data chunk. * Also, set the skb destructor for sndbuf accounting later. * * Since it is always 1-1 between chunk and skb, and also a new skb is always * allocated for chunk bundling in sctp_packet_transmit(), we can use the * destructor in the data chunk skb for the purpose of the sndbuf space * tracking. */ static inline void sctp_set_owner_w(struct sctp_chunk *chunk) { struct sctp_association *asoc = chunk->asoc; struct sock *sk = asoc->base.sk; /* The sndbuf space is tracked per association. */ sctp_association_hold(asoc); skb_set_owner_w(chunk->skb, sk); chunk->skb->destructor = sctp_wfree; /* Save the chunk pointer in skb for sctp_wfree to use later. */ *((struct sctp_chunk **)(chunk->skb->cb)) = chunk; asoc->sndbuf_used += SCTP_DATA_SNDSIZE(chunk) + sizeof(struct sk_buff) + sizeof(struct sctp_chunk); atomic_add(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc); sk->sk_wmem_queued += chunk->skb->truesize; sk_mem_charge(sk, chunk->skb->truesize); } /* Verify that this is a valid address. */ static inline int sctp_verify_addr(struct sock *sk, union sctp_addr *addr, int len) { struct sctp_af *af; /* Verify basic sockaddr. */ af = sctp_sockaddr_af(sctp_sk(sk), addr, len); if (!af) return -EINVAL; /* Is this a valid SCTP address? */ if (!af->addr_valid(addr, sctp_sk(sk), NULL)) return -EINVAL; if (!sctp_sk(sk)->pf->send_verify(sctp_sk(sk), (addr))) return -EINVAL; return 0; } /* Look up the association by its id. If this is not a UDP-style * socket, the ID field is always ignored. */ struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id) { struct sctp_association *asoc = NULL; /* If this is not a UDP-style socket, assoc id should be ignored. */ if (!sctp_style(sk, UDP)) { /* Return NULL if the socket state is not ESTABLISHED. It * could be a TCP-style listening socket or a socket which * hasn't yet called connect() to establish an association. */ if (!sctp_sstate(sk, ESTABLISHED)) return NULL; /* Get the first and the only association from the list. */ if (!list_empty(&sctp_sk(sk)->ep->asocs)) asoc = list_entry(sctp_sk(sk)->ep->asocs.next, struct sctp_association, asocs); return asoc; } /* Otherwise this is a UDP-style socket. */ if (!id || (id == (sctp_assoc_t)-1)) return NULL; spin_lock_bh(&sctp_assocs_id_lock); asoc = (struct sctp_association *)idr_find(&sctp_assocs_id, (int)id); spin_unlock_bh(&sctp_assocs_id_lock); if (!asoc || (asoc->base.sk != sk) || asoc->base.dead) return NULL; return asoc; } /* Look up the transport from an address and an assoc id. If both address and * id are specified, the associations matching the address and the id should be * the same. */ static struct sctp_transport *sctp_addr_id2transport(struct sock *sk, struct sockaddr_storage *addr, sctp_assoc_t id) { struct sctp_association *addr_asoc = NULL, *id_asoc = NULL; struct sctp_transport *transport; union sctp_addr *laddr = (union sctp_addr *)addr; addr_asoc = sctp_endpoint_lookup_assoc(sctp_sk(sk)->ep, laddr, &transport); if (!addr_asoc) return NULL; id_asoc = sctp_id2assoc(sk, id); if (id_asoc && (id_asoc != addr_asoc)) return NULL; sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk), (union sctp_addr *)addr); return transport; } /* API 3.1.2 bind() - UDP Style Syntax * The syntax of bind() is, * * ret = bind(int sd, struct sockaddr *addr, int addrlen); * * sd - the socket descriptor returned by socket(). * addr - the address structure (struct sockaddr_in or struct * sockaddr_in6 [RFC 2553]), * addr_len - the size of the address structure. */ SCTP_STATIC int sctp_bind(struct sock *sk, struct sockaddr *addr, int addr_len) { int retval = 0; sctp_lock_sock(sk); SCTP_DEBUG_PRINTK("sctp_bind(sk: %p, addr: %p, addr_len: %d)\n", sk, addr, addr_len); /* Disallow binding twice. */ if (!sctp_sk(sk)->ep->base.bind_addr.port) retval = sctp_do_bind(sk, (union sctp_addr *)addr, addr_len); else retval = -EINVAL; sctp_release_sock(sk); return retval; } static long sctp_get_port_local(struct sock *, union sctp_addr *); /* Verify this is a valid sockaddr. */ static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt, union sctp_addr *addr, int len) { struct sctp_af *af; /* Check minimum size. */ if (len < sizeof (struct sockaddr)) return NULL; /* V4 mapped address are really of AF_INET family */ if (addr->sa.sa_family == AF_INET6 && ipv6_addr_v4mapped(&addr->v6.sin6_addr)) { if (!opt->pf->af_supported(AF_INET, opt)) return NULL; } else { /* Does this PF support this AF? */ if (!opt->pf->af_supported(addr->sa.sa_family, opt)) return NULL; } /* If we get this far, af is valid. */ af = sctp_get_af_specific(addr->sa.sa_family); if (len < af->sockaddr_len) return NULL; return af; } /* Bind a local address either to an endpoint or to an association. */ SCTP_STATIC int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len) { struct sctp_sock *sp = sctp_sk(sk); struct sctp_endpoint *ep = sp->ep; struct sctp_bind_addr *bp = &ep->base.bind_addr; struct sctp_af *af; unsigned short snum; int ret = 0; /* Common sockaddr verification. */ af = sctp_sockaddr_af(sp, addr, len); if (!af) { SCTP_DEBUG_PRINTK("sctp_do_bind(sk: %p, newaddr: %p, len: %d) EINVAL\n", sk, addr, len); return -EINVAL; } snum = ntohs(addr->v4.sin_port); SCTP_DEBUG_PRINTK_IPADDR("sctp_do_bind(sk: %p, new addr: ", ", port: %d, new port: %d, len: %d)\n", sk, addr, bp->port, snum, len); /* PF specific bind() address verification. */ if (!sp->pf->bind_verify(sp, addr)) return -EADDRNOTAVAIL; /* We must either be unbound, or bind to the same port. * It's OK to allow 0 ports if we are already bound. * We'll just inhert an already bound port in this case */ if (bp->port) { if (!snum) snum = bp->port; else if (snum != bp->port) { SCTP_DEBUG_PRINTK("sctp_do_bind:" " New port %d does not match existing port " "%d.\n", snum, bp->port); return -EINVAL; } } if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE)) return -EACCES; /* See if the address matches any of the addresses we may have * already bound before checking against other endpoints. */ if (sctp_bind_addr_match(bp, addr, sp)) return -EINVAL; /* Make sure we are allowed to bind here. * The function sctp_get_port_local() does duplicate address * detection. */ addr->v4.sin_port = htons(snum); if ((ret = sctp_get_port_local(sk, addr))) { return -EADDRINUSE; } /* Refresh ephemeral port. */ if (!bp->port) bp->port = inet_sk(sk)->inet_num; /* Add the address to the bind address list. * Use GFP_ATOMIC since BHs will be disabled. */ ret = sctp_add_bind_addr(bp, addr, SCTP_ADDR_SRC, GFP_ATOMIC); /* Copy back into socket for getsockname() use. */ if (!ret) { inet_sk(sk)->inet_sport = htons(inet_sk(sk)->inet_num); af->to_sk_saddr(addr, sk); } return ret; } /* 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). */ static int sctp_send_asconf(struct sctp_association *asoc, struct sctp_chunk *chunk) { struct net *net = sock_net(asoc->base.sk); int retval = 0; /* If there is an outstanding ASCONF chunk, queue it for later * transmission. */ if (asoc->addip_last_asconf) { list_add_tail(&chunk->list, &asoc->addip_chunk_list); goto out; } /* Hold the chunk until an ASCONF_ACK is received. */ sctp_chunk_hold(chunk); retval = sctp_primitive_ASCONF(net, asoc, chunk); if (retval) sctp_chunk_free(chunk); else asoc->addip_last_asconf = chunk; out: return retval; } /* Add a list of addresses as bind addresses to local endpoint or * association. * * Basically run through each address specified in the addrs/addrcnt * array/length pair, determine if it is IPv6 or IPv4 and call * sctp_do_bind() on it. * * If any of them fails, then the operation will be reversed and the * ones that were added will be removed. * * Only sctp_setsockopt_bindx() is supposed to call this function. */ static int sctp_bindx_add(struct sock *sk, struct sockaddr *addrs, int addrcnt) { int cnt; int retval = 0; void *addr_buf; struct sockaddr *sa_addr; struct sctp_af *af; SCTP_DEBUG_PRINTK("sctp_bindx_add (sk: %p, addrs: %p, addrcnt: %d)\n", sk, addrs, addrcnt); addr_buf = addrs; for (cnt = 0; cnt < addrcnt; cnt++) { /* The list may contain either IPv4 or IPv6 address; * determine the address length for walking thru the list. */ sa_addr = addr_buf; af = sctp_get_af_specific(sa_addr->sa_family); if (!af) { retval = -EINVAL; goto err_bindx_add; } retval = sctp_do_bind(sk, (union sctp_addr *)sa_addr, af->sockaddr_len); addr_buf += af->sockaddr_len; err_bindx_add: if (retval < 0) { /* Failed. Cleanup the ones that have been added */ if (cnt > 0) sctp_bindx_rem(sk, addrs, cnt); return retval; } } return retval; } /* Send an ASCONF chunk with Add IP address parameters to all the peers of the * associations that are part of the endpoint indicating that a list of local * addresses are added to the endpoint. * * If any of the addresses is already in the bind address list of the * association, we do not send the chunk for that association. But it will not * affect other associations. * * Only sctp_setsockopt_bindx() is supposed to call this function. */ static int sctp_send_asconf_add_ip(struct sock *sk, struct sockaddr *addrs, int addrcnt) { struct net *net = sock_net(sk); struct sctp_sock *sp; struct sctp_endpoint *ep; struct sctp_association *asoc; struct sctp_bind_addr *bp; struct sctp_chunk *chunk; struct sctp_sockaddr_entry *laddr; union sctp_addr *addr; union sctp_addr saveaddr; void *addr_buf; struct sctp_af *af; struct list_head *p; int i; int retval = 0; if (!net->sctp.addip_enable) return retval; sp = sctp_sk(sk); ep = sp->ep; SCTP_DEBUG_PRINTK("%s: (sk: %p, addrs: %p, addrcnt: %d)\n", __func__, sk, addrs, addrcnt); list_for_each_entry(asoc, &ep->asocs, asocs) { if (!asoc->peer.asconf_capable) continue; if (asoc->peer.addip_disabled_mask & SCTP_PARAM_ADD_IP) continue; if (!sctp_state(asoc, ESTABLISHED)) continue; /* Check if any address in the packed array of addresses is * in the bind address list of the association. If so, * do not send the asconf chunk to its peer, but continue with * other associations. */ addr_buf = addrs; for (i = 0; i < addrcnt; i++) { addr = addr_buf; af = sctp_get_af_specific(addr->v4.sin_family); if (!af) { retval = -EINVAL; goto out; } if (sctp_assoc_lookup_laddr(asoc, addr)) break; addr_buf += af->sockaddr_len; } if (i < addrcnt) continue; /* Use the first valid address in bind addr list of * association as Address Parameter of ASCONF CHUNK. */ bp = &asoc->base.bind_addr; p = bp->address_list.next; laddr = list_entry(p, struct sctp_sockaddr_entry, list); chunk = sctp_make_asconf_update_ip(asoc, &laddr->a, addrs, addrcnt, SCTP_PARAM_ADD_IP); if (!chunk) { retval = -ENOMEM; goto out; } /* Add the new addresses to the bind address list with * use_as_src set to 0. */ addr_buf = addrs; for (i = 0; i < addrcnt; i++) { addr = addr_buf; af = sctp_get_af_specific(addr->v4.sin_family); memcpy(&saveaddr, addr, af->sockaddr_len); retval = sctp_add_bind_addr(bp, &saveaddr, SCTP_ADDR_NEW, GFP_ATOMIC); addr_buf += af->sockaddr_len; } if (asoc->src_out_of_asoc_ok) { struct sctp_transport *trans; list_for_each_entry(trans, &asoc->peer.transport_addr_list, transports) { /* Clear the source and route cache */ dst_release(trans->dst); trans->cwnd = min(4*asoc->pathmtu, max_t(__u32, 2*asoc->pathmtu, 4380)); trans->ssthresh = asoc->peer.i.a_rwnd; trans->rto = asoc->rto_initial; trans->rtt = trans->srtt = trans->rttvar = 0; sctp_transport_route(trans, NULL, sctp_sk(asoc->base.sk)); } } retval = sctp_send_asconf(asoc, chunk); } out: return retval; } /* Remove a list of addresses from bind addresses list. Do not remove the * last address. * * Basically run through each address specified in the addrs/addrcnt * array/length pair, determine if it is IPv6 or IPv4 and call * sctp_del_bind() on it. * * If any of them fails, then the operation will be reversed and the * ones that were removed will be added back. * * At least one address has to be left; if only one address is * available, the operation will return -EBUSY. * * Only sctp_setsockopt_bindx() is supposed to call this function. */ static int sctp_bindx_rem(struct sock *sk, struct sockaddr *addrs, int addrcnt) { struct sctp_sock *sp = sctp_sk(sk); struct sctp_endpoint *ep = sp->ep; int cnt; struct sctp_bind_addr *bp = &ep->base.bind_addr; int retval = 0; void *addr_buf; union sctp_addr *sa_addr; struct sctp_af *af; SCTP_DEBUG_PRINTK("sctp_bindx_rem (sk: %p, addrs: %p, addrcnt: %d)\n", sk, addrs, addrcnt); addr_buf = addrs; for (cnt = 0; cnt < addrcnt; cnt++) { /* If the bind address list is empty or if there is only one * bind address, there is nothing more to be removed (we need * at least one address here). */ if (list_empty(&bp->address_list) || (sctp_list_single_entry(&bp->address_list))) { retval = -EBUSY; goto err_bindx_rem; } sa_addr = addr_buf; af = sctp_get_af_specific(sa_addr->sa.sa_family); if (!af) { retval = -EINVAL; goto err_bindx_rem; } if (!af->addr_valid(sa_addr, sp, NULL)) { retval = -EADDRNOTAVAIL; goto err_bindx_rem; } if (sa_addr->v4.sin_port && sa_addr->v4.sin_port != htons(bp->port)) { retval = -EINVAL; goto err_bindx_rem; } if (!sa_addr->v4.sin_port) sa_addr->v4.sin_port = htons(bp->port); /* FIXME - There is probably a need to check if sk->sk_saddr and * sk->sk_rcv_addr are currently set to one of the addresses to * be removed. This is something which needs to be looked into * when we are fixing the outstanding issues with multi-homing * socket routing and failover schemes. Refer to comments in * sctp_do_bind(). -daisy */ retval = sctp_del_bind_addr(bp, sa_addr); addr_buf += af->sockaddr_len; err_bindx_rem: if (retval < 0) { /* Failed. Add the ones that has been removed back */ if (cnt > 0) sctp_bindx_add(sk, addrs, cnt); return retval; } } return retval; } /* Send an ASCONF chunk with Delete IP address parameters to all the peers of * the associations that are part of the endpoint indicating that a list of * local addresses are removed from the endpoint. * * If any of the addresses is already in the bind address list of the * association, we do not send the chunk for that association. But it will not * affect other associations. * * Only sctp_setsockopt_bindx() is supposed to call this function. */ static int sctp_send_asconf_del_ip(struct sock *sk, struct sockaddr *addrs, int addrcnt) { struct net *net = sock_net(sk); struct sctp_sock *sp; struct sctp_endpoint *ep; struct sctp_association *asoc; struct sctp_transport *transport; struct sctp_bind_addr *bp; struct sctp_chunk *chunk; union sctp_addr *laddr; void *addr_buf; struct sctp_af *af; struct sctp_sockaddr_entry *saddr; int i; int retval = 0; int stored = 0; chunk = NULL; if (!net->sctp.addip_enable) return retval; sp = sctp_sk(sk); ep = sp->ep; SCTP_DEBUG_PRINTK("%s: (sk: %p, addrs: %p, addrcnt: %d)\n", __func__, sk, addrs, addrcnt); list_for_each_entry(asoc, &ep->asocs, asocs) { if (!asoc->peer.asconf_capable) continue; if (asoc->peer.addip_disabled_mask & SCTP_PARAM_DEL_IP) continue; if (!sctp_state(asoc, ESTABLISHED)) continue; /* Check if any address in the packed array of addresses is * not present in the bind address list of the association. * If so, do not send the asconf chunk to its peer, but * continue with other associations. */ addr_buf = addrs; for (i = 0; i < addrcnt; i++) { laddr = addr_buf; af = sctp_get_af_specific(laddr->v4.sin_family); if (!af) { retval = -EINVAL; goto out; } if (!sctp_assoc_lookup_laddr(asoc, laddr)) break; addr_buf += af->sockaddr_len; } if (i < addrcnt) continue; /* Find one address in the association's bind address list * that is not in the packed array of addresses. This is to * make sure that we do not delete all the addresses in the * association. */ bp = &asoc->base.bind_addr; laddr = sctp_find_unmatch_addr(bp, (union sctp_addr *)addrs, addrcnt, sp); if ((laddr == NULL) && (addrcnt == 1)) { if (asoc->asconf_addr_del_pending) continue; asoc->asconf_addr_del_pending = kzalloc(sizeof(union sctp_addr), GFP_ATOMIC); if (asoc->asconf_addr_del_pending == NULL) { retval = -ENOMEM; goto out; } asoc->asconf_addr_del_pending->sa.sa_family = addrs->sa_family; asoc->asconf_addr_del_pending->v4.sin_port = htons(bp->port); if (addrs->sa_family == AF_INET) { struct sockaddr_in *sin; sin = (struct sockaddr_in *)addrs; asoc->asconf_addr_del_pending->v4.sin_addr.s_addr = sin->sin_addr.s_addr; } else if (addrs->sa_family == AF_INET6) { struct sockaddr_in6 *sin6; sin6 = (struct sockaddr_in6 *)addrs; asoc->asconf_addr_del_pending->v6.sin6_addr = sin6->sin6_addr; } SCTP_DEBUG_PRINTK_IPADDR("send_asconf_del_ip: keep the last address asoc: %p ", " at %p\n", asoc, asoc->asconf_addr_del_pending, asoc->asconf_addr_del_pending); asoc->src_out_of_asoc_ok = 1; stored = 1; goto skip_mkasconf; } /* We do not need RCU protection throughout this loop * because this is done under a socket lock from the * setsockopt call. */ chunk = sctp_make_asconf_update_ip(asoc, laddr, addrs, addrcnt, SCTP_PARAM_DEL_IP); if (!chunk) { retval = -ENOMEM; goto out; } skip_mkasconf: /* Reset use_as_src flag for the addresses in the bind address * list that are to be deleted. */ addr_buf = addrs; for (i = 0; i < addrcnt; i++) { laddr = addr_buf; af = sctp_get_af_specific(laddr->v4.sin_family); list_for_each_entry(saddr, &bp->address_list, list) { if (sctp_cmp_addr_exact(&saddr->a, laddr)) saddr->state = SCTP_ADDR_DEL; } addr_buf += af->sockaddr_len; } /* Update the route and saddr entries for all the transports * as some of the addresses in the bind address list are * about to be deleted and cannot be used as source addresses. */ list_for_each_entry(transport, &asoc->peer.transport_addr_list, transports) { dst_release(transport->dst); sctp_transport_route(transport, NULL, sctp_sk(asoc->base.sk)); } if (stored) /* We don't need to transmit ASCONF */ continue; retval = sctp_send_asconf(asoc, chunk); } out: return retval; } /* set addr events to assocs in the endpoint. ep and addr_wq must be locked */ int sctp_asconf_mgmt(struct sctp_sock *sp, struct sctp_sockaddr_entry *addrw) { struct sock *sk = sctp_opt2sk(sp); union sctp_addr *addr; struct sctp_af *af; /* It is safe to write port space in caller. */ addr = &addrw->a; addr->v4.sin_port = htons(sp->ep->base.bind_addr.port); af = sctp_get_af_specific(addr->sa.sa_family); if (!af) return -EINVAL; if (sctp_verify_addr(sk, addr, af->sockaddr_len)) return -EINVAL; if (addrw->state == SCTP_ADDR_NEW) return sctp_send_asconf_add_ip(sk, (struct sockaddr *)addr, 1); else return sctp_send_asconf_del_ip(sk, (struct sockaddr *)addr, 1); } /* Helper for tunneling sctp_bindx() requests through sctp_setsockopt() * * API 8.1 * int sctp_bindx(int sd, struct sockaddr *addrs, int addrcnt, * int flags); * * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses. * If the sd is an IPv6 socket, the addresses passed can either be IPv4 * or IPv6 addresses. * * A single address may be specified as INADDR_ANY or IN6ADDR_ANY, see * Section 3.1.2 for this usage. * * addrs is a pointer to an array of one or more socket addresses. Each * address is contained in its appropriate structure (i.e. struct * sockaddr_in or struct sockaddr_in6) the family of the address type * must be used to distinguish the address length (note that this * representation is termed a "packed array" of addresses). The caller * specifies the number of addresses in the array with addrcnt. * * On success, sctp_bindx() returns 0. On failure, sctp_bindx() returns * -1, and sets errno to the appropriate error code. * * For SCTP, the port given in each socket address must be the same, or * sctp_bindx() will fail, setting errno to EINVAL. * * The flags parameter is formed from the bitwise OR of zero or more of * the following currently defined flags: * * SCTP_BINDX_ADD_ADDR * * SCTP_BINDX_REM_ADDR * * SCTP_BINDX_ADD_ADDR directs SCTP to add the given addresses to the * association, and SCTP_BINDX_REM_ADDR directs SCTP to remove the given * addresses from the association. The two flags are mutually exclusive; * if both are given, sctp_bindx() will fail with EINVAL. A caller may * not remove all addresses from an association; sctp_bindx() will * reject such an attempt with EINVAL. * * An application can use sctp_bindx(SCTP_BINDX_ADD_ADDR) to associate * additional addresses with an endpoint after calling bind(). Or use * sctp_bindx(SCTP_BINDX_REM_ADDR) to remove some addresses a listening * socket is associated with so that no new association accepted will be * associated with those addresses. If the endpoint supports dynamic * address a SCTP_BINDX_REM_ADDR or SCTP_BINDX_ADD_ADDR may cause a * endpoint to send the appropriate message to the peer to change the * peers address lists. * * Adding and removing addresses from a connected association is * optional functionality. Implementations that do not support this * functionality should return EOPNOTSUPP. * * Basically do nothing but copying the addresses from user to kernel * land and invoking either sctp_bindx_add() or sctp_bindx_rem() on the sk. * This is used for tunneling the sctp_bindx() request through sctp_setsockopt() * from userspace. * * We don't use copy_from_user() for optimization: we first do the * sanity checks (buffer size -fast- and access check-healthy * pointer); if all of those succeed, then we can alloc the memory * (expensive operation) needed to copy the data to kernel. Then we do * the copying without checking the user space area * (__copy_from_user()). * * On exit there is no need to do sockfd_put(), sys_setsockopt() does * it. * * sk The sk of the socket * addrs The pointer to the addresses in user land * addrssize Size of the addrs buffer * op Operation to perform (add or remove, see the flags of * sctp_bindx) * * Returns 0 if ok, <0 errno code on error. */ SCTP_STATIC int sctp_setsockopt_bindx(struct sock* sk, struct sockaddr __user *addrs, int addrs_size, int op) { struct sockaddr *kaddrs; int err; int addrcnt = 0; int walk_size = 0; struct sockaddr *sa_addr; void *addr_buf; struct sctp_af *af; SCTP_DEBUG_PRINTK("sctp_setsockopt_bindx: sk %p addrs %p" " addrs_size %d opt %d\n", sk, addrs, addrs_size, op); if (unlikely(addrs_size <= 0)) return -EINVAL; /* Check the user passed a healthy pointer. */ if (unlikely(!access_ok(VERIFY_READ, addrs, addrs_size))) return -EFAULT; /* Alloc space for the address array in kernel memory. */ kaddrs = kmalloc(addrs_size, GFP_KERNEL); if (unlikely(!kaddrs)) return -ENOMEM; if (__copy_from_user(kaddrs, addrs, addrs_size)) { kfree(kaddrs); return -EFAULT; } /* Walk through the addrs buffer and count the number of addresses. */ addr_buf = kaddrs; while (walk_size < addrs_size) { if (walk_size + sizeof(sa_family_t) > addrs_size) { kfree(kaddrs); return -EINVAL; } sa_addr = addr_buf; af = sctp_get_af_specific(sa_addr->sa_family); /* If the address family is not supported or if this address * causes the address buffer to overflow return EINVAL. */ if (!af || (walk_size + af->sockaddr_len) > addrs_size) { kfree(kaddrs); return -EINVAL; } addrcnt++; addr_buf += af->sockaddr_len; walk_size += af->sockaddr_len; } /* Do the work. */ switch (op) { case SCTP_BINDX_ADD_ADDR: err = sctp_bindx_add(sk, kaddrs, addrcnt); if (err) goto out; err = sctp_send_asconf_add_ip(sk, kaddrs, addrcnt); break; case SCTP_BINDX_REM_ADDR: err = sctp_bindx_rem(sk, kaddrs, addrcnt); if (err) goto out; err = sctp_send_asconf_del_ip(sk, kaddrs, addrcnt); break; default: err = -EINVAL; break; } out: kfree(kaddrs); return err; } /* __sctp_connect(struct sock* sk, struct sockaddr *kaddrs, int addrs_size) * * Common routine for handling connect() and sctp_connectx(). * Connect will come in with just a single address. */ static int __sctp_connect(struct sock* sk, struct sockaddr *kaddrs, int addrs_size, sctp_assoc_t *assoc_id) { struct net *net = sock_net(sk); struct sctp_sock *sp; struct sctp_endpoint *ep; struct sctp_association *asoc = NULL; struct sctp_association *asoc2; struct sctp_transport *transport; union sctp_addr to; struct sctp_af *af; sctp_scope_t scope; long timeo; int err = 0; int addrcnt = 0; int walk_size = 0; union sctp_addr *sa_addr = NULL; void *addr_buf; unsigned short port; unsigned int f_flags = 0; sp = sctp_sk(sk); ep = sp->ep; /* connect() cannot be done on a socket that is already in ESTABLISHED * state - UDP-style peeled off socket or a TCP-style socket that * is already connected. * It cannot be done even on a TCP-style listening socket. */ if (sctp_sstate(sk, ESTABLISHED) || (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))) { err = -EISCONN; goto out_free; } /* Walk through the addrs buffer and count the number of addresses. */ addr_buf = kaddrs; while (walk_size < addrs_size) { if (walk_size + sizeof(sa_family_t) > addrs_size) { err = -EINVAL; goto out_free; } sa_addr = addr_buf; af = sctp_get_af_specific(sa_addr->sa.sa_family); /* If the address family is not supported or if this address * causes the address buffer to overflow return EINVAL. */ if (!af || (walk_size + af->sockaddr_len) > addrs_size) { err = -EINVAL; goto out_free; } port = ntohs(sa_addr->v4.sin_port); /* Save current address so we can work with it */ memcpy(&to, sa_addr, af->sockaddr_len); err = sctp_verify_addr(sk, &to, af->sockaddr_len); if (err) goto out_free; /* Make sure the destination port is correctly set * in all addresses. */ if (asoc && asoc->peer.port && asoc->peer.port != port) goto out_free; /* Check if there already is a matching association on the * endpoint (other than the one created here). */ asoc2 = sctp_endpoint_lookup_assoc(ep, &to, &transport); if (asoc2 && asoc2 != asoc) { if (asoc2->state >= SCTP_STATE_ESTABLISHED) err = -EISCONN; else err = -EALREADY; goto out_free; } /* If we could not find a matching association on the endpoint, * make sure that there is no peeled-off association matching * the peer address even on another socket. */ if (sctp_endpoint_is_peeled_off(ep, &to)) { err = -EADDRNOTAVAIL; goto out_free; } if (!asoc) { /* If a bind() or sctp_bindx() is not called prior to * an sctp_connectx() call, the system picks an * ephemeral port and will choose an address set * equivalent to binding with a wildcard address. */ if (!ep->base.bind_addr.port) { if (sctp_autobind(sk)) { err = -EAGAIN; goto out_free; } } else { /* * If an unprivileged user inherits a 1-many * style socket with open associations on a * privileged port, it MAY be permitted to * accept new associations, but it SHOULD NOT * be permitted to open new associations. */ if (ep->base.bind_addr.port < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE)) { err = -EACCES; goto out_free; } } scope = sctp_scope(&to); asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL); if (!asoc) { err = -ENOMEM; goto out_free; } err = sctp_assoc_set_bind_addr_from_ep(asoc, scope, GFP_KERNEL); if (err < 0) { goto out_free; } } /* Prime the peer's transport structures. */ transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL, SCTP_UNKNOWN); if (!transport) { err = -ENOMEM; goto out_free; } addrcnt++; addr_buf += af->sockaddr_len; walk_size += af->sockaddr_len; } /* In case the user of sctp_connectx() wants an association * id back, assign one now. */ if (assoc_id) { err = sctp_assoc_set_id(asoc, GFP_KERNEL); if (err < 0) goto out_free; } err = sctp_primitive_ASSOCIATE(net, asoc, NULL); if (err < 0) { goto out_free; } /* Initialize sk's dport and daddr for getpeername() */ inet_sk(sk)->inet_dport = htons(asoc->peer.port); af = sctp_get_af_specific(sa_addr->sa.sa_family); af->to_sk_daddr(sa_addr, sk); sk->sk_err = 0; /* in-kernel sockets don't generally have a file allocated to them * if all they do is call sock_create_kern(). */ if (sk->sk_socket->file) f_flags = sk->sk_socket->file->f_flags; timeo = sock_sndtimeo(sk, f_flags & O_NONBLOCK); err = sctp_wait_for_connect(asoc, &timeo); if ((err == 0 || err == -EINPROGRESS) && assoc_id) *assoc_id = asoc->assoc_id; /* Don't free association on exit. */ asoc = NULL; out_free: SCTP_DEBUG_PRINTK("About to exit __sctp_connect() free asoc: %p" " kaddrs: %p err: %d\n", asoc, kaddrs, err); if (asoc) { /* sctp_primitive_ASSOCIATE may have added this association * To the hash table, try to unhash it, just in case, its a noop * if it wasn't hashed so we're safe */ sctp_unhash_established(asoc); sctp_association_free(asoc); } return err; } /* Helper for tunneling sctp_connectx() requests through sctp_setsockopt() * * API 8.9 * int sctp_connectx(int sd, struct sockaddr *addrs, int addrcnt, * sctp_assoc_t *asoc); * * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses. * If the sd is an IPv6 socket, the addresses passed can either be IPv4 * or IPv6 addresses. * * A single address may be specified as INADDR_ANY or IN6ADDR_ANY, see * Section 3.1.2 for this usage. * * addrs is a pointer to an array of one or more socket addresses. Each * address is contained in its appropriate structure (i.e. struct * sockaddr_in or struct sockaddr_in6) the family of the address type * must be used to distengish the address length (note that this * representation is termed a "packed array" of addresses). The caller * specifies the number of addresses in the array with addrcnt. * * On success, sctp_connectx() returns 0. It also sets the assoc_id to * the association id of the new association. On failure, sctp_connectx() * returns -1, and sets errno to the appropriate error code. The assoc_id * is not touched by the kernel. * * For SCTP, the port given in each socket address must be the same, or * sctp_connectx() will fail, setting errno to EINVAL. * * An application can use sctp_connectx to initiate an association with * an endpoint that is multi-homed. Much like sctp_bindx() this call * allows a caller to specify multiple addresses at which a peer can be * reached. The way the SCTP stack uses the list of addresses to set up * the association is implementation dependent. This function only * specifies that the stack will try to make use of all the addresses in * the list when needed. * * Note that the list of addresses passed in is only used for setting up * the association. It does not necessarily equal the set of addresses * the peer uses for the resulting association. If the caller wants to * find out the set of peer addresses, it must use sctp_getpaddrs() to * retrieve them after the association has been set up. * * Basically do nothing but copying the addresses from user to kernel * land and invoking either sctp_connectx(). This is used for tunneling * the sctp_connectx() request through sctp_setsockopt() from userspace. * * We don't use copy_from_user() for optimization: we first do the * sanity checks (buffer size -fast- and access check-healthy * pointer); if all of those succeed, then we can alloc the memory * (expensive operation) needed to copy the data to kernel. Then we do * the copying without checking the user space area * (__copy_from_user()). * * On exit there is no need to do sockfd_put(), sys_setsockopt() does * it. * * sk The sk of the socket * addrs The pointer to the addresses in user land * addrssize Size of the addrs buffer * * Returns >=0 if ok, <0 errno code on error. */ SCTP_STATIC int __sctp_setsockopt_connectx(struct sock* sk, struct sockaddr __user *addrs, int addrs_size, sctp_assoc_t *assoc_id) { int err = 0; struct sockaddr *kaddrs; SCTP_DEBUG_PRINTK("%s - sk %p addrs %p addrs_size %d\n", __func__, sk, addrs, addrs_size); if (unlikely(addrs_size <= 0)) return -EINVAL; /* Check the user passed a healthy pointer. */ if (unlikely(!access_ok(VERIFY_READ, addrs, addrs_size))) return -EFAULT; /* Alloc space for the address array in kernel memory. */ kaddrs = kmalloc(addrs_size, GFP_KERNEL); if (unlikely(!kaddrs)) return -ENOMEM; if (__copy_from_user(kaddrs, addrs, addrs_size)) { err = -EFAULT; } else { err = __sctp_connect(sk, kaddrs, addrs_size, assoc_id); } kfree(kaddrs); return err; } /* * This is an older interface. It's kept for backward compatibility * to the option that doesn't provide association id. */ SCTP_STATIC int sctp_setsockopt_connectx_old(struct sock* sk, struct sockaddr __user *addrs, int addrs_size) { return __sctp_setsockopt_connectx(sk, addrs, addrs_size, NULL); } /* * New interface for the API. The since the API is done with a socket * option, to make it simple we feed back the association id is as a return * indication to the call. Error is always negative and association id is * always positive. */ SCTP_STATIC int sctp_setsockopt_connectx(struct sock* sk, struct sockaddr __user *addrs, int addrs_size) { sctp_assoc_t assoc_id = 0; int err = 0; err = __sctp_setsockopt_connectx(sk, addrs, addrs_size, &assoc_id); if (err) return err; else return assoc_id; } /* * New (hopefully final) interface for the API. * We use the sctp_getaddrs_old structure so that use-space library * can avoid any unnecessary allocations. The only defferent part * is that we store the actual length of the address buffer into the * addrs_num structure member. That way we can re-use the existing * code. */ SCTP_STATIC int sctp_getsockopt_connectx3(struct sock* sk, int len, char __user *optval, int __user *optlen) { struct sctp_getaddrs_old param; sctp_assoc_t assoc_id = 0; int err = 0; if (len < sizeof(param)) return -EINVAL; if (copy_from_user(¶m, optval, sizeof(param))) return -EFAULT; err = __sctp_setsockopt_connectx(sk, (struct sockaddr __user *)param.addrs, param.addr_num, &assoc_id); if (err == 0 || err == -EINPROGRESS) { if (copy_to_user(optval, &assoc_id, sizeof(assoc_id))) return -EFAULT; if (put_user(sizeof(assoc_id), optlen)) return -EFAULT; } return err; } /* API 3.1.4 close() - UDP Style Syntax * Applications use close() to perform graceful shutdown (as described in * Section 10.1 of [SCTP]) on ALL the associations currently represented * by a UDP-style socket. * * The syntax is * * ret = close(int sd); * * sd - the socket descriptor of the associations to be closed. * * To gracefully shutdown a specific association represented by the * UDP-style socket, an application should use the sendmsg() call, * passing no user data, but including the appropriate flag in the * ancillary data (see Section xxxx). * * If sd in the close() call is a branched-off socket representing only * one association, the shutdown is performed on that association only. * * 4.1.6 close() - TCP Style Syntax * * Applications use close() to gracefully close down an association. * * The syntax is: * * int close(int sd); * * sd - the socket descriptor of the association to be closed. * * After an application calls close() on a socket descriptor, no further * socket operations will succeed on that descriptor. * * API 7.1.4 SO_LINGER * * An application using the TCP-style socket can use this option to * perform the SCTP ABORT primitive. The linger option structure is: * * struct linger { * int l_onoff; // option on/off * int l_linger; // linger time * }; * * To enable the option, set l_onoff to 1. If the l_linger value is set * to 0, calling close() is the same as the ABORT primitive. If the * value is set to a negative value, the setsockopt() call will return * an error. If the value is set to a positive value linger_time, the * close() can be blocked for at most linger_time ms. If the graceful * shutdown phase does not finish during this period, close() will * return but the graceful shutdown phase continues in the system. */ SCTP_STATIC void sctp_close(struct sock *sk, long timeout) { struct net *net = sock_net(sk); struct sctp_endpoint *ep; struct sctp_association *asoc; struct list_head *pos, *temp; unsigned int data_was_unread; SCTP_DEBUG_PRINTK("sctp_close(sk: 0x%p, timeout:%ld)\n", sk, timeout); sctp_lock_sock(sk); sk->sk_shutdown = SHUTDOWN_MASK; sk->sk_state = SCTP_SS_CLOSING; ep = sctp_sk(sk)->ep; /* Clean up any skbs sitting on the receive queue. */ data_was_unread = sctp_queue_purge_ulpevents(&sk->sk_receive_queue); data_was_unread += sctp_queue_purge_ulpevents(&sctp_sk(sk)->pd_lobby); /* Walk all associations on an endpoint. */ list_for_each_safe(pos, temp, &ep->asocs) { asoc = list_entry(pos, struct sctp_association, asocs); if (sctp_style(sk, TCP)) { /* A closed association can still be in the list if * it belongs to a TCP-style listening socket that is * not yet accepted. If so, free it. If not, send an * ABORT or SHUTDOWN based on the linger options. */ if (sctp_state(asoc, CLOSED)) { sctp_unhash_established(asoc); sctp_association_free(asoc); continue; } } if (data_was_unread || !skb_queue_empty(&asoc->ulpq.lobby) || !skb_queue_empty(&asoc->ulpq.reasm) || (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime)) { struct sctp_chunk *chunk; chunk = sctp_make_abort_user(asoc, NULL, 0); if (chunk) sctp_primitive_ABORT(net, asoc, chunk); } else sctp_primitive_SHUTDOWN(net, asoc, NULL); } /* On a TCP-style socket, block for at most linger_time if set. */ if (sctp_style(sk, TCP) && timeout) sctp_wait_for_close(sk, timeout); /* This will run the backlog queue. */ sctp_release_sock(sk); /* Supposedly, no process has access to the socket, but * the net layers still may. */ sctp_local_bh_disable(); sctp_bh_lock_sock(sk); /* Hold the sock, since sk_common_release() will put sock_put() * and we have just a little more cleanup. */ sock_hold(sk); sk_common_release(sk); sctp_bh_unlock_sock(sk); sctp_local_bh_enable(); sock_put(sk); SCTP_DBG_OBJCNT_DEC(sock); } /* Handle EPIPE error. */ static int sctp_error(struct sock *sk, int flags, int err) { if (err == -EPIPE) err = sock_error(sk) ? : -EPIPE; if (err == -EPIPE && !(flags & MSG_NOSIGNAL)) send_sig(SIGPIPE, current, 0); return err; } /* API 3.1.3 sendmsg() - UDP Style Syntax * * An application uses sendmsg() and recvmsg() calls to transmit data to * and receive data from its peer. * * ssize_t sendmsg(int socket, const struct msghdr *message, * int flags); * * socket - the socket descriptor of the endpoint. * message - pointer to the msghdr structure which contains a single * user message and possibly some ancillary data. * * See Section 5 for complete description of the data * structures. * * flags - flags sent or received with the user message, see Section * 5 for complete description of the flags. * * Note: This function could use a rewrite especially when explicit * connect support comes in. */ /* BUG: We do not implement the equivalent of sk_stream_wait_memory(). */ SCTP_STATIC int sctp_msghdr_parse(const struct msghdr *, sctp_cmsgs_t *); SCTP_STATIC int sctp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, size_t msg_len) { struct net *net = sock_net(sk); struct sctp_sock *sp; struct sctp_endpoint *ep; struct sctp_association *new_asoc=NULL, *asoc=NULL; struct sctp_transport *transport, *chunk_tp; struct sctp_chunk *chunk; union sctp_addr to; struct sockaddr *msg_name = NULL; struct sctp_sndrcvinfo default_sinfo; struct sctp_sndrcvinfo *sinfo; struct sctp_initmsg *sinit; sctp_assoc_t associd = 0; sctp_cmsgs_t cmsgs = { NULL }; int err; sctp_scope_t scope; long timeo; __u16 sinfo_flags = 0; struct sctp_datamsg *datamsg; int msg_flags = msg->msg_flags; SCTP_DEBUG_PRINTK("sctp_sendmsg(sk: %p, msg: %p, msg_len: %zu)\n", sk, msg, msg_len); err = 0; sp = sctp_sk(sk); ep = sp->ep; SCTP_DEBUG_PRINTK("Using endpoint: %p.\n", ep); /* We cannot send a message over a TCP-style listening socket. */ if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING)) { err = -EPIPE; goto out_nounlock; } /* Parse out the SCTP CMSGs. */ err = sctp_msghdr_parse(msg, &cmsgs); if (err) { SCTP_DEBUG_PRINTK("msghdr parse err = %x\n", err); goto out_nounlock; } /* Fetch the destination address for this packet. This * address only selects the association--it is not necessarily * the address we will send to. * For a peeled-off socket, msg_name is ignored. */ if (!sctp_style(sk, UDP_HIGH_BANDWIDTH) && msg->msg_name) { int msg_namelen = msg->msg_namelen; err = sctp_verify_addr(sk, (union sctp_addr *)msg->msg_name, msg_namelen); if (err) return err; if (msg_namelen > sizeof(to)) msg_namelen = sizeof(to); memcpy(&to, msg->msg_name, msg_namelen); msg_name = msg->msg_name; } sinfo = cmsgs.info; sinit = cmsgs.init; /* Did the user specify SNDRCVINFO? */ if (sinfo) { sinfo_flags = sinfo->sinfo_flags; associd = sinfo->sinfo_assoc_id; } SCTP_DEBUG_PRINTK("msg_len: %zu, sinfo_flags: 0x%x\n", msg_len, sinfo_flags); /* SCTP_EOF or SCTP_ABORT cannot be set on a TCP-style socket. */ if (sctp_style(sk, TCP) && (sinfo_flags & (SCTP_EOF | SCTP_ABORT))) { err = -EINVAL; goto out_nounlock; } /* If SCTP_EOF is set, no data can be sent. Disallow sending zero * length messages when SCTP_EOF|SCTP_ABORT is not set. * If SCTP_ABORT is set, the message length could be non zero with * the msg_iov set to the user abort reason. */ if (((sinfo_flags & SCTP_EOF) && (msg_len > 0)) || (!(sinfo_flags & (SCTP_EOF|SCTP_ABORT)) && (msg_len == 0))) { err = -EINVAL; goto out_nounlock; } /* If SCTP_ADDR_OVER is set, there must be an address * specified in msg_name. */ if ((sinfo_flags & SCTP_ADDR_OVER) && (!msg->msg_name)) { err = -EINVAL; goto out_nounlock; } transport = NULL; SCTP_DEBUG_PRINTK("About to look up association.\n"); sctp_lock_sock(sk); /* If a msg_name has been specified, assume this is to be used. */ if (msg_name) { /* Look for a matching association on the endpoint. */ asoc = sctp_endpoint_lookup_assoc(ep, &to, &transport); if (!asoc) { /* If we could not find a matching association on the * endpoint, make sure that it is not a TCP-style * socket that already has an association or there is * no peeled-off association on another socket. */ if ((sctp_style(sk, TCP) && sctp_sstate(sk, ESTABLISHED)) || sctp_endpoint_is_peeled_off(ep, &to)) { err = -EADDRNOTAVAIL; goto out_unlock; } } } else { asoc = sctp_id2assoc(sk, associd); if (!asoc) { err = -EPIPE; goto out_unlock; } } if (asoc) { SCTP_DEBUG_PRINTK("Just looked up association: %p.\n", asoc); /* We cannot send a message on a TCP-style SCTP_SS_ESTABLISHED * socket that has an association in CLOSED state. This can * happen when an accepted socket has an association that is * already CLOSED. */ if (sctp_state(asoc, CLOSED) && sctp_style(sk, TCP)) { err = -EPIPE; goto out_unlock; } if (sinfo_flags & SCTP_EOF) { SCTP_DEBUG_PRINTK("Shutting down association: %p\n", asoc); sctp_primitive_SHUTDOWN(net, asoc, NULL); err = 0; goto out_unlock; } if (sinfo_flags & SCTP_ABORT) { chunk = sctp_make_abort_user(asoc, msg, msg_len); if (!chunk) { err = -ENOMEM; goto out_unlock; } SCTP_DEBUG_PRINTK("Aborting association: %p\n", asoc); sctp_primitive_ABORT(net, asoc, chunk); err = 0; goto out_unlock; } } /* Do we need to create the association? */ if (!asoc) { SCTP_DEBUG_PRINTK("There is no association yet.\n"); if (sinfo_flags & (SCTP_EOF | SCTP_ABORT)) { err = -EINVAL; goto out_unlock; } /* Check for invalid stream against the stream counts, * either the default or the user specified stream counts. */ if (sinfo) { if (!sinit || (sinit && !sinit->sinit_num_ostreams)) { /* Check against the defaults. */ if (sinfo->sinfo_stream >= sp->initmsg.sinit_num_ostreams) { err = -EINVAL; goto out_unlock; } } else { /* Check against the requested. */ if (sinfo->sinfo_stream >= sinit->sinit_num_ostreams) { err = -EINVAL; goto out_unlock; } } } /* * API 3.1.2 bind() - UDP Style Syntax * If a bind() or sctp_bindx() is not called prior to a * sendmsg() call that initiates a new association, the * system picks an ephemeral port and will choose an address * set equivalent to binding with a wildcard address. */ if (!ep->base.bind_addr.port) { if (sctp_autobind(sk)) { err = -EAGAIN; goto out_unlock; } } else { /* * If an unprivileged user inherits a one-to-many * style socket with open associations on a privileged * port, it MAY be permitted to accept new associations, * but it SHOULD NOT be permitted to open new * associations. */ if (ep->base.bind_addr.port < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE)) { err = -EACCES; goto out_unlock; } } scope = sctp_scope(&to); new_asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL); if (!new_asoc) { err = -ENOMEM; goto out_unlock; } asoc = new_asoc; err = sctp_assoc_set_bind_addr_from_ep(asoc, scope, GFP_KERNEL); if (err < 0) { err = -ENOMEM; goto out_free; } /* If the SCTP_INIT ancillary data is specified, set all * the association init values accordingly. */ if (sinit) { if (sinit->sinit_num_ostreams) { asoc->c.sinit_num_ostreams = sinit->sinit_num_ostreams; } if (sinit->sinit_max_instreams) { asoc->c.sinit_max_instreams = sinit->sinit_max_instreams; } if (sinit->sinit_max_attempts) { asoc->max_init_attempts = sinit->sinit_max_attempts; } if (sinit->sinit_max_init_timeo) { asoc->max_init_timeo = msecs_to_jiffies(sinit->sinit_max_init_timeo); } } /* Prime the peer's transport structures. */ transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL, SCTP_UNKNOWN); if (!transport) { err = -ENOMEM; goto out_free; } } /* ASSERT: we have a valid association at this point. */ SCTP_DEBUG_PRINTK("We have a valid association.\n"); if (!sinfo) { /* If the user didn't specify SNDRCVINFO, make up one with * some defaults. */ memset(&default_sinfo, 0, sizeof(default_sinfo)); default_sinfo.sinfo_stream = asoc->default_stream; default_sinfo.sinfo_flags = asoc->default_flags; default_sinfo.sinfo_ppid = asoc->default_ppid; default_sinfo.sinfo_context = asoc->default_context; default_sinfo.sinfo_timetolive = asoc->default_timetolive; default_sinfo.sinfo_assoc_id = sctp_assoc2id(asoc); sinfo = &default_sinfo; } /* API 7.1.7, the sndbuf size per association bounds the * maximum size of data that can be sent in a single send call. */ if (msg_len > sk->sk_sndbuf) { err = -EMSGSIZE; goto out_free; } if (asoc->pmtu_pending) sctp_assoc_pending_pmtu(sk, asoc); /* If fragmentation is disabled and the message length exceeds the * association fragmentation point, return EMSGSIZE. The I-D * does not specify what this error is, but this looks like * a great fit. */ if (sctp_sk(sk)->disable_fragments && (msg_len > asoc->frag_point)) { err = -EMSGSIZE; goto out_free; } /* Check for invalid stream. */ if (sinfo->sinfo_stream >= asoc->c.sinit_num_ostreams) { err = -EINVAL; goto out_free; } timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); if (!sctp_wspace(asoc)) { err = sctp_wait_for_sndbuf(asoc, &timeo, msg_len); if (err) goto out_free; } /* If an address is passed with the sendto/sendmsg call, it is used * to override the primary destination address in the TCP model, or * when SCTP_ADDR_OVER flag is set in the UDP model. */ if ((sctp_style(sk, TCP) && msg_name) || (sinfo_flags & SCTP_ADDR_OVER)) { chunk_tp = sctp_assoc_lookup_paddr(asoc, &to); if (!chunk_tp) { err = -EINVAL; goto out_free; } } else chunk_tp = NULL; /* Auto-connect, if we aren't connected already. */ if (sctp_state(asoc, CLOSED)) { err = sctp_primitive_ASSOCIATE(net, asoc, NULL); if (err < 0) goto out_free; SCTP_DEBUG_PRINTK("We associated primitively.\n"); } /* Break the message into multiple chunks of maximum size. */ datamsg = sctp_datamsg_from_user(asoc, sinfo, msg, msg_len); if (!datamsg) { err = -ENOMEM; goto out_free; } /* Now send the (possibly) fragmented message. */ list_for_each_entry(chunk, &datamsg->chunks, frag_list) { sctp_chunk_hold(chunk); /* Do accounting for the write space. */ sctp_set_owner_w(chunk); chunk->transport = chunk_tp; } /* Send it to the lower layers. Note: all chunks * must either fail or succeed. The lower layer * works that way today. Keep it that way or this * breaks. */ err = sctp_primitive_SEND(net, asoc, datamsg); /* Did the lower layer accept the chunk? */ if (err) sctp_datamsg_free(datamsg); else sctp_datamsg_put(datamsg); SCTP_DEBUG_PRINTK("We sent primitively.\n"); if (err) goto out_free; else err = msg_len; /* If we are already past ASSOCIATE, the lower * layers are responsible for association cleanup. */ goto out_unlock; out_free: if (new_asoc) { sctp_unhash_established(asoc); sctp_association_free(asoc); } out_unlock: sctp_release_sock(sk); out_nounlock: return sctp_error(sk, msg_flags, err); #if 0 do_sock_err: if (msg_len) err = msg_len; else err = sock_error(sk); goto out; do_interrupted: if (msg_len) err = msg_len; goto out; #endif /* 0 */ } /* This is an extended version of skb_pull() that removes the data from the * start of a skb even when data is spread across the list of skb's in the * frag_list. len specifies the total amount of data that needs to be removed. * when 'len' bytes could be removed from the skb, it returns 0. * If 'len' exceeds the total skb length, it returns the no. of bytes that * could not be removed. */ static int sctp_skb_pull(struct sk_buff *skb, int len) { struct sk_buff *list; int skb_len = skb_headlen(skb); int rlen; if (len <= skb_len) { __skb_pull(skb, len); return 0; } len -= skb_len; __skb_pull(skb, skb_len); skb_walk_frags(skb, list) { rlen = sctp_skb_pull(list, len); skb->len -= (len-rlen); skb->data_len -= (len-rlen); if (!rlen) return 0; len = rlen; } return len; } /* API 3.1.3 recvmsg() - UDP Style Syntax * * ssize_t recvmsg(int socket, struct msghdr *message, * int flags); * * socket - the socket descriptor of the endpoint. * message - pointer to the msghdr structure which contains a single * user message and possibly some ancillary data. * * See Section 5 for complete description of the data * structures. * * flags - flags sent or received with the user message, see Section * 5 for complete description of the flags. */ static struct sk_buff *sctp_skb_recv_datagram(struct sock *, int, int, int *); SCTP_STATIC int sctp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, size_t len, int noblock, int flags, int *addr_len) { struct sctp_ulpevent *event = NULL; struct sctp_sock *sp = sctp_sk(sk); struct sk_buff *skb; int copied; int err = 0; int skb_len; SCTP_DEBUG_PRINTK("sctp_recvmsg(%s: %p, %s: %p, %s: %zd, %s: %d, %s: " "0x%x, %s: %p)\n", "sk", sk, "msghdr", msg, "len", len, "knoblauch", noblock, "flags", flags, "addr_len", addr_len); sctp_lock_sock(sk); if (sctp_style(sk, TCP) && !sctp_sstate(sk, ESTABLISHED)) { err = -ENOTCONN; goto out; } skb = sctp_skb_recv_datagram(sk, flags, noblock, &err); if (!skb) goto out; /* Get the total length of the skb including any skb's in the * frag_list. */ skb_len = skb->len; copied = skb_len; if (copied > len) copied = len; err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); event = sctp_skb2event(skb); if (err) goto out_free; sock_recv_ts_and_drops(msg, sk, skb); if (sctp_ulpevent_is_notification(event)) { msg->msg_flags |= MSG_NOTIFICATION; sp->pf->event_msgname(event, msg->msg_name, addr_len); } else { sp->pf->skb_msgname(skb, msg->msg_name, addr_len); } /* Check if we allow SCTP_SNDRCVINFO. */ if (sp->subscribe.sctp_data_io_event) sctp_ulpevent_read_sndrcvinfo(event, msg); #if 0 /* FIXME: we should be calling IP/IPv6 layers. */ if (sk->sk_protinfo.af_inet.cmsg_flags) ip_cmsg_recv(msg, skb); #endif err = copied; /* If skb's length exceeds the user's buffer, update the skb and * push it back to the receive_queue so that the next call to * recvmsg() will return the remaining data. Don't set MSG_EOR. */ if (skb_len > copied) { msg->msg_flags &= ~MSG_EOR; if (flags & MSG_PEEK) goto out_free; sctp_skb_pull(skb, copied); skb_queue_head(&sk->sk_receive_queue, skb); /* When only partial message is copied to the user, increase * rwnd by that amount. If all the data in the skb is read, * rwnd is updated when the event is freed. */ if (!sctp_ulpevent_is_notification(event)) sctp_assoc_rwnd_increase(event->asoc, copied); goto out; } else if ((event->msg_flags & MSG_NOTIFICATION) || (event->msg_flags & MSG_EOR)) msg->msg_flags |= MSG_EOR; else msg->msg_flags &= ~MSG_EOR; out_free: if (flags & MSG_PEEK) { /* Release the skb reference acquired after peeking the skb in * sctp_skb_recv_datagram(). */ kfree_skb(skb); } else { /* Free the event which includes releasing the reference to * the owner of the skb, freeing the skb and updating the * rwnd. */ sctp_ulpevent_free(event); } out: sctp_release_sock(sk); return err; } /* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS) * * This option is a on/off flag. If enabled no SCTP message * fragmentation will be performed. Instead if a message being sent * exceeds the current PMTU size, the message will NOT be sent and * instead a error will be indicated to the user. */ static int sctp_setsockopt_disable_fragments(struct sock *sk, char __user *optval, unsigned int optlen) { int val; if (optlen < sizeof(int)) return -EINVAL; if (get_user(val, (int __user *)optval)) return -EFAULT; sctp_sk(sk)->disable_fragments = (val == 0) ? 0 : 1; return 0; } static int sctp_setsockopt_events(struct sock *sk, char __user *optval, unsigned int optlen) { struct sctp_association *asoc; struct sctp_ulpevent *event; if (optlen > sizeof(struct sctp_event_subscribe)) return -EINVAL; if (copy_from_user(&sctp_sk(sk)->subscribe, optval, optlen)) return -EFAULT; /* * At the time when a user app subscribes to SCTP_SENDER_DRY_EVENT, * if there is no data to be sent or retransmit, the stack will * immediately send up this notification. */ if (sctp_ulpevent_type_enabled(SCTP_SENDER_DRY_EVENT, &sctp_sk(sk)->subscribe)) { asoc = sctp_id2assoc(sk, 0); if (asoc && sctp_outq_is_empty(&asoc->outqueue)) { event = sctp_ulpevent_make_sender_dry_event(asoc, GFP_ATOMIC); if (!event) return -ENOMEM; sctp_ulpq_tail_event(&asoc->ulpq, event); } } return 0; } /* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE) * * This socket option is applicable to the UDP-style socket only. When * set it will cause associations that are idle for more than the * specified number of seconds to automatically close. An association * being idle is defined an association that has NOT sent or received * user data. The special value of '0' indicates that no automatic * close of any associations should be performed. The option expects an * integer defining the number of seconds of idle time before an * association is closed. */ static int sctp_setsockopt_autoclose(struct sock *sk, char __user *optval, unsigned int optlen) { struct sctp_sock *sp = sctp_sk(sk); /* Applicable to UDP-style socket only */ if (sctp_style(sk, TCP)) return -EOPNOTSUPP; if (optlen != sizeof(int)) return -EINVAL; if (copy_from_user(&sp->autoclose, optval, optlen)) return -EFAULT; return 0; } /* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS) * * Applications can enable or disable heartbeats for any peer address of * an association, modify an address's heartbeat interval, force a * heartbeat to be sent immediately, and adjust the address's maximum * number of retransmissions sent before an address is considered * unreachable. The following structure is used to access and modify an * address's parameters: * * struct sctp_paddrparams { * sctp_assoc_t spp_assoc_id; * struct sockaddr_storage spp_address; * uint32_t spp_hbinterval; * uint16_t spp_pathmaxrxt; * uint32_t spp_pathmtu; * uint32_t spp_sackdelay; * uint32_t spp_flags; * }; * * spp_assoc_id - (one-to-many style socket) This is filled in the * application, and identifies the association for * this query. * spp_address - This specifies which address is of interest. * spp_hbinterval - This contains the value of the heartbeat i