diff options
Diffstat (limited to 'net/sctp/socket.c')
-rw-r--r-- | net/sctp/socket.c | 4797 |
1 files changed, 4797 insertions, 0 deletions
diff --git a/net/sctp/socket.c b/net/sctp/socket.c new file mode 100644 index 00000000000..e8c21018257 --- /dev/null +++ b/net/sctp/socket.c @@ -0,0 +1,4797 @@ +/* SCTP kernel reference Implementation + * (C) Copyright IBM Corp. 2001, 2004 + * Copyright (c) 1999-2000 Cisco, Inc. + * Copyright (c) 1999-2001 Motorola, Inc. + * Copyright (c) 2001-2003 Intel Corp. + * Copyright (c) 2001-2002 Nokia, Inc. + * Copyright (c) 2001 La Monte H.P. Yarroll + * + * This file is part of the SCTP kernel reference 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. + * + * The SCTP reference implementation is free software; + * you can redistribute it and/or modify it under the terms of + * the GNU General Public License as published by + * the Free Software Foundation; either version 2, or (at your option) + * any later version. + * + * The SCTP reference implementation is distributed in the hope that it + * will be useful, but WITHOUT ANY WARRANTY; without even the implied + * ************************ + * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. + * See the GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with GNU CC; see the file COPYING. If not, write to + * the Free Software Foundation, 59 Temple Place - Suite 330, + * Boston, MA 02111-1307, USA. + * + * Please send any bug reports or fixes you make to the + * email address(es): + * lksctp developers <lksctp-developers@lists.sourceforge.net> + * + * Or submit a bug report through the following website: + * http://www.sf.net/projects/lksctp + * + * Written or modified by: + * La Monte H.P. Yarroll <piggy@acm.org> + * Narasimha Budihal <narsi@refcode.org> + * Karl Knutson <karl@athena.chicago.il.us> + * Jon Grimm <jgrimm@us.ibm.com> + * Xingang Guo <xingang.guo@intel.com> + * Daisy Chang <daisyc@us.ibm.com> + * Sridhar Samudrala <samudrala@us.ibm.com> + * Inaky Perez-Gonzalez <inaky.gonzalez@intel.com> + * Ardelle Fan <ardelle.fan@intel.com> + * Ryan Layer <rmlayer@us.ibm.com> + * Anup Pemmaiah <pemmaiah@cc.usu.edu> + * Kevin Gao <kevin.gao@intel.com> + * + * Any bugs reported given to us we will try to fix... any fixes shared will + * be incorporated into the next SCTP release. + */ + +#include <linux/config.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/wait.h> +#include <linux/time.h> +#include <linux/ip.h> +#include <linux/fcntl.h> +#include <linux/poll.h> +#include <linux/init.h> +#include <linux/crypto.h> + +#include <net/ip.h> +#include <net/icmp.h> +#include <net/route.h> +#include <net/ipv6.h> +#include <net/inet_common.h> + +#include <linux/socket.h> /* for sa_family_t */ +#include <net/sock.h> +#include <net/sctp/sctp.h> +#include <net/sctp/sm.h> + +/* 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 kmem_cache_t *sctp_bucket_cachep; + +/* Get the sndbuf space available at the time on the association. */ +static inline int sctp_wspace(struct sctp_association *asoc) +{ + struct sock *sk = asoc->base.sk; + int amt = 0; + + amt = sk->sk_sndbuf - asoc->sndbuf_used; + if (amt < 0) + amt = 0; + 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); + + 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); + sk->sk_wmem_queued += SCTP_DATA_SNDSIZE(chunk); +} + +/* 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))) + 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; + + laddr->v4.sin_port = ntohs(laddr->v4.sin_port); + addr_asoc = sctp_endpoint_lookup_assoc(sctp_sk(sk)->ep, + (union sctp_addr *)addr, + &transport); + laddr->v4.sin_port = htons(laddr->v4.sin_port); + + 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 *uaddr, int addr_len) +{ + int retval = 0; + + sctp_lock_sock(sk); + + SCTP_DEBUG_PRINTK("sctp_bind(sk: %p, uaddr: %p, addr_len: %d)\n", + sk, uaddr, addr_len); + + /* Disallow binding twice. */ + if (!sctp_sk(sk)->ep->base.bind_addr.port) + retval = sctp_do_bind(sk, (union sctp_addr *)uaddr, + 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; + + /* 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; + + SCTP_DEBUG_PRINTK("sctp_do_bind(sk: %p, newaddr: %p, len: %d)\n", + sk, addr, len); + + /* Common sockaddr verification. */ + af = sctp_sockaddr_af(sp, addr, len); + if (!af) + return -EINVAL; + + /* PF specific bind() address verification. */ + if (!sp->pf->bind_verify(sp, addr)) + return -EADDRNOTAVAIL; + + snum= ntohs(addr->v4.sin_port); + + SCTP_DEBUG_PRINTK("sctp_do_bind: port: %d, new port: %d\n", + bp->port, snum); + + /* We must either be unbound, or bind to the same port. */ + if (bp->port && (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; + + /* Make sure we are allowed to bind here. + * The function sctp_get_port_local() does duplicate address + * detection. + */ + if ((ret = sctp_get_port_local(sk, addr))) { + if (ret == (long) sk) { + /* This endpoint has a conflicting address. */ + return -EINVAL; + } else { + return -EADDRINUSE; + } + } + + /* Refresh ephemeral port. */ + if (!bp->port) + bp->port = inet_sk(sk)->num; + + /* Add the address to the bind address list. */ + sctp_local_bh_disable(); + sctp_write_lock(&ep->base.addr_lock); + + /* Use GFP_ATOMIC since BHs are disabled. */ + addr->v4.sin_port = ntohs(addr->v4.sin_port); + ret = sctp_add_bind_addr(bp, addr, GFP_ATOMIC); + addr->v4.sin_port = htons(addr->v4.sin_port); + sctp_write_unlock(&ep->base.addr_lock); + sctp_local_bh_enable(); + + /* Copy back into socket for getsockname() use. */ + if (!ret) { + inet_sk(sk)->sport = htons(inet_sk(sk)->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) +{ + int retval = 0; + + /* If there is an outstanding ASCONF chunk, queue it for later + * transmission. + */ + if (asoc->addip_last_asconf) { + __skb_queue_tail(&asoc->addip_chunks, (struct sk_buff *)chunk); + goto out; + } + + /* Hold the chunk until an ASCONF_ACK is received. */ + sctp_chunk_hold(chunk); + retval = sctp_primitive_ASCONF(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. + */ +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 = (struct sockaddr *)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 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; + void *addr_buf; + struct sctp_af *af; + struct list_head *pos; + struct list_head *p; + int i; + int retval = 0; + + if (!sctp_addip_enable) + return retval; + + sp = sctp_sk(sk); + ep = sp->ep; + + SCTP_DEBUG_PRINTK("%s: (sk: %p, addrs: %p, addrcnt: %d)\n", + __FUNCTION__, sk, addrs, addrcnt); + + list_for_each(pos, &ep->asocs) { + asoc = list_entry(pos, struct sctp_association, 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 = (union sctp_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 address in bind addr list of association as + * Address Parameter of ASCONF CHUNK. + */ + sctp_read_lock(&asoc->base.addr_lock); + bp = &asoc->base.bind_addr; + p = bp->address_list.next; + laddr = list_entry(p, struct sctp_sockaddr_entry, list); + sctp_read_unlock(&asoc->base.addr_lock); + + chunk = sctp_make_asconf_update_ip(asoc, &laddr->a, addrs, + addrcnt, SCTP_PARAM_ADD_IP); + if (!chunk) { + retval = -ENOMEM; + goto out; + } + + retval = sctp_send_asconf(asoc, chunk); + + /* FIXME: After sending the add address ASCONF chunk, we + * cannot append the address to the association's binding + * address list, because the new address may be used as the + * source of a message sent to the peer before the ASCONF + * chunk is received by the peer. So we should wait until + * ASCONF_ACK is received. + */ + } + +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. + */ +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; + union sctp_addr saveaddr; + void *addr_buf; + struct sockaddr *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; + } + + /* The list may contain either IPv4 or IPv6 address; + * determine the address length to copy the address to + * saveaddr. + */ + sa_addr = (struct sockaddr *)addr_buf; + af = sctp_get_af_specific(sa_addr->sa_family); + if (!af) { + retval = -EINVAL; + goto err_bindx_rem; + } + memcpy(&saveaddr, sa_addr, af->sockaddr_len); + saveaddr.v4.sin_port = ntohs(saveaddr.v4.sin_port); + if (saveaddr.v4.sin_port != bp->port) { + retval = -EINVAL; + goto err_bindx_rem; + } + + /* 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 + */ + sctp_local_bh_disable(); + sctp_write_lock(&ep->base.addr_lock); + + retval = sctp_del_bind_addr(bp, &saveaddr); + + sctp_write_unlock(&ep->base.addr_lock); + sctp_local_bh_enable(); + + 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 sctp_sock *sp; + struct sctp_endpoint *ep; + struct sctp_association *asoc; + struct sctp_bind_addr *bp; + struct sctp_chunk *chunk; + union sctp_addr *laddr; + void *addr_buf; + struct sctp_af *af; + struct list_head *pos; + int i; + int retval = 0; + + if (!sctp_addip_enable) + return retval; + + sp = sctp_sk(sk); + ep = sp->ep; + + SCTP_DEBUG_PRINTK("%s: (sk: %p, addrs: %p, addrcnt: %d)\n", + __FUNCTION__, sk, addrs, addrcnt); + + list_for_each(pos, &ep->asocs) { + asoc = list_entry(pos, struct sctp_association, 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 = (union sctp_addr *)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. + */ + sctp_read_lock(&asoc->base.addr_lock); + bp = &asoc->base.bind_addr; + laddr = sctp_find_unmatch_addr(bp, (union sctp_addr *)addrs, + addrcnt, sp); + sctp_read_unlock(&asoc->base.addr_lock); + if (!laddr) + continue; + + chunk = sctp_make_asconf_update_ip(asoc, laddr, addrs, addrcnt, + SCTP_PARAM_DEL_IP); + if (!chunk) { + retval = -ENOMEM; + goto out; + } + + retval = sctp_send_asconf(asoc, chunk); + + /* FIXME: After sending the delete address ASCONF chunk, we + * cannot remove the addresses from the association's bind + * address list, because there maybe some packet send to + * the delete addresses, so we should wait until ASCONF_ACK + * packet is received. + */ + } +out: + return retval; +} + +/* 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 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_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_setsocktopt_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 = (struct sockaddr *)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) { + sa_addr = (struct sockaddr *)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; +} + +/* 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 sctp_endpoint *ep; + struct sctp_association *asoc; + struct list_head *pos, *temp; + + SCTP_DEBUG_PRINTK("sctp_close(sk: 0x%p, timeout:%ld)\n", sk, timeout); + + sctp_lock_sock(sk); + sk->sk_shutdown = SHUTDOWN_MASK; + + ep = sctp_sk(sk)->ep; + + /* Walk all associations on a socket, not 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); + + } else if (sock_flag(sk, SOCK_LINGER) && + !sk->sk_lingertime) + sctp_primitive_ABORT(asoc, NULL); + else + sctp_primitive_SHUTDOWN(asoc, NULL); + } else + sctp_primitive_SHUTDOWN(asoc, NULL); + } + + /* Clean up any skbs sitting on the receive queue. */ + sctp_queue_purge_ulpevents(&sk->sk_receive_queue); + sctp_queue_purge_ulpevents(&sctp_sk(sk)->pd_lobby); + + /* 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 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 = { 0 }; + 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; + struct list_head *pos; + 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: %s.\n", ep->debug_name); + + /* 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); + m |