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socket.c
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socket.c
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/* 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, see
* <http://www.gnu.org/licenses/>.
*
* Please send any bug reports or fixes you make to the
* email address(es):
* lksctp developers <[email protected]>
*
* Written or modified by:
* La Monte H.P. Yarroll <[email protected]>
* Narasimha Budihal <[email protected]>
* Karl Knutson <[email protected]>
* Jon Grimm <[email protected]>
* Xingang Guo <[email protected]>
* Daisy Chang <[email protected]>
* Sridhar Samudrala <[email protected]>
* Inaky Perez-Gonzalez <[email protected]>
* Ardelle Fan <[email protected]>
* Ryan Layer <[email protected]>
* Anup Pemmaiah <[email protected]>
* Kevin Gao <[email protected]>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <crypto/hash.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/wait.h>
#include <linux/time.h>
#include <linux/sched/signal.h>
#include <linux/ip.h>
#include <linux/capability.h>
#include <linux/fcntl.h>
#include <linux/poll.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/file.h>
#include <linux/compat.h>
#include <net/ip.h>
#include <net/icmp.h>
#include <net/route.h>
#include <net/ipv6.h>
#include <net/inet_common.h>
#include <net/busy_poll.h>
#include <linux/socket.h> /* for sa_family_t */
#include <linux/export.h>
#include <net/sock.h>
#include <net/sctp/sctp.h>
#include <net/sctp/sm.h>
#include <net/sctp/stream_sched.h>
/* 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 *asoc, long *timeo_p,
size_t msg_len, struct sock **orig_sk);
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 void sctp_destruct_sock(struct sock *sk);
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 *oldsk, struct sock *newsk,
struct sctp_association *assoc,
enum sctp_socket_type type);
static unsigned long 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. */
skb_shinfo(chunk->skb)->destructor_arg = chunk;
asoc->sndbuf_used += SCTP_DATA_SNDSIZE(chunk) +
sizeof(struct sk_buff) +
sizeof(struct sctp_chunk);
refcount_add(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
sk->sk_wmem_queued += chunk->skb->truesize;
sk_mem_charge(sk, chunk->skb->truesize);
}
static void sctp_clear_owner_w(struct sctp_chunk *chunk)
{
skb_orphan(chunk->skb);
}
static void sctp_for_each_tx_datachunk(struct sctp_association *asoc,
void (*cb)(struct sctp_chunk *))
{
struct sctp_outq *q = &asoc->outqueue;
struct sctp_transport *t;
struct sctp_chunk *chunk;
list_for_each_entry(t, &asoc->peer.transport_addr_list, transports)
list_for_each_entry(chunk, &t->transmitted, transmitted_list)
cb(chunk);
list_for_each_entry(chunk, &q->retransmit, transmitted_list)
cb(chunk);
list_for_each_entry(chunk, &q->sacked, transmitted_list)
cb(chunk);
list_for_each_entry(chunk, &q->abandoned, transmitted_list)
cb(chunk);
list_for_each_entry(chunk, &q->out_chunk_list, list)
cb(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), 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) && !sctp_sstate(sk, CLOSING))
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_af *af = sctp_get_af_specific(addr->ss_family);
union sctp_addr *laddr = (union sctp_addr *)addr;
struct sctp_transport *transport;
if (!af || sctp_verify_addr(sk, laddr, af->sockaddr_len))
return NULL;
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_to_user(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.
*/
static int sctp_bind(struct sock *sk, struct sockaddr *addr, int addr_len)
{
int retval = 0;
lock_sock(sk);
pr_debug("%s: sk:%p, addr:%p, addr_len:%d\n", __func__, 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;
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. */
static int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len)
{
struct net *net = sock_net(sk);
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) {
pr_debug("%s: sk:%p, newaddr:%p, len:%d EINVAL\n",
__func__, sk, addr, len);
return -EINVAL;
}
snum = ntohs(addr->v4.sin_port);
pr_debug("%s: sk:%p, new addr:%pISc, port:%d, new port:%d, len:%d\n",
__func__, sk, &addr->sa, 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) {
pr_debug("%s: new port %d doesn't match existing port "
"%d\n", __func__, snum, bp->port);
return -EINVAL;
}
}
if (snum && snum < inet_prot_sock(net) &&
!ns_capable(net->user_ns, 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, af->sockaddr_len,
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);
sp->pf->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;
pr_debug("%s: sk:%p, addrs:%p, addrcnt:%d\n", __func__, 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;
pr_debug("%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,
sizeof(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 */
sctp_transport_dst_release(trans);
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;
sctp_max_rto(asoc, trans);
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;
pr_debug("%s: sk:%p, addrs:%p, addrcnt:%d\n",
__func__, 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;
pr_debug("%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;
}
pr_debug("%s: keep the last address asoc:%p %pISc at %p\n",
__func__, asoc, &asoc->asconf_addr_del_pending->sa,
asoc->asconf_addr_del_pending);
asoc->src_out_of_asoc_ok = 1;
stored = 1;
goto skip_mkasconf;
}
if (laddr == NULL)
return -EINVAL;
/* 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) {
sctp_transport_dst_release(transport);
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.
*/
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;