freebsd-skq/sys/netinet/sctp_bsd_addr.c

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/*-
* Copyright (c) 2001-2007, by Cisco Systems, Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* a) Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* b) Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the distribution.
*
* c) Neither the name of Cisco Systems, Inc. nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
/* $KAME: sctp_output.c,v 1.46 2005/03/06 16:04:17 itojun Exp $ */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <netinet/sctp_os.h>
#include <netinet/sctp_var.h>
#include <netinet/sctp_pcb.h>
#include <netinet/sctp_header.h>
#include <netinet/sctputil.h>
#include <netinet/sctp_output.h>
#include <netinet/sctp_bsd_addr.h>
#include <netinet/sctp_uio.h>
#include <netinet/sctputil.h>
#include <netinet/sctp_timer.h>
#include <netinet/sctp_asconf.h>
#include <netinet/sctp_sysctl.h>
#include <netinet/sctp_indata.h>
#include <sys/unistd.h>
/* Declare all of our malloc named types */
MALLOC_DEFINE(SCTP_M_MAP, "sctp_map", "sctp asoc map descriptor");
MALLOC_DEFINE(SCTP_M_STRMI, "sctp_stri", "sctp stream in array");
MALLOC_DEFINE(SCTP_M_STRMO, "sctp_stro", "sctp stream out array");
MALLOC_DEFINE(SCTP_M_ASC_ADDR, "sctp_aadr", "sctp asconf address");
MALLOC_DEFINE(SCTP_M_ASC_IT, "sctp_a_it", "sctp asconf iterator");
MALLOC_DEFINE(SCTP_M_AUTH_CL, "sctp_atcl", "sctp auth chunklist");
MALLOC_DEFINE(SCTP_M_AUTH_KY, "sctp_atky", "sctp auth key");
MALLOC_DEFINE(SCTP_M_AUTH_HL, "sctp_athm", "sctp auth hmac list");
MALLOC_DEFINE(SCTP_M_AUTH_IF, "sctp_athi", "sctp auth info");
MALLOC_DEFINE(SCTP_M_STRESET, "sctp_stre", "sctp stream reset");
MALLOC_DEFINE(SCTP_M_CMSG, "sctp_cmsg", "sctp CMSG buffer");
MALLOC_DEFINE(SCTP_M_COPYAL, "sctp_cpal", "sctp copy all");
MALLOC_DEFINE(SCTP_M_VRF, "sctp_vrf", "sctp vrf struct");
MALLOC_DEFINE(SCTP_M_IFA, "sctp_ifa", "sctp ifa struct");
MALLOC_DEFINE(SCTP_M_IFN, "sctp_ifn", "sctp ifn struct");
MALLOC_DEFINE(SCTP_M_TIMW, "sctp_timw", "sctp time block");
MALLOC_DEFINE(SCTP_M_MVRF, "sctp_mvrf", "sctp mvrf pcb list");
MALLOC_DEFINE(SCTP_M_ITER, "sctp_iter", "sctp iterator control");
MALLOC_DEFINE(SCTP_M_SOCKOPT, "sctp_socko", "sctp socket option");
/* Global NON-VNET structure that controls the iterator */
struct iterator_control sctp_it_ctl;
static int __sctp_thread_based_iterator_started = 0;
static void
sctp_cleanup_itqueue(void)
{
struct sctp_iterator *it;
while ((it = TAILQ_FIRST(&sctp_it_ctl.iteratorhead)) != NULL) {
if (it->function_atend != NULL) {
(*it->function_atend) (it->pointer, it->val);
}
TAILQ_REMOVE(&sctp_it_ctl.iteratorhead, it, sctp_nxt_itr);
SCTP_FREE(it, SCTP_M_ITER);
}
}
void
sctp_wakeup_iterator(void)
{
wakeup(&sctp_it_ctl.iterator_running);
}
static void
sctp_iterator_thread(void *v)
{
SCTP_IPI_ITERATOR_WQ_LOCK();
while (1) {
msleep(&sctp_it_ctl.iterator_running,
&sctp_it_ctl.ipi_iterator_wq_mtx,
0, "waiting_for_work", 0);
if (sctp_it_ctl.iterator_flags & SCTP_ITERATOR_MUST_EXIT) {
SCTP_IPI_ITERATOR_WQ_DESTROY();
SCTP_ITERATOR_LOCK_DESTROY();
sctp_cleanup_itqueue();
__sctp_thread_based_iterator_started = 0;
2008-08-09 11:28:57 +00:00
kthread_exit();
}
sctp_iterator_worker();
}
}
void
sctp_startup_iterator(void)
{
if (__sctp_thread_based_iterator_started) {
/* You only get one */
return;
}
/* init the iterator head */
__sctp_thread_based_iterator_started = 1;
sctp_it_ctl.iterator_running = 0;
sctp_it_ctl.iterator_flags = 0;
sctp_it_ctl.cur_it = NULL;
SCTP_ITERATOR_LOCK_INIT();
SCTP_IPI_ITERATOR_WQ_INIT();
TAILQ_INIT(&sctp_it_ctl.iteratorhead);
int ret;
ret = kproc_create(sctp_iterator_thread,
(void *)NULL,
&sctp_it_ctl.thread_proc,
RFPROC,
SCTP_KTHREAD_PAGES,
SCTP_KTRHEAD_NAME);
}
#ifdef INET6
void
sctp_gather_internal_ifa_flags(struct sctp_ifa *ifa)
{
struct in6_ifaddr *ifa6;
ifa6 = (struct in6_ifaddr *)ifa->ifa;
ifa->flags = ifa6->ia6_flags;
2009-09-17 15:11:12 +00:00
if (!MODULE_GLOBAL(ip6_use_deprecated)) {
if (ifa->flags &
IN6_IFF_DEPRECATED) {
ifa->localifa_flags |= SCTP_ADDR_IFA_UNUSEABLE;
} else {
ifa->localifa_flags &= ~SCTP_ADDR_IFA_UNUSEABLE;
}
} else {
ifa->localifa_flags &= ~SCTP_ADDR_IFA_UNUSEABLE;
}
if (ifa->flags &
(IN6_IFF_DETACHED |
IN6_IFF_ANYCAST |
IN6_IFF_NOTREADY)) {
ifa->localifa_flags |= SCTP_ADDR_IFA_UNUSEABLE;
} else {
ifa->localifa_flags &= ~SCTP_ADDR_IFA_UNUSEABLE;
}
}
#endif /* INET6 */
static uint32_t
sctp_is_desired_interface_type(struct ifaddr *ifa)
{
int result;
/* check the interface type to see if it's one we care about */
switch (ifa->ifa_ifp->if_type) {
case IFT_ETHER:
case IFT_ISO88023:
case IFT_ISO88024:
case IFT_ISO88025:
case IFT_ISO88026:
case IFT_STARLAN:
case IFT_P10:
case IFT_P80:
case IFT_HY:
case IFT_FDDI:
case IFT_XETHER:
case IFT_ISDNBASIC:
case IFT_ISDNPRIMARY:
case IFT_PTPSERIAL:
- send call has a reference to uio->uio_resid in the recent send code, but uio may be NULL on sendfile calls. Change to use sndlen variable. - EMSGSIZE is not being returned in non-blocking mode and needs a small tweak to look if the msg would ever fit when returning EWOULDBLOCK. - FWD-TSN has a bug in stream processing which could cause a panic. This is a follow on to the codenomicon fix. - PDAPI level 1 and 2 do not work unless the reader gets his returned buffer full. Fix so we can break out when at level 1 or 2. - Fix fast-handoff features to copy across properly on accepted sockets - Fix sctp_peeloff() system call when no true system call exists to screen arguments for errors. In cases where a real system call exists the system call itself does this. - Fix raddr leak in recent add-ip code change for bundled asconfs (even when non-bundled asconfs are received) - Make sure ipi_addr lock is held when walking global addr list. Need to change this lock type to a rwlock(). - Add don't wake flag on both input and output when the socket is closing. - When deleting an address verify the interface is correct before allowing the delete to process. This protects panda and unnumbered. - Clean up old sysctl stuff and get rid of the old Open/Net BSD structures. - Add a function to watch the ranges in the sysctl sets. - When appending in the reassembly queue, validate that the assoc has not gone to about to be freed. If so (in the middle) abort out. Note this especially effects MAC I think due to the lock/unlock they do (or with LOCK testing in place). - Netstat patch to get rid of warnings. - Make sure that no data gets queued to inactive/unconfirmed destinations. This especially effect CMT but also makes a impact on regular SCTP as well. - During init collision when we detect seq number out of sync we need to treat it like Case C and discard the cookie (no invarient needed here). - Atomic access to the random store. - When we declare a vtag good, we need to shove it into the time wait hash to prevent further use. When the tag is put into the assoc hash, we need to remove it from the twait hash (where it will surely be). This prevents duplicate tag assignments. - Move decr-ref count to better protect sysctl out of data. - ltrace error corrections in sctp6_usrreq.c - Add hook for interface up/down to be sent to us. - Make sysctl() exported structures independent of processor architecture. - Fix route and src addr cache clearing for delete address case. - Make sure address marked SCTP_DEL_IP_ADDRESS is never selected as src addr. - in icmp handling fixed so we actually look at the icmp codes to figure out what to do. - Modified mobility code. Reception of DELETE IP ADDRESS for a primary destination and SET PRIMARY for a new primary destination is used for retransmission trigger to the new primary destination. Also, in this case, destination of chunks in send_queue are changed to the new primary destination. - Fix so that we disallow sending by mbuf to ever have EEOR mode set upon it. Approved by: re@freebsd.org (B Mah)
2007-09-08 17:48:46 +00:00
case IFT_OTHER:
case IFT_PPP:
case IFT_LOOP:
case IFT_SLIP:
case IFT_GIF:
case IFT_L2VLAN:
case IFT_IP:
case IFT_IPOVERCDLC:
case IFT_IPOVERCLAW:
case IFT_VIRTUALIPADDRESS:
result = 1;
break;
default:
result = 0;
}
return (result);
}
static void
sctp_init_ifns_for_vrf(int vrfid)
{
/*
* Here we must apply ANY locks needed by the IFN we access and also
* make sure we lock any IFA that exists as we float through the
* list of IFA's
*/
struct ifnet *ifn;
struct ifaddr *ifa;
struct in6_ifaddr *ifa6;
struct sctp_ifa *sctp_ifa;
uint32_t ifa_flags;
IFNET_RLOCK();
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TAILQ_FOREACH(ifn, &MODULE_GLOBAL(ifnet), if_list) {
IF_ADDR_LOCK(ifn);
TAILQ_FOREACH(ifa, &ifn->if_addrlist, ifa_list) {
if (ifa->ifa_addr == NULL) {
continue;
}
if ((ifa->ifa_addr->sa_family != AF_INET) && (ifa->ifa_addr->sa_family != AF_INET6)) {
/* non inet/inet6 skip */
continue;
}
if (ifa->ifa_addr->sa_family == AF_INET6) {
if (IN6_IS_ADDR_UNSPECIFIED(&((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr)) {
/* skip unspecifed addresses */
continue;
}
} else {
if (((struct sockaddr_in *)ifa->ifa_addr)->sin_addr.s_addr == 0) {
continue;
}
}
if (sctp_is_desired_interface_type(ifa) == 0) {
/* non desired type */
continue;
}
if (ifa->ifa_addr->sa_family == AF_INET6) {
ifa6 = (struct in6_ifaddr *)ifa;
ifa_flags = ifa6->ia6_flags;
} else {
ifa_flags = 0;
}
sctp_ifa = sctp_add_addr_to_vrf(vrfid,
(void *)ifn,
ifn->if_index,
ifn->if_type,
ifn->if_xname,
(void *)ifa,
ifa->ifa_addr,
ifa_flags,
0);
if (sctp_ifa) {
sctp_ifa->localifa_flags &= ~SCTP_ADDR_DEFER_USE;
}
}
IF_ADDR_UNLOCK(ifn);
}
IFNET_RUNLOCK();
}
void
sctp_init_vrf_list(int vrfid)
{
if (vrfid > SCTP_MAX_VRF_ID)
/* can't do that */
return;
/* Don't care about return here */
(void)sctp_allocate_vrf(vrfid);
/*
* Now we need to build all the ifn's for this vrf and there
* addresses
*/
sctp_init_ifns_for_vrf(vrfid);
}
void
sctp_addr_change(struct ifaddr *ifa, int cmd)
{
struct sctp_ifa *ifap = NULL;
uint32_t ifa_flags = 0;
/*
* BSD only has one VRF, if this changes we will need to hook in the
* right things here to get the id to pass to the address managment
* routine.
*/
if (SCTP_BASE_VAR(first_time) == 0) {
/* Special test to see if my ::1 will showup with this */
SCTP_BASE_VAR(first_time) = 1;
sctp_init_ifns_for_vrf(SCTP_DEFAULT_VRFID);
}
if ((cmd != RTM_ADD) && (cmd != RTM_DELETE)) {
/* don't know what to do with this */
return;
}
if (ifa->ifa_addr == NULL) {
return;
}
if ((ifa->ifa_addr->sa_family != AF_INET) && (ifa->ifa_addr->sa_family != AF_INET6)) {
/* non inet/inet6 skip */
return;
}
if (ifa->ifa_addr->sa_family == AF_INET6) {
ifa_flags = ((struct in6_ifaddr *)ifa)->ia6_flags;
if (IN6_IS_ADDR_UNSPECIFIED(&((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr)) {
/* skip unspecifed addresses */
return;
}
} else {
if (((struct sockaddr_in *)ifa->ifa_addr)->sin_addr.s_addr == 0) {
return;
}
}
if (sctp_is_desired_interface_type(ifa) == 0) {
/* non desired type */
return;
}
if (cmd == RTM_ADD) {
ifap = sctp_add_addr_to_vrf(SCTP_DEFAULT_VRFID, (void *)ifa->ifa_ifp,
ifa->ifa_ifp->if_index, ifa->ifa_ifp->if_type,
ifa->ifa_ifp->if_xname,
(void *)ifa, ifa->ifa_addr, ifa_flags, 1);
} else {
- send call has a reference to uio->uio_resid in the recent send code, but uio may be NULL on sendfile calls. Change to use sndlen variable. - EMSGSIZE is not being returned in non-blocking mode and needs a small tweak to look if the msg would ever fit when returning EWOULDBLOCK. - FWD-TSN has a bug in stream processing which could cause a panic. This is a follow on to the codenomicon fix. - PDAPI level 1 and 2 do not work unless the reader gets his returned buffer full. Fix so we can break out when at level 1 or 2. - Fix fast-handoff features to copy across properly on accepted sockets - Fix sctp_peeloff() system call when no true system call exists to screen arguments for errors. In cases where a real system call exists the system call itself does this. - Fix raddr leak in recent add-ip code change for bundled asconfs (even when non-bundled asconfs are received) - Make sure ipi_addr lock is held when walking global addr list. Need to change this lock type to a rwlock(). - Add don't wake flag on both input and output when the socket is closing. - When deleting an address verify the interface is correct before allowing the delete to process. This protects panda and unnumbered. - Clean up old sysctl stuff and get rid of the old Open/Net BSD structures. - Add a function to watch the ranges in the sysctl sets. - When appending in the reassembly queue, validate that the assoc has not gone to about to be freed. If so (in the middle) abort out. Note this especially effects MAC I think due to the lock/unlock they do (or with LOCK testing in place). - Netstat patch to get rid of warnings. - Make sure that no data gets queued to inactive/unconfirmed destinations. This especially effect CMT but also makes a impact on regular SCTP as well. - During init collision when we detect seq number out of sync we need to treat it like Case C and discard the cookie (no invarient needed here). - Atomic access to the random store. - When we declare a vtag good, we need to shove it into the time wait hash to prevent further use. When the tag is put into the assoc hash, we need to remove it from the twait hash (where it will surely be). This prevents duplicate tag assignments. - Move decr-ref count to better protect sysctl out of data. - ltrace error corrections in sctp6_usrreq.c - Add hook for interface up/down to be sent to us. - Make sysctl() exported structures independent of processor architecture. - Fix route and src addr cache clearing for delete address case. - Make sure address marked SCTP_DEL_IP_ADDRESS is never selected as src addr. - in icmp handling fixed so we actually look at the icmp codes to figure out what to do. - Modified mobility code. Reception of DELETE IP ADDRESS for a primary destination and SET PRIMARY for a new primary destination is used for retransmission trigger to the new primary destination. Also, in this case, destination of chunks in send_queue are changed to the new primary destination. - Fix so that we disallow sending by mbuf to ever have EEOR mode set upon it. Approved by: re@freebsd.org (B Mah)
2007-09-08 17:48:46 +00:00
sctp_del_addr_from_vrf(SCTP_DEFAULT_VRFID, ifa->ifa_addr,
ifa->ifa_ifp->if_index,
ifa->ifa_ifp->if_xname
);
/*
* We don't bump refcount here so when it completes the
* final delete will happen.
*/
}
}
void
sctp_add_or_del_interfaces(int (*pred) (struct ifnet *), int add){
struct ifnet *ifn;
struct ifaddr *ifa;
IFNET_RLOCK();
2009-09-17 15:11:12 +00:00
TAILQ_FOREACH(ifn, &MODULE_GLOBAL(ifnet), if_list) {
if (!(*pred) (ifn)) {
continue;
}
TAILQ_FOREACH(ifa, &ifn->if_addrlist, ifa_list) {
sctp_addr_change(ifa, add ? RTM_ADD : RTM_DELETE);
}
}
IFNET_RUNLOCK();
}
struct mbuf *
sctp_get_mbuf_for_msg(unsigned int space_needed, int want_header,
int how, int allonebuf, int type)
{
struct mbuf *m = NULL;
m = m_getm2(NULL, space_needed, how, type, want_header ? M_PKTHDR : 0);
if (m == NULL) {
/* bad, no memory */
return (m);
}
if (allonebuf) {
int siz;
if (SCTP_BUF_IS_EXTENDED(m)) {
siz = SCTP_BUF_EXTEND_SIZE(m);
} else {
if (want_header)
siz = MHLEN;
else
siz = MLEN;
}
if (siz < space_needed) {
m_freem(m);
return (NULL);
}
}
if (SCTP_BUF_NEXT(m)) {
sctp_m_freem(SCTP_BUF_NEXT(m));
SCTP_BUF_NEXT(m) = NULL;
}
#ifdef SCTP_MBUF_LOGGING
if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_MBUF_LOGGING_ENABLE) {
if (SCTP_BUF_IS_EXTENDED(m)) {
sctp_log_mb(m, SCTP_MBUF_IALLOC);
}
}
#endif
return (m);
}
#ifdef SCTP_PACKET_LOGGING
void
sctp_packet_log(struct mbuf *m, int length)
{
int *lenat, thisone;
void *copyto;
uint32_t *tick_tock;
int total_len;
int grabbed_lock = 0;
int value, newval, thisend, thisbegin;
/*
* Buffer layout. -sizeof this entry (total_len) -previous end
* (value) -ticks of log (ticks) o -ip packet o -as logged -
* where this started (thisbegin) x <--end points here
*/
total_len = SCTP_SIZE32((length + (4 * sizeof(int))));
/* Log a packet to the buffer. */
if (total_len > SCTP_PACKET_LOG_SIZE) {
/* Can't log this packet I have not a buffer big enough */
return;
}
if (length < (int)(SCTP_MIN_V4_OVERHEAD + sizeof(struct sctp_cookie_ack_chunk))) {
return;
}
atomic_add_int(&SCTP_BASE_VAR(packet_log_writers), 1);
try_again:
if (SCTP_BASE_VAR(packet_log_writers) > SCTP_PKTLOG_WRITERS_NEED_LOCK) {
SCTP_IP_PKTLOG_LOCK();
grabbed_lock = 1;
again_locked:
value = SCTP_BASE_VAR(packet_log_end);
newval = SCTP_BASE_VAR(packet_log_end) + total_len;
if (newval >= SCTP_PACKET_LOG_SIZE) {
/* we wrapped */
thisbegin = 0;
thisend = total_len;
} else {
thisbegin = SCTP_BASE_VAR(packet_log_end);
thisend = newval;
}
if (!(atomic_cmpset_int(&SCTP_BASE_VAR(packet_log_end), value, thisend))) {
goto again_locked;
}
} else {
value = SCTP_BASE_VAR(packet_log_end);
newval = SCTP_BASE_VAR(packet_log_end) + total_len;
if (newval >= SCTP_PACKET_LOG_SIZE) {
/* we wrapped */
thisbegin = 0;
thisend = total_len;
} else {
thisbegin = SCTP_BASE_VAR(packet_log_end);
thisend = newval;
}
if (!(atomic_cmpset_int(&SCTP_BASE_VAR(packet_log_end), value, thisend))) {
goto try_again;
}
}
/* Sanity check */
if (thisend >= SCTP_PACKET_LOG_SIZE) {
printf("Insanity stops a log thisbegin:%d thisend:%d writers:%d lock:%d end:%d\n",
thisbegin,
thisend,
SCTP_BASE_VAR(packet_log_writers),
grabbed_lock,
SCTP_BASE_VAR(packet_log_end));
SCTP_BASE_VAR(packet_log_end) = 0;
goto no_log;
}
lenat = (int *)&SCTP_BASE_VAR(packet_log_buffer)[thisbegin];
*lenat = total_len;
lenat++;
*lenat = value;
lenat++;
tick_tock = (uint32_t *) lenat;
lenat++;
*tick_tock = sctp_get_tick_count();
copyto = (void *)lenat;
thisone = thisend - sizeof(int);
lenat = (int *)&SCTP_BASE_VAR(packet_log_buffer)[thisone];
*lenat = thisbegin;
if (grabbed_lock) {
SCTP_IP_PKTLOG_UNLOCK();
grabbed_lock = 0;
}
m_copydata(m, 0, length, (caddr_t)copyto);
no_log:
if (grabbed_lock) {
SCTP_IP_PKTLOG_UNLOCK();
}
atomic_subtract_int(&SCTP_BASE_VAR(packet_log_writers), 1);
}
int
sctp_copy_out_packet_log(uint8_t * target, int length)
{
/*
* We wind through the packet log starting at start copying up to
* length bytes out. We return the number of bytes copied.
*/
int tocopy, this_copy;
int *lenat;
int did_delay = 0;
tocopy = length;
if (length < (int)(2 * sizeof(int))) {
/* not enough room */
return (0);
}
if (SCTP_PKTLOG_WRITERS_NEED_LOCK) {
atomic_add_int(&SCTP_BASE_VAR(packet_log_writers), SCTP_PKTLOG_WRITERS_NEED_LOCK);
again:
if ((did_delay == 0) && (SCTP_BASE_VAR(packet_log_writers) != SCTP_PKTLOG_WRITERS_NEED_LOCK)) {
/*
* we delay here for just a moment hoping the
* writer(s) that were present when we entered will
* have left and we only have locking ones that will
* contend with us for the lock. This does not
* assure 100% access, but its good enough for a
* logging facility like this.
*/
did_delay = 1;
DELAY(10);
goto again;
}
}
SCTP_IP_PKTLOG_LOCK();
lenat = (int *)target;
*lenat = SCTP_BASE_VAR(packet_log_end);
lenat++;
this_copy = min((length - sizeof(int)), SCTP_PACKET_LOG_SIZE);
memcpy((void *)lenat, (void *)SCTP_BASE_VAR(packet_log_buffer), this_copy);
if (SCTP_PKTLOG_WRITERS_NEED_LOCK) {
atomic_subtract_int(&SCTP_BASE_VAR(packet_log_writers),
SCTP_PKTLOG_WRITERS_NEED_LOCK);
}
SCTP_IP_PKTLOG_UNLOCK();
return (this_copy + sizeof(int));
}
#endif