The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/netinet/sctp_bsd_addr.c

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    1 /*-
    2  * Copyright (c) 2001-2007, by Cisco Systems, Inc. All rights reserved.
    3  * Copyright (c) 2008-2012, by Randall Stewart. All rights reserved.
    4  * Copyright (c) 2008-2012, by Michael Tuexen. All rights reserved.
    5  *
    6  * Redistribution and use in source and binary forms, with or without
    7  * modification, are permitted provided that the following conditions are met:
    8  *
    9  * a) Redistributions of source code must retain the above copyright notice,
   10  *    this list of conditions and the following disclaimer.
   11  *
   12  * b) Redistributions in binary form must reproduce the above copyright
   13  *    notice, this list of conditions and the following disclaimer in
   14  *    the documentation and/or other materials provided with the distribution.
   15  *
   16  * c) Neither the name of Cisco Systems, Inc. nor the names of its
   17  *    contributors may be used to endorse or promote products derived
   18  *    from this software without specific prior written permission.
   19  *
   20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   21  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
   22  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   23  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
   24  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
   30  * THE POSSIBILITY OF SUCH DAMAGE.
   31  */
   32 
   33 #include <sys/cdefs.h>
   34 __FBSDID("$FreeBSD: releng/10.3/sys/netinet/sctp_bsd_addr.c 296052 2016-02-25 18:46:06Z tuexen $");
   35 
   36 #include <netinet/sctp_os.h>
   37 #include <netinet/sctp_var.h>
   38 #include <netinet/sctp_pcb.h>
   39 #include <netinet/sctp_header.h>
   40 #include <netinet/sctputil.h>
   41 #include <netinet/sctp_output.h>
   42 #include <netinet/sctp_bsd_addr.h>
   43 #include <netinet/sctp_uio.h>
   44 #include <netinet/sctputil.h>
   45 #include <netinet/sctp_timer.h>
   46 #include <netinet/sctp_asconf.h>
   47 #include <netinet/sctp_sysctl.h>
   48 #include <netinet/sctp_indata.h>
   49 #include <sys/unistd.h>
   50 
   51 /* Declare all of our malloc named types */
   52 MALLOC_DEFINE(SCTP_M_MAP, "sctp_map", "sctp asoc map descriptor");
   53 MALLOC_DEFINE(SCTP_M_STRMI, "sctp_stri", "sctp stream in array");
   54 MALLOC_DEFINE(SCTP_M_STRMO, "sctp_stro", "sctp stream out array");
   55 MALLOC_DEFINE(SCTP_M_ASC_ADDR, "sctp_aadr", "sctp asconf address");
   56 MALLOC_DEFINE(SCTP_M_ASC_IT, "sctp_a_it", "sctp asconf iterator");
   57 MALLOC_DEFINE(SCTP_M_AUTH_CL, "sctp_atcl", "sctp auth chunklist");
   58 MALLOC_DEFINE(SCTP_M_AUTH_KY, "sctp_atky", "sctp auth key");
   59 MALLOC_DEFINE(SCTP_M_AUTH_HL, "sctp_athm", "sctp auth hmac list");
   60 MALLOC_DEFINE(SCTP_M_AUTH_IF, "sctp_athi", "sctp auth info");
   61 MALLOC_DEFINE(SCTP_M_STRESET, "sctp_stre", "sctp stream reset");
   62 MALLOC_DEFINE(SCTP_M_CMSG, "sctp_cmsg", "sctp CMSG buffer");
   63 MALLOC_DEFINE(SCTP_M_COPYAL, "sctp_cpal", "sctp copy all");
   64 MALLOC_DEFINE(SCTP_M_VRF, "sctp_vrf", "sctp vrf struct");
   65 MALLOC_DEFINE(SCTP_M_IFA, "sctp_ifa", "sctp ifa struct");
   66 MALLOC_DEFINE(SCTP_M_IFN, "sctp_ifn", "sctp ifn struct");
   67 MALLOC_DEFINE(SCTP_M_TIMW, "sctp_timw", "sctp time block");
   68 MALLOC_DEFINE(SCTP_M_MVRF, "sctp_mvrf", "sctp mvrf pcb list");
   69 MALLOC_DEFINE(SCTP_M_ITER, "sctp_iter", "sctp iterator control");
   70 MALLOC_DEFINE(SCTP_M_SOCKOPT, "sctp_socko", "sctp socket option");
   71 MALLOC_DEFINE(SCTP_M_MCORE, "sctp_mcore", "sctp mcore queue");
   72 
   73 /* Global NON-VNET structure that controls the iterator */
   74 struct iterator_control sctp_it_ctl;
   75 
   76 
   77 void
   78 sctp_wakeup_iterator(void)
   79 {
   80         wakeup(&sctp_it_ctl.iterator_running);
   81 }
   82 
   83 static void
   84 sctp_iterator_thread(void *v SCTP_UNUSED)
   85 {
   86         SCTP_IPI_ITERATOR_WQ_LOCK();
   87         /* In FreeBSD this thread never terminates. */
   88         for (;;) {
   89                 msleep(&sctp_it_ctl.iterator_running,
   90                     &sctp_it_ctl.ipi_iterator_wq_mtx,
   91                     0, "waiting_for_work", 0);
   92                 sctp_iterator_worker();
   93         }
   94 }
   95 
   96 void
   97 sctp_startup_iterator(void)
   98 {
   99         if (sctp_it_ctl.thread_proc) {
  100                 /* You only get one */
  101                 return;
  102         }
  103         /* Initialize global locks here, thus only once. */
  104         SCTP_ITERATOR_LOCK_INIT();
  105         SCTP_IPI_ITERATOR_WQ_INIT();
  106         TAILQ_INIT(&sctp_it_ctl.iteratorhead);
  107         kproc_create(sctp_iterator_thread,
  108             (void *)NULL,
  109             &sctp_it_ctl.thread_proc,
  110             RFPROC,
  111             SCTP_KTHREAD_PAGES,
  112             SCTP_KTRHEAD_NAME);
  113 }
  114 
  115 #ifdef INET6
  116 
  117 void
  118 sctp_gather_internal_ifa_flags(struct sctp_ifa *ifa)
  119 {
  120         struct in6_ifaddr *ifa6;
  121 
  122         ifa6 = (struct in6_ifaddr *)ifa->ifa;
  123         ifa->flags = ifa6->ia6_flags;
  124         if (!MODULE_GLOBAL(ip6_use_deprecated)) {
  125                 if (ifa->flags &
  126                     IN6_IFF_DEPRECATED) {
  127                         ifa->localifa_flags |= SCTP_ADDR_IFA_UNUSEABLE;
  128                 } else {
  129                         ifa->localifa_flags &= ~SCTP_ADDR_IFA_UNUSEABLE;
  130                 }
  131         } else {
  132                 ifa->localifa_flags &= ~SCTP_ADDR_IFA_UNUSEABLE;
  133         }
  134         if (ifa->flags &
  135             (IN6_IFF_DETACHED |
  136             IN6_IFF_ANYCAST |
  137             IN6_IFF_NOTREADY)) {
  138                 ifa->localifa_flags |= SCTP_ADDR_IFA_UNUSEABLE;
  139         } else {
  140                 ifa->localifa_flags &= ~SCTP_ADDR_IFA_UNUSEABLE;
  141         }
  142 }
  143 
  144 #endif                          /* INET6 */
  145 
  146 
  147 static uint32_t
  148 sctp_is_desired_interface_type(struct ifnet *ifn)
  149 {
  150         int result;
  151 
  152         /* check the interface type to see if it's one we care about */
  153         switch (ifn->if_type) {
  154         case IFT_ETHER:
  155         case IFT_ISO88023:
  156         case IFT_ISO88024:
  157         case IFT_ISO88025:
  158         case IFT_ISO88026:
  159         case IFT_STARLAN:
  160         case IFT_P10:
  161         case IFT_P80:
  162         case IFT_HY:
  163         case IFT_FDDI:
  164         case IFT_XETHER:
  165         case IFT_ISDNBASIC:
  166         case IFT_ISDNPRIMARY:
  167         case IFT_PTPSERIAL:
  168         case IFT_OTHER:
  169         case IFT_PPP:
  170         case IFT_LOOP:
  171         case IFT_SLIP:
  172         case IFT_GIF:
  173         case IFT_L2VLAN:
  174         case IFT_STF:
  175         case IFT_IP:
  176         case IFT_IPOVERCDLC:
  177         case IFT_IPOVERCLAW:
  178         case IFT_PROPVIRTUAL:   /* NetGraph Virtual too */
  179         case IFT_VIRTUALIPADDRESS:
  180                 result = 1;
  181                 break;
  182         default:
  183                 result = 0;
  184         }
  185 
  186         return (result);
  187 }
  188 
  189 
  190 
  191 
  192 static void
  193 sctp_init_ifns_for_vrf(int vrfid)
  194 {
  195         /*
  196          * Here we must apply ANY locks needed by the IFN we access and also
  197          * make sure we lock any IFA that exists as we float through the
  198          * list of IFA's
  199          */
  200         struct ifnet *ifn;
  201         struct ifaddr *ifa;
  202         struct sctp_ifa *sctp_ifa;
  203         uint32_t ifa_flags;
  204 
  205 #ifdef INET6
  206         struct in6_ifaddr *ifa6;
  207 
  208 #endif
  209 
  210         IFNET_RLOCK();
  211         TAILQ_FOREACH(ifn, &MODULE_GLOBAL(ifnet), if_list) {
  212                 if (sctp_is_desired_interface_type(ifn) == 0) {
  213                         /* non desired type */
  214                         continue;
  215                 }
  216                 IF_ADDR_RLOCK(ifn);
  217                 TAILQ_FOREACH(ifa, &ifn->if_addrlist, ifa_list) {
  218                         if (ifa->ifa_addr == NULL) {
  219                                 continue;
  220                         }
  221                         switch (ifa->ifa_addr->sa_family) {
  222 #ifdef INET
  223                         case AF_INET:
  224                                 if (((struct sockaddr_in *)ifa->ifa_addr)->sin_addr.s_addr == 0) {
  225                                         continue;
  226                                 }
  227                                 break;
  228 #endif
  229 #ifdef INET6
  230                         case AF_INET6:
  231                                 if (IN6_IS_ADDR_UNSPECIFIED(&((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr)) {
  232                                         /* skip unspecifed addresses */
  233                                         continue;
  234                                 }
  235                                 break;
  236 #endif
  237                         default:
  238                                 continue;
  239                         }
  240                         switch (ifa->ifa_addr->sa_family) {
  241 #ifdef INET
  242                         case AF_INET:
  243                                 ifa_flags = 0;
  244                                 break;
  245 #endif
  246 #ifdef INET6
  247                         case AF_INET6:
  248                                 ifa6 = (struct in6_ifaddr *)ifa;
  249                                 ifa_flags = ifa6->ia6_flags;
  250                                 break;
  251 #endif
  252                         default:
  253                                 ifa_flags = 0;
  254                                 break;
  255                         }
  256                         sctp_ifa = sctp_add_addr_to_vrf(vrfid,
  257                             (void *)ifn,
  258                             ifn->if_index,
  259                             ifn->if_type,
  260                             ifn->if_xname,
  261                             (void *)ifa,
  262                             ifa->ifa_addr,
  263                             ifa_flags,
  264                             0);
  265                         if (sctp_ifa) {
  266                                 sctp_ifa->localifa_flags &= ~SCTP_ADDR_DEFER_USE;
  267                         }
  268                 }
  269                 IF_ADDR_RUNLOCK(ifn);
  270         }
  271         IFNET_RUNLOCK();
  272 }
  273 
  274 void
  275 sctp_init_vrf_list(int vrfid)
  276 {
  277         if (vrfid > SCTP_MAX_VRF_ID)
  278                 /* can't do that */
  279                 return;
  280 
  281         /* Don't care about return here */
  282         (void)sctp_allocate_vrf(vrfid);
  283 
  284         /*
  285          * Now we need to build all the ifn's for this vrf and there
  286          * addresses
  287          */
  288         sctp_init_ifns_for_vrf(vrfid);
  289 }
  290 
  291 void
  292 sctp_addr_change(struct ifaddr *ifa, int cmd)
  293 {
  294         uint32_t ifa_flags = 0;
  295 
  296         if (SCTP_BASE_VAR(sctp_pcb_initialized) == 0) {
  297                 return;
  298         }
  299         /*
  300          * BSD only has one VRF, if this changes we will need to hook in the
  301          * right things here to get the id to pass to the address managment
  302          * routine.
  303          */
  304         if (SCTP_BASE_VAR(first_time) == 0) {
  305                 /* Special test to see if my ::1 will showup with this */
  306                 SCTP_BASE_VAR(first_time) = 1;
  307                 sctp_init_ifns_for_vrf(SCTP_DEFAULT_VRFID);
  308         }
  309         if ((cmd != RTM_ADD) && (cmd != RTM_DELETE)) {
  310                 /* don't know what to do with this */
  311                 return;
  312         }
  313         if (ifa->ifa_addr == NULL) {
  314                 return;
  315         }
  316         if (sctp_is_desired_interface_type(ifa->ifa_ifp) == 0) {
  317                 /* non desired type */
  318                 return;
  319         }
  320         switch (ifa->ifa_addr->sa_family) {
  321 #ifdef INET
  322         case AF_INET:
  323                 if (((struct sockaddr_in *)ifa->ifa_addr)->sin_addr.s_addr == 0) {
  324                         return;
  325                 }
  326                 break;
  327 #endif
  328 #ifdef INET6
  329         case AF_INET6:
  330                 ifa_flags = ((struct in6_ifaddr *)ifa)->ia6_flags;
  331                 if (IN6_IS_ADDR_UNSPECIFIED(&((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr)) {
  332                         /* skip unspecifed addresses */
  333                         return;
  334                 }
  335                 break;
  336 #endif
  337         default:
  338                 /* non inet/inet6 skip */
  339                 return;
  340         }
  341         if (cmd == RTM_ADD) {
  342                 (void)sctp_add_addr_to_vrf(SCTP_DEFAULT_VRFID, (void *)ifa->ifa_ifp,
  343                     ifa->ifa_ifp->if_index, ifa->ifa_ifp->if_type, ifa->ifa_ifp->if_xname,
  344                     (void *)ifa, ifa->ifa_addr, ifa_flags, 1);
  345         } else {
  346 
  347                 sctp_del_addr_from_vrf(SCTP_DEFAULT_VRFID, ifa->ifa_addr,
  348                     ifa->ifa_ifp->if_index,
  349                     ifa->ifa_ifp->if_xname);
  350 
  351                 /*
  352                  * We don't bump refcount here so when it completes the
  353                  * final delete will happen.
  354                  */
  355         }
  356 }
  357 
  358 void
  359      sctp_add_or_del_interfaces(int (*pred) (struct ifnet *), int add){
  360         struct ifnet *ifn;
  361         struct ifaddr *ifa;
  362 
  363         IFNET_RLOCK();
  364         TAILQ_FOREACH(ifn, &MODULE_GLOBAL(ifnet), if_list) {
  365                 if (!(*pred) (ifn)) {
  366                         continue;
  367                 }
  368                 TAILQ_FOREACH(ifa, &ifn->if_addrlist, ifa_list) {
  369                         sctp_addr_change(ifa, add ? RTM_ADD : RTM_DELETE);
  370                 }
  371         }
  372         IFNET_RUNLOCK();
  373 }
  374 
  375 struct mbuf *
  376 sctp_get_mbuf_for_msg(unsigned int space_needed, int want_header,
  377     int how, int allonebuf, int type)
  378 {
  379         struct mbuf *m = NULL;
  380 
  381         m = m_getm2(NULL, space_needed, how, type, want_header ? M_PKTHDR : 0);
  382         if (m == NULL) {
  383                 /* bad, no memory */
  384                 return (m);
  385         }
  386         if (allonebuf) {
  387                 int siz;
  388 
  389                 if (SCTP_BUF_IS_EXTENDED(m)) {
  390                         siz = SCTP_BUF_EXTEND_SIZE(m);
  391                 } else {
  392                         if (want_header)
  393                                 siz = MHLEN;
  394                         else
  395                                 siz = MLEN;
  396                 }
  397                 if (siz < space_needed) {
  398                         m_freem(m);
  399                         return (NULL);
  400                 }
  401         }
  402         if (SCTP_BUF_NEXT(m)) {
  403                 sctp_m_freem(SCTP_BUF_NEXT(m));
  404                 SCTP_BUF_NEXT(m) = NULL;
  405         }
  406 #ifdef SCTP_MBUF_LOGGING
  407         if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_MBUF_LOGGING_ENABLE) {
  408                 sctp_log_mb(m, SCTP_MBUF_IALLOC);
  409         }
  410 #endif
  411         return (m);
  412 }
  413 
  414 
  415 #ifdef SCTP_PACKET_LOGGING
  416 void
  417 sctp_packet_log(struct mbuf *m)
  418 {
  419         int *lenat, thisone;
  420         void *copyto;
  421         uint32_t *tick_tock;
  422         int length;
  423         int total_len;
  424         int grabbed_lock = 0;
  425         int value, newval, thisend, thisbegin;
  426 
  427         /*
  428          * Buffer layout. -sizeof this entry (total_len) -previous end
  429          * (value) -ticks of log      (ticks) o -ip packet o -as logged -
  430          * where this started (thisbegin) x <--end points here
  431          */
  432         length = SCTP_HEADER_LEN(m);
  433         total_len = SCTP_SIZE32((length + (4 * sizeof(int))));
  434         /* Log a packet to the buffer. */
  435         if (total_len > SCTP_PACKET_LOG_SIZE) {
  436                 /* Can't log this packet I have not a buffer big enough */
  437                 return;
  438         }
  439         if (length < (int)(SCTP_MIN_V4_OVERHEAD + sizeof(struct sctp_cookie_ack_chunk))) {
  440                 return;
  441         }
  442         atomic_add_int(&SCTP_BASE_VAR(packet_log_writers), 1);
  443 try_again:
  444         if (SCTP_BASE_VAR(packet_log_writers) > SCTP_PKTLOG_WRITERS_NEED_LOCK) {
  445                 SCTP_IP_PKTLOG_LOCK();
  446                 grabbed_lock = 1;
  447 again_locked:
  448                 value = SCTP_BASE_VAR(packet_log_end);
  449                 newval = SCTP_BASE_VAR(packet_log_end) + total_len;
  450                 if (newval >= SCTP_PACKET_LOG_SIZE) {
  451                         /* we wrapped */
  452                         thisbegin = 0;
  453                         thisend = total_len;
  454                 } else {
  455                         thisbegin = SCTP_BASE_VAR(packet_log_end);
  456                         thisend = newval;
  457                 }
  458                 if (!(atomic_cmpset_int(&SCTP_BASE_VAR(packet_log_end), value, thisend))) {
  459                         goto again_locked;
  460                 }
  461         } else {
  462                 value = SCTP_BASE_VAR(packet_log_end);
  463                 newval = SCTP_BASE_VAR(packet_log_end) + total_len;
  464                 if (newval >= SCTP_PACKET_LOG_SIZE) {
  465                         /* we wrapped */
  466                         thisbegin = 0;
  467                         thisend = total_len;
  468                 } else {
  469                         thisbegin = SCTP_BASE_VAR(packet_log_end);
  470                         thisend = newval;
  471                 }
  472                 if (!(atomic_cmpset_int(&SCTP_BASE_VAR(packet_log_end), value, thisend))) {
  473                         goto try_again;
  474                 }
  475         }
  476         /* Sanity check */
  477         if (thisend >= SCTP_PACKET_LOG_SIZE) {
  478                 SCTP_PRINTF("Insanity stops a log thisbegin:%d thisend:%d writers:%d lock:%d end:%d\n",
  479                     thisbegin,
  480                     thisend,
  481                     SCTP_BASE_VAR(packet_log_writers),
  482                     grabbed_lock,
  483                     SCTP_BASE_VAR(packet_log_end));
  484                 SCTP_BASE_VAR(packet_log_end) = 0;
  485                 goto no_log;
  486 
  487         }
  488         lenat = (int *)&SCTP_BASE_VAR(packet_log_buffer)[thisbegin];
  489         *lenat = total_len;
  490         lenat++;
  491         *lenat = value;
  492         lenat++;
  493         tick_tock = (uint32_t *) lenat;
  494         lenat++;
  495         *tick_tock = sctp_get_tick_count();
  496         copyto = (void *)lenat;
  497         thisone = thisend - sizeof(int);
  498         lenat = (int *)&SCTP_BASE_VAR(packet_log_buffer)[thisone];
  499         *lenat = thisbegin;
  500         if (grabbed_lock) {
  501                 SCTP_IP_PKTLOG_UNLOCK();
  502                 grabbed_lock = 0;
  503         }
  504         m_copydata(m, 0, length, (caddr_t)copyto);
  505 no_log:
  506         if (grabbed_lock) {
  507                 SCTP_IP_PKTLOG_UNLOCK();
  508         }
  509         atomic_subtract_int(&SCTP_BASE_VAR(packet_log_writers), 1);
  510 }
  511 
  512 
  513 int
  514 sctp_copy_out_packet_log(uint8_t * target, int length)
  515 {
  516         /*
  517          * We wind through the packet log starting at start copying up to
  518          * length bytes out. We return the number of bytes copied.
  519          */
  520         int tocopy, this_copy;
  521         int *lenat;
  522         int did_delay = 0;
  523 
  524         tocopy = length;
  525         if (length < (int)(2 * sizeof(int))) {
  526                 /* not enough room */
  527                 return (0);
  528         }
  529         if (SCTP_PKTLOG_WRITERS_NEED_LOCK) {
  530                 atomic_add_int(&SCTP_BASE_VAR(packet_log_writers), SCTP_PKTLOG_WRITERS_NEED_LOCK);
  531 again:
  532                 if ((did_delay == 0) && (SCTP_BASE_VAR(packet_log_writers) != SCTP_PKTLOG_WRITERS_NEED_LOCK)) {
  533                         /*
  534                          * we delay here for just a moment hoping the
  535                          * writer(s) that were present when we entered will
  536                          * have left and we only have locking ones that will
  537                          * contend with us for the lock. This does not
  538                          * assure 100% access, but its good enough for a
  539                          * logging facility like this.
  540                          */
  541                         did_delay = 1;
  542                         DELAY(10);
  543                         goto again;
  544                 }
  545         }
  546         SCTP_IP_PKTLOG_LOCK();
  547         lenat = (int *)target;
  548         *lenat = SCTP_BASE_VAR(packet_log_end);
  549         lenat++;
  550         this_copy = min((length - sizeof(int)), SCTP_PACKET_LOG_SIZE);
  551         memcpy((void *)lenat, (void *)SCTP_BASE_VAR(packet_log_buffer), this_copy);
  552         if (SCTP_PKTLOG_WRITERS_NEED_LOCK) {
  553                 atomic_subtract_int(&SCTP_BASE_VAR(packet_log_writers),
  554                     SCTP_PKTLOG_WRITERS_NEED_LOCK);
  555         }
  556         SCTP_IP_PKTLOG_UNLOCK();
  557         return (this_copy + sizeof(int));
  558 }
  559 
  560 #endif

Cache object: 9bbb7621a4567317eafe2637acd721a0


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