src/neighbors.cc

   1 /*
   2  * DEBUG: section 15    Neighbor Routines
   3  * AUTHOR: Harvest Derived
   4  *
   5  * SQUID Web Proxy Cache          http://www.squid-cache.org/
   6  * ----------------------------------------------------------
   7  *
   8  *  Squid is the result of efforts by numerous individuals from
   9  *  the Internet community; see the CONTRIBUTORS file for full
  10  *  details.   Many organizations have provided support for Squid's
  11  *  development; see the SPONSORS file for full details.  Squid is
  12  *  Copyrighted (C) 2001 by the Regents of the University of
  13  *  California; see the COPYRIGHT file for full details.  Squid
  14  *  incorporates software developed and/or copyrighted by other
  15  *  sources; see the CREDITS file for full details.
  16  *
  17  *  This program is free software; you can redistribute it and/or modify
  18  *  it under the terms of the GNU General Public License as published by
  19  *  the Free Software Foundation; either version 2 of the License, or
  20  *  (at your option) any later version.
  21  *
  22  *  This program is distributed in the hope that it will be useful,
  23  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  24  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  25  *  GNU General Public License for more details.
  26  *
  27  *  You should have received a copy of the GNU General Public License
  28  *  along with this program; if not, write to the Free Software
  29  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
  30  *
  31  */
  32
  33 #include "squid.h"
  34 #include "ProtoPort.h"
  35 #include "acl/FilledChecklist.h"
  36 #include "comm/Connection.h"
  37 #include "comm/ConnOpener.h"
  38 #include "event.h"
  39 #include "htcp.h"
  40 #include "HttpRequest.h"
  41 #include "ICP.h"
  42 #include "ip/tools.h"
  43 #include "MemObject.h"
  44 #include "PeerDigest.h"
  45 #include "PeerSelectState.h"
  46 #include "SquidMath.h"
  47 #include "SquidTime.h"
  48 #include "Store.h"
  49 #include "icmp/net_db.h"
  50 #include "ip/Address.h"
  51 #include "ip/tools.h"
  52 #include "mgr/Registration.h"
  53
  54 /* count mcast group peers every 15 minutes */
  55 #define MCAST_COUNT_RATE 900
  56
  57 int peerAllowedToUse(const peer *, HttpRequest *);
  58 static int peerWouldBePinged(const peer *, HttpRequest *);
  59 static void neighborRemove(peer *);
  60 static void neighborAlive(peer *, const MemObject *, const icp_common_t *);
  61 #if USE_HTCP
  62 static void neighborAliveHtcp(peer *, const MemObject *, const htcpReplyData *);
  63 #endif
  64 static void neighborCountIgnored(peer *);
  65 static void peerRefreshDNS(void *);
  66 static IPH peerDNSConfigure;
  67 static bool peerProbeConnect(peer *);
  68 static CNCB peerProbeConnectDone;
  69 static void peerCountMcastPeersDone(void *data);
  70 static void peerCountMcastPeersStart(void *data);
  71 static void peerCountMcastPeersSchedule(peer * p, time_t when);
  72 static IRCB peerCountHandleIcpReply;
  73
  74 static void neighborIgnoreNonPeer(const Ip::Address &, icp_opcode);
  75 static OBJH neighborDumpPeers;
  76 static OBJH neighborDumpNonPeers;
  77 static void dump_peers(StoreEntry * sentry, peer * peers);
  78
  79 static icp_common_t echo_hdr;
  80 static u_short echo_port;
  81
  82 static int NLateReplies = 0;
  83 static peer *first_ping = NULL;
  84
  85 const char *
  86 neighborTypeStr(const peer * p)
  87 {
  88     if (p->type == PEER_NONE)
  89         return "Non-Peer";
  90
  91     if (p->type == PEER_SIBLING)
  92         return "Sibling";
  93
  94     if (p->type == PEER_MULTICAST)
  95         return "Multicast Group";
  96
  97     return "Parent";
  98 }
  99
 100
 101 peer *
 102 whichPeer(const Ip::Address &from)
 103 {
 104     int j;
 105
 106     peer *p = NULL;
 107     debugs(15, 3, "whichPeer: from " << from);
 108
 109     for (p = Config.peers; p; p = p->next) {
 110         for (j = 0; j < p->n_addresses; j++) {
 111             if (from == p->addresses[j] && from.GetPort() == p->icp.port) {
 112                 return p;
 113             }
 114         }
 115     }
 116
 117     return NULL;
 118 }
 119
 120 peer_t
 121 neighborType(const peer * p, const HttpRequest * request)
 122 {
 123
 124     const struct _domain_type *d = NULL;
 125
 126     for (d = p->typelist; d; d = d->next) {
 127         if (0 == matchDomainName(request->GetHost(), d->domain))
 128             if (d->type != PEER_NONE)
 129                 return d->type;
 130     }
 131 #if PEER_MULTICAST_SIBLINGS
 132     if (p->type == PEER_MULTICAST)
 133         if (p->options.mcast_siblings)
 134             return PEER_SIBLING;
 135 #endif
 136
 137     return p->type;
 138 }
 139
 140 /*
 141  * peerAllowedToUse
 142  *
 143  * this function figures out if it is appropriate to fetch REQUEST
 144  * from PEER.
 145  */
 146 int
 147 peerAllowedToUse(const peer * p, HttpRequest * request)
 148 {
 149
 150     const struct _domain_ping *d = NULL;
 151     int do_ping = 1;
 152     assert(request != NULL);
 153
 154     if (neighborType(p, request) == PEER_SIBLING) {
 155 #if PEER_MULTICAST_SIBLINGS
 156         if (p->type == PEER_MULTICAST && p->options.mcast_siblings &&
 157                 (request->flags.nocache || request->flags.refresh || request->flags.loopdetect || request->flags.need_validation))
 158             debugs(15, 2, "peerAllowedToUse(" << p->name << ", " << request->GetHost() << ") : multicast-siblings optimization match");
 159 #endif
 160         if (request->flags.nocache)
 161             return 0;
 162
 163         if (request->flags.refresh)
 164             return 0;
 165
 166         if (request->flags.loopdetect)
 167             return 0;
 168
 169         if (request->flags.need_validation)
 170             return 0;
 171     }
 172
 173     if (p->peer_domain == NULL && p->access == NULL)
 174         return do_ping;
 175
 176     do_ping = 0;
 177
 178     for (d = p->peer_domain; d; d = d->next) {
 179         if (0 == matchDomainName(request->GetHost(), d->domain)) {
 180             do_ping = d->do_ping;
 181             break;
 182         }
 183
 184         do_ping = !d->do_ping;
 185     }
 186
 187     if (p->peer_domain && 0 == do_ping)
 188         return do_ping;
 189
 190     if (p->access == NULL)
 191         return do_ping;
 192
 193     ACLFilledChecklist checklist(p->access, request, NULL);
 194     checklist.src_addr = request->client_addr;
 195     checklist.my_addr = request->my_addr;
 196
 197 #if 0 && USE_IDENT
 198     /*
 199      * this is currently broken because 'request->user_ident' has been
 200      * moved to conn->rfc931 and we don't have access to the parent
 201      * ConnStateData here.
 202      */
 203     if (request->user_ident[0])
 204         xstrncpy(checklist.rfc931, request->user_ident, USER_IDENT_SZ);
 205
 206 #endif
 207
 208     return checklist.fastCheck();
 209 }
 210
 211 /* Return TRUE if it is okay to send an ICP request to this peer.   */
 212 static int
 213 peerWouldBePinged(const peer * p, HttpRequest * request)
 214 {
 215     if (!peerAllowedToUse(p, request))
 216         return 0;
 217
 218     if (p->options.no_query)
 219         return 0;
 220
 221     if (p->options.background_ping && (squid_curtime - p->stats.last_query < Config.backgroundPingRate))
 222         return 0;
 223
 224     if (p->options.mcast_responder)
 225         return 0;
 226
 227     if (p->n_addresses == 0)
 228         return 0;
 229
 230     if (p->icp.port == 0)
 231         return 0;
 232
 233     /* the case below seems strange, but can happen if the
 234      * URL host is on the other side of a firewall */
 235     if (p->type == PEER_SIBLING)
 236         if (!request->flags.hierarchical)
 237             return 0;
 238
 239     /* Ping dead peers every timeout interval */
 240     if (squid_curtime - p->stats.last_query > Config.Timeout.deadPeer)
 241         return 1;
 242
 243     if (!neighborUp(p))
 244         return 0;
 245
 246     return 1;
 247 }
 248
 249 /* Return TRUE if it is okay to send an HTTP request to this peer. */
 250 int
 251 peerHTTPOkay(const peer * p, HttpRequest * request)
 252 {
 253     if (!peerAllowedToUse(p, request))
 254         return 0;
 255
 256     if (!neighborUp(p))
 257         return 0;
 258
 259     if (p->max_conn)
 260         if (p->stats.conn_open >= p->max_conn)
 261             return 0;
 262
 263     return 1;
 264 }
 265
 266 int
 267 neighborsCount(HttpRequest * request)
 268 {
 269     peer *p = NULL;
 270     int count = 0;
 271
 272     for (p = Config.peers; p; p = p->next)
 273         if (peerWouldBePinged(p, request))
 274             count++;
 275
 276     debugs(15, 3, "neighborsCount: " << count);
 277
 278     return count;
 279 }
 280
 281 peer *
 282 getFirstUpParent(HttpRequest * request)
 283 {
 284     peer *p = NULL;
 285
 286     for (p = Config.peers; p; p = p->next) {
 287         if (!neighborUp(p))
 288             continue;
 289
 290         if (neighborType(p, request) != PEER_PARENT)
 291             continue;
 292
 293         if (!peerHTTPOkay(p, request))
 294             continue;
 295
 296         break;
 297     }
 298
 299     debugs(15, 3, "getFirstUpParent: returning " << (p ? p->host : "NULL"));
 300     return p;
 301 }
 302
 303 peer *
 304 getRoundRobinParent(HttpRequest * request)
 305 {
 306     peer *p;
 307     peer *q = NULL;
 308
 309     for (p = Config.peers; p; p = p->next) {
 310         if (!p->options.roundrobin)
 311             continue;
 312
 313         if (neighborType(p, request) != PEER_PARENT)
 314             continue;
 315
 316         if (!peerHTTPOkay(p, request))
 317             continue;
 318
 319         if (p->weight == 0)
 320             continue;
 321
 322         if (q) {
 323             if (p->weight == q->weight) {
 324                 if (q->rr_count < p->rr_count)
 325                     continue;
 326             } else if ( ((double) q->rr_count / q->weight) < ((double) p->rr_count / p->weight)) {
 327                 continue;
 328             }
 329         }
 330
 331         q = p;
 332     }
 333
 334     if (q)
 335         q->rr_count++;
 336
 337     debugs(15, 3, HERE << "returning " << (q ? q->host : "NULL"));
 338
 339     return q;
 340 }
 341
 342 peer *
 343 getWeightedRoundRobinParent(HttpRequest * request)
 344 {
 345     peer *p;
 346     peer *q = NULL;
 347     int weighted_rtt;
 348
 349     for (p = Config.peers; p; p = p->next) {
 350         if (!p->options.weighted_roundrobin)
 351             continue;
 352
 353         if (neighborType(p, request) != PEER_PARENT)
 354             continue;
 355
 356         if (!peerHTTPOkay(p, request))
 357             continue;
 358
 359         if (q && q->rr_count < p->rr_count)
 360             continue;
 361
 362         q = p;
 363     }
 364
 365     if (q && q->rr_count > 1000000)
 366         for (p = Config.peers; p; p = p->next) {
 367             if (!p->options.weighted_roundrobin)
 368                 continue;
 369
 370             if (neighborType(p, request) != PEER_PARENT)
 371                 continue;
 372
 373             p->rr_count = 0;
 374         }
 375
 376     if (q) {
 377         weighted_rtt = (q->stats.rtt - q->basetime) / q->weight;
 378
 379         if (weighted_rtt < 1)
 380             weighted_rtt = 1;
 381
 382         q->rr_count += weighted_rtt;
 383
 384         debugs(15, 3, "getWeightedRoundRobinParent: weighted_rtt " << weighted_rtt);
 385     }
 386
 387     debugs(15, 3, "getWeightedRoundRobinParent: returning " << (q ? q->host : "NULL"));
 388     return q;
 389 }
 390
 391 /**
 392  * This gets called every 5 minutes to clear the round-robin counter.
 393  * The exact timing is an arbitrary default, set on estimate timing of a
 394  * large number of requests in a high-performance environment during the
 395  * period. The larger the number of requests between cycled resets the
 396  * more balanced the operations.
 397  *
 398  \param data    unused.
 399  \todo Make the reset timing a selectable parameter in squid.conf
 400  */
 401 static void
 402 peerClearRRLoop(void *data)
 403 {
 404     peerClearRR();
 405     eventAdd("peerClearRR", peerClearRRLoop, data, 5 * 60.0, 0);
 406 }
 407
 408 /**
 409  * This gets called on startup and restart to kick off the peer round-robin
 410  * maintenance event. It ensures that no matter how many times its called
 411  * no more than one event is scheduled.
 412  */
 413 void
 414 peerClearRRStart(void)
 415 {
 416     static int event_added = 0;
 417     if (!event_added) {
 418         peerClearRRLoop(NULL);
 419     }
 420 }
 421
 422 /**
 423  * Called whenever the round-robin counters need to be reset to a sane state.
 424  * So far those times are:
 425  *  - On startup and reconfigure - to set the counters to sane initial settings.
 426  *  -  When a peer has revived from dead, to prevent the revived peer being
 427  *     flooded with requests which it has 'missed' during the down period.
 428  */
 429 void
 430 peerClearRR()
 431 {
 432     peer *p = NULL;
 433     for (p = Config.peers; p; p = p->next) {
 434         p->rr_count = 0;
 435     }
 436 }
 437
 438 /**
 439  * Perform all actions when a peer is detected revived.
 440  */
 441 void
 442 peerAlive(peer *p)
 443 {
 444     if (p->stats.logged_state == PEER_DEAD && p->tcp_up) {
 445         debugs(15, 1, "Detected REVIVED " << neighborTypeStr(p) << ": " << p->name);
 446         p->stats.logged_state = PEER_ALIVE;
 447         peerClearRR();
 448     }
 449
 450     p->stats.last_reply = squid_curtime;
 451     p->stats.probe_start = 0;
 452 }
 453
 454 peer *
 455 getDefaultParent(HttpRequest * request)
 456 {
 457     peer *p = NULL;
 458
 459     for (p = Config.peers; p; p = p->next) {
 460         if (neighborType(p, request) != PEER_PARENT)
 461             continue;
 462
 463         if (!p->options.default_parent)
 464             continue;
 465
 466         if (!peerHTTPOkay(p, request))
 467             continue;
 468
 469         debugs(15, 3, "getDefaultParent: returning " << p->host);
 470
 471         return p;
 472     }
 473
 474     debugs(15, 3, "getDefaultParent: returning NULL");
 475     return NULL;
 476 }
 477
 478 /*
 479  * XXX DW thinks this function is equivalent to/redundant with
 480  * getFirstUpParent().  peerHTTPOkay() only returns true if the
 481  * peer is UP anyway, so this function would not return a
 482  * DOWN parent.
 483  */
 484 peer *
 485 getAnyParent(HttpRequest * request)
 486 {
 487     peer *p = NULL;
 488
 489     for (p = Config.peers; p; p = p->next) {
 490         if (neighborType(p, request) != PEER_PARENT)
 491             continue;
 492
 493         if (!peerHTTPOkay(p, request))
 494             continue;
 495
 496         debugs(15, 3, "getAnyParent: returning " << p->host);
 497
 498         return p;
 499     }
 500
 501     debugs(15, 3, "getAnyParent: returning NULL");
 502     return NULL;
 503 }
 504
 505 peer *
 506 getNextPeer(peer * p)
 507 {
 508     return p->next;
 509 }
 510
 511 peer *
 512 getFirstPeer(void)
 513 {
 514     return Config.peers;
 515 }
 516
 517 static void
 518 neighborRemove(peer * target)
 519 {
 520     peer *p = NULL;
 521     peer **P = NULL;
 522     p = Config.peers;
 523     P = &Config.peers;
 524
 525     while (p) {
 526         if (target == p)
 527             break;
 528
 529         P = &p->next;
 530
 531         p = p->next;
 532     }
 533
 534     if (p) {
 535         *P = p->next;
 536         cbdataFree(p);
 537         Config.npeers--;
 538     }
 539
 540     first_ping = Config.peers;
 541 }
 542
 543 static void
 544 neighborsRegisterWithCacheManager()
 545 {
 546     Mgr::RegisterAction("server_list",
 547                         "Peer Cache Statistics",
 548                         neighborDumpPeers, 0, 1);
 549
 550     if (Comm::IsConnOpen(icpIncomingConn)) {
 551         Mgr::RegisterAction("non_peers",
 552                             "List of Unknown sites sending ICP messages",
 553                             neighborDumpNonPeers, 0, 1);
 554     }
 555 }
 556
 557 void
 558 neighbors_init(void)
 559 {
 560     struct servent *sep = NULL;
 561     const char *me = getMyHostname();
 562     peer *thisPeer = NULL;
 563     peer *next = NULL;
 564
 565     neighborsRegisterWithCacheManager();
 566
 567     if (Comm::IsConnOpen(icpIncomingConn)) {
 568
 569         for (thisPeer = Config.peers; thisPeer; thisPeer = next) {
 570             http_port_list *s = NULL;
 571             next = thisPeer->next;
 572
 573             if (0 != strcmp(thisPeer->host, me))
 574                 continue;
 575
 576             for (s = Config.Sockaddr.http; s; s = s->next) {
 577                 if (thisPeer->http_port != s->s.GetPort())
 578                     continue;
 579
 580                 debugs(15, DBG_IMPORTANT, "WARNING: Peer looks like this host");
 581
 582                 debugs(15, DBG_IMPORTANT, "         Ignoring " <<
 583                        neighborTypeStr(thisPeer) << " " << thisPeer->host <<
 584                        "/" << thisPeer->http_port << "/" <<
 585                        thisPeer->icp.port);
 586
 587                 neighborRemove(thisPeer);
 588             }
 589         }
 590     }
 591
 592     peerRefreshDNS((void *) 1);
 593
 594     if (echo_hdr.opcode == ICP_INVALID) {
 595         echo_hdr.opcode = ICP_SECHO;
 596         echo_hdr.version = ICP_VERSION_CURRENT;
 597         echo_hdr.length = 0;
 598         echo_hdr.reqnum = 0;
 599         echo_hdr.flags = 0;
 600         echo_hdr.pad = 0;
 601         theIcpPublicHostID.GetInAddr( *((struct in_addr*)&echo_hdr.shostid) );
 602         sep = getservbyname("echo", "udp");
 603         echo_port = sep ? ntohs((u_short) sep->s_port) : 7;
 604     }
 605
 606     first_ping = Config.peers;
 607 }
 608
 609 int
 610 neighborsUdpPing(HttpRequest * request,
 611                  StoreEntry * entry,
 612                  IRCB * callback,
 613                  void *callback_data,
 614                  int *exprep,
 615                  int *timeout)
 616 {
 617     const char *url = entry->url();
 618     MemObject *mem = entry->mem_obj;
 619     peer *p = NULL;
 620     int i;
 621     int reqnum = 0;
 622     int flags;
 623     icp_common_t *query;
 624     int queries_sent = 0;
 625     int peers_pinged = 0;
 626     int parent_timeout = 0, parent_exprep = 0;
 627     int sibling_timeout = 0, sibling_exprep = 0;
 628     int mcast_timeout = 0, mcast_exprep = 0;
 629
 630     if (Config.peers == NULL)
 631         return 0;
 632
 633     assert(entry->swap_status == SWAPOUT_NONE);
 634
 635     mem->start_ping = current_time;
 636
 637     mem->ping_reply_callback = callback;
 638
 639     mem->ircb_data = callback_data;
 640
 641     reqnum = icpSetCacheKey((const cache_key *)entry->key);
 642
 643     for (i = 0, p = first_ping; i++ < Config.npeers; p = p->next) {
 644         if (p == NULL)
 645             p = Config.peers;
 646
 647         debugs(15, 5, "neighborsUdpPing: Peer " << p->host);
 648
 649         if (!peerWouldBePinged(p, request))
 650             continue;           /* next peer */
 651
 652         peers_pinged++;
 653
 654         debugs(15, 4, "neighborsUdpPing: pinging peer " << p->host << " for '" << url << "'");
 655
 656         debugs(15, 3, "neighborsUdpPing: key = '" << entry->getMD5Text() << "'");
 657
 658         debugs(15, 3, "neighborsUdpPing: reqnum = " << reqnum);
 659
 660 #if USE_HTCP
 661         if (p->options.htcp && !p->options.htcp_only_clr) {
 662             if (Config.Port.htcp <= 0) {
 663                 debugs(15, DBG_CRITICAL, "HTCP is disabled! Cannot send HTCP request to peer.");
 664                 continue;
 665             }
 666
 667             debugs(15, 3, "neighborsUdpPing: sending HTCP query");
 668             if (htcpQuery(entry, request, p) <= 0) continue; // unable to send.
 669         } else
 670 #endif
 671         {
 672             if (Config.Port.icp <= 0 || !Comm::IsConnOpen(icpOutgoingConn)) {
 673                 debugs(15, DBG_CRITICAL, "ICP is disabled! Cannot send ICP request to peer.");
 674                 continue;
 675             } else {
 676
 677                 if (p->type == PEER_MULTICAST)
 678                     mcastSetTtl(icpOutgoingConn->fd, p->mcast.ttl);
 679
 680                 if (p->icp.port == echo_port) {
 681                     debugs(15, 4, "neighborsUdpPing: Looks like a dumb cache, send DECHO ping");
 682                     echo_hdr.reqnum = reqnum;
 683                     query = _icp_common_t::createMessage(ICP_DECHO, 0, url, reqnum, 0);
 684                     icpUdpSend(icpOutgoingConn->fd, p->in_addr, query, LOG_ICP_QUERY, 0);
 685                 } else {
 686                     flags = 0;
 687
 688                     if (Config.onoff.query_icmp)
 689                         if (p->icp.version == ICP_VERSION_2)
 690                             flags |= ICP_FLAG_SRC_RTT;
 691
 692                     query = _icp_common_t::createMessage(ICP_QUERY, flags, url, reqnum, 0);
 693
 694                     icpUdpSend(icpOutgoingConn->fd, p->in_addr, query, LOG_ICP_QUERY, 0);
 695                 }
 696             }
 697         }
 698
 699         queries_sent++;
 700
 701         p->stats.pings_sent++;
 702
 703         if (p->type == PEER_MULTICAST) {
 704             mcast_exprep += p->mcast.n_replies_expected;
 705             mcast_timeout += (p->stats.rtt * p->mcast.n_replies_expected);
 706         } else if (neighborUp(p)) {
 707             /* its alive, expect a reply from it */
 708
 709             if (neighborType(p, request) == PEER_PARENT) {
 710                 parent_exprep++;
 711                 parent_timeout += p->stats.rtt;
 712             } else {
 713                 sibling_exprep++;
 714                 sibling_timeout += p->stats.rtt;
 715             }
 716         } else {
 717             /* Neighbor is dead; ping it anyway, but don't expect a reply */
 718             /* log it once at the threshold */
 719
 720             if (p->stats.logged_state == PEER_ALIVE) {
 721                 debugs(15, 1, "Detected DEAD " << neighborTypeStr(p) << ": " << p->name);
 722                 p->stats.logged_state = PEER_DEAD;
 723             }
 724         }
 725
 726         p->stats.last_query = squid_curtime;
 727
 728         /*
 729          * keep probe_start == 0 for a multicast peer,
 730          * so neighborUp() never says this peer is dead.
 731          */
 732
 733         if ((p->type != PEER_MULTICAST) && (p->stats.probe_start == 0))
 734             p->stats.probe_start = squid_curtime;
 735     }
 736
 737     if ((first_ping = first_ping->next) == NULL)
 738         first_ping = Config.peers;
 739
 740     /*
 741      * How many replies to expect?
 742      */
 743     *exprep = parent_exprep + sibling_exprep + mcast_exprep;
 744
 745     /*
 746      * If there is a configured timeout, use it
 747      */
 748     if (Config.Timeout.icp_query)
 749         *timeout = Config.Timeout.icp_query;
 750     else {
 751         if (*exprep > 0) {
 752             if (parent_exprep)
 753                 *timeout = 2 * parent_timeout / parent_exprep;
 754             else if (mcast_exprep)
 755                 *timeout = 2 * mcast_timeout / mcast_exprep;
 756             else
 757                 *timeout = 2 * sibling_timeout / sibling_exprep;
 758         } else
 759             *timeout = 2000;    /* 2 seconds */
 760
 761         if (Config.Timeout.icp_query_max)
 762             if (*timeout > Config.Timeout.icp_query_max)
 763                 *timeout = Config.Timeout.icp_query_max;
 764
 765         if (*timeout < Config.Timeout.icp_query_min)
 766             *timeout = Config.Timeout.icp_query_min;
 767     }
 768
 769     return peers_pinged;
 770 }
 771
 772 /* lookup the digest of a given peer */
 773 lookup_t
 774 peerDigestLookup(peer * p, HttpRequest * request)
 775 {
 776 #if USE_CACHE_DIGESTS
 777     const cache_key *key = request ? storeKeyPublicByRequest(request) : NULL;
 778     assert(p);
 779     assert(request);
 780     debugs(15, 5, "peerDigestLookup: peer " << p->host);
 781     /* does the peeer have a valid digest? */
 782
 783     if (!p->digest) {
 784         debugs(15, 5, "peerDigestLookup: gone!");
 785         return LOOKUP_NONE;
 786     } else if (!peerHTTPOkay(p, request)) {
 787         debugs(15, 5, "peerDigestLookup: !peerHTTPOkay");
 788         return LOOKUP_NONE;
 789     } else if (!p->digest->flags.needed) {
 790         debugs(15, 5, "peerDigestLookup: note need");
 791         peerDigestNeeded(p->digest);
 792         return LOOKUP_NONE;
 793     } else if (!p->digest->flags.usable) {
 794         debugs(15, 5, "peerDigestLookup: !ready && " << (p->digest->flags.requested ? "" : "!") << "requested");
 795         return LOOKUP_NONE;
 796     }
 797
 798     debugs(15, 5, "peerDigestLookup: OK to lookup peer " << p->host);
 799     assert(p->digest->cd);
 800     /* does digest predict a hit? */
 801
 802     if (!cacheDigestTest(p->digest->cd, key))
 803         return LOOKUP_MISS;
 804
 805     debugs(15, 5, "peerDigestLookup: peer " << p->host << " says HIT!");
 806
 807     return LOOKUP_HIT;
 808
 809 #endif
 810
 811     return LOOKUP_NONE;
 812 }
 813
 814 /* select best peer based on cache digests */
 815 peer *
 816 neighborsDigestSelect(HttpRequest * request)
 817 {
 818     peer *best_p = NULL;
 819 #if USE_CACHE_DIGESTS
 820
 821     const cache_key *key;
 822     int best_rtt = 0;
 823     int choice_count = 0;
 824     int ichoice_count = 0;
 825     peer *p;
 826     int p_rtt;
 827     int i;
 828
 829     if (!request->flags.hierarchical)
 830         return NULL;
 831
 832     key = storeKeyPublicByRequest(request);
 833
 834     for (i = 0, p = first_ping; i++ < Config.npeers; p = p->next) {
 835         lookup_t lookup;
 836
 837         if (!p)
 838             p = Config.peers;
 839
 840         if (i == 1)
 841             first_ping = p;
 842
 843         lookup = peerDigestLookup(p, request);
 844
 845         if (lookup == LOOKUP_NONE)
 846             continue;
 847
 848         choice_count++;
 849
 850         if (lookup == LOOKUP_MISS)
 851             continue;
 852
 853         p_rtt = netdbHostRtt(p->host);
 854
 855         debugs(15, 5, "neighborsDigestSelect: peer " << p->host << " rtt: " << p_rtt);
 856
 857         /* is this peer better than others in terms of rtt ? */
 858         if (!best_p || (p_rtt && p_rtt < best_rtt)) {
 859             best_p = p;
 860             best_rtt = p_rtt;
 861
 862             if (p_rtt)          /* informative choice (aka educated guess) */
 863                 ichoice_count++;
 864
 865             debugs(15, 4, "neighborsDigestSelect: peer " << p->host << " leads with rtt " << best_rtt);
 866         }
 867     }
 868
 869     debugs(15, 4, "neighborsDigestSelect: choices: " << choice_count << " (" << ichoice_count << ")");
 870     peerNoteDigestLookup(request, best_p,
 871                          best_p ? LOOKUP_HIT : (choice_count ? LOOKUP_MISS : LOOKUP_NONE));
 872     request->hier.n_choices = choice_count;
 873     request->hier.n_ichoices = ichoice_count;
 874 #endif
 875
 876     return best_p;
 877 }
 878
 879 void
 880 peerNoteDigestLookup(HttpRequest * request, peer * p, lookup_t lookup)
 881 {
 882 #if USE_CACHE_DIGESTS
 883     if (p)
 884         strncpy(request->hier.cd_host, p->host, sizeof(request->hier.cd_host));
 885     else
 886         *request->hier.cd_host = '\0';
 887
 888     request->hier.cd_lookup = lookup;
 889     debugs(15, 4, "peerNoteDigestLookup: peer " << (p? p->host : "<none>") << ", lookup: " << lookup_t_str[lookup]  );
 890 #endif
 891 }
 892
 893 static void
 894 neighborAlive(peer * p, const MemObject * mem, const icp_common_t * header)
 895 {
 896     peerAlive(p);
 897     p->stats.pings_acked++;
 898
 899     if ((icp_opcode) header->opcode <= ICP_END)
 900         p->icp.counts[header->opcode]++;
 901
 902     p->icp.version = (int) header->version;
 903 }
 904
 905 static void
 906 neighborUpdateRtt(peer * p, MemObject * mem)
 907 {
 908     int rtt, rtt_av_factor;
 909
 910     if (!mem)
 911         return;
 912
 913     if (!mem->start_ping.tv_sec)
 914         return;
 915
 916     rtt = tvSubMsec(mem->start_ping, current_time);
 917
 918     if (rtt < 1 || rtt > 10000)
 919         return;
 920
 921     rtt_av_factor = RTT_AV_FACTOR;
 922
 923     if (p->options.weighted_roundrobin)
 924         rtt_av_factor = RTT_BACKGROUND_AV_FACTOR;
 925
 926     p->stats.rtt = Math::intAverage(p->stats.rtt, rtt, p->stats.pings_acked, rtt_av_factor);
 927 }
 928
 929 #if USE_HTCP
 930 static void
 931 neighborAliveHtcp(peer * p, const MemObject * mem, const htcpReplyData * htcp)
 932 {
 933     peerAlive(p);
 934     p->stats.pings_acked++;
 935     p->htcp.counts[htcp->hit ? 1 : 0]++;
 936     p->htcp.version = htcp->version;
 937 }
 938
 939 #endif
 940
 941 static void
 942 neighborCountIgnored(peer * p)
 943 {
 944     if (p == NULL)
 945         return;
 946
 947     p->stats.ignored_replies++;
 948
 949     NLateReplies++;
 950 }
 951
 952 static peer *non_peers = NULL;
 953
 954 static void
 955 neighborIgnoreNonPeer(const Ip::Address &from, icp_opcode opcode)
 956 {
 957     peer *np;
 958
 959     for (np = non_peers; np; np = np->next) {
 960         if (np->in_addr != from)
 961             continue;
 962
 963         if (np->in_addr.GetPort() != from.GetPort())
 964             continue;
 965
 966         break;
 967     }
 968
 969     if (np == NULL) {
 970         np = (peer *)xcalloc(1, sizeof(peer));
 971         np->in_addr = from;
 972         np->icp.port = from.GetPort();
 973         np->type = PEER_NONE;
 974         np->host = new char[MAX_IPSTRLEN];
 975         from.NtoA(np->host,MAX_IPSTRLEN);
 976         np->next = non_peers;
 977         non_peers = np;
 978     }
 979
 980     np->icp.counts[opcode]++;
 981
 982     if (isPowTen(++np->stats.ignored_replies))
 983         debugs(15, 1, "WARNING: Ignored " << np->stats.ignored_replies << " replies from non-peer " << np->host);
 984 }
 985
 986 /* ignoreMulticastReply
 987  *
 988  * * We want to ignore replies from multicast peers if the
 989  * * cache_host_domain rules would normally prevent the peer
 990  * * from being used
 991  */
 992 static int
 993 ignoreMulticastReply(peer * p, MemObject * mem)
 994 {
 995     if (p == NULL)
 996         return 0;
 997
 998     if (!p->options.mcast_responder)
 999         return 0;
1000
1001     if (peerHTTPOkay(p, mem->request))
1002         return 0;
1003
1004     return 1;
1005 }
1006
1007 /**
1008  * I should attach these records to the entry.  We take the first
1009  * hit we get our wait until everyone misses.  The timeout handler
1010  * call needs to nip this shopping list or call one of the misses.
1011  *
1012  * If a hit process is already started, then sobeit
1013  */
1014 void
1015 neighborsUdpAck(const cache_key * key, icp_common_t * header, const Ip::Address &from)
1016 {
1017     peer *p = NULL;
1018     StoreEntry *entry;
1019     MemObject *mem = NULL;
1020     peer_t ntype = PEER_NONE;
1021     icp_opcode opcode = (icp_opcode) header->opcode;
1022
1023     debugs(15, 6, "neighborsUdpAck: opcode " << opcode << " '" << storeKeyText(key) << "'");
1024
1025     if (NULL != (entry = Store::Root().get(key)))
1026         mem = entry->mem_obj;
1027
1028     if ((p = whichPeer(from)))
1029         neighborAlive(p, mem, header);
1030
1031     if (opcode > ICP_END)
1032         return;
1033
1034     const char *opcode_d = icp_opcode_str[opcode];
1035
1036     if (p)
1037         neighborUpdateRtt(p, mem);
1038
1039     /* Does the entry exist? */
1040     if (NULL == entry) {
1041         debugs(12, 3, "neighborsUdpAck: Cache key '" << storeKeyText(key) << "' not found");
1042         neighborCountIgnored(p);
1043         return;
1044     }
1045
1046     /* check if someone is already fetching it */
1047     if (EBIT_TEST(entry->flags, ENTRY_DISPATCHED)) {
1048         debugs(15, 3, "neighborsUdpAck: '" << storeKeyText(key) << "' already being fetched.");
1049         neighborCountIgnored(p);
1050         return;
1051     }
1052
1053     if (mem == NULL) {
1054         debugs(15, 2, "Ignoring " << opcode_d << " for missing mem_obj: " << storeKeyText(key));
1055         neighborCountIgnored(p);
1056         return;
1057     }
1058
1059     if (entry->ping_status != PING_WAITING) {
1060         debugs(15, 2, "neighborsUdpAck: Late " << opcode_d << " for " << storeKeyText(key));
1061         neighborCountIgnored(p);
1062         return;
1063     }
1064
1065     if (entry->lock_count == 0) {
1066         debugs(12, 1, "neighborsUdpAck: '" << storeKeyText(key) << "' has no locks");
1067         neighborCountIgnored(p);
1068         return;
1069     }
1070
1071     debugs(15, 3, "neighborsUdpAck: " << opcode_d << " for '" << storeKeyText(key) << "' from " << (p ? p->host : "source") << " ");
1072
1073     if (p) {
1074         ntype = neighborType(p, mem->request);
1075     }
1076
1077     if (ignoreMulticastReply(p, mem)) {
1078         neighborCountIgnored(p);
1079     } else if (opcode == ICP_MISS) {
1080         if (p == NULL) {
1081             neighborIgnoreNonPeer(from, opcode);
1082         } else {
1083             mem->ping_reply_callback(p, ntype, PROTO_ICP, header, mem->ircb_data);
1084         }
1085     } else if (opcode == ICP_HIT) {
1086         if (p == NULL) {
1087             neighborIgnoreNonPeer(from, opcode);
1088         } else {
1089             header->opcode = ICP_HIT;
1090             mem->ping_reply_callback(p, ntype, PROTO_ICP, header, mem->ircb_data);
1091         }
1092     } else if (opcode == ICP_DECHO) {
1093         if (p == NULL) {
1094             neighborIgnoreNonPeer(from, opcode);
1095         } else if (ntype == PEER_SIBLING) {
1096             debug_trap("neighborsUdpAck: Found non-ICP cache as SIBLING\n");
1097             debug_trap("neighborsUdpAck: non-ICP neighbors must be a PARENT\n");
1098         } else {
1099             mem->ping_reply_callback(p, ntype, PROTO_ICP, header, mem->ircb_data);
1100         }
1101     } else if (opcode == ICP_SECHO) {
1102         if (p) {
1103             debugs(15, 1, "Ignoring SECHO from neighbor " << p->host);
1104             neighborCountIgnored(p);
1105         } else {
1106             debugs(15, 1, "Unsolicited SECHO from " << from);
1107         }
1108     } else if (opcode == ICP_DENIED) {
1109         if (p == NULL) {
1110             neighborIgnoreNonPeer(from, opcode);
1111         } else if (p->stats.pings_acked > 100) {
1112             if (100 * p->icp.counts[ICP_DENIED] / p->stats.pings_acked > 95) {
1113                 debugs(15, 0, "95%% of replies from '" << p->host << "' are UDP_DENIED");
1114                 debugs(15, 0, "Disabling '" << p->host << "', please check your configuration.");
1115                 neighborRemove(p);
1116                 p = NULL;
1117             } else {
1118                 neighborCountIgnored(p);
1119             }
1120         }
1121     } else if (opcode == ICP_MISS_NOFETCH) {
1122         mem->ping_reply_callback(p, ntype, PROTO_ICP, header, mem->ircb_data);
1123     } else {
1124         debugs(15, 0, "neighborsUdpAck: Unexpected ICP reply: " << opcode_d);
1125     }
1126 }
1127
1128 peer *
1129 peerFindByName(const char *name)
1130 {
1131     peer *p = NULL;
1132
1133     for (p = Config.peers; p; p = p->next) {
1134         if (!strcasecmp(name, p->name))
1135             break;
1136     }
1137
1138     return p;
1139 }
1140
1141 peer *
1142 peerFindByNameAndPort(const char *name, unsigned short port)
1143 {
1144     peer *p = NULL;
1145
1146     for (p = Config.peers; p; p = p->next) {
1147         if (strcasecmp(name, p->name))
1148             continue;
1149
1150         if (port != p->http_port)
1151             continue;
1152
1153         break;
1154     }
1155
1156     return p;
1157 }
1158
1159 int
1160 neighborUp(const peer * p)
1161 {
1162     if (!p->tcp_up) {
1163         if (!peerProbeConnect((peer *) p)) {
1164             debugs(15, 8, "neighborUp: DOWN (probed): " << p->host << " (" << p->in_addr << ")");
1165             return 0;
1166         }
1167     }
1168
1169     /*
1170      * The peer can not be UP if we don't have any IP addresses
1171      * for it.
1172      */
1173     if (0 == p->n_addresses) {
1174         debugs(15, 8, "neighborUp: DOWN (no-ip): " << p->host << " (" << p->in_addr << ")");
1175         return 0;
1176     }
1177
1178     if (p->options.no_query) {
1179         debugs(15, 8, "neighborUp: UP (no-query): " << p->host << " (" << p->in_addr << ")");
1180         return 1;
1181     }
1182
1183     if (p->stats.probe_start != 0 &&
1184             squid_curtime - p->stats.probe_start > Config.Timeout.deadPeer) {
1185         debugs(15, 8, "neighborUp: DOWN (dead): " << p->host << " (" << p->in_addr << ")");
1186         return 0;
1187     }
1188
1189     debugs(15, 8, "neighborUp: UP: " << p->host << " (" << p->in_addr << ")");
1190     return 1;
1191 }
1192
1193 void
1194 peerDestroy(void *data)
1195 {
1196     peer *p = (peer *)data;
1197
1198     if (p == NULL)
1199         return;
1200
1201     struct _domain_ping *nl = NULL;
1202
1203     for (struct _domain_ping *l = p->peer_domain; l; l = nl) {
1204         nl = l->next;
1205         safe_free(l->domain);
1206         xfree(l);
1207     }
1208
1209     safe_free(p->host);
1210     safe_free(p->name);
1211     safe_free(p->domain);
1212 #if USE_CACHE_DIGESTS
1213
1214     cbdataReferenceDone(p->digest);
1215 #endif
1216 }
1217
1218 void
1219 peerNoteDigestGone(peer * p)
1220 {
1221 #if USE_CACHE_DIGESTS
1222     cbdataReferenceDone(p->digest);
1223 #endif
1224 }
1225
1226 static void
1227 peerDNSConfigure(const ipcache_addrs *ia, const DnsLookupDetails &, void *data)
1228 {
1229     peer *p = (peer *)data;
1230
1231     int j;
1232
1233     if (p->n_addresses == 0) {
1234         debugs(15, 1, "Configuring " << neighborTypeStr(p) << " " << p->host << "/" << p->http_port << "/" << p->icp.port);
1235
1236         if (p->type == PEER_MULTICAST)
1237             debugs(15, 1, "    Multicast TTL = " << p->mcast.ttl);
1238     }
1239
1240     p->n_addresses = 0;
1241
1242     if (ia == NULL) {
1243         debugs(0, 0, "WARNING: DNS lookup for '" << p->host << "' failed!");
1244         return;
1245     }
1246
1247     if ((int) ia->count < 1) {
1248         debugs(0, 0, "WARNING: No IP address found for '" << p->host << "'!");
1249         return;
1250     }
1251
1252     p->tcp_up = p->connect_fail_limit;
1253
1254     for (j = 0; j < (int) ia->count && j < PEER_MAX_ADDRESSES; j++) {
1255         p->addresses[j] = ia->in_addrs[j];
1256         debugs(15, 2, "--> IP address #" << j << ": " << p->addresses[j]);
1257         p->n_addresses++;
1258     }
1259
1260     p->in_addr.SetEmpty();
1261     p->in_addr = p->addresses[0];
1262     p->in_addr.SetPort(p->icp.port);
1263
1264     if (p->type == PEER_MULTICAST)
1265         peerCountMcastPeersSchedule(p, 10);
1266
1267 #if USE_ICMP
1268     if (p->type != PEER_MULTICAST)
1269         if (!p->options.no_netdb_exchange)
1270             eventAddIsh("netdbExchangeStart", netdbExchangeStart, p, 30.0, 1);
1271 #endif
1272
1273 }
1274
1275 static void
1276 peerRefreshDNS(void *data)
1277 {
1278     peer *p = NULL;
1279
1280     if (eventFind(peerRefreshDNS, NULL))
1281         eventDelete(peerRefreshDNS, NULL);
1282
1283     if (!data && 0 == stat5minClientRequests()) {
1284         /* no recent client traffic, wait a bit */
1285         eventAddIsh("peerRefreshDNS", peerRefreshDNS, NULL, 180.0, 1);
1286         return;
1287     }
1288
1289     for (p = Config.peers; p; p = p->next)
1290         ipcache_nbgethostbyname(p->host, peerDNSConfigure, p);
1291
1292     /* Reconfigure the peers every hour */
1293     eventAddIsh("peerRefreshDNS", peerRefreshDNS, NULL, 3600.0, 1);
1294 }
1295
1296 static void
1297 peerConnectFailedSilent(peer * p)
1298 {
1299     p->stats.last_connect_failure = squid_curtime;
1300
1301     if (!p->tcp_up) {
1302         debugs(15, 2, "TCP connection to " << p->host << "/" << p->http_port <<
1303                " dead");
1304         return;
1305     }
1306
1307     p->tcp_up--;
1308
1309     if (!p->tcp_up) {
1310         debugs(15, 1, "Detected DEAD " << neighborTypeStr(p) << ": " << p->name);
1311         p->stats.logged_state = PEER_DEAD;
1312     }
1313 }
1314
1315 void
1316 peerConnectFailed(peer *p)
1317 {
1318     debugs(15, 1, "TCP connection to " << p->host << "/" << p->http_port << " failed");
1319     peerConnectFailedSilent(p);
1320 }
1321
1322 void
1323 peerConnectSucceded(peer * p)
1324 {
1325     if (!p->tcp_up) {
1326         debugs(15, 2, "TCP connection to " << p->host << "/" << p->http_port << " succeded");
1327         p->tcp_up = p->connect_fail_limit; // NP: so peerAlive(p) works properly.
1328         peerAlive(p);
1329         if (!p->n_addresses)
1330             ipcache_nbgethostbyname(p->host, peerDNSConfigure, p);
1331     } else
1332         p->tcp_up = p->connect_fail_limit;
1333 }
1334
1335 /*
1336 * peerProbeConnect will be called on dead peers by neighborUp
1337 */
1338 static bool
1339 peerProbeConnect(peer * p)
1340 {
1341     time_t ctimeout = p->connect_timeout > 0 ? p->connect_timeout : Config.Timeout.peer_connect;
1342     bool ret = (squid_curtime - p->stats.last_connect_failure) > (ctimeout * 10);
1343
1344     if (p->testing_now > 0)
1345         return ret;/* probe already running */
1346
1347     if (squid_curtime - p->stats.last_connect_probe == 0)
1348         return ret;/* don't probe to often */
1349
1350     /* for each IP address of this peer. find one that we can connect to and probe it. */
1351     for (int i = 0; i < p->n_addresses; i++) {
1352         Comm::ConnectionPointer conn = new Comm::Connection;
1353         conn->remote = p->addresses[i];
1354         conn->remote.SetPort(p->http_port);
1355         getOutgoingAddress(NULL, conn);
1356
1357         p->testing_now++;
1358
1359         AsyncCall::Pointer call = commCbCall(15,3, "peerProbeConnectDone", CommConnectCbPtrFun(peerProbeConnectDone, p));
1360         Comm::ConnOpener *cs = new Comm::ConnOpener(conn, call, ctimeout);
1361         cs->setHost(p->host);
1362         AsyncJob::Start(cs);
1363     }
1364
1365     p->stats.last_connect_probe = squid_curtime;
1366
1367     return ret;
1368 }
1369
1370 static void
1371 peerProbeConnectDone(const Comm::ConnectionPointer &conn, comm_err_t status, int xerrno, void *data)
1372 {
1373     peer *p = (peer*)data;
1374
1375     if (status == COMM_OK) {
1376         peerConnectSucceded(p);
1377     } else {
1378         peerConnectFailedSilent(p);
1379     }
1380
1381     p->testing_now--;
1382     return;
1383 }
1384
1385 static void
1386 peerCountMcastPeersSchedule(peer * p, time_t when)
1387 {
1388     if (p->mcast.flags.count_event_pending)
1389         return;
1390
1391     eventAdd("peerCountMcastPeersStart",
1392              peerCountMcastPeersStart,
1393              p,
1394              (double) when, 1);
1395
1396     p->mcast.flags.count_event_pending = 1;
1397 }
1398
1399 static void
1400 peerCountMcastPeersStart(void *data)
1401 {
1402     peer *p = (peer *)data;
1403     ps_state *psstate;
1404     StoreEntry *fake;
1405     MemObject *mem;
1406     icp_common_t *query;
1407     int reqnum;
1408     LOCAL_ARRAY(char, url, MAX_URL);
1409     assert(p->type == PEER_MULTICAST);
1410     p->mcast.flags.count_event_pending = 0;
1411     snprintf(url, MAX_URL, "http://");
1412     p->in_addr.ToURL(url+7, MAX_URL -8 );
1413     strcat(url, "/");
1414     fake = storeCreateEntry(url, url, request_flags(), METHOD_GET);
1415     HttpRequest *req = HttpRequest::CreateFromUrl(url);
1416     psstate = new ps_state;
1417     psstate->request = HTTPMSGLOCK(req);
1418     psstate->entry = fake;
1419     psstate->callback = NULL;
1420     psstate->callback_data = cbdataReference(p);
1421     psstate->ping.start = current_time;
1422     mem = fake->mem_obj;
1423     mem->request = HTTPMSGLOCK(psstate->request);
1424     mem->start_ping = current_time;
1425     mem->ping_reply_callback = peerCountHandleIcpReply;
1426     mem->ircb_data = psstate;
1427     mcastSetTtl(icpOutgoingConn->fd, p->mcast.ttl);
1428     p->mcast.id = mem->id;
1429     reqnum = icpSetCacheKey((const cache_key *)fake->key);
1430     query = _icp_common_t::createMessage(ICP_QUERY, 0, url, reqnum, 0);
1431     icpUdpSend(icpOutgoingConn->fd, p->in_addr, query, LOG_ICP_QUERY, 0);
1432     fake->ping_status = PING_WAITING;
1433     eventAdd("peerCountMcastPeersDone",
1434              peerCountMcastPeersDone,
1435              psstate,
1436              Config.Timeout.mcast_icp_query / 1000.0, 1);
1437     p->mcast.flags.counting = 1;
1438     peerCountMcastPeersSchedule(p, MCAST_COUNT_RATE);
1439 }
1440
1441 static void
1442 peerCountMcastPeersDone(void *data)
1443 {
1444     ps_state *psstate = (ps_state *)data;
1445     StoreEntry *fake = psstate->entry;
1446
1447     if (cbdataReferenceValid(psstate->callback_data)) {
1448         peer *p = (peer *)psstate->callback_data;
1449         p->mcast.flags.counting = 0;
1450         p->mcast.avg_n_members = Math::doubleAverage(p->mcast.avg_n_members, (double) psstate->ping.n_recv, ++p->mcast.n_times_counted, 10);
1451         debugs(15, 1, "Group " << p->host  << ": " << psstate->ping.n_recv  <<
1452                " replies, "<< std::setw(4)<< std::setprecision(2) <<
1453                p->mcast.avg_n_members <<" average, RTT " << p->stats.rtt);
1454         p->mcast.n_replies_expected = (int) p->mcast.avg_n_members;
1455     }
1456
1457     cbdataReferenceDone(psstate->callback_data);
1458
1459     EBIT_SET(fake->flags, ENTRY_ABORTED);
1460     HTTPMSGUNLOCK(fake->mem_obj->request);
1461     fake->releaseRequest();
1462     fake->unlock();
1463     HTTPMSGUNLOCK(psstate->request);
1464     cbdataFree(psstate);
1465 }
1466
1467 static void
1468 peerCountHandleIcpReply(peer * p, peer_t type, protocol_t proto, void *hdrnotused, void *data)
1469 {
1470     int rtt_av_factor;
1471
1472     ps_state *psstate = (ps_state *)data;
1473     StoreEntry *fake = psstate->entry;
1474     MemObject *mem = fake->mem_obj;
1475     int rtt = tvSubMsec(mem->start_ping, current_time);
1476     assert(proto == PROTO_ICP);
1477     assert(fake);
1478     assert(mem);
1479     psstate->ping.n_recv++;
1480     rtt_av_factor = RTT_AV_FACTOR;
1481
1482     if (p->options.weighted_roundrobin)
1483         rtt_av_factor = RTT_BACKGROUND_AV_FACTOR;
1484
1485     p->stats.rtt = Math::intAverage(p->stats.rtt, rtt, psstate->ping.n_recv, rtt_av_factor);
1486 }
1487
1488 static void
1489 neighborDumpPeers(StoreEntry * sentry)
1490 {
1491     dump_peers(sentry, Config.peers);
1492 }
1493
1494 static void
1495 neighborDumpNonPeers(StoreEntry * sentry)
1496 {
1497     dump_peers(sentry, non_peers);
1498 }
1499
1500 void
1501 dump_peer_options(StoreEntry * sentry, peer * p)
1502 {
1503     if (p->options.proxy_only)
1504         storeAppendPrintf(sentry, " proxy-only");
1505
1506     if (p->options.no_query)
1507         storeAppendPrintf(sentry, " no-query");
1508
1509     if (p->options.background_ping)
1510         storeAppendPrintf(sentry, " background-ping");
1511
1512     if (p->options.no_digest)
1513         storeAppendPrintf(sentry, " no-digest");
1514
1515     if (p->options.default_parent)
1516         storeAppendPrintf(sentry, " default");
1517
1518     if (p->options.roundrobin)
1519         storeAppendPrintf(sentry, " round-robin");
1520
1521     if (p->options.carp)
1522         storeAppendPrintf(sentry, " carp");
1523
1524     if (p->options.userhash)
1525         storeAppendPrintf(sentry, " userhash");
1526
1527     if (p->options.userhash)
1528         storeAppendPrintf(sentry, " sourcehash");
1529
1530     if (p->options.weighted_roundrobin)
1531         storeAppendPrintf(sentry, " weighted-round-robin");
1532
1533     if (p->options.mcast_responder)
1534         storeAppendPrintf(sentry, " multicast-responder");
1535
1536 #if PEER_MULTICAST_SIBLINGS
1537     if (p->options.mcast_siblings)
1538         storeAppendPrintf(sentry, " multicast-siblings");
1539 #endif
1540
1541     if (p->weight != 1)
1542         storeAppendPrintf(sentry, " weight=%d", p->weight);
1543
1544     if (p->options.closest_only)
1545         storeAppendPrintf(sentry, " closest-only");
1546
1547 #if USE_HTCP
1548     if (p->options.htcp) {
1549         storeAppendPrintf(sentry, " htcp");
1550         if (p->options.htcp_oldsquid || p->options.htcp_no_clr || p->options.htcp_no_purge_clr || p->options.htcp_only_clr) {
1551             int doneopts=0;
1552             if (p->options.htcp_oldsquid)
1553                 storeAppendPrintf(sentry, "%soldsquid",(doneopts++>0?",":"="));
1554             if (p->options.htcp_no_clr)
1555                 storeAppendPrintf(sentry, "%sno-clr",(doneopts++>0?",":"="));
1556             if (p->options.htcp_no_purge_clr)
1557                 storeAppendPrintf(sentry, "%sno-purge-clr",(doneopts++>0?",":"="));
1558             if (p->options.htcp_only_clr)
1559                 storeAppendPrintf(sentry, "%sonly-clr",(doneopts++>0?",":"="));
1560         }
1561     }
1562 #endif
1563
1564     if (p->options.no_netdb_exchange)
1565         storeAppendPrintf(sentry, " no-netdb-exchange");
1566
1567 #if DELAY_POOLS
1568
1569     if (p->options.no_delay)
1570         storeAppendPrintf(sentry, " no-delay");
1571
1572 #endif
1573
1574     if (p->login)
1575         storeAppendPrintf(sentry, " login=%s", p->login);
1576
1577     if (p->mcast.ttl > 0)
1578         storeAppendPrintf(sentry, " ttl=%d", p->mcast.ttl);
1579
1580     if (p->connect_timeout > 0)
1581         storeAppendPrintf(sentry, " connect-timeout=%d", (int) p->connect_timeout);
1582
1583     if (p->connect_fail_limit != PEER_TCP_MAGIC_COUNT)
1584         storeAppendPrintf(sentry, " connect-fail-limit=%d", p->connect_fail_limit);
1585
1586 #if USE_CACHE_DIGESTS
1587
1588     if (p->digest_url)
1589         storeAppendPrintf(sentry, " digest-url=%s", p->digest_url);
1590
1591 #endif
1592
1593     if (p->options.allow_miss)
1594         storeAppendPrintf(sentry, " allow-miss");
1595
1596     if (p->options.no_tproxy)
1597         storeAppendPrintf(sentry, " no-tproxy");
1598
1599     if (p->max_conn > 0)
1600         storeAppendPrintf(sentry, " max-conn=%d", p->max_conn);
1601
1602     if (p->options.originserver)
1603         storeAppendPrintf(sentry, " originserver");
1604
1605     if (p->domain)
1606         storeAppendPrintf(sentry, " forceddomain=%s", p->domain);
1607
1608     if (p->connection_auth == 0)
1609         storeAppendPrintf(sentry, " connection-auth=off");
1610     else if (p->connection_auth == 1)
1611         storeAppendPrintf(sentry, " connection-auth=on");
1612     else if (p->connection_auth == 2)
1613         storeAppendPrintf(sentry, " connection-auth=auto");
1614
1615     storeAppendPrintf(sentry, "\n");
1616 }
1617
1618 static void
1619 dump_peers(StoreEntry * sentry, peer * peers)
1620 {
1621     peer *e = NULL;
1622     char ntoabuf[MAX_IPSTRLEN];
1623     struct _domain_ping *d = NULL;
1624     icp_opcode op;
1625     int i;
1626
1627     if (peers == NULL)
1628         storeAppendPrintf(sentry, "There are no neighbors installed.\n");
1629
1630     for (e = peers; e; e = e->next) {
1631         assert(e->host != NULL);
1632         storeAppendPrintf(sentry, "\n%-11.11s: %s\n",
1633                           neighborTypeStr(e),
1634                           e->name);
1635         storeAppendPrintf(sentry, "Host       : %s/%d/%d\n",
1636                           e->host,
1637                           e->http_port,
1638                           e->icp.port);
1639         storeAppendPrintf(sentry, "Flags      :");
1640         dump_peer_options(sentry, e);
1641
1642         for (i = 0; i < e->n_addresses; i++) {
1643             storeAppendPrintf(sentry, "Address[%d] : %s\n", i,
1644                               e->addresses[i].NtoA(ntoabuf,MAX_IPSTRLEN) );
1645         }
1646
1647         storeAppendPrintf(sentry, "Status     : %s\n",
1648                           neighborUp(e) ? "Up" : "Down");
1649         storeAppendPrintf(sentry, "FETCHES    : %d\n", e->stats.fetches);
1650         storeAppendPrintf(sentry, "OPEN CONNS : %d\n", e->stats.conn_open);
1651         storeAppendPrintf(sentry, "AVG RTT    : %d msec\n", e->stats.rtt);
1652
1653         if (!e->options.no_query) {
1654             storeAppendPrintf(sentry, "LAST QUERY : %8d seconds ago\n",
1655                               (int) (squid_curtime - e->stats.last_query));
1656
1657             if (e->stats.last_reply > 0)
1658                 storeAppendPrintf(sentry, "LAST REPLY : %8d seconds ago\n",
1659                                   (int) (squid_curtime - e->stats.last_reply));
1660             else
1661                 storeAppendPrintf(sentry, "LAST REPLY : none received\n");
1662
1663             storeAppendPrintf(sentry, "PINGS SENT : %8d\n", e->stats.pings_sent);
1664
1665             storeAppendPrintf(sentry, "PINGS ACKED: %8d %3d%%\n",
1666                               e->stats.pings_acked,
1667                               Math::intPercent(e->stats.pings_acked, e->stats.pings_sent));
1668         }
1669
1670         storeAppendPrintf(sentry, "IGNORED    : %8d %3d%%\n", e->stats.ignored_replies, Math::intPercent(e->stats.ignored_replies, e->stats.pings_acked));
1671
1672         if (!e->options.no_query) {
1673             storeAppendPrintf(sentry, "Histogram of PINGS ACKED:\n");
1674 #if USE_HTCP
1675
1676             if (e->options.htcp) {
1677                 storeAppendPrintf(sentry, "\tMisses\t%8d %3d%%\n",
1678                                   e->htcp.counts[0],
1679                                   Math::intPercent(e->htcp.counts[0], e->stats.pings_acked));
1680                 storeAppendPrintf(sentry, "\tHits\t%8d %3d%%\n",
1681                                   e->htcp.counts[1],
1682                                   Math::intPercent(e->htcp.counts[1], e->stats.pings_acked));
1683             } else {
1684 #endif
1685
1686                 for (op = ICP_INVALID; op < ICP_END; ++op) {
1687                     if (e->icp.counts[op] == 0)
1688                         continue;
1689
1690                     storeAppendPrintf(sentry, "    %12.12s : %8d %3d%%\n",
1691                                       icp_opcode_str[op],
1692                                       e->icp.counts[op],
1693                                       Math::intPercent(e->icp.counts[op], e->stats.pings_acked));
1694                 }
1695
1696 #if USE_HTCP
1697
1698             }
1699
1700 #endif
1701
1702         }
1703
1704         if (e->stats.last_connect_failure) {
1705             storeAppendPrintf(sentry, "Last failed connect() at: %s\n",
1706                               mkhttpdlogtime(&(e->stats.last_connect_failure)));
1707         }
1708
1709         if (e->peer_domain != NULL) {
1710             storeAppendPrintf(sentry, "DOMAIN LIST: ");
1711
1712             for (d = e->peer_domain; d; d = d->next) {
1713                 storeAppendPrintf(sentry, "%s%s ",
1714                                   d->do_ping ? null_string : "!", d->domain);
1715             }
1716
1717             storeAppendPrintf(sentry, "\n");
1718         }
1719
1720         storeAppendPrintf(sentry, "keep-alive ratio: %d%%\n", Math::intPercent(e->stats.n_keepalives_recv, e->stats.n_keepalives_sent));
1721     }
1722 }
1723
1724 #if USE_HTCP
1725 void
1726 neighborsHtcpReply(const cache_key * key, htcpReplyData * htcp, const Ip::Address &from)
1727 {
1728     StoreEntry *e = Store::Root().get(key);
1729     MemObject *mem = NULL;
1730     peer *p;
1731     peer_t ntype = PEER_NONE;
1732     debugs(15, 6, "neighborsHtcpReply: " <<
1733            (htcp->hit ? "HIT" : "MISS") << " " <<
1734            storeKeyText(key)  );
1735
1736     if (NULL != e)
1737         mem = e->mem_obj;
1738
1739     if ((p = whichPeer(from)))
1740         neighborAliveHtcp(p, mem, htcp);
1741
1742     /* Does the entry exist? */
1743     if (NULL == e) {
1744         debugs(12, 3, "neighyborsHtcpReply: Cache key '" << storeKeyText(key) << "' not found");
1745         neighborCountIgnored(p);
1746         return;
1747     }
1748
1749     /* check if someone is already fetching it */
1750     if (EBIT_TEST(e->flags, ENTRY_DISPATCHED)) {
1751         debugs(15, 3, "neighborsUdpAck: '" << storeKeyText(key) << "' already being fetched.");
1752         neighborCountIgnored(p);
1753         return;
1754     }
1755
1756     if (mem == NULL) {
1757         debugs(15, 2, "Ignoring reply for missing mem_obj: " << storeKeyText(key));
1758         neighborCountIgnored(p);
1759         return;
1760     }
1761
1762     if (e->ping_status != PING_WAITING) {
1763         debugs(15, 2, "neighborsUdpAck: Entry " << storeKeyText(key) << " is not PING_WAITING");
1764         neighborCountIgnored(p);
1765         return;
1766     }
1767
1768     if (e->lock_count == 0) {
1769         debugs(12, 1, "neighborsUdpAck: '" << storeKeyText(key) << "' has no locks");
1770         neighborCountIgnored(p);
1771         return;
1772     }
1773
1774     if (p) {
1775         ntype = neighborType(p, mem->request);
1776         neighborUpdateRtt(p, mem);
1777     }
1778
1779     if (ignoreMulticastReply(p, mem)) {
1780         neighborCountIgnored(p);
1781         return;
1782     }
1783
1784     debugs(15, 3, "neighborsHtcpReply: e = " << e);
1785     mem->ping_reply_callback(p, ntype, PROTO_HTCP, htcp, mem->ircb_data);
1786 }
1787
1788 /*
1789  * Send HTCP CLR messages to all peers configured to receive them.
1790  */
1791 void
1792 neighborsHtcpClear(StoreEntry * e, const char *uri, HttpRequest * req, const HttpRequestMethod &method, htcp_clr_reason reason)
1793 {
1794     peer *p;
1795     char buf[128];
1796
1797     for (p = Config.peers; p; p = p->next) {
1798         if (!p->options.htcp) {
1799             continue;
1800         }
1801         if (p->options.htcp_no_clr) {
1802             continue;
1803         }
1804         if (p->options.htcp_no_purge_clr && reason == HTCP_CLR_PURGE) {
1805             continue;
1806         }
1807         debugs(15, 3, "neighborsHtcpClear: sending CLR to " << p->in_addr.ToURL(buf, 128));
1808         htcpClear(e, uri, req, method, p, reason);
1809     }
1810 }
1811
1812 #endif