src/acl/Asn.cc

   1 /*
   2  * Copyright (C) 1996-2017 The Squid Software Foundation and contributors
   3  *
   4  * Squid software is distributed under GPLv2+ license and includes
   5  * contributions from numerous individuals and organizations.
   6  * Please see the COPYING and CONTRIBUTORS files for details.
   7  */
   8
   9 /* DEBUG: section 53    AS Number handling */
  10
  11 #include "squid.h"
  12 #include "acl/Acl.h"
  13 #include "acl/Asn.h"
  14 #include "acl/Checklist.h"
  15 #include "acl/DestinationAsn.h"
  16 #include "acl/DestinationIp.h"
  17 #include "acl/SourceAsn.h"
  18 #include "acl/Strategised.h"
  19 #include "FwdState.h"
  20 #include "HttpReply.h"
  21 #include "HttpRequest.h"
  22 #include "ipcache.h"
  23 #include "MasterXaction.h"
  24 #include "mgr/Registration.h"
  25 #include "radix.h"
  26 #include "RequestFlags.h"
  27 #include "SquidConfig.h"
  28 #include "Store.h"
  29 #include "StoreClient.h"
  30
  31 #define WHOIS_PORT 43
  32 #define AS_REQBUF_SZ    4096
  33
  34 /* BEGIN of definitions for radix tree entries */
  35
  36 /* 32/128 bits address in memory with length */
  37 class m_ADDR
  38 {
  39 public:
  40     uint8_t len;
  41     Ip::Address addr;
  42
  43     m_ADDR() : len(sizeof(Ip::Address)) {};
  44 };
  45
  46 /* END of definitions for radix tree entries */
  47
  48 /* Head for ip to asn radix tree */
  49
  50 struct squid_radix_node_head *AS_tree_head;
  51
  52 /* explicit instantiation required for some systems */
  53
  54 /// \cond AUTODOCS_IGNORE
  55 template cbdata_type CbDataList<int>::CBDATA_CbDataList;
  56 /// \endcond
  57
  58 /**
  59  * Structure for as number information. it could be simply
  60  * a list but it's coded as a structure for future
  61  * enhancements (e.g. expires)
  62  */
  63 struct as_info {
  64     CbDataList<int> *as_number;
  65     time_t expires;     /* NOTUSED */
  66 };
  67
  68 class ASState
  69 {
  70     CBDATA_CLASS(ASState);
  71
  72 public:
  73     ASState();
  74     ~ASState();
  75
  76     StoreEntry *entry;
  77     store_client *sc;
  78     HttpRequest::Pointer request;
  79     int as_number;
  80     int64_t offset;
  81     int reqofs;
  82     char reqbuf[AS_REQBUF_SZ];
  83     bool dataRead;
  84 };
  85
  86 CBDATA_CLASS_INIT(ASState);
  87
  88 ASState::ASState() :
  89     entry(NULL),
  90     sc(NULL),
  91     request(NULL),
  92     as_number(0),
  93     offset(0),
  94     reqofs(0),
  95     dataRead(false)
  96 {
  97     memset(reqbuf, 0, AS_REQBUF_SZ);
  98 }
  99
 100 ASState::~ASState()
 101 {
 102     debugs(53, 3, entry->url());
 103     storeUnregister(sc, entry, this);
 104     entry->unlock("~ASState");
 105 }
 106
 107 /** entry into the radix tree */
 108 struct rtentry_t {
 109     struct squid_radix_node e_nodes[2];
 110     as_info *e_info;
 111     m_ADDR e_addr;
 112     m_ADDR e_mask;
 113 };
 114
 115 static int asnAddNet(char *, int);
 116
 117 static void asnCacheStart(int as);
 118
 119 static STCB asHandleReply;
 120
 121 #if defined(__cplusplus)
 122 extern "C" {
 123 #endif
 124
 125 static int destroyRadixNode(struct squid_radix_node *rn, void *w);
 126 static int printRadixNode(struct squid_radix_node *rn, void *sentry);
 127
 128 #if defined(__cplusplus)
 129 }
 130 #endif
 131
 132 void asnAclInitialize(ACL * acls);
 133
 134 static void destroyRadixNodeInfo(as_info *);
 135
 136 static OBJH asnStats;
 137
 138 /* PUBLIC */
 139
 140 int
 141 asnMatchIp(CbDataList<int> *data, Ip::Address &addr)
 142 {
 143     struct squid_radix_node *rn;
 144     as_info *e;
 145     m_ADDR m_addr;
 146     CbDataList<int> *a = NULL;
 147     CbDataList<int> *b = NULL;
 148
 149     debugs(53, 3, "asnMatchIp: Called for " << addr );
 150
 151     if (AS_tree_head == NULL)
 152         return 0;
 153
 154     if (addr.isNoAddr())
 155         return 0;
 156
 157     if (addr.isAnyAddr())
 158         return 0;
 159
 160     m_addr.addr = addr;
 161
 162     rn = squid_rn_match(&m_addr, AS_tree_head);
 163
 164     if (rn == NULL) {
 165         debugs(53, 3, "asnMatchIp: Address not in as db.");
 166         return 0;
 167     }
 168
 169     debugs(53, 3, "asnMatchIp: Found in db!");
 170     e = ((rtentry_t *) rn)->e_info;
 171     assert(e);
 172
 173     for (a = data; a; a = a->next)
 174         for (b = e->as_number; b; b = b->next)
 175             if (a->element == b->element) {
 176                 debugs(53, 5, "asnMatchIp: Found a match!");
 177                 return 1;
 178             }
 179
 180     debugs(53, 5, "asnMatchIp: AS not in as db.");
 181     return 0;
 182 }
 183
 184 void
 185 ACLASN::prepareForUse()
 186 {
 187     for (CbDataList<int> *i = data; i; i = i->
 188                                            next)
 189         asnCacheStart(i->element);
 190 }
 191
 192 static void
 193 asnRegisterWithCacheManager(void)
 194 {
 195     Mgr::RegisterAction("asndb", "AS Number Database", asnStats, 0, 1);
 196 }
 197
 198 /* initialize the radix tree structure */
 199
 200 SQUIDCEXTERN int squid_max_keylen;  /* yuck.. this is in lib/radix.c */
 201
 202 void
 203 asnInit(void)
 204 {
 205     static bool inited = false;
 206     squid_max_keylen = 40;
 207
 208     if (!inited) {
 209         inited = true;
 210         squid_rn_init();
 211     }
 212
 213     squid_rn_inithead(&AS_tree_head, 8);
 214
 215     asnRegisterWithCacheManager();
 216 }
 217
 218 void
 219 asnFreeMemory(void)
 220 {
 221     squid_rn_walktree(AS_tree_head, destroyRadixNode, AS_tree_head);
 222
 223     destroyRadixNode((struct squid_radix_node *) 0, (void *) AS_tree_head);
 224 }
 225
 226 static void
 227 asnStats(StoreEntry * sentry)
 228 {
 229     storeAppendPrintf(sentry, "Address    \tAS Numbers\n");
 230     squid_rn_walktree(AS_tree_head, printRadixNode, sentry);
 231 }
 232
 233 /* PRIVATE */
 234
 235 static void
 236 asnCacheStart(int as)
 237 {
 238     LOCAL_ARRAY(char, asres, 4096);
 239     StoreEntry *e;
 240     ASState *asState = new ASState;
 241     debugs(53, 3, "AS " << as);
 242     snprintf(asres, 4096, "whois://%s/!gAS%d", Config.as_whois_server, as);
 243     asState->as_number = as;
 244     const MasterXaction::Pointer mx = new MasterXaction(XactionInitiator::initAsn);
 245     asState->request = HttpRequest::FromUrl(asres, mx);
 246     assert(asState->request != NULL);
 247
 248     if ((e = storeGetPublic(asres, Http::METHOD_GET)) == NULL) {
 249         e = storeCreateEntry(asres, asres, RequestFlags(), Http::METHOD_GET);
 250         asState->sc = storeClientListAdd(e, asState);
 251         FwdState::fwdStart(Comm::ConnectionPointer(), e, asState->request.getRaw());
 252     } else {
 253         e->lock("Asn");
 254         asState->sc = storeClientListAdd(e, asState);
 255     }
 256
 257     asState->entry = e;
 258     StoreIOBuffer readBuffer (AS_REQBUF_SZ, asState->offset, asState->reqbuf);
 259     storeClientCopy(asState->sc, e, readBuffer, asHandleReply, asState);
 260 }
 261
 262 static void
 263 asHandleReply(void *data, StoreIOBuffer result)
 264 {
 265     ASState *asState = (ASState *)data;
 266     StoreEntry *e = asState->entry;
 267     char *s;
 268     char *t;
 269     char *buf = asState->reqbuf;
 270     int leftoversz = -1;
 271
 272     debugs(53, 3, "asHandleReply: Called with size=" << (unsigned int)result.length);
 273     debugs(53, 3, "asHandleReply: buffer='" << buf << "'");
 274
 275     /* First figure out whether we should abort the request */
 276
 277     if (EBIT_TEST(e->flags, ENTRY_ABORTED)) {
 278         delete asState;
 279         return;
 280     }
 281
 282     if (result.length == 0 && asState->dataRead) {
 283         debugs(53, 3, "asHandleReply: Done: " << e->url());
 284         delete asState;
 285         return;
 286     } else if (result.flags.error) {
 287         debugs(53, DBG_IMPORTANT, "asHandleReply: Called with Error set and size=" << (unsigned int) result.length);
 288         delete asState;
 289         return;
 290     } else if (e->getReply()->sline.status() != Http::scOkay) {
 291         debugs(53, DBG_IMPORTANT, "WARNING: AS " << asState->as_number << " whois request failed");
 292         delete asState;
 293         return;
 294     }
 295
 296     /*
 297      * Next, attempt to parse our request
 298      * Remembering that the actual buffer size is retsize + reqofs!
 299      */
 300     s = buf;
 301
 302     while ((size_t)(s - buf) < result.length + asState->reqofs && *s != '\0') {
 303         while (*s && xisspace(*s))
 304             ++s;
 305
 306         for (t = s; *t; ++t) {
 307             if (xisspace(*t))
 308                 break;
 309         }
 310
 311         if (*t == '\0') {
 312             /* oof, word should continue on next block */
 313             break;
 314         }
 315
 316         *t = '\0';
 317         debugs(53, 3, "asHandleReply: AS# " << s << " (" << asState->as_number << ")");
 318         asnAddNet(s, asState->as_number);
 319         s = t + 1;
 320         asState->dataRead = true;
 321     }
 322
 323     /*
 324      * Next, grab the end of the 'valid data' in the buffer, and figure
 325      * out how much data is left in our buffer, which we need to keep
 326      * around for the next request
 327      */
 328     leftoversz = (asState->reqofs + result.length) - (s - buf);
 329
 330     assert(leftoversz >= 0);
 331
 332     /*
 333      * Next, copy the left over data, from s to s + leftoversz to the
 334      * beginning of the buffer
 335      */
 336     memmove(buf, s, leftoversz);
 337
 338     /*
 339      * Next, update our offset and reqofs, and kick off a copy if required
 340      */
 341     asState->offset += result.length;
 342
 343     asState->reqofs = leftoversz;
 344
 345     debugs(53, 3, "asState->offset = " << asState->offset);
 346
 347     if (e->store_status == STORE_PENDING) {
 348         debugs(53, 3, "asHandleReply: store_status == STORE_PENDING: " << e->url()  );
 349         StoreIOBuffer tempBuffer (AS_REQBUF_SZ - asState->reqofs,
 350                                   asState->offset,
 351                                   asState->reqbuf + asState->reqofs);
 352         storeClientCopy(asState->sc,
 353                         e,
 354                         tempBuffer,
 355                         asHandleReply,
 356                         asState);
 357     } else {
 358         StoreIOBuffer tempBuffer;
 359         debugs(53, 3, "asHandleReply: store complete, but data received " << e->url()  );
 360         tempBuffer.offset = asState->offset;
 361         tempBuffer.length = AS_REQBUF_SZ - asState->reqofs;
 362         tempBuffer.data = asState->reqbuf + asState->reqofs;
 363         storeClientCopy(asState->sc,
 364                         e,
 365                         tempBuffer,
 366                         asHandleReply,
 367                         asState);
 368     }
 369 }
 370
 371 /**
 372  * add a network (addr, mask) to the radix tree, with matching AS number
 373  */
 374 static int
 375 asnAddNet(char *as_string, int as_number)
 376 {
 377     struct squid_radix_node *rn;
 378     CbDataList<int> **Tail = NULL;
 379     CbDataList<int> *q = NULL;
 380     as_info *asinfo = NULL;
 381
 382     Ip::Address mask;
 383     Ip::Address addr;
 384     char *t;
 385     int bitl;
 386
 387     t = strchr(as_string, '/');
 388
 389     if (t == NULL) {
 390         debugs(53, 3, "asnAddNet: failed, invalid response from whois server.");
 391         return 0;
 392     }
 393
 394     *t = '\0';
 395     addr = as_string;
 396     bitl = atoi(t + 1);
 397
 398     if (bitl < 0)
 399         bitl = 0;
 400
 401     // INET6 TODO : find a better way of identifying the base IPA family for mask than this.
 402     t = strchr(as_string, '.');
 403
 404     // generate Netbits Format Mask
 405     mask.setNoAddr();
 406     mask.applyMask(bitl, (t!=NULL?AF_INET:AF_INET6) );
 407
 408     debugs(53, 3, "asnAddNet: called for " << addr << "/" << mask );
 409
 410     rtentry_t *e = (rtentry_t *)xcalloc(1, sizeof(rtentry_t));
 411
 412     e->e_addr.addr = addr;
 413
 414     e->e_mask.addr = mask;
 415
 416     rn = squid_rn_lookup(&e->e_addr, &e->e_mask, AS_tree_head);
 417
 418     if (rn != NULL) {
 419         asinfo = ((rtentry_t *) rn)->e_info;
 420
 421         if (asinfo->as_number->find(as_number)) {
 422             debugs(53, 3, "asnAddNet: Ignoring repeated network '" << addr << "/" << bitl << "' for AS " << as_number);
 423         } else {
 424             debugs(53, 3, "asnAddNet: Warning: Found a network with multiple AS numbers!");
 425
 426             for (Tail = &asinfo->as_number; *Tail; Tail = &(*Tail)->next);
 427             q = new CbDataList<int> (as_number);
 428
 429             *(Tail) = q;
 430
 431             e->e_info = asinfo;
 432         }
 433     } else {
 434         q = new CbDataList<int> (as_number);
 435         asinfo = (as_info *)xmalloc(sizeof(as_info));
 436         asinfo->as_number = q;
 437         squid_rn_addroute(&e->e_addr, &e->e_mask, AS_tree_head, e->e_nodes);
 438         rn = squid_rn_match(&e->e_addr, AS_tree_head);
 439         assert(rn != NULL);
 440         e->e_info = asinfo;
 441     }
 442
 443     if (rn == 0) {      /* assert might expand to nothing */
 444         xfree(asinfo);
 445         delete q;
 446         xfree(e);
 447         debugs(53, 3, "asnAddNet: Could not add entry.");
 448         return 0;
 449     }
 450
 451     e->e_info = asinfo;
 452     return 1;
 453 }
 454
 455 static int
 456 destroyRadixNode(struct squid_radix_node *rn, void *w)
 457 {
 458
 459     struct squid_radix_node_head *rnh = (struct squid_radix_node_head *) w;
 460
 461     if (rn && !(rn->rn_flags & RNF_ROOT)) {
 462         rtentry_t *e = (rtentry_t *) rn;
 463         rn = squid_rn_delete(rn->rn_key, rn->rn_mask, rnh);
 464
 465         if (rn == 0)
 466             debugs(53, 3, "destroyRadixNode: internal screwup");
 467
 468         destroyRadixNodeInfo(e->e_info);
 469
 470         xfree(rn);
 471     }
 472
 473     return 1;
 474 }
 475
 476 static void
 477 destroyRadixNodeInfo(as_info * e_info)
 478 {
 479     CbDataList<int> *prev = NULL;
 480     CbDataList<int> *data = e_info->as_number;
 481
 482     while (data) {
 483         prev = data;
 484         data = data->next;
 485         delete prev;
 486     }
 487 }
 488
 489 static int
 490 printRadixNode(struct squid_radix_node *rn, void *_sentry)
 491 {
 492     StoreEntry *sentry = (StoreEntry *)_sentry;
 493     rtentry_t *e = (rtentry_t *) rn;
 494     CbDataList<int> *q;
 495     as_info *asinfo;
 496     char buf[MAX_IPSTRLEN];
 497     Ip::Address addr;
 498     Ip::Address mask;
 499
 500     assert(e);
 501     assert(e->e_info);
 502     addr = e->e_addr.addr;
 503     mask = e->e_mask.addr;
 504     storeAppendPrintf(sentry, "%s/%d\t",
 505                       addr.toStr(buf, MAX_IPSTRLEN),
 506                       mask.cidr() );
 507     asinfo = e->e_info;
 508     assert(asinfo->as_number);
 509
 510     for (q = asinfo->as_number; q; q = q->next)
 511         storeAppendPrintf(sentry, " %d", q->element);
 512
 513     storeAppendPrintf(sentry, "\n");
 514
 515     return 0;
 516 }
 517
 518 ACLASN::~ACLASN()
 519 {
 520     if (data)
 521         delete data;
 522 }
 523
 524 bool
 525
 526 ACLASN::match(Ip::Address toMatch)
 527 {
 528     return asnMatchIp(data, toMatch);
 529 }
 530
 531 SBufList
 532 ACLASN::dump() const
 533 {
 534     SBufList sl;
 535
 536     CbDataList<int> *ldata = data;
 537
 538     while (ldata != NULL) {
 539         SBuf s;
 540         s.Printf("%d", ldata->element);
 541         sl.push_back(s);
 542         ldata = ldata->next;
 543     }
 544
 545     return sl;
 546 }
 547
 548 bool
 549 ACLASN::empty () const
 550 {
 551     return data == NULL;
 552 }
 553
 554 void
 555 ACLASN::parse()
 556 {
 557     CbDataList<int> **curlist = &data;
 558     CbDataList<int> **Tail;
 559     CbDataList<int> *q = NULL;
 560     char *t = NULL;
 561
 562     for (Tail = curlist; *Tail; Tail = &((*Tail)->next));
 563     while ((t = ConfigParser::strtokFile())) {
 564         q = new CbDataList<int> (atoi(t));
 565         *(Tail) = q;
 566         Tail = &q->next;
 567     }
 568 }
 569
 570 ACLData<Ip::Address> *
 571 ACLASN::clone() const
 572 {
 573     if (data)
 574         fatal ("cloning of ACLASN not implemented");
 575
 576     return new ACLASN(*this);
 577 }
 578
 579 /* explicit template instantiation required for some systems */
 580
 581 template class ACLStrategised<Ip::Address>;
 582
 583 int
 584 ACLSourceASNStrategy::match (ACLData<Ip::Address> * &data, ACLFilledChecklist *checklist)
 585 {
 586     return data->match(checklist->src_addr);
 587 }
 588
 589 int
 590 ACLDestinationASNStrategy::match (ACLData<MatchType> * &data, ACLFilledChecklist *checklist)
 591 {
 592     const ipcache_addrs *ia = ipcache_gethostbyname(checklist->request->url.host(), IP_LOOKUP_IF_MISS);
 593
 594     if (ia) {
 595         for (int k = 0; k < (int) ia->count; ++k) {
 596             if (data->match(ia->in_addrs[k]))
 597                 return 1;
 598         }
 599
 600         return 0;
 601
 602     } else if (!checklist->request->flags.destinationIpLookedUp) {
 603         /* No entry in cache, lookup not attempted */
 604         debugs(28, 3, "can't yet compare '" << AclMatchedName << "' ACL for " << checklist->request->url.host());
 605         if (checklist->goAsync(DestinationIPLookup::Instance()))
 606             return -1;
 607         // else fall through to noaddr match, hiding the lookup failure (XXX)
 608     }
 609     Ip::Address noaddr;
 610     noaddr.setNoAddr();
 611     return data->match(noaddr);
 612 }
 613