| 1 | /* This file is part of the Linux Trace Toolkit viewer |
| 2 | * Copyright (C) 2009 Benjamin Poirier <benjamin.poirier@polymtl.ca> |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License Version 2 as |
| 6 | * published by the Free Software Foundation; |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, |
| 9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 11 | * GNU General Public License for more details. |
| 12 | * |
| 13 | * You should have received a copy of the GNU General Public License |
| 14 | * along with this program; if not, write to the Free Software |
| 15 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
| 16 | * MA 02111-1307, USA. |
| 17 | */ |
| 18 | |
| 19 | #ifdef HAVE_CONFIG_H |
| 20 | #include <config.h> |
| 21 | #endif |
| 22 | |
| 23 | #include <stdlib.h> |
| 24 | #include <string.h> |
| 25 | |
| 26 | #include "event_analysis.h" |
| 27 | #include "sync_chain.h" |
| 28 | |
| 29 | #include "event_matching_tcp.h" |
| 30 | |
| 31 | |
| 32 | #ifndef g_info |
| 33 | #define g_info(format...) g_log (G_LOG_DOMAIN, G_LOG_LEVEL_INFO, format) |
| 34 | #endif |
| 35 | |
| 36 | |
| 37 | // Functions common to all matching modules |
| 38 | static void initMatchingTCP(SyncState* const syncState); |
| 39 | static void destroyMatchingTCP(SyncState* const syncState); |
| 40 | |
| 41 | static void matchEventTCP(SyncState* const syncState, NetEvent* const event, |
| 42 | EventType eventType); |
| 43 | static GArray* finalizeMatchingTCP(SyncState* const syncState); |
| 44 | static void printMatchingStatsTCP(SyncState* const syncState); |
| 45 | |
| 46 | // Functions specific to this module |
| 47 | static void registerMatchingTCP() __attribute__((constructor (101))); |
| 48 | |
| 49 | static void matchEvents(SyncState* const syncState, NetEvent* const event, |
| 50 | GHashTable* const unMatchedList, GHashTable* const |
| 51 | unMatchedOppositeList, const size_t fieldOffset, const size_t |
| 52 | oppositeFieldOffset); |
| 53 | static void partialDestroyMatchingTCP(SyncState* const syncState); |
| 54 | |
| 55 | static bool isAck(const Packet* const packet); |
| 56 | static bool needsAck(const Packet* const packet); |
| 57 | static void buildReversedConnectionKey(ConnectionKey* const |
| 58 | reversedConnectionKey, const ConnectionKey* const connectionKey); |
| 59 | |
| 60 | |
| 61 | static MatchingModule matchingModuleTCP = { |
| 62 | .name= "TCP", |
| 63 | .initMatching= &initMatchingTCP, |
| 64 | .destroyMatching= &destroyMatchingTCP, |
| 65 | .matchEvent= &matchEventTCP, |
| 66 | .finalizeMatching= &finalizeMatchingTCP, |
| 67 | .printMatchingStats= &printMatchingStatsTCP, |
| 68 | }; |
| 69 | |
| 70 | |
| 71 | /* |
| 72 | * Matching module registering function |
| 73 | */ |
| 74 | static void registerMatchingTCP() |
| 75 | { |
| 76 | g_queue_push_tail(&matchingModules, &matchingModuleTCP); |
| 77 | } |
| 78 | |
| 79 | |
| 80 | /* |
| 81 | * Matching init function |
| 82 | * |
| 83 | * This function is called at the beginning of a synchronization run for a set |
| 84 | * of traces. |
| 85 | * |
| 86 | * Allocate the matching specific data structures |
| 87 | * |
| 88 | * Args: |
| 89 | * syncState container for synchronization data. |
| 90 | * This function allocates these matchingData members: |
| 91 | * unMatchedInE |
| 92 | * unMatchedOutE |
| 93 | * unAcked |
| 94 | * stats |
| 95 | */ |
| 96 | static void initMatchingTCP(SyncState* const syncState) |
| 97 | { |
| 98 | MatchingDataTCP* matchingData; |
| 99 | |
| 100 | matchingData= malloc(sizeof(MatchingDataTCP)); |
| 101 | syncState->matchingData= matchingData; |
| 102 | |
| 103 | matchingData->unMatchedInE= g_hash_table_new_full(&ghfPacketKeyHash, |
| 104 | &gefPacketKeyEqual, NULL, &gdnDestroyNetEvent); |
| 105 | matchingData->unMatchedOutE= g_hash_table_new_full(&ghfPacketKeyHash, |
| 106 | &gefPacketKeyEqual, NULL, &gdnDestroyNetEvent); |
| 107 | matchingData->unAcked= g_hash_table_new_full(&ghfConnectionKeyHash, |
| 108 | &gefConnectionKeyEqual, &gdnConnectionKeyDestroy, |
| 109 | &gdnPacketListDestroy); |
| 110 | |
| 111 | if (syncState->stats) |
| 112 | { |
| 113 | matchingData->stats= calloc(1, sizeof(MatchingStatsTCP)); |
| 114 | } |
| 115 | else |
| 116 | { |
| 117 | matchingData->stats= NULL; |
| 118 | } |
| 119 | } |
| 120 | |
| 121 | |
| 122 | /* |
| 123 | * Matching destroy function |
| 124 | * |
| 125 | * Free the matching specific data structures |
| 126 | * |
| 127 | * Args: |
| 128 | * syncState container for synchronization data. |
| 129 | * This function deallocates these matchingData members: |
| 130 | * stats |
| 131 | */ |
| 132 | static void destroyMatchingTCP(SyncState* const syncState) |
| 133 | { |
| 134 | MatchingDataTCP* matchingData; |
| 135 | |
| 136 | matchingData= (MatchingDataTCP*) syncState->matchingData; |
| 137 | |
| 138 | if (matchingData == NULL) |
| 139 | { |
| 140 | return; |
| 141 | } |
| 142 | |
| 143 | partialDestroyMatchingTCP(syncState); |
| 144 | |
| 145 | if (syncState->stats) |
| 146 | { |
| 147 | free(matchingData->stats); |
| 148 | } |
| 149 | |
| 150 | free(syncState->matchingData); |
| 151 | syncState->matchingData= NULL; |
| 152 | } |
| 153 | |
| 154 | |
| 155 | /* |
| 156 | * Free some of the matching specific data structures |
| 157 | * |
| 158 | * This function can be called right after the events have been processed to |
| 159 | * free some data structures that are not needed for finalization. |
| 160 | * |
| 161 | * Args: |
| 162 | * syncState container for synchronization data. |
| 163 | * This function deallocates these matchingData members: |
| 164 | * unMatchedInE |
| 165 | * unMatchedOut |
| 166 | * unAcked |
| 167 | */ |
| 168 | static void partialDestroyMatchingTCP(SyncState* const syncState) |
| 169 | { |
| 170 | MatchingDataTCP* matchingData; |
| 171 | |
| 172 | matchingData= (MatchingDataTCP*) syncState->matchingData; |
| 173 | |
| 174 | if (matchingData == NULL || matchingData->unMatchedInE == NULL) |
| 175 | { |
| 176 | return; |
| 177 | } |
| 178 | |
| 179 | g_debug("Cleaning up unMatchedInE list\n"); |
| 180 | g_hash_table_destroy(matchingData->unMatchedInE); |
| 181 | matchingData->unMatchedInE= NULL; |
| 182 | g_debug("Cleaning up unMatchedOutE list\n"); |
| 183 | g_hash_table_destroy(matchingData->unMatchedOutE); |
| 184 | g_debug("Cleaning up unAcked list\n"); |
| 185 | g_hash_table_destroy(matchingData->unAcked); |
| 186 | } |
| 187 | |
| 188 | |
| 189 | /* |
| 190 | * Try to match one event from a trace with the corresponding event from |
| 191 | * another trace. |
| 192 | * |
| 193 | * Args: |
| 194 | * syncState container for synchronization data. |
| 195 | * event new event to match |
| 196 | * eventType type of event to match |
| 197 | */ |
| 198 | static void matchEventTCP(SyncState* const syncState, NetEvent* const event, EventType eventType) |
| 199 | { |
| 200 | MatchingDataTCP* matchingData; |
| 201 | |
| 202 | matchingData= (MatchingDataTCP*) syncState->matchingData; |
| 203 | |
| 204 | if (eventType == IN) |
| 205 | { |
| 206 | matchEvents(syncState, event, matchingData->unMatchedInE, |
| 207 | matchingData->unMatchedOutE, offsetof(Packet, inE), |
| 208 | offsetof(Packet, outE)); |
| 209 | } |
| 210 | else |
| 211 | { |
| 212 | matchEvents(syncState, event, matchingData->unMatchedOutE, |
| 213 | matchingData->unMatchedInE, offsetof(Packet, outE), |
| 214 | offsetof(Packet, inE)); |
| 215 | } |
| 216 | } |
| 217 | |
| 218 | |
| 219 | /* |
| 220 | * Call the partial matching destroyer and Obtain the factors from downstream |
| 221 | * |
| 222 | * Args: |
| 223 | * syncState container for synchronization data. |
| 224 | * |
| 225 | * Returns: |
| 226 | * Factors[traceNb] synchronization factors for each trace |
| 227 | */ |
| 228 | static GArray* finalizeMatchingTCP(SyncState* const syncState) |
| 229 | { |
| 230 | partialDestroyMatchingTCP(syncState); |
| 231 | |
| 232 | return syncState->analysisModule->finalizeAnalysis(syncState); |
| 233 | } |
| 234 | |
| 235 | |
| 236 | /* |
| 237 | * Print statistics related to matching and downstream modules. Must be |
| 238 | * called after finalizeMatching. |
| 239 | * |
| 240 | * Args: |
| 241 | * syncState container for synchronization data. |
| 242 | */ |
| 243 | static void printMatchingStatsTCP(SyncState* const syncState) |
| 244 | { |
| 245 | MatchingDataTCP* matchingData; |
| 246 | |
| 247 | if (!syncState->stats) |
| 248 | { |
| 249 | return; |
| 250 | } |
| 251 | |
| 252 | matchingData= (MatchingDataTCP*) syncState->matchingData; |
| 253 | |
| 254 | printf("TCP matching stats:\n"); |
| 255 | printf("\ttotal input and output events matched together to form a packet: %d\n", |
| 256 | matchingData->stats->totPacket); |
| 257 | printf("\ttotal packets identified needing an acknowledge: %d\n", |
| 258 | matchingData->stats->totPacketNeedAck); |
| 259 | printf("\ttotal exchanges (four events matched together): %d\n", |
| 260 | matchingData->stats->totExchangeEffective); |
| 261 | printf("\ttotal synchronization exchanges: %d\n", |
| 262 | matchingData->stats->totExchangeSync); |
| 263 | |
| 264 | if (syncState->analysisModule->printAnalysisStats != NULL) |
| 265 | { |
| 266 | syncState->analysisModule->printAnalysisStats(syncState); |
| 267 | } |
| 268 | } |
| 269 | |
| 270 | |
| 271 | /* |
| 272 | * Implementation of a packet matching algorithm for TCP |
| 273 | * |
| 274 | * Args: |
| 275 | * netEvent: new event to match |
| 276 | * unMatchedList: list of unmatched events of the same type (send or |
| 277 | * receive) as netEvent |
| 278 | * unMatchedOppositeList: list of unmatched events of the opposite type of |
| 279 | * netEvent |
| 280 | * fieldOffset: offset of the NetEvent field in the Packet struct for the |
| 281 | * field of the type of netEvent |
| 282 | * oppositeFieldOffset: offset of the NetEvent field in the Packet struct |
| 283 | * for the field of the opposite type of netEvent |
| 284 | */ |
| 285 | static void matchEvents(SyncState* const syncState, NetEvent* const event, |
| 286 | GHashTable* const unMatchedList, GHashTable* const unMatchedOppositeList, |
| 287 | const size_t fieldOffset, const size_t oppositeFieldOffset) |
| 288 | { |
| 289 | NetEvent* companionEvent; |
| 290 | Packet* packet; |
| 291 | MatchingDataTCP* matchingData; |
| 292 | GQueue* conUnAcked; |
| 293 | |
| 294 | matchingData= (MatchingDataTCP*) syncState->matchingData; |
| 295 | |
| 296 | companionEvent= g_hash_table_lookup(unMatchedOppositeList, event->packetKey); |
| 297 | if (companionEvent != NULL) |
| 298 | { |
| 299 | g_debug("Found matching companion event, "); |
| 300 | |
| 301 | if (syncState->stats) |
| 302 | { |
| 303 | matchingData->stats->totPacket++; |
| 304 | } |
| 305 | |
| 306 | // If it's there, remove it and create a Packet |
| 307 | g_hash_table_steal(unMatchedOppositeList, event->packetKey); |
| 308 | packet= malloc(sizeof(Packet)); |
| 309 | *((NetEvent**) ((void*) packet + fieldOffset))= event; |
| 310 | *((NetEvent**) ((void*) packet + oppositeFieldOffset))= companionEvent; |
| 311 | // Both events can now share the same packetKey |
| 312 | free(packet->outE->packetKey); |
| 313 | packet->outE->packetKey= packet->inE->packetKey; |
| 314 | packet->acks= NULL; |
| 315 | |
| 316 | // Discard loopback traffic |
| 317 | if (packet->inE->traceNum == packet->outE->traceNum) |
| 318 | { |
| 319 | destroyPacket(packet); |
| 320 | return; |
| 321 | } |
| 322 | |
| 323 | if (syncState->analysisModule->analyzePacket) |
| 324 | { |
| 325 | syncState->analysisModule->analyzePacket(syncState, packet); |
| 326 | } |
| 327 | |
| 328 | // We can skip the rest of the algorithm if the analysis module is not |
| 329 | // interested in exchanges |
| 330 | if (!syncState->analysisModule->analyzeExchange) |
| 331 | { |
| 332 | destroyPacket(packet); |
| 333 | return; |
| 334 | } |
| 335 | |
| 336 | // If this packet acknowleges some data ... |
| 337 | if (isAck(packet)) |
| 338 | { |
| 339 | ConnectionKey oppositeConnectionKey; |
| 340 | |
| 341 | buildReversedConnectionKey(&oppositeConnectionKey, |
| 342 | &event->packetKey->connectionKey); |
| 343 | conUnAcked= g_hash_table_lookup(matchingData->unAcked, |
| 344 | &oppositeConnectionKey); |
| 345 | if (conUnAcked != NULL) |
| 346 | { |
| 347 | Packet* ackedPacket; |
| 348 | GList* result; |
| 349 | |
| 350 | result= g_queue_find_custom(conUnAcked, packet, &gcfPacketAckCompare); |
| 351 | |
| 352 | while (result != NULL) |
| 353 | { |
| 354 | // Remove the acknowledged packet from the unAcked list |
| 355 | // and keep it for later offset calculations |
| 356 | g_debug("Found matching unAcked packet, "); |
| 357 | |
| 358 | ackedPacket= (Packet*) result->data; |
| 359 | g_queue_delete_link(conUnAcked, result); |
| 360 | |
| 361 | if (syncState->stats) |
| 362 | { |
| 363 | matchingData->stats->totExchangeEffective++; |
| 364 | } |
| 365 | |
| 366 | if (packet->acks == NULL) |
| 367 | { |
| 368 | packet->acks= g_queue_new(); |
| 369 | } |
| 370 | |
| 371 | g_queue_push_tail(packet->acks, ackedPacket); |
| 372 | |
| 373 | result= g_queue_find_custom(conUnAcked, packet, |
| 374 | &gcfPacketAckCompare); |
| 375 | } |
| 376 | |
| 377 | // It might be possible to do an offset calculation |
| 378 | if (packet->acks != NULL) |
| 379 | { |
| 380 | ackedPacket= g_queue_peek_tail(packet->acks); |
| 381 | if (ackedPacket->outE->traceNum != packet->inE->traceNum |
| 382 | || ackedPacket->inE->traceNum != |
| 383 | packet->outE->traceNum || packet->inE->traceNum == |
| 384 | packet->outE->traceNum) |
| 385 | { |
| 386 | printPacket(ackedPacket); |
| 387 | printPacket(packet); |
| 388 | g_error("Disorganized exchange encountered during " |
| 389 | "synchronization"); |
| 390 | } |
| 391 | else |
| 392 | { |
| 393 | if (syncState->stats) |
| 394 | { |
| 395 | matchingData->stats->totExchangeSync++; |
| 396 | } |
| 397 | |
| 398 | syncState->analysisModule->analyzeExchange(syncState, |
| 399 | packet); |
| 400 | } |
| 401 | } |
| 402 | } |
| 403 | } |
| 404 | |
| 405 | if (needsAck(packet)) |
| 406 | { |
| 407 | if (syncState->stats) |
| 408 | { |
| 409 | matchingData->stats->totPacketNeedAck++; |
| 410 | } |
| 411 | |
| 412 | // If this packet will generate an ack, add it to the unAcked list |
| 413 | g_debug("Adding to unAcked, "); |
| 414 | conUnAcked= g_hash_table_lookup(matchingData->unAcked, |
| 415 | &event->packetKey->connectionKey); |
| 416 | if (conUnAcked == NULL) |
| 417 | { |
| 418 | ConnectionKey* connectionKey; |
| 419 | |
| 420 | connectionKey= malloc(sizeof(ConnectionKey)); |
| 421 | memcpy(connectionKey, &event->packetKey->connectionKey, |
| 422 | sizeof(ConnectionKey)); |
| 423 | g_hash_table_insert(matchingData->unAcked, connectionKey, |
| 424 | conUnAcked= g_queue_new()); |
| 425 | } |
| 426 | g_queue_push_tail(conUnAcked, packet); |
| 427 | } |
| 428 | else |
| 429 | { |
| 430 | destroyPacket(packet); |
| 431 | } |
| 432 | } |
| 433 | else |
| 434 | { |
| 435 | // If there's no corresponding event, add the event to the unmatched |
| 436 | // list for this type of event |
| 437 | g_debug("Adding to unmatched event list, "); |
| 438 | g_hash_table_replace(unMatchedList, event->packetKey, event); |
| 439 | } |
| 440 | } |
| 441 | |
| 442 | |
| 443 | /* |
| 444 | * Check if a packet is an acknowledge |
| 445 | * |
| 446 | * Returns: |
| 447 | * true if it is, |
| 448 | * false otherwise |
| 449 | */ |
| 450 | static bool isAck(const Packet* const packet) |
| 451 | { |
| 452 | if (packet->inE->packetKey->ack == 1) |
| 453 | { |
| 454 | return true; |
| 455 | } |
| 456 | else |
| 457 | { |
| 458 | return false; |
| 459 | } |
| 460 | } |
| 461 | |
| 462 | |
| 463 | /* |
| 464 | * Check if a packet will increment the sequence number, thus needing an |
| 465 | * acknowledge |
| 466 | * |
| 467 | * Returns: |
| 468 | * true if the packet will need an acknowledge |
| 469 | * false otherwise |
| 470 | */ |
| 471 | static bool needsAck(const Packet* const packet) |
| 472 | { |
| 473 | if (packet->inE->packetKey->syn || packet->inE->packetKey->fin || |
| 474 | packet->inE->packetKey->tot_len - packet->inE->packetKey->ihl * 4 - |
| 475 | packet->inE->packetKey->doff * 4 > 0) |
| 476 | { |
| 477 | return true; |
| 478 | } |
| 479 | else |
| 480 | { |
| 481 | return false; |
| 482 | } |
| 483 | } |
| 484 | |
| 485 | |
| 486 | /* |
| 487 | * Populate a connection key structure for the opposite direction of a |
| 488 | * connection |
| 489 | * |
| 490 | * Args: |
| 491 | * reversedConnectionKey the result, must be pre-allocated |
| 492 | * connectionKey the connection key to reverse |
| 493 | */ |
| 494 | static void buildReversedConnectionKey(ConnectionKey* const |
| 495 | reversedConnectionKey, const ConnectionKey* const connectionKey) |
| 496 | { |
| 497 | reversedConnectionKey->saddr= connectionKey->daddr; |
| 498 | reversedConnectionKey->daddr= connectionKey->saddr; |
| 499 | reversedConnectionKey->source= connectionKey->dest; |
| 500 | reversedConnectionKey->dest= connectionKey->source; |
| 501 | } |